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  1. Polycystic kidney disease in the medaka (Oryzias latipes pc mutant caused by a mutation in the Gli-Similar3 (glis3 gene.

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    Hisashi Hashimoto

    Full Text Available Polycystic kidney disease (PKD is a common hereditary disease in humans. Recent studies have shown an increasing number of ciliary genes that are involved in the pathogenesis of PKD. In this study, the Gli-similar3 (glis3 gene was identified as the causal gene of the medaka pc mutant, a model of PKD. In the pc mutant, a transposon was found to be inserted into the fourth intron of the pc/glis3 gene, causing aberrant splicing of the pc/glis3 mRNA and thus a putatively truncated protein with a defective zinc finger domain. pc/glis3 mRNA is expressed in the epithelial cells of the renal tubules and ducts of the pronephros and mesonephros, and also in the pancreas. Antisense oligonucleotide-mediated knockdown of pc/glis3 resulted in cyst formation in the pronephric tubules of medaka fry. Although three other glis family members, glis1a, glis1b and glis2, were found in the medaka genome, none were expressed in the embryonic or larval kidney. In the pc mutant, the urine flow rate in the pronephros was significantly reduced, which was considered to be a direct cause of renal cyst formation. The cilia on the surface of the renal tubular epithelium were significantly shorter in the pc mutant than in wild-type, suggesting that shortened cilia resulted in a decrease in driving force and, in turn, a reduction in urine flow rate. Most importantly, EGFP-tagged pc/glis3 protein localized in primary cilia as well as in the nucleus when expressed in mouse renal epithelial cells, indicating a strong connection between pc/glis3 and ciliary function. Unlike human patients with GLIS3 mutations, the medaka pc mutant shows none of the symptoms of a pancreatic phenotype, such as impaired insulin expression and/or diabetes, suggesting that the pc mutant may be suitable for use as a kidney-specific model for human GLIS3 patients.

  2. Nuclear protein import is reduced in cells expressing nuclear envelopathy-causing lamin A mutants

    International Nuclear Information System (INIS)

    Busch, Albert; Kiel, Tilman; Heupel, Wolfgang-M.; Wehnert, Manfred; Huebner, Stefan

    2009-01-01

    Lamins, which form the nuclear lamina, not only constitute an important determinant of nuclear architecture, but additionally play essential roles in many nuclear functions. Mutations in A-type lamins cause a wide range of human genetic disorders (laminopathies). The importance of lamin A (LaA) in the spatial arrangement of nuclear pore complexes (NPCs) prompted us to study the role of LaA mutants in nuclear protein transport. Two mutants, causing prenatal skin disease restrictive dermopathy (RD) and the premature aging disease Hutchinson Gilford progeria syndrome, were used for expression in HeLa cells to investigate their impact on the subcellular localization of NPC-associated proteins and nuclear protein import. Furthermore, dynamics of the LaA mutants within the nuclear lamina were studied. We observed affected localization of NPC-associated proteins, diminished lamina dynamics for both LaA mutants and reduced nuclear import of representative cargo molecules. Intriguingly, both LaA mutants displayed similar effects on nuclear morphology and functions, despite their differences in disease severity. Reduced nuclear protein import was also seen in RD fibroblasts and impaired lamina dynamics for the nucleoporin Nup153. Our data thus represent the first study of a direct link between LaA mutant expression and reduced nuclear protein import.

  3. ALS-causing profilin-1-mutant forms a non-native helical structure in membrane environments.

    Science.gov (United States)

    Lim, Liangzhong; Kang, Jian; Song, Jianxing

    2017-11-01

    Despite having physiological functions completely different from superoxide dismutase 1 (SOD1), profilin 1 (PFN1) also carries mutations causing amyotrophic lateral sclerosis (ALS) with a striking similarity to that triggered by SOD1 mutants. Very recently, the C71G-PFN1 has been demonstrated to cause ALS by a gain of toxicity and the acceleration of motor neuron degeneration preceded the accumulation of its aggregates. Here by atomic-resolution NMR determination of conformations and dynamics of WT-PFN1 and C71G-PFN1 in aqueous buffers and in membrane mimetics DMPC/DHPC bicelle and DPC micelle, we deciphered that: 1) the thermodynamic destabilization by C71G transforms PFN1 into coexistence with the unfolded state, which is lacking of any stable tertiary/secondary structures as well as restricted ps-ns backbone motions, thus fundamentally indistinguishable from ALS-causing SOD1 mutants. 2) Most strikingly, while WT-PFN1 only weakly interacts with DMPC/DHPC bicelle without altering the native structure, C71G-PFN1 acquires abnormal capacity in strongly interacting with DMPC/DHPC bicelle and DPC micelle, energetically driven by transforming the highly disordered unfolded state into a non-native helical structure, similar to what has been previously observed on ALS-causing SOD1 mutants. Our results imply that one potential mechanism for C71G-PFN1 to initiate ALS might be the abnormal interaction with membranes as recently established for SOD1 mutants. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Xenopus pax6 mutants affect eye development and other organ systems, and have phenotypic similarities to human aniridia patients.

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    Nakayama, Takuya; Fisher, Marilyn; Nakajima, Keisuke; Odeleye, Akinleye O; Zimmerman, Keith B; Fish, Margaret B; Yaoita, Yoshio; Chojnowski, Jena L; Lauderdale, James D; Netland, Peter A; Grainger, Robert M

    2015-12-15

    Mutations in the Pax6 gene cause ocular defects in both vertebrate and invertebrate animal species, and the disease aniridia in humans. Despite extensive experimentation on this gene in multiple species, including humans, we still do not understand the earliest effects on development mediated by this gene. This prompted us to develop pax6 mutant lines in Xenopus tropicalis taking advantage of the utility of the Xenopus system for examining early development and in addition to establish a model for studying the human disease aniridia in an accessible lower vertebrate. We have generated mutants in pax6 by using Transcription Activator-Like Effector Nuclease (TALEN) constructs for gene editing in X. tropicalis. Embryos with putative null mutations show severe eye abnormalities and changes in brain development, as assessed by changes in morphology and gene expression. One gene that we found is downregulated very early in development in these pax6 mutants is myc, a gene involved in pluripotency and progenitor cell maintenance and likely a mediator of some key pax6 functions in the embryo. Changes in gene expression in the developing brain and pancreas reflect other important functions of pax6 during development. In mutations with partial loss of pax6 function eye development is initially relatively normal but froglets show an underdeveloped iris, similar to the classic phenotype (aniridia) seen in human patients with PAX6 mutations. Other eye abnormalities observed in these froglets, including cataracts and corneal defects, are also common in human aniridia. The frog model thus allows us to examine the earliest deficits in eye formation as a result of pax6 lesions, and provides a useful model for understanding the developmental basis for the aniridia phenotype seen in humans. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Reaction of some soybean mutant lines to natural rust fungus caused by (phakopsora pachyrhizi syd)

    International Nuclear Information System (INIS)

    Ratma, R.

    1988-01-01

    Reaction of some soybean mutant lines to natural rust fungus caused by (phakopsora pachyhizi syd). Eleven soybean mutant lines of orba variety derived from gamma fungus disease in the wet season 1985/86 at the experimental station of Citayam, Bogor. Based on IWGSR rating system, soybean mutant lines No 18/PsJ was moderately resistant to rust fungus disease. The other mutant lines, 14/PsJ, 15/PsJ, 20/PsJ, 102/PsJ, 106/PsJ, 111/PsJ, 118/PsJ, 119/PsJ and 220/PsJ were susceptible. (author). 4 figs.; 8 refs

  6. Similar phenotypes caused by mutations in OTOG and OTOGL

    Science.gov (United States)

    Oonk, Anne M.M.; Leijendeckers, Joop M.; Huygen, Patrick L.M.; Schraders, Margit; del Campo, Miguel; del Castillo, Ignacio; Tekin, Mustafa; Feenstra, Ilse; Beynon, Andy J.; Kunst, Henricus P.M.; Snik, Ad F.M.; Kremer, Hannie; Admiraal, Ronald J.C.; Pennings, Ronald J.E.

    2013-01-01

    Objectives recently, OTOG and OTOGL were identified as human deafness genes. Currently, only four families are known to have autosomal recessive hearing loss based on mutations in these genes. Since the two genes code for proteins (otogelin and otogelin-like) that are strikingly similar in structure and localization in the inner ear, this study is focused on characterizing and comparing the hearing loss caused by mutations in these genes. Design To evaluate this type of hearing, an extensive set of audiometric and vestibular examinations was performed in the 13 patients from four families. Results all families show a flat to downsloping configuration of the audiogram with mild to moderate sensorineural hearing loss. Speech recognition scores remain good (>90%). Hearing loss is not significantly different in the four families and the psychophysical test results also do not differ between the families. Vestibular examinations show evidence for vestibular hyporeflexia. Conclusion since otogelin and otogelin-like are localized in the tectorial membrane, one could expect a cochlear conductive hearing loss, as was previously shown in DFNA13 (COL11A2) and DFNA8/12 (TECTA) patients. Results of psychophysical examinations, however, do not support this. Furthermore, the authors can conclude that there are no phenotypic differences between hearing loss based on mutations in OTOG or OTOGL. This phenotype description will facilitate counseling of hearing loss caused by defects in either of these two genes. PMID:24378291

  7. Expression of CALR mutants causes mpl-dependent thrombocytosis in zebrafish.

    Science.gov (United States)

    Lim, K-H; Chang, Y-C; Chiang, Y-H; Lin, H-C; Chang, C-Y; Lin, C-S; Huang, L; Wang, W-T; Gon-Shen Chen, C; Chou, W-C; Kuo, Y-Y

    2016-10-07

    CALR mutations are identified in about 30% of JAK2/MPL-unmutated myeloproliferative neoplasms (MPNs) including essential thrombocythemia (ET) and primary myelofibrosis. Although the molecular pathogenesis of CALR mutations leading to MPNs has been studied using in vitro cell lines models, how mutant CALR may affect developmental hematopoiesis remains unknown. Here we took advantage of the zebrafish model to examine the effects of mutant CALR on early hematopoiesis and model human CALR-mutated MPNs. We identified three zebrafish genes orthologous to human CALR, referred to as calr, calr3a and calr3b. The expression of CALR-del52 and CALR-ins5 mutants caused an increase in the hematopoietic stem/progenitor cells followed by thrombocytosis without affecting normal angiogenesis. The expression of CALR mutants also perturbed early developmental hematopoiesis in zebrafish. Importantly, morpholino knockdown of mpl but not epor or csf3r could significantly attenuate the effects of mutant CALR. Furthermore, the expression of mutant CALR caused jak-stat signaling activation in zebrafish that could be blocked by JAK inhibitors (ruxolitinib and fedratinib). These findings showed that mutant CALR activates jak-stat signaling through an mpl-dependent mechanism to mediate pathogenic thrombopoiesis in zebrafish, and illustrated that the signaling machinery related to mutant CALR tumorigenesis are conserved between human and zebrafish.

  8. POSTFUNDOPLICATION DYSPHAGIA CAUSES SIMILAR WATER INGESTION DYNAMICS AS ACHALASIA.

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    Dantas, Roberto Oliveira; Santos, Carla Manfredi; Cassiani, Rachel Aguiar; Alves, Leda Maria Tavares; Nascimento, Weslania Viviane

    2016-01-01

    - After surgical treatment of gastroesophageal reflux disease dysphagia is a symptom in the majority of patients, with decrease in intensity over time. However, some patients may have persistent dysphagia. - The objective of this investigation was to evaluate the dynamics of water ingestion in patients with postfundoplication dysphagia compared with patients with dysphagia caused by achalasia, idiopathic or consequent to Chagas' disease, and controls. - Thirty-three patients with postfundoplication dysphagia, assessed more than one year after surgery, together with 50 patients with Chagas' disease, 27 patients with idiopathic achalasia and 88 controls were all evaluated by the water swallow test. They drunk, in triplicate, 50 mL of water without breaks while being precisely timed and the number of swallows counted. Also measured was: (a) inter-swallows interval - the time to complete the task, divided by the number of swallows during the task; (b) swallowing flow - volume drunk divided by the time taken; (c) volume of each swallow - volume drunk divided by the number of swallows. - Patients with postfundoplication dysphagia, Chagas' disease and idiopathic achalasia took longer to ingest all the volume, had an increased number of swallows, an increase in interval between swallows, a decrease in swallowing flow and a decrease in water volume of each swallow compared with the controls. There was no difference between the three groups of patients. There was no correlation between postfundoplication time and the results. - It was concluded that patients with postfundoplication dysphagia have similar water ingestion dynamics as patients with achalasia.

  9. POSTFUNDOPLICATION DYSPHAGIA CAUSES SIMILAR WATER INGESTION DYNAMICS AS ACHALASIA

    Directory of Open Access Journals (Sweden)

    Roberto Oliveira DANTAS

    Full Text Available ABSTRACT Background - After surgical treatment of gastroesophageal reflux disease dysphagia is a symptom in the majority of patients, with decrease in intensity over time. However, some patients may have persistent dysphagia. Objective - The objective of this investigation was to evaluate the dynamics of water ingestion in patients with postfundoplication dysphagia compared with patients with dysphagia caused by achalasia, idiopathic or consequent to Chagas' disease, and controls. Methods - Thirty-three patients with postfundoplication dysphagia, assessed more than one year after surgery, together with 50 patients with Chagas' disease, 27 patients with idiopathic achalasia and 88 controls were all evaluated by the water swallow test. They drunk, in triplicate, 50 mL of water without breaks while being precisely timed and the number of swallows counted. Also measured was: (a inter-swallows interval - the time to complete the task, divided by the number of swallows during the task; (b swallowing flow - volume drunk divided by the time taken; (c volume of each swallow - volume drunk divided by the number of swallows. Results - Patients with postfundoplication dysphagia, Chagas' disease and idiopathic achalasia took longer to ingest all the volume, had an increased number of swallows, an increase in interval between swallows, a decrease in swallowing flow and a decrease in water volume of each swallow compared with the controls. There was no difference between the three groups of patients. There was no correlation between postfundoplication time and the results. Conclusion - It was concluded that patients with postfundoplication dysphagia have similar water ingestion dynamics as patients with achalasia.

  10. Rescue of glaucoma-causing mutant myocilin thermal stability by chemical chaperones

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    Burns, J. Nicole; Orwig, Susan D.; Harris, Julia L.; Watkins, J. Derrick; Vollrath, Douglas; Lieberman, Raquel L.

    2010-01-01

    Mutations in myocilin cause an inherited form of open angle glaucoma, a prevalent neurodegenerative disorder associated with increased intraocular pressure. Myocilin forms part of the trabecular meshwork extracellular matrix presumed to regulate intraocular pressure. Missense mutations, clustered in the olfactomedin (OLF) domain of myocilin, render the protein prone to aggregation in the endoplasmic reticulum of trabecular meshwork cells, causing cell dysfunction and death. Cellular studies have demonstrated temperature-sensitive secretion of myocilin mutants, but difficulties in expression and purification have precluded biophysical characterization of wild-type (wt) myocilin and disease-causing mutants in vitro. We have overcome these limitations by purifying wt and select glaucoma-causing mutant (D380A, I477N, I477S, K423E) forms of the OLF domain (228–504) fused to maltose binding protein (MBP) from E. coli. Monomeric fusion proteins can be isolated in solution. To determine the relative stability of wt and mutant OLF domains, we developed a fluorescence thermal stability assay without removal of MBP, and provide the first direct evidence that mutated OLF is folded but less thermally stable than wt. We tested the ability of seven chemical chaperones to stabilize mutant myocilin. Only sarcosine and trimethylamine N-oxide were capable of shifting the melting temperature of all mutants tested to near that of wt OLF. Our work lays the foundation for the identification of tailored small molecules capable of stabilizing mutant myocilin and promoting secretion to the extracellular matrix, to better control intraocular pressure and ultimately delay the onset of myocilin glaucoma. PMID:20334347

  11. Meiotic UV-sensitive mutant that causes deletion of duplications in neurospora

    International Nuclear Information System (INIS)

    Newmeyer, D.; Galeazzi, D.R.

    1978-01-01

    The meiotic-3 (mei-3) mutant of Neurospora crassa has several effects: (1) when homozygous, it almost completely blocks meiosis and ascospore formation, (2) it is sensitive to uv, (3) its growth is inhibited by histidine, and (4) it increases the instability of nontandem duplications. This was shown for duplications produced by five different rearrangements and was demonstrated by two different criteria. The effects on meiosis and duplication instability are expressed strongly at 25 0 ; the effects on sensitivity to uv and to histidine are expressed strongly at 38.5 0 but only slightly at 25 0 . Nevertheless, all four effects were shown to be due to a single gene. Mei-3 is not allelic with previously reported uv-sensitive mutants. Two other results were obtained that are not necessarily due to mei-3: (1) a cross involving mei-3 produced a new unlinked meiotic mutant, mei-4, which is not sensitive to uv or histidine, and (2) a burst of several new mutants occurred in a different mei-3 stock, including a partial revertant to mei-3. Mei-3 has previously been shown to cause frequent complete loss of a terminal duplicate segment, beginning exactly at the original rearrangement breakpoint. Possible mechanisms are discussed by which a uv-sensitive mutant could cause such precise deletions

  12. Noonan syndrome-causing SHP2 mutants impair ERK-dependent chondrocyte differentiation during endochondral bone growth.

    Science.gov (United States)

    Tajan, Mylène; Pernin-Grandjean, Julie; Beton, Nicolas; Gennero, Isabelle; Capilla, Florence; Neel, Benjamin G; Araki, Toshiyuki; Valet, Philippe; Tauber, Maithé; Salles, Jean-Pierre; Yart, Armelle; Edouard, Thomas

    2018-04-12

    Growth retardation is a constant feature of Noonan syndrome (NS) but its physiopathology remains poorly understood. We previously reported that hyperactive NS-causing SHP2 mutants impair the systemic production of insulin-like growth factor 1 (IGF1) through hyperactivation of the RAS/extracellular signal-regulated kinases (ERK) signalling pathway. Besides endocrine defects, a direct effect of these mutants on growth plate has not been explored, although recent studies have revealed an important physiological role for SHP2 in endochondral bone growth. We demonstrated that growth plate length was reduced in NS mice, mostly due to a shortening of the hypertrophic zone and to a lesser extent of the proliferating zone. These histological features were correlated with decreased expression of early chondrocyte differentiation markers, and with reduced alkaline phosphatase staining and activity, in NS murine primary chondrocytes. Although IGF1 treatment improved growth of NS mice, it did not fully reverse growth plate abnormalities, notably the decreased hypertrophic zone. In contrast, we documented a role of RAS/ERK hyperactivation at the growth plate level since 1) NS-causing SHP2 mutants enhance RAS/ERK activation in chondrocytes in vivo (NS mice) and in vitro (ATDC5 cells) and 2) inhibition of RAS/ERK hyperactivation by U0126 treatment alleviated growth plate abnormalities and enhanced chondrocyte differentiation. Similar effects were obtained by chronic treatment of NS mice with statins.In conclusion, we demonstrated that hyperactive NS-causing SHP2 mutants impair chondrocyte differentiation during endochondral bone growth through a local hyperactivation of the RAS/ERK signalling pathway, and that statin treatment may be a possible therapeutic approach in NS.

  13. Recombinant deamidated mutants of Erwinia chrysanthemi L-asparaginase have similar or increased activity compared to wild-type enzyme.

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    Gervais, David; Foote, Nicholas

    2014-10-01

    The enzyme Erwinia chrysanthemi L-asparaginase (ErA) is an important biopharmaceutical product used in the treatment of acute lymphoblastic leukaemia. Like all proteins, certain asparagine (Asn) residues of ErA are susceptible to deamidation to aspartic acid (Asp), which may be a concern with respect to enzyme activity and potentially to pharmaceutical efficacy. Recombinant ErA mutants containing Asn to Asp changes were expressed, purified and characterised. Two mutants with single deamidation sites (N41D and N281D) were found to have approximately the same specific activity (1,062 and 924 U/mg, respectively) as the wild-type (908 U/mg). However, a double mutant (N41D N281D) had an increased specific activity (1261 U/mg). The N41D mutation conferred a slight increase in the catalytic constant (k cat 657 s(-1)) when compared to the WT (k cat 565 s(-1)), which was further increased in the double mutant, with a k cat of 798 s(-1). Structural analyses showed that the slight changes caused by point mutation of Asn41 to Asp may have reduced the number of hydrogen bonds in this α-helical part of the protein structure, resulting in subtle changes in enzyme turnover, both structurally and catalytically. The increased α-helical content observed with the N41D mutation by circular dichroism spectroscopy correlates with the difference in k cat, but not K m. The N281D mutation resulted in a lower glutaminase activity compared with WT and the N41D mutant, however the N281D mutation also imparted less stability to the enzyme at elevated temperatures. Taken as a whole, these data suggest that ErA deamidation at the Asn41 and Asn281 sites does not affect enzyme activity and should not be a concern during processing, storage or clinical use. The production of recombinant deamidated variants has proven an effective and powerful means of studying the effect of these changes and may be a useful strategy for other biopharmaceutical products.

  14. Sex reversal in zebrafish fancl mutants is caused by Tp53-mediated germ cell apoptosis.

    Directory of Open Access Journals (Sweden)

    Adriana Rodríguez-Marí

    2010-07-01

    Full Text Available The molecular genetic mechanisms of sex determination are not known for most vertebrates, including zebrafish. We identified a mutation in the zebrafish fancl gene that causes homozygous mutants to develop as fertile males due to female-to-male sex reversal. Fancl is a member of the Fanconi Anemia/BRCA DNA repair pathway. Experiments showed that zebrafish fancl was expressed in developing germ cells in bipotential gonads at the critical time of sexual fate determination. Caspase-3 immunoassays revealed increased germ cell apoptosis in fancl mutants that compromised oocyte survival. In the absence of oocytes surviving through meiosis, somatic cells of mutant gonads did not maintain expression of the ovary gene cyp19a1a and did not down-regulate expression of the early testis gene amh; consequently, gonads masculinized and became testes. Remarkably, results showed that the introduction of a tp53 (p53 mutation into fancl mutants rescued the sex-reversal phenotype by reducing germ cell apoptosis and, thus, allowed fancl mutants to become fertile females. Our results show that Fancl function is not essential for spermatogonia and oogonia to become sperm or mature oocytes, but instead suggest that Fancl function is involved in the survival of developing oocytes through meiosis. This work reveals that Tp53-mediated germ cell apoptosis induces sex reversal after the mutation of a DNA-repair pathway gene by compromising the survival of oocytes and suggests the existence of an oocyte-derived signal that biases gonad fate towards the female developmental pathway and thereby controls zebrafish sex determination.

  15. Structural and functional analysis of the ASM p.Ala359Asp mutant that causes acid sphingomyelinase deficiency.

    Science.gov (United States)

    Acuña, Mariana; Castro-Fernández, Víctor; Latorre, Mauricio; Castro, Juan; Schuchman, Edward H; Guixé, Victoria; González, Mauricio; Zanlungo, Silvana

    2016-10-21

    Niemann-Pick disease (NPD) type A and B are recessive hereditary disorders caused by deficiency in acid sphingomyelinase (ASM). The p.Ala359Asp mutation has been described in several patients but its functional and structural effects in the protein are unknown. In order to characterize this mutation, we modeled the three-dimensional ASM structure using the recent available crystal of the mammalian ASM as a template. We found that the p.Ala359Asp mutation is localized in the hydrophobic core and far from the sphingomyelin binding site. However, energy function calculations using statistical potentials indicate that the mutation causes a decrease in ASM stability. Therefore, we investigated the functional effect of the p.Ala359Asp mutation in ASM expression, secretion, localization and activity in human fibroblasts. We found a 3.8% residual ASM activity compared to the wild-type enzyme, without changes in the other parameters evaluated. These results support the hypothesis that the p.Ala359Asp mutation causes structural alterations in the hydrophobic environment where ASM is located, decreasing its enzymatic activity. A similar effect was observed in other previously described NPDB mutations located outside the active site of the enzyme. This work shows the first full size ASM mutant model describe at date, providing a complete analysis of the structural and functional effects of the p.Ala359Asp mutation over the stability and activity of the enzyme. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Relationship between intracellular Na+ concentration and reduced Na+ affinity in Na+,K+-ATPase mutants causing neurological disease

    DEFF Research Database (Denmark)

    Toustrup-Jensen, Mads Schak; Einholm, Anja P.; Schack, Vivien

    The neurological disorders familial hemiplegic migraine type 2 (FHM2), alternating hemiplegia of childhood (AHC), and rapid-onset dystonia parkinsonism (RDP) are caused by mutations of Na+,K+-ATPase α2 and α3 isoforms, expressed in glial and neuronal cells, respectively. Although these disorders......, addressing the question to what extent they cause a change of the intracellular Na+ and K+ concentrations ([Na+]i and [K+]i) in COS cells. C-terminal extension mutants generally showed dramatically reduced Na+ affinity without disturbance of K+ binding, as did other RDP mutants. No phosphorylation from ATP...

  17. Mutant alpha-synuclein causes age-dependent neuropathology in monkey brain.

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    Yang, Weili; Wang, Guohao; Wang, Chuan-En; Guo, Xiangyu; Yin, Peng; Gao, Jinquan; Tu, Zhuchi; Wang, Zhengbo; Wu, Jing; Hu, Xintian; Li, Shihua; Li, Xiao-Jiang

    2015-05-27

    Parkinson's disease (PD) is an age-dependent neurodegenerative disease that often occurs in those over age 60. Although rodents and small animals have been used widely to model PD and investigate its pathology, their short life span makes it difficult to assess the aging-related pathology that is likely to occur in PD patient brains. Here, we used brain tissues from rhesus monkeys at 2-3, 7-8, and >15 years of age to examine the expression of Parkin, PINK1, and α-synuclein, which are known to cause PD via loss- or gain-of-function mechanisms. We found that α-synuclein is increased in the older monkey brains, whereas Parkin and PINK1 are decreased or remain unchanged. Because of the gain of toxicity of α-synuclein, we performed stereotaxic injection of lentiviral vectors expressing mutant α-synuclein (A53T) into the substantia nigra of monkeys and found that aging also increases the accumulation of A53T in neurites and its associated neuropathology. A53T also causes more extensive reactive astrocytes and axonal degeneration in monkey brain than in mouse brain. Using monkey brain tissues, we found that A53T interacts with neurofascin, an adhesion molecule involved in axon subcellular targeting and neurite outgrowth. Aged monkey brain tissues show an increased interaction of neurofascin with A53T. Overexpression of A53T causes neuritic toxicity in cultured neuronal cells, which can be attenuated by transfected neurofascin. These findings from nonhuman primate brains reveal age-dependent pathological and molecular changes that could contribute to the age-dependent neuropathology in PD. Copyright © 2015 the authors 0270-6474/15/358345-14$15.00/0.

  18. Functional Loss of Bmsei Causes Thermosensitive Epilepsy in Contractile Mutant Silkworm, Bombyx mori

    Science.gov (United States)

    Nie, Hongyi; Cheng, Tingcai; Huang, Xiaofeng; Zhou, Mengting; Zhang, Yinxia; Dai, Fangyin; Mita, Kazuei; Xia, Qingyou; Liu, Chun

    2015-07-01

    The thermoprotective mechanisms of insects remain largely unknown. We reported the Bombyx mori contractile (cot) behavioral mutant with thermo-sensitive seizures phenotype. At elevated temperatures, the cot mutant exhibit seizures associated with strong contractions, rolling, vomiting, and a temporary lack of movement. We narrowed a region containing cot to ~268 kb by positional cloning and identified the mutant gene as Bmsei which encoded a potassium channel protein. Bmsei was present in both the cell membrane and cytoplasm in wild-type ganglia but faint in cot. Furthermore, Bmsei was markedly decreased upon high temperature treatment in cot mutant. With the RNAi method and injecting potassium channel blockers, the wild type silkworm was induced the cot phenotype. These results demonstrated that Bmsei was responsible for the cot mutant phenotype and played an important role in thermoprotection in silkworm. Meanwhile, comparative proteomic approach was used to investigate the proteomic differences. The results showed that the protein of Hsp-1 and Tn1 were significantly decreased and increased on protein level in cot mutant after thermo-stimulus, respectively. Our data provide insights into the mechanism of thermoprotection in insect. As cot phenotype closely resembles human epilepsy, cot might be a potential model for the mechanism of epilepsy in future.

  19. Structure-Function Correlation Analysis of Connexin50 Missense Mutations Causing Congenital Cataract: Electrostatic Potential Alteration Could Determine Intracellular Trafficking Fate of Mutants

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    Devroop Sarkar

    2014-01-01

    Full Text Available Connexin50 (Cx50 mutations are reported to cause congenital cataract probably through the disruption of intercellular transport in the lens. Cx50 mutants that undergo mistrafficking have generally been associated with failure to form functional gap junction channels; however, sometimes even properly trafficked mutants were found to undergo similar consequences. We hereby wanted to elucidate any structural bases of the varied functional consequences of Cx50 missense mutations through in silico approach. Computational studies have been done based on a Cx50 homology model to assess conservation, solvent accessibility, and 3-dimensional localization of mutated residues as well as mutation-induced changes in surface electrostatic potential, H-bonding, and steric clash. This was supplemented with meta-analysis of published literature on the functional properties of connexin missense mutations. Analyses revealed that the mutation-induced critical alterations of surface electrostatic potential in Cx50 mutants could determine their fate in intracellular trafficking. A similar pattern was observed in case of mutations involving corresponding conserved residues in other connexins also. Based on these results the trafficking fates of 10 uncharacterized Cx50 mutations have been predicted. Further experimental analyses are needed to validate the observed correlation.

  20. Chloroplast Dysfunction Causes Multiple Defects in Cell Cycle Progression in the Arabidopsis crumpled leaf Mutant

    KAUST Repository

    Hudik, Elodie

    2014-07-18

    The majority of research on cell cycle regulation is focused on the nuclear events that govern the replication and segregation of the genome between the two daughter cells. However, eukaryotic cells contain several compartmentalized organelles with specialized functions, and coordination among these organelles is required for proper cell cycle progression, as evidenced by the isolation of several mutants in which both organelle function and overall plant development were affected. To investigate how chloroplast dysfunction affects the cell cycle, we analyzed the crumpled leaf (crl) mutant of Arabidopsis (Arabidopsis thaliana), which is deficient for a chloroplastic protein and displays particularly severe developmental defects. In the crl mutant, we reveal that cell cycle regulation is altered drastically and that meristematic cells prematurely enter differentiation, leading to reduced plant stature and early endoreduplication in the leaves. This response is due to the repression of several key cell cycle regulators as well as constitutive activation of stress-response genes, among them the cell cycle inhibitor SIAMESE-RELATED5. One unique feature of the crl mutant is that it produces aplastidic cells in several organs, including the root tip. By investigating the consequence of the absence of plastids on cell cycle progression, we showed that nuclear DNA replication occurs in aplastidic cells in the root tip, which opens future research prospects regarding the dialogue between plastids and the nucleus during cell cycle regulation in higher plants.

  1. DNA Misfolding Found to Cause Cancer in IDH-mutant Gliomas

    Science.gov (United States)

    Researchers studying IDH-mutant brain tumors have identified a previously unknown genetic mechanism that may contribute to cancer. A change in how DNA is arranged, or packaged, in the cell nucleus may inappropriately activate a gene associated with brain cancer.

  2. FATP4 missense and nonsense mutations cause similar features in Ichthyosis Prematurity Syndrome

    Directory of Open Access Journals (Sweden)

    Dahl Niklas

    2011-03-01

    Full Text Available Abstract Background Ichthyosis Prematurity Syndrome (IPS is an autosomal recessive disorder characterized by premature birth, non-scaly ichthyosis and atopic manifestations. The disease was recently shown to be caused by mutations in the gene encoding the fatty acid transport protein 4 (FATP4 and a specific reduction in the incorporation of very long chain fatty acids (VLCFA into cellular lipids. Findings We screened probands from five families segregating IPS for mutations in the FATP4 gene. Four probands were compound heterozygous for four different mutations of which three are novel. Four patients were heterozygous and one patient homozygous for the previously reported non-sense mutation p.C168X (c.504c > a. All patients had clinical characteristics of IPS and a similar clinical course. Conclusions Missense mutations and non-sense mutations in FATP4 are associated with similar clinical features suggesting that missense mutations have a severe impact on FATP4 function. The results broaden the mutational spectrum in FATP4 associated with IPS for molecular diagnosis of and further functional analysis of FATP4.

  3. Primary coenzyme Q deficiency in Pdss2 mutant mice causes isolated renal disease.

    Directory of Open Access Journals (Sweden)

    Min Peng

    2008-04-01

    Full Text Available Coenzyme Q (CoQ is an essential electron carrier in the respiratory chain whose deficiency has been implicated in a wide variety of human mitochondrial disease manifestations. Its multi-step biosynthesis involves production of polyisoprenoid diphosphate in a reaction that requires the enzymes be encoded by PDSS1 and PDSS2. Homozygous mutations in either of these genes, in humans, lead to severe neuromuscular disease, with nephrotic syndrome seen in PDSS2 deficiency. We now show that a presumed autoimmune kidney disease in mice with the missense Pdss2(kd/kd genotype can be attributed to a mitochondrial CoQ biosynthetic defect. Levels of CoQ9 and CoQ10 in kidney homogenates from B6.Pdss2(kd/kd mutants were significantly lower than those in B6 control mice. Disease manifestations originate specifically in glomerular podocytes, as renal disease is seen in Podocin/cre,Pdss2(loxP/loxP knockout mice but not in conditional knockouts targeted to renal tubular epithelium, monocytes, or hepatocytes. Liver-conditional B6.Alb/cre,Pdss2(loxP/loxP knockout mice have no overt disease despite demonstration that their livers have undetectable CoQ9 levels, impaired respiratory capacity, and significantly altered intermediary metabolism as evidenced by transcriptional profiling and amino acid quantitation. These data suggest that disease manifestations of CoQ deficiency relate to tissue-specific respiratory capacity thresholds, with glomerular podocytes displaying the greatest sensitivity to Pdss2 impairment.

  4. Paternal or Maternal Uniparental Disomy of Chromosome 16 Resulting in Homozygosity of a Mutant Allele Causes Fanconi Anemia.

    Science.gov (United States)

    Donovan, Frank X; Kimble, Danielle C; Kim, Yonghwan; Lach, Francis P; Harper, Ursula; Kamat, Aparna; Jones, MaryPat; Sanborn, Erica M; Tryon, Rebecca; Wagner, John E; MacMillan, Margaret L; Ostrander, Elaine A; Auerbach, Arleen D; Smogorzewska, Agata; Chandrasekharappa, Settara C

    2016-05-01

    Fanconi anemia (FA) is a rare inherited disorder caused by pathogenic variants in one of 19 FANC genes. FA patients display congenital abnormalities, and develop bone marrow failure, and cancer susceptibility. We identified homozygous mutations in four FA patients and, in each case, only one parent carried the obligate mutant allele. FANCA and FANCP/SLX4 genes, both located on chromosome 16, were the affected recessive FA genes in three and one family respectively. Genotyping with short tandem repeat markers and SNP arrays revealed uniparental disomy (UPD) of the entire mutation-carrying chromosome 16 in all four patients. One FANCA patient had paternal UPD, whereas FA in the other three patients resulted from maternal UPD. These are the first reported cases of UPD as a cause of FA. UPD indicates a reduced risk of having another child with FA in the family and has implications in prenatal diagnosis. © 2016 WILEY PERIODICALS, INC.

  5. Posterior semicircular canal dehiscence: a morphologic cause of vertigo similar to superior semicircular canal dehiscence

    International Nuclear Information System (INIS)

    Krombach, G.A.; Schmitz-Rode, T.; Haage, P.; Guenther, R.W.; DiMartino, E.; Prescher, A.; Kinzel, S.

    2003-01-01

    Heading Abstract.The aim of this study was to assess imaging findings of posterior semicircular dehiscence on computed tomography and to evaluate incidence of posterior and superior semicircular canal dehiscence in patients presenting with vertigo, sensorineuronal hearing loss or in a control group without symptoms related to the inner ear. Computed tomography was performed in 507 patients presenting either with vertigo (n=128; 23 of these patients suffered also from sensorineuronal hearing loss), other symptoms related to the inner ear, such as hearing loss or tinnitus (n=183) or symptoms unrelated to the labyrinth (n=196). All images were reviewed for presence of dehiscence of the bone, overlying the semicircular canals. Twenty-nine patients had superior semicircular canal dehiscence. Of these patients, 83% presented with vertigo, 10% with hearing loss or tinnitus and the remaining 7% with symptoms unrelated to the inner ear. In 23 patients dehiscence of the posterior semicircular canal was encountered. Of these patients, 86% presented with vertigo, 9% with hearing loss or tinnitus and 5% with symptoms unrelated to the inner ear. Defects of the bony overly are found at the posterior semicircular canal, in addition to the recently introduced superior canal dehiscence syndrome. Significant prevalence of vertigo in these patients suggests that posterior semicircular canal dehiscence can cause vertigo, similar to superior semicircular canal dehiscence. (orig.)

  6. Posterior semicircular canal dehiscence: a morphologic cause of vertigo similar to superior semicircular canal dehiscence

    Energy Technology Data Exchange (ETDEWEB)

    Krombach, G A; Schmitz-Rode, T; Haage, P; Guenther, R W [Department of Diagnostic Radiology, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany); DiMartino, E [Department of Otorhinolaryngology, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany); Prescher, A [Department of Anatomy, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany); Kinzel, S [Department of Experimental Veterinarian Medicine, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany)

    2003-06-01

    Heading Abstract.The aim of this study was to assess imaging findings of posterior semicircular dehiscence on computed tomography and to evaluate incidence of posterior and superior semicircular canal dehiscence in patients presenting with vertigo, sensorineuronal hearing loss or in a control group without symptoms related to the inner ear. Computed tomography was performed in 507 patients presenting either with vertigo (n=128; 23 of these patients suffered also from sensorineuronal hearing loss), other symptoms related to the inner ear, such as hearing loss or tinnitus (n=183) or symptoms unrelated to the labyrinth (n=196). All images were reviewed for presence of dehiscence of the bone, overlying the semicircular canals. Twenty-nine patients had superior semicircular canal dehiscence. Of these patients, 83% presented with vertigo, 10% with hearing loss or tinnitus and the remaining 7% with symptoms unrelated to the inner ear. In 23 patients dehiscence of the posterior semicircular canal was encountered. Of these patients, 86% presented with vertigo, 9% with hearing loss or tinnitus and 5% with symptoms unrelated to the inner ear. Defects of the bony overly are found at the posterior semicircular canal, in addition to the recently introduced superior canal dehiscence syndrome. Significant prevalence of vertigo in these patients suggests that posterior semicircular canal dehiscence can cause vertigo, similar to superior semicircular canal dehiscence. (orig.)

  7. A cataract-causing connexin 50 mutant is mislocalized to the ER due to loss of the fourth transmembrane domain and cytoplasmic domain.

    Science.gov (United States)

    Somaraju Chalasani, Madhavi Latha; Muppirala, Madhavi; G Ponnam, Surya Prakash; Kannabiran, Chitra; Swarup, Ghanshyam

    2013-01-01

    Mutations in the eye lens gap junction protein connexin 50 cause cataract. Earlier we identified a frameshift mutant of connexin 50 (c.670insA; p.Thr203AsnfsX47) in a family with autosomal recessive cataract. The mutant protein is smaller and contains 46 aberrant amino acids at the C-terminus after amino acid 202. Here, we have analysed this frameshift mutant and observed that it localized to the endoplasmic reticulum (ER) but not in the plasma membrane. Moreover, overexpression of the mutant resulted in disintegration of the ER-Golgi intermediate compartment (ERGIC), reduction in the level of ERGIC-53 protein and breakdown of the Golgi in many cells. Overexpression of the frameshift mutant partially inhibited the transport of wild type connexin 50 to the plasma membrane. A deletion mutant lacking the aberrant sequence showed predominant localization in the ER and inhibited anterograde protein transport suggesting, therefore, that the aberrant sequence is not responsible for improper localization of the frameshift mutant. Further deletion analysis showed that the fourth transmembrane domain and a membrane proximal region (231-294 amino acids) of the cytoplasmic domain are needed for transport from the ER and localization to the plasma membrane. Our results show that a frameshift mutant of connexin 50 mislocalizes to the ER and causes disintegration of the ERGIC and Golgi. We have also identified a sequence of connexin 50 crucial for transport from the ER and localization to the plasma membrane.

  8. Sodium 4-phenylbutyrate ameliorates the effects of cataract-causing mutant gammaD-crystallin in cultured cells.

    Science.gov (United States)

    Gong, Bo; Zhang, Li-Yun; Lam, Dennis Shun-Chiu; Pang, Chi-Pui; Yam, Gary Hin-Fai

    2010-06-04

    gammaD-Crystallin (CRYGD) is a major structural lens crystallin and its mutations result in congenital cataract formation. In this study, we attempted to correct the altered protein features of G165fsX8 CRYGD protein with small chemical molecules. Recombinant FLAG-tagged mutants (R15C, R15S, P24T, R61C, and G165fsX8) of CRYGD were expressed in COS-7 cells and treated with small chemical molecules with reported protein chaperoning properties (sodium 4-phenylbutyrate [4-PBA], trimethylamine N-oxide [TMAO], and glycerol and DMSO [DMSO]). Protein solubility in 0.5% Triton X-100 and subcellular distribution was examined by western blotting and immunofluorescence, respectively. Apoptosis was assayed as the percentage of fragmented nuclei in transfected cells. Expression of heat-shock proteins (Hsp70 and Hsp90) was examined by reverse transcription-polymerase chain reaction analysis. Unlike WT and most mutants (R15C, R15S, P24T, and R61C) of CRYGD, G165fsX8 CRYGD was significantly insoluble in 0.5% Triton X-100. This insolubility was alleviated by dose-dependent 4-PBA treatment. The treatment relieved the mislocalization of G165fsX8 CRYGD from the nuclear envelope. Also, 4-PBA treatment reduced cell apoptosis and caused an upregulation of Hsp70. 4-PBA treatment reduced the defective phenotype of mutant G165fsX8 CRYGD and rescued the affected cells from apoptosis. This could be a potential treatment for lens structural protein and prevent lens opacity in cataract formation.

  9. Reversed polarized delivery of an aquaporin-2 mutant causes dominant nephrogenic diabetes insipidus.

    NARCIS (Netherlands)

    Kamsteeg, E.J.; Bichet, D.G.; Konings, I.B.M.; Nivet, H.; Lonergan, M.; Arthus, M.F.; Os, C.H. van; Deen, P.M.T.

    2003-01-01

    Vasopressin regulates body water conservation by redistributing aquaporin-2 (AQP2) water channels from intracellular vesicles to the apical surface of renal collecting ducts, resulting in water reabsorption from urine. Mutations in AQP2 cause autosomal nephrogenic diabetes insipidus (NDI), a disease

  10. Aniridia-associated cytogenetic rearrangements suggest that a position effect may cause the mutant phenotype

    NARCIS (Netherlands)

    Fantes, J.; Redeker, B.; Breen, M.; Boyle, S.; Brown, J.; Fletcher, J.; Jones, S.; Bickmore, W.; Fukushima, Y.; Mannens, M.

    1995-01-01

    Current evidence suggests that aniridia (absence of iris) is caused by loss of function of one copy of the PAX6 gene, which maps to 11p13. We present the further characterisation of two aniridia pedigrees in which the disease segregates with chromosomal rearrangements which involve 11p13 but do not

  11. Long-term oil contamination causes similar changes in microbial communities of two distinct soils.

    Science.gov (United States)

    Liao, Jingqiu; Wang, Jie; Jiang, Dalin; Wang, Michael Cai; Huang, Yi

    2015-12-01

    Since total petroleum hydrocarbons (TPH) are toxic and persistent in environments, studying the impact of oil contamination on microbial communities in different soils is vital to oil production engineering, effective soil management and pollution control. This study analyzed the impact of oil contamination on the structure, activity and function in carbon metabolism of microbial communities of Chernozem soil from Daqing oil field and Cinnamon soil from Huabei oil field through both culture-dependent techniques and a culture-independent technique-pyrosequencing. Results revealed that pristine microbial communities in these two soils presented disparate patterns, where Cinnamon soil showed higher abundance of alkane, (polycyclic aromatic hydrocarbons) PAHs and TPH degraders, number of cultivable microbes, bacterial richness, bacterial biodiversity, and stronger microbial activity and function in carbon metabolism than Chernozem soil. It suggested that complicated properties of microbes and soils resulted in the difference in soil microbial patterns. However, the changes of microbial communities caused by oil contamination were similar in respect of two dominant phenomena. Firstly, the microbial community structures were greatly changed, with higher abundance, higher bacterial biodiversity, occurrence of Candidate_division_BRC1 and TAO6, disappearance of BD1-5 and Candidate_division_OD1, dominance of Streptomyces, higher percentage of hydrocarbon-degrading groups, and lower percentage of nitrogen-transforming groups. Secondly, microbial activity and function in carbon metabolism were significantly enhanced. Based on the characteristics of microbial communities in the two soils, appropriate strategy for in situ bioremediation was provided for each oil field. This research underscored the usefulness of combination of culture-dependent techniques and next-generation sequencing techniques both to unravel the microbial patterns and understand the ecological impact of

  12. Excessive Myosin Activity in Mbs Mutants Causes Photoreceptor Movement Out of the Drosophila Eye Disc Epithelium

    OpenAIRE

    Lee, Arnold; Treisman, Jessica E.

    2004-01-01

    Neuronal cells must extend a motile growth cone while maintaining the cell body in its original position. In migrating cells, myosin contraction provides the driving force that pulls the rear of the cell toward the leading edge. We have characterized the function of myosin light chain phosphatase, which down-regulates myosin activity, in Drosophila photoreceptor neurons. Mutations in the gene encoding the myosin binding subunit of this enzyme cause photoreceptors to drop out of the eye disc e...

  13. Characterization of two second-site mutations preventing wild type protein aggregation caused by a dominant negative PMA1 mutant.

    Directory of Open Access Journals (Sweden)

    Pilar Eraso

    Full Text Available The correct biogenesis and localization of Pma1 at the plasma membrane is essential for yeast growth. A subset of PMA1 mutations behave as dominant negative because they produce aberrantly folded proteins that form protein aggregates, which in turn provoke the aggregation of the wild type protein. One approach to understand this dominant negative effect is to identify second-site mutations able to suppress the dominant lethal phenotype caused by those mutant alleles. We isolated and characterized two intragenic second-site suppressors of the PMA1-D378T dominant negative mutation. We present here the analysis of these new mutations that are located along the amino-terminal half of the protein and include a missense mutation, L151F, and an in-frame 12bp deletion that eliminates four residues from Cys409 to Ala412. The results show that the suppressor mutations disrupt the interaction between the mutant and wild type enzymes, and this enables the wild type Pma1 to reach the plasma membrane.

  14. Mechanical Defects of Muscle Fibers with Myosin Light Chain Mutants that Cause Cardiomyopathy

    OpenAIRE

    Roopnarine, Osha

    2003-01-01

    Familial hypertrophic cardiomyopathy is a disease caused by single mutations in several sarcomeric proteins, including the human myosin ventricular regulatory light chain (vRLC). The effects of four of these mutations (A13T, F18L, E22K, and P95A) in vRLC on force generation were determined as a function of Ca2+ concentration. The endogenous RLC was removed from skinned rabbit psoas muscle fibers, and replaced with either rat wildtype vRLC or recombinant rat vRLC (G13T, F18L, E22K, and P95A). ...

  15. The late flowering phenotype of fwa mutants is caused by gain-of-function epigenetic alleles of a homeodomain gene

    NARCIS (Netherlands)

    Soppe, W.J.J.; Jacobsen, S.E.; Alonso-Blanco, C.; Jackson, J.P.; Kakutani, T.; Koornneef, M.; Peeters, A.J.M.

    2000-01-01

    The transition to flowering in Arabidopsis thaliana is delayed in fwa mutant plants. FWA was identified by loss-of-function mutations in normally flowering revertants of the fwa mutant, and it encodes a homeodomain-containing transcription factor. The DNA sequence of wild-type and fwa mutant alleles

  16. What can long-lived mutants tell us about mechanisms causing aging and lifespan variation in natural environments?

    NARCIS (Netherlands)

    Briga, Michael; Verhulst, Simon

    2015-01-01

    Long-lived mutants of model organisms have brought remarkable progress in our understanding of aging mechanisms. However, long-lived mutants are usually maintained in optimal standardized laboratory environments (SLEs), and it is not obvious to what extent insights from long-lived mutants in SLEs

  17. A thermolabile aldolase A mutant causes fever-induced recurrent rhabdomyolysis without hemolytic anemia.

    Directory of Open Access Journals (Sweden)

    Asmaa Mamoune

    2014-11-01

    Full Text Available Aldolase A deficiency has been reported as a rare cause of hemolytic anemia occasionally associated with myopathy. We identified a deleterious homozygous mutation in the ALDOA gene in 3 siblings with episodic rhabdomyolysis without hemolytic anemia. Myoglobinuria was always triggered by febrile illnesses. We show that the underlying mechanism involves an exacerbation of aldolase A deficiency at high temperatures that affected myoblasts but not erythrocytes. The aldolase A deficiency was rescued by arginine supplementation in vitro but not by glycerol, betaine or benzylhydantoin, three other known chaperones, suggesting that arginine-mediated rescue operated by a mechanism other than protein chaperoning. Lipid droplets accumulated in patient myoblasts relative to control and this was increased by cytokines, and reduced by dexamethasone. Our results expand the clinical spectrum of aldolase A deficiency to isolated temperature-dependent rhabdomyolysis, and suggest that thermolability may be tissue specific. We also propose a treatment for this severe disease.

  18. Chernobyl and Fukushima. Similarity and dissimilarity in their cause and outcome

    International Nuclear Information System (INIS)

    Shibata, Yoshisada

    2011-01-01

    We compared the two worst nuclear accidents rated INES 7, which occurred at the Chernobyl and the Fukushima Daiichi Nuclear Power Plants. Although the human errors underlie both accidents, the respective causes differed. The accident at Chernobyl was caused by the experiment which resulted in increase in criticality and activity leading to a powerful steam explosion and fire that released a significant fraction of core material into the environment, while that at Fukushima Daiichi was due to the damage to the backup power and containment systems caused by the destructive tsunami waves triggered by the 2011 earthquake off the Pacific coast of Tohoku. The physical health effects of the Chernobyl accident demonstrated so far in general population around Chernobyl are thyroid diseases including cancer in those exposed to the accident in their childhood. The long-term program monitoring for at least 30 years the health conditions of all Fukushima residents will be introduced. (author)

  19. Escherichia coli Isolates Causing Asymptomatic Bacteriuria in Catheterized and Noncatheterized Individuals Possess Similar Virulence Properties

    DEFF Research Database (Denmark)

    Watts, Rebecca E; Hancock, Viktoria; Ong, Cheryl-lynn Y

    2010-01-01

    Urinary tract infections (UTIs) are among the most common infectious diseases of humans, with Escherichia coli being responsible for >80% of all cases. Asymptomatic bacteriuria (ABU) occurs when bacteria colonize the urinary tract without causing clinical symptoms and can affect both catheterized...... patients (catheter-associated ABU [CA-ABU]) and noncatheterized patients. Here, we compared the virulence properties of a collection of ABU and CA-ABU nosocomial E. coli isolates in terms of antibiotic resistance, phylogenetic grouping, specific UTI-associated virulence genes, hemagglutination...

  20. Structural similarity causes different category-effects depending on task characteristics

    DEFF Research Database (Denmark)

    Gerlach, Christian

    2001-01-01

    difference was found on easy object decision tasks. In experiment 2 an advantage for natural objects was found during object decisions performed under degraded viewing conditions (lateralized stimulus presentation). It is argued that these findings can be accounted for by assuming that natural objects...... it is in difficult object decision tasks). However, when viewing conditions are degraded and performance tends to depend on global shape information (carried by low spatial frequency components), natural objects may fare better than artefacts because the global shape of natural objects reveals more of their identity......It has been suggested that category-specific impairments for natural objects may reflect that natural objects are more globally visually similar than artefacts and therefore more difficult to recognize following brain damage [Aphasiology 13 (1992) 169]. This account has been challenged...

  1. Deregulation of the actin cytoskeleton and macropinocytosis in response to phorbol ester by the mutant protein kinase C gamma that causes spinocerebellar ataxia type 14

    Directory of Open Access Journals (Sweden)

    Kazuhiro eYamamoto

    2014-04-01

    Full Text Available Several missense mutations in the protein kinase Cγ (γPKC gene have been found to cause spinocerebellar ataxia type 14 (SCA14, an autosomal dominant neurodegenerative disease. γPKC is a neuron-specific member of the classical PKCs and is activated and translocated to subcellular regions as a result of various stimuli, including diacylglycerol synthesis, increased intracellular Ca2+ and phorbol esters. We investigated whether SCA14 mutations affect the γPKC-related functions by stimulating HeLa cells with TPA (12-O-tetradecanoylpholbol 13-acetate, a type of phorbol ester. Wild-type (WT γPKC-GFP was translocated to the plasma membrane within 10 min of TPA stimulation, followed by its perinuclear translocation and cell shrinkage, in a PKC kinase activity- and microtubule-dependent manner. On the other hand, although SCA14 mutant γPKC-GFP exhibited a similar translocation to the plasma membrane, the subsequent perinuclear translocation and cell shrinkage were significantly impaired in response to TPA. Translocated WT γPKC colocalized with F-actin and formed large vesicular structures in the perinuclear region. The uptake of FITC-dextran, a marker of macropinocytosis, was promoted by TPA stimulation in cells expressing WT γPKC, and FITC-dextran was surrounded by γPKC-positive vesicles. Moreover, TPA induced the phosphorylation of MARCKS, which is a membrane-substrate of PKC, resulting in the translocation of phosphorylated MARCKS to the perinuclear region, suggesting that TPA induces macropinocytosis via γPKC activation. However, TPA failed to activate macropinocytosis and trigger the translocation of phosphorylated MARCKS in cells expressing the SCA14 mutant γPKC. These findings suggest that γPKC is involved in the regulation of the actin cytoskeleton and macropinocytosis in HeLa cells, while SCA14 mutant γPKC fails to regulate these processes due to its reduced kinase activity at the plasma membrane. This property might be involved in

  2. Climate change and physical disturbance cause similar community shifts in biological soil crusts

    Science.gov (United States)

    Ferrenberg, Scott; Reed, Sasha C.; Belnap, Jayne

    2015-01-01

    Biological soil crusts (biocrusts)—communities of mosses, lichens, cyanobacteria, and heterotrophs living at the soil surface—are fundamental components of drylands worldwide, and destruction of biocrusts dramatically alters biogeochemical processes, hydrology, surface energy balance, and vegetation cover. While there has been long-standing concern over impacts of 5 physical disturbances on biocrusts (e.g., trampling by livestock, damage from vehicles), there is also increasing concern over the potential for climate change to alter biocrust community structure. Using long-term data from the Colorado Plateau, USA, we examined the effects of 10 years of experimental warming and altered precipitation (in full-factorial design) on biocrust communities, and compared the effects of altered climate with those of long-term physical 10 disturbance (>10 years of replicated human trampling). Surprisingly, altered climate and physical disturbance treatments had similar effects on biocrust community structure. Warming, altered precipitation frequency [an increase of small (1.2 mm) summer rainfall events], and physical disturbance from trampling all promoted early successional community states marked by dramatic declines in moss cover and increased cyanobacteria cover, with more variable effects 15 on lichens. While the pace of community change varied significantly among treatments, our results suggest that multiple aspects of climate change will affect biocrusts to the same degree as physical disturbance. This is particularly disconcerting in the context of warming, as temperatures for drylands are projected to increase beyond those imposed by the climate treatments used in our study.

  3. Early Events in Retinal Degeneration Caused by Rhodopsin Mutation or Pigment Epithelium Malfunction: Differences and Similarities

    Science.gov (United States)

    Di Pierdomenico, Johnny; García-Ayuso, Diego; Pinilla, Isabel; Cuenca, Nicolás; Vidal-Sanz, Manuel; Agudo-Barriuso, Marta; Villegas-Pérez, María P.

    2017-01-01

    To study the course of photoreceptor cell death and macro and microglial reactivity in two rat models of retinal degeneration with different etiologies. Retinas from P23H-1 (rhodopsin mutation) and Royal College of Surgeon (RCS, pigment epithelium malfunction) rats and age-matched control animals (Sprague-Dawley and Pievald Viro Glaxo, respectively) were cross-sectioned at different postnatal ages (from P10 to P60) and rhodopsin, L/M- and S-opsin, ionized calcium-binding adapter molecule 1 (Iba1), glial fibrillary acid protein (GFAP), and proliferating cell nuclear antigen (PCNA) proteins were immunodetected. Photoreceptor nuclei rows and microglial cells in the different retinal layers were quantified. Photoreceptor degeneration starts earlier and progresses quicker in P23H-1 than in RCS rats. In both models, microglial cell activation occurs simultaneously with the initiation of photoreceptor death while GFAP over-expression starts later. As degeneration progresses, the numbers of microglial cells increase in the retina, but decreasing in the inner retina and increasing in the outer retina, more markedly in RCS rats. Interestingly, and in contrast with healthy animals, microglial cells reach the outer nuclei and outer segment layers. The higher number of microglial cells in dystrophic retinas cannot be fully accounted by intraretinal migration and PCNA immunodetection revealed microglial proliferation in both models but more importantly in RCS rats. The etiology of retinal degeneration determines the initiation and pattern of photoreceptor cell death and simultaneously there is microglial activation and migration, while the macroglial response is delayed. The actions of microglial cells in the degeneration cannot be explained only in the basis of photoreceptor death because they participate more actively in the RCS model. Thus, the retinal degeneration caused by pigment epithelium malfunction is more inflammatory and would probably respond better to interventions

  4. Calcium-Induced Activation of a Mutant G-Protein-Coupled Receptor Causes In Vitro Transformation of NIH/3T3 Cells

    Directory of Open Access Journals (Sweden)

    Ana O. Hoff

    1999-12-01

    Full Text Available The calcium-sensing receptor (CaR is a G-proteincoupled receptor that is widely expressed, has tissuespecific functions, regulates cell growth. Activating mutations of this receptor cause autosomal dominant hypocalcemia, a syndrome characterized by hypocalcemia and hypercalciuria. The identification of a family with an activating mutation of the CaR (Thr151 Met in which hypocalcemia cosegregates with several unusual neoplasms led us to examine the transforming effects of this mutant receptor. Transfection of NIH/3T3 cells with the mutant but not the normal receptor supported colony formation in soft agar at subphysiologic calcium concentrations. The mutant CaR causes a calcium-dependent activation of the extracellular signal-regulated protein kinase (ERK 1/2 and Jun-N-terminal kinase/stress-activated (JNK/ SAPK pathways, but not P38 MAP kinase. These findings contribute to a growing body of information suggesting that this receptor plays a role in the regulation of cellular proliferation, that aberrant activation of the mutant receptor in this family may play a role in the unusual neoplastic manifestations.

  5. Detection of quantitative trait loci causing abnormal spermatogenesis and reduced testis weight in the small testis (Smt) mutant mouse.

    Science.gov (United States)

    Bolor, Hasbaira; Wakasugi, Noboru; Zhao, Wei Dong; Ishikawa, Akira

    2006-04-01

    The small testis (Smt) mutant mouse is characterized by a small testis of one third to one half the size of a normal testis, and its spermatogenesis is mostly arrested at early stages of meiosis, although a small number of spermatocytes at the late prophase of meiosis and a few spermatids can sometimes be seen. We performed quantitative trait locus (QTL) analysis of these spermatogenic traits and testis weight using 221 F2 males obtained from a cross between Smt and MOM (Mus musculus molossinus) mice. At the genome-wide 5% level, we detected two QTLs affecting meiosis on chromosomes 4 and 13, and two QTLs for paired testis weight as a percentage of body weight on chromosomes 4 and X. In addition, we found several QTLs for degenerated germ cells and multinuclear giant cells on chromosomes 4, 7 and 13. Interestingly, for cell degeneration, the QTL on chromosome 13 interacted epistatically with the QTL on chromosome 4. These results reveal polygenic participation in the abnormal spermatogenesis and small testis size in the Smt mutant.

  6. The einkorn wheat (Triticum monococcum) mutant, maintained vegetative phase, is caused by a deletion in the VRN1 gene

    International Nuclear Information System (INIS)

    Shitsukawa, N.; Ikari, C.; Shimada, S.; Kitagawa, S.; Sakamoto, K.; Saito, H.; Ryuto, H.; Fukunishi, N.; Abe, T.; Takumi, S.; Nasuda, S.; Murai, K.

    2007-01-01

    The einkorn wheat (Triticum monococcum) mutant, maintained vegetative phase (mvp), was induced by nitrogen ion-beam treatment and was identified by its inability to transit from the vegetative to reproductive phase. In our previous study, we showed that WAP1 (wheat APETALA1) is a key gene in the regulatory pathway that controls phase transition from vegetative to reproductive growth in common wheat. WAP1 is an ortholog of the VRN1 gene that is responsible for vernalization insensitivity in einkorn wheat. The mvp mutation resulted from deletion of the VRN1 coding and promoter regions, demonstrating that WAP1/VRN1 is an indispensable gene for phase transition in wheat. Expression analysis of flowering-related genes in mvp plants indicated that wheat GIGANTIA (GI), CONSTANS (CO) and SUPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) genes either act upstream of or in a different pathway to WAP1/VRN1

  7. A dominant negative mutant of TLK1 causes chromosome missegregation and aneuploidy in normal breast epithelial cells

    Directory of Open Access Journals (Sweden)

    Williams Briana

    2003-10-01

    Full Text Available Abstract Background In Arabidopsis thaliana, the gene Tousled encodes a protein kinase of unknown function, but mutations in the gene lead to flowering and leaf morphology defects. We have recently cloned a mammalian Tousled-Like Kinase (TLK1B and found that it phosphorylates specifically histone H3, in vitro and in vivo. We now report the effects that overexpression of a kinase-dead mutant of TLK1B mediates in a normal diploid cell line. Results Expression of a kinase-dead mutant resulted in reduction of phosphorylated histone H3, which could have consequences in mitotic segregation of chromosomes. When analyzed by FACS and microscopy, these cells displayed high chromosome number instability and aneuploidy. This phenomenon was accompanied by less condensed chromosomes at mitosis; failure of a number of chromosomes to align properly on the metaphase plate; failure of some chromosomes to attach to microtubules; and the occasional presentation of two bipolar spindles. We also used a different method (siRNA to reduce the level of endogenous TLK1, but in this case, the main result was a strong block of cell cycle progression suggesting that TLK1 may also play a role in progression from G1. This block in S phase progression could also offer a different explanation of some of the later mitotic defects. Conclusions TLK1 has a function important for proper chromosome segregation and maintenance of diploid cells at mitosis in mammalian cells that could be mediated by reduced phosphorylation of histone H3 and condensation of chromosomes, although other explanations to the phenotype are possible.

  8. Mutations in the Caenorhabditis elegans orthologs of human genes required for mitochondrial tRNA modification cause similar electron transport chain defects but different nuclear responses.

    Science.gov (United States)

    Navarro-González, Carmen; Moukadiri, Ismaïl; Villarroya, Magda; López-Pascual, Ernesto; Tuck, Simon; Armengod, M-Eugenia

    2017-07-01

    Several oxidative phosphorylation (OXPHOS) diseases are caused by defects in the post-transcriptional modification of mitochondrial tRNAs (mt-tRNAs). Mutations in MTO1 or GTPBP3 impair the modification of the wobble uridine at position 5 of the pyrimidine ring and cause heart failure. Mutations in TRMU affect modification at position 2 and cause liver disease. Presently, the molecular basis of the diseases and why mutations in the different genes lead to such different clinical symptoms is poorly understood. Here we use Caenorhabditis elegans as a model organism to investigate how defects in the TRMU, GTPBP3 and MTO1 orthologues (designated as mttu-1, mtcu-1, and mtcu-2, respectively) exert their effects. We found that whereas the inactivation of each C. elegans gene is associated with a mild OXPHOS dysfunction, mutations in mtcu-1 or mtcu-2 cause changes in the expression of metabolic and mitochondrial stress response genes that are quite different from those caused by mttu-1 mutations. Our data suggest that retrograde signaling promotes defect-specific metabolic reprogramming, which is able to rescue the OXPHOS dysfunction in the single mutants by stimulating the oxidative tricarboxylic acid cycle flux through complex II. This adaptive response, however, appears to be associated with a biological cost since the single mutant worms exhibit thermosensitivity and decreased fertility and, in the case of mttu-1, longer reproductive cycle. Notably, mttu-1 worms also exhibit increased lifespan. We further show that mtcu-1; mttu-1 and mtcu-2; mttu-1 double mutants display severe growth defects and sterility. The animal models presented here support the idea that the pathological states in humans may initially develop not as a direct consequence of a bioenergetic defect, but from the cell's maladaptive response to the hypomodification status of mt-tRNAs. Our work highlights the important association of the defect-specific metabolic rewiring with the pathological phenotype

  9. Selective chaperone effect of aminocyclitol derivatives on G202R and other mutant glucocerebrosidases causing Gaucher disease.

    Science.gov (United States)

    Serra-Vinardell, Jenny; Díaz, Lucía; Gutiérrez-de Terán, Hugo; Sánchez-Ollé, Gessamí; Bujons, Jordi; Michelakakis, Helen; Mavridou, Irene; Aerts, Johannes M F G; Delgado, Antonio; Grinberg, Daniel; Vilageliu, Lluïsa; Casas, Josefina

    2014-09-01

    Gaucher disease is an autosomal recessive lysosomal disorder characterized by the accumulation of glucosylceramide as a result of a deficiency of the enzyme glucocerebrosidase. Several competitive glucocerebrosidase inhibitors are able to act as pharmacological chaperones for an efficient rescue of the mutated, misfolded forms of the enzyme. Along this line, we report in this work on the ability of several aminocyclitols to increase the residual glucocerebrosidase activity in patient fibroblasts with different genotypes. Some of the compounds were slightly active on fibroblasts bearing some mutations, including the highly prevalent N370S mutation. All compounds were highly active as enzyme activity enhancers on fibroblasts from Gaucher disease patients containing the G202R mutation. Moreover, using the novel tagged sphingolipid ω-azidosphingosine, a reduction in the tagged glucosylceramide accumulation was also observed for selected aminocyclitols. Attempts to explain the activity impairment observed in glucocerebrosidase bearing the G202R mutation by comparative molecular dynamic studies on wild type and the G202R mutated proteins (free and isofagomine-bound, in both cases) were unsuccessful. Under the simulation conditions used, no clear effect of the G202R mutation neither over the global structure of the protein nor on the loops that constitute the glucocerebrosidase active site was observed. Since the G202R residue is located on the protein surface, altered protein-membrane or protein-protein interactions could account for the observed differences. In conclusion, we have tested novel compounds that have shown some chaperone effect on particular glucocerebrosidase mutant enzymes, supporting the enhancement therapy as an alternative approach for Gaucher disease. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Synthetic Cannabinoid Abuse and a Rare Alpha-1-Antitrypsin Mutant Causing Acute Fulminant Hepatitis: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Kurt J. Knowles

    2017-01-01

    Full Text Available Synthetic cannabinoids (SCs abuse is on the rise because they are easily obtained over the counter; they are potent psychoactive compounds and routine drug testing does not detect them. As their abuse is on the rise, so are their detrimental side effects; however, the occurrence of acute hepatitis due to SCs abuse has been reported only once before. In this case, testing revealed that the patient was also heterozygous for alpha-1-antitrypsin (A-1-AT with the phenotype of PI⁎EM. This mutant phenotype has never been reported as a cause of A-1-AT disease and the abuse of SCs in a patient with this phenotype has also never been reported. This case illustrates the possible need to expand routine drug testing for SCs and consider A-1-AT phenotyping in certain clinical scenarios.

  11. Triose phosphate isomerase deficiency is caused by altered dimerization--not catalytic inactivity--of the mutant enzymes.

    Directory of Open Access Journals (Sweden)

    Markus Ralser

    Full Text Available Triosephosphate isomerase (TPI deficiency is an autosomal recessive disorder caused by various mutations in the gene encoding the key glycolytic enzyme TPI. A drastic decrease in TPI activity and an increased level of its substrate, dihydroxyacetone phosphate, have been measured in unpurified cell extracts of affected individuals. These observations allowed concluding that the different mutations in the TPI alleles result in catalytically inactive enzymes. However, despite a high occurrence of TPI null alleles within several human populations, the frequency of this disorder is exceptionally rare. In order to address this apparent discrepancy, we generated a yeast model allowing us to perform comparative in vivo analyses of the enzymatic and functional properties of the different enzyme variants. We discovered that the majority of these variants exhibit no reduced catalytic activity per se. Instead, we observed, the dimerization behavior of TPI is influenced by the particular mutations investigated, and by the use of a potential alternative translation initiation site in the TPI gene. Additionally, we demonstrated that the overexpression of the most frequent TPI variant, Glu104Asp, which displays altered dimerization features, results in diminished endogenous TPI levels in mammalian cells. Thus, our results reveal that enzyme deregulation attributable to aberrant dimerization of TPI, rather than direct catalytic inactivation of the enzyme, underlies the pathogenesis of TPI deficiency. Finally, we discovered that yeast cells expressing a TPI variant exhibiting reduced catalytic activity are more resistant against oxidative stress caused by the thiol-oxidizing reagent diamide. This observed advantage might serve to explain the high allelic frequency of TPI null alleles detected among human populations.

  12. Lipid binding defects and perturbed synaptogenic activity of a Collybistin R290H mutant that causes epilepsy and intellectual disability.

    Science.gov (United States)

    Papadopoulos, Theofilos; Schemm, Rudolf; Grubmüller, Helmut; Brose, Nils

    2015-03-27

    Signaling at nerve cell synapses is a key determinant of proper brain function, and synaptic defects--or synaptopathies--are at the basis of many neurological and psychiatric disorders. In key areas of the mammalian brain, such as the hippocampus or the basolateral amygdala, the clustering of the scaffolding protein Gephyrin and of γ-aminobutyric acid type A receptors at inhibitory neuronal synapses is critically dependent upon the brain-specific guanine nucleotide exchange factor Collybistin (Cb). Accordingly, it was discovered recently that an R290H missense mutation in the diffuse B-cell lymphoma homology domain of Cb, which carries the guanine nucleotide exchange factor activity, leads to epilepsy and intellectual disability in human patients. In the present study, we determined the mechanism by which the Cb(R290H) mutation perturbs inhibitory synapse formation and causes brain dysfunction. Based on a combination of biochemical, cell biological, and molecular dynamics simulation approaches, we demonstrate that the R290H mutation alters the strength of intramolecular interactions between the diffuse B-cell lymphoma homology domain and the pleckstrin homology domain of Cb. This defect reduces the phosphatidylinositol 3-phosphate binding affinity of Cb, which limits its normal synaptogenic activity. Our data indicate that impairment of the membrane lipid binding activity of Cb and a consequent defect in inhibitory synapse maturation represent a likely molecular pathomechanism of epilepsy and mental retardation in humans. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  13. A quantum molecular similarity analysis of changes in molecular electron density caused by basis set flotation and electric field application

    Science.gov (United States)

    Simon, Sílvia; Duran, Miquel

    1997-08-01

    Quantum molecular similarity (QMS) techniques are used to assess the response of the electron density of various small molecules to application of a static, uniform electric field. Likewise, QMS is used to analyze the changes in electron density generated by the process of floating a basis set. The results obtained show an interrelation between the floating process, the optimum geometry, and the presence of an external field. Cases involving the Le Chatelier principle are discussed, and an insight on the changes of bond critical point properties, self-similarity values and density differences is performed.

  14. DCL2- and RDR6-dependent transitive silencing of SMXL4 and SMXL5 in Arabidopsis dcl4 mutants causes defective phloem transport and carbohydrate over-accumulation.

    Science.gov (United States)

    Wu, Yu-Yi; Hou, Bo-Han; Lee, Wen-Chi; Lu, Shin-Hua; Yang, Chen-Jui; Vaucheret, Hervé; Chen, Ho-Ming

    2017-06-01

    DICER-LIKE (DCL) enzymes process double-stranded RNA into small RNAs that act as regulators of gene expression. Arabidopsis DCL4 and DCL2 each allow the post-transcriptional gene silencing (PTGS) of viruses and transgenes, but primary PTGS-prone DCL4 outcompetes transitive PTGS-prone DCL2 in wild-type plants. This hierarchy likely prevents DCL2 having any detrimental effects on endogenous genes. Indeed, dcl4 mutants exhibit developmental defects and increased sensitivity to genotoxic stress. In this study, the mechanism underlying dcl4 defects was investigated using genetic, biochemical and high-throughput sequencing approaches. We show that the purple phenotype of dcl4 leaves correlates with carbohydrate over-accumulation and defective phloem transport, and depends on the activity of SUPPRESSOR OF GENE SILENCING 3, RNA-DEPENDENT RNA POLYMERASE 6 (RDR6) and DCL2. This phenotype correlates with the downregulation of two genes expressed in the apex and the vasculature, SMAX1-LIKE 4 (SMXL4) and SMXL5, and the accumulation of DCL2- and RDR6-dependent small interfering RNAs derived from these two genes. Supporting a causal effect, smxl4 smxl5 double mutants exhibit leaf pigmentation, enhanced starch accumulation and defective phloem transport, similar to dcl4 plants. Overall, this study elucidates the detrimental action of DCL2 when DCL4 is absent, and indicates that DCL4 outcompeting DCL2 in wild-type plants is crucial to prevent the degradation of endogenous transcripts by DCL2- and RDR6-dependent transitive PTGS. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  15. Chloroquine causes similar electroretinogram modifications, neuronal phospholipidosis and marked impairment of synaptic vesicle transport in Albino and Pigmented Rats

    International Nuclear Information System (INIS)

    Lezmi, Stéphane; Rokh, Najla; Saint-Macary, Gérard; Pino, Michael; Sallez, Valérie; Thevenard, Françoise; Roome, Nigel; Rosolen, Serge

    2013-01-01

    Retinal toxicity of chloroquine has been known for several years, but the mechanism(s) of toxicity remain controversial; some author support the idea that the binding of chloroquine to melanin pigments in the retinal pigmented epithelium (RPE) play a major toxic role by concentrating the drug in the eye. In our study, 12 albinos Sprague-Dawley (SD) and 12 pigmented Brown Norway (BN) rats were treated orally for 3 months with chloroquine to compare functional and pathological findings. On Flash electroretinograms (ERG) performed in scotopic conditions, similar and progressive (time-dependent) delayed onset and decreased amplitudes of oscillatory potentials (from Day 71) and b-waves (on Day 92) were identified in both BN and SD rats. In both strains, identical morphological changes consisted of neuronal phospholipidosis associated with UV auto-fluorescence without evidence of retinal degeneration and gliosis; the RPE did not show any morphological lesions or autofluorescence. IHC analyses demonstrated a decrease in GABA expression in the inner nuclear layer. In addition, a marked accumulation of synaptic vesicles coupled with a marked disruption of neurofilaments in the optic nerve fibers was identified. In conclusion, ERG observations were very similar to those described in humans. Comparable ERG modifications, histopathology and immunohistochemistry findings were observed in the retina of both rat strains suggesting that melanin pigment is unlikely involved. chloroquine-induced impairment of synaptic vesicle transport, likely related to disruption of neurofilaments was identified and non-previously reported. This new mechanism of toxicity may also be responsible for the burry vision described in humans chronically treated with chloroquine

  16. Chloroquine causes similar electroretinogram modifications, neuronal phospholipidosis and marked impairment of synaptic vesicle transport in albino and pigmented rats.

    Science.gov (United States)

    Lezmi, Stéphane; Rokh, Najla; Saint-Macary, Gérard; Pino, Michael; Sallez, Valérie; Thevenard, Françoise; Roome, Nigel; Rosolen, Serge

    2013-06-07

    Retinal toxicity of chloroquine has been known for several years, but the mechanism(s) of toxicity remain controversial; some author support the idea that the binding of chloroquine to melanin pigments in the retinal pigmented epithelium (RPE) play a major toxic role by concentrating the drug in the eye. In our study, 12 albinos Sprague-Dawley (SD) and 12 pigmented Brown Norway (BN) rats were treated orally for 3 months with chloroquine to compare functional and pathological findings. On Flash electroretinograms (ERG) performed in scotopic conditions, similar and progressive (time-dependent) delayed onset and decreased amplitudes of oscillatory potentials (from Day 71) and b-waves (on Day 92) were identified in both BN and SD rats. In both strains, identical morphological changes consisted of neuronal phospholipidosis associated with UV auto-fluorescence without evidence of retinal degeneration and gliosis; the RPE did not show any morphological lesions or autofluorescence. IHC analyses demonstrated a decrease in GABA expression in the inner nuclear layer. In addition, a marked accumulation of synaptic vesicles coupled with a marked disruption of neurofilaments in the optic nerve fibers was identified. In conclusion, ERG observations were very similar to those described in humans. Comparable ERG modifications, histopathology and immunohistochemistry findings were observed in the retina of both rat strains suggesting that melanin pigment is unlikely involved. chloroquine-induced impairment of synaptic vesicle transport, likely related to disruption of neurofilaments was identified and non-previously reported. This new mechanism of toxicity may also be responsible for the burry vision described in humans chronically treated with chloroquine. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  17. Development and Parameters of a Non-Self-Similar CME Caused by the Eruption of a Quiescent Prominence

    Science.gov (United States)

    Kuzmenko, I. V.; Grechnev, V. V.

    2017-10-01

    The eruption of a large quiescent prominence on 17 August 2013 and an associated coronal mass ejection (CME) were observed from different vantage points by the Solar Dynamics Observatory (SDO), the Solar-Terrestrial Relations Observatory (STEREO), and the Solar and Heliospheric Observatory (SOHO). Screening of the quiet Sun by the prominence produced an isolated negative microwave burst. We estimated the parameters of the erupting prominence from a radio absorption model and measured them from 304 Å images. The variations of the parameters as obtained by these two methods are similar and agree within a factor of two. The CME development was studied from the kinematics of the front and different components of the core and their structural changes. The results were verified using movies in which the CME expansion was compensated for according to the measured kinematics. We found that the CME mass (3.6 × 10^{15} g) was mainly supplied by the prominence (≈ 6 × 10^{15} g), while a considerable part drained back. The mass of the coronal-temperature component did not exceed 10^{15} g. The CME was initiated by the erupting prominence, which constituted its core and remained active. The structural and kinematical changes started in the core and propagated outward. The CME structures continued to form during expansion, which did not become self-similar up to 25 R_{⊙}. The aerodynamic drag was insignificant. The core formed during the CME rise to 4 R_{⊙} and possibly beyond. Some of its components were observed to straighten and stretch outward, indicating the transformation of tangled structures of the core into a simpler flux rope, which grew and filled the cavity as the CME expanded.

  18. Phenotypic and genetic analysis of Lymantria dispar nucleopolyhedrovirus few polyhedra mutants: Mutations in the 25K FP gene may be caused by DNA replication errors

    Science.gov (United States)

    David S. Bischoff; James M. Slavicek

    1997-01-01

    We previously demonstrated that polyhedron formation (PF) mutants arise at a high frequency during serial passage of the Lymantria dispar nucleopolyhedrovirus (LdMNPV) in the L. dispar 652Y cell line (J.M. Slavicek, N. Hayes-Plazolles, and M.E. Kelly, Biol. Control 5:251-261, 1995). Most of these PF mutants...

  19. Investigation report on causes of radiation underexposure accident at Yamagata University Hospital and Prevention of Similar accident

    International Nuclear Information System (INIS)

    2005-01-01

    The accident in the title was announced on February 18, 2004 by the hospital, which asked its investigation immediately. The group based on 4 academic societies concerned, thereby started investigations of the in-house reports on the accident and of subsequent hospital visit in March, which involved hearing from personnel concerned, physical/technological examinations and clinical evaluation, with respect to the hospital system for radiation treatment, flow of the treatment, accident details, estimation of the actual expose dose and classification of patients. The investigational group found for the actual number of patients underexposed to be 36 (63, in the in-house report) in 1,377. The cause of the accident was thought essentially the input error for the correct power coefficient 1.032 to be a wrong one 1.320 for 15 x 15 cm 4 MV X-ray. The error had been overlooked by the contract operator from the introduction of the treatment planning equipment in 1999. For prevention, setting up of quality assurance (QA) program by the hospital, the user itself, was pointed out necessary. Making the guideline for introducing the new equipment was conceivably an important work of the trader. (N.I.)

  20. Increased alcohol consumption as a cause of alcoholism, without similar evidence for depression: a Mendelian randomization study.

    Science.gov (United States)

    Wium-Andersen, Marie Kim; Ørsted, David Dynnes; Tolstrup, Janne Schurmann; Nordestgaard, Børge Grønne

    2015-04-01

    Increased alcohol consumption has been associated with depression and alcoholism, but whether these associations are causal remains unclear. We tested whether alcohol consumption is causally associated with depression and alcoholism. We included 78,154 men and women aged 20-100 years randomly selected in 1991-2010 from the general population of Copenhagen, Denmark, and genotyped 68,486 participants for two genetic variants in two alcohol dehydrogenase (ADH) genes, ADH-1B (rs1229984) and ADH-1C (rs698). We performed observational and causal analyses using a Mendelian randomization design with antidepressant medication use and hospitalization/death, with depression and alcoholism as outcomes. In prospective analyses, the multifactorially adjusted hazard ratio for participants reporting >6 drinks/day vs participants reporting 0.1-1 drinks/day was 1.28 (95% confidence interval, 1.00-1.65) for prescription antidepressant use, with a corresponding hazard ratio of 0.80 (0.45-1.45) for hospitalization/death with depression and of 11.7 (8.77-15.6) for hospitalization/death with alcoholism. For hospitalization/death with alcoholism, instrumental variable analysis yielded a causal odds ratio of 28.6 (95 % confidence interval 6.47-126) for an increase of 1 drink/day estimated from the combined genotype combination, whereas the corresponding multifactorially adjusted observational odds ratio was 1.28 (1.25-1.31). Corresponding odds ratios were 1.11 (0.67-1.83) causal and 1.04 (1.03-1.06) observational for prescription antidepressant use, and 4.52 (0.99-20.5) causal and 0.98 (0.94-1.03) observational for hospitalization/death with depression. These data indicate that the association between increased alcohol consumption and alcoholism is causal, without similar strong evidence for depression. © The Author 2014; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

  1. Newcastle Disease Viruses Causing Recent Outbreaks Worldwide Show Unexpectedly High Genetic Similarity to Historical Virulent Isolates from the 1940s

    Science.gov (United States)

    Dimitrov, Kiril M.; Lee, Dong-Hun; Williams-Coplin, Dawn; Olivier, Timothy L.; Miller, Patti J.

    2016-01-01

    Virulent strains of Newcastle disease virus (NDV) cause Newcastle disease (ND), a devastating disease of poultry and wild birds. Phylogenetic analyses clearly distinguish historical isolates (obtained prior to 1960) from currently circulating viruses of class II genotypes V, VI, VII, and XII through XVIII. Here, partial and complete genomic sequences of recent virulent isolates of genotypes II and IX from China, Egypt, and India were found to be nearly identical to those of historical viruses isolated in the 1940s. Phylogenetic analysis, nucleotide distances, and rates of change demonstrate that these recent isolates have not evolved significantly from the most closely related ancestors from the 1940s. The low rates of change for these virulent viruses (7.05 × 10−5 and 2.05 × 10−5 per year, respectively) and the minimal genetic distances existing between these and historical viruses (0.3 to 1.2%) of the same genotypes indicate an unnatural origin. As with any other RNA virus, Newcastle disease virus is expected to evolve naturally; thus, these findings suggest that some recent field isolates should be excluded from evolutionary studies. Furthermore, phylogenetic analyses show that these recent virulent isolates are more closely related to virulent strains isolated during the 1940s, which have been and continue to be used in laboratory and experimental challenge studies. Since the preservation of viable viruses in the environment for over 6 decades is highly unlikely, it is possible that the source of some of the recent virulent viruses isolated from poultry and wild birds might be laboratory viruses. PMID:26888902

  2. Characteristics of the repair - deficient mutants 1435 plague microbe strain

    International Nuclear Information System (INIS)

    Temiralieva, G.A.

    1977-01-01

    Repair-deficient mutants 1435 A uvr - hcr - , 1435-17 uvr - hcr + and 1435-35 lon have been obtained from 1435 plague microbe strain, isolated from a large gerbil living in the Central Asian desert region. The mutants have the same cultural-morphological and enzymatic characteristics, the same need in growth factors and similar virulence determinants as the original strain, but they do not cause death of the experimental animals

  3. Hyperactivity of the Arabidopsis cryptochrome (cry1) L407F mutant is caused by a structural alteration close to the cry1 ATP-binding site.

    Science.gov (United States)

    Orth, Christian; Niemann, Nils; Hennig, Lars; Essen, Lars-Oliver; Batschauer, Alfred

    2017-08-04

    Plant cryptochromes (cry) act as UV-A/blue light receptors. The prototype, Arabidopsis thaliana cry1, regulates several light responses during the life cycle, including de-etiolation, and is also involved in regulating flowering time. The cry1 photocycle is initiated by light absorption by its FAD chromophore, which is most likely fully oxidized (FAD ox ) in the dark state and photoreduced to the neutral flavin semiquinone (FADH°) in its lit state. Cryptochromes lack the DNA-repair activity of the closely related DNA photolyases, but they retain the ability to bind nucleotides such as ATP. The previously characterized L407F mutant allele of Arabidopsis cry1 is biologically hyperactive and seems to mimic the ATP-bound state of cry1, but the reason for this phenotypic change is unclear. Here, we show that cry1 L407F can still bind ATP, has less pronounced photoreduction and formation of FADH° than wild-type cry1, and has a dark reversion rate 1.7 times lower than that of the wild type. The hyperactivity of cry1 L407F is not related to a higher FADH° occupancy of the photoreceptor but is caused by a structural alteration close to the ATP-binding site. Moreover, we show that ATP binds to cry1 in both the dark and the lit states. This binding was not affected by cry1's C-terminal extension, which is important for signal transduction. Finally, we show that a recently discovered chemical inhibitor of cry1, 3-bromo-7-nitroindazole, competes for ATP binding and thereby diminishes FADH° formation, which demonstrates that both processes are important for cry1 function. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  4. Amino alcohol- (NPS-2143 and quinazolinone-derived calcilytics (ATF936 and AXT914 differentially mitigate excessive signalling of calcium-sensing receptor mutants causing Bartter syndrome Type 5 and autosomal dominant hypocalcemia.

    Directory of Open Access Journals (Sweden)

    Saskia Letz

    Full Text Available Activating calcium sensing receptor (CaSR mutations cause autosomal dominant hypocalcemia (ADH characterized by low serum calcium, inappropriately low PTH and relative hypercalciuria. Four activating CaSR mutations cause additional renal wasting of sodium, chloride and other salts, a condition called Bartter syndrome (BS type 5. Until today there is no specific medical treatment for BS type 5 and ADH. We investigated the effects of different allosteric CaSR antagonists (calcilytics on activating CaSR mutants.All 4 known mutations causing BS type 5 and five ADH mutations were expressed in HEK 293T cells and receptor signalling was studied by measurement of intracellular free calcium in response to extracellular calcium ([Ca2+]o. To investigate the effect of calcilytics, cells were stimulated with 3 mM [Ca2+]o in the presence or absence of NPS-2143, ATF936 or AXT914.All BS type 5 and ADH mutants showed enhanced signalling activity to [Ca2+]o with left shifted dose response curves. In contrast to the amino alcohol NPS-2143, which was only partially effective, the quinazolinone calcilytics ATF936 and AXT914 significantly mitigated excessive cytosolic calcium signalling of all BS type 5 and ADH mutants studied. When these mutants were co-expressed with wild-type CaSR to approximate heterozygosity in patients, ATF936 and AXT914 were also effective on all mutants.The calcilytics ATF936 and AXT914 are capable of attenuating enhanced cytosolic calcium signalling activity of CaSR mutations causing BS type 5 and ADH. Quinazolinone calcilytics might therefore offer a novel treatment option for patients with activating CaSR mutations.

  5. Isozyme differences in barley mutants

    Energy Technology Data Exchange (ETDEWEB)

    AI-Jibouri, A A.M.; Dham, K M [Department of Botany, Nuclear Research Centre, Baghdad (Iraq)

    1990-01-01

    Full text: Thirty mutants (M{sub 11}) of barley (Hordeum vulgare L.) induced by physical and chemical mutagens were analysed for isozyme composition using polyacrylamide gel electrophoresis. Results show that these mutants were different in the isozymes leucine aminopeptidase, esterase and peroxidase. The differences included the number of forms of each enzyme, relative mobility value and their intensity on the gel. Glutamate oxaloacetate transaminase isozyme was found in six molecular forms and these forms were similar in all mutants. (author)

  6. Isozyme differences in barley mutants

    International Nuclear Information System (INIS)

    AI-Jibouri, A.A.M.; Dham, K.M.

    1990-01-01

    Full text: Thirty mutants (M 11 ) of barley (Hordeum vulgare L.) induced by physical and chemical mutagens were analysed for isozyme composition using polyacrylamide gel electrophoresis. Results show that these mutants were different in the isozymes leucine aminopeptidase, esterase and peroxidase. The differences included the number of forms of each enzyme, relative mobility value and their intensity on the gel. Glutamate oxaloacetate transaminase isozyme was found in six molecular forms and these forms were similar in all mutants. (author)

  7. Defective nucleolar localization and dominant interfering properties of a parafibromin L95P missense mutant causing the hyperparathyroidism-jaw tumor syndrome

    Science.gov (United States)

    Panicker, Leelamma M.; Zhang, Jian-Hua; Dagur, Pradeep K.; Gastinger, Matthew J.; Simonds, William F.

    2011-01-01

    The hyperparathyroidism-jaw tumor syndrome (HPT-JT) is a familial cancer syndrome that can result from germline inactivation of HRPT2/CDC73, a putative tumor suppressor gene that encodes parafibromin, a component of the transcriptional regulatory PAF1 complex with homology to the yeast protein Cdc73p. The vast majority of HRPT2/CDC73 germline mutations identified have been truncation or frameshift mutations, and loss-of-function due to missense mutation is rare. We report here a kindred with HPT-JT due to a germline L95P missense mutation in parafibromin. The mutant parafibromin was studied in vitro to understand the basis of its presumed loss-of-function. When transfected in cultured cells the L95P mutant was expressed to a lower level than wild-type parafibromin, a difference that was not overcome by inhibition of the proteasome degradation pathway. The L95P mutant parafibromin retained the ability to assemble with endogenous PAF1 complex components as evidenced by co-immunoprecipitation. Analysis of subcellular localization showed that the L95P mutant was markedly deficient in nucleolar localization compared to the wild-type, an impairment likely resulting from disruption of a putative nucleolar localization signal immediately upstream of the L95P mutation. Transfection of the L95P parafibromin mutant, but not the wild type, enhanced cell-cycle progression and increased cell survival in NIH-3T3 and HEK 293 cells, resulting apparently from dominant interference with endogenous parafibromin action. The simultaneous loss of nucleolar localization and acquisition of a growth stimulatory phenotype with the L95P mutation raise the possibility that parafibromin must interact with targets in the nucleolus to fully execute its tumor suppressor functions. PMID:20304979

  8. Botulinum neurotoxin G binds synaptotagmin-II in a mode similar to that of serotype B: tyrosine 1186 and lysine 1191 cause its lower affinity.

    Science.gov (United States)

    Willjes, Gesche; Mahrhold, Stefan; Strotmeier, Jasmin; Eichner, Timo; Rummel, Andreas; Binz, Thomas

    2013-06-04

    Botulinum neurotoxins (BoNTs) block neurotransmitter release by proteolyzing SNARE proteins in peripheral nerve terminals. Entry into neurons occurs subsequent to interaction with gangliosides and a synaptic vesicle protein. Isoforms I and II of synaptotagmin were shown to act as protein receptors for two of the seven BoNT serotypes, BoNT/B and BoNT/G, and for mosaic-type BoNT/DC. BoNT/B and BoNT/G exhibit a homologous binding site for synaptotagmin whose interacting part adopts helical structure upon binding to BoNT/B. Whereas the BoNT/B-synaptotagmin-II interaction has been elucidated in molecular detail, corresponding information about BoNT/G is lacking. Here we systematically mutated the synaptotagmin binding site in BoNT/G and performed a comparative binding analysis with mutants of the cell binding subunit of BoNT/B. The results suggest that synaptotagmin takes the same overall orientation in BoNT/B and BoNT/G governed by the strictly conserved central parts of the toxins' binding site. The surrounding nonconserved areas differently contribute to receptor binding. Reciprocal mutations Y1186W and L1191Y increased the level of binding of BoNT/G approximately to the level of BoNT/B affinity, suggesting a similar synaptotagmin-bound state. The effects of the mutations were confirmed by studying the activity of correspondingly mutated full-length BoNTs. On the basis of these data, molecular modeling experiments were employed to reveal an atomistic model of BoNT/G-synaptotagmin recognition. These data suggest a reduced length and/or a bend in the C-terminal part of the synaptotagmin helix that forms upon contact with BoNT/G as compared with BoNT/B and are in agreement with the data of the mutational analyses.

  9. Exposure to low dose benzo[a]pyrene during early life stages causes symptoms similar to cardiac hypertrophy in adult zebrafish.

    Science.gov (United States)

    Huang, Lixing; Gao, Dongxu; Zhang, Youyu; Wang, Chonggang; Zuo, Zhenghong

    2014-07-15

    Growing evidence indicates that polycyclic aromatic hydrocarbons (PAHs) can lead to cardiac hypertrophy and recent research indicates that exposure to low dose crude oil during early embryonic development may lead to impacts on heart health at later life stages. The aim of this study was to evaluate whether exposure during early life stages to low dose benzo[a]pyrene (BaP), as a high-ring PAH, would lead to cardiac hypertrophy at later life stages. Zebrafish were exposed to low dose BaP until 96 hpf, then transferred to clean water and maintained for a year before histological and molecular biological analysis. Our results showed that exposure to low level BaP during early life stages increased heart weight to body weight ratios and deposited collagen in the heart of adult zebrafish. ANP, BNP and c-Myc were also induced in the heart of adult zebrafish by BaP. These results proved that low level BaP exposure during early life stages caused symptoms similar to cardiac hypertrophy in adult zebrafish. Our results displayed an elevated expression of CdC42, RhoA, p-ERK1, 2 and Rac1. Therefore, the mechanism of the cardiac hypertrophy caused by BaP exposure during early life stages may be through inducing the expression of CdC42, RhoA and Rac1, together with activating ERK1, 2. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Liver tumor formation by a mutant retinoblastoma protein in the transgenic mice is caused by an upregulation of c-Myc target genes

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Bo; Hikosaka, Keisuke; Sultana, Nishat; Sharkar, Mohammad Tofael Kabir [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Noritake, Hidenao [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Kimura, Wataru; Wu, Yi-Xin [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Kobayashi, Yoshimasa [Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Uezato, Tadayoshi [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Miura, Naoyuki, E-mail: nmiura@hama-med.ac.jp [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan)

    2012-01-06

    Highlights: Black-Right-Pointing-Pointer Fifty percent of the mutant Rb transgenic mice produced liver tumors. Black-Right-Pointing-Pointer In the tumor, Foxm1, Skp2, Bmi1 and AP-1 mRNAs were up-regulated. Black-Right-Pointing-Pointer No increase in expression of the Myc-target genes was observed in the non-tumorous liver. Black-Right-Pointing-Pointer Tumor formation depends on up-regulation of the Myc-target genes. -- Abstract: The retinoblastoma (Rb) tumor suppressor encodes a nuclear phosphoprotein that regulates cellular proliferation, apoptosis and differentiation. In order to adapt itself to these biological functions, Rb is subjected to modification cycle, phosphorylation and dephosphorylation. To directly determine the effect of phosphorylation-resistant Rb on liver development and function, we generated transgenic mice expressing phosphorylation-resistant human mutant Rb (mt-Rb) under the control of the rat hepatocyte nuclear factor-1 gene promoter/enhancer. Expression of mt-Rb in the liver resulted in macroscopic neoplastic nodules (adenomas) with {approx}50% incidence within 15 months old. Interestingly, quantitative reverse transcriptase-PCR analysis showed that c-Myc was up-regulated in the liver of mt-Rb transgenic mice irrespective of having tumor tissues or no tumor. In tumor tissues, several c-Myc target genes, Foxm1, c-Jun, c-Fos, Bmi1 and Skp2, were also up-regulated dramatically. We determined whether mt-Rb activated the Myc promoter in the HTP9 cells and demonstrated that mt-Rb acted as an inhibitor of wild-type Rb-induced repression on the Myc promoter. Our results suggest that continued upregulation of c-Myc target genes promotes the liver tumor formation after about 1 year of age.

  11. Connexin mutants and cataracts

    Directory of Open Access Journals (Sweden)

    Eric C Beyer

    2013-04-01

    Full Text Available The lens is a multicellular, but avascular tissue that must stay transparent to allow normal transmission of light and focusing of it on the retina. Damage to lens cells and/or proteins can cause cataracts, opacities that disrupt these processes. The normal survival of the lens is facilitated by an extensive network of gap junctions formed predominantly of connexin46 and connexin50. Mutations of the genes that encode these connexins (GJA3 and GJA8 have been identified and linked to inheritance of cataracts in human families and mouse lines. In vitro expression studies of several of these mutants have shown that they exhibit abnormalities that may lead to disease. Many of the mutants reduce or modify intercellular communication due to channel alterations (including loss of function or altered gating or due to impaired cellular trafficking which reduces the number of gap junction channels within the plasma membrane. However, the abnormalities detected in studies of other mutants suggest that they cause cataracts through other mechanisms including gain of hemichannel function (leading to cell injury and death and formation of cytoplasmic accumulations (that may act as light scattering particles. These observations and the anticipated results of ongoing studies should elucidate the mechanisms of cataract development due to mutations of lens connexins and abnormalities of other lens proteins. They may also contribute to our understanding of the mechanisms of disease due to connexin mutations in other tissues.

  12. A Novel Leu92 Mutant of HIV-1 Reverse Transcriptase with a Selective Deficiency in Strand Transfer Causes a Loss of Viral Replication.

    Science.gov (United States)

    Herzig, Eytan; Voronin, Nickolay; Kucherenko, Nataly; Hizi, Amnon

    2015-08-01

    The process of reverse transcription (RTN) in retroviruses is essential to the viral life cycle. This key process is catalyzed exclusively by the viral reverse transcriptase (RT) that copies the viral RNA into DNA by its DNA polymerase activity, while concomitantly removing the original RNA template by its RNase H activity. During RTN, the combination between DNA synthesis and RNA hydrolysis leads to strand transfers (or template switches) that are critical for the completion of RTN. The balance between these RT-driven activities was considered to be the sole reason for strand transfers. Nevertheless, we show here that a specific mutation in HIV-1 RT (L92P) that does not affect the DNA polymerase and RNase H activities abolishes strand transfer. There is also a good correlation between this complete loss of the RT's strand transfer to the loss of the DNA clamp activity of the RT, discovered recently by us. This finding indicates a mechanistic linkage between these two functions and that they are both direct and unique functions of the RT (apart from DNA synthesis and RNA degradation). Furthermore, when the RT's L92P mutant was introduced into an infectious HIV-1 clone, it lost viral replication, due to inefficient intracellular strand transfers during RTN, thus supporting the in vitro data. As far as we know, this is the first report on RT mutants that specifically and directly impair RT-associated strand transfers. Therefore, targeting residue Leu92 may be helpful in selectively blocking this RT activity and consequently HIV-1 infectivity and pathogenesis. Reverse transcription in retroviruses is essential for the viral life cycle. This multistep process is catalyzed by viral reverse transcriptase, which copies the viral RNA into DNA by its DNA polymerase activity (while concomitantly removing the RNA template by its RNase H activity). The combination and balance between synthesis and hydrolysis lead to strand transfers that are critical for reverse transcription

  13. Leaf and canopy photosynthesis of a chlorophyll deficient soybean mutant.

    Science.gov (United States)

    Sakowska, Karolina; Alberti, Giorgio; Genesio, Lorenzo; Peressotti, Alessandro; Delle Vedove, Gemini; Gianelle, Damiano; Colombo, Roberto; Rodeghiero, Mirco; Panigada, Cinzia; Juszczak, Radosław; Celesti, Marco; Rossini, Micol; Haworth, Matthew; Campbell, Benjamin W; Mevy, Jean-Philippe; Vescovo, Loris; Cendrero-Mateo, M Pilar; Rascher, Uwe; Miglietta, Franco

    2018-03-02

    The photosynthetic, optical, and morphological characteristics of a chlorophyll-deficient (Chl-deficient) "yellow" soybean mutant (MinnGold) were examined in comparison with 2 green varieties (MN0095 and Eiko). Despite the large difference in Chl content, similar leaf photosynthesis rates were maintained in the Chl-deficient mutant by offsetting the reduced absorption of red photons by a small increase in photochemical efficiency and lower non-photochemical quenching. When grown in the field, at full canopy cover, the mutants reflected a significantly larger proportion of incoming shortwave radiation, but the total canopy light absorption was only slightly reduced, most likely due to a deeper penetration of light into the canopy space. As a consequence, canopy-scale gross primary production and ecosystem respiration were comparable between the Chl-deficient mutant and the green variety. However, total biomass production was lower in the mutant, which indicates that processes other than steady state photosynthesis caused a reduction in biomass accumulation over time. Analysis of non-photochemical quenching relaxation and gas exchange in Chl-deficient and green leaves after transitions from high to low light conditions suggested that dynamic photosynthesis might be responsible for the reduced biomass production in the Chl-deficient mutant under field conditions. © 2018 John Wiley & Sons Ltd.

  14. Identification of eight new mutations in familial neurogenic diabetes insipidus supports the concept that defective folding of the mutant provasopressin-neurophysin causes the disease

    Energy Technology Data Exchange (ETDEWEB)

    Rittig, S.; Siggaard, C.; Pedersen, E.B. [University Hospital in Aarhus (Denmark)] [and others

    1994-09-01

    Familial neurogenic diabetes insipidus (FNDI) is an autosomal dominant disorder with a uniform phenotype characterized by polyuria, polydipsia and a severe deficiency of arginine vasopressin (AVP). These abnormalities develop postnatally and appear to be due to progressive degeneration of AVP producing neurons. Previous studies in 8 FNDI kindreds have identified 5 different mutations in the gene that codes for the AVP-neurophysin (NP) precursor, AVP-NP. Four kindreds had the same missense mutation in the part of exon 1 that codes for the C-terminal amino acid of the signal peptide (SP). The other 4 had different missense mutations or a codon deletion in exon 2 which codes for the highly conserved part of NP. In the present study, the AVP-NP genes from 8 other kindreds with FNDI were sequenced bidirectionally using sequence and single-stranded DNA amplified by PCR with biotinylated primers flanking each of the 3 exons. We find that each of the 8 kindreds has a different, previously unreported mutation in either the SP coding part of exon 1, in exon 2 or in the variable, NP-coding part of exon 3. Combining these 8 new mutations with the 5 described previously reveals a distribution pattern that corresponds closely to the domains involved in the mutually interactive processes of AVP binding, folding and dimerization of NP. Based on these findings and the clinical features of FNDI, we postulate that the precursors produced by the mutant alleles are cytotoxic because they do not fold or dimerize properly for subsequent packaging and processing.

  15. Polyacrylate/nanosilica causes pleural and pericardial effusion, and pulmonary fibrosis and granuloma in rats similar to those observed in exposed workers.

    Science.gov (United States)

    Zhu, Xiaoli; Cao, Wen; Chang, Bing; Zhang, Linyuan; Qiao, Peihuan; Li, Xue; Si, Lifang; Niu, Yingmei; Song, Yuguo

    2016-01-01

    Nanomaterials offer great benefit as well as potential damage to humans. Workers exposed to polyacrylate coatings have pleural effusion, pericardial effusion, and pulmonary fibrosis and granuloma, which are thought to be related to the high exposure to nanomaterials in the coatings. The study aimed to determine whether polyacrylate/silica nanoparticles cause similar toxicity in rats, as observed in exposed workers. Ninety male Wistar rats were randomly divided into five groups with 18 rats in each group. The groups included the saline control group, another control group of polyacrylate only, and low-, intermediate-, and high-dose groups of polyacrylate/nanosilica with concentrations of 3.125, 6.25, and 12.5 mg/kg. Seventy-five rats for the 1-week study were terminated for scheduled necropsy at 24 hours, 3 days, and 7 days postintratracheal instillation. The remaining 15 rats (three males/group) had repeated ultrasound and chest computed tomography examinations in a 2-week study to observe the pleural and pericardial effusion and pulmonary toxicity. We found that polyacrylate/nanosilica resulted in pleural and pericardial effusions, where nanosilica was isolated and detected. Effusion occurred on day 3 and day 5 post-administration of nanocomposites in the 6.25 and 12.5 mg/kg groups, it gradually rose to a maximum on days 7-10 and then slowly decreased and disappeared on day 14. With an increase in polyacrylate/nanosilica concentrations, pleural effusion increased, as shown by ultrasonographic qualitative observations. Pulmonary fibrosis and granuloma were also observed in the high-dose polyacrylate/nanosilica group. Our study shows that polyacrylate/nanosilica results in specific toxicity presenting as pleural and pericardial effusion, as well as pulmonary fibrosis and granuloma, which are almost identical to results in reported patients. These results indicate the urgent need and importance of nanosafety and awareness of toxicity of polyacrylate/nanosilica.

  16. Polyacrylate/nanosilica causes pleural and pericardial effusion, and pulmonary fibrosis and granuloma in rats similar to those observed in exposed workers

    Science.gov (United States)

    Zhu, Xiaoli; Cao, Wen; Chang, Bing; Zhang, Linyuan; Qiao, Peihuan; Li, Xue; Si, Lifang; Niu, Yingmei; Song, Yuguo

    2016-01-01

    Nanomaterials offer great benefit as well as potential damage to humans. Workers exposed to polyacrylate coatings have pleural effusion, pericardial effusion, and pulmonary fibrosis and granuloma, which are thought to be related to the high exposure to nanomaterials in the coatings. The study aimed to determine whether polyacrylate/silica nanoparticles cause similar toxicity in rats, as observed in exposed workers. Ninety male Wistar rats were randomly divided into five groups with 18 rats in each group. The groups included the saline control group, another control group of polyacrylate only, and low-, intermediate-, and high-dose groups of polyacrylate/nanosilica with concentrations of 3.125, 6.25, and 12.5 mg/kg. Seventy-five rats for the 1-week study were terminated for scheduled necropsy at 24 hours, 3 days, and 7 days postintratracheal instillation. The remaining 15 rats (three males/group) had repeated ultrasound and chest computed tomography examinations in a 2-week study to observe the pleural and pericardial effusion and pulmonary toxicity. We found that polyacrylate/nanosilica resulted in pleural and pericardial effusions, where nanosilica was isolated and detected. Effusion occurred on day 3 and day 5 post-administration of nanocomposites in the 6.25 and 12.5 mg/kg groups, it gradually rose to a maximum on days 7–10 and then slowly decreased and disappeared on day 14. With an increase in polyacrylate/nanosilica concentrations, pleural effusion increased, as shown by ultrasonographic qualitative observations. Pulmonary fibrosis and granuloma were also observed in the high-dose polyacrylate/nanosilica group. Our study shows that polyacrylate/nanosilica results in specific toxicity presenting as pleural and pericardial effusion, as well as pulmonary fibrosis and granuloma, which are almost identical to results in reported patients. These results indicate the urgent need and importance of nanosafety and awareness of toxicity of polyacrylate

  17. Identification of p38 MAPK and JNK as New Targets for Correction of Wilson Disease-Causing ATP7B Mutants

    NARCIS (Netherlands)

    Chesi, Giancarlo; Hegde, Ramanath N.; Iacobacci, Simona; Concilli, Mafalda; Parashuraman, Seetharaman; Festa, Beatrice Paola; Polishchuk, Elena V.; Di Tullio, Giuseppe; Carissimo, Annamaria; Montefusco, Sandro; Canetti, Diana; Monti, Maria; Amoresano, Angela; Pucci, Piero; Sluis, van de Bart; Lutsenko, Svetlana; Luini, Alberto; Polishchuk, Roman S.

    Wilson disease (WD) is an autosomal recessive disorder that is caused by the toxic accumulation of copper (Cu) in the liver. The ATP7B gene, which is mutated in WD, encodes a multitransmembrane domain adenosine triphosphatase that traffics from the trans-Golgi network to the canalicular area of

  18. Social approach behaviors are similar on conventional versus reverse lighting cycles, and in replications across cohorts, in BTBR T+ tf/J, C57BL/6J, and vasopressin receptor 1B mutant mice

    Directory of Open Access Journals (Sweden)

    Mu Yang

    2007-11-01

    Full Text Available Mice are a nocturnal species, whose social behaviors occur primarily during the dark phase of the circadian cycle. However, laboratory rodents are frequently tested during their light phase, for practical reasons. We investigated the question of whether light phase testing presents a methodological pitfall for investigating mouse social approach behaviors. Three lines of mice were systematically compared. One cohort of each line was raised in a conventional lighting schedule and tested during the light phase, under white light illumination; another cohort was raised in a reverse lighting schedule and tested during their dark phase, under dim red light. Male C57BL/6J (B6 displayed high levels of sociability in our three-chambered automated social approach task when tested in either phase. BTBR T+ tf/J (BTBR displayed low levels of sociability in either phase. Five cohorts of vasopressin receptor subtype 1b (Avpr1b null mutants, heterozygotes, and wildtype littermate controls were tested in the same social approach paradigm: three in the dark phase and two in the light phase. All three genotypes displayed normal sociability in four out of the five replications. In the juvenile play test, testing phase had no effect on play soliciting behaviors in Avpr1b mice, but had modest effects on nose sniff and huddling. Taken together, these findings indicate that testing phase is not a crucial factor for studying some forms of social approach in juvenile and adult mice.

  19. Current insights into the role of PKA phosphorylation in CFTR channel activity and the pharmacological rescue of cystic fibrosis disease-causing mutants.

    Science.gov (United States)

    Chin, Stephanie; Hung, Maurita; Bear, Christine E

    2017-01-01

    Cystic fibrosis transmembrane conductance regulator (CFTR) channel gating is predominantly regulated by protein kinase A (PKA)-dependent phosphorylation. In addition to regulating CFTR channel activity, PKA phosphorylation is also involved in enhancing CFTR trafficking and mediating conformational changes at the interdomain interfaces of the protein. The major cystic fibrosis (CF)-causing mutation is the deletion of phenylalanine at position 508 (F508del); it causes many defects that affect CFTR trafficking, stability, and gating at the cell surface. Due to the multiple roles of PKA phosphorylation, there is growing interest in targeting PKA-dependent signaling for rescuing the trafficking and functional defects of F508del-CFTR. This review will discuss the effects of PKA phosphorylation on wild-type CFTR, the consequences of CF mutations on PKA phosphorylation, and the development of therapies that target PKA-mediated signaling.

  20. Numerical Analysis of Storm Surge and Seiche at Tokyo Bay caused by the 2 Similar Typhoons, Typhoon Phanphon and Vongfong in 2014

    Science.gov (United States)

    Iwamoto, T.; Takagawa, T.

    2017-12-01

    A long period damped oscillation, or seiche, sometimes happens inside a harbor after passing typhoon. For some cases, a maximum sea level is observed due to the superposition of astronomical tide and seiche rather than a peak of storm surge. Hence to clarify seiche factors for reducing disaster potential is important, a long-period seiche with a fundamental period of 5.46 hours in Tokyo Bay (Konishi, 2008) was investigated through numerical simulations and analyses. We examined the case of Typhoon Phanphon and Vongfong in 2014 (Hereafter Case P and V). The intensity and moving velocity were similar and the best-tracks were an arc-shaped, typical one approaching to Tokyo Bay. The track of Case V was about 1.5 degree higher latitude than that of Case P, only Typhoon Phanphon caused significant seiche.Firstly, numerical simulations for the 2 storm surges at Tokyo Bay were conducted by Regional Ocean Modeling System (ROMS) and Meso-Scale Model Grid Point Values (MSM-GPV). MSM-GPV gave the 10m wind speed and Sea Level Pressure (SLP), especially the Mean Error (ME) and Root Mean Squire Error (RMSE) of SLP were low compared to the 12 JMA observation points data (Case P: ME -0.303hPa, RMSE 1.87hPa, Case V: ME -0.285hPa, RMSE 0.74hPa). The computational results showed that the maximum of storm surge was underestimated but the difference was less than 20cm at 5 observation points in Tokyo Bay(Fig.1, 2).Then, power spectrals, coherences and phase differences of storm surges at the 5 observation points were obtained by spectral analysis of observed and simulated waveforms. For Case P, the phase-difference between the bay mouth and innermost part of Tokyo Bay was little, and coherence was almost 1(Fig.3, 4). However, for Case V, coherence was small around the fundamental period of 5.46 hours. Furthermore, Empirical Orthogonal Function (EOF) analysis of storm surge, SLP and sea surface stress were conducted. The contributions of EOF1 were above 90% for the all variables, the

  1. Root hair mutants of barley

    International Nuclear Information System (INIS)

    Engvild, K.C.; Rasmussen, K.

    2005-01-01

    Barley mutants without root hairs or with short or reduced root hairs were isolated among M 2 seeds of 'Lux' barley (Hordeum vulgare L.) after acidified sodium azide mutagenesis. Root hair mutants are investigated intensively in Arabidopsis where about 40 genes are known. A few root hair mutants are known in maize, rice, barley and tomato. Many plants without root hairs grow quite well with good plant nutrition, and mutants have been used for investigations of uptake of strongly bound nutrients like phosphorus, iron, zinc and silicon. Seed of 'Lux' barley (Sejet Plant Breeding, Denmark) were soaked overnight, and then treated with 1.5-millimolarsodium azide in 0.1 molar sodium phosphate buffer, pH 3, for 2.5 hours according to the IAEA Manual on Mutation Breeding (2nd Ed.). After rinsing in tap water and air-drying, the M 2 seeds were sown in the field the same day. Spikes, 4-6 per M 1 plant, were harvested. The mutation frequency was similar to that obtained with other barley cultivars from which low-phytate mutants were isolated [5]. Seeds were germinated on black filter paper in tap water for 3 or 4 days before scoring for root hair mutants

  2. PGC-1 silencing compounds the perturbation of mitochondrial function caused by mutant SOD1 in skeletal muscle of ALS mouse model

    Directory of Open Access Journals (Sweden)

    Yan eQi

    2015-10-01

    Full Text Available Amyotrophic lateral sclerosis (ALS is a lethal neurodegenerative disease causing death of motor neurons. This study investigated the roles of energy metabolism in the pathogenesis of ALS in the SOD1(G93A transgenic mouse model. Control and SOD1(G93A mice were administered with shcontrol or shPGC-1α in combination with PBS or TZD for 8 weeks. Gene expression was analyzed by quantitative real-time PCR and western blot. ROS and fibrosis were assessed with a colorimetric kit and Sirius staining respectively. Inflammatory cytokines were measured using ELISA kits. The levels of tissue ROS and serum inflammatory cytokines were significantly higher in SOD1(G93A mice compared to control mice, and knocking down PGC-1α drastically increased cytokine levels in both control and SOD1(G93A mice. Muscle fibrosis was much severer in SOD1(G93A mice, and worsened by silencing PGC-1α and attenuate d by TZD. The expression levels of PGC-1α, SOD1, UCP2, and cytochrome C were substantially reduced by shPGC-1α and increased by TZD in muscle of both control and SOD1(G93A mice whereas the level of NF-B was significantly elevated in SOD1(G93A mice, which was further increased by PGC-1α silencing. These data indicated that disruption of energy homeostasis would exacerbate the pathological changes caused by SOD1 mutations to promote the pathogenesis of ALS.

  3. Polymorphic human (CTAT)n microsatellite provides a conserved linkage marker for mouse mutants causing cleft palate, vestibular defects, obesity and ataxia

    Energy Technology Data Exchange (ETDEWEB)

    Griffith, A.J.; Burgess, D.L.; Kohrman, D. [Univ. of MIchigan, Ann Arbor, MI (United States)] [and others

    1994-09-01

    The Twirler mutation (Tw) causing cleft palate {plus_minus} cleft lip, vestibular defects and obesity is located within 0.5 cM of an ataxia locus (ax) on mouse chromosome 18. We identified a transgene-induced insertional mutation with vestibular and craniofacial defects that appears to be a new allele of Twirler. Mouse DNA flanking the transgene insertion site was isolated from a cosmid library. An evolutionarily conserved, zoo blot positive cosmid subclone was used to probe a human {lambda} genomic library. From the sequence of a highly homologous human {lambda} clone, we designed STS primers and screened a human P1 library. DNA from two positive P1 clones was hybridized with simple sequence probes, and a (CTAT){sub 12} repeat was detected. Analysis of 62 CEPH parents with primers flanking the repeat identified six alleles containing 9 to 14 copies of the repeat, at frequencies of 0.17, 0.17, 0.17, 0.27, 0.15 and 0.07, respectively. The observed heterozygosity was 49/62 with a calculated PIC value of 0.76. This polymorphic microsatellite marker, designated Umi3, was mapped to the predicted conserved human linkage group by analysis of somatic cell hybrid panels. The anticipated short distance between Umi3 and the disease genes will facilitate detection of linkage in small families. We would like to type appropriate human pedigrees with Umi3 in order to identify patients with inherited disorders homologous to the mouse mutations Twirler and ataxia.

  4. Defective glycinergic synaptic transmission in zebrafish motility mutants

    Directory of Open Access Journals (Sweden)

    Hiromi Hirata

    2010-01-01

    Full Text Available Glycine is a major inhibitory neurotransmitter in the spinal cord and brainstem. Recently, in vivo analysis of glycinergic synaptic transmission has been pursued in zebrafish using molecular genetics. An ENU mutagenesis screen identified two behavioral mutants that are defective in glycinergic synaptic transmission. Zebrafish bandoneon (beo mutants have a defect in glrbb, one of the duplicated glycine receptor (GlyR β subunit genes. These mutants exhibit a loss of glycinergic synaptic transmission due to a lack of synaptic aggregation of GlyRs. Due to the consequent loss of reciprocal inhibition of motor circuits between the two sides of the spinal cord, motor neurons activate simultaneously on both sides resulting in bilateral contraction of axial muscles of beo mutants, eliciting the so-called ‘accordion’ phenotype. Similar defects in GlyR subunit genes have been observed in several mammals and are the basis for human hyperekplexia/startle disease. By contrast, zebrafish shocked (sho mutants have a defect in slc6a9, encoding GlyT1, a glycine transporter that is expressed by astroglial cells surrounding the glycinergic synapse in the hindbrain and spinal cord. GlyT1 mediates rapid uptake of glycine from the synaptic cleft, terminating synaptic transmission. In zebrafish sho mutants, there appears to be elevated extracellular glycine resulting in persistent inhibition of postsynaptic neurons and subsequent reduced motility, causing the ‘twitch once’ phenotype. We review current knowledge regarding zebrafish ‘accordion’ and ‘twitch once’ mutants, including beo and sho, and report the identification of a new α2 subunit that revises the phylogeny of zebrafish GlyRs.

  5. Defective Glycinergic Synaptic Transmission in Zebrafish Motility Mutants

    Science.gov (United States)

    Hirata, Hiromi; Carta, Eloisa; Yamanaka, Iori; Harvey, Robert J.; Kuwada, John Y.

    2009-01-01

    Glycine is a major inhibitory neurotransmitter in the spinal cord and brainstem. Recently, in vivo analysis of glycinergic synaptic transmission has been pursued in zebrafish using molecular genetics. An ENU mutagenesis screen identified two behavioral mutants that are defective in glycinergic synaptic transmission. Zebrafish bandoneon (beo) mutants have a defect in glrbb, one of the duplicated glycine receptor (GlyR) β subunit genes. These mutants exhibit a loss of glycinergic synaptic transmission due to a lack of synaptic aggregation of GlyRs. Due to the consequent loss of reciprocal inhibition of motor circuits between the two sides of the spinal cord, motor neurons activate simultaneously on both sides resulting in bilateral contraction of axial muscles of beo mutants, eliciting the so-called ‘accordion’ phenotype. Similar defects in GlyR subunit genes have been observed in several mammals and are the basis for human hyperekplexia/startle disease. By contrast, zebrafish shocked (sho) mutants have a defect in slc6a9, encoding GlyT1, a glycine transporter that is expressed by astroglial cells surrounding the glycinergic synapse in the hindbrain and spinal cord. GlyT1 mediates rapid uptake of glycine from the synaptic cleft, terminating synaptic transmission. In zebrafish sho mutants, there appears to be elevated extracellular glycine resulting in persistent inhibition of postsynaptic neurons and subsequent reduced motility, causing the ‘twitch-once’ phenotype. We review current knowledge regarding zebrafish ‘accordion’ and ‘twitch-once’ mutants, including beo and sho, and report the identification of a new α2 subunit that revises the phylogeny of zebrafish GlyRs. PMID:20161699

  6. Biochemical Analysis of Two Single Mutants that Give Rise to a Polymorphic G6PD A-Double Mutant

    Directory of Open Access Journals (Sweden)

    Edson Jiovany Ramírez-Nava

    2017-10-01

    Full Text Available Glucose-6-phosphate dehydrogenase (G6PD is a key regulatory enzyme that plays a crucial role in the regulation of cellular energy and redox balance. Mutations in the gene encoding G6PD cause the most common enzymopathy that drives hereditary nonspherocytic hemolytic anemia. To gain insights into the effects of mutations in G6PD enzyme efficiency, we have investigated the biochemical, kinetic, and structural changes of three clinical G6PD variants, the single mutations G6PD A+ (Asn126AspD and G6PD Nefza (Leu323Pro, and the double mutant G6PD A− (Asn126Asp + Leu323Pro. The mutants showed lower residual activity (≤50% of WT G6PD and displayed important kinetic changes. Although all Class III mutants were located in different regions of the three-dimensional structure of the enzyme and were not close to the active site, these mutants had a deleterious effect over catalytic activity and structural stability. The results indicated that the G6PD Nefza mutation was mainly responsible for the functional and structural alterations observed in the double mutant G6PD A−. Moreover, our study suggests that the G6PD Nefza and G6PD A− mutations affect enzyme functions in a similar fashion to those reported for Class I mutations.

  7. MWCNTs of different physicochemical properties cause similar inflammatory responses, but differences in transcriptional and histological markers of fibrosis in mouse lungs

    International Nuclear Information System (INIS)

    Poulsen, Sarah S.; Saber, Anne T.; Williams, Andrew; Andersen, Ole; Købler, Carsten; Atluri, Rambabu; Pozzebon, Maria E.; Mucelli, Stefano P.; Simion, Monica; Rickerby, David; Mortensen, Alicja; Jackson, Petra; Kyjovska, Zdenka O.

    2015-01-01

    Multi-walled carbon nanotubes (MWCNTs) are an inhomogeneous group of nanomaterials that vary in lengths, shapes and types of metal contamination, which makes hazard evaluation difficult. Here we present a toxicogenomic analysis of female C57BL/6 mouse lungs following a single intratracheal instillation of 0, 18, 54 or 162 μg/mouse of a small, curled (CNT Small , 0.8 ± 0.1 μm in length) or large, thick MWCNT (CNT Large , 4 ± 0.4 μm in length). The two MWCNTs were extensively characterized by SEM and TEM imaging, thermogravimetric analysis, and Brunauer–Emmett–Teller surface area analysis. Lung tissues were harvested 24 h, 3 days and 28 days post-exposure. DNA microarrays were used to analyze gene expression, in parallel with analysis of bronchoalveolar lavage fluid, lung histology, DNA damage (comet assay) and the presence of reactive oxygen species (dichlorodihydrofluorescein assay), to profile and characterize related pulmonary endpoints. Overall changes in global transcription following exposure to CNT Small or CNT Large were similar. Both MWCNTs elicited strong acute phase and inflammatory responses that peaked at day 3, persisted up to 28 days, and were characterized by increased cellular influx in bronchoalveolar lavage fluid, interstitial pneumonia and gene expression changes. However, CNT Large elicited an earlier onset of inflammation and DNA damage, and induced more fibrosis and a unique fibrotic gene expression signature at day 28, compared to CNT Small . The results indicate that the extent of change at the molecular level during early response phases following an acute exposure is greater in mice exposed to CNT Large , which may eventually lead to the different responses observed at day 28. - Highlights: • We evaluate the toxicogenomic response in mice following MWCNT instillation. • Two MWCNTs of different properties were examined and thoroughly characterized. • MWCNT exposure leads to increased pulmonary inflammation and acute phase

  8. MWCNTs of different physicochemical properties cause similar inflammatory responses, but differences in transcriptional and histological markers of fibrosis in mouse lungs

    Energy Technology Data Exchange (ETDEWEB)

    Poulsen, Sarah S., E-mail: spo@nrcwe.dk [National Research Centre for the Working Environment, Copenhagen DK-2100 (Denmark); Department of Science, Systems and Models, Roskilde University, DK-4000 Roskilde (Denmark); Saber, Anne T., E-mail: ats@nrcwe.dk [National Research Centre for the Working Environment, Copenhagen DK-2100 (Denmark); Williams, Andrew, E-mail: Andrew.williams@hc-sc.gc.ca [Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario K1A 0K9 (Canada); Andersen, Ole, E-mail: oa@ruc.dk [Department of Science, Systems and Models, Roskilde University, DK-4000 Roskilde (Denmark); Købler, Carsten, E-mail: carko@nanotech.dtu.dk [Department of Micro- and Nanotechnology, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Atluri, Rambabu, E-mail: rba@nrcwe.dk [Nanologica AB, SE-114 28 Stockholm (Sweden); Pozzebon, Maria E., E-mail: mariaelena.pozzebon@yahoo.it [Veneto Nanotech SCpA, ECSIN — European Centre for the Sustainable Impact of Nanotechnology, I-45100 Rovigo (Italy); Mucelli, Stefano P., E-mail: stefano.pozzimucelli@venetonanotech.it [Veneto Nanotech SCpA, ECSIN — European Centre for the Sustainable Impact of Nanotechnology, I-45100 Rovigo (Italy); Simion, Monica, E-mail: moni304ro@gmail.com [Laboratory of Nanobiotechnology, National Institute for Research and Development in Microtechnologies, 077190 Bucharest (Romania); Rickerby, David, E-mail: david.rickerby@jrc.ec.europa.eu [European Commission Joint Research Centre Institute for Environment and Sustainability, I-21027 Ispra, VA (Italy); Mortensen, Alicja, E-mail: almo@food.dtu.dk [National Food Institute, Technical University of Denmark, Søborg (Denmark); Jackson, Petra, E-mail: pja@nrcwe.dk [National Research Centre for the Working Environment, Copenhagen DK-2100 (Denmark); Kyjovska, Zdenka O., E-mail: zky@nrcwe.dk [National Research Centre for the Working Environment, Copenhagen DK-2100 (Denmark); and others

    2015-04-01

    Multi-walled carbon nanotubes (MWCNTs) are an inhomogeneous group of nanomaterials that vary in lengths, shapes and types of metal contamination, which makes hazard evaluation difficult. Here we present a toxicogenomic analysis of female C57BL/6 mouse lungs following a single intratracheal instillation of 0, 18, 54 or 162 μg/mouse of a small, curled (CNT{sub Small}, 0.8 ± 0.1 μm in length) or large, thick MWCNT (CNT{sub Large}, 4 ± 0.4 μm in length). The two MWCNTs were extensively characterized by SEM and TEM imaging, thermogravimetric analysis, and Brunauer–Emmett–Teller surface area analysis. Lung tissues were harvested 24 h, 3 days and 28 days post-exposure. DNA microarrays were used to analyze gene expression, in parallel with analysis of bronchoalveolar lavage fluid, lung histology, DNA damage (comet assay) and the presence of reactive oxygen species (dichlorodihydrofluorescein assay), to profile and characterize related pulmonary endpoints. Overall changes in global transcription following exposure to CNT{sub Small} or CNT{sub Large} were similar. Both MWCNTs elicited strong acute phase and inflammatory responses that peaked at day 3, persisted up to 28 days, and were characterized by increased cellular influx in bronchoalveolar lavage fluid, interstitial pneumonia and gene expression changes. However, CNT{sub Large} elicited an earlier onset of inflammation and DNA damage, and induced more fibrosis and a unique fibrotic gene expression signature at day 28, compared to CNT{sub Small}. The results indicate that the extent of change at the molecular level during early response phases following an acute exposure is greater in mice exposed to CNT{sub Large}, which may eventually lead to the different responses observed at day 28. - Highlights: • We evaluate the toxicogenomic response in mice following MWCNT instillation. • Two MWCNTs of different properties were examined and thoroughly characterized. • MWCNT exposure leads to increased pulmonary

  9. The adaptability of upland rice waxy mutant (Oryza sativa L.) to marginal land in Batumarta

    International Nuclear Information System (INIS)

    Dwimahyani, Ita; Mitrosuhardjo, M.M.

    1998-01-01

    A field experiment had been conducted at Batumarta, Lampung Province to test the adaptability of upland rice waxy mutant (DT 20.11.84) at marginal land. Similar experiments had also been conducted in fertilize soil at Ps. Jumat, Jakarta and Citayam, Kabupaten Bogor. Agronomic evaluation such as number of tiller, panicle length number of seeds per tiller, and weight of 1000 grains from waxy mutant line, which were cultivated at Batumarta showed adaptability was better than the original variety (Danau Tempe). Grains yield of waxy mutant line per ha at marginal land (Batubara) was higher than Danau Tempe i.e 2,34 and 1,89 ton/ha respectively. In addition to grain yield of waxy mutant line at Psr Jumat, Jakarta and Citayam, Bogor was lower than Danau Tempe. The Low of grain yield that waxy mutant compared with the original variety line was caused by number of tiller and panicle length of waxy mutant line also low. Results of experiment can be concluded that waxy mutant line was favourable growing at marginal land when compared with the original variety. (author)

  10. Gamma-radiation Mutagenesis in Genetically Unstable Barley Mutants. Pt. 2. Comparison of Various Mutants

    International Nuclear Information System (INIS)

    Balchiuniene, L.

    1995-01-01

    Spontaneous and gamma-induced mutability was compared in two groups of genetically unstable barley ear structure mutants - tweaky spike (tw) and branched ear (be). Instability in different loci causes different levels of spontaneous and gamma-induced mutability. A high spontaneous level of chlorophyll mutations is peculiar to be-ust mutants. It is suggested that the high level of induced chlorophyll mutations in allelic tw mutants is a result of better surviving of chlorophyll mutation carriers in the genotypical-physiological environment created by mutant tw alleles. (author). 6 refs., 2 tabs

  11. Heterozygosity for an in-frame deletion causes glutaryl-CoA dehydrogenase deficiency in a patient detected by newborn screening: investigation of the effect of the mutant allele

    DEFF Research Database (Denmark)

    Bross, Peter; Frederiksen, Jane B; Bie, Anne S

    2012-01-01

    the proband were consistent with a mild biochemical GA-1 phenotype. Recombinant expression of the mutant variant in E. coli showed that the GCDH-(p.Gly185_Ser190del) protein displayed severely decreased assembly into tetramers and enzyme activity. To discover a potential dominant negative effect of the mutant...... with the hypothesis that heterozygosity for this mutation confers a dominant negative effect resulting in a GCDH enzyme activity that is significantly lower than the expected 50%....

  12. Disturbed secretion of mutant adiponectin associated with the metabolic syndrome.

    Science.gov (United States)

    Kishida, Ken; Nagaretani, Hiroyuki; Kondo, Hidehiko; Kobayashi, Hideki; Tanaka, Sachiyo; Maeda, Norikazu; Nagasawa, Azumi; Hibuse, Toshiyuki; Ohashi, Koji; Kumada, Masahiro; Nishizawa, Hitoshi; Okamoto, Yoshihisa; Ouchi, Noriyuki; Maeda, Kazuhisa; Kihara, Shinji; Funahashi, Tohru; Matsuzawa, Yuji

    2003-06-20

    Adiponectin, an adipocyte-derived protein, consists of collagen-like fibrous and complement C1q-like globular domains, and circulates in human plasma in a multimeric form. The protein exhibits anti-diabetic and anti-atherogenic activities. However, adiponectin plasma concentrations are low in obese subjects, and hypoadiponectinemia is associated with the metabolic syndrome, which is a cluster of insulin resistance, type 2 diabetes mellitus, hypertension, and dyslipidemia. We have recently reported a missense mutation in the adiponectin gene, in which isoleucine at position 164 in the globular domain is substituted with threonine (I164T). Subjects with this mutation showed markedly low level of plasma adiponectin and clinical features of the metabolic syndrome. Here, we examined the molecular characteristics of the mutant protein associated with a genetic cause of hypoadiponectinemia. The current study revealed (1) the mutant protein showed an oligomerization state similar to the wild-type as determined by gel filtration chromatography and, (2) the mutant protein exhibited normal insulin-sensitizing activity, but (3) pulse-chase study showed abnormal secretion of the mutant protein from adipose tissues. Our results suggest that I164T mutation is associated with hypoadiponectinemia through disturbed secretion into plasma, which may contribute to the development of the metabolic syndrome.

  13. Genetic fingerprinting of mutant rose cultivars

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S; Prasad, K V; Singh, K P; Singh, A.P. [Division of Floriculture and Landscaping, Indian Agricultural Research Institute, Pusa, New Delhi (India)], E-mail: kvprasad66@gmail.com

    2008-07-01

    Six rose mutants evolved at the Indian Agricultural Research Institute, New Delhi from four parent cultivars were characterized based on RAPD markers. Contrary to the earlier findings our effort has conclusively proven that the RAPD markers are indeed robust tools to discern the mutants from their parents. Among 40 primers screened, 7 primers produced inconsistent banding pattern. The number of polymorphic bands varied between 4 (OPA 14) and 10 (OPA1) with an average of 6.5 bands per primer. The percentage polymorphism ranged from 62.5 (OPM 9) to 100 percent (OPA 1). Most of the primers produced monomorphic bands between parent and mutant rose cultivars. When primer OPA 2 was used a specific band of 2.5 kb was noticed in mutant cv. Pusa Urmil and cv. Pusa Abhishek but was absent in parent cv. Jantar Mantar. A polymorphic band of 750 bp was noticed in the parent Kiss of Fire and helped in differentiating the parent from its mutant when amplified with OPK 3. Primer OPS 16 produced discriminatory band of 800 bp in mutant cv. Pink Sport of Montezuma while it was absent in its parent cv. Montezuma. Another specific band of 650 bp was present in parent cv. Montezuma and absent in its mutant cv. Pink Sport of Montezuma signifying the uniqueness of the mutant. Primer OPM 5 brought out distinct polymorphism among the parent Jantar Mantar and its three mutants with absence of a specific band of 1.5 kb in the parent. The four parents and 6 mutants were divided into four distinct groups in the Dendogram constructed by UPGMA method. The most genetically similar cultivar among the 10 cultivars analyzed are Montezuma and its pink sport of Montezuma whereas Abhisarika a mutant of cv. Kiss of Fire was distinctly different and formed a separate cluster. (author)

  14. Promising rice mutants

    International Nuclear Information System (INIS)

    Hakim, L.; Azam, M.A.; Miah, A.J.; Mansur, M.A.; Akanda, H.R.

    1988-01-01

    Two induced mutants namely, Mut NS 1 (tall) and Mut NS 5 (semi-dwarf) derived from rice variety Nizersail were evaluated for various agronomic characters at four locations in Bangladesh. Both the mutants matured about three weeks earlier and yielded significantly higher than the parent variety Nizersail. (author). 3 tabs., 9 refs

  15. Mutant heterosis in rice

    International Nuclear Information System (INIS)

    1987-01-01

    In the variety TKM6 a high yielding semidwarf mutant has been induced. This TKM6 mutant was used in test crosses with a number of other varieties and mutants to examine the extent of heterosis of dwarfs in rice and to select superior crosses. An excerpt of the published data is given. It appears from the backcross of the mutant with its original variety, that an increase in number of productive tillers occurs in the hybrid, leading to a striking grain yield increase, while the semi-dwarf culm length (the main mutant character) reverts to the normal phenotype. In the cross with IR8 on the other hand, there is only a minimal increase in tiller number but a substantial increase in TGW leading to more than 30% yield increase over the better parent

  16. Mutation in cpsf6/CFIm68 (Cleavage and Polyadenylation Specificity Factor Subunit 6 causes short 3'UTRs and disturbs gene expression in developing embryos, as revealed by an analysis of primordial germ cell migration using the medaka mutant naruto.

    Directory of Open Access Journals (Sweden)

    Takao Sasado

    Full Text Available Our previous studies analyzing medaka mutants defective in primordial germ cell (PGC migration identified cxcr4b and cxcr7, which are both receptors of the chemokine sdf1/cxcl12, as key regulators of PGC migration. Among PGC migration mutants, naruto (nar is unique in that the mutant phenotype includes gross morphological abnormalities of embryos, suggesting that the mutation affects a broader range of processes. A fine genetic linkage mapping and genome sequencing showed the nar gene encodes Cleavage and Polyadenylation Specificity Factor subunit 6 (CPSF6/CFIm68. CPSF6 is a component of the Cleavage Factor Im complex (CFIm which plays a key role in pre-mRNA 3'-cleavage and polyadenylation. 3'RACE of sdf1a/b and cxcr7 transcripts in the mutant embryos indicated shorter 3'UTRs with poly A additions occurring at more upstream positions than wild-type embryos, suggesting CPSF6 functions to prevent premature 3'UTR cleavage. In addition, expression of the coding region sequences of sdf1a/b in nar mutants was more anteriorly extended in somites than wild-type embryos, accounting for the abnormally extended distribution of PGCs in nar mutants. An expected consequence of shortening 3'UTR is the escape from the degradation mechanism mediated by microRNAs interacting with distal 3'UTR sequence. The abnormal expression pattern of sdf1a coding sequence may be at least partially accounted for by this mechanism. Given the pleiotropic effects of nar mutation, further analysis using the nar mutant will reveal processes in which CPSF6 plays essential regulatory roles in poly A site selection and involvement of 3'UTRs in posttranscriptional gene regulation in various genes in vivo.

  17. Mutation in cpsf6/CFIm68 (Cleavage and Polyadenylation Specificity Factor Subunit 6) causes short 3'UTRs and disturbs gene expression in developing embryos, as revealed by an analysis of primordial germ cell migration using the medaka mutant naruto.

    Science.gov (United States)

    Sasado, Takao; Kondoh, Hisato; Furutani-Seiki, Makoto; Naruse, Kiyoshi

    2017-01-01

    Our previous studies analyzing medaka mutants defective in primordial germ cell (PGC) migration identified cxcr4b and cxcr7, which are both receptors of the chemokine sdf1/cxcl12, as key regulators of PGC migration. Among PGC migration mutants, naruto (nar) is unique in that the mutant phenotype includes gross morphological abnormalities of embryos, suggesting that the mutation affects a broader range of processes. A fine genetic linkage mapping and genome sequencing showed the nar gene encodes Cleavage and Polyadenylation Specificity Factor subunit 6 (CPSF6/CFIm68). CPSF6 is a component of the Cleavage Factor Im complex (CFIm) which plays a key role in pre-mRNA 3'-cleavage and polyadenylation. 3'RACE of sdf1a/b and cxcr7 transcripts in the mutant embryos indicated shorter 3'UTRs with poly A additions occurring at more upstream positions than wild-type embryos, suggesting CPSF6 functions to prevent premature 3'UTR cleavage. In addition, expression of the coding region sequences of sdf1a/b in nar mutants was more anteriorly extended in somites than wild-type embryos, accounting for the abnormally extended distribution of PGCs in nar mutants. An expected consequence of shortening 3'UTR is the escape from the degradation mechanism mediated by microRNAs interacting with distal 3'UTR sequence. The abnormal expression pattern of sdf1a coding sequence may be at least partially accounted for by this mechanism. Given the pleiotropic effects of nar mutation, further analysis using the nar mutant will reveal processes in which CPSF6 plays essential regulatory roles in poly A site selection and involvement of 3'UTRs in posttranscriptional gene regulation in various genes in vivo.

  18. Combinations of mutant FAD2 and FAD3 genes to produce high oleic acid and low linolenic acid soybean oil.

    Science.gov (United States)

    Pham, Anh-Tung; Shannon, J Grover; Bilyeu, Kristin D

    2012-08-01

    High oleic acid soybeans were produced by combining mutant FAD2-1A and FAD2-1B genes. Despite having a high oleic acid content, the linolenic acid content of these soybeans was in the range of 4-6 %, which may be high enough to cause oxidative instability of the oil. Therefore, a study was conducted to incorporate one or two mutant FAD3 genes into the high oleic acid background to further reduce the linolenic acid content. As a result, soybean lines with high oleic acid and low linolenic acid (HOLL) content were produced using different sources of mutant FAD2-1A genes. While oleic acid content of these HOLL lines was stable across two testing environments, the reduction of linolenic acid content varied depending on the number of mutant FAD3 genes combined with mutant FAD2-1 genes, on the severity of mutation in the FAD2-1A gene, and on the testing environment. Combination of two mutant FAD2-1 genes and one mutant FAD3 gene resulted in less than 2 % linolenic acid content in Portageville, Missouri (MO) while four mutant genes were needed to achieve the same linolenic acid in Columbia, MO. This study generated non-transgenic soybeans with the highest oleic acid content and lowest linolenic acid content reported to date, offering a unique alternative to produce a fatty acid profile similar to olive oil.

  19. The pht4;1-3 mutant line contains a loss of function allele in the Fatty Acid Desaturase 7 gene caused by a remnant inactivated selection marker-a cautionary tale.

    Science.gov (United States)

    Nilsson, Anders K; Andersson, Mats X

    2017-01-01

    A striking and unexpected biochemical phenotype was found in an insertion mutant line in the model plant Arabidopsis thaliana . One of two investigated insertion mutant lines in the gene encoding the phosphate transporter PHT4;1 demonstrated a prominent loss of trienoic fatty acids, whereas the other insertion line was indistinguishable from wild type in this aspect. We demonstrate that the loss of trienoic fatty acids was due to a remnant inactive negative selection marker gene in this particular transposon tagged line, pht4;1-3 . This constitutes a cautionary tale that warns of the importance to confirm the loss of this type of selection markers and the importance of verifying the relationship between a phenotype and genotype by more than one independent mutant line or alternatively genetic complementation.

  20. Inactivation of JAK2/STAT3 Signaling Axis and Downregulation of M1 mAChR Cause Cognitive Impairment in klotho Mutant Mice, a Genetic Model of Aging

    Science.gov (United States)

    Park, Seok-Joo; Shin, Eun-Joo; Min, Sun Seek; An, Jihua; Li, Zhengyi; Hee Chung, Yoon; Hoon Jeong, Ji; Bach, Jae-Hyung; Nah, Seung-Yeol; Kim, Won-Ki; Jang, Choon-Gon; Kim, Yong-Sun; Nabeshima, Yo-ichi; Nabeshima, Toshitaka; Kim, Hyoung-Chun

    2013-01-01

    We previously reported cognitive dysfunction in klotho mutant mice. In the present study, we further examined novel mechanisms involved in cognitive impairment in these mice. Significantly decreased janus kinase 2 (JAK2) and signal transducer and activator of transcription3 (STAT3) phosphorylation were observed in the hippocampus of klotho mutant mice. A selective decrease in protein expression and binding density of the M1 muscarinic cholinergic receptor (M1 mAChR) was observed in these mice. Cholinergic parameters (ie, acetylcholine (ACh), choline acetyltransferase (ChAT), and acetylcholinesterase (AChE)) and NMDAR-dependent long-term potentiation (LTP) were significantly impaired in klotho mutant mice. McN-A-343 (McN), an M1 mAChR agonist, significantly attenuated these impairments. AG490 (AG), a JAK2 inhibitor, counteracted the attenuating effects of McN, although AG did not significantly alter the McN-induced effect on AChE. Furthermore, AG significantly inhibited the attenuating effects of McN on decreased NMDAR-dependent LTP, protein kinase C βII, p-ERK, p-CREB, BDNF, and p-JAK2/p-STAT3-expression in klotho mutant mice. In addition, k252a, a BDNF receptor tyrosine kinase B (TrkB) inhibitor, significantly counteracted McN effects on decreased ChAT, ACh, and M1 mAChR and p-JAK2/p-STAT3 expression. McN-induced effects on cognitive impairment in klotho mutant mice were consistently counteracted by either AG or k252a. Our results suggest that inactivation of the JAK2/STAT3 signaling axis and M1 mAChR downregulation play a critical role in cognitive impairment observed in klotho mutant mice. PMID:23389690

  1. Phenotypic and epistatic grouping of hypo- and hyper-rec mus mutants in Aspergillus.

    Science.gov (United States)

    Kafer, E; Chae, S K

    1994-03-01

    The mutants musK to musS of Aspergillus nidulans are sensitive to methyl-methanesulfonate (MMS) and several of them are meiotic-defective and alter mitotic recombination frequencies. All were found to be cross-sensitive to 4-nitro-quinoline-N-oxide (4-NQO) but unexpectedly none of them was hypersensitive to gamma-rays and few to UV light. Double mus; uvs mutants were constructed to test for interactions with uvs mutations of the four epistatic groups of Aspergillus, "UvsF", "UvsC", "UvsI", and "UvsB". All meiotic-defective mus mutations caused some lethal interactions, usually with uvsF. None of them showed epistasis with UvsF or UvsB group mutants and one, musO, may represent a new group. Three mus mutations that affect recombination were assigned to the UvsC group, namely musN and K, and also musL which is recombination-defective and closely resembles uvsC. While uvsC mutants are mutators and lack UV-mutagenesis, most mus mutants had no effects on mutation. Only musR, which appeared epistatic with uvsI, showed reduced UV-reversion frequencies similar to uvsI. The recombination-proficient mus mutants appeared to be epistatic with more than one group, but in several cases sensitivities were slight and overlaps insufficient to obtain corroborating results with MMS and 4-NQO.

  2. Mutant genes in pea breeding

    International Nuclear Information System (INIS)

    Swiecicki, W.K.

    1990-01-01

    Full text: Mutations of genes Dpo (dehiscing pods) and A (anthocyanin synthesis) played a role in pea domestication. A number of other genes were important in cultivar development for 3 types of usage (dry seeds, green vegetable types, fodder), e.g. fn, fna, le, p, v, fas and af. New genes (induced and spontaneous), are important for present ideotypes and are registered by the Pisum Genetics Association (PGA). Comparison of a pea variety ideotype with the variation available in gene banks shows that breeders need 'new' features. In mutation induction experiments, genotype, mutagen and method of treatment (e.g. combined or fractionated doses) are varied for broadening the mutation spectrum and selecting more genes of agronomic value. New genes are genetically analysed. In Poland, some mutant varieties with the gene afila were registered, controlling lodging by a shorter stem and a higher number of internodes. Really non-lodging pea varieties could strongly increase seed yield. But the probability of detecting a major gene for lodging resistance is low. Therefore, mutant genes with smaller influence on plant architecture are sought, to combine their effect by crossing. Promising seem to be the genes rogue, reductus and arthritic as well as a number of mutant genes not yet genetically identified. The gene det for terminal inflorescence - similarly to Vicia faba - changes plant development. Utilisation of assimilates and ripening should be better. Improvement of harvest index should give higher seed yield. A number of genes controlling disease resistance are well known (eg. Fw, Fnw, En, mo and sbm). Important in mass screening of resistance are closely linked gene markers. Pea gene banks collect respective lines, but mutants induced in highly productive cultivars would be better. Inducing gene markers sometimes seems to be easier than transfer by crossing. Mutation induction in pea breeding is probably more important because a high number of monogenic features are

  3. Evaluation of vaccine candidate potential of deltaaroA, deltahtrA and deltaaroAdeltahtrA mutants of Salmonella enterica subspecies enterica serovar Abortusequi in guinea pigs.

    Science.gov (United States)

    Singh, Bhoj Raj; Chandra, Mudit; Hansda, Dhananjoy; Alam, Javed; Babu, Narayanan; Siddiqui, Mehtab Z; Agrawal, Ravi K; Sharma, Gautam

    2013-04-01

    Salmonella enterica subspecies enterica serovar Abortusequi (S. Abortusequi), a host adapted Salmonella causes abortions, still births and foal mortality in equids. Though known since more than 100 years, it is still a problem in many of the developing countries including India. There is dearth of really good vaccine affording immunity lasting at least for one full gestation. In search of a potential vaccine candidate, three defined deletion mutants (deltaaroA, deltahtrA and deltaaroAdeltahtrA) of S. Abortusequi were tested in guinea pig model for attenuation, safety, immunogenicity, humoral immune response, protective efficacy and persistence in host. The deltahtrA and deltaaroAdeltahtrA mutants were found to be safe on oral inoculation in doses as high as 4.2 x 10(9) cfu/animal. Also through subcutaneous inoculation deltaaroAdeltahtrA mutant did not induce any abortion in pregnant guinea pigs. All the three mutants did not induce any illness or death in 1-2 week-old baby guinea pigs except deltahtrA mutant which caused mortality on intraperitoneal inoculation. Inoculation with mutants protected against challenge and increased breeding efficiency of guinea pigs. After >4.5 months of mutant inoculation, guinea pigs were protected against abortifacient dose of wild type S. Abortusequi and mother guinea pigs also conferred resistance to their babies to the similar challenge. Early humoral immune response of S. Abortusequi mutants was characteristic. Faecal excretion of deltaaroA and htrA mutants was detected up to 45 days of inoculation in guinea pigs while deltaaroAdeltahtrA mutant could not be detected after 21 days of inoculation. The results indicated that the double deletion mutant (deltaaroAdeltahtrA) was the most effective and safe candidate for vaccination against S. Abortusequi through mucosal route of inoculation.

  4. Exogenous Expressions of FTO Wild-Type and R316Q Mutant Proteins Caused an Increase in HNRPK Levels in 3T3-L1 Cells as Demonstrated by DIGE Analysis

    Directory of Open Access Journals (Sweden)

    Nil Guzel

    2017-01-01

    Full Text Available Fat mass and obesity-associated protein is an enzyme that oxidatively demethylates DNA. Although there are numerous studies regarding the catalytic function of FTO, the overall existence or absence of FTO on cellular proteome has not been investigated. This study investigated the changes in the soluble proteome of 3T3-L1 cells upon expression of the WT and the mutant (R316Q FTO proteins. Protein extracts prepared from 3T3-L1 cells expressing either the WT or the mutant FTO proteins were used in DIGE experiments. Analysis of the data revealed the number of spots matched to every member and there were 350 ± 20 spots with 30.5% overall mean coefficient of variation. Eleven regulated protein spots were excised from the gels and identified by MALDI-TOF/TOF. One of the identified proteins was heterogeneous nuclear ribonucleoprotein K, which displayed more than 2.6- and 3.7-fold increases in its abundance in the WT and the mutant FTO expressing cells, respectively. Western blot analysis validated these observations. This is the first study revealing the presence of a parallel increase in expressions of FTO and HNRNPK proteins. This increase may codictate the metabolic changes occurring in the cell and may attribute a significance to HNRNPK in FTO-associated transformations.

  5. Potent inhibition of HIV-1 replication by a Tat mutant.

    Directory of Open Access Journals (Sweden)

    Luke W Meredith

    Full Text Available Herein we describe a mutant of the two-exon HIV-1 Tat protein, termed Nullbasic, that potently inhibits multiple steps of the HIV-1 replication cycle. Nullbasic was created by replacing the entire arginine-rich basic domain of wild type Tat with glycine/alanine residues. Like similarly mutated one-exon Tat mutants, Nullbasic exhibited transdominant negative effects on Tat-dependent transactivation. However, unlike previously reported mutants, we discovered that Nullbasic also strongly suppressed the expression of unspliced and singly-spliced viral mRNA, an activity likely caused by redistribution and thus functional inhibition of HIV-1 Rev. Furthermore, HIV-1 virion particles produced by cells expressing Nullbasic had severely reduced infectivity, a defect attributable to a reduced ability of the virions to undergo reverse transcription. Combination of these inhibitory effects on transactivation, Rev-dependent mRNA transport and reverse transcription meant that permissive cells constitutively expressing Nullbasic were highly resistant to a spreading infection by HIV-1. Nullbasic and its activities thus provide potential insights into the development of potent antiviral therapeutics that target multiple stages of HIV-1 infection.

  6. Productive mutants of niger

    International Nuclear Information System (INIS)

    Misra, R.C.

    2001-01-01

    Seeds of six niger (Guizotia abyssinica Cass.) varieties ('GA-10', 'ONS-8', 'IGP-72', 'N-71', 'NB-9' and 'UN-4') were treated with 0.5, 0.75 and 1% ethyl methanesulphonate. After four generations of selection, 29 mutant lines were developed and those were evaluated from 1990-92 during Kharif (July to October) and Rabi (December to March) seasons. Average plant characteristics and yield data of four high yielding mutants along with 'IGP-76' (National Check), GA-10 (Zonal Check) and 'Semiliguda Local' (Local Check) are presented

  7. Seed protein and nitrogen fixation in chickpea mutant variety Hyprosola

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, H E; Gibson, A H; Oram, R N [CSIRO, Division of Plant Industry, Canberra ACT (Australia); Shaikh, M A.Q. [Bangladesh Institute of Nuclear Agriculture, Mymensingh (Bangladesh)

    1989-01-01

    Full text: 'Hyprosola' is a high yielding, high protein mutant cultivar obtained after gamma irradiation from the variety 'Faridpur-1'. The mutant yields 45 % more protein per unit area. The essential amino acid index is unchanged. It is likely that the high nutritional value in 'Hyprosola' seed protein arises from an increase in the albumin:globulin ratio. Nitrogen fixation rates of the mutant during the first 7 weeks of growth were found to be similar to 'Faridpur-1'. Under field conditions, the mutant may be able to nodulate more rapidly and more extensively than the parent variety. (author)

  8. Susceptibility of glucokinase-MODY mutants to inactivation by oxidative stress in pancreatic β-cells.

    Science.gov (United States)

    Cullen, Kirsty S; Matschinsky, Franz M; Agius, Loranne; Arden, Catherine

    2011-12-01

    The posttranslational regulation of glucokinase (GK) differs in hepatocytes and pancreatic β-cells. We tested the hypothesis that GK mutants that cause maturity-onset diabetes of the young (GK-MODY) show compromised activity and posttranslational regulation in β-cells. Activity and protein expression of GK-MODY and persistent hyperinsulinemic hypoglycemia of infancy (PHHI) mutants were studied in β-cell (MIN6) and non-β-cell (H4IIE) models. Binding of GK to phosphofructo-2-kinase, fructose-2,6-bisphosphatase (PFK2/FBPase2) was studied by bimolecular fluorescence complementation in cell-based models. Nine of 11 GK-MODY mutants that have minimal effect on enzyme kinetics in vitro showed decreased specific activity relative to wild type when expressed in β-cells. A subset of these were stable in non-β-cells but showed increased inactivation in conditions of oxidative stress and partial reversal of inactivation by dithiothreitol. Unlike the GK-MODY mutants, four of five GK-PHHI mutants had similar specific activity to wild type and Y214C had higher activity than wild type. The GK-binding protein PFK2/FBPase2 protected wild-type GK from oxidative inactivation and the decreased stability of GK-MODY mutants correlated with decreased interaction with PFK2/FBPase2. Several GK-MODY mutants show posttranslational defects in β-cells characterized by increased susceptibility to oxidative stress and/or protein instability. Regulation of GK activity through modulation of thiol status may be a physiological regulatory mechanism for the control of GK activity in β-cells.

  9. PNRI mutant variety: Cordyline 'Afable'

    International Nuclear Information System (INIS)

    Aurigue, Fernando B.

    2012-01-01

    Cordyline 'Afable', registered by the Philippine Nuclear Research Institute as NSIC 2009 Or-83, is an induced mutant developed from Cordyline 'Kiwi' by treating stem cuttings with acute gamma radiation from a Cobalt-60 source. The new mutant is identical to Cordyline 'Kiwi' in growth habit but differs in foliage color, and exhibits field resistance to Phytophthora sp., a fungus that causes leaf blight and rot in Ti plants. Results of this mutation breeding experiment showed that leaf color was altered by gamma irradiation and resistance to fungal diseases was improved. It also demonstrated how mutations that occur in nature may be generated artificially. Propagation of cordyline 'Afable' is true-to-type by vegetative propagation methods, such as separation of suckers and offshoots, shoot tip cutting, and top cutting. Aside from landscaping material, terrarium or dish-garden plant, it is ideal as containerized plant for indoor and outdoor use. The leaves or shoots may be harvested as cut foliage for flower arrangements. (author)

  10. Novel CLCNKB mutations causing Bartter syndrome affect channel surface expression.

    Science.gov (United States)

    Keck, Mathilde; Andrini, Olga; Lahuna, Olivier; Burgos, Johanna; Cid, L Pablo; Sepúlveda, Francisco V; L'hoste, Sébastien; Blanchard, Anne; Vargas-Poussou, Rosa; Lourdel, Stéphane; Teulon, Jacques

    2013-09-01

    Mutations in the CLCNKB gene encoding the ClC-Kb Cl(-) channel cause Bartter syndrome, which is a salt-losing renal tubulopathy. Here, we investigate the functional consequences of seven mutations. When expressed in Xenopus laevis oocytes, four mutants carried no current (c.736G>C, p.Gly246Arg; c.1271G>A, p.Gly424Glu; c.1313G>A, p.Arg438His; c.1316T>C, p.Leu439Pro), whereas others displayed a 30%-60% reduction in conductance as compared with wild-type ClC-Kb (c.242T>C, p.Leu81Pro; c.274C>T, p.Arg92Trp; c.1052G>C, p.Arg351Pro). Anion selectivity and sensitivity to external Ca(2+) and H(+), typical of the ClC-Kb channel, were not modified in the partially active mutants. In oocytes, we found that all the mutations reduced surface expression with a profile similar to that observed for currents. In HEK293 cells, the currents in the mutants had similar profiles to those obtained in oocytes, except for p.Leu81Pro, which produced no current. Furthermore, p.Arg92Trp and p.Arg351Pro mutations did not modify the unit-conductance of closely related ClC-K1. Western blot analysis in HEK293 cells showed that ClC-Kb protein abundance was lower for the nonconducting mutants but similar to wild-type for other mutants. Overall, two classes of mutants can be distinguished: nonconducting mutants associated with low total protein expression, and partially conducting mutants with unaltered channel properties and ClC-Kb protein abundance. © 2013 WILEY PERIODICALS, INC.

  11. [Intragenic mitotic recombination induced by ultraviolet and gamma rays in radiosensitive mutants of Saccharomyces cerevisiae yeasts].

    Science.gov (United States)

    Zakharov, I A; Kasinova, G V; Koval'tsova, S V

    1983-01-01

    The effect of UV- and gamma-irradiation on the survival and intragenic mitotic recombination (gene conversion) of 5 radiosensitive mutants was studied in comparison with the wild type. The level of spontaneous conversion was similar for RAD, rad2 and rad15, mutations xrs2 and xrs4 increasing and rad54 significantly decreasing it. The frequency of conversion induced by UV-light was greater in rad2, rad15 and xrs2 mutants and lower in xrs4, as compared to RAD. Gamma-irradiation caused induction of gene conversion with an equal frequency in RAD, rad2, rad15. Xrs2 and xrs4 mutations slightly decreased gamma-induced conversion. In rad54 mutant, UV-and gamma-induced conversion was practically absent. In the wild type yeast, a diploid strain is more resistant than a haploid, whereas in rad54 a diploid strain has the same or an increased sensitivity, as compared to a haploid strain (the "inverse ploidy effect"). This effect and also the block of induced mitotic recombination caused by rad54 indicate the presence in the yeast Saccharomyces cerevisiae of repair pathways of UV- and gamma-induced damages acting in diploid cells and realised by recombination. The data obtained as a result of many years' investigation of genetic effects in radiosensitive mutants of yeast are summarised and considered.

  12. Kefir drink causes a significant yet similar improvement in serum lipid profile, compared with low-fat milk, in a dairy-rich diet in overweight or obese premenopausal women: A randomized controlled trial.

    Science.gov (United States)

    Fathi, Yasamin; Ghodrati, Naeimeh; Zibaeenezhad, Mohammad-Javad; Faghih, Shiva

    Controversy exists as to whether the lipid-lowering properties of kefir drink (a fermented probiotic dairy product) in animal models could be replicated in humans. To assess and compare the potential lipid-lowering effects of kefir drink with low-fat milk in a dairy-rich diet in overweight or obese premenopausal women. In this 8-week, single-center, multiarm, parallel-group, outpatient, randomized controlled trial, 75 eligible Iranian women aged 25 to 45 years were randomly allocated to kefir, milk, or control groups. Women in the control group received a weight-maintenance diet containing 2 servings/d of low-fat dairy products, whereas subjects in the milk and kefir groups received a similar diet containing 2 additional servings/d (a total of 4 servings/d) of dairy products from low-fat milk or kefir drink, respectively. At baseline and study end point, serum levels/ratios of total cholesterol (TC), low- and high-density lipoprotein cholesterol (LDLC and HDLC), triglyceride, Non-HDLC, TC/HDLC, LDLC/HDLC, and triglyceride/LDLC were measured as outcome measures. After 8 weeks, subjects in the kefir group had significantly lower serum levels/ratios of lipoproteins than those in the control group (mean between-group differences were -10.4 mg/dL, -9.7 mg/dL, -11.5 mg/dL, -0.4, and -0.3 for TC, LDLC, non-HDLC, TC/HDLC, and LDLC/HDLC, respectively; all P < .05). Similar results were observed in the milk group. However, no such significant differences were found between the kefir and milk groups. Kefir drink causes a significant yet similar improvement in serum lipid profile, compared with low-fat milk, in a dairy-rich diet in overweight or obese premenopausal women. Copyright © 2016 National Lipid Association. Published by Elsevier Inc. All rights reserved.

  13. Regulation of chloroplast biogenesis: the immutans mutant of Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Rodermel, Steven

    2015-11-16

    The immutans (im) variegation mutant of Arabidopsis is an ideal model to gain insight into factors that control chloroplast biogenesis. im defines the gene for PTOX, a plastoquinol terminal oxidase that participates in control of thylakoid redox. Here, we report that the im defect can be suppressed during the late stages of plant development by gigantea (gi2), which defines the gene for GIGANTEA (GI), a central component of the circadian clock that plays a poorly-understood role in diverse plant developmental processes. imgi2 mutants are late-flowering and display other well-known phenotypes associated with gi2, such as starch accumulation and resistance to oxidative stress. We show that the restoration of chloroplast biogenesis in imgi2 is caused by a developmental-specific de-repression of cytokinin signaling that involves crosstalk with signaling pathways mediated by gibberellin (GA) and SPINDLY (SPY), a GA response inhibitor. Suppression of the plastid defect in imgi2 is likely caused by a relaxation of excitation pressures in developing plastids by factors contributed by gi2, including enhanced rates of photosynthesis and increased resistance to oxidative stress. Interestingly, the suppression phenotype of imgi can be mimicked by crossing im with the starch accumulation mutant, sex1, perhaps because sex1 utilizes pathways similar to gi. We conclude that our studies provide a direct genetic linkage between GIGANTEA and chloroplast biogenesis, and we construct a model of interactions between signaling pathways mediated by gi, GA, SPY, cytokinins, and sex1 that are required for chloroplast biogenesis.

  14. Characteristics and genetic mapping of a lesion mimic mutant pl(t) in japonica rice variety zhejing 22

    International Nuclear Information System (INIS)

    Chen Pingping; Zhang Xiaoming; Ye Shenghai; Zhao Ningchun; Lu Yanting; Liu Heqin; Jin Qingsheng; Yang Ling

    2010-01-01

    A lesion mimic mutant,obtained by radiation mutagenesis on the seeds of a japonica rice variety Zhejing 22, exhibited a lesion mimic phenotype during the whole growth stage under different environments. Genetic analysis indicated that the mutant trait was controlled by a single recessive gene named spl (t). Relying on simple sequence repeat (SSR) and recessive class analysis method to map the spl (t) gene with a F 2 population was constructed by crossing the mutant spl (t) with Zhenshan 97B.spl (t) was mapped in the interval of 0.8cM between RM7195 and RM27929 near centromere region on the short arm of chromosome 12.Blue trypan dye analyses indicated that the lesion mimic trait of the mutant was caused by the programmer cell death. Further study showed that the programmer cell death was caused by H 2 O 2 oxidative burst. By inoculation of bacterial leaf blight and blast strains, the resistances of the mutant were similar to the wild variety Zhejing 22. (authors)

  15. Photorepair mutants of Arabidopsis

    International Nuclear Information System (INIS)

    Jiang, C.Z.; Yee, J.; Mitchell, D.L.; Britt, A.B.

    1997-01-01

    UV radiation induces two major DNA damage products, the cyclobutane pyrimidine dimer (CPD) and, at a lower frequency, the pyrimidine (6-4) pyrimidinone dimer (6-4 product). Although Escherichia coli and Saccharomyces cerevisiae produce a CPD-specific photolyase that eliminates only this class of dimer, Arabidopsis thaliana, Drosophila melanogaster, Crotalus atrox, and Xenopus laevis have recently been shown to photoreactivate both CPDs and 6-4 products. We describe the isolation and characterization of two new classes of mutants of Arabidopsis, termed uvr2 and uvr3, that are defective in the photoreactivation of CPDs and 6-4 products, respectively. We demonstrate that the CPD photolyase mutation is genetically linked to a DNA sequence encoding a type II (metazoan) CPD photolyase. In addition, we are able to generate plants in which only CPDs or 6-4 products are photoreactivated in the nuclear genome by exposing these mutants to UV light and then allowing them to repair one or the other class of dimers. This provides us with a unique opportunity to study the biological consequences of each of these two major UV-induced photoproducts in an intact living system

  16. Construindo Marcas Mutantes

    Directory of Open Access Journals (Sweden)

    Elizete De Azevedo Kreutz

    2012-09-01

    Full Text Available O presente artigo é o resultado de estudos realizados desde 2000 e busca instrumentalizar os proñssionals para a construção de Marcas Mutantes, que é   uma tendência contemporânea nas estratégias comunicacionais e de branding. Embora esta estratégia ainda não esteja consolidada, observamos que a mesma tem obtido um crescimento constante e tem sido adotadas pelas mais diferentes categorias de marcas e não apenas por aquelas direcionadas aos jovens, ao esporte, ao entretenimento, como era no principia. Com base na Hermenêutica de Profundidade de Thompson (1995, alicerçada nas pesquisas bibliográficas, de intemet, entrevistas e análise semiótica, desenhamos um método de construção de Marcas Mutantes dividido em sete fases. Como resultado, esperamos que este estudo possa auxiliar na compreensão dos processos envolvidos, ao mesmo tempo que provoque a discussão sobreo mesmo e, por consequência, o seu aprimoramento.

  17. Ascertainment of the effect of differential growth rates of mutants on observed mutant frequencies in X-irradiated mammalian cells

    International Nuclear Information System (INIS)

    Knaap, A.G.A.C.; Simons, J.W.I.M.

    1983-01-01

    As it is not known to what extent differential growth rates of induced mutants lead to over- and under-representation of mutants in treated populations and thereby affect the determination of mutant frequencies, the mutation induction in X-irradiated L5178Y mouse lymphoma cells was determined via two methods. The first method involves the standard protocol which may suffer from the effect of differential growth rates, while the second method is based upon the fluctuation test in which the differential growth rates can be actually measured. It appeared that the standard protocol led to a mutant frequency that was similar to the mutant frequency determined in the fluctuation test. Therefore, the standard protocol appears to lead to only a minor under-estimation if any. Substantial heterogeneity in growth rates of induced mutants was observed, but the mutants with a selective advantage appear largely to compensate for the mutants that are lost because of selective disadvantage. It was calculated that the chance for isolating the same mutant twice from a treated population had been increased 2.2-fold because of the observed differential growth rates. (orig./AJ)

  18. Double-strand break repair and G2 block in Chinese hamster ovary cells and their radiosensitive mutants

    International Nuclear Information System (INIS)

    Weibezahn, K.F.; Lohrer, H.; Herrlich, P.

    1985-01-01

    Two X-ray-sensitive mutants of the CHO K1 cell line were examined for their cell-cycle progression after irradiation with γ-rays, and for their ability to rejoin double-strand breaks (DSBs) as detected by neutral filter elution. Both mutants were impaired in DSB rejoining and both were irreversibly blocked in the G 2 phase of the cell cycle as determined by cytofluorometry. From one mutant the authors have isolated several revertants. The revertants stem from genomic DNA transfection experiments and may have been caused by gene uptake. All revertants survived γ-irradiation as did the wild-type CHO line. One of them has been examined for its ability to rejoin DSBs and was found to be similar to the wild type. (Auth.)

  19. Double-strand break repair and G/sub 2/ block in Chinese hamster ovary cells and their radiosensitive mutants

    Energy Technology Data Exchange (ETDEWEB)

    Weibezahn, K F; Lohrer, H; Herrlich, P [Kernforschungszentrum Karlsruhe G.m.b.H. (Germany, F.R.). Inst. fuer Genetik und Toxikologie

    1985-05-01

    Two X-ray-sensitive mutants of the CHO K1 cell line were examined for their cell-cycle progression after irradiation with ..gamma..-rays, and for their ability to rejoin double-strand breaks (DSBs) as detected by neutral filter elution. Both mutants were impaired in DSB rejoining and both were irreversibly blocked in the G/sub 2/ phase of the cell cycle as determined by cytofluorometry. From one mutant the authors have isolated several revertants. The revertants stem from genomic DNA transfection experiments and may have been caused by gene uptake. All revertants survived ..gamma..-irradiation as did the wild-type CHO line. One of them has been examined for its ability to rejoin DSBs and was found to be similar to the wild type.

  20. Phage Pl mutants with altered transducing abilities for Escherichia coli

    International Nuclear Information System (INIS)

    Wall, J.D.; Harriman, P.D.

    1974-01-01

    A search was made for mutants of the coliphage P1 with altered transducing frequencies. A method was developed for the rapid assay of transducing frequencies in single plaques using prophage lambda as the transduced bacterial marker. This procedure selects for mutants altered in their ability to package host DNA. Mutants with 5 to 10 times higher or 10 to 20 times lower frequencies than those of wild-type P1 were found. Not only are the markers used for the detection of the mutants affected, but all other markers are similarly affected (not always to the same extent). One of the high transducing frequency mutants is a suppressible amber, indicating that loss of a function increases P1's ability to package host DNA preferentially. (U.S.)

  1. The agronomic characters of a high protein rice mutant

    International Nuclear Information System (INIS)

    Harn, C.; Won, J.L.; Choi, K.T.

    1975-01-01

    Mutant lines (M 5 -M 9 ) of macro-phenotypic traits from several varieties were screened for the protein content. Mutant 398 (M 9 ) is one of the high protein mutants selected from Hokwang. Three years' tests revealed that it has a high protein line under any condition of cultivation. Except for early maturity and short culmness, other agronomic and yield characters were similar to the original variety. There was no difference between the mutant 398 and its mother variety in grain shape and weight, and also the size and protein content of the embryo. The high protein content of the mutant is attributable to the increase of protein in the endosperm. About 150 normal-looking or a few days-earlier-maturing selections were made from Jinheung variety in the M 3 and screened for protein. Promising lines in terms of the plant type, yield and protein were obtained. (author)

  2. Molecular Genetic Identification Of Some Flax Mutants

    International Nuclear Information System (INIS)

    AMER, I.M.; MOUSTAFA, H.A.M.

    2009-01-01

    Five flax genotypes (Linum usitatissimum L.) i.e., commercial cultivar Sakha 2, the mother variety Giza 4 and three mutant types induced by gamma rays, were screened for their salinity tolerance in field experiments (salinity concentration was 8600 and 8300 ppm for soil and irrigation water, respectively). Mutation 6 was the most salt tolerant as compared to the other four genotypes.RAPD technique was used to detect some molecular markers associated with salt tolerance in flax (Mut 6), RAPD-PCR results using 12 random primers exhibited 149 amplified fragments; 91.9% of them were polymorphic and twelve molecular markers (8.1%) for salt tolerant (mutant 6) were identified with molecular size ranged from 191 to 4159 bp and only eight primers successes to amplify these specific markers. Concerning the other mutants, Mut 15 and Mut 25 exhibited 4.3% and 16.2% specific markers, respectively. The induced mutants exhibited genetic similarity to the parent variety were about 51%, 58.3% and 61.1% for Mut 25, Mut 6 and Mut 15, respectively. These specific markers (SM) are used for identification of the induced mutations and it is important for new variety registration.

  3. Study on homologous series of induced early mutants in Indica rice Ⅱ. the relationship between the homologous series of early mutants induced and the ecotype in Indica rice

    International Nuclear Information System (INIS)

    Chen Xiulan; Yang Hefeng; He Zhentian; Han Yuepeng; Liu Xueyu

    2001-01-01

    The induced mutation in light sensitivity of the Indica rice leads to induction of the homologous series of early mutants along with the variation of ecological character and the ecoclimate. The induction of mutants was closely related to the ecotype of Indica rice, the homologous series of early mutants in different level were derived from the different ecotype of the Indica rice, otherwise, the similar homologous series of early mutants were derived from the same ecotypic variety. The induction of the early ecotypic variety derived from the homologous series of early mutants provides the basis and possibility for accelerating the development of the new cultivars. (authors)

  4. Poliovirus Mutants Resistant to Neutralization with Soluble Cell Receptors

    Science.gov (United States)

    Kaplan, Gerardo; Peters, David; Racaniello, Vincent R.

    1990-12-01

    Poliovirus mutants resistant to neutralization with soluble cellular receptor were isolated. Replication of soluble receptor-resistant (srr) mutants was blocked by a monoclonal antibody directed against the HeLa cell receptor for poliovirus, indicating that the mutants use this receptor to enter cells. The srr mutants showed reduced binding to HeLa cells and cell membranes. However, the reduced binding phenotype did not have a major impact on viral replication, as judged by plaque size and one-step growth curves. These results suggest that the use of soluble receptors as antiviral agents could lead to the selection of neutralization-resistant mutants that are able to bind cell surface receptors, replicate, and cause disease.

  5. Development and release of gamma ray induced sesame mutant ANK-S2 in Sri Lanka

    International Nuclear Information System (INIS)

    Weerasena, L.A.; Bandara, Priyanthi; Pathirana, R.

    2001-01-01

    Epiphytotic conditions and lack of resistant germplasm in sesame (Sesamum indicum L.) prompted the use of mutation induction techniques to develop a variety resistant to Phytophthora blight caused by Phytophthora nicotianae var. parasitica. Dry seeds of three varieties were irradiated with six doses of 60 Co gamma rays in the range 100-700 Gy. The mutant line 182/3 of variety MI-3 selected from 200 Gy dose treatment in M 2 showed tolerance to the disease in subsequent testing at Angunakolapelessa in the disease nursery. The mutant line was tested in the major yield trial, National Co-ordinated Variety Trials and in the National Co-ordinated Variety Adaptability Trials. It was superior to MI-3 in yield and plant survival during the seasons favouring development of the disease and was similar to MI-3 and other recommended varieties in other seasons. The mutant has cream colour seeds, branched stem, and recorded 1890 kg/ha at Girandurukotte, 1593 kg ha -1 at Maha Illuppallama and 1151 kg/ha at Angunakolapelessa under rainfed conditions. The mutant was released as ANK-S2 in 1993 and may be used to increase the declining sesame area due to low yield of existing varieties and their susceptibility to disease. It should serve as a valuable parent material in cross-breeding programmes too. (author)

  6. Effects of ion beam irradiation on size of mutant sector and genetic damage in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Hase, Yoshihiro, E-mail: hase.yoshihiro@qst.go.jp [Takasaki Advanced Radiation Research Institute, National Institutes for Quantum and Radiological Science and Technology (QST), 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Nozawa, Shigeki [Takasaki Advanced Radiation Research Institute, National Institutes for Quantum and Radiological Science and Technology (QST), 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Narumi, Issay [Faculty of Life Sciences, Toyo University, 1-1-1 Izumino, Itakura, Gunma 374-0193 (Japan); Oono, Yutaka [Takasaki Advanced Radiation Research Institute, National Institutes for Quantum and Radiological Science and Technology (QST), 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2017-01-15

    Size of mutant sector and genetic damage were evaluated in Arabidopsis to further our understanding of effective ion beam use in plant mutation breeding. Arabidopsis seeds, heterozygous for the GLABRA1 (GL1) gene (GL1/gl1-1), were irradiated with 15.8 MeV/u neon ions (mean linear energy transfer (LET): 352 keV/μm), 17.3 MeV/u carbon ions (113 keV/μm), or {sup 60}Co gamma rays. The frequency and size of glabrous sectors generated because of inactivation of the GL1 allele were examined. The frequency and overall size of large deletions were evaluated based on the loss of heterozygosity of DNA markers using DNA isolated from glabrous tissue. Irrespective of the radiation properties, plants with mutant sectors were obtained at similar frequencies at the same effective dosage necessary for survival reduction. Ion beams tended to induce larger mutant sectors than gamma rays. The frequency of large deletions (>several kbp) increased as the LET value increased, with chromosome regions larger than 100 kbp lost in most large deletions. The distorted segregation ratio of glabrous plants in the progenies of irradiated GL1/gl1-1 plants suggested frequent occurrence of chromosome rearrangement, especially those subjected to neon ions. Exposure to ion beams with moderate LET values (30–110 keV/μm) is thought effective for inducing mutant sectors without causing extensive genetic damage.

  7. Evaluation of tall rice mutant

    International Nuclear Information System (INIS)

    Hakim, L.; Azam, M.A.; Miah, A.J.; Mansur, M.A.; Akanda, H.R.

    1989-01-01

    One tall mutant (Mut NS1) of rice variety Nizersail was put to multilocation on-farm trial. It showed improvement over the parent in respect of by earlier maturity and higher grain yield at all locations and thus it appears as an improved mutant of Nizersail. (author). 6 refs

  8. Homologous series of induced early mutants in indican rice. Pt.1. The production of homologous series of early mutants

    International Nuclear Information System (INIS)

    Chen Xiulan; Yang Hefeng; He Zhentian; Han Yuepeng; Liu Xueyu

    1999-01-01

    The percentage of homologous series of early mutants induced from the same Indican rice variety were almost the same (1.37%∼1.64%) in 1983∼1993, but the ones from the different eco-typical varieties were different. The early variety was 0.73%, the mid variety was 1.51%, and the late variety was 1.97%. The percentage of homologous series of early mutants from the varieties with the same pedigree and relationship were similar, but the one from the cog nation were lower than those from distant varieties. There are basic laws and characters in the homologous series of early mutants: 1. The inhibited phenotype is the basic of the homologous series of early mutants; 2. The production of the homologous series of early mutants is closely related with the growing period of the parent; 3. The parallel mutation of the stem and leaves are simultaneously happened with the variation of early or late maturing; 4. The occurrence of the homologous series of early mutants is in a state of imbalance. According to the law of parallel variability, the production of homologous series of early mutants can be predicted as long as the parents' classification of plant, pedigree and ecological type are identified. Therefore, the early breeding can be guided by the law of homologous series of early mutants

  9. Methods of producing protoporphyrin IX and bacterial mutants therefor

    Science.gov (United States)

    Zhou, Jizhong; Qiu, Dongru; He, Zhili; Xie, Ming

    2016-03-01

    The presently disclosed inventive concepts are directed in certain embodiments to a method of producing protoporphyrin IX by (1) cultivating a strain of Shewanella bacteria in a culture medium under conditions suitable for growth thereof, and (2) recovering the protoporphyrin IX from the culture medium. The strain of Shewanella bacteria comprises at least one mutant hemH gene which is incapable of normal expression, thereby causing an accumulation of protoporphyrin IX. In certain embodiments of the method, the strain of Shewanella bacteria is a strain of S. loihica, and more specifically may be S. loihica PV-4. In certain embodiments, the mutant hemH gene of the strain of Shewanella bacteria may be a mutant of shew_2229 and/or of shew_1140. In other embodiments, the presently disclosed inventive concepts are directed to mutant strains of Shewanella bacteria having at least one mutant hemH gene which is incapable of normal expression, thereby causing an accumulation of protoporphyrin IX during cultivation of the bacteria. In certain embodiments the strain of Shewanella bacteria is a strain of S. loihica, and more specifically may be S. loihica PV-4. In certain embodiments, the mutant hemH gene of the strain of Shewanella bacteria may be a mutant of shew_2229 and/or shew_1140.

  10. High yielding small grain mutant of rice variety Pankaj

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1987-07-01

    Full text: By treatment with EMS a mutant has been produced from the variety Pankaj which has better tillering, longer panicle and more grains per panicle. In multilocation trials at Burdwan, Suri and Rampurhat in West Bengal it yielded significantly more than Pankaj and Mahsuri at all locations, with a mean 5.2t. The mutant named BU 79 would be a suitable substitute for Pankaj and similar long-duration rices. (author)

  11. Structural, stability, dynamic and binding properties of the ALS-causing T46I mutant of the hVAPB MSP domain as revealed by NMR and MD simulations.

    Directory of Open Access Journals (Sweden)

    Shixiong Lua

    Full Text Available T46I is the second mutation on the hVAPB MSP domain which was recently identified from non-Brazilian kindred to cause a familial amyotrophic lateral sclerosis (ALS. Here using CD, NMR and molecular dynamics (MD simulations, we characterized the structure, stability, dynamics and binding capacity of the T46I-MSP domain. The results reveal: 1 unlike P56S which we previously showed to completely eliminate the native MSP structure, T46I leads to no significant disruption of the native secondary and tertiary structures, as evidenced from its far-UV CD spectrum, as well as Cα and Cβ NMR chemical shifts. 2 Nevertheless, T46I does result in a reduced thermodynamic stability and loss of the cooperative urea-unfolding transition. As such, the T46I-MSP domain is more prone to aggregation than WT at high protein concentrations and temperatures in vitro, which may become more severe in the crowded cellular environments. 3 T46I only causes a 3-fold affinity reduction to the Nir2 peptide, but a significant elimination of its binding to EphA4. 4 EphA4 and Nir2 peptide appear to have overlapped binding interfaces on the MSP domain, which strongly implies that two signaling networks may have a functional interplay in vivo. 5 As explored by both H/D exchange and MD simulations, the MSP domain is very dynamic, with most loop residues and many residues on secondary structures highly fluctuated or/and exposed to bulk solvent. Although T46I does not alter overall dynamics, it does trigger increased dynamics of several local regions of the MSP domain which are implicated in binding to EphA4 and Nir2 peptide. Our study provides the structural and dynamic understanding of the T46I-causing ALS; and strongly highlights the possibility that the interplay of two signaling networks mediated by the FFAT-containing proteins and Eph receptors may play a key role in ALS pathogenesis.

  12. Transcriptomic profiling-based mutant screen reveals three new transcription factors mediating menadione resistance in Neurospora crassa.

    Science.gov (United States)

    Zhu, Jufen; Yu, Xinxu; Xie, Baogui; Gu, Xiaokui; Zhang, Zhenying; Li, Shaojie

    2013-06-01

    To gain insight into the regulatory mechanisms of oxidative stress responses in filamentous fungi, the genome-wide transcriptional response of Neurospora crassa to menadione was analysed by digital gene expression (DGE) profiling, which identified 779 upregulated genes and 576 downregulated genes. Knockout mutants affecting 130 highly-upregulated genes were tested for menadione sensitivity, which revealed that loss of the transcription factor siderophore regulation (SRE) (a transcriptional repressor for siderophore biosynthesis), catatase-3, cytochrome c peroxidase or superoxide dismutase 1 copper chaperone causes hypersensitivity to menadione. Deletion of sre dramatically increased transcription of the siderophore biosynthesis gene ono and the siderophore iron transporter gene sit during menadione stress, suggesting that SRE is required for repression of iron uptake under oxidative stress conditions. Contrary to its phenotype, the sre deletion mutant showed higher transcriptional levels of genes encoding reactive oxygen species (ROS) scavengers than wild type during menadione stress, which implies that the mutant suffers a higher level of oxidative stress than wild type. Uncontrolled iron uptake in the sre mutant might exacerbate cellular oxidative stress. This is the first report of a negative regulator of iron assimilation participating in the fungal oxidative stress response. In addition to SRE, eight other transcription factor genes were also menadione-responsive but their single gene knockout mutants showed wild-type menadione sensitivity. Two of them, named as mit-2 (menadione induced transcription factor-2) and mit-4 (menadione induced transcription factor-4), were selected for double mutant analysis. The double mutant was hypersensitive to menadione. Similarly, the double mutation of mit-2 and sre also had additive effects on menadione sensitivity, suggesting multiple transcription factors mediate oxidative stress resistance in an additive manner

  13. Human liver cell trafficking mutants: characterization and whole exome sequencing.

    Directory of Open Access Journals (Sweden)

    Fei Yuan

    Full Text Available The HuH7 liver cell mutant Trf1 is defective in membrane trafficking and is complemented by the casein kinase 2α subunit CK2α''. Here we identify characteristic morphologies, trafficking and mutational changes in six additional HuH7 mutants Trf2-Trf7. Trf1 cells were previously shown to be severely defective in gap junction functions. Using a Lucifer yellow transfer assay, remarkable attenuation of gap junction communication was revealed in each of the mutants Trf2-Trf7. Electron microscopy and light microscopy of thiamine pyrophosphatase showed that several mutants exhibited fragmented Golgi apparatus cisternae compared to parental HuH7 cells. Intracellular trafficking was investigated using assays of transferrin endocytosis and recycling and VSV G secretion. Surface binding of transferrin was reduced in all six Trf2-Trf7 mutants, which generally correlated with the degree of reduced expression of the transferrin receptor at the cell surface. The mutants displayed the same transferrin influx rates as HuH7, and for efflux rate, only Trf6 differed, having a slower transferrin efflux rate than HuH7. The kinetics of VSV G transport along the exocytic pathway were altered in Trf2 and Trf5 mutants. Genetic changes unique to particular Trf mutants were identified by exome sequencing, and one was investigated in depth. The novel mutation Ile34Phe in the GTPase RAB22A was identified in Trf4. RNA interference knockdown of RAB22A or overexpression of RAB22AI34F in HuH7 cells caused phenotypic changes characteristic of the Trf4 mutant. In addition, the Ile34Phe mutation reduced both guanine nucleotide binding and hydrolysis activities of RAB22A. Thus, the RAB22A Ile34Phe mutation appears to contribute to the Trf4 mutant phenotype.

  14. The Swedish mutant barley collection

    International Nuclear Information System (INIS)

    1989-01-01

    Full text: The Swedish mutation research programme in barley began about 50 years ago and has mainly been carried out at Svaloev in co-operation with the institute of Genetics at the University of Lund. The collection has been produced from different Swedish high-yielding spring barley varieties, using the following mutagens: X-rays, neutrons, several organic chemical compounds such as ethyleneimine, several sulfonate derivatives and the inorganic chemical mutagen sodium azide. Nearly 10,000 barley mutants are stored in the Nordic Gene Bank and documented in databases developed by Udda Lundquist, Svaloev AB. The collection consists of the following nine categories with 94 different types of mutants: 1. Mutants with changes in the spike and spikelets; 2. Changes in culm length and culm composition; 3. Changes in growth types; 4. Physiological mutants; 5. Changes in awns; 6. Changes in seed size and shape; 7. Changes in leaf blades; 8. Changes in anthocyanin and colour; 9. Resistance to barley powdery mildew. Barley is one of the most thoroughly investigated crops in terms of induction of mutations and mutation genetics. So far, about half of the mutants stored at the Nordic Gene Bank, have been analysed genetically; They constitute, however, only a minority of the 94 different mutant types. The genetic analyses have given valuable insights into the mutation process but also into the genetic architecture of various characters. A number of mutants of two-row barley have been registered and commercially released. One of the earliest released, Mari, an early maturing, daylength neutral, straw stiff mutant, is still grown in Iceland. The Swedish mutation material has been used in Sweden, but also in other countries, such as Denmark, Germany, and USA, for various studies providing a better understanding of the barley genome. The collection will be immensely valuable for future molecular genetical analyses of clone mutant genes. (author)

  15. The Swedish mutant barley collection

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1989-07-01

    Full text: The Swedish mutation research programme in barley began about 50 years ago and has mainly been carried out at Svaloev in co-operation with the institute of Genetics at the University of Lund. The collection has been produced from different Swedish high-yielding spring barley varieties, using the following mutagens: X-rays, neutrons, several organic chemical compounds such as ethyleneimine, several sulfonate derivatives and the inorganic chemical mutagen sodium azide. Nearly 10,000 barley mutants are stored in the Nordic Gene Bank and documented in databases developed by Udda Lundquist, Svaloev AB. The collection consists of the following nine categories with 94 different types of mutants: 1. Mutants with changes in the spike and spikelets; 2. Changes in culm length and culm composition; 3. Changes in growth types; 4. Physiological mutants; 5. Changes in awns; 6. Changes in seed size and shape; 7. Changes in leaf blades; 8. Changes in anthocyanin and colour; 9. Resistance to barley powdery mildew. Barley is one of the most thoroughly investigated crops in terms of induction of mutations and mutation genetics. So far, about half of the mutants stored at the Nordic Gene Bank, have been analysed genetically; They constitute, however, only a minority of the 94 different mutant types. The genetic analyses have given valuable insights into the mutation process but also into the genetic architecture of various characters. A number of mutants of two-row barley have been registered and commercially released. One of the earliest released, Mari, an early maturing, daylength neutral, straw stiff mutant, is still grown in Iceland. The Swedish mutation material has been used in Sweden, but also in other countries, such as Denmark, Germany, and USA, for various studies providing a better understanding of the barley genome. The collection will be immensely valuable for future molecular genetical analyses of clone mutant genes. (author)

  16. Finding Inhibitors of Mutant Superoxide Dismutase-1 for Amyotrophic Lateral Sclerosis Therapy from Traditional Chinese Medicine

    Directory of Open Access Journals (Sweden)

    Hung-Jin Huang

    2014-01-01

    Full Text Available Superoxide dismutase type 1 (SOD1 mutations cause protein aggregation and decrease protein stability, which are linked to amyotrophic lateral sclerosis (ALS disease. This research utilizes the world’s largest traditional Chinese medicine (TCM database to search novel inhibitors of mutant SOD1, and molecular dynamics (MD simulations were used to analyze the stability of protein that interacted with docked ligands. Docking results show that hesperidin and 2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucoside (THSG have high affinity to mutant SOD1 and then dopamine. For MD simulation analysis, hesperidin and THSG displayed similar value of RMSD with dopamine, and the migration analysis reveals stable fluctuation at the end of MD simulation time. Interestingly, distance between the protein and ligand has distinct difference, and hesperidin changes the position from initial binding site to the other place. In flexibility of residues analysis, the secondary structure among all complexes does not change, indicating that the structure are not affect ligand binding. The binding poses of hesperidin and THSG are similar to dopamine after molecular simulation. Our result indicated that hesperidin and THSG might be potential lead compound to design inhibitors of mutant SOD1 for ALS therapy.

  17. Convergent mechanisms favor fast amyloid formation in two lambda 6a Ig light chain mutants.

    Science.gov (United States)

    Valdés-García, Gilberto; Millán-Pacheco, César; Pastor, Nina

    2017-08-01

    Extracellular deposition as amyloids of immunoglobulin light chains causes light chain amyloidosis. Among the light chain families, lambda 6a is one of the most frequent in light chain amyloidosis patients. Its germline protein, 6aJL2, and point mutants, R24G and P7S, are good models to study fibrillogenesis, because their stability and fibril formation characteristics have been described. Both mutations make the germline protein unstable and speed up its ability to aggregate. To date, there is no molecular mechanism that explains how these differences in amyloidogenesis can arise from a single mutation. To look into the structural and dynamical differences in the native state of these proteins, we carried out molecular dynamics simulations at room temperature. Despite the structural similarity of the germline protein and the mutants, we found differences in their dynamical signatures that explain the mutants' increased tendency to form amyloids. The contact network alterations caused by the mutations, though different, converge in affecting two anti-aggregation motifs present in light chain variable domains, suggesting a different starting point for aggregation in lambda chains compared to kappa chains. © 2017 Wiley Periodicals, Inc.

  18. Genetic analysis of DNA repair in Aspergillus: evidence for different types of MMS-sensitive hyperrec mutants.

    Science.gov (United States)

    Käfer, E; Mayor, O

    1986-07-01

    To identify genes which affect DNA repair and possibly recombination in Aspergillus nidulans, mutants hypersensitive to methyl methanesulphonate (MMS) were induced with ultraviolet light (UV) or gamma-rays. About half of them contained associated translocations and many were hypersensitive to UV and/or defective in meiosis. Two are alleles of the known uvsB gene while most others define new genes. In addition, among available uvs mutants many were found to be MMS-sensitive. Some of the various uncharacterized ones were identified as alleles of known uvs, but 5 of them were mapped in 2 new genes, uvsH and uvsJ. To identify functional and epistatic groups, mutants from each uvs gene were tested for effects on recombination and mutation, and double mutant uvs strains were compared for UV survival to their component single mutant strains. 3 epistatic pairs were identified, (1) uvsF and H, (2) uvsB and D, and (3) uvsC and E. Conclusive interpair tests were difficult, because such double mutant combinations were frequently lethal or nearly so. The first pair, uvsF and H, shared some of the properties of excision-defective mutants, both uvs being very highly sensitive to UV for mutation as well as survival. But unlike such mutants, uvsH was also sensitive to gamma-rays and defective in meiosis. Both uvs showed normal levels of meiotic recombination, but greatly increased spontaneous mitotic crossing-over, being the most "hyperrec" types among all uvs. The second pair, uvsB and uvsC, which was similarly hyperrec showed only slight increases of UV-induced mutation (less than 2-fold). As a main effect, these uvs caused very high frequencies of unbalanced, unstable segregants from diploid conidia (30 X), but few of these were recognizable aneuploids. The third pair, uvsC and E, which are known to be rec- for gene conversion, caused reduced mitotic crossing-over in diploids and increased levels of haploid segregants. These mutants are spontaneous mutators, but showed less UV

  19. Progranulin is neurotrophic in vivo and protects against a mutant TDP-43 induced axonopathy.

    Directory of Open Access Journals (Sweden)

    Angela S Laird

    Full Text Available Mislocalization, aberrant processing and aggregation of TAR DNA-binding protein 43 (TDP-43 is found in the neurons affected by two related diseases, amyotrophic lateral sclerosis (ALS and frontotemporal lobe dementia (FTLD. These TDP-43 abnormalities are seen when TDP-43 is mutated, such as in familial ALS, but also in FTLD, caused by null mutations in the progranulin gene. They are also found in many patients with sporadic ALS and FTLD, conditions in which only wild type TDP-43 is present. The common pathological hallmarks and symptomatic cross over between the two diseases suggest that TDP-43 and progranulin may be mechanistically linked. In this study we aimed to address this link by establishing whether overexpression of mutant TDP-43 or knock-down of progranulin in zebrafish embryos results in motor neuron phenotypes and whether human progranulin is neuroprotective against such phenotypes. Mutant TDP-43 (A315T mutation induced a motor axonopathy characterized by short axonal outgrowth and aberrant branching, similar, but more severe, than that induced by mutant SOD1. Knockdown of the two zebrafish progranulin genes, grna and grnb, produced a substantial decrease in axonal length, with knockdown of grna alone producing a greater decrease in axonal length than grnb. Progranulin overexpression rescued the axonopathy induced by progranulin knockdown. Interestingly, progranulin also rescued the mutant TDP-43 induced axonopathy, whilst it failed to affect the mutant SOD1-induced phenotype. TDP-43 was found to be nuclear in all conditions described. The findings described here demonstrate that progranulin is neuroprotective in vivo and may have therapeutic potential for at least some forms of motor neuron degeneration.

  20. Dipeptide repeat protein inclusions are rare in the spinal cord and almost absent from motor neurons in C9ORF72 mutant amyotrophic lateral sclerosis and are unlikely to cause their degeneration.

    Science.gov (United States)

    Gomez-Deza, Jorge; Lee, Youn-Bok; Troakes, Claire; Nolan, Matthew; Al-Sarraj, Safa; Gallo, Jean-Marc; Shaw, Christopher E

    2015-06-25

    Cytoplasmic TDP-43 inclusions are the pathological hallmark of amyotrophic lateral sclerosis (ALS) and tau-negative frontotemporal lobar dementia (FTLD). The G4C2 repeat mutation in C9ORF72 is the most common cause of ALS and FTLD in which, in addition to TDP-43 inclusions, five different di-peptide repeat (DPR) proteins have been identified. Di-peptide repeat proteins are translated in a non-canonical fashion from sense and antisense transcripts of the G4C2 repeat (GP, GA, GR, PA, PR). DPR inclusions are abundant in the cerebellum, as well as in the frontal and temporal lobes of ALS and FTLD patients and some are neurotoxic in a range of cellular and animal models, implying that DPR aggregation directly contributes to disease pathogenesis. Here we sought to quantify inclusions for each DPR and TDP-43 in ALS cases with and without the C9ORF72 mutation. We characterised the abundance of DPRs and their cellular location and compared this to cytoplasmic TDP-43 inclusions in order to explore the role of each inclusion in lower motor neuron degeneration. Spinal cord sections from ten cases positive for the C9ORF72 repeat expansion (ALS-C9+ve) and five cases that were not were probed by double immunofluorescence staining for individual DPRs and TDP-43. Inclusions immunoreactive for each of the DPRs were present in the spinal cord but they were rare or very rare in abundance (in descending order of frequency: GA, GP, GR, PA and PR). TDP-43 cytoplasmic inclusions were 45- to 750-fold more frequent than any DPR, and fewer than 4 % of DPR inclusions colocalized with TDP-43 inclusions. In motor neurons, a single cytoplasmic DPR inclusion was detected (0.1 %) in contrast to the 34 % of motor neurons that contained cytoplasmic TDP-43 inclusions. Furthermore, the number of TDP-43 inclusions in ALS cases with and without the C9ORF72 mutation was nearly identical. For all other neurodegenerative diseases, the neurotoxic protein aggregates are detected in the affected

  1. We Are All Mutants

    Science.gov (United States)

    Timson, David J.

    2017-01-01

    Mutations can cause genetic diseases and the vast majority of these have no effective treatment. They raise some difficult questions on the boundaries of science and social science. Selective breeding to "improve" the human race (eugenics) is often regarded as a Victorian relic or Nazi fantasy. Yet, three fetuses with Down syndrome are…

  2. New Similarity Functions

    DEFF Research Database (Denmark)

    Yazdani, Hossein; Ortiz-Arroyo, Daniel; Kwasnicka, Halina

    2016-01-01

    spaces, in addition to their similarity in the vector space. Prioritized Weighted Feature Distance (PWFD) works similarly as WFD, but provides the ability to give priorities to desirable features. The accuracy of the proposed functions are compared with other similarity functions on several data sets....... Our results show that the proposed functions work better than other methods proposed in the literature....

  3. Phoneme Similarity and Confusability

    Science.gov (United States)

    Bailey, T.M.; Hahn, U.

    2005-01-01

    Similarity between component speech sounds influences language processing in numerous ways. Explanation and detailed prediction of linguistic performance consequently requires an understanding of these basic similarities. The research reported in this paper contrasts two broad classes of approach to the issue of phoneme similarity-theoretically…

  4. Mutants of alfalfa mosaic virus

    International Nuclear Information System (INIS)

    Roosien, J.

    1983-01-01

    In this thesis the isolation and characterization of a number of mutants of alfalfa mosaic virus, a plant virus with a coat protein dependent genome, is described. Thermo-sensitive (ts) mutants were selected since, at least theoretically, ts mutations can be present in all virus coded functions. It was found that a high percentage of spontaneous mutants, isolated because of their aberrant symptoms, were ts. The majority of these isolates could grow at the non-permissive temperature in the presence of a single wild type (wt) component. To increase the mutation rate virus preparations were treated with several mutagens. After nitrous acid treatment or irradiation with ultraviolet light, an increase in the level of mutations was observed. UV irradiation was preferred since it did not require large amounts of purified viral components. During the preliminary characterization of potential ts mutants the author also obtained one structural and several symptom mutants which were analysed further (chapter 7, 8 and 9). The properties of the ts mutants are described in chapter 3-7. (Auth.)

  5. Allosteric Mutant IDH1 Inhibitors Reveal Mechanisms for IDH1 Mutant and Isoform Selectivity

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Xiaoling; Baird, Daniel; Bowen, Kimberly; Capka, Vladimir; Chen, Jinyun; Chenail, Gregg; Cho, YoungShin; Dooley, Julia; Farsidjani, Ali; Fortin, Pascal; Kohls, Darcy; Kulathila, Raviraj; Lin, Fallon; McKay, Daniel; Rodrigues, Lindsey; Sage, David; Touré, B. Barry; van der Plas, Simon; Wright, Kirk; Xu, Ming; Yin, Hong; Levell, Julian; Pagliarini, Raymond A. (Novartis)

    2017-03-01

    Oncogenic IDH1 and IDH2 mutations contribute to cancer via production of R-2-hydroxyglutarate (2-HG). Here, we characterize two structurally distinct mutant- and isoform-selective IDH1 inhibitors that inhibit 2-HG production. Both bind to an allosteric pocket on IDH1, yet shape it differently, highlighting the plasticity of this site. Oncogenic IDH1R132H mutation destabilizes an IDH1 “regulatory segment,” which otherwise restricts compound access to the allosteric pocket. Regulatory segment destabilization in wild-type IDH1 promotes inhibitor binding, suggesting that destabilization is critical for mutant selectivity. We also report crystal structures of oncogenic IDH2 mutant isoforms, highlighting the fact that the analogous segment of IDH2 is not similarly destabilized. This intrinsic stability of IDH2 may contribute to observed inhibitor IDH1 isoform selectivity. Moreover, discrete residues in the IDH1 allosteric pocket that differ from IDH2 may also guide IDH1 isoform selectivity. These data provide a deeper understanding of how IDH1 inhibitors achieve mutant and isoform selectivity.

  6. Promising semi-dwarf mutant in wheat variety K68

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, D [Banaras Hindu Univ. (India). Dept. of Genetics and Plant Breeding

    1977-04-01

    A semi-dwarf mutant (HUW-SDf 1) was induced from common wheat Var. K68 through the exposure of /sup 60/Co ..gamma..-rays at 15 kR. This mutant along with other induced mutants and control was assessed for yield components, yield and grain quality (M/sub 4/ generation); internode length reduction pattern and the yielding ability at three levels of nitrogen (M/sub 5/ generation). The mutant was significantly shorter in height and almost equal in tillers per plant and grains per spike to K68. However, it showed marked reduction in spike length and spikelets per spike. On the other hand, it possessed significantly higher (50.04 g) 1000-grain weight against control (41.15 g). The mutant gave 56.0% higher yield than the control. Grain quality studies indicated that the mutant possessed significantly higher (14.15%) total protein than K68. It was equally as good as K68 in lysine content. Pelshenke value (62.5 min) of the mutant indicated medium hard nature of gluten as compared to hard nature (198.0) of the control. The mutant showed 24.0% reduction in total culm length compared to K68. Reduction occurred due to maximum and almost equal reduction in 5th and 4th internodes (ca 34.0%) followed by 3rd, 2nd and 1st. The mutant showed similar yield and yield response to increasing nitrogen levels (80 to 160 kg per ha.) as for current commercial semi-dwarf varieties.

  7. Is auxin involved in the induction of genetic instability in barley homeotic double mutants?

    Science.gov (United States)

    Šiukšta, Raimondas; Vaitkūnienė, Virginija; Rančelis, Vytautas

    2018-02-01

    The triggers of genetic instability in barley homeotic double mutants are tweaky spike -type mutations associated with an auxin imbalance in separate spike phytomeres. Barley homeotic tweaky spike;Hooded (tw;Hd) double mutants are characterized by an inherited instability of spike and flower development, which is absent in the single parental constituents. The aim of the present study was to show that the trigger of genetic instability in the double mutants is the tw mutations, which are associated with an auxin imbalance in the developing spikes. Their pleiotropic effects on genes related to spike/flower development may cause the genetic instability of double mutants. The study of four double-mutant groups composed of different mutant alleles showed that the instability arose only if the mutant allele tw was a constituent of the double mutants. Application of auxin inhibitors and 2,4-dichlorophenoxyacetic acid (2,4-D) demonstrated the relationship of the instability of the double mutants and the phenotype of the tw mutants to auxin imbalance. 2,4-D induced phenocopies of the tw mutation in wild-type plants and rescued the phenotypes of three allelic tw mutants. The differential display (dd-PCR) method allowed the identification of several putative candidate genes in tw that may be responsible for the initiation of instability in the double mutants by pleiotropic variations of their expression in the tw mutant associated with auxin imbalance in the developing spikes. The results of the present study linked the genetic instability of homeotic double mutants with an auxin imbalance caused by one of the constituents (tw). The genetic instability of the double mutants in relation to auxin imbalance was studied for the first time. A matrocliny on instability expression was also observed.

  8. Neurodegeneration in drop-dead mutant drosophila melanogaster is associated with the respiratory system but not with Hypoxia.

    Directory of Open Access Journals (Sweden)

    Christine Lynn Sansone

    Full Text Available Mutations in the gene drop-dead (drd cause diverse phenotypes in adult Drosophila melanogaster including early lethality, neurodegeneration, tracheal defects, gut dysfunction, reduced body mass, and female sterility. Despite the identification of the drd gene itself, the causes of early lethality and neurodegeneration in the mutant flies remain unknown. To determine the pattern of drd expression associated with the neurodegenerative phenotype, knockdown of drd with various Gal4 drivers was performed. Early adult lethality and neurodegeneration were observed upon knockdown of drd in the tracheal system with two independent insertions of the breathless-Gal4 driver and upon knockdown in the tracheal system and elsewhere with the DJ717-Gal4 driver. Surprisingly, rescue of drd expression exclusively in the tracheae in otherwise mutant flies rescued the neurodegenerative phenotype but not adult lethality. Gut dysfunction, as measured by defecation rate, was not rescued in these flies, and gut function appeared normal upon tracheal-specific knockdown of drd. Finally, the hypothesis that tracheal dysfunction in drd mutants results in hypoxia was tested. Hypoxia-sensitive reporter transgenes (LDH-Gal4 and LDH-LacZ were placed on a drd mutant background, but enhanced expression of these reporters was not observed. In addition, manipulation of drd expression in the tracheae did not affect expression of the hypoxia-induced genes LDH, tango, and similar. Overall, these results indicate that there are at least two causes of adult lethality in drd mutants, that gut dysfunction and neurodegeneration are independent phenotypes, and that neurodegeneration is associated with tracheal expression of drd but not with hypoxia.

  9. Mutants induced in winter rye (Secale cereale L.): Short straw-mutant No. 2714 and late-senescence mutant

    Energy Technology Data Exchange (ETDEWEB)

    Muszynski, S; Darlewska, M [Department of Plant Breeding and Seed Science, Warsaw Agricultural University, Warsaw (Poland)

    1990-01-01

    Full text: Mutants were induced by treating dormant seeds with ionizing radiation (fast neutrons) or chemicals (N-nitroso-N-ethyl urea or sodium azide). Among several mutants obtained, of special value is the short-straw mutant No. 2714 and a late senescent mutant. (author)

  10. Histological changes in the rat brain and spinal cord following prolonged intracerebroventricular infusion of cerebrospinal fluid from amyotrophic lateral sclerosis patients are similar to those caused by the disease.

    Science.gov (United States)

    Gómez-Pinedo, U; Galán, L; Yañez, M; Matias-Guiu, J; Valencia, C; Guerrero-Sola, A; Lopez-Sosa, F; Brin, J R; Benito-Martin, M S; Leon-Espinosa, G; Vela-Souto, A; Lendinez, C; Guillamon-Vivancos, T; Matias-Guiu, J A; Arranz-Tagarro, J A; Barcia, J A; Garcia, A G

    2018-05-01

    Cerebrospinal fluid (CSF) from amyotrophic lateral sclerosis (ALS) patients induces cytotoxic effects in in vitro cultured motor neurons. We selected CSF with previously reported cytotoxic effects from 32 ALS patients. Twenty-eight adult male rats were intracerebroventricularly implanted with osmotic mini-pumps and divided into 3 groups: 9 rats injected with CSF from non-ALS patients, 15 rats injected with cytotoxic ALS-CSF, and 4 rats injected with a physiological saline solution. CSF was intracerebroventricularly and continuously infused for periods of 20 or 43days after implantation. We conducted clinical assessments and electromyographic examinations, and histological analyses were conducted in rats euthanised 20, 45, and 82days after surgery. Immunohistochemical studies revealed tissue damage with similar characteristics to those found in the sporadic forms of ALS, such as overexpression of cystatinC, transferrin, and TDP-43 protein in the cytoplasm. The earliest changes observed seemed to play a protective role due to the overexpression of peripherin, AKTpan, AKTphospho, and metallothioneins; this expression had diminished by the time we analysed rats euthanised on day 82, when an increase in apoptosis was observed. The first cellular changes identified were activated microglia followed by astrogliosis and overexpression of GFAP and S100B proteins. Our data suggest that ALS could spread through CSF and that intracerebroventricular administration of cytotoxic ALS-CSF provokes changes similar to those found in sporadic forms of the disease. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  11. Molecular similarity measures.

    Science.gov (United States)

    Maggiora, Gerald M; Shanmugasundaram, Veerabahu

    2011-01-01

    Molecular similarity is a pervasive concept in chemistry. It is essential to many aspects of chemical reasoning and analysis and is perhaps the fundamental assumption underlying medicinal chemistry. Dissimilarity, the complement of similarity, also plays a major role in a growing number of applications of molecular diversity in combinatorial chemistry, high-throughput screening, and related fields. How molecular information is represented, called the representation problem, is important to the type of molecular similarity analysis (MSA) that can be carried out in any given situation. In this work, four types of mathematical structure are used to represent molecular information: sets, graphs, vectors, and functions. Molecular similarity is a pairwise relationship that induces structure into sets of molecules, giving rise to the concept of chemical space. Although all three concepts - molecular similarity, molecular representation, and chemical space - are treated in this chapter, the emphasis is on molecular similarity measures. Similarity measures, also called similarity coefficients or indices, are functions that map pairs of compatible molecular representations that are of the same mathematical form into real numbers usually, but not always, lying on the unit interval. This chapter presents a somewhat pedagogical discussion of many types of molecular similarity measures, their strengths and limitations, and their relationship to one another. An expanded account of the material on chemical spaces presented in the first edition of this book is also provided. It includes a discussion of the topography of activity landscapes and the role that activity cliffs in these landscapes play in structure-activity studies.

  12. Analysis of STAT1 activation by six FGFR3 mutants associated with skeletal dysplasia undermines dominant role of STAT1 in FGFR3 signaling in cartilage.

    Directory of Open Access Journals (Sweden)

    Pavel Krejci

    Full Text Available Activating mutations in FGFR3 tyrosine kinase cause several forms of human skeletal dysplasia. Although the mechanisms of FGFR3 action in cartilage are not completely understood, it is believed that the STAT1 transcription factor plays a central role in pathogenic FGFR3 signaling. Here, we analyzed STAT1 activation by the N540K, G380R, R248C, Y373C, K650M and K650E-FGFR3 mutants associated with skeletal dysplasias. In a cell-free kinase assay, only K650M and K650E-FGFR3 caused activatory STAT1(Y701 phosphorylation. Similarly, in RCS chondrocytes, HeLa, and 293T cellular environments, only K650M and K650E-FGFR3 caused strong STAT1 activation. Other FGFR3 mutants caused weak (HeLa or no activation (293T and RCS. This contrasted with ERK MAP kinase activation, which was strongly induced by all six mutants and correlated with the inhibition of proliferation in RCS chondrocytes. Thus the ability to activate STAT1 appears restricted to the K650M and K650E-FGFR3 mutants, which however account for only a small minority of the FGFR3-related skeletal dysplasia cases. Other pathways such as ERK should therefore be considered as central to pathological FGFR3 signaling in cartilage.

  13. Similarity Measure of Graphs

    Directory of Open Access Journals (Sweden)

    Amine Labriji

    2017-07-01

    Full Text Available The topic of identifying the similarity of graphs was considered as highly recommended research field in the Web semantic, artificial intelligence, the shape recognition and information research. One of the fundamental problems of graph databases is finding similar graphs to a graph query. Existing approaches dealing with this problem are usually based on the nodes and arcs of the two graphs, regardless of parental semantic links. For instance, a common connection is not identified as being part of the similarity of two graphs in cases like two graphs without common concepts, the measure of similarity based on the union of two graphs, or the one based on the notion of maximum common sub-graph (SCM, or the distance of edition of graphs. This leads to an inadequate situation in the context of information research. To overcome this problem, we suggest a new measure of similarity between graphs, based on the similarity measure of Wu and Palmer. We have shown that this new measure satisfies the properties of a measure of similarities and we applied this new measure on examples. The results show that our measure provides a run time with a gain of time compared to existing approaches. In addition, we compared the relevance of the similarity values obtained, it appears that this new graphs measure is advantageous and  offers a contribution to solving the problem mentioned above.

  14. Processes of Similarity Judgment

    Science.gov (United States)

    Larkey, Levi B.; Markman, Arthur B.

    2005-01-01

    Similarity underlies fundamental cognitive capabilities such as memory, categorization, decision making, problem solving, and reasoning. Although recent approaches to similarity appreciate the structure of mental representations, they differ in the processes posited to operate over these representations. We present an experiment that…

  15. Judgments of brand similarity

    NARCIS (Netherlands)

    Bijmolt, THA; Wedel, M; Pieters, RGM; DeSarbo, WS

    This paper provides empirical insight into the way consumers make pairwise similarity judgments between brands, and how familiarity with the brands, serial position of the pair in a sequence, and the presentation format affect these judgments. Within the similarity judgment process both the

  16. Durable resistance to net blotch and agronomic performance in some barley mutants [Hordeum vulgare L.; Syria

    International Nuclear Information System (INIS)

    Arabi, M.I.E.

    2004-01-01

    Seeds from the net blotch (Pyrenophora teres) susceptible cultivar Thibaut were treated by gamma ray radiation and subsequently evaluated for reaction to the pathogen in the M2-M5 generations. Grain yield and agronomic characteristics of putative mutants were compared with Thibaut in two different locations. Genetic variation among some mutant lines/cv Thibaut was estimated using Amplified Fragment Length Polymorphism (AFLP) markers. Sixteen mutant lines and their mother cultivar Thibaut were analyzed with 14 EcoR1-Mse1 primer combinations. A total number of 504 AFLP bands were analyzed for each pair mutant/Thibaut. Narrow genetic variation among all genotypes was detected with an average of genetic similarity of 0.96. Cluster analysis with the entire AFLP data divided all genotypes into two major groups. The resistant mutant lines were grouped in one subcluster with 0.98 similarity index. Some resistant mutant lines to net blotch with good agronomic performances were produced [it

  17. Indy mutants: live long and prosper

    Directory of Open Access Journals (Sweden)

    Stewart eFrankel

    2012-02-01

    Full Text Available Indy encodes the fly homologue of a mammalian transporter of di and tricarboxylatecomponents of the Krebs cycle. Reduced expression of fly Indy or two of the C. elegansIndy homologs leads to an increase in life span. Fly and worm tissues that play key roles inintermediary metabolism are also the places where Indy genes are expressed. One of themouse homologs of Indy (mIndy is mainly expressed in the liver. It has been hypothesizedthat decreased INDY activity creates a state similar to caloric restriction (CR. Thishypothesis is supported by the physiological similarities between Indy mutant flies on highcalorie food and control flies on CR, such as increased physical activity and decreases inweight, egg production, triglyceride levels, starvation resistance, and insulin signaling. Inaddition, Indy mutant flies undergo changes in mitochondrial biogenesis also observed inCR animals. Recent findings with mIndy knockout mice support and extend the findingsfrom flies. mIndy-/- mice display an increase in hepatic mitochondrial biogenesis, lipidoxidation and decreased hepatic lipogenesis. When mIndy-/- mice are fed high calorie foodthey are protected from adiposity and insulin resistance. These findings point to INDY as apotential drug target for the treatment of metabolic syndrome, type 2 diabetes and obesity.

  18. The semantic similarity ensemble

    Directory of Open Access Journals (Sweden)

    Andrea Ballatore

    2013-12-01

    Full Text Available Computational measures of semantic similarity between geographic terms provide valuable support across geographic information retrieval, data mining, and information integration. To date, a wide variety of approaches to geo-semantic similarity have been devised. A judgment of similarity is not intrinsically right or wrong, but obtains a certain degree of cognitive plausibility, depending on how closely it mimics human behavior. Thus selecting the most appropriate measure for a specific task is a significant challenge. To address this issue, we make an analogy between computational similarity measures and soliciting domain expert opinions, which incorporate a subjective set of beliefs, perceptions, hypotheses, and epistemic biases. Following this analogy, we define the semantic similarity ensemble (SSE as a composition of different similarity measures, acting as a panel of experts having to reach a decision on the semantic similarity of a set of geographic terms. The approach is evaluated in comparison to human judgments, and results indicate that an SSE performs better than the average of its parts. Although the best member tends to outperform the ensemble, all ensembles outperform the average performance of each ensemble's member. Hence, in contexts where the best measure is unknown, the ensemble provides a more cognitively plausible approach.

  19. Larger aggregates of mutant seipin in Celia's Encephalopathy, a new protein misfolding neurodegenerative disease.

    Science.gov (United States)

    Ruiz-Riquelme, Alejandro; Sánchez-Iglesias, Sofía; Rábano, Alberto; Guillén-Navarro, Encarna; Domingo-Jiménez, Rosario; Ramos, Adriana; Rosa, Isaac; Senra, Ana; Nilsson, Peter; García, Ángel; Araújo-Vilar, David; Requena, Jesús R

    2015-11-01

    Celia's Encephalopathy (MIM #615924) is a recently discovered fatal neurodegenerative syndrome associated with a new BSCL2 mutation (c.985C>T) that results in an aberrant isoform of seipin (Celia seipin). This mutation is lethal in both homozygosity and compounded heterozygosity with a lipodystrophic BSCL2 mutation, resulting in a progressive encephalopathy with fatal outcomes at ages 6-8. Strikingly, heterozygous carriers are asymptomatic, conflicting with the gain of toxic function attributed to this mutation. Here we report new key insights about the molecular pathogenic mechanism of this new syndrome. Intranuclear inclusions containing mutant seipin were found in brain tissue from a homozygous patient suggesting a pathogenic mechanism similar to other neurodegenerative diseases featuring brain accumulation of aggregated, misfolded proteins. Sucrose gradient distribution showed that mutant seipin forms much larger aggregates as compared with wild type (wt) seipin, indicating an impaired oligomerization. On the other hand, the interaction between wt and Celia seipin confirmed by coimmunoprecipitation (CoIP) assays, together with the identification of mixed oligomers in sucrose gradient fractionation experiments can explain the lack of symptoms in heterozygous carriers. We propose that the increased aggregation and subsequent impaired oligomerization of Celia seipin leads to cell death. In heterozygous carriers, wt seipin might prevent the damage caused by mutant seipin through its sequestration into harmless mixed oligomers. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Development and release of gamma ray induced sesame mutant ANK-S2 in Sri Lanka

    International Nuclear Information System (INIS)

    Pathirane, R.; Weerasena, L.A; Bandara, P.

    2000-01-01

    Epiphytotic conditions and non-availability of resistant germplasm prompted the use of mutation induction technique to develop a variety resistant to phytophthora blight caused by Phytophthora nicotianae var. parasitica in sesame (Sesamum indicum L.). Dry seeds of three varieties were irradiated with six doses of Co-60 gamma rays in the range 100-700 Gy. The mutant line 182/3 of variety MI 3 selected from 200 Gy dose treatment in the M2 showed tolerance to the disease at Angunakolapelessa in the disease nursery. The mutant line was tested in the advanced yield trial, National Co-ordinated Varietal Trials and in the National Coordinated Varietal Adaptability Trials. It was superior to MI 3 in yield and plant survival during the seasons favouring development of the disease and was similar to MI 3 and other recommended varieties during the other seasons. the variety has cream coloured seeds, branched stem, The mutant was released as ANK S2 in 1993 and may be used to increase the declining sesame area due to low yield of existing varieties and their susceptibility to disease. It should also serve as valuable parent material in cross-breeding programmes

  1. Gender similarities and differences.

    Science.gov (United States)

    Hyde, Janet Shibley

    2014-01-01

    Whether men and women are fundamentally different or similar has been debated for more than a century. This review summarizes major theories designed to explain gender differences: evolutionary theories, cognitive social learning theory, sociocultural theory, and expectancy-value theory. The gender similarities hypothesis raises the possibility of theorizing gender similarities. Statistical methods for the analysis of gender differences and similarities are reviewed, including effect sizes, meta-analysis, taxometric analysis, and equivalence testing. Then, relying mainly on evidence from meta-analyses, gender differences are reviewed in cognitive performance (e.g., math performance), personality and social behaviors (e.g., temperament, emotions, aggression, and leadership), and psychological well-being. The evidence on gender differences in variance is summarized. The final sections explore applications of intersectionality and directions for future research.

  2. Protein expression profiling of the drosophila fragile X mutant brain reveals up-regulation of monoamine synthesis.

    Science.gov (United States)

    Zhang, Yong Q; Friedman, David B; Wang, Zhe; Woodruff, Elvin; Pan, Luyuan; O'donnell, Janis; Broadie, Kendal

    2005-03-01

    Fragile X syndrome is the most common form of inherited mental retardation, associated with both cognitive and behavioral anomalies. The disease is caused by silencing of the fragile X mental retardation 1 (fmr1) gene, which encodes the mRNA-binding, translational regulator FMRP. Previously we established a disease model through mutation of Drosophila fmr1 (dfmr1) and showed that loss of dFMRP causes defects in neuronal structure, function, and behavioral output similar to the human disease state. To uncover molecular targets of dFMRP in the brain, we use here a proteomic approach involving two-dimensional difference gel electrophoresis analyses followed by mass spectrometry identification of proteins with significantly altered expression in dfmr1 null mutants. We then focus on two misregulated enzymes, phenylalanine hydroxylase (Henna) and GTP cyclohydrolase (Punch), both of which mediate in concert the synthetic pathways of two key monoamine neuromodulators, dopamine and serotonin. Brain enzymatic assays show a nearly 2-fold elevation of Punch activity in dfmr1 null mutants. Consistently brain neurochemical assays show that both dopamine and serotonin are significantly increased in dfmr1 null mutants. At a cellular level, dfmr1 null mutant neurons display a highly significant elevation of the dense core vesicles that package these monoamine neuromodulators for secretion. Taken together, these data indicate that dFMRP normally down-regulates the monoamine pathway, which is consequently up-regulated in the mutant condition. Elevated brain levels of dopamine and serotonin provide a plausible mechanistic explanation for aspects of cognitive and behavioral deficits in human patients.

  3. Similarity or difference?

    DEFF Research Database (Denmark)

    Villadsen, Anders Ryom

    2013-01-01

    While the organizational structures and strategies of public organizations have attracted substantial research attention among public management scholars, little research has explored how these organizational core dimensions are interconnected and influenced by pressures for similarity....... In this paper I address this topic by exploring the relation between expenditure strategy isomorphism and structure isomorphism in Danish municipalities. Different literatures suggest that organizations exist in concurrent pressures for being similar to and different from other organizations in their field......-shaped relation exists between expenditure strategy isomorphism and structure isomorphism in a longitudinal quantitative study of Danish municipalities....

  4. Characterization of three Agrobacterium tumefaciens avirulent mutants with chromosomal mutations that affect induction of vir genes.

    Science.gov (United States)

    Metts, J; West, J; Doares, S H; Matthysse, A G

    1991-02-01

    Three Agrobacterium tumefaciens mutants with chromosomal mutations that affect bacterial virulence were isolated by transposon mutagenesis. Two of the mutants were avirulent on all hosts tested. The third mutant, Ivr-211, was a host range mutant which was avirulent on Bryophyllum diagremontiana, Nicotiana tabacum, N. debneyi, N. glauca, and Daucus carota but was virulent on Zinnia elegans and Lycopersicon esculentum (tomato). That the mutant phenotype was due to the transposon insertion was determined by cloning the DNA containing the transposon insertion and using the cloned DNA to replace the wild-type DNA in the parent bacterial strain by marker exchange. The transposon insertions in the three mutants mapped at three widely separated locations on the bacterial chromosome. The effects of the mutations on various steps in tumor formation were examined. All three mutants showed no alteration in binding to carrot cells. However, none of the mutants showed any induction of vir genes by acetosyringone under conditions in which the parent strain showed vir gene induction. When the mutant bacteria were examined for changes in surface components, it was found that all three of the mutants showed a similar alteration in lipopolysaccharide (LPS). LPS from the mutants was larger in size and more heavily saccharide substituted than LPS from the parent strain. Two of the mutants showed no detectable alteration in outer membrane and periplasmic space proteins. The third mutant, Ivr-225, was missing a 79-kDa surface peptide. The reason(s) for the failure of vir gene induction in these mutants and its relationship, if any, to the observed alteration in LPS are unknown.

  5. Comparing Harmonic Similarity Measures

    NARCIS (Netherlands)

    de Haas, W.B.; Robine, M.; Hanna, P.; Veltkamp, R.C.; Wiering, F.

    2010-01-01

    We present an overview of the most recent developments in polyphonic music retrieval and an experiment in which we compare two harmonic similarity measures. In contrast to earlier work, in this paper we specifically focus on the symbolic chord description as the primary musical representation and

  6. Intermediate rough Brucella abortus S19Δper mutant is DIVA enable, safe to pregnant guinea pigs and confers protection to mice.

    Science.gov (United States)

    Lalsiamthara, Jonathan; Gogia, Neha; Goswami, Tapas K; Singh, R K; Chaudhuri, Pallab

    2015-05-21

    Brucella abortus S19 is a smooth strain used as live vaccine against bovine brucellosis. Smooth lipopolysaccharide (LPS) is responsible for its residual virulence and serological interference. Rough mutants defective of LPS are more attenuated but confers lower level of protection. We describe a modified B. abortus S19 strain, named as S19Δper, which exhibits intermediate rough phenotype with residual O-polysaccharide (OPS). Deletion of perosamine synthetase gene resulted in substantial attenuation of S19Δper mutant without affecting immunogenic properties. It mounted strong immune response in Swiss albino mice and conferred protection similar to S19 vaccine. Immunized mice produced higher levels of IFN-γ, IgG2a and thus has immune response inclined towards Th1 cell mediated immunity. Sera from immunized animals did not show agglutination reaction with RBPT antigen and thus could serve as DIVA (Differentiating Infected from Vaccinated Animals) vaccine. S19Δper mutant displayed more susceptibility to serum complement mediated killing and sensitivity to polymyxin B. Pregnant guinea pigs injected with S19Δper mutant completed full term of pregnancy and did not cause abortion, still birth or birth of weak offspring. S19Δper mutant with intermediate rough phenotype displayed remarkable resemblance to S19 vaccine strain with improved properties of safety, immunogenicity and DIVA capability for control of bovine brucellosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Mutant power: using mutant allele collections for yeast functional genomics.

    Science.gov (United States)

    Norman, Kaitlyn L; Kumar, Anuj

    2016-03-01

    The budding yeast has long served as a model eukaryote for the functional genomic analysis of highly conserved signaling pathways, cellular processes and mechanisms underlying human disease. The collection of reagents available for genomics in yeast is extensive, encompassing a growing diversity of mutant collections beyond gene deletion sets in the standard wild-type S288C genetic background. We review here three main types of mutant allele collections: transposon mutagen collections, essential gene collections and overexpression libraries. Each collection provides unique and identifiable alleles that can be utilized in genome-wide, high-throughput studies. These genomic reagents are particularly informative in identifying synthetic phenotypes and functions associated with essential genes, including those modeled most effectively in complex genetic backgrounds. Several examples of genomic studies in filamentous/pseudohyphal backgrounds are provided here to illustrate this point. Additionally, the limitations of each approach are examined. Collectively, these mutant allele collections in Saccharomyces cerevisiae and the related pathogenic yeast Candida albicans promise insights toward an advanced understanding of eukaryotic molecular and cellular biology. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  8. Characterization Of Laccase T-DNA Mutants In Arabidopsis thaliana

    DEFF Research Database (Denmark)

    Andersen, Jeppe Reitan; Asp, Torben; Mansfield, Shawn

    2009-01-01

    Laccases (P-diphenol:O2 oxidoreductase; EC 1.10.3.2), also termed laccase-like multicopper oxidases, are blue copper-containing oxidases which comprise multigene families in plants. In the Arabidopsis thaliana genome, 17 laccase genes (LAC1 to LAC17) have been annotated. To identify laccases...... for LAC15 T-DNA mutant seeds and an approximate 24 hour delay in germination was observed for these seeds. An approximate 20% reduction in glucose, galactose, and xylose was observed in primary stem cell walls of the LAC2 T-DNA mutants while similar relative increases in xylose were observed for LAC8...

  9. Regioselective alkane hydroxylation with a mutant AlkB enzyme

    Science.gov (United States)

    Koch, Daniel J.; Arnold, Frances H.

    2012-11-13

    AlkB from Pseudomonas putida was engineered using in-vivo directed evolution to hydroxylate small chain alkanes. Mutant AlkB-BMO1 hydroxylates propane and butane at the terminal carbon at a rate greater than the wild-type to form 1-propanol and 1-butanol, respectively. Mutant AlkB-BMO2 similarly hydroxylates propane and butane at the terminal carbon at a rate greater than the wild-type to form 1-propanol and 1-butanol, respectively. These biocatalysts are highly active for small chain alkane substrates and their regioselectivity is retained in whole-cell biotransformations.

  10. Identification of a mutant α1 Na/K-ATPase that pumps but is defective in signal transduction.

    Science.gov (United States)

    Lai, Fangfang; Madan, Namrata; Ye, Qiqi; Duan, Qiming; Li, Zhichuan; Wang, Shaomeng; Si, Shuyi; Xie, Zijian

    2013-05-10

    It has not been possible to study the pumping and signaling functions of Na/K-ATPase independently in live cells. Both cell-free and cell-based assays indicate that the A420P mutation abolishes the Src regulatory function of Na/K-ATPase. A420P mutant has normal pumping but not signaling function. Identification of Src regulation-null mutants is crucial for addressing physiological role of Na/K-ATPase. The α1 Na/K-ATPase possesses both pumping and signaling functions. However, it has not been possible to study these functions independently in live cells. We have identified a 20-amino acid peptide (Ser-415 to Gln-434) (NaKtide) from the nucleotide binding domain of α1 Na/K-ATPase that binds and inhibits Src in vitro. The N terminus of NaKtide adapts a helical structure. In vitro kinase assays showed that replacement of residues that contain a bulky side chain in the helical structure of NaKtide by alanine abolished the inhibitory effect of the peptide on Src. Similarly, disruption of helical structure by proline replacement, either single or in combination, reduced the inhibitory potency of NaKtide on Src. To identify mutant α1 that retains normal pumping function but is defective in Src regulation, we transfected Na/K-ATPase α1 knockdown PY-17 cells with expression vectors of wild type or mutant α1 carrying Ala to Pro mutations in the region of NaKtide helical structure and generated several stable cell lines. We found that expression of either A416P or A420P or A425P mutant fully restored the α1 content and consequently the pumping capacity of cells. However, in contrast to A416P, either A420P or A425P mutant was incapable of interacting and regulating cellular Src. Consequently, expression of these two mutants caused significant inhibition of ouabain-activated signal transduction and cell growth. Thus we have identified α1 mutant that has normal pumping function but is defective in signal transduction.

  11. Analysis of Mycobacterium avium subsp. paratuberculosis mutant libraries reveals loci-dependent transcription biases and strategies to novel mutant discovery

    Science.gov (United States)

    Mycobacterium avium subsp. paratuberculosis (MAP) is the etiologic agent of Johne’s disease in ruminants and it has been implicated as a cause of Crohn’s disease in humans. The generation of comprehensive random mutant banks by transposon mutagenesis is a fundamental wide genomic technology utilized...

  12. Similar causes of various reproductive disorders in early life

    Directory of Open Access Journals (Sweden)

    Konstantin Svechnikov

    2014-02-01

    Full Text Available During the past few decades, scientific evidence has been accumulated concerning the possible adverse effects of the exposure to environmental chemicals on the well-being of wildlife and human populations. One large and growing group of such compounds of anthropogenic or natural origin is referred to as endocrine-disrupting chemicals (EDCs, due to their deleterious action on the endocrine system. This concern was first focused on the control of reproductive function particularly in males, but has later been expanded to include all possible endocrine functions. The present review describes the underlying physiology behind the cascade of developmental events that occur during sexual differentiation of males and the specific role of androgen in the masculinization process and proper organogenesis of the external male genitalia. The impact of the genetic background, environmental exposures and lifestyle factors in the etiology of hypospadias, cryptorchidism and testicular cancer are reviewed and the possible role of EDCs in the development of these reproductive disorders is discussed critically. Finally, the possible direct and programming effects of exposures in utero to widely use therapeutic compounds, environmental estrogens and other chemicals on the incidence of reproductive abnormalities and poor semen quality in humans are also highlighted.

  13. Mutant butterflies discovered at Fukushima

    International Nuclear Information System (INIS)

    Chauveau, L.

    2012-01-01

    A Japanese study has shown that malformations are more and more common in butterflies (Zizeeria maha specie) leaving near the damaged nuclear plant of Fukushima Daiichi. A population of 144 butterflies were caught in 10 villages in a radius of 200 km around Fukushima in may 2011, the ratio of malformations was 12.4%. Obvious malformations were withered antennas and wings. In september 2011 a population of 238 butterflies were caught in the same places and the ratio of malformations was then 28.1%. The increase of the malformation ratio could be explained by a cumulative effect of the radiation exposition. In a second experiment, a population of butterflies was caught in a region non-affected by the radioactive contamination and was submitted in laboratory to radiations similar to that of the contamination around Fukushima and similar malformations appeared. The conclusion of the study is that radionuclides released during the Fukushima accident have caused genetic and physiological damages to this butterfly specie. (A.C.)

  14. Determination of the catalytic activity of LEOPARD syndrome-associated SHP2 mutants toward parafibromin, a bona fide SHP2 substrate involved in Wnt signaling

    International Nuclear Information System (INIS)

    Noda, Saori; Takahashi, Atsushi; Hayashi, Takeru; Tanuma, Sei-ichi; Hatakeyama, Masanori

    2016-01-01

    SHP2, encoded by the PTPN11 gene, is a protein tyrosine phosphatase that plays a key role in the proliferation of cells via RAS-ERK activation. SHP2 also promotes Wnt signaling by dephosphorylating parafibromin. Germline missense mutations of PTPN11 are found in more than half of patients with Noonan syndrome (NS) and LEOPARD syndrome (LS), both of which are congenital developmental disorders with multiple common symptoms. However, whereas NS-associated PTPN11 mutations give rise to gain-of-function SHP2 mutants, LS-associated SHP2 mutants are reportedly loss-of-function mutants. To determine the phosphatase activity of LS-associated SHP2 more appropriately, we performed an in vitro phosphatase assay using tyrosine-phosphorylated parafibromin, a biologically relevant substrate of SHP2 and the positive regulator of Wnt signaling that is activated through SHP2-mediated dephosphorylation. We found that LS-associated SHP2 mutants (Y279C, T468M, Q506P, and Q510E) exhibited a substantially reduced phosphatase activity toward parafibromin when compared with wild-type SHP2. Furthermore, each of the LS-associated mutants displayed a differential degree of decrease in phosphatase activity. Deviation of the SHP2 catalytic activity from a certain range, either too strong or too weak, may therefore lead to similar clinical outcomes in NS and LS, possibly through an imbalanced Wnt signal caused by inadequate dephosphorylation of parafibromin. - Highlights: • LS-associated SHP2 mutants dephosphorylate parafibromin on Y290, Y293, and Y315. • LS-associated SHP2 mutants display a reduced tyrosine phosphatase activity. • LS-specific SHP2-Y279C is catalytically less active than LS-specific SHP2-T468M. • NS/LS-associated SHP2-Q506P has both hyper- and hypomorphic enzymatic properties.

  15. Determination of the catalytic activity of LEOPARD syndrome-associated SHP2 mutants toward parafibromin, a bona fide SHP2 substrate involved in Wnt signaling

    Energy Technology Data Exchange (ETDEWEB)

    Noda, Saori [Division of Microbiology, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan); Department of Biochemistry, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Chiba (Japan); Takahashi, Atsushi; Hayashi, Takeru [Division of Microbiology, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan); Tanuma, Sei-ichi [Department of Biochemistry, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Chiba (Japan); Hatakeyama, Masanori, E-mail: mhata@m.u-tokyo.ac.jp [Division of Microbiology, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan)

    2016-01-22

    SHP2, encoded by the PTPN11 gene, is a protein tyrosine phosphatase that plays a key role in the proliferation of cells via RAS-ERK activation. SHP2 also promotes Wnt signaling by dephosphorylating parafibromin. Germline missense mutations of PTPN11 are found in more than half of patients with Noonan syndrome (NS) and LEOPARD syndrome (LS), both of which are congenital developmental disorders with multiple common symptoms. However, whereas NS-associated PTPN11 mutations give rise to gain-of-function SHP2 mutants, LS-associated SHP2 mutants are reportedly loss-of-function mutants. To determine the phosphatase activity of LS-associated SHP2 more appropriately, we performed an in vitro phosphatase assay using tyrosine-phosphorylated parafibromin, a biologically relevant substrate of SHP2 and the positive regulator of Wnt signaling that is activated through SHP2-mediated dephosphorylation. We found that LS-associated SHP2 mutants (Y279C, T468M, Q506P, and Q510E) exhibited a substantially reduced phosphatase activity toward parafibromin when compared with wild-type SHP2. Furthermore, each of the LS-associated mutants displayed a differential degree of decrease in phosphatase activity. Deviation of the SHP2 catalytic activity from a certain range, either too strong or too weak, may therefore lead to similar clinical outcomes in NS and LS, possibly through an imbalanced Wnt signal caused by inadequate dephosphorylation of parafibromin. - Highlights: • LS-associated SHP2 mutants dephosphorylate parafibromin on Y290, Y293, and Y315. • LS-associated SHP2 mutants display a reduced tyrosine phosphatase activity. • LS-specific SHP2-Y279C is catalytically less active than LS-specific SHP2-T468M. • NS/LS-associated SHP2-Q506P has both hyper- and hypomorphic enzymatic properties.

  16. Identical substitutions in magnesium chelatase paralogs result in chlorophyll deficient soybean mutants

    Science.gov (United States)

    The soybean (Glycine max (L.) Merr.) chlorophyll deficient line MinnGold is a spontaneous mutant characterized by yellow foliage. Map-based cloning and transgenic complementation revealed that the mutant phenotype is caused by a non-synonymous nucleotide substitution in the third exon of a Mg-chelat...

  17. Alterations in biochemical and physiological characters in radiation-induced mutants of grain legumes

    International Nuclear Information System (INIS)

    Mueller, H.P.

    1984-01-01

    Selected examples from different grain legumes are studied. The biochemically and physiologically detectable alterations in distintc characters as caused by the action of mutant genes are presented comparatively. The interactions between different mutant genes in order to evaluated the influence of the genotypic constitution on the expression of mutated genes are emphasized. (M.A.C.) [pt

  18. Root and Nodulation Phenotypes of the Ethylene-Insensitive Sickle Mutant of Medicago truncatula

    Directory of Open Access Journals (Sweden)

    JOKO PRAYITNO

    2010-09-01

    Full Text Available The sickle (skl mutant of the model legume Medicago truncatula is an ethylene-sensitive mutant that have a ten-fold increase in nodule numbers. The nodulation and root phenotypes of the skl mutant were investigated and further characterised. The skl mutant had longer roots than the wild type, but when inoculated with Sinorhizobium, its root length was reduced to the level of wild type. Furthermore, lateral root numbers in uninoculated skl were similar to those in uninoculated wild type. However, when the root tips were decapitated, fewer lateral roots formed in skl than in wild type. Nodule numbers of the skl mutant were significantly reduced by low nitrate concentration (2.5 mM. These results suggest that skl mutant has alterations in both root and nodule development.

  19. Collection of rice mutants and application studies of their agronomic characters

    International Nuclear Information System (INIS)

    Sun Shuxiang; Jin Wei; Luo Qian; Sheng Ping; Huang Rongmin

    1993-01-01

    More than 1600 accessions of rice mutant germplasm have been collected since 1980, and 1142 accessions of mutants have been identified according to their agronomy and pattern characters. A part of mutants were compared with their original cultivars in eight main agronomic characters. The results showed that the agronomic characters of mutants induced by ionizing radiations changed to both positive and negative directions compared with their original cultivars. Only 6.3% mutants varied in single agronomic character, and 91.1% mutants varied in two to six agronomic characters. Tenetic analysis and Cellular observations were carried out for two kinds of early mutants. It showed that early mutants 'Yuan Feng Zao' are controlled by two independent and incomplete dominant genes. For the dwarf, the reduction of the number of longitudinal cell layers causes the stem shorter and the increase of the number of horizontal cell layers causes the stem wall thicker. More than 100 preserved accessions of mutants were supplied to breeding units as parents or for genetic studies. Sixteen cultivars (lines) were bred from the parents which played an important role in raising the output of rice production

  20. Histological and genetic studies on the male sterile mutants of tomato induced by gamma radiation and chemical mutagens

    Energy Technology Data Exchange (ETDEWEB)

    Choi, J K [Office of Rural Development, Suwon (Republic of Korea) Horticultural Experiment Station

    1976-03-01

    The object of this experiment was to test the radiosensitivity of the M/sub 1/ generation, and to determine the inheritance and morphological characteristics of the male-sterile mutants in tomatoes. The results obtained are as follows: Radiation damage varied with the water content of the seeds. The least damage occurred in the range of 11.34 to 14.29 percent moisture. Four tomato cultivars were gamma irradiated. The cultivar Sekai-ichi was the most sensitive while the other responded similarly to each other. Chemical mutagen treatments caused greater damage to germination, to delayed flowering and to pollen fertility than did radiation. Pollen fertility and seeds per fruit in seedling gamma irradiated plants decreased as the dosage and dose rate increased. Five male-sterile mutants were found. Each was controlled by a single recessive gene. All five male-steriles were nonallelic. Floral sized of the male-sterile mutants were slightly smaller. Ovule fertility varied, usually being lower than normal type. Male sterility varied, usually being lower than normal type. Male sterility in 109-1ms strain was caused by unbalanced, insufficient nutrients being made available to the pollen-mother cells from the tapetal tissued. (author).

  1. Gain and loss of function of ALS-related mutations of TARDBP (TDP-43) cause motor deficits in vivo.

    Science.gov (United States)

    Kabashi, Edor; Lin, Li; Tradewell, Miranda L; Dion, Patrick A; Bercier, Valérie; Bourgouin, Patrick; Rochefort, Daniel; Bel Hadj, Samar; Durham, Heather D; Vande Velde, Christine; Rouleau, Guy A; Drapeau, Pierre

    2010-02-15

    TDP-43 has been found in inclusion bodies of multiple neurological disorders, including amyotrophic lateral sclerosis, frontotemporal dementia, Parkinson's disease and Alzheimer's disease. Mutations in the TDP-43 encoding gene, TARDBP, have been subsequently reported in sporadic and familial ALS patients. In order to investigate the pathogenic nature of these mutants, the effects of three consistently reported TARDBP mutations (A315T, G348C and A382T) were tested in cell lines, primary cultured motor neurons and living zebrafish embryos. Each of the three mutants and wild-type (WT) human TDP-43 localized to nuclei when expressed in COS1 and Neuro2A cells by transient transfection. However, when expressed in motor neurons from dissociated spinal cord cultures these mutant TARDBP alleles, but less so for WT TARDBP, were neurotoxic, concomitant with perinuclear localization and aggregation of TDP-43. Finally, overexpression of mutant, but less so of WT, human TARDBP caused a motor phenotype in zebrafish (Danio rerio) embryos consisting of shorter motor neuronal axons, premature and excessive branching as well as swimming deficits. Interestingly, knock-down of zebrafisfh tardbp led to a similar phenotype, which was rescued by co-expressing WT but not mutant human TARDBP. Together these approaches showed that TARDBP mutations cause motor neuron defects and toxicity, suggesting that both a toxic gain of function as well as a novel loss of function may be involved in the molecular mechanism by which mutant TDP-43 contributes to disease pathogenesis.

  2. Development Of New Chrysanthemum Mutants For Malaysian Floriculture Industry

    International Nuclear Information System (INIS)

    Zaiton Ahmad; Affrida Abu Hassan; Shakinah Salleh; Nurul Hidayah Mahmud; Shuhaimi Shamsudin; Mohamed Najli Mohamed Yasin

    2014-01-01

    This five-year project was in collaboration with Japan Atomic Energy Agency (JAEA) under the Bilateral Cooperative Research Program and was partly funded by Ministry of Agriculture and Agro-Based Industry (MOA) under Agriculture R&D Fund. The main objective was to produce new chrysanthemum varieties with good horticultural traits especially for cut flower production. In this project, tissue culture samples of chrysanthemum (red and pink varieties) were sent to JAEA for ion beam irradiations. Plant regeneration and multiplication were carried out at Nuclear Malaysia whilst field screenings for morphological characteristics were done at MARDI Cameron Highlands. Through this project, a number of stable chrysanthemum mutants with various new features have been generated and of these, 8 mutants were selected based on their uniqueness and/or suitability for cut flower production. In preparation for future commercialization process, five of these mutants have been filed for plant variety protection with Department of Agriculture Malaysia and a similar process in Japan is also under consideration. In addition, molecular marker work to fingerprint these mutants has also been initiated and future research may also include development of markers for selected horticultural traits and isolation of unique mutant genes. (author)

  3. An extra early mutant of pigeonpea

    International Nuclear Information System (INIS)

    Ravikesavan, R.; Kalaimagal, T.; Rathnaswamy, R.

    2001-01-01

    The redgram (Cajanus cajan (L.) Huth) variety 'Prabhat DT' was gamma irradiated with 100, 200, 300 and 400 Gy doses. Several mutants have been identified viz., extra early mutants, monostem mutants, obcordifoliate mutants and bi-stigmatic mutants. The extra early mutant was obtained when treated with 100 Gy dose. The mutant was selfed and forwarded from M 2 to M 4 generation. In the M 4 generation the mutant line was raised along with the parental variety. Normal cultural practices were followed and the biometrical observations were recorded. It was observed that for the characters viz., total number of branches per plant, number of pods per plants, seeds per pod, 100 seed weight and seed yield per plant there was no difference between the mutant and parent variety. Whereas, regarding the days to flowering and maturity the mutants were earlier than the parents. The observation was recorded from two hundred plants each. The mutant gives the same yield in 90 days as that of the parent variety in 107 days, which make it an economic mutant

  4. Problem-Solving Test: Tryptophan Operon Mutants

    Science.gov (United States)

    Szeberenyi, Jozsef

    2010-01-01

    This paper presents a problem-solving test that deals with the regulation of the "trp" operon of "Escherichia coli." Two mutants of this operon are described: in mutant A, the operator region of the operon carries a point mutation so that it is unable to carry out its function; mutant B expresses a "trp" repressor protein unable to bind…

  5. Purkinje Cell Compartmentation in the Cerebellum of the Lysosomal Acid Phosphatase 2 Mutant Mouse (Nax - Naked-Ataxia Mutant Mouse)

    Science.gov (United States)

    Bailey, Karen; Rahimi Balaei, Maryam; Mannan, Ashraf; Del Bigio, Marc R.; Marzban, Hassan

    2014-01-01

    The Acp2 gene encodes the beta subunit of lysosomal acid phosphatase, which is an isoenzyme that hydrolyzes orthophosphoric monoesters. In mice, a spontaneous mutation in Acp2 results in severe cerebellar defects. These include a reduced size, abnormal lobulation, and an apparent anterior cerebellar disorder with an absent or hypoplastic vermis. Based on differential gene expression in the cerebellum, the mouse cerebellar cortex can normally be compartmentalized anteroposteriorly into four transverse zones and mediolaterally into parasagittal stripes. In this study, immunohistochemistry was performed using various Purkinje cell compartmentation markers to examine their expression patterns in the Acp2 mutant. Despite the abnormal lobulation and anterior cerebellar defects, zebrin II and PLCβ4 showed similar expression patterns in the nax mutant and wild type cerebellum. However, fewer stripes were found in the anterior zone of the nax mutant, which could be due to a lack of Purkinje cells or altered expression of the stripe markers. HSP25 expression was uniform in the central zone of the nax mutant cerebellum at around postnatal day (P) 18–19, suggesting that HSP25 immunonegative Purkinje cells are absent or delayed in stripe pattern expression compared to the wild type. HSP25 expression became heterogeneous around P22–23, with twice the number of parasagittal stripes in the nax mutant compared to the wild type. Aside from reduced size and cortical disorganization, both the posterior zone and nodular zone in the nax mutant appeared less abnormal than the rest of the cerebellum. From these results, it is evident that the anterior zone of the nax mutant cerebellum is the most severely affected, and this extends beyond the primary fissure into the rostral central zone/vermis. This suggests that ACP2 has critical roles in the development of the anterior cerebellum and it may regulate anterior and central zone compartmentation. PMID:24722417

  6. Evidence for dynamic network regulation of Drosophila photoreceptor function from mutants lacking the neurotransmitter histamine

    Directory of Open Access Journals (Sweden)

    An eDau

    2016-03-01

    Full Text Available Synaptic feedback from interneurons to photoreceptors can help to optimize visual information flow by balancing its allocation on retinal pathways under changing light conditions. But little is known about how this critical network operation is regulated dynamically. Here, we investigate this question by comparing signaling properties and performance of wild-type Drosophila R1-R6 photoreceptors to those of the hdcJK910 mutant, which lacks the neurotransmitter histamine and therefore cannot transmit information to interneurons. Recordings show that hdcJK910 photoreceptors sample similar amounts of information from naturalistic stimulation to wild-type photoreceptors, but this information is packaged in smaller responses, especially under bright illumination. Analyses reveal how these altered dynamics primarily resulted from network overload that affected hdcJK910 photoreceptors in two ways. First, the missing inhibitory histamine input to interneurons almost certainly depolarized them irrevocably, which in turn increased their excitatory feedback to hdcJK910 R1-R6s. This tonic excitation depolarized the photoreceptors to artificially high potentials, reducing their operational range. Second, rescuing histamine input to interneurons in hdcJK910 mutant also restored their normal phasic feedback modulation to R1-R6s, causing photoreceptor output to accentuate dynamic intensity differences at bright illumination, similar to the wild-type. These results provide mechanistic explanations of how synaptic feedback connections optimize information packaging in photoreceptor output and novel insight into the operation and design of dynamic network regulation of sensory neurons.

  7. Normal aging modulates the neurotoxicity of mutant huntingtin.

    Directory of Open Access Journals (Sweden)

    Elsa Diguet

    Full Text Available Aging likely plays a role in neurodegenerative disorders. In Huntington's disease (HD, a disorder caused by an abnormal expansion of a polyglutamine tract in the protein huntingtin (Htt, the role of aging is unclear. For a given tract length, the probability of disease onset increases with age. There are mainly two hypotheses that could explain adult onset in HD: Either mutant Htt progressively produces cumulative defects over time or "normal" aging renders neurons more vulnerable to mutant Htt toxicity. In the present study, we directly explored whether aging affected the toxicity of mutant Htt in vivo. We studied the impact of aging on the effects produced by overexpression of an N-terminal fragment of mutant Htt, of wild-type Htt or of a beta-Galactosidase (beta-Gal reporter gene in the rat striatum. Stereotaxic injections of lentiviral vectors were performed simultaneously in young (3 week and old (15 month rats. Histological evaluation at different time points after infection demonstrated that the expression of mutant Htt led to pathological changes that were more severe in old rats, including an increase in the number of small Htt-containing aggregates in the neuropil, a greater loss of DARPP-32 immunoreactivity and striatal neurons as assessed by unbiased stereological counts.The present results support the hypothesis that "normal" aging is involved in HD pathogenesis, and suggest that age-related cellular defects might constitute potential therapeutic targets for HD.

  8. Results of the use of induced mutants in maize breeding

    International Nuclear Information System (INIS)

    Balint, A.; Kovacs, Gezane; Hajos, Laszlone; Geczki, I.

    1979-01-01

    The investigated mutagens have the same effect on the increasing of protein content. In the case of WF9 mutants no essential improvement can be found compared with the untreated co trol selected for protein. ''Lines'' flowering 16-19 days earlier than controls were produced; the most effective agent of this production is the fast neutron. Mutation caused a significant change in their combining ability, but there were more negative variants than positive ones. Three hybrids with stronger stalk than that of MvSc 620 were obtained. Stalk standing ability of mutants did not improve. The flowering date of lines (male) is in r=+0.5672 +++ correlation to the yield of their test hybrid. Mutant lines in SC test cross seemed to be stable. The correlation of the yield of two years is r=+0.8659. The correlation of both the yield of test hybrids to the protein content of mutant lines (r=0.2307) and the flowering date of lines to their protein content (r=-0.3032) is loose. The earliest mutant line of WF9, which produced low crop (5000 kg/ha) when crossed with N6, gave a high-yielding hybrid when crossed with other lines. The average yield of eight combinations was 10050 kg/ha and the highest yield was 11680 kg/ha. (author)

  9. Zebrafish bandoneon mutants display behavioral defects due to a mutation in the glycine receptor β-subunit

    Science.gov (United States)

    Hirata, Hiromi; Saint-Amant, Louis; Downes, Gerald B.; Cui, Wilson W.; Zhou, Weibin; Granato, Michael; Kuwada, John Y.

    2005-01-01

    Bilateral alternation of muscle contractions requires reciprocal inhibition between the two sides of the hindbrain and spinal cord, and disruption of this inhibition should lead to simultaneous activation of bilateral muscles. At 1 day after fertilization, wild-type zebrafish respond to mechanosensory stimulation with multiple fast alternating trunk contractions, whereas bandoneon (beo) mutants contract trunk muscles on both sides simultaneously. Similar simultaneous contractions are observed in wild-type embryos treated with strychnine, a blocker of the inhibitory glycine receptor (GlyR). This result suggests that glycinergic synaptic transmission is defective in beo mutants. Muscle voltage recordings confirmed that muscles on both sides of the trunk in beo are likely to receive simultaneous synaptic input from the CNS. Recordings from motor neurons revealed that glycinergic synaptic transmission was missing in beo mutants. Furthermore, immunostaining with an antibody against GlyR showed clusters in wild-type neurons but not in beo neurons. These data suggest that the failure of GlyRs to aggregate at synaptic sites causes impairment of glycinergic transmission and abnormal behavior in beo mutants. Indeed, mutations in the GlyR β-subunit, which are thought to be required for proper localization of GlyRs, were identified as the basis for the beo mutation. These data demonstrate that GlyRβ is essential for physiologically relevant clustering of GlyRs in vivo. Because GlyR mutations in humans lead to hyperekplexia, a motor disorder characterized by startle responses, the zebrafish beo mutant should be a useful animal model for this condition. PMID:15928085

  10. Dwarf mutant of rice variety Seratus Malam

    International Nuclear Information System (INIS)

    Mugiono, P. S.; Soemanggono, A.M.R.

    1989-01-01

    Full text: Seeds of 'Seratus Malam', a local tall upland variety with long panicles and high yield potential were irradiated with 10-50 krad gamma rays in 1983. From 50,000 M 2 plants, 130 semidwarf mutants and 1 dwarf mutant were selected. The dwarf mutant M-362 was obtained from the 10 krad treatment. The mutant shows about 50% reduction in plant height, but also in number of productive tillers. Thus the yield per plant is also significantly less. However, the mutant gene is not allelic to DGWG and therefore may be useful in cross breeding. (author)

  11. Bending patterns of chlamydomonas flagella: III. A radial spoke head deficient mutant and a central pair deficient mutant.

    Science.gov (United States)

    Brokaw, C J; Luck, D J

    1985-01-01

    Flash photomicrography at frequencies up to 300 Hz and computer-assisted image analysis have been used to obtain parameters describing the flagellar bending patterns of mutants of Chlamydomonas reinhardtii. All strains contained the uni1 mutation, to facilitate photography. The radial spoke head deficient mutant pf17, and the central pair deficient mutant, pf15, in combination with suppressor mutations that restore motility without restoring the ultrastructural or biochemical deficiencies, both generate forward mode bending patterns with increased shear amplitude and decreased asymmetry relative to the "wild-type" uni1 flagella described previously. In the reverse beating mode, the suppressed pf17 mutants generate reverse bending patterns with large shear amplitudes. Reverse beating of the suppressed pf15 mutants is rare. There is a reciprocal relationship between increased shear amplitude and decreased beat frequency, so that the velocity of sliding between flagellar microtubules is not increased by an increase in shear amplitude. The suppressor mutations alone cause decreased frequency and sliding velocity in both forward and reverse mode beating, with little change in shear amplitude or symmetry.

  12. Similar or different?

    DEFF Research Database (Denmark)

    Cornér, Solveig; Pyhältö, Kirsi; Peltonen, Jouni

    2018-01-01

    Previous research has identified researcher community and supervisory support as key determinants of the doctoral journey contributing to students’ persistence and robustness. However, we still know little about cross-cultural variation in the researcher community and supervisory support experien...... counter partners, whereas the Finnish students perceived lower levels of instrumental support than the Danish students. The findings imply that seemingly similar contexts hold valid differences in experienced social support and educational strategies at the PhD level....... experienced by PhD students within the same discipline. This study explores the support experiences of 381 PhD students within the humanities and social sciences from three research-intensive universities in Denmark (n=145) and Finland (n=236). The mixed methods design was utilized. The data were collected...... counter partners. The results also indicated that the only form of support in which the students expressed more matched support than mismatched support was informational support. Further investigation showed that the Danish students reported a high level of mismatch in emotional support than their Finnish...

  13. Repair-defective mutants of Alteromonas espejiana, the host for bacteriophage PM2

    International Nuclear Information System (INIS)

    Zerler, B.R.; Wallace, S.S.

    1984-01-01

    The in vivo repair processes of Alteromonas espejiana, the host for bacteriophage PM2, were characterized, and UV- and methyl methanesulfonate (MMS)-sensitive mutants were isolated. Wild-type A. espejiana cells were capable of photoreactivation, excision, recombination, and inducible repair. There was no detecttable pyrimidine dimer-DNA N-glycosylase activity, and pyrimidine dimer removal appeared to occur by a pathway analogous to the Escherichia coli Uvr pathway. The UV- and MMS-sensitive mutants of A. espejiana included three groups, each containing at least one mutation involved with excision, recombination, or inducible repair. One group that was UV sensitive but not sensitive to MMS or X rays showed a decreased ability to excise pyrimidine dimers. Mutants in this group were also sensitive to psoralen plus near-UV light and were phenotypically analogous to the E. coli uvr mutants. A second group was UV and MMS sensitive but not sensitive to X rays and appeared to contain mutations in a gene(s) involved in recombination repair. These recombination-deficient mutants differed from the E. coli rec mutants, which are MMS and X-ray sensitive. The third group of A. espejiana mutants was sensitive to UV, MMS, and X rays. These mutants were recombination deficient, lacked inducible repair, and were phenotypically similar to E. coli recA mutants

  14. An early maturing rice mutant released as a variety

    International Nuclear Information System (INIS)

    Azam, M.A.; Imtiaz Uddin, Md.

    2001-01-01

    In the content of food grain production deficiency (about 1.0-1.5 million tons of rice per year according to the Bangladesh Bureau of Statistics, 1998) an induced mutation programme was undertaken in 1985. One moderate early maturing and high yielding rice mutant line (BINA6-84-4-115) has been developed by irradiating F 2 seeds of the cross 'BR4' x 'Iratom 38'. Three treatments viz., 250, 300 and 350 Gy were given to the F 2 seeds. Finally, this line was selected in M 6 generation for advanced yield trial. The line was evaluated in comparative trials with another mutant line BINA6-84-4-163. These two mutant lines had been selected earlier from 300 Gy originated lines. The two check varieties, 'BR 11' and 'BR 22' were also included in the trial, which was conducted in two consecutive T. aman seasons (July to December) during 1994 and 1995 at five locations in Bangladesh. From the results, it was evident that the mutant BINA6-84-4-115 did not differ much with the other mutant lines or check varieties in respect to plant height, number of effective tillers and panicle length but it was 10-18 days earlier than the other 3 entries. It produced a similar yield as the check BR 11 in 1994 and a higher yield than the check BR 11 and BR 22 in 1995. This mutant line gave the highest yield per day among all the entries. In addition to this, the grains are long, fine and possess a high L/B ratio, which are of high commercial value. This line has been released by the National Seed Board of Bangladesh in 1998 as a commercial variety under the name 'BINADHAN-4' for cultivation throughout Bangladesh

  15. Gamma ray induced mutants in Coleus

    International Nuclear Information System (INIS)

    Vasudevan, K.; Jos, J.S.

    1988-01-01

    The germplasm collection of Chinese potato (Coleus parviflorus Benth) contains almost no variation for yield contributing traits. The crop does not produce seeds. Treatment of underground tubers with 1 kR, 2 kR, 3 kR and 4 kR gamma rays resulted in 50 morphologically different mutants which are maintained as mutant clones. In the M 1 V 1 generation, suspected mutant sprouts, were carefully removed and grown separately. The most interesting mutant types are the following: (i) erect mutant with spoon shaped light green leaves, 30 cm long inflorescences against 20 cm in the control, cylindrical tubers measuring ca. 7.0 cm long and 3 cm girth against 4 cm and 2.5 cm in the control (ii) early mutants 1 and 2, one having less leaf serration, the other having light green small leaves and dwarf type (iii) fleshy leaf mutant, dark green, thick and smooth leaves. Control plants spread almost in 1 m 2 area and bear tubers from the nodes of branches. In the early mutants tuber formation is mainly restricted to the base of the plant, which makes harvest easier. The crop usually matures within 150 - 160 days, the early mutants are ready for harvest 100 days after planting. As the mutants are less spreading, the yield could be increased by closer spacing

  16. Gamma ray induced mutants in Coleus

    Energy Technology Data Exchange (ETDEWEB)

    Vasudevan, K; Jos, J S [Central Tuber Crops Research Institute, Trivandrum, Kerala (India)

    1988-07-01

    The germplasm collection of Chinese potato (Coleus parviflorus Benth) contains almost no variation for yield contributing traits. The crop does not produce seeds. Treatment of underground tubers with 1 kR, 2 kR, 3 kR and 4 kR gamma rays resulted in 50 morphologically different mutants which are maintained as mutant clones. In the M{sub 1}V{sub 1} generation, suspected mutant sprouts, were carefully removed and grown separately. The most interesting mutant types are the following: (i) erect mutant with spoon shaped light green leaves, 30 cm long inflorescences against 20 cm in the control, cylindrical tubers measuring ca. 7.0 cm long and 3 cm girth against 4 cm and 2.5 cm in the control (ii) early mutants 1 and 2, one having less leaf serration, the other having light green small leaves and dwarf type (iii) fleshy leaf mutant, dark green, thick and smooth leaves. Control plants spread almost in 1 m{sup 2} area and bear tubers from the nodes of branches. In the early mutants tuber formation is mainly restricted to the base of the plant, which makes harvest easier. The crop usually matures within 150 - 160 days, the early mutants are ready for harvest 100 days after planting. As the mutants are less spreading, the yield could be increased by closer spacing.

  17. Chlorophyll mutation in field Pea (Pisum Sativum L.) that causes white stem in plants

    International Nuclear Information System (INIS)

    Naidenova, N.; Vassilevska-Ivanova, R.

    2006-01-01

    A white stem pea mutant recovered after exposing seeds of P. sativum cv Auralia to gamma-irradiation. The mutant has shown to have single-gene recessive inheritance, characterized morphologically and for seed productivity. New mutant 1/240 had similar phenotype to previously named mutants white stem and alts (albina-terminalis) but no allelism tests were performed between the new and the previously reported mutants. The mutation in line 1/240 may be useful as a genetic marker. (authors)

  18. EMS mutant spectra generated by multi-parameter flow cytometry

    Energy Technology Data Exchange (ETDEWEB)

    Keysar, Stephen B. [Cell and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO (United States); Fox, Michael H., E-mail: michael.fox@colostate.edu [Cell and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO (United States); Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO (United States)

    2009-12-01

    The CHO A{sub L} cell line contains a single copy of human chromosome 11 that encodes several cell surface proteins including glycosyl phosphatidylinositol (GPI) linked CD59 and CD90, as well as CD98, CD44 and CD151 which are not GPI-linked. The flow cytometry mutation assay (FCMA) measures mutations of the CD59 gene by the absence of fluorescence when stained with antibodies against the CD59 cell surface protein. We have measured simultaneous mutations in CD59, CD44, CD90, CD98 and CD151 to generate a mutant spectrum for ionizing radiation. After treatment with ethyl methanesulfonate (EMS) many cells have an intermediate level of CD59 staining. Single cells were sorted from CD59{sup -} regions with varying levels of fluorescence and the resulting clonal populations had a stable phenotype for CD59 expression. Mutant spectra were generated by flow cytometry using the isolated clones and nearly all clones were mutated in CD59 only. Interestingly, about 60% of the CD59 negative clones were actually GPI mutants determined by staining with the GPI specific fluorescently labeled bacterial toxin aerolysin (FLAER). The GPI negative cells are most likely caused by mutations in the X-linked pigA gene important in GPI biosynthesis. Small mutations of pigA and CD59 were expected for the alkylating agent EMS and the resulting spectra are significantly different than the large deletions found when analyzing radiation mutants. After analyzing the CD59{sup -} clonal populations we have adjusted the FCMA mutant regions from 1% to 10% of the mean of the CD59 positive peak to include the majority of CD59 mutants.

  19. Nanoformulated cell-penetrating survivin mutant and its dual actions

    Directory of Open Access Journals (Sweden)

    Sriramoju B

    2014-07-01

    Full Text Available Bhasker Sriramoju, Rupinder K Kanwar, Jagat R Kanwar Nanomedicine Laboratory of Immunology and Molecular Biomedical Research (NLIMBR, School of Medicine, Faculty of Health, Deakin University, Geelong, Australia Abstract: In this study, we investigated the differential actions of a dominant-negative survivin mutant (SurR9-C84A against cancerous SK-N-SH neuroblastoma cell lines and differentiated SK-N-SH neurons. In both the cases, the mutant protein displayed dual actions, where its effects were cytotoxic toward cancerous cells and proliferative toward the differentiated neurons. This can be explained by the fact that tumorous (undifferentiated SK-N-SH cells have a high endogenous survivin pool and upon treatment with mutant SuR9-C84A causes forceful survivin expression. These events significantly lowered the microtubule dynamics and stability, eventually leading to apoptosis. In the case of differentiated SK-N-SH neurons that express negligible levels of wild-type survivin, the mutant indistinguishably behaved in a wild-type fashion. It also favored cell-cycle progression, forming the chromosome-passenger complex, and stabilized the microtubule-organizing center. Therefore, mutant SurR9-C84A represents a novel therapeutic with its dual actions (cytotoxic toward tumor cells and protective and proliferative toward neuronal cells, and hence finds potential applications against a variety of neurological disorders. In this study, we also developed a novel poly(lactic-co-glycolic acid nanoparticulate formulation to surmount the hurdles associated with the delivery of SurR9-C84A, thus enhancing its effective therapeutic outcome. Keywords: survivin mutant, neurological disorders, protein therapeutics, inhibitor of apoptosis protein family, poly(lactic-co-glycolic acid

  20. Sharing mutants and experimental information prepublication using FgMutantDb (https://scabusa.org/FgMutantDb).

    Science.gov (United States)

    Baldwin, Thomas T; Basenko, Evelina; Harb, Omar; Brown, Neil A; Urban, Martin; Hammond-Kosack, Kim E; Bregitzer, Phil P

    2018-06-01

    There is no comprehensive storage for generated mutants of Fusarium graminearum or data associated with these mutants. Instead, researchers relied on several independent and non-integrated databases. FgMutantDb was designed as a simple spreadsheet that is accessible globally on the web that will function as a centralized source of information on F. graminearum mutants. FgMutantDb aids in the maintenance and sharing of mutants within a research community. It will serve also as a platform for disseminating prepublication results as well as negative results that often go unreported. Additionally, the highly curated information on mutants in FgMutantDb will be shared with other databases (FungiDB, Ensembl, PhytoPath, and PHI-base) through updating reports. Here we describe the creation and potential usefulness of FgMutantDb to the F. graminearum research community, and provide a tutorial on its use. This type of database could be easily emulated for other fungal species. Published by Elsevier Inc.

  1. Identification of some Rice Mutants using Morphological and Molecular Methods

    International Nuclear Information System (INIS)

    Sobieh, S.E.S.

    2006-01-01

    This investigation was conducted at the experimental farm of plant research department, nuclear research center, atomic energy authority, abu zaabal in order to verify four rice genotypes i.e sakha 102, giza 178, high yielding mutant (Ms 6) and high yielding mutant (MG 16). the (UPOV) rice descriptor was used to identify the germplasm morphologically .Molecular RAPD-PCR was used to identify genetic variability on the molecular level for the tested genotypes. 1- the results indicated that according to (UPOV) rice descriptor eight morphological traits were completely different between mutant Ms 6 in comparison with the parent sakha 102 and mut. MG 16 in comparison parent giza 178, the traits were ; stem thickness, stem length, panicle length, 1000-grain weight, grain length, grain width decorticated grain length and decorticated grain width. 2- using 10 arbitrary primers, through four rice genotypes on the molecular level using RAPD markers. the size of the amplified fragments were ranged from 0.201 to 2.036 k bp. two primers OPB-13 and OPB-16 showed no polymorphism among genotypes tested. 3- the total number of amplicons produced by the 8 polymorphic RAPD profiels was 66. the total number of monomorphic amplicons was 32. however, the total number of polymorphic amplicons was 34. 4- the percentage of polymorphism ranged from (22.22%) for primer OPA-18 to (90%) for primer OPB-11. 5-the highest genetic similarity (90.3%) was between sakha 102 and high yielding mut. (Ms 6). the genetic similarity (75.5%) was between giza 178 and high yielding mut.(MG 16). 6- one positive unique marker amplified by OPA-18 Primer identified the high yielding mutant Ms 6 but three positive unique markers amplified by OPB-17 primer and OPA-18 primer identified the high yielding mutant MG 16

  2. Gamma rays induced bold seeded high yielding mutant in chickpea

    International Nuclear Information System (INIS)

    Wani, A.A.; Anis, M.

    2001-01-01

    In pulses especially in chickpea (Cicer arietinum L.), genetic variability has been exhausted due to natural selection and hence conventional breeding methods are not very fruitful. Mutation techniques are the best methods to enlarge the genetically conditioned variability of a species within a short time and have played a significant role in the development of many crop varieties. Investigations on the effects of ionizing radiations and chemical mutagens in induction of macro-mutations have received much attention owing to their utmost importance in plant breeding. The present study reports a bold seeded mutant in chickpea, the most dominating pulse crop on the Indian subcontinent. Fresh seeds of chickpea variety 'Pusa-212' were procured from IARI, New Delhi and treated with different doses/concentrations of gamma rays ( 60 Co source at NBRI, Lucknow) and ethyl methanesulphonate (EMS), individually as well as in combination, to raise the M1 generation. Seeds of M 1 plants were sown to raise M2 plant progenies. A bold seeded mutant was isolated from 400 Gy gamma ray treatments. The mutant was confirmed as true bred, all the mutant seeds gave rise to morphologically similar plants in M 3 , which were quite distinct from the control. The bold seeded mutant showed 'gigas' characteristics and vigorous growth. The plant remained initially straight but later on attained a trailing habit due to heavy secondary branching. The leaves, petioles, flowers, pods and seeds were almost double that of the parent variety, in size. The flowering occurred 10 days later than the parent and maturity was also delayed accordingly. Observations were recorded on various quantitative traits. Plant height and number of primary branches showed a significant improvement over the parent. It is interesting to note that the number of pods and number of seeds per pod significantly decreased. However, the hundred seed weight (31.73±0.59g) in the mutant plants was more than double in the parent

  3. The Arabidopsis aba4-1 Mutant Reveals a Specific Function for Neoxanthin in Protection against Photooxidative Stress[W

    Science.gov (United States)

    Dall'Osto, Luca; Cazzaniga, Stefano; North, Helen; Marion-Poll, Annie; Bassi, Roberto

    2007-01-01

    The aba4-1 mutant completely lacks neoxanthin but retains all other xanthophyll species. The missing neoxanthin in light-harvesting complex (Lhc) proteins is compensated for by higher levels of violaxanthin, albeit with lower capacity for photoprotection compared with proteins with wild-type levels of neoxanthin. Detached leaves of aba4-1 were more sensitive to oxidative stress than the wild type when exposed to high light and incubated in a solution of photosensitizer agents. Both treatments caused more rapid pigment bleaching and lipid oxidation in aba4-1 than wild-type plants, suggesting that neoxanthin acts as an antioxidant within the photosystem II (PSII) supercomplex in thylakoids. While neoxanthin-depleted Lhc proteins and leaves had similar sensitivity as the wild type to hydrogen peroxide and singlet oxygen, they were more sensitive to superoxide anions. aba4-1 intact plants were not more sensitive than the wild type to high-light stress, indicating the existence of compensatory mechanisms of photoprotection involving the accumulation of zeaxanthin. However, the aba4-1 npq1 double mutant, lacking zeaxanthin and neoxanthin, underwent stronger PSII photoinhibition and more extensive oxidation of pigments than the npq1 mutant, which still contains neoxanthin. We conclude that neoxanthin preserves PSII from photoinactivation and protects membrane lipids from photooxidation by reactive oxygen species. Neoxanthin appears particularly active against superoxide anions produced by the Mehler's reaction, whose rate is known to be enhanced in abiotic stress conditions. PMID:17351115

  4. The Arabidopsis aba4-1 mutant reveals a specific function for neoxanthin in protection against photooxidative stress.

    Science.gov (United States)

    Dall'Osto, Luca; Cazzaniga, Stefano; North, Helen; Marion-Poll, Annie; Bassi, Roberto

    2007-03-01

    The aba4-1 mutant completely lacks neoxanthin but retains all other xanthophyll species. The missing neoxanthin in light-harvesting complex (Lhc) proteins is compensated for by higher levels of violaxanthin, albeit with lower capacity for photoprotection compared with proteins with wild-type levels of neoxanthin. Detached leaves of aba4-1 were more sensitive to oxidative stress than the wild type when exposed to high light and incubated in a solution of photosensitizer agents. Both treatments caused more rapid pigment bleaching and lipid oxidation in aba4-1 than wild-type plants, suggesting that neoxanthin acts as an antioxidant within the photosystem II (PSII) supercomplex in thylakoids. While neoxanthin-depleted Lhc proteins and leaves had similar sensitivity as the wild type to hydrogen peroxide and singlet oxygen, they were more sensitive to superoxide anions. aba4-1 intact plants were not more sensitive than the wild type to high-light stress, indicating the existence of compensatory mechanisms of photoprotection involving the accumulation of zeaxanthin. However, the aba4-1 npq1 double mutant, lacking zeaxanthin and neoxanthin, underwent stronger PSII photoinhibition and more extensive oxidation of pigments than the npq1 mutant, which still contains neoxanthin. We conclude that neoxanthin preserves PSII from photoinactivation and protects membrane lipids from photooxidation by reactive oxygen species. Neoxanthin appears particularly active against superoxide anions produced by the Mehler's reaction, whose rate is known to be enhanced in abiotic stress conditions.

  5. Studies on reduced height mutants in rice

    International Nuclear Information System (INIS)

    Narahari, P.; Bhagwat, S.G.

    1984-01-01

    Two cross-bred derivatives of the mutant TR5xTR17 and TR21 continued to show promise and were advanced to wider scale testing. TR5 was found to carry a semi-dwarfing gene different from that in IR8. New semi-dwarf mutants were screened from M 2 through M 4 from two separate radiation experiments. The gibberellin response of seedlings of mutant and tester strains was evaluated and crosses of tester stocks and mutant semi-dwarfs were made for genetic analyses. (author)

  6. Proteostasis and ageing: insights from long-lived mutant mice.

    Science.gov (United States)

    Sands, William A; Page, Melissa M; Selman, Colin

    2017-10-15

    The global increase in life expectancy is creating significant medical, social and economic challenges to current and future generations. Consequently, there is a need to identify the fundamental mechanisms underlying the ageing process. This knowledge should help develop realistic interventions capable of combatting age-related disease, and thus improving late-life health and vitality. While several mechanisms have been proposed as conserved lifespan determinants, the loss of proteostasis - where proteostasis is defined here as the maintenance of the proteome - appears highly relevant to both ageing and disease. Several studies have shown that multiple proteostatic mechanisms, including the endoplasmic reticulum (ER)-induced unfolded protein response (UPR), the ubiquitin-proteasome system (UPS) and autophagy, appear indispensable for longevity in many long-lived invertebrate mutants. Similarly, interspecific comparisons suggest that proteostasis may be an important lifespan determinant in vertebrates. Over the last 20 years a number of long-lived mouse mutants have been described, many of which carry single-gene mutations within the growth-hormone, insulin/IGF-1 or mTOR signalling pathways. However, we still do not know how these mutations act mechanistically to increase lifespan and healthspan, and accordingly whether mechanistic commonality occurs between different mutants. Recent evidence supports the premise that the successful maintenance of the proteome during ageing may be linked to the increased lifespan and healthspan of long-lived mouse mutants. © 2017 The Authors. The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.

  7. Transcriptional and proteomic analysis of the Aspergillus fumigatus ΔprtT protease-deficient mutant.

    Science.gov (United States)

    Hagag, Shelly; Kubitschek-Barreira, Paula; Neves, Gabriela W P; Amar, David; Nierman, William; Shalit, Itamar; Shamir, Ron; Lopes-Bezerra, Leila; Osherov, Nir

    2012-01-01

    Aspergillus fumigatus is the most common opportunistic mold pathogen of humans, infecting immunocompromised patients. The fungus invades the lungs and other organs, causing severe damage. Penetration of the pulmonary epithelium is a key step in the infectious process. A. fumigatus produces extracellular proteases to degrade the host structural barriers. The A. fumigatus transcription factor PrtT controls the expression of multiple secreted proteases. PrtT shows similarity to the fungal Gal4-type Zn(2)-Cys(6) DNA-binding domain of several transcription factors. In this work, we further investigate the function of this transcription factor by performing a transcriptional and a proteomic analysis of the ΔprtT mutant. Unexpectedly, microarray analysis revealed that in addition to the expected decrease in protease expression, expression of genes involved in iron uptake and ergosterol synthesis was dramatically decreased in the ΔprtT mutant. A second finding of interest is that deletion of prtT resulted in the upregulation of four secondary metabolite clusters, including genes for the biosynthesis of toxic pseurotin A. Proteomic analysis identified reduced levels of three secreted proteases (ALP1 protease, TppA, AFUA_2G01250) and increased levels of three secreted polysaccharide-degrading enzymes in the ΔprtT mutant possibly in response to its inability to derive sufficient nourishment from protein breakdown. This report highlights the complexity of gene regulation by PrtT, and suggests a potential novel link between the regulation of protease secretion and the control of iron uptake, ergosterol biosynthesis and secondary metabolite production in A. fumigatus.

  8. Mutant Brucella abortus membrane fusogenic protein induces protection against challenge infection in mice.

    Science.gov (United States)

    de Souza Filho, Job Alves; de Paulo Martins, Vicente; Campos, Priscila Carneiro; Alves-Silva, Juliana; Santos, Nathalia V; de Oliveira, Fernanda Souza; Menezes, Gustavo B; Azevedo, Vasco; Cravero, Silvio Lorenzo; Oliveira, Sergio Costa

    2015-04-01

    Brucella species can cause brucellosis, a zoonotic disease that causes serious livestock economic losses and represents a public health threat. The mechanism of virulence of Brucella spp. is not yet fully understood. Therefore, it is crucial to identify new molecules that serve as virulence factors to better understand this host-pathogen interplay. Here, we evaluated the role of the Brucella membrane fusogenic protein (Mfp) and outer membrane protein 19 (Omp19) in bacterial pathogenesis. In this study, we showed that B. abortus Δmfp::kan and Δomp19::kan deletion mutant strains have reduced persistence in vivo in C57BL/6 and interferon regulatory factor 1 (IRF-1) knockout (KO) mice. Additionally, 24 h after macrophage infection with a Δmfp::kan or Δomp19::kan strain expressing green fluorescent protein (GFP) approximately 80% or 65% of Brucella-containing vacuoles (BCVs) retained the late endosomal/lysosomal marker LAMP-1, respectively, whereas around 60% of BCVs containing wild-type S2308 were found in LAMP-1-negative compartments. B. abortus Δomp19::kan was attenuated in vivo but had a residual virulence in C57BL/6 and IRF-1 KO mice, whereas the Δmfp::kan strain had a lower virulence in these same mouse models. Furthermore, Δmfp::kan and Δomp19::kan strains were used as live vaccines. Challenge experiments revealed that in C57BL/6 and IRF-1 KO mice, the Δmfp::kan strain induced greater protection than the vaccine RB51 and protection similar that of vaccine S19. However, a Δomp19::kan strain induced protection similar to that of RB51. Thus, these results demonstrate that Brucella Mfp and Omp19 are critical for full bacterial virulence and that the Δmfp::kan mutant may serve as a potential vaccine candidate in future studies. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. Evaluation on selected dwarf and semidwarf mutants of upland rice

    International Nuclear Information System (INIS)

    Riyanti Sumanggono, A.M.

    1984-01-01

    Seratus malam local upland rice variety was irradiated with gamma-rays at doses of O.1, 0.2, 0.3, 0.4 and 0.5 kGy. Observation of radiation effect was carried out on root and shoot length of M 1 seedlings; plant height, panicle length and number of tiller and seed sterility in M 1 plants. Selection for dwarf and semi-dwarf characteristics were done in M 2 plants, and selected again in M 3 . Observation on radiation effect indicated that 'Seratus Malam' seems to be more resistant than the lowland rice varieties. Increasing doses of radiation caused increasing frequency of chlorophyll mutations as well as chlorophyll mutants. Whereas, selection of dwarf or semi-dwarf in M 2 plants seems that mutant and mutation frequencies decreased as the dose increased. Dose of 0.2 kGy was suitable for selection of dwarf or semi-dwarf plants. Plant height could be influenced by environmental condition. Many of the selected M 2 plants were not really dwarf or semi-dwarf mutants. M 3 evaluation of the selected M 2 plants was really beneficial in the mutant selection. (author)

  10. Abnormal grooming activity in Dab1(scm) (scrambler) mutant mice.

    Science.gov (United States)

    Strazielle, C; Lefevre, A; Jacquelin, C; Lalonde, R

    2012-07-15

    Dab1(scm) mutant mice, characterized by cell ectopias and degeneration in cerebellum, hippocampus, and neocortex, were compared to non-ataxic controls for different facets of grooming caused by brief water immersions, as well as some non-grooming behaviors. Dab1(scm) mutants were strongly affected in their quantitative functional parameters, exhibiting higher starting latencies before grooming relative to non-ataxic littermates of the A/A strain, fewer grooming bouts, and grooming components of shorter duration, with an unequal regional distribution targeting almost totally the rostral part (head washing and forelimb licking) of the animal. Only bouts of a single grooming element were preserved. The cephalocaudal order of grooming elements appeared less disorganized, mutant and control mice initiating the grooming with head washing and forelimb licking prior to licking posterior parts. However, mutants differed from controls in that all their bouts were incomplete but uninterrupted, although intergroup difference for percentage of the incorrect transitions was not significant. In contrast to grooming, Dab1(scm) mice ambulated for a longer time. During walking episodes, they exhibited more body scratching than controls, possibly to compensate for the lack of licking different body parts. In conjunction with studies with other ataxic mice, these results indicate that the cerebellar cortex affects grooming activity and is consequently involved in executing various components, but not in its sequential organization, which requires other brain regions such as cerebral cortices or basal ganglia. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. A novel zebrafish mutant with wavy-notochord: an effective biological index for monitoring the copper pollution of water from natural resources.

    Science.gov (United States)

    Chen, Yau-Hung; Lin, Ji-Sheng

    2011-02-01

    We identified a novel zebrafish mutant that has wavy-notochord phenotypes, such as severely twisted notochord and posterior malformations, but has normal melanocytes. Histological evidences showed that proliferating vacuolar cells extended their growth to the muscle region, and consequently caused the wavy-notochord phenotypes. Interestingly, those malformations can be greatly reversed by exposure with copper, suggesting that copper plays an important role on wavy-notochord phenotypes. In addition, after long-term copper exposure, the surviving larvae derived from wavy-notochord mutants displayed bone malformations, such as twisted axial skeleton and osteophyte. These phenotypic changes and molecular evidences of wavy-notochord mutants are highly similar to those embryos whose lysyl oxidases activities have been inactivated. Taken together, we propose that (i) the putative mutated genes of this wavy-notochord mutant might be highly associated with the lysyl oxidase genes in zebrafish; and (ii) this fish model is an effective tool for monitoring copper pollution of water from natural resources. Copyright © 2009 Wiley Periodicals, Inc.

  12. Studies on cytological, physiological and genetic characteristics in somatic mutant strains of Sugi (Cryptomeria japonica D. Don)

    International Nuclear Information System (INIS)

    Maeta, T.; Somegou, M.; Nakahira, K.; Miyazaki, Y.; Kondo, T.

    1982-01-01

    From microscopic observation of the pollen of induced mutant strains in Sugi (Cryptomeria japonica D. Don), it was found that there were large differences in pollen fertility among the mutant strains, and that it deviated year to year from the mother plants. The large differences in frequency of sterile pollen among mutant strains depended on the genetic characteristics of each mutant strain. Higher frequencies of sterile pollen were observed at the terminal part of branchlets in some mutant strains, and this was considered to be induced by the lateness of flower-bud formation at low temperature conditions in late summer. Delayed formation and gibberellic acid treatment applied for flower induction resulted in low fertility and abnormality of pollen in mutant strains. Chromosome aberration in mutant strains was caused either by gamma irradiation or by some mutational events that responded to environmental conditions. In the former case, aberration might have been maintained for a long period through vegetative propagation. Some of the irregularities were due to mitotic cell division, because cells with micronuclei at the pacytene stage in pollen mother cells and with fragments at MI were observed. Somatic mutability of Kuma-sugi mutants after re-irradiation was investigated. From waxless mutants morphological somatic mutations, which have fat or stout stems and thick and short needles, were frequently produced, whereas from morphological mutants the lowest somatic mutation frequency was induced. In some mutant strains higher rooting ability than the mother plants was found, and the possibility of character improvement was pointed out. (author)

  13. Genetic background of Prop1(df) mutants provides remarkable protection against hypothyroidism-induced hearing impairment.

    Science.gov (United States)

    Fang, Qing; Giordimaina, Alicia M; Dolan, David F; Camper, Sally A; Mustapha, Mirna

    2012-04-01

    Hypothyroidism is a cause of genetic and environmentally induced deafness. The sensitivity of cochlear development and function to thyroid hormone (TH) mandates understanding TH action in this sensory organ. Prop1(df) and Pou1f1(dw) mutant mice carry mutations in different pituitary transcription factors, each resulting in pituitary thyrotropin deficiency. Despite the same lack of detectable serum TH, these mutants have very different hearing abilities: Prop1(df) mutants are mildly affected, while Pou1f1(dw) mutants are completely deaf. Genetic studies show that this difference is attributable to the genetic backgrounds. Using embryo transfer, we discovered that factors intrinsic to the fetus are the major contributor to this difference, not maternal effects. We analyzed Prop1(df) mutants to identify processes in cochlear development that are disrupted in other hypothyroid animal models but protected in Prop1(df) mutants by the genetic background. The development of outer hair cell (OHC) function is delayed, but Prestin and KCNQ4 immunostaining appear normal in mature Prop1(df) mutants. The endocochlear potential and KCNJ10 immunostaining in the stria vascularis are indistinguishable from wild type, and no differences in neurofilament or synaptophysin staining are evident in Prop1(df) mutants. The synaptic vesicle protein otoferlin normally shifts expression from OHC to IHC as temporary afferent fibers beneath the OHC regress postnatally. Prop1(df) mutants exhibit persistent, abnormal expression of otoferlin in apical OHC, suggesting delayed maturation of synaptic function. Thus, the genetic background of Prop1(df) mutants is remarkably protective for most functions affected in other hypothyroid mice. The Prop1(df) mutant is an attractive model for identifying the genes that protect against deafness.

  14. Plant injury due to air pollution - similar symptoms. Part I

    Energy Technology Data Exchange (ETDEWEB)

    Matsuoka, Y

    1976-01-01

    Many plant diseases cause injuries to leaves which mimic the damage inflicted by air pollution. The relationship between air pollution injuries and those caused by meteorological conditions are discussed. Rice plants often contract akagare which causes reddish-brown spots on leaves similar to the symptoms caused by photochemical oxidants. Spider mites produce leaf damage in kidney beans which mimics the spotting caused by photochemical oxidants. Lace bugs produce minute white spots on azaleas similar to those caused by photochemical oxidants.

  15. Characterization of Boerhavia diffusa L. mutant lines by RAPD and isozyme, selected for agronomically valuable traits

    International Nuclear Information System (INIS)

    Shukla, N.; Sangwan, N.S.; Misra, H.O.; Sangwan, R.S.

    2004-01-01

    Boerhavia diffusa is a medicinally important plant and finds extensive uses in traditional herbal drug preparations. For the development of improved varieties in terms of superior yield and quality of herb/root of B. diffusa, mutation breeding was attempted. Mutants generated by physical and chemical mutagenic treatments were screened for yield and quality parameters of the root/herb up to three consecutive generations. The selected-screened lines generated by physical and chemical mutagenic treatments on two selected genotypes I and II were molecularly analyzed using eight isozymes and eleven RAPD primers producing good amplification. Mutants from BD10 (selected genotype I) were distinct, while, in case of BD22 (selected genotype II), only one mutant BDMu7 was recorded distinct by isozyme analysis. The wild mutant (BDMu16, with maximum height and mouve coloured flower) was distinct in RAPD banding pattern. Isozymes differentiated the mutants from their respective controls, whereas RAPD differentiated the mutants and controls and also distinguished the mutants. The RAPD analysis was found to be better suited than isozymes for detecting genetic differences among controls and their mutants. However, both RAPD and isozyme analyses gave similar patterns of genetic relationships [it

  16. Photosynthetic Characteristics of Flag Leaves in Rice White Stripe Mutant 6001 During Senescence Process

    Directory of Open Access Journals (Sweden)

    Xiao-hui ZHEN

    2014-11-01

    Full Text Available Physiological, biochemical and electron microscopy analyses were used to investigate the photosynthetic performance of flag leaves in rice white stripe mutant 6001 during the senescence process. Results showed that the chlorophyll content at the heading and milk-ripe stages in rice mutant 6001 were about 34.78% and 3.00% less than those in wild type 6028, respectively. However, the chlorophyll content at the fully-ripe stage in rice mutant 6001 was higher than that in wild type 6028. At the heading stage, the net photosynthetic rate (Pn in rice mutant 6001 was lower than that in wild type 6028. Rice mutant 6001 also exhibited a significantly slower decrease rate of Pn than wild type 6028 during the senescence progress, especially at the later stage. Furthermore, Ca2+-ATPase, Mg2+-ATPase and photophosphorylation activities exhibited the similar trends as the Pn. During the senescence process, the 68 kDa polypeptide concentrations in the thylakoid membrane proteins exhibited a significant change, which was one of the critical factors that contributed to the observed change in photosynthesis. We also observed that the chloroplasts of rice mutant 6001 exhibited higher integrity than those of wild type 6028, and the chloroplast membrane of rice mutant 6001 disintegrated more slow during the senescence process. In general, rice mutant 6001 had a relatively slower senescence rate than wild type 6028, and exhibited anti-senescence properties.

  17. Generation and characterization of pigment mutants of ...

    African Journals Online (AJOL)

    Compared to the wild CC-124, these mutants are characterized by a decrease in chlorophyll a & b content and an increase in carotenoids. The lowest decrease in chlorophyll a was 3 to 4 folds, while the highest increase in carotenoids was 2 to 4 folds. The result of bio-test, using the resulting pigment mutant of C. reinhardtii ...

  18. Differential effects of lesion mimic mutants in barley on disease development by facultative pathogens

    Science.gov (United States)

    McGrann, Graham R. D.; Steed, , Andrew; Burt, Christopher; Nicholson, Paul; Brown, James K. M.

    2015-01-01

    Lesion mimic mutants display spontaneous necrotic spots and chlorotic leaves as a result of mis-regulated cell death programmes. Typically these mutants have increased resistance to biotrophic pathogens but their response to facultative fungi that cause necrotrophic diseases is less well studied. The effect of altered cell death regulation on the development of disease caused by Ramularia collo-cygni, Fusarium culmorum and Oculimacula yallundae was explored using a collection of barley necrotic (nec) lesion mimic mutants. nec8 mutants displayed lower levels of all three diseases compared to nec9 mutants, which had increased R. collo-cygni but decreased F. culmorum disease symptoms. nec1 mutants reduced disease development caused by both R. collo-cygni and F. culmorum. The severity of the nec1-induced lesion mimic phenotype and F. culmorum symptom development was reduced by mutation of the negative cell death regulator MLO. The significant reduction in R. collo-cygni symptoms caused by nec1 was completely abolished in the presence of the mlo-5 allele and both symptoms and fungal biomass were greater than in the wild-type. These results indicate that physiological pathways involved in regulation of cell death interact with one another in their effects on different fungal pathogens. PMID:25873675

  19. SRAP analysis for space induced mutant line of maize (Zea mays L.)

    International Nuclear Information System (INIS)

    Du Wenping; Yu Guirong; Song Jun; Xu Liyuan

    2011-01-01

    In order to detect the effects of space mutation on maize, 16 SRAP primers were applied for the discrimination of the maize inbred line '968' and its 93 mutant materials, 154 polymorphic fragments were amplified. The average of polymorphic bands detected by per SRAP primer combination was 9.6 with a range from 5 to 18. Genetic similarities among the 94 materials ranged from 0.481 to 1.000 with an average of 0.903, and the largest genetic distance was found between mutant line 37 and control. The 94 materials were divided into six groups with the similarity coefficient of 0.732. The phylogenetic analysis showed distinct variation among the mutants. The results indicated that SRAP markers could be used for analyzing genetic variation of mutants. (authors)

  20. Analysis of nutritional quality of low phytic acid mutants in maize

    International Nuclear Information System (INIS)

    Yuan Ming'an; Luo Hongbing; Wang Zhonghua; Chen Jinhong; Mei Shufang; Shu Xiaoli; Wu Dianxing

    2008-01-01

    Major nutritional quality and components of eight low phytic acid (lpa) mutants and their corresponding wild types were studied. Compared to their corresponding wild types, the content of inorganic P (Pi) was all increased several times, while the content of total P (TP) in mutants was almost the same as their wild types. The contents of crude lipid and amylose were similar, but total starch was significantly different. Crude protein in some of mutants was increased significantly. Most of amino acids were increased, and essential amino acid-Lysine was increased except mutants derived from Q319 and X178. Mineral macronutrients and micronutrients were similar. All results showed that the lpa mutation in maize could enhance the nutritional quality and bioactivities. (authors)

  1. A mutant of a mutant of a mutant of a ...: Irradiation of progressive radiation-induced mutants in a mutation-breeding programme with Chrysanthenum morifolium RAM

    International Nuclear Information System (INIS)

    Broertjes, C.; Koene, P.; Veen, J.W.H. van.

    1980-01-01

    Radiation-induced sports in Chrysanthemum morifolium RAM. have been reported for several years. It has become an everyday practice to produce flower-colour mutants from outstanding cross-breeding products, even before they are distributed for the commercial production of cut flowers. One of the most successful and recent examples is that of cv. Horim, of which hundreds of mutants were produced by successive use of radiation-induced mutants in the mutation-breeding programme. Over about 4 years a variety of flower-colour mutants was obtained, not only largely including the outstanding characteristics of the original cultivar but sometimes even with an appreciable improvement in quality and yield. It is expected that the latter types, the Miros group, will soon completely supersede the spontaneous or raditation-induced Horim sports and mutants and take over the leading position of the Horim group in the production of all-year-round (AYR) cut-flowers. (orig.)

  2. Purification, crystallization and preliminary X-ray diffraction analysis of disease-related mutants of p97

    International Nuclear Information System (INIS)

    Tang, Wai-Kwan; Li, Dongyang; Esser, Lothar; Xia, Di

    2009-01-01

    Mutations in the human AAA+ protein p97 cause a disease in humans called IBMPFD. How these mutations affect the structure and function of p97 is unknown. Here, the crystallization of three disease-related mutants of p97 in the presence of ATPγS are reported. The human type II AAA+ protein p97 participates in various cellular activities, presumably through its involvement in the ubiquitin–proteasome degradation pathway. Mutations in p97 have been implicated in patients with inclusion-body myopathy associated with Paget’s disease of the bone and frontotemporal dementia (IBMPFD). In this work, three mutant p97 N-D1 fragments, R86A, R95G and R155H, were crystallized in the presence of ATPγS with PEG 3350 as a main precipitant, yielding two different crystal forms. The R155H mutant crystal belonged to space group R3, with unit-cell parameters in the hexagonal setting of a = b = 134.2, c = 182.9 Å, and was merohedrally twinned, with an estimated twin fraction of 0.34. The crystals of the R86A and R95G mutants belonged to space group P1, with similar unit-cell parameters of a = 90.89, b = 102.6, c = 107.2 Å, α = 97.5, β = 90.6, γ = 91.5° and a = 92.76, b = 103.7, c = 107.7 Å, α = 97.7, β = 91.9, γ = 89.7°, respectively

  3. Zebrafish enpp1 mutants exhibit pathological mineralization, mimicking features of generalized arterial calcification of infancy (GACI and pseudoxanthoma elasticum (PXE

    Directory of Open Access Journals (Sweden)

    Alexander Apschner

    2014-07-01

    Full Text Available In recent years it has become clear that, mechanistically, biomineralization is a process that has to be actively inhibited as a default state. This inhibition must be released in a rigidly controlled manner in order for mineralization to occur in skeletal elements and teeth. A central aspect of this concept is the tightly controlled balance between phosphate, a constituent of the biomineral hydroxyapatite, and pyrophosphate, a physiochemical inhibitor of mineralization. Here, we provide a detailed analysis of a zebrafish mutant, dragonfish (dgf, which is mutant for ectonucleoside pyrophosphatase/phosphodiesterase 1 (Enpp1, a protein that is crucial for supplying extracellular pyrophosphate. Generalized arterial calcification of infancy (GACI is a fatal human disease, and the majority of cases are thought to be caused by mutations in ENPP1. Furthermore, some cases of pseudoxanthoma elasticum (PXE have recently been linked to ENPP1. Similar to humans, we show here that zebrafish enpp1 mutants can develop ectopic calcifications in a variety of soft tissues – most notably in the skin, cartilage elements, the heart, intracranial space and the notochord sheet. Using transgenic reporter lines, we demonstrate that ectopic mineralizations in these tissues occur independently of the expression of typical osteoblast or cartilage markers. Intriguingly, we detect cells expressing the osteoclast markers Trap and CathepsinK at sites of ectopic calcification at time points when osteoclasts are not yet present in wild-type siblings. Treatment with the bisphosphonate etidronate rescues aspects of the dgf phenotype, and we detected deregulated expression of genes that are involved in phosphate homeostasis and mineralization, such as fgf23, npt2a, entpd5 and spp1 (also known as osteopontin. Employing a UAS-GalFF approach, we show that forced expression of enpp1 in blood vessels or the floorplate of mutant embryos is sufficient to rescue the notochord

  4. physical, chemical, technological and biological properties of some mutant oil seeds induced by gamma radiation

    International Nuclear Information System (INIS)

    Ali, H.G.M.

    2003-01-01

    The present study has been undertaken to evaluated sesame, sunflower and safflower seeds induced by gamma rays, as plant breeding unit, plant research department, radioisotope application division, nuclear research center, atomic energy authority Inshas. the obtained results indicate the following : chemical composition of mutant seeds: the radiation mutation caused a significant increase in both oil and ash content total carbohydrates showed a significant decreased in sesame seeds. radiation mutation induced significant increase in oil and protein content of sunflower and safflower seeds. while the total carbohydrate showed a significant decrease. physiochemical properties of oils extracted mutant seeds: the radiation mutation had no real effect on the refractive index and A.V of oils extracted from control and mutant sesame, sunflower and safflower seeds. while it caused a slight increase in red color and P.V. of sesame oil, the thiobarbituric acid (TBA) value of mutant sesame oil was not alter upon radiation mutation, but it induced a slight decrease in TBA of mutant sunflower and safflower oils. the unsaponifiable matter percentage of oils extracted from mutant sesame, sunflower and safflower seeds were slightly increased by radiation mutation .radiation mutation of seeds had no real effect on the total SFA and USFA of sesame oil. however, radiation mutation induced a remarkable changes in fatty acid profiles of sunflower and safflower oil as total SFA decreased, while USFA increased. Uric acid was only detected in oil extracted from mutant sunflower seeds

  5. Los mutantes de la escuela

    Directory of Open Access Journals (Sweden)

    Diego Armando Jaramillo-Ocampo

    2013-01-01

    Full Text Available El presente artículo muestra los resultados parciales del estudio “Juegos en el recreo escolar: un escenario para la formación ciudadana”, cuya pretensión fue comprender los imaginarios sociales de juego en el recreo escolar y su relación con la convivencia social desde la proximidad del enfoque de complementariedad y el diseño de investigación emergente, planteado por Murcia y Jaramillo (2008. Se presentan los desarrollos logrados en dos categorías centrales del estudio: el patio y el cuerpo; dos categorías que mutan constantemente como entidades vivas en la escuela, hacia la configuración de sujetos que reconocen en el otro y lo otro su posibilidad. La escuela viva, donde es posible “ser en relación con”… se reduce a un espacio temporal y físico, limitado por la campana, “el recreo”. El texto muestra, desde la voz de los actores, esa vida que se da y se quita en la escuela y que se posiciona como una más de las imposiciones normalizadas para controlar. Reconoce, finalmente, una propuesta desde la posibilidad que estos dos mutantes propician para una escuela libre y dinámica.

  6. Absence-like and tonic seizures in aspartoacylase/attractin double-mutant mice.

    Science.gov (United States)

    Gohma, Hiroshi; Kuramoto, Takashi; Matalon, Reuben; Surendran, Sankar; Tyring, Stephen; Kitada, Kazuhiro; Sasa, Masashi; Serikawa, Tadao

    2007-04-01

    The Spontaneously Epileptic Rat (SER), a double-mutant for tremor and zitter mutations, shows spontaneous occurrences of absence-like and tonic seizures. Several lines of evidence suggest that the combined effect of Aspa and Atrn mutations is the most likely cause of the epileptic phenotype of the SER. To address this issue, we produced a new double-mutant mouse line carrying both homozygous Aspa-knockout and Atrn(mg-3J) mutant alleles. The Aspa/Atrn double-mutant mice exhibited absence-like and tonic seizures that were characterized by the appearance of 5-7 Hz spike-wave-like complexes and low voltage fast waves on EEGs. These results demonstrate directly that the simultaneous loss of the Aspa and Atrn gene functions causes epileptic seizures in the mouse and suggest that both Aspa and Atrn deficiencies might be responsible for epileptic seizures in the SER.

  7. Mutant of Japanese pear resistant to Black Spot Disease

    International Nuclear Information System (INIS)

    Sanada, T.; Nishida, T.; Ikeda, F.

    1987-01-01

    Full text: Nijisseike is one of the leading cultivars of Japanese pear (Pyrus serotinea Rehd.), but susceptible to black spot disease. Farmers try to prevent this disease by wrapping the fruit with a paper bag and by repeated spraying of fungicides. The disease is caused by a Japanese pear pathotype of Alternaria alternata (Fr.) Keissler. Susceptibility is controlled by a single dominant gene. In 1962, grafted trees of this cultivar were planted at a distance between 53 and 93 m from the 60 Co source in the gamma-field (daily dose 15-4 rad). One branch on a tree planted at 53 m was detected as resistant in 1981. Under field conditions, black spots were observed on many fruits and leaves of the original trees by natural infection in early July, however, they were not observed on the mutant. To examine the resistance of the mutant, artificial inoculations were made using spores of the pathogen and the host specific toxin produced by germinating spores. When some drops of the spore suspension are placed on leaves, the formation of black spots depends upon the leaf age. In a resistant cv. as Chojuro, black spot symptoms are formed only when inoculated on young leaves. An intermediate reaction was observed in the mutant, whereas the original Nijisseiki showed severe symptoms. When inoculation was made on matured fruit skins, no black spot was formed on the mutant just like on the resistant cv. Chojuro, while many small black spots were formed and grew into large spots overlapping each other on the susceptible cv. Nijisseiki. In case of the crude toxin inoculation (4-0.04 ppm) of cv. Nijisseiki black spots were formed on the surface of the susceptible fruit skin, and necrotic lesions at the cut end of detached small pieces of leaves, although reaction on fruit skins was weaker compared with inoculation by spores. However, no symptoms were observed from the toxin application on the mutant and the resistant cv. Chojuro. That the resistance of the mutant is classified as

  8. Mutants dissecting development and behaviour in drosophila

    International Nuclear Information System (INIS)

    Joshi, Adita; Chandrashekaran, Shanti; Sharma, R.P.

    2005-01-01

    We have traced in this paper the progress in Drosophila genetics research from the 1960s, at the IARI, spearheaded by the visionary insight of M. S. Swaminathan. The work started with the study of indirect effect of radiation and the synergistic interaction of physical and chemical mutagens on chromosomal and genetic changes. This paved the way for the study of single gene mutants in dissecting developmental and behavioural processes. New genes discovered by us have been shown to encode conserved cell signalling molecules controlling developmental and behavioural pathways. With the complete sequencing of the Drosophila genome, in the year 2000, mounting evidence for the homology between Drosophila and human genes controlling genetic disorders became available. This has led to the fly becoming an indispensable tool for studying human diseases as well as a model to test for drugs and pharmaceuticals against human diseases and complex behavioural processes. For example wingless in Drosophila belongs to the conserved Wnt gene family and aberrant WNT signalling is linked to a range of human diseases, most notably cancer. Inhibition as well as activation of WNT signalling form the basis of an effective therapy for some cancers as well as several other clinical conditions. Recent experiments have shown that WNTs might also normally participate in self-renewal, proliferation or differentiation of stem cells and altering WNT signalling might be beneficial to the use of stem cells for therapeutic means. Likewise, the stambhA mutant of Drosophila which was discovered for its temperature-dependent paralytic behaviour is the fly homologue of Phospholipase Cβ. Phospholipase C mediated G protein signalling plays a central role in vital processes controlling epilepsy, vision, taste, and olfaction in animals. Proteins of the G-signalling pathway are of intense research interest since many human diseases involve defects in G-protein signalling pathways. In fact, approximately 50

  9. Mutants of GABA transaminase (POP2 suppress the severe phenotype of succinic semialdehyde dehydrogenase (ssadh mutants in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Frank Ludewig

    Full Text Available BACKGROUND: The gamma-aminubutyrate (GABA shunt bypasses two steps of the tricarboxylic acid cycle, and is present in both prokaryotes and eukaryotes. In plants, the pathway is composed of the calcium/calmodulin-regulated cytosolic enzyme glutamate decarboxylase (GAD, the mitochondrial enzymes GABA transaminase (GABA-T; POP2 and succinic semialdehyde dehydrogenase (SSADH. We have previously shown that compromising the function of the GABA-shunt, by disrupting the SSADH gene of Arabidopsis, causes enhanced accumulation of reactive oxygen intermediates (ROIs and cell death in response to light and heat stress. However, to date, genetic investigations of the relationships between enzymes of the GABA shunt have not been reported. PRINCIPAL FINDINGS: To elucidate the role of succinic semialdehyde (SSA, gamma-hydroxybutyrate (GHB and GABA in the accumulation of ROIs, we combined two genetic approaches to suppress the severe phenotype of ssadh mutants. Analysis of double pop2 ssadh mutants revealed that pop2 is epistatic to ssadh. Moreover, we isolated EMS-generated mutants suppressing the phenotype of ssadh revealing two new pop2 alleles. By measuring thermoluminescence at high temperature, the peroxide contents of ssadh and pop2 mutants were evaluated, showing that only ssadh plants accumulate peroxides. In addition, pop2 ssadh seedlings are more sensitive to exogenous SSA or GHB relative to wild type, because GHB and/or SSA accumulate in these plants. SIGNIFICANCE: We conclude that the lack of supply of succinate and NADH to the TCA cycle is not responsible for the oxidative stress and growth retardations of ssadh mutants. Rather, we suggest that the accumulation of SSA, GHB, or both, produced downstream of the GABA-T transamination step, is toxic to the plants, resulting in high ROI levels and impaired development.

  10. Characteristic, inheritance and breeding application of rice mutants with greenable albino leaf

    International Nuclear Information System (INIS)

    Fang Xiantao; Ma Hongli; Zhao Fuyuan; Zhang Qingqi; Zhang Shubiao

    2009-01-01

    Inheritance and main agronomic traits of photo-thermo-sensitive genic male sterile line with green-revertible albino leaf were investigated. The results indicated that the mutants might be divided into three types: albino regreening type (W2, W3, W4 and W10), albino to kelly type (W9) and abino-regreening-albino-regreening type (W1 and W7). Genetic study indicated that green-revertible albino leaf color trait of the mutants as controlled by a single recessive gene. These mutants had similar agronomic traits and fertility characteristics to the corresponding male sterile line 'Peiai 64S'. The hybrids of these mutants had similar characteristics with original-hybrids in plant type, developing of tillers and plant height. The yield components of the mutant hybrids were different depending on different mutants. The yield potential of hybrids of W1, W2 and W3 were similar to the original-hybrid. The results also indicated that W1, W2 and W3 had breeding application value. (authors)

  11. NetB, a new toxin that is associated with avian necrotic enteritis caused by Clostridium perfringens.

    Directory of Open Access Journals (Sweden)

    Anthony L Keyburn

    2008-02-01

    Full Text Available For over 30 years a phospholipase C enzyme called alpha-toxin was thought to be the key virulence factor in necrotic enteritis caused by Clostridium perfringens. However, using a gene knockout mutant we have recently shown that alpha-toxin is not essential for pathogenesis. We have now discovered a key virulence determinant. A novel toxin (NetB was identified in a C. perfringens strain isolated from a chicken suffering from necrotic enteritis (NE. The toxin displayed limited amino acid sequence similarity to several pore forming toxins including beta-toxin from C. perfringens (38% identity and alpha-toxin from Staphylococcus aureus (31% identity. NetB was only identified in C. perfringens type A strains isolated from chickens suffering NE. Both purified native NetB and recombinant NetB displayed cytotoxic activity against the chicken leghorn male hepatoma cell line LMH; inducing cell rounding and lysis. To determine the role of NetB in NE a netB mutant of a virulent C. perfringens chicken isolate was constructed by homologous recombination, and its virulence assessed in a chicken disease model. The netB mutant was unable to cause disease whereas the wild-type parent strain and the netB mutant complemented with a wild-type netB gene caused significant levels of NE. These data show unequivocally that in this isolate a functional NetB toxin is critical for the ability of C. perfringens to cause NE in chickens. This novel toxin is the first definitive virulence factor to be identified in avian C. perfringens strains capable of causing NE. Furthermore, the netB mutant is the first rationally attenuated strain obtained in an NE-causing isolate of C. perfringens; as such it has considerable vaccine potential.

  12. Induction of Mutants in Durum Wheat

    International Nuclear Information System (INIS)

    AL-Ubaidi, M.; Ibrahim, I.; AL-Hadithi, A.

    2002-01-01

    This investigation presents a breeding program for induction and development of a new genotype of durum wheat, resistant to lodging with high yield, by irradiation durum wheat hybrids (F2) with gamma rays 100 Gy, during 1990-1997 cultivation seasons. This program involves: induction of variability, selection evaluation of the mutants at three locations: Twaitha (Baghdad) Latifya ( Babylon) and Swari (Kutt). All mutants showed resistance to lodging and there was a significant reduction in plant height. Mutant SIXIZ-22 surpassed other mutants and its origin in lodging resistance and plant height (83.5,82.8 and 89.4 cm) in the three locations at generation M5 and M6, respectively. Also, there were significant differences between mutant and their origin in the number of spikes/M 2 and grain yild during the two successive generation. On the other hand, mutant IZxCO-105 surpassed other mutants in the number of spikes/M 2 (231.8,242.3 and 292) and grain yield (4336,3376 and 5232 kg/ha) in all testing location, respectively . (authors) 14 refs., 4 tabs

  13. A double-mutant collection targeting MAP kinase related genes in Arabidopsis for studying genetic interactions.

    Science.gov (United States)

    Su, Shih-Heng; Krysan, Patrick J

    2016-12-01

    Mitogen-activated protein kinase cascades are conserved in all eukaryotes. In Arabidopsis thaliana there are approximately 80 genes encoding MAP kinase kinase kinases (MAP3K), 10 genes encoding MAP kinase kinases (MAP2K), and 20 genes encoding MAP kinases (MAPK). Reverse genetic analysis has failed to reveal abnormal phenotypes for a majority of these genes. One strategy for uncovering gene function when single-mutant lines do not produce an informative phenotype is to perform a systematic genetic interaction screen whereby double-mutants are created from a large library of single-mutant lines. Here we describe a new collection of 275 double-mutant lines derived from a library of single-mutants targeting genes related to MAP kinase signaling. To facilitate this study, we developed a high-throughput double-mutant generating pipeline using a system for growing Arabidopsis seedlings in 96-well plates. A quantitative root growth assay was used to screen for evidence of genetic interactions in this double-mutant collection. Our screen revealed four genetic interactions, all of which caused synthetic enhancement of the root growth defects observed in a MAP kinase 4 (MPK4) single-mutant line. Seeds for this double-mutant collection are publicly available through the Arabidopsis Biological Resource Center. Scientists interested in diverse biological processes can now screen this double-mutant collection under a wide range of growth conditions in order to search for additional genetic interactions that may provide new insights into MAP kinase signaling. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  14. Establishment of screening technique for mutant cell and analysis of base sequence in the mutation

    International Nuclear Information System (INIS)

    Sofuni, Toshio; Nomi, Takehiko; Yamada, Masami; Masumura, Kenichi

    2000-01-01

    This research project aimed to establish an easy and quick detection method for radiation-induced mutation using molecular-biological techniques and an effective analyzing method for the molecular changes in base sequence. In this year, Spi mutants derived from γ-radiation exposed mouse were analyzed by PCR method and DNA sequence method. Male transgenic mice were exposed to γ-ray at 5,10, 50 Gy and the transgene was taken out from the genome DNA from the spleen in vivo packaging method. Spi mutant plaques were obtained by infecting the recovered phage to E. coli. Sequence analysis for the mutants was made using ALFred DNA sequencer and SequiTherm TM Long-Red Cycle sequencing kit. Sequence analysis was carried out for 41 of 50 independent Spi mutants obtained. The deletions were classified into 4 groups; Group 1 included 15 mutants that were characterized with a large deletion (43 bp-10 kb) with a short homologous sequence. Group 2 included 11 mutants of a large deletion having no homologous sequence at the connecting region. Group 3 included 11 mutants having a short deletion of less than 20 bp, which occurred in the non-repetitive sequence of gam gene and possibly caused by oxidative breakage of DNA or recombination of DNA fragment produced by the breakage. Group 4 included 4 mutants having deletions as short as 20 bp or less in the repetitive sequence of gam gene, resulting in an alteration of the reading frame. Thus, the synthesis of Gam protein was terminated by the appearance of TGA between code 13 and 14 of redB gene, leading to inactivation of gam gene and redBA gene. These results indicated that most of Spi mutants had a deletion in red/gam region and the deletions in more than half mutants occurred in homologous sequences as short as 8 bp. (M.N.)

  15. Similarity-based pattern analysis and recognition

    CERN Document Server

    Pelillo, Marcello

    2013-01-01

    This accessible text/reference presents a coherent overview of the emerging field of non-Euclidean similarity learning. The book presents a broad range of perspectives on similarity-based pattern analysis and recognition methods, from purely theoretical challenges to practical, real-world applications. The coverage includes both supervised and unsupervised learning paradigms, as well as generative and discriminative models. Topics and features: explores the origination and causes of non-Euclidean (dis)similarity measures, and how they influence the performance of traditional classification alg

  16. Spectrum of induced floral mutants in Petunia

    International Nuclear Information System (INIS)

    Padmaja, V.; Sudhakar, P.

    1987-01-01

    A total of six floral mutants of garden Petunia isolated from the populations raised from the seed treatment with γ-rays, 2, 4-D and sodium azide are described. Five of the mutants viz. stellata, Campyloflora, Rubriflora mixed, Grandiflora and Albiflora mixed originated as segregants in M 2 generation while the chimeral floral phenotype was expressed in M 1 generation itself. Breeding behaviour of these horticulturally interesting altered floral phenotypes were studied in subsequent generations and appropriate conclusions were drawn regarding mode of inheritance of the mutant traits. 15 refs., 4 figures, 1 table. (author)

  17. The Neurospora rca-1 gene complements an Aspergillus flbD sporulation mutant but has no identifiable role in Neurospora sporulation.

    OpenAIRE

    Shen, W C; Wieser, J; Adams, T H; Ebbole, D J

    1998-01-01

    The Aspergillus nidulans flbD gene encodes a protein with a Myb-like DNA-binding domain that is proposed to act in concert with other developmental regulators to control initiation of conidiophore development. We have identified a Neurospora crassa gene called rca-1 (regulator of conidiation in Aspergillus) based on its sequence similarity to flbD. We found that N. crassa rca-1 can complement the conidiation defect of an A. nidulans flbD mutant and that induced expression of rca-1 caused coni...

  18. Characterization of novel Sorghum brown midrib mutants from an EMS-mutagenized population.

    Science.gov (United States)

    Sattler, Scott E; Saballos, Ana; Xin, Zhanguo; Funnell-Harris, Deanna L; Vermerris, Wilfred; Pedersen, Jeffrey F

    2014-09-02

    Reducing lignin concentration in lignocellulosic biomass can increase forage digestibility for ruminant livestock and saccharification yields of biomass for bioenergy. In sorghum (Sorghum bicolor (L.) Moench) and several other C4 grasses, brown midrib (bmr) mutants have been shown to reduce lignin concentration. Putative bmr mutants isolated from an EMS-mutagenized population were characterized and classified based on their leaf midrib phenotype and allelism tests with the previously described sorghum bmr mutants bmr2, bmr6, and bmr12. These tests resulted in the identification of additional alleles of bmr2, bmr6, and bmr12, and, in addition, six bmr mutants were identified that were not allelic to these previously described loci. Further allelism testing among these six bmr mutants showed that they represented four novel bmr loci. Based on this study, the number of bmr loci uncovered in sorghum has doubled. The impact of these lines on agronomic traits and lignocellulosic composition was assessed in a 2-yr field study. Overall, most of the identified bmr lines showed reduced lignin concentration of their biomass relative to wild-type (WT). Effects of the six new bmr mutants on enzymatic saccharification of lignocellulosic materials were determined, but the amount of glucose released from the stover was similar to WT in all cases. Like bmr2, bmr6, and bmr12, these mutants may affect monolignol biosynthesis and may be useful for bioenergy and forage improvement when stacked together or in combination with the three previously described bmr alleles. Copyright © 2014 Sattler et al.

  19. Behaviour of UV-sensitive mutants of Proteus mirabilis to repair incision breaks

    International Nuclear Information System (INIS)

    Stoerl, K.; Mund, C.

    1977-01-01

    In U.V.-sensitive mutants of P. mirabilis with the phenotype HCR, REC and EXR single-strand breaks appeared immediately after UV-irradiation. The behaviour of REC- and EXR-mutants was similar to the wildtype. The number of incision breaks observed by sedimentation analysis in these strains was very low. They could be joined during the excision repair process. From the ability of REC- and EXR-strains to rejoin most of the induced single-strand breaks it can be concluded that these strains have approximately the same capacity for excision repair as the wildtype. HCR-mutants of P. mirabilis produced single-strand breaks after UV-irradiation in contrast to HCR-mutants of E. coli. Therefore we suggest that HCR-mutants of P. mirabilis are not completely inhibited in the incision step. The single-strand breaks introduced in the DNA at the beginning of the repair process were not rejoined during further incubation. Experiments with toluenized cells led to the same results. The newly synthesized daughter DNA-strands of UV-irradiated HCR-mutants were of low molecular weight in comparison with those from unirradiated control cells during the repair period. This result is in agreement with the incapability of HCR-mutants to remove the pyrimidine dimers from the parental template strand. (author)

  20. Semi-dwarf mutants for rice improvement

    International Nuclear Information System (INIS)

    Othman, Ramli; Osman, Mohammad; Ibrahim, Rusli

    1990-01-01

    Full text: MARDI and the National University of Malaysia embarked on a programme to induce resistance against blast in rice in 1978. MARDI also obtained semi dwarf mutants of cvs 'Mahsuri', 'Muda', 'Pongsu seribu' and 'Jarum Mas', which are under evaluation. The popular local rice variety 'Manik' was subjected to gamma irradiation (15-40 krad) and 101 promising semidwarf mutants have been obtained following selection in M 2 -M 6 . 29 of them show grain yields of 6.0-7.3 t/ha, compared with 5.7t for 'Manik'. Other valuable mutants were found showing long grain, less shattering, earlier maturity, and glutinous endosperm. One mutant, resistant to brown plant hopper yields 6.3t/ha. (author)

  1. X-rays sensitive mammalian cell mutant

    International Nuclear Information System (INIS)

    Utsumi, Hiroshi

    1982-01-01

    A phenomenon that in x-ray-sensitive mammalian-cell mutants, cellular death due to x-ray radiation was not increased by caffeine, but on the contrary, the dead cells were resuscitated by it was discussed. The survival rate of mutant cells increased by caffein in a low concentration. This suggested that caffeine may have induced some mechanism to produce x-ray resistant mutant cells. Postirradiation treatment with caffeine increased considerably the survival rate of the mutant cells, and this suggested the existence of latent caffeine-sensitive potentially lethal damage repair system. This system, after a few hours, is thought to be substituted by caffeine-resistant repair system which is induced by caffeine, and this may be further substituted by x-ray-resistant repair system. The repair system was also induced by adenine. (Ueda, J.)

  2. Generation and characterization of pigment mutants of ...

    African Journals Online (AJOL)

    acer

    2014-01-08

    Jan 8, 2014 ... aquatic ecosystems were studied. In the present ... logy and photosynthesis research (Stolbov, 1995;. Pedersen ... Microalgal strain and cultivation conditions ..... evaluated for their ecotoxicological effects using 124y-1 mutant.

  3. Production and characterization of radiation-sensitive meiotic mutants of Coprinus cinereus

    International Nuclear Information System (INIS)

    Zolan, M.E.; Tremel, C.J.; Pukkila, P.J.

    1988-01-01

    We have isolated four gamma-sensitive mutants of the basidiomycete Coprinus cinereus. When homozygous, two of these (rad 3-1 and rad 9-1) produce fruiting bodies with very few viable basidiospores, the products of meiosis in this organism. A less radiation-sensitive allele of RAD 3, rad 3-2, causes no apparent meiotic defect in homozygous strains. Quantitative measurements of oidial survival of rad 3-1;rad 9-1 double mutants compared to the single mutants indicated that rad 3-1 and rad 9-1 mutants are defective in the same DNA repair pathway. In the pew viable basidiospores that are produced by these two strains, essentially normal levels of meiotic recombination can be detected. None of the mutants exhibits increased sensitivity to UV radiation. Cytological examination of meiotic chromosomes from mutant and wild-type fruiting bodies showed that rad 3-1 homozygous strains fail to condense and pair homologous chromosomes during prophase I. Although rad 9-1 strains are successful at chromosome pairing, meiosis is usually not completed in these mutants

  4. Histological Characterization of the Dicer1 Mutant Zebrafish Retina

    Directory of Open Access Journals (Sweden)

    Saeed Akhtar

    2015-01-01

    Full Text Available DICER1, a multidomain RNase III endoribonuclease, plays a critical role in microRNA (miRNA and RNA-interference (RNAi functional pathways. Loss of Dicer1 affects different developmental processes. Dicer1 is essential for retinal development and maintenance. DICER1 was recently shown to have another function of silencing the toxicity of Alu RNAs in retinal pigment epithelium (RPE cells, which are involved in the pathogenesis of age related macular degeneration. In this study, we characterized a Dicer1 mutant fish line, which carries a nonsense mutation (W1457Ter induced by N-ethyl-N-nitrosourea mutagenesis. Zebrafish DICER1 protein is highly conserved in the evolution. Zebrafish Dicer1 is expressed at the earliest stages of zebrafish development and persists into late developmental stages; it is widely expressed in adult tissues. Homozygous Dicer1 mutant fish (DICER1W1457Ter/W1457Ter have an arrest in early growth with significantly smaller eyes and are dead at 14–18 dpf. Heterozygous Dicer1 mutant fish have similar retinal structure to that of control fish; the retinal pigment epithelium (RPE cells are normal with no sign of degeneration at the age of 20 months.

  5. A sorghum (Sorghum bicolor mutant with altered carbon isotope ratio.

    Directory of Open Access Journals (Sweden)

    Govinda Rizal

    Full Text Available Recent efforts to engineer C4 photosynthetic traits into C3 plants such as rice demand an understanding of the genetic elements that enable C4 plants to outperform C3 plants. As a part of the C4 Rice Consortium's efforts to identify genes needed to support C4 photosynthesis, EMS mutagenized sorghum populations were generated and screened to identify genes that cause a loss of C4 function. Stable carbon isotope ratio (δ13C of leaf dry matter has been used to distinguishspecies with C3 and C4 photosynthetic pathways. Here, we report the identification of a sorghum (Sorghum bicolor mutant with a low δ13C characteristic. A mutant (named Mut33 with a pale phenotype and stunted growth was identified from an EMS treated sorghum M2 population. The stable carbon isotope analysis of the mutants showed a decrease of 13C uptake capacity. The noise of random mutation was reduced by crossing the mutant and its wildtype (WT. The back-cross (BC1F1 progenies were like the WT parent in terms of 13C values and plant phenotypes. All the BC1F2 plants with low δ13C died before they produced their 6th leaf. Gas exchange measurements of the low δ13C sorghum mutants showed a higher CO2 compensation point (25.24 μmol CO2.mol-1air and the maximum rate of photosynthesis was less than 5μmol.m-2.s-1. To identify the genetic determinant of this trait, four DNA pools were isolated; two each from normal and low δ13C BC1F2 mutant plants. These were sequenced using an Illumina platform. Comparison of allele frequency of the single nucleotide polymorphisms (SNPs between the pools with contrasting phenotype showed that a locus in Chromosome 10 between 57,941,104 and 59,985,708 bps had an allele frequency of 1. There were 211 mutations and 37 genes in the locus, out of which mutations in 9 genes showed non-synonymous changes. This finding is expected to contribute to future research on the identification of the causal factor differentiating C4 from C3 species that can be used

  6. A high yielding, better quality chickpea mutant variety 'NIFA-95'

    International Nuclear Information System (INIS)

    Hassan, S.; Javed, M.A.; Khattak, S.U.K.; Iqbal, M.M.

    2001-01-01

    Chickpea or gram (Cicer arietinum L.) is an important legume crop of Pakistan, grown on over one million hectares annually. The national average yield of the crop is very low (0.5 t/ha) and thus the country had to spent about 2 billion rupees ($ 50 million) on import of pulses. The main causes of low yield are non-availability of genetic sources for resistance to various diseases especially gram blight Ascochyta rabiei (Pass.) Lab., insect pest (Pod borer) and non-adoption of proper production technology by the farmers. This calls for earnest efforts of breeders to evolve high yielding and disease resistant varieties of chickpea for provision of quality seeds to the farming community to increase production of this important crop. Seeds of a highly blight susceptible variety '6153' were irradiated at 200 Gy dose of gamma radiation in 1985 and the promising mutant line CMN-446-4 was selected in M3 generation on the basis of disease resistance, greater number of pods and better plant type. After confirmation of its resistance to blight in M 4 and M 5 , the mutant line was evaluated in various trials at different locations. In the advanced and zonal yield trials during 1993-95, the line CMN-446-4 produced the highest grain yield of 2,600 kg/ha as compared to the rest of the mutants and varieties. The line was also evaluated in the chickpea national uniform yield trial, conducted on over 11 locations in the country during 1993-94. In this trial, the mutant line ranked 3rd by producing an average yield of 1,528 kg/ha as compared to the two check varieties 'Punjab-91' (1,316 kg/ha) and 'Paidar-91' (1,391 kg/ha). The mutant line CMN-446-4 is moderately resistant to gram blight, highly resistant to stored pest (pulse beetle), contains 25.3% more protein as compared to the parental variety 6153 and is also better in nitrogen fixing capacity.The proposal for release of the mutant line CMN-446-4 as a new variety under the name 'NIFA-95' for general cultivation in the rainfed

  7. Molecular analysis of waxy mutants in rice

    International Nuclear Information System (INIS)

    Yatou, O.; Amano, E.

    1990-01-01

    Full text: The 'waxy' gene is a structural gene coding a glycosyl transferase which synthesises amylose in the endosperm tissue. 'Non-waxy' rice cultivars have an active gene and their amylose content is 18-25% depending upon gene performance and modifier genes. In 'waxy' rice, no amylose is found because the enzyme is absent. In mutants induced by gamma rays, neutrons, EI or EMS, amylose content ranged from 0 to 20%, i.e. there are intermediate phenotypes as well. Some of them had the same amount of the enzyme as a 'non-waxy' cultivar, even fully 'waxy' mutants showed a certain amount of the enzyme. This suggests that in mutants there may be no structural change in the enzyme gene but the enzyme produced might be less active. By molecular analysis of the mutants' genes it was found that only two mutants induced by thermal neutrons show structural alterations, the changes in other mutants are either too small to be detected by Southern analysis or are outside the structural gene in question. (author)

  8. Commercialization Of Orchid Mutants For Floriculture Industry

    International Nuclear Information System (INIS)

    Sakinah Ariffin; Zaiton Ahmad

    2014-01-01

    Orchids are the main contributors to cut flower industry in Malaysia with an existing good market and a huge business potential. Orchid industry has been established in Malaysia since 1960s but only started to develop and expand since 1980s. Continuous development of new orchid varieties is essential to meet customers' demands. Orchid mutagenesis research using gamma irradiation at Malaysian Nuclear Agency has successfully generated a number of new orchid varieties with commercial potentials. Therefore, Nuclear Malaysia has collaborated with an industrial partner, Hexagon Green Sdn Bhd (HGSB), to carry out commercialization research on these mutants under a Technofund project entitled 'Pre-Commercialization of Mutant Orchids for Cut Flowers Industry' from July 2011 to July 2014. Through this collaboration, Dendrobium orchid mutant plants developed by Nuclear Malaysia were transferred to HGSB's commercial orchid nursery at Bukit Changgang Agrotechnology Park, Banting, Selangor, for mass-propagation. The activities include evaluations on plant growth performance, flower quality, post harvest and market potential of these mutants. Mutants with good field performance have been identified and filed for Plant Variety Protection (PVP) with Department of Agriculture Malaysia. This paper describes outputs from this collaboration and activities undertaken in commercializing these mutants. (author)

  9. Mutant p53 protein localized in the cytoplasm inhibits autophagy.

    Science.gov (United States)

    Morselli, Eugenia; Tasdemir, Ezgi; Maiuri, Maria Chiara; Galluzzi, Lorenzo; Kepp, Oliver; Criollo, Alfredo; Vicencio, José Miguel; Soussi, Thierry; Kroemer, Guido

    2008-10-01

    The knockout, knockdown or chemical inhibition of p53 stimulates autophagy. Moreover, autophagy-inducing stimuli such as nutrient depletion, rapamycin or lithium cause the depletion of cytoplasmic p53, which in turn is required for the induction of autophagy. Here, we show that retransfection of p53(-/-) HCT 116 colon carcinoma cells with wild type p53 decreases autophagy down to baseline levels. Surprisingly, one third among a panel of 22 cancer-associated p53 single amino acid mutants also inhibited autophagy when transfected into p53(-/-) cells. Those variants of p53 that preferentially localize to the cytoplasm effectively repressed autophagy, whereas p53 mutants that display a prominently nuclear distribution failed to inhibit autophagy. The investigation of a series of deletion mutants revealed that removal of the DNA-binding domain from p53 fails to interfere with its role in the regulation of autophagy. Altogether, these results identify the cytoplasmic localization of p53 as the most important feature for p53-mediated autophagy inhibition. Moreover, the structural requirements for the two biological activities of extranuclear p53, namely induction of apoptosis and inhibition of autophagy, are manifestly different.

  10. Evaluation of artemisia mutant lines conducted from gamma irradiation treatment

    International Nuclear Information System (INIS)

    Ragapadmi Purnamaningsih; EG Lestari; M Syukur

    2010-01-01

    Cases of Malaria diseases attack in Indonesia has been increasing. Plasmodium falciparum the cause of malaria disease is now resistant to the usual medicine. One of malaria medicine which recommended by WHO is artemisinine compound extracted from Artemisia annua L plant. Low artemisinine content is one problem of Artemisia development in Indonesia. Increasing genetic variation using gamma irradiation is one alternative method to improve artemisinin content. In 2007, induce mutation had been done to artemisia seeds using gamma irradiation at dosage of 10-100 Gy. The good rooting planlet was regenerated and acclimatized in the green house, and then the seedling (M0 generation) was planted in the field at 1545 m asl. Plants derived from seeds without gamma irradiation treatment and cultured in vitro (in vitro control) were used as control. The result showed there were some morphological variations between the mutant lines (plant height, shape of the leaves and time of flowering). Ten mutant lines were selected based on biomass yield and analyzed for the artemisinine content.The result showed that artemisinine content of the mutant lines ranged from 0.44 - 1.41%, and it was significantly higher than that of in vitro control (0.43%). (author)

  11. Trehalose, glycogen and ethanol metabolism in the gcr1 mutant of Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Seker, Tamay; Hamamci, H.

    2003-01-01

    Since Gcr1p is pivotal in controlling the transcription of glycolytic enzymes and trehalose metabolism seems to be one of the control points of glycolysis, we examined trehalose and glycogen synthesis in response to 2 % glucose pulse during batch growth in gcr1 (glucose regulation-1) mutant lacking...... fully functional glycolytic pathway and in the wild-type strain. An increase in both trehalose and glycogen stores was observed 1 and 2 h after the pulse followed by a steady decrease in both the wild-type and the gcr1 mutant. The accumulation was faster while the following degradation was slower in gcr......1 cells compared to wild-type ones. Although there was no distinct glucose consumption in the mutant cells it seemed that the glucose repression mechanism is similar in gcr1 mutant and in wild-type strain at least with respect to trehalose and glycogen metabolism....

  12. Study of the UV-sensitivity of the morphological Salmonella typhimurium mutant

    Energy Technology Data Exchange (ETDEWEB)

    Sakanyan, V A; Dombrovskii, A M; Belokrysenko, S S; Levashev, V S [Vtoroj Moskovskij Gosudarstvennyj Meditsinskij Inst. (USSR)

    1975-05-01

    As regards sensitivity to ultraviolet radiation, the morphological mutant S. typhimurium LT2 WT ED 143 is similar to the ion-mutants E. coli K12. Data are presented on the sensitivity of the mutant and initial strains to ultraviolet radiation at various phases of growth, on the capacity for restoring the bacteriophages P22 and Felix O after irradiation and on the influence of various treatments after ultraviolet irradiation (incubation in minimum media and at 42/sup 0/ C) on the irradiated strains. The results of densitometry of the membrane proteins of the initial and mutant strains point to a connection between unusual morphology, the disruption of division and the enhanced sensitivity to ultraviolet radiation on one hand and the state of the membrane components of the bacterial cell on the other.

  13. Radiation induced mutants in elite genetic background for the augmentation of genetic diversity

    International Nuclear Information System (INIS)

    Kumar, V.; Bhagwat, S.G.

    2011-01-01

    Rice (Oryza sativa L.), an important food crop for India, shows large genetic diversity. However, despite the large genetic resource, high genetic similarity is reported in cultivated varieties indicating genetic erosion. Radiation induced mutations provide genetic variability in elite background. In the present study, twenty gamma ray induced mutants of rice variety WL112 (carrying sd-1 semi-dwarfing gene) were analysed for genetic diversity using microsatellite markers. The high range of genetic diversity among mutants indicated that the mutants possess potential for enhancing variability in rice. Cluster analysis showed presence of five clusters having small sub-clusters. Earliness, semi-dwarf stature or resistance to blast disease observed among the mutants showed that these will be useful in breeding programmes. (author)

  14. Characterization of a bacteriophage T4 mutant lacking DNA-dependent ATPase

    International Nuclear Information System (INIS)

    Behme, M.T.; Ebisuzaki, K.

    1975-01-01

    A DNA-dependent ATPase has previously been purified from bacteriophage T4-infected Escherichia coli. A mutant phage strain lacking this enzyme has been isolated and characterized. Although the mutant strain produced no detectable DNA-dependent ATPase, growth properties were not affected. Burst sizes were similar for the mutant phage and T4D in polAl, recB, recC, uvrA, uvrB, uvrC, and various DNA-negative E. coli. UV sensitivity and genetic recombination were normal in a variety of E. coli hosts. Mapping data indicate that the genetic locus controlling the mutant occurs near gene 56. The nonessential nature of this gene is discussed

  15. Molecular Determinants of Mutant Phenotypes, Inferred from Saturation Mutagenesis Data.

    Science.gov (United States)

    Tripathi, Arti; Gupta, Kritika; Khare, Shruti; Jain, Pankaj C; Patel, Siddharth; Kumar, Prasanth; Pulianmackal, Ajai J; Aghera, Nilesh; Varadarajan, Raghavan

    2016-11-01

    Understanding how mutations affect protein activity and organismal fitness is a major challenge. We used saturation mutagenesis combined with deep sequencing to determine mutational sensitivity scores for 1,664 single-site mutants of the 101 residue Escherichia coli cytotoxin, CcdB at seven different expression levels. Active-site residues could be distinguished from buried ones, based on their differential tolerance to aliphatic and charged amino acid substitutions. At nonactive-site positions, the average mutational tolerance correlated better with depth from the protein surface than with accessibility. Remarkably, similar results were observed for two other small proteins, PDZ domain (PSD95 pdz3 ) and IgG-binding domain of protein G (GB1). Mutational sensitivity data obtained with CcdB were used to derive a procedure for predicting functional effects of mutations. Results compared favorably with those of two widely used computational predictors. In vitro characterization of 80 single, nonactive-site mutants of CcdB showed that activity in vivo correlates moderately with thermal stability and solubility. The inability to refold reversibly, as well as a decreased folding rate in vitro, is associated with decreased activity in vivo. Upon probing the effect of modulating expression of various proteases and chaperones on mutant phenotypes, most deleterious mutants showed an increased in vivo activity and solubility only upon over-expression of either Trigger factor or SecB ATP-independent chaperones. Collectively, these data suggest that folding kinetics rather than protein stability is the primary determinant of activity in vivo This study enhances our understanding of how mutations affect phenotype, as well as the ability to predict fitness effects of point mutations. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  16. Prion propagation in cells expressing PrP glycosylation mutants.

    Science.gov (United States)

    Salamat, Muhammad K; Dron, Michel; Chapuis, Jérôme; Langevin, Christelle; Laude, Hubert

    2011-04-01

    Infection by prions involves conversion of a host-encoded cell surface protein (PrP(C)) to a disease-related isoform (PrP(Sc)). PrP(C) carries two glycosylation sites variably occupied by complex N-glycans, which have been suggested by previous studies to influence the susceptibility to these diseases and to determine characteristics of prion strains. We used the Rov cell system, which is susceptible to sheep prions, to generate a series of PrP(C) glycosylation mutants with mutations at one or both attachment sites. We examined their subcellular trafficking and ability to convert into PrP(Sc) and to sustain stable prion propagation in the absence of wild-type PrP. The susceptibility to infection of mutants monoglycosylated at either site differed dramatically depending on the amino acid substitution. Aglycosylated double mutants showed overaccumulation in the Golgi compartment and failed to be infected. Introduction of an ectopic glycosylation site near the N terminus fully restored cell surface expression of PrP but not convertibility into PrP(Sc), while PrP(C) with three glycosylation sites conferred cell permissiveness to infection similarly to the wild type. In contrast, predominantly aglycosylated molecules with nonmutated N-glycosylation sequons, produced in cells expressing glycosylphosphatidylinositol-anchorless PrP(C), were able to form infectious PrP(Sc). Together our findings suggest that glycosylation is important for efficient trafficking of anchored PrP to the cell surface and sustained prion propagation. However, properly trafficked glycosylation mutants were not necessarily prone to conversion, thus making it difficult in such studies to discern whether the amino acid changes or glycan chain removal most influences the permissiveness to prion infection.

  17. A COMPARISON OF SEMANTIC SIMILARITY MODELS IN EVALUATING CONCEPT SIMILARITY

    Directory of Open Access Journals (Sweden)

    Q. X. Xu

    2012-08-01

    Full Text Available The semantic similarities are important in concept definition, recognition, categorization, interpretation, and integration. Many semantic similarity models have been established to evaluate semantic similarities of objects or/and concepts. To find out the suitability and performance of different models in evaluating concept similarities, we make a comparison of four main types of models in this paper: the geometric model, the feature model, the network model, and the transformational model. Fundamental principles and main characteristics of these models are introduced and compared firstly. Land use and land cover concepts of NLCD92 are employed as examples in the case study. The results demonstrate that correlations between these models are very high for a possible reason that all these models are designed to simulate the similarity judgement of human mind.

  18. Characterization of Brucella abortus mutant strain Δ22915, a potential vaccine candidate.

    Science.gov (United States)

    Bao, Yanqing; Tian, Mingxing; Li, Peng; Liu, Jiameng; Ding, Chan; Yu, Shengqing

    2017-04-04

    Brucellosis, caused by Brucella spp., is an important zoonosis worldwide. Vaccination is an effective strategy for protection against Brucella infection in livestock in developing countries and in wildlife in developed countries. However, current vaccine strains including S19 and RB51 are pathogenic to humans and pregnant animals, limiting their use. In this study, we constructed the Brucella abortus (B. abortus) S2308 mutant strain Δ22915, in which the putative lytic transglycosylase gene BAB_RS22915 was deleted. The biological properties of mutant strain Δ22915 were characterized and protection of mice against virulent S2308 challenge was evaluated. The mutant strain Δ22915 showed reduced survival within RAW264.7 cells and survival in vivo in mice. In addition, the mutant strain Δ22915 failed to escape fusion with lysosomes within host cells, and caused no observable pathological damage. RNA-seq analysis indicated that four genes associated with amino acid/nucleotide transport and metabolism were significantly upregulated in mutant strain Δ22915. Furthermore, inoculation of ∆22915 at 10 5 colony forming units induced effective host immune responses and long-term protection of BALB/c mice. Therefore, mutant strain ∆22915 could be used as a novel vaccine candidate in the future to protect animals against B. abortus infection.

  19. Mutant TDP-43 within motor neurons drives disease onset but not progression in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Ditsworth, Dara; Maldonado, Marcus; McAlonis-Downes, Melissa; Sun, Shuying; Seelman, Amanda; Drenner, Kevin; Arnold, Eveline; Ling, Shuo-Chien; Pizzo, Donald; Ravits, John; Cleveland, Don W; Da Cruz, Sandrine

    2017-06-01

    Mutations in TDP-43 cause amyotrophic lateral sclerosis (ALS), a fatal paralytic disease characterized by degeneration and premature death of motor neurons. The contribution of mutant TDP-43-mediated damage within motor neurons was evaluated using mice expressing a conditional allele of an ALS-causing TDP-43 mutant (Q331K) whose broad expression throughout the central nervous system mimics endogenous TDP-43. TDP-43 Q331K mice develop age- and mutant-dependent motor deficits from degeneration and death of motor neurons. Cre-recombinase-mediated excision of the TDP-43 Q331K gene from motor neurons is shown to delay onset of motor symptoms and appearance of TDP-43-mediated aberrant nuclear morphology, and abrogate subsequent death of motor neurons. However, reduction of mutant TDP-43 selectively in motor neurons did not prevent age-dependent degeneration of axons and neuromuscular junction loss, nor did it attenuate astrogliosis or microgliosis. Thus, disease mechanism is non-cell autonomous with mutant TDP-43 expressed in motor neurons determining disease onset but progression defined by mutant acting within other cell types.

  20. From one body mutant to one cell mutant. A progress of radiation breeding in crops

    International Nuclear Information System (INIS)

    Nagatomi, Shigeki

    1996-01-01

    An effective method was established to obtain non-chimeral mutants with wide spectrum of flower colors, regenerated from floral organs on which mutated sectors were come out on chronic irradiated plants. By this way, six mutant varieties of flower colors have been selected from one pink flower of chrysanthemum, and cultivated for cut-flower production. By the same method, 3 mutant varieties with small and spray type flowers were selected in Eustoma. Mutant varieties such as a rust disease resistant in sugarcane, 6 dwarfs in Cytisus and pure-white mushroom in velvet shank have been selected successively for short period. (J.P.N.)

  1. Renewing the Respect for Similarity

    Directory of Open Access Journals (Sweden)

    Shimon eEdelman

    2012-07-01

    Full Text Available In psychology, the concept of similarity has traditionally evoked a mixture of respect, stemmingfrom its ubiquity and intuitive appeal, and concern, due to its dependence on the framing of the problemat hand and on its context. We argue for a renewed focus on similarity as an explanatory concept, bysurveying established results and new developments in the theory and methods of similarity-preservingassociative lookup and dimensionality reduction — critical components of many cognitive functions, aswell as of intelligent data management in computer vision. We focus in particular on the growing familyof algorithms that support associative memory by performing hashing that respects local similarity, andon the uses of similarity in representing structured objects and scenes. Insofar as these similarity-basedideas and methods are useful in cognitive modeling and in AI applications, they should be included inthe core conceptual toolkit of computational neuroscience.

  2. Modified Starch of Sorghum Mutant Line Zh-30 For High Fiber Muffin Products

    International Nuclear Information System (INIS)

    Santosa, D. D. S; Human, S

    2009-01-01

    Sorghum mutant line Zh-30 is a breeding line developed at the Center for the Application of Isotope and Radiation Technology, BATAN by using mutation techniques. Gamma irradiation with the dose of 300 Gy was used to induce sorghum genetic variation. Through selection processes in several generations, the mutant line Zh-30 was identified to have better agronomic characteristics, better grain quality and higher grain yield than the original variety. Research on modified starch quality of this mutant line was done to identify its potential use in food industry. Functionality of pregelatinized, hydroxypropyl and crosslinked starch of this mutant line (Mutant TexInstant 30) has been studied for its use in high fiber muffin products. Characteristics of high fiber muffins containing 1.50; 3.50 and 5.50% of Mutant Tex-Instant 30 replacement levels to wheat flour were evaluated using both sensory panel and physical test methods. With regard to the sensory parameters, the high fiber muffins containing 1.50 - 5.50 % Mutant Tex-Instant 30 in general were not significantly different compared to the standard reference muffin. Results of physical evaluations showed that all Mutant Tex-Instant 30 containing products retained more moisture during baking than the standard reference. Tenderness of all products decreased at similar rate following 24 and 48 hr of room temperature storage and seven days at freezer temperature. These results suggested that sorghum mutant line Zh-30 starch could be modified and potentially used in food industry as a subtitute of wheat flour (author)

  3. Modified Starch of Sorghum Mutant Line Zh-30 for High Fiber Muffin Products

    Directory of Open Access Journals (Sweden)

    D.D.S. Santosa

    2009-01-01

    Full Text Available Sorghum mutant line Zh-30 is a breeding line developed at the Center for the Application of Isotope and Radiation Technology, BATAN by using mutation techniques. Gamma irradiation with the dose of 300 Gy was used to induce sorghum genetic variation. Through selection processes in several generations, the mutant line Zh-30 was identified to have better agronomic characteristics, better grain quality and higher grain yield than the original variety. Research on modified starch quality of this mutant line was done to identify its potential use in food industry. Functionality of pregelatinized, hydroxypropyl and crosslinked starch of this mutant line (Mutant TexInstant 30 has been studied for its use in high fiber muffin products. Characteristics of high fiber muffins containing 1.50; 3.50 and 5.50% of Mutant Tex-Instant 30 replacement levels to wheat flour were evaluated using both sensory panel and physical test methods. With regard to the sensory parameters, the high fiber muffins containing 1.50 - 5.50 % Mutant Tex-Instant 30 in general were not significantly different compared to the standard reference muffin. Results of physical evaluations showed that all Mutant Tex-Instant 30 containing products retained more moisture during baking than the standard reference. Tenderness of all products decreased at similar rate following 24 and 48 hr of room temperature storage and seven days at freezer temperature. These results suggested that sorghum mutant line Zh-30 starch could be modified and potentially used in food industry as a subtitute of wheat flour.

  4. Mig6 Puts the Brakes on Mutant EGFR-Driven Lung Cancer | Center for Cancer Research

    Science.gov (United States)

    Lung cancer is the most common cause of cancer-related death worldwide. These cancers are often induced by mutations in the epidermal growth factor receptor (EGFR), resulting in constitutive activation of the protein’s tyrosine kinase domain. Lung cancers expressing these EGFR mutants are initially sensitive to tyrosine kinase inhibitors (TKIs), such as erlotinib, but often become resistant by developing compensatory mutations in EGFR or other growth-promoting pathways. To better understand how mutant EGFR initiates and maintains tumor growth in the hopes of identifying novel targets for drug development, Udayan Guha, M.D., Ph.D., of CCR’s Thoracic and Gastrointestinal Oncology Branch, and his colleagues examined the landscape of proteins phosphorylated in EGFR wild type and mutant cells. One protein hyper-phosphorylated in mutant EGFR cells was Mig6, a putative tumor suppressor.

  5. ALS-associated mutant FUS induces selective motor neuron degeneration through toxic gain of function.

    Science.gov (United States)

    Sharma, Aarti; Lyashchenko, Alexander K; Lu, Lei; Nasrabady, Sara Ebrahimi; Elmaleh, Margot; Mendelsohn, Monica; Nemes, Adriana; Tapia, Juan Carlos; Mentis, George Z; Shneider, Neil A

    2016-02-04

    Mutations in FUS cause amyotrophic lateral sclerosis (ALS), including some of the most aggressive, juvenile-onset forms of the disease. FUS loss-of-function and toxic gain-of-function mechanisms have been proposed to explain how mutant FUS leads to motor neuron degeneration, but neither has been firmly established in the pathogenesis of ALS. Here we characterize a series of transgenic FUS mouse lines that manifest progressive, mutant-dependent motor neuron degeneration preceded by early, structural and functional abnormalities at the neuromuscular junction. A novel, conditional FUS knockout mutant reveals that postnatal elimination of FUS has no effect on motor neuron survival or function. Moreover, endogenous FUS does not contribute to the onset of the ALS phenotype induced by mutant FUS. These findings demonstrate that FUS-dependent motor degeneration is not due to loss of FUS function, but to the gain of toxic properties conferred by ALS mutations.

  6. Modeling the dual pacemaker system of the tau mutant hamster.

    Science.gov (United States)

    Oda, G A; Menaker, M; Friesen, W O

    2000-06-01

    Circadian pacemakers in many animals are compound. In rodents, a two-oscillator model of the pacemaker composed of an evening (E) and a morning (M) oscillator has been proposed based on the phenomenon of "splitting" and bimodal activity peaks. The authors describe computer simulations of the pacemaker in tau mutant hamsters viewed as a system of mutually coupled E and M oscillators. These mutant animals exhibit normal type 1 PRCs when released into DD but make a transition to a type 0 PRC when held for many weeks in DD. The two-oscillator model describes particularly well some recent behavioral experiments on these hamsters. The authors sought to determine the relationships between oscillator amplitude, period, PRC, and activity duration through computer simulations. Two complementary approaches proved useful for analyzing weakly coupled oscillator systems. The authors adopted a "distinct oscillators" view when considering the component E and M oscillators and a "system" view when considering the system as a whole. For strongly coupled systems, only the system view is appropriate. The simulations lead the authors to two primary conjectures: (1) the total amplitude of the pacemaker system in tau mutant hamsters is less than in the wild-type animals, and (2) the coupling between the unit E and M oscillators is weakened during continuous exposure of hamsters to DD. As coupling strength decreases, activity duration (alpha) increases due to a greater phase difference between E and M. At the same time, the total amplitude of the system decreases, causing an increase in observable PRC amplitudes. Reduced coupling also increases the relative autonomy of the unit oscillators. The relatively autonomous phase shifts of E and M oscillators can account for both immediate compression and expansion of activity bands in tau mutant and wild-type hamsters subjected to light pulses.

  7. Officially released mutant varieties in China

    International Nuclear Information System (INIS)

    Liu, L.; Van Zanten, L.; Shu, Q.Y.; Maluszynski, M.

    2004-01-01

    The use of mutation techniques for crop improvement in China has a long and well-established tradition of more than 50 years. As the result of intensive research in many institutes dealing with application of nuclear technologies more than 620 cultivars of 44 crop species have been released. Numerous mutant varieties have been grown on a large scale bringing significant economic impact, sustaining crop production and greatly contributing to increase of food production also in stress prone areas of the country. However, there is still missing information not only on the number of mutant varieties released in particular crop species but also on mutagens applied, selection approaches and on the use of mutants in cross breeding. Numerous Chinese scientists collected and systematized this information. Results of their work were often published in local scientific journals in the Chinese language and as such were unavailable to breeders from other countries. Having this in mind, we requested Dr. Liu Luxiang, the Director of the Department of Plant Mutation Breeding and Genetics, Institute for Application of Atomic Energy, Chinese Academy of Agricultural Sciences in Beijing to help us in finding as much information as possible on mutant varieties officially released in China. The data has been collected in close collaboration with his colleagues from various institutions all over the country and then evaluated, edited and prepared for publication by our team responsible for the FAO/IAEA Database of Officially Released Mutant Varieties. We would like to thank all Chinese colleagues who contributed to this list of Chinese mutant varieties. We hope that this publication will stimulate plant breeders in China to collect more information on released mutant varieties and especially on the use of mutated genes in cross breeding. (author)

  8. Development of high yielding mutants in lentil

    International Nuclear Information System (INIS)

    Rajput, M.A.; Sarwar, G.; Siddiqui, K.A.

    2001-01-01

    Full text: Lentil (Lens culinaris Medik.) locally known as Masoor, is the second most important rabi pulse crop, after chickpea, in Pakistan. It is cultivated on an area of over 63,400 ha, which constitutes about 4.83% of the total area under pulses. The annual production of the crop is 28,200 tones with an average yield of 445 kg/ha. Yield at the national level is very low, about one-half of the world's yield, which is mainly due to non-availability of high yield potential genotypes. Keeping in view the importance of mutants in developing a large number of new varieties, an induced mutations programme was initiated at AEARC, Tandojam during 1987-88, to develop high yielding varieties in lentil. For this, seeds of two lentil varieties, 'Masoor-85' and 'ICARDA-8' had been irradiated with gamma-rays ranging from 100-600 Gy in NIAB, Faisalabad during 1990. Selections were made in M2 on the basis of earliness, plant height, branches/plant and 100 grain weight. After confirming these mutants in M3 they were promoted in station yield trials and studied continuously for three consecutive years (1993- 1995). Overall results revealed that these mutants have consistent improvement of earliness in flowering and maturity. Plant height also increased in all mutant lines except AEL 23/40/91 where reduction in this attribute was observed as compared to parent variety. Mutant lines AEL 49/20/91 and AEL 13/30/91 showed improvement in 100 grain weight. The improvement of some agronomic characters enhanced the yield of mutant lines in comparison to parent varieties (Masoor-85 and ICARDA-8). The diversity in yield over the respective parents was computed from 6.94 to 60.12%. From these encouraging results it is hoped that mutant lines like AEL 12/30/91 and AEL 49/20/91 may serve as potential lentil genotypes in future. (author)

  9. Isolation of a novel mutant gene for soil-surface rooting in rice (Oryza sativa L.).

    Science.gov (United States)

    Hanzawa, Eiko; Sasaki, Kazuhiro; Nagai, Shinsei; Obara, Mitsuhiro; Fukuta, Yoshimichi; Uga, Yusaku; Miyao, Akio; Hirochika, Hirohiko; Higashitani, Atsushi; Maekawa, Masahiko; Sato, Tadashi

    2013-11-20

    Root system architecture is an important trait affecting the uptake of nutrients and water by crops. Shallower root systems preferentially take up nutrients from the topsoil and help avoid unfavorable environments in deeper soil layers. We have found a soil-surface rooting mutant from an M2 population that was regenerated from seed calli of a japonica rice cultivar, Nipponbare. In this study, we examined the genetic and physiological characteristics of this mutant. The primary roots of the mutant showed no gravitropic response from the seedling stage on, whereas the gravitropic response of the shoots was normal. Segregation analyses by using an F2 population derived from a cross between the soil-surface rooting mutant and wild-type Nipponbare indicated that the trait was controlled by a single recessive gene, designated as sor1. Fine mapping by using an F2 population derived from a cross between the mutant and an indica rice cultivar, Kasalath, revealed that sor1 was located within a 136-kb region between the simple sequence repeat markers RM16254 and 2935-6 on the terminal region of the short arm of chromosome 4, where 13 putative open reading frames (ORFs) were found. We sequenced these ORFs and detected a 33-bp deletion in one of them, Os04g0101800. Transgenic plants of the mutant transformed with the genomic fragment carrying the Os04g0101800 sequence from Nipponbare showed normal gravitropic responses and no soil-surface rooting. These results suggest that sor1, a rice mutant causing soil-surface rooting and altered root gravitropic response, is allelic to Os04g0101800, and that a 33-bp deletion in the coding region of this gene causes the mutant phenotypes.

  10. Self-similar cosmological models

    Energy Technology Data Exchange (ETDEWEB)

    Chao, W Z [Cambridge Univ. (UK). Dept. of Applied Mathematics and Theoretical Physics

    1981-07-01

    The kinematics and dynamics of self-similar cosmological models are discussed. The degrees of freedom of the solutions of Einstein's equations for different types of models are listed. The relation between kinematic quantities and the classifications of the self-similarity group is examined. All dust local rotational symmetry models have been found.

  11. Self-similar factor approximants

    International Nuclear Information System (INIS)

    Gluzman, S.; Yukalov, V.I.; Sornette, D.

    2003-01-01

    The problem of reconstructing functions from their asymptotic expansions in powers of a small variable is addressed by deriving an improved type of approximants. The derivation is based on the self-similar approximation theory, which presents the passage from one approximant to another as the motion realized by a dynamical system with the property of group self-similarity. The derived approximants, because of their form, are called self-similar factor approximants. These complement the obtained earlier self-similar exponential approximants and self-similar root approximants. The specific feature of self-similar factor approximants is that their control functions, providing convergence of the computational algorithm, are completely defined from the accuracy-through-order conditions. These approximants contain the Pade approximants as a particular case, and in some limit they can be reduced to the self-similar exponential approximants previously introduced by two of us. It is proved that the self-similar factor approximants are able to reproduce exactly a wide class of functions, which include a variety of nonalgebraic functions. For other functions, not pertaining to this exactly reproducible class, the factor approximants provide very accurate approximations, whose accuracy surpasses significantly that of the most accurate Pade approximants. This is illustrated by a number of examples showing the generality and accuracy of the factor approximants even when conventional techniques meet serious difficulties

  12. Dynamic similarity in erosional processes

    Science.gov (United States)

    Scheidegger, A.E.

    1963-01-01

    A study is made of the dynamic similarity conditions obtaining in a variety of erosional processes. The pertinent equations for each type of process are written in dimensionless form; the similarity conditions can then easily be deduced. The processes treated are: raindrop action, slope evolution and river erosion. ?? 1963 Istituto Geofisico Italiano.

  13. Personalized recommendation with corrected similarity

    International Nuclear Information System (INIS)

    Zhu, Xuzhen; Tian, Hui; Cai, Shimin

    2014-01-01

    Personalized recommendation has attracted a surge of interdisciplinary research. Especially, similarity-based methods in applications of real recommendation systems have achieved great success. However, the computations of similarities are overestimated or underestimated, in particular because of the defective strategy of unidirectional similarity estimation. In this paper, we solve this drawback by leveraging mutual correction of forward and backward similarity estimations, and propose a new personalized recommendation index, i.e., corrected similarity based inference (CSI). Through extensive experiments on four benchmark datasets, the results show a greater improvement of CSI in comparison with these mainstream baselines. And a detailed analysis is presented to unveil and understand the origin of such difference between CSI and mainstream indices. (paper)

  14. Towards Personalized Medicine: Leveraging Patient Similarity and Drug Similarity Analytics

    Science.gov (United States)

    Zhang, Ping; Wang, Fei; Hu, Jianying; Sorrentino, Robert

    2014-01-01

    The rapid adoption of electronic health records (EHR) provides a comprehensive source for exploratory and predictive analytic to support clinical decision-making. In this paper, we investigate how to utilize EHR to tailor treatments to individual patients based on their likelihood to respond to a therapy. We construct a heterogeneous graph which includes two domains (patients and drugs) and encodes three relationships (patient similarity, drug similarity, and patient-drug prior associations). We describe a novel approach for performing a label propagation procedure to spread the label information representing the effectiveness of different drugs for different patients over this heterogeneous graph. The proposed method has been applied on a real-world EHR dataset to help identify personalized treatments for hypercholesterolemia. The experimental results demonstrate the effectiveness of the approach and suggest that the combination of appropriate patient similarity and drug similarity analytics could lead to actionable insights for personalized medicine. Particularly, by leveraging drug similarity in combination with patient similarity, our method could perform well even on new or rarely used drugs for which there are few records of known past performance. PMID:25717413

  15. Structures of the G81A mutant form of the active chimera of (S)-mandelate dehydrogenase and its complex with two of its substrates

    Energy Technology Data Exchange (ETDEWEB)

    Sukumar, Narayanasami [NE-CAT and Department of Chemistry and Chemical Biology, Cornell University, Building 436E, Argonne National Laboratory, Argonne, IL 60439 (United States); Dewanti, Asteriani [Department of Chemistry and Physics, Western Carolina University, Cullowhee, NC 28723 (United States); Merli, Angelo; Rossi, Gian Luigi [Department of Biochemistry and Molecular Biology, University of Parma, Parma (Italy); Mitra, Bharati [Department of Biochemistry and Molecular Biology, School of Medicine, Wayne State University, Detroit, MI 48201 (United States); Mathews, F. Scott, E-mail: mathews@biochem.wustl.edu [Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St Louis, MO 63110 (United States); NE-CAT and Department of Chemistry and Chemical Biology, Cornell University, Building 436E, Argonne National Laboratory, Argonne, IL 60439 (United States)

    2009-06-01

    The crystal structure of the G81A mutant form of the chimera of (S)-mandelate dehydrogenase and of its complexes with two of its substrates reveal productive and non-productive modes of binding for the catalytic reaction. The structure also indicates the role of G81A in lowering the redox potential of the flavin co-factor leading to an ∼200-fold slower catalytic rate of substrate oxidation. (S)-Mandelate dehydrogenase (MDH) from Pseudomonas putida, a membrane-associated flavoenzyme, catalyzes the oxidation of (S)-mandelate to benzoylformate. Previously, the structure of a catalytically similar chimera, MDH-GOX2, rendered soluble by the replacement of its membrane-binding segment with the corresponding segment of glycolate oxidase (GOX), was determined and found to be highly similar to that of GOX except within the substituted segments. Subsequent attempts to cocrystallize MDH-GOX2 with substrate proved unsuccessful. However, the G81A mutants of MDH and of MDH-GOX2 displayed ∼100-fold lower reactivity with substrate and a modestly higher reactivity towards molecular oxygen. In order to understand the effect of the mutation and to identify the mode of substrate binding in MDH-GOX2, a crystallographic investigation of the G81A mutant of the MDH-GOX2 enzyme was initiated. The structures of ligand-free G81A mutant MDH-GOX2 and of its complexes with the substrates 2-hydroxyoctanoate and 2-hydroxy-3-indolelactate were determined at 1.6, 2.5 and 2.2 Å resolution, respectively. In the ligand-free G81A mutant protein, a sulfate anion previously found at the active site is displaced by the alanine side chain introduced by the mutation. 2-Hydroxyoctanoate binds in an apparently productive mode for subsequent reaction, while 2-hydroxy-3-indolelactate is bound to the enzyme in an apparently unproductive mode. The results of this investigation suggest that a lowering of the polarity of the flavin environment resulting from the displacement of nearby water molecules caused by

  16. The research progress on plant mutant germplasm resources in China

    International Nuclear Information System (INIS)

    He Cexi; Ji Linzhen; Zhao Shirong

    1991-07-01

    Mutants induced by nuclear radiation or other mutagens are new artificial germplasm resources. Some mutants have been applied in plant breeding and great achievements have been reached. The status and progress on the collection, identification and utilization of mutants in China are introduced. A proposal for developing mutant germplasm resources with good agronomic characters is suggested

  17. Heterozygous inactivation of tsc2 enhances tumorigenesis in p53 mutant zebrafish

    Directory of Open Access Journals (Sweden)

    Seok-Hyung Kim

    2013-07-01

    Tuberous sclerosis complex (TSC is a multi-organ disorder caused by mutations of the TSC1 or TSC2 genes. A key function of these genes is to inhibit mTORC1 (mechanistic target of rapamycin complex 1 kinase signaling. Cells deficient for TSC1 or TSC2 have increased mTORC1 signaling and give rise to benign tumors, although, as a rule, true malignancies are rarely seen. In contrast, other disorders with increased mTOR signaling typically have overt malignancies. A better understanding of genetic mechanisms that govern the transformation of benign cells to malignant ones is crucial to understand cancer pathogenesis. We generated a zebrafish model of TSC and cancer progression by placing a heterozygous mutation of the tsc2 gene in a p53 mutant background. Unlike tsc2 heterozygous mutant zebrafish, which never exhibited cancers, compound tsc2;p53 mutants had malignant tumors in multiple organs. Tumorigenesis was enhanced compared with p53 mutant zebrafish. p53 mutants also had increased mTORC1 signaling that was further enhanced in tsc2;p53 compound mutants. We found increased expression of Hif1-α, Hif2-α and Vegf-c in tsc2;p53 compound mutant zebrafish compared with p53 mutant zebrafish. Expression of these proteins probably underlies the increased angiogenesis seen in compound mutant zebrafish compared with p53 mutants and might further drive cancer progression. Treatment of p53 and compound mutant zebrafish with the mTORC1 inhibitor rapamycin caused rapid shrinkage of tumor size and decreased caliber of tumor-associated blood vessels. This is the first report using an animal model to show interactions between tsc2, mTORC1 and p53 during tumorigenesis. These results might explain why individuals with TSC rarely have malignant tumors, but also suggest that cancer arising in individuals without TSC might be influenced by the status of TSC1 and/or TSC2 mutations and be potentially treatable with mTORC1 inhibitors.

  18. Induction of mutagenized tomato populations for investigation on agronomic traits and mutant phenotyping

    Directory of Open Access Journals (Sweden)

    Rafiul Amin Laskar

    2018-01-01

    Full Text Available Global demand for tomato production increased tremendously due to its diverse utility in raw, cooked and processed form of food. This necessitates the continued supply of highly nutritious and better yielding improved cultivars to the producers, considering the rapid changing agro-climatic condition. In this study, induced mutant tomato populations of widely recommended tomato genotype Arka Vikas (Sel-22 were generated using chemical mutagen ethyl methane sulfonate (EMS, hydrazine hydrates (HZ and their combined treatments. In the in vitro study, a gradual reduction in germination percentage and seedling height occurred with the increasing concentrations of mutagens. Combination of EMS and HZ caused maximum biological inhibition followed by EMS and HZ treatments alone in M1 generation. The rate of survival and fertility in M1 plants of tomato was found highly affected due to mutagenic treatment, in which sensitivity toward combined treatment was found highest followed by EMS and HZ. Inspection on induced phenotypic variations in individual plants of M2 population resulted in identification and isolation of wide range of mutants with altered phenotypes. Highest mutation frequency was resulted by combined mutagens followed by the EMS and HZ treatment. Agronomic trait analyses showed intra and inter treatment variations in three quantitative traits (Plant height, fertile branch per plant and fruits per plant of M2 mutagenized population. Assessment on rate of mutant recovery in M2 population showed highest mutant recovery is possible with combination treatments and then 0.02% HZ followed by 0.02% EMS. In the present study, phenotyping of the mutants revealed that vegetative organs (‘plant size’, ‘plant habit’ and ‘leaf morphology’ was the most sensitive category (69.33% to which most of the mutant belongs, followed by ‘fruit color and size’ (20.27% and ‘germination’ (9.79%. Comparative investigation on number of mutants and

  19. Un Nuevo Enfoque en el Estudio de la Esporotricosis: Mutantes de Sporothrix schenckii

    Directory of Open Access Journals (Sweden)

    Haydee Torres-Guerrero

    2012-02-01

    Full Text Available Una cepa silvestre y cepas mutantes de Sporothrix schenckii, se han estudiado como un modelo experimental de los procesos de diferenciación y desarrollo que se presentan al ser invadidas las células huésped y causar la esporotricosis. Las cepas mutantes de S. schenckii fueron obtenidas por exposición a la luz ultravioleta y Nitrosoguanidina. Las mutantes morfológicas M-III y M-V fueron seleccionadas. Estas mutantes muestran una alteración colonial y un mayor desarrollo que las cepas silvestres. Además, las mutantes presentan mayor adhesión al sustrato. El análisis de componentes de la pared celular y la distribución de núcleos, indican que no existen diferencias significativas que implique un daño por la mutación. Los resultados indican que en las mutantes morfológicas existe una alteración en el patrón de crecimiento y su regulación. Son necesarios, estudios bioquímicos e inmunológicos, relacionados con la virulencia S. schenckii que puedan ser útiles en el diagnóstico y en un futuro contribuyan a medidas preventivas para la esporotricosis. A wild-type strain and mutant strain of Sporothrix schenckii were studied as an experimental model in the process of differentiation and development which occurs when the host cell is invaded causing sporotrichosis. The mutant strains of S. schenckii were obtained by exposure to ultraviolet light and Nitrosoguanidine. The morphological mutants M-III and M-V were selected. These mutants showed a colonial alteration and a higher growth rate than the wild-type strains. Moreover, the mutants showed greater adhesion to the substratum. An analysis of the components of the cell wall and the distribution of nuclei indicate that significant differences do not exist which involve damage by mutation. The results suggest that in morphological mutants there is an alteration of growth and its regulation in the host cell. Biochemical and immunological studies related to the virulence of S. schenkii are

  20. Hepatitis B surface gene 145 mutant as a minor population in hepatitis B virus carriers

    Directory of Open Access Journals (Sweden)

    Komatsu Haruki

    2012-01-01

    Full Text Available Abstract Background Hepatitis B virus (HBV can have mutations that include the a determinant, which causes breakthrough infection. In particular, a single mutation at amino acid 145 of the surface protein (G145 is frequently reported in the failure of prophylactic treatment. The aim of this study was to evaluate the frequency of the a determinant mutants, especially the G145 variant, in Japan, where universal vaccination has not been adopted. Methods The present study was a retrospective study. The study cohorts were defined as follows: group 1, children with failure to prevent mother-to-child transmission despite immunoprophylaxis (n = 18, male/female = 8/10, age 1-14 years; median 6 years; group 2, HBV carriers who had not received vaccination or hepatitis B immunoglobulin (n = 107, male/female = 107, age 1-52 years; median 16 years. To detect the G145R and G145A mutants in patients, we designed 3 probes for real-time PCR. We also performed direct sequencing and cloning of PCR products. Results By mutant-specific real-time PCR, one subject (5.6% was positive for the G145R mutant in group 1, while the G145 mutant was undetectable in group 2. The a determinant mutants were detected in one (5.6% of the group 1 subjects and 10 (9.3% of the group 2 subjects using direct sequencing, but direct sequencing did not reveal the G145 mutant as a predominant strain in the two groups. However, the subject who was positive according to the mutant-specific real-time PCR in group 1 had overlapped peaks at nt 587 in the electropherogram. In group 2, 11 patients had overlapped peaks at nt 587 in the electropherogram. Cloning of PCR products allowed detection of the G145R mutant as a minor strain in 7 (group 1: 1 subject, group 2: 6 subjects of 12 subjects who had overlapped peaks at nt 587 in the electropherogram. Conclusions The frequency of the a determinant mutants was not high in Japan. However, the G145R mutant was often present as a minor population in

  1. Homologous series of induced early mutants in Indica rice. Pt.3: The relationship between the induction of homologous series of early mutants and its different pedigree

    International Nuclear Information System (INIS)

    Chen Xiulan; Yang Hefeng; He Zhentian; Han Yuepeng; Liu Xueyu

    2002-01-01

    The percentage of homologous series of early mutants (PHSEM) induced by irradiation was closely related to its pedigree. This study showed that PHSEM for varieties with the same pedigree were similar, and there were three different level of dominance (high, low and normal) in the homologous series induced from different pedigree. The PHSEM for varieties derived form distant-relative-parents were higher than that derived from close-relative-parents. There was the dominance pedigree for the induction of homologous series of early mutants. IR8(Peta x DGWG), IR127 (Cpslo x Sigadis) and IR24 (IR8 x IR127) were dominant pedigree, and varieties derived from them could be easily induced the homologous series of early mutants

  2. Delayed chromosomal instability caused by large deletion

    International Nuclear Information System (INIS)

    Ojima, M.; Suzuki, K.; Kodama, S.; Watanabe, M.

    2003-01-01

    Full text: There is accumulating evidence that genomic instability, manifested by the expression of delayed phenotypes, is induced by X-irradiation but not by ultraviolet (UV) light. It is well known that ionizing radiation, such as X-rays, induces DNA double strand breaks, but UV-light mainly causes base damage like pyrimidine dimers and (6-4) photoproducts. Although the mechanism of radiation-induced genomic instability has not been thoroughly explained, it is suggested that DNA double strand breaks contribute the induction of genomic instability. We examined here whether X-ray induced gene deletion at the hprt locus induces delayed instability in chromosome X. SV40-immortalized normal human fibroblasts, GM638, were irradiated with X-rays (3, 6 Gy), and the hprt mutants were isolated in the presence of 6-thioguanine (6-TG). A 2-fold and a 60-fold increase in mutation frequency were found by 3 Gy and 6 Gy irradiation, respectively. The molecular structure of the hprt mutations was determined by multiplex polymerase chain reaction of nine exons. Approximately 60% of 3 Gy mutants lost a part or the entire hprt gene, and the other mutants showed point mutations like spontaneous mutants. All 6 Gy mutants show total gene deletion. The chromosomes of the hprt mutants were analyzed by Whole Human Chromosome X Paint FISH or Xq telomere FISH. None of the point or partial gene deletion mutants showed aberrations of X-chromosome, however total gene deletion mutants induced translocations and dicentrics involving chromosome X. These results suggest that large deletion caused by DNA double strand breaks destabilizes chromosome structure, which may be involved in an induction of radiation-induced genomic instability

  3. A Transcriptomic Analysis of Xylan Mutants Does Not Support the Existence of a Secondary Cell Wall Integrity System in Arabidopsis.

    Science.gov (United States)

    Faria-Blanc, Nuno; Mortimer, Jenny C; Dupree, Paul

    2018-01-01

    Yeast have long been known to possess a cell wall integrity (CWI) system, and recently an analogous system has been described for the primary walls of plants (PCWI) that leads to changes in plant growth and cell wall composition. A similar system has been proposed to exist for secondary cell walls (SCWI). However, there is little data to support this. Here, we analyzed the stem transcriptome of a set of cell wall biosynthetic mutants in order to investigate whether cell wall damage, in this case caused by aberrant xylan synthesis, activates a signaling cascade or changes in cell wall synthesis gene expression. Our data revealed remarkably few changes to the transcriptome. We hypothesize that this is because cells undergoing secondary cell wall thickening have entered a committed programme leading to cell death, and therefore a SCWI system would have limited impact. The absence of transcriptomic responses to secondary cell wall alterations may facilitate engineering of the secondary cell wall of plants.

  4. Analysis of interactions of Salmonella type three secretion mutants with 3-D intestinal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Andrea L Radtke

    Full Text Available The prevailing paradigm of Salmonella enteropathogenesis based on monolayers asserts that Salmonella pathogenicity island-1 Type Three Secretion System (SPI-1 T3SS is required for bacterial invasion into intestinal epithelium. However, little is known about the role of SPI-1 in mediating gastrointestinal disease in humans. Recently, SPI-1 deficient nontyphoidal Salmonella strains were isolated from infected humans and animals, indicating that SPI-1 is not required to cause enteropathogenesis and demonstrating the need for more in vivo-like models. Here, we utilized a previously characterized 3-D organotypic model of human intestinal epithelium to elucidate the role of all characterized Salmonella enterica T3SSs. Similar to in vivo reports, the Salmonella SPI-1 T3SS was not required to invade 3-D intestinal cells. Additionally, Salmonella strains carrying single (SPI-1 or SPI-2, double (SPI-1/2 and complete T3SS knockout (SPI-1/SPI-2: flhDC also invaded 3-D intestinal cells to wildtype levels. Invasion of wildtype and TTSS mutants was a Salmonella active process, whereas non-invasive bacterial strains, bacterial size beads, and heat-killed Salmonella did not invade 3-D cells. Wildtype and T3SS mutants did not preferentially target different cell types identified within the 3-D intestinal aggregates, including M-cells/M-like cells, enterocytes, or Paneth cells. Moreover, each T3SS was necessary for substantial intracellular bacterial replication within 3-D cells. Collectively, these results indicate that T3SSs are dispensable for Salmonella invasion into highly differentiated 3-D models of human intestinal epithelial cells, but are required for intracellular bacterial growth, paralleling in vivo infection observations and demonstrating the utility of these models in predicting in vivo-like pathogenic mechanisms.

  5. Bacterio-opsin mutants of Halobacterium halobium

    Science.gov (United States)

    Betlach, Mary; Pfeifer, Felicitas; Friedman, James; Boyer, Herbert W.

    1983-01-01

    The bacterio-opsin (bop) gene of Halobacterium halobium R1 has been cloned with about 40 kilobases of flanking genomic sequence. The 40-kilobase segment is derived from the (G+C)-rich fraction of the chromosome and is not homologous to the major (pHH1) or minor endogenous covalently closed circular DNA species of H. halobium. A 5.1-kilobase Pst I fragment containing the bop gene was subcloned in pBR322 and a partial restriction map was determined. Defined restriction fragments of this clone were used as probes to analyze the defects associated with the bop gene in 12 bacterio-opsin mutants. Eleven out of 12 of the mutants examined had inserts ranging from 350 to 3,000 base pairs either in the bop gene or up to 1,400 base pairs upstream. The positions of the inserts were localized to four regions in the 5.1-kilobase genomic fragment: within the gene (one mutant), in a region that overlaps the 5′ end of the gene (seven mutants), and in two different upstream regions (three mutants). Two revertants of the mutant with the most distal insert had an additional insert in the same region. The polar effects of these inserts are discussed in terms of inactivation of a regulatory gene or disruption of part of a coordinately expressed operon. Given the defined nature of the bop mRNA—i.e., it has a 5′ leader sequence of three ribonucleotides—these observations indicate that the bop mRNA might be processed from a large mRNA transcript. Images PMID:16593291

  6. [Mutant prevention concentrations of antibacterial agents to ocular pathogenic bacteria].

    Science.gov (United States)

    Liang, Qing-Feng; Wang, Zhi-Qun; Li, Ran; Luo, Shi-Yun; Deng, Shi-Jing; Sun, Xu-Guang

    2009-01-01

    To establish a method to measure mutant prevention concentration (MPC) in vitro, and to measure MPC of antibacterial agents for ocular bacteria caused keratitis. It was an experimental study. Forty strains of ocular bacteria were separated from cornea in Beijing Institute of Ophthalmology, which included 8 strains of Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Pseudomonas aeruginosa and Klebsiella pneumoniae respectively. The minimal inhibitory concentration (MIC) of the levofloxacin (LVF), ofloxacin (OFL), ciprofloxacin (CIP), norfloxacin (NFL), tobramycin (TOB) and chloromycetin (CHL) were determined by agar dilution method from National Committee of Clinical Laboratory Standard (NCCLS). The MPC were measured by accumulate-bacterial methods with bacterial population inoculated more than 1.2 x 10(10) colony forming units per milliliter with Mueller-Hinton broth and tryptic soy agar plate. With the software of SPSS 11.0, the datum such as the range of MIC, MPC, MIC90 and MPC90 were calculated, and the selection index (MPC90/ MI90) and mutant selection window (MSW) were obtained. The MI90 of LVF and TOB (4 mg/L) to Staphylococcus aureus strains were the lowest. CIP showed the lowest MIC90 (0.25 mg/L) to Pseudomonas aeruginosa among six kinds of antibacterial agents. The MIC90 of LVF to Staphylococcus epidermidis (256 mg/L), Streptococcus pneumoniae (1 mg/L) and Klebsiella pneumoniae (0.25 mg/L) were lower than other antibacterial agents. The MPC90, MSW and the MPC90/MIC90 of levofloxacin showed lower values compared with other antibacterial medicines. From all the datum, the MIC90 of CHL was the highest and the activity was the weakest. Although the activity of LVF was higher to every kind of bacteria, CIP had the highest activity antibacterial to Pseudomonas aeruginosa. The capacity of CHL and TOB was weaker than Quinolones for restricting resistant mutants on ocular bacteria. LVF had the strongest capacity for restricting resistant

  7. Chlorophyll mutants in Phaseolus vulgaris (L.) Savi

    International Nuclear Information System (INIS)

    Svetleva, D.; Petkova, S.

    1991-01-01

    Three-year investigations were conducted on chlorophyll mutants of three type: viridissima, claroviridis, flavoviridis, viridocostata and xanthomarginata produced post gamma irradiation ( 60 Co, 8 krad, 280 rad/min). Cell division rate in spectrum and in quantity of induced aberrations was found to have no significant differences with the control. Chlorophyll mutations compared to the control are less developed and their productive characters are less manifested. Cell division rate and the quantity of induced aberrations have no relation to the elements of productivity in the mutants investigated. 3 tabs., 12 refs

  8. Alternating hemiplegia of childhood-related neural and behavioural phenotypes in Na+,K+-ATPase α3 missense mutant mice.

    Directory of Open Access Journals (Sweden)

    Greer S Kirshenbaum

    Full Text Available Missense mutations in ATP1A3 encoding Na(+,K(+-ATPase α3 have been identified as the primary cause of alternating hemiplegia of childhood (AHC, a motor disorder with onset typically before the age of 6 months. Affected children tend to be of short stature and can also have epilepsy, ataxia and learning disability. The Na(+,K(+-ATPase has a well-known role in maintaining electrochemical gradients across cell membranes, but our understanding of how the mutations cause AHC is limited. Myshkin mutant mice carry an amino acid change (I810N that affects the same position in Na(+,K(+-ATPase α3 as I810S found in AHC. Using molecular modelling, we show that the Myshkin and AHC mutations display similarly severe structural impacts on Na(+,K(+-ATPase α3, including upon the K(+ pore and predicted K(+ binding sites. Behavioural analysis of Myshkin mice revealed phenotypic abnormalities similar to symptoms of AHC, including motor dysfunction and cognitive impairment. 2-DG imaging of Myshkin mice identified compromised thalamocortical functioning that includes a deficit in frontal cortex functioning (hypofrontality, directly mirroring that reported in AHC, along with reduced thalamocortical functional connectivity. Our results thus provide validation for missense mutations in Na(+,K(+-ATPase α3 as a cause of AHC, and highlight Myshkin mice as a starting point for the exploration of disease mechanisms and novel treatments in AHC.

  9. Differential chromosomal and mitochondrial DNA synthesis in temperature-sensitive mutants of Ustilago maydis

    Energy Technology Data Exchange (ETDEWEB)

    Unrau, P.

    1977-01-01

    The amount and type of residual DNA synthesis was determined in eight temperature-sensitive mutants of the smut fungus Ustilago maydis after incubation at the restrictive temperature (32/sup 0/C) for eight hours. Mutants ts-220, ts-207, ts-432 and ts-346 were found to have an overall reduction in the synthesis of both nuclear and mitochondrial DNA in comparison to the wild-type. In mutants ts-20, tsd 1-1, ts-84 and pol 1-1 nuclear DNA synthesis was depressed relative to mitochondrial synthesis. The DNA-polymerase mutant pol 1-1 had persistent nuclear synthesis at about 50% of the rate of synthesis of mitochondrial DNA and similar behavior was observed in a diploid homozygous strain. Mutant ts-84 had an initial burst of DNA synthesis which was reduced for nuclear but not mitochondrial synthesis after three hours preincubation at 32/sup 0/C. tsd 1-1 and ts-20 had nuclear residual synthesis amounting to about 25% of the relative rate of mitochondrial synthesis which correlates to increasing UV sensitivity of these strains on incubation at 32/sup 0/C. A pol 1-1 ts-84 double mutant had an additive loss of nuclear DNA synthesis which indicates that the steps of replication involved may be sequential.

  10. Radiation-induced mutagenicity in repair deficient Chinese hamster ovary (CHO) mutants

    International Nuclear Information System (INIS)

    Tesmer, J.G.; Saunders, E.H.; Chen, D.J.

    1987-01-01

    To determine if there is a relationship between DNA double-strand break repair and mutagenicity the authors utilized two x-ray sensitive mutants of Chinese hamster ovary cells along with the parental line K1. The two mutant lines xrs-5 and xrs-6, which have different DSB repair capabilities, were used to determine cell killing and 6-thioguanine resistance (6TG/sup r/) mutation frequencies induced by either x-rays of α-particles, x-ray survival data indicated the two mutant lines have similar sensitivity and are 5-7 fold more sensitive than the parental line K1. The mutant lines are also sensitive to α-particles but to a lesser extent. The authors' 6TG mutation data indicated that the two mutant lines are hypermutable. When mutation frequencies were plotted against the log of survival, mutation frequency at a given survival level was greater in mutant cell population than in parental K1 cells. Their results support the notion that repair of DSB play an important role in the expression of radiation-induced cell killing and mutagenicity

  11. Bacillus subtilis mutants deficient in the adaptive response to simple alkylating agents

    Energy Technology Data Exchange (ETDEWEB)

    Morohoshi, F.; Munakata, N.

    1985-03-01

    Three mutant strains exhibiting hyper-sensitivity to N-methyl-N'-nitro-N-nitrosoguanidine, but not to methyl methanesulfonate, were selected by a replica method from mutagenized spores of Bacillus subtilis. All three were totally deficient in the adaptive response to N-methyl-N'-nitro-N-nitrosoguanidine with regard to both lethality and mutagenesis. The activity to destroy O/sup 6/-methylguanine residues in the methylated DNA was not elevated in the mutant cells by the pretreatment with sublethal concentrations of N-methyl-N-nitro-N-nitrosoguanidine. This deficiency corresponded to the persistance of O/sup 6/-methylguanine residues in the DNA of both control and pretreated mutant cells challenged with the drug. The lethal and mutagenic sensitivity of the mutant strains were observed only for methyl- or ethyl-nitroso compounds that are thought to be active as inducers and are also active in O-alkylation. Except for the insensitivity to methyl methanesulfonate, the phenotypes of these mutants look very similar to those of ada mutants isolated previously in Escherichia coli.

  12. Parallel analysis of tagged deletion mutants efficiently identifies genes involved in endoplasmic reticulum biogenesis.

    Science.gov (United States)

    Wright, Robin; Parrish, Mark L; Cadera, Emily; Larson, Lynnelle; Matson, Clinton K; Garrett-Engele, Philip; Armour, Chris; Lum, Pek Yee; Shoemaker, Daniel D

    2003-07-30

    Increased levels of HMG-CoA reductase induce cell type- and isozyme-specific proliferation of the endoplasmic reticulum. In yeast, the ER proliferations induced by Hmg1p consist of nuclear-associated stacks of smooth ER membranes known as karmellae. To identify genes required for karmellae assembly, we compared the composition of populations of homozygous diploid S. cerevisiae deletion mutants following 20 generations of growth with and without karmellae. Using an initial population of 1,557 deletion mutants, 120 potential mutants were identified as a result of three independent experiments. Each experiment produced a largely non-overlapping set of potential mutants, suggesting that differences in specific growth conditions could be used to maximize the comprehensiveness of similar parallel analysis screens. Only two genes, UBC7 and YAL011W, were identified in all three experiments. Subsequent analysis of individual mutant strains confirmed that each experiment was identifying valid mutations, based on the mutant's sensitivity to elevated HMG-CoA reductase and inability to assemble normal karmellae. The largest class of HMG-CoA reductase-sensitive mutations was a subset of genes that are involved in chromatin structure and transcriptional regulation, suggesting that karmellae assembly requires changes in transcription or that the presence of karmellae may interfere with normal transcriptional regulation. Copyright 2003 John Wiley & Sons, Ltd.

  13. Purification, gene cloning, gene expression, and mutants of Dps from the obligate anaerobe Porphyromonas gingivalis.

    Science.gov (United States)

    Ueshima, Junichi; Shoji, Mikio; Ratnayake, Dinath B; Abe, Kihachiro; Yoshida, Shinichi; Yamamoto, Kenji; Nakayama, Koji

    2003-03-01

    The periodontopathogen Porphyromonas gingivalis is an obligate anaerobe that is devoid of catalase but exhibits a relatively high degree of resistance to peroxide stress. In the present study, we demonstrate that P. gingivalis contains a Dps homologue that plays an important role in the protection of cells from peroxide stress. The Dps protein isolated from P. gingivalis displayed a ferritin-like spherical polymer consisting of 19-kDa subunits. Molecular cloning and sequencing of the gene encoding this protein revealed that it had a high similarity in nucleotide and amino acid sequences to Dps proteins from other species. The expression of Dps was significantly increased by exposure of P. gingivalis to atmospheric oxygen in an OxyR-dependent manner, indicating that it is regulated by the reactive oxygen species-regulating gene oxyR. The Dps-deficient mutants, including the dps single mutant and the ftn dps double mutant, showed no viability loss upon exposure to atmospheric oxygen for 6 h. In contrast to the wild type, however, these mutants exhibited the high susceptibility to hydrogen peroxide, thereby disrupting the viability. On the other hand, no significant difference in sensitivity to mitomycin C and metronidazole was observed between the wild type and the mutants. Furthermore, the dps single mutant, compared with the wild type, showed a lower viability in infected human umbilical vein endothelial cells.

  14. Interaction of a non-peptide agonist with angiotensin II AT1 receptor mutants

    DEFF Research Database (Denmark)

    Costa-Neto, Claudio M; Miyakawa, Ayumi A; Pesquero, João B

    2002-01-01

    and inositol phosphate turnover assays in COS-7 cells transiently transfected with the wild-type and mutant forms of the receptor. Mutant receptors bore modifications in the extracellular region: T88H, Y92H, G1961, G196W, and D278E. Compound L-162,313 displaced [125I]-Sar1,Leu8-AngII from the mutants G196I...... and G196W with IC50 values similar to that of the wild-type. The affinity was, however, slightly affected by the D278E mutation and more significantly by the T88H and Y92H mutations. In inositol phosphate turnover assays, the ability of L-162,313 to trigger the activation cascade was compared...... with that of angiotensin II. These assays showed that the G196W mutant reached a relative maximum activation exceeding that of the wild-type receptor; the efficacy was slightly reduced in the G1961 mutant and further reduced in the T88H, Y92H, and D278E mutants. Our data suggest that residues of the extracellular domain...

  15. Domain similarity based orthology detection.

    Science.gov (United States)

    Bitard-Feildel, Tristan; Kemena, Carsten; Greenwood, Jenny M; Bornberg-Bauer, Erich

    2015-05-13

    Orthologous protein detection software mostly uses pairwise comparisons of amino-acid sequences to assert whether two proteins are orthologous or not. Accordingly, when the number of sequences for comparison increases, the number of comparisons to compute grows in a quadratic order. A current challenge of bioinformatic research, especially when taking into account the increasing number of sequenced organisms available, is to make this ever-growing number of comparisons computationally feasible in a reasonable amount of time. We propose to speed up the detection of orthologous proteins by using strings of domains to characterize the proteins. We present two new protein similarity measures, a cosine and a maximal weight matching score based on domain content similarity, and new software, named porthoDom. The qualities of the cosine and the maximal weight matching similarity measures are compared against curated datasets. The measures show that domain content similarities are able to correctly group proteins into their families. Accordingly, the cosine similarity measure is used inside porthoDom, the wrapper developed for proteinortho. porthoDom makes use of domain content similarity measures to group proteins together before searching for orthologs. By using domains instead of amino acid sequences, the reduction of the search space decreases the computational complexity of an all-against-all sequence comparison. We demonstrate that representing and comparing proteins as strings of discrete domains, i.e. as a concatenation of their unique identifiers, allows a drastic simplification of search space. porthoDom has the advantage of speeding up orthology detection while maintaining a degree of accuracy similar to proteinortho. The implementation of porthoDom is released using python and C++ languages and is available under the GNU GPL licence 3 at http://www.bornberglab.org/pages/porthoda .

  16. Cell lines derived from a Medaka radiation-sensitive mutant have defects in DNA double-strand break responses

    International Nuclear Information System (INIS)

    Hidaka, Masayuki; Oda, Shoji; Mitani, Hiroshi; Kuwahara, Yoshikazu; Fukumoto, Manabu

    2010-01-01

    It was reported that the radiation-sensitive Medaka mutant 'ric1' has a defect in the repair of DNA double-strand breaks (DSBs) induced by γ-rays during early embryogenesis. To study the cellular response of a ric1 mutant to ionizing radiation (IR), we established the mutant embryonic cell lines RIC1-e9, RIC1-e42, RIC1-e43. Following exposure to γ-irradiation, the DSBs in wild-type cells were repaired within 1 h, while those in RIC1 cells were not rejoined even after 2 h. Cell death was induced in the wild-type cells with cell fragmentation, but only a small proportion of the RIC1 cells underwent cell death, and without cell fragmentation. Although both wild-type and RIC1 cells showed mitotic inhibition immediately after γ-irradiation, cell division was much slower to resume in the wild-type cells (20 h versus 12 h). In both wild-type and RIC1 cells, Ser139 phosphorylated H2AX (γH2AX) foci were formed after γ-irradiation, however, the γH2AX foci disappeared more quickly in the RIC1 cell lines. These results suggest that the instability of γH2AX foci in RIC1 cells cause an aberration of the DNA damage response. As RIC1 cultured cells showed similar defective DNA repair as ric1 embryos and RIC1 cells revealed defective cell death and cell cycle checkpoint, they are useful for investigating DNA damage responses in vitro. (author)

  17. Metabolite Profiling to Characterize Disease-related Bacteria GLUCONATE EXCRETION BY PSEUDOMONAS AERUGINOSA MUTANTS AND CLINICAL ISOLATES FROM CYSTIC FIBROSIS PATIENTS

    OpenAIRE

    Behrends, V; Bell, TJ; Liebeke, M; Cordes-Blauert, A; Ashraf, SN; Nair, C; Zlosnik, JEA; Williams, HD; Bundy, JG

    2013-01-01

    Metabolic footprinting of supernatants has been proposed as a tool for assigning gene function. We used NMR spectroscopy to measure the exometabolome of 86 single-gene transposon insertion mutant strains (mutants from central carbon metabolism and regulatory mutants) of the opportunistic pathogen Pseudomonas aeruginosa, grown on a medium designed to represent the nutritional content of cystic fibrosis sputum. Functionally related genes had similar metabolic profiles. E.g. for two-component sy...

  18. Defective DNA cross-link removal in Chinese hamster cell mutants hypersensitive to bifunctional alkylating agents

    International Nuclear Information System (INIS)

    Hoy, C.A.; Thompson, L.H.; Mooney, C.L.; Salazar, E.P.

    1985-01-01

    DNA repair-deficient mutants from five genetic complementation groups isolated previously from Chinese hamster cells were assayed for survival after exposure to the bifunctional alkylating agents mitomycin C or diepoxybutane. Groups 1, 3, and 5 exhibited 1.6- to 3-fold hypersensitivity compared to the wild-type cells, whereas Groups 2 and 4 exhibited extraordinary hypersensitivity. Mutants from Groups 1 and 2 were exposed to 22 other bifunctional alkylating agents in a rapid assay that compared cytotoxicity of the mutants to the wild-type parental strain, AA8. With all but two of the compounds, the Group 2 mutant (UV4) was 15- to 60-fold more sensitive than AA8 or the Group 1 mutant (UV5). UV4 showed only 6-fold hypersensitivity to quinacrine mustard. Alkaline elution measurements showed that this compound produced few DNA interstrand cross-links but numerous strand breaks. Therefore, the extreme hypersensitivity of mutants from Groups 2 and 4 appeared specific for compounds the main cytotoxic lesions of which were DNA cross-links. Mutant UV5 was only 1- to 4-fold hypersensitive to all the compounds. Although the initial number of cross-links was similar for the three cell lines, the efficiency of removal of cross-links was lowest in UV4 and intermediate in UV5. These results suggest that the different levels of sensitivity are specifically related to different efficiencies of DNA cross-link removal. The phenotype of hypersensitivity to both UV radiation and cross-link damage exhibited by the mutants in Groups 2 and 4 appears to differ from those of the known human DNA repair syndromes

  19. Generation of a Mutant Mucor hiemalis Endoglycosidase That Acts on Core-fucosylated N-Glycans.

    Science.gov (United States)

    Katoh, Toshihiko; Katayama, Takane; Tomabechi, Yusuke; Nishikawa, Yoshihide; Kumada, Jyunichi; Matsuzaki, Yuji; Yamamoto, Kenji

    2016-10-28

    Endo-β-N-acetylglucosaminidase M (Endo-M), an endoglycosidase from the fungus Mucor hiemalis, is a useful tool for chemoenzymatic synthesis of glycoconjugates, including glycoprotein-based therapeutics having a precisely defined glycoform, by virtue of its transglycosylation activity. Although Endo-M has been known to act on various N-glycans, it does not act on core-fucosylated N-glycans, which exist widely in mammalian glycoproteins, thus limiting its application. Therefore, we performed site-directed mutagenesis on Endo-M to isolate mutant enzymes that are able to act on mammalian-type core-α1,6-fucosylated glycans. Among the Endo-M mutant enzymes generated, those in which the tryptophan at position 251 was substituted with alanine or asparagine showed altered substrate specificities. Such mutant enzymes exhibited increased hydrolysis of a synthetic α1,6-fucosylated trimannosyl core structure, whereas their activity on the afucosylated form decreased. In addition, among the Trp-251 mutants, the W251N mutant was most efficient in hydrolyzing the core-fucosylated substrate. W251N mutants could act on the immunoglobulin G-derived core-fucosylated glycopeptides and human lactoferrin glycoproteins. This mutant was also capable of transferring the sialyl glycan from an activated substrate intermediate (sialyl glyco-oxazoline) onto an α1,6-fucosyl-N-acetylglucosaminyl biotin. Furthermore, the W251N mutant gained a glycosynthase-like activity when a N175Q substitution was introduced and it caused accumulation of the transglycosylation products. These findings not only give insights into the substrate recognition mechanism of glycoside hydrolase family 85 enzymes but also widen their scope of application in preparing homogeneous glycoforms of core-fucosylated glycoproteins for the production of potent glycoprotein-based therapeutics. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. Similarity measures for face recognition

    CERN Document Server

    Vezzetti, Enrico

    2015-01-01

    Face recognition has several applications, including security, such as (authentication and identification of device users and criminal suspects), and in medicine (corrective surgery and diagnosis). Facial recognition programs rely on algorithms that can compare and compute the similarity between two sets of images. This eBook explains some of the similarity measures used in facial recognition systems in a single volume. Readers will learn about various measures including Minkowski distances, Mahalanobis distances, Hansdorff distances, cosine-based distances, among other methods. The book also summarizes errors that may occur in face recognition methods. Computer scientists "facing face" and looking to select and test different methods of computing similarities will benefit from this book. The book is also useful tool for students undertaking computer vision courses.

  1. Cell-cycle kinetics and ultraviolet light survival in UV-1, a Chinese hamster ovary cell mutant defective in post-replication recovery

    International Nuclear Information System (INIS)

    Collins, A.

    1982-01-01

    UV-I, an ultraviolet-sensitive mutant of CHO-KI, is abnormally slow to recover from the inhibition of DNA synthesis caused by u.v. irradiation. When synchronized UV-I cells are irradiated in G 1 , their movement into S phase is unaltered, but thymidine incorporation is depressed. When irradiated in S phase, again incorporation is more depressed, and S phase suffers a greater delay in UV-I than in the parent cell. UV-I and its parent have similar capacities for excision repair of u.v.-induced damage inflicted in G 1 , and so enter S phase with similar amounts of unrepaired damage. The single-cell survival was measured after irradiation at different points in the cell cycle. The mutant and parent cells have similar values of D 0 (mean lethal dose) except in mitosis, when the parent cell shows markedly greater resistance to u.v. irradiation. Dsub(q) (quasi-threshold dose) is fairly constant for the parent cell, but in UV-I it falls to a minimum in S phase. The responses of UV-I to u.v. irradiation are generally consistent with its known defect in post-replication recovery, i.e. the ability to join up the abnormally small DNA fragments synthesized on a u.v.-damaged template. (author)

  2. E2-EPF UCP regulates stability and functions of missense mutant pVHL via ubiquitin mediated proteolysis.

    Science.gov (United States)

    Park, Kyeong-Su; Kim, Ju Hee; Shin, Hee Won; Chung, Kyung-Sook; Im, Dong-Soo; Lim, Jung Hwa; Jung, Cho-Rok

    2015-10-26

    Missense mutation of VHL gene is frequently detected in type 2 VHL diseases and linked to a wide range of pVHL functions and stability. Certain mutant pVHLs retain ability to regulate HIFs but lose their function by instability. In this case, regulating of degradation of mutant pVHLs, can be postulated as therapeutic method. The stability and cellular function of missense mutant pVHLs were determine in HEK293T transient expressing cell and 786-O stable cell line. Ubiquitination assay of mutant VHL proteins was performed in vitro system. Anticancer effect of adenovirus mediated shUCP expressing was evaluated using ex vivo mouse xenograft assay. Three VHL missense mutants (V155A, L158Q, and Q164R) are directly ubiquitinated by E2-EPF UCP (UCP) in vitro. Mutant pVHLs are more unstable than wild type in cell. Missense mutant pVHLs interact with UCP directly in both in vitro and cellular systems. Lacking all of lysine residues of pVHL result in resistance to ubiquitination thereby increase its stability. Missense mutant pVHLs maintained the function of E3 ligase to ubiquitinate HIF-1α in vitro. In cells expressing mutant pVHLs, Glut-1 and VEGF were relatively upregulated compared to their levels in cells expressing wild-type. Depletion of UCP restored missense mutant pVHLs levels and inhibited cell growth. Adenovirus-mediated shUCP RNA delivery inhibited tumor growth in ex vivo mouse xenograft model. These data suggest that targeting of UCP can be one of therapeutic method in type 2 VHL disease caused by unstable but functional missense mutant pVHL.

  3. Ethanol production using engineered mutant E. coli

    Science.gov (United States)

    Ingram, Lonnie O.; Clark, David P.

    1991-01-01

    The subject invention concerns novel means and materials for producing ethanol as a fermentation product. Mutant E. coli are transformed with a gene coding for pyruvate decarboxylase activity. The resulting system is capable of producing relatively large amounts of ethanol from a variety of biomass sources.

  4. Induced mutants for cereal grain protein improvement

    International Nuclear Information System (INIS)

    1982-01-01

    Out of 17 papers and one summary presented, six dealing with the genetic improvement of seed protein using ionizing radiations fall within the INIS subject scope. Other topics discussed were non-radiation induced mutants used for cereal grain protein improvement

  5. Male sterile mutant in Vigna radiata

    International Nuclear Information System (INIS)

    Pande, Kalpana; Raghuvanshi, S.S.

    1987-01-01

    Single and combined treatment of γ-rays and 0.25 per cent EMS were tried on Vigna radiata variety K851. A male sterile mutant was isolated in M 2 generation. Experiments indicated male sterility to be recessive and monogenic in nature. 6 figures. (author)

  6. Antimycin-insensitive mutants of Candida utilis II. The effects of antimycin on Cytochrome b

    DEFF Research Database (Denmark)

    Grimmelikhuijzen, C J; Marres, C A; Slater, Conor

    1975-01-01

    1. Cytochrome b-562 is more reduced in submitochondrial particles of mutant 28 during the aerobic steady-state respiration with succinate than in particles of the wild type. When anaerobiosis is reached, the reduction of cytochrome b is preceded by a rapid reoxidation in the mutnat. A similar reo...

  7. The cellular and molecular etiology of the craniofacial defects in the avian ciliopathic mutant talpid2

    Science.gov (United States)

    talpid2 is an avian autosomal recessive mutant with a myriad of congenital malformations, including polydactyly and facial clefting. Although phenotypically similar to talpid3, talpid2 has a distinct facial phenotype and an unknown cellular, molecular and genetic basis. We set out to determine the e...

  8. Construction and functional analysis of Trichoderma harzianum mutants that modulate maize resistance to the pathogen Curvularia lunata.

    Science.gov (United States)

    Fan, Lili; Fu, Kehe; Yu, Chuanjin; Ma, Jia; Li, Yaqian; Chen, Jie

    2014-01-01

    Agrobacterium tumefaciens-mediated transformation (ATMT) was used to generate an insertional mutant library of the mycelial fungus Trichoderma harzianum. From a total of 450 mutants, six mutants that showed significant influence on maize resistance to C. lunata were analyzed in detail. Maize coated with these mutants was more susceptible to C. lunata compared with those coated with a wild-type (WT) strain. Similar to other fungal ATMT libraries, all six mutants were single copy integrations, which occurred preferentially in noncoding regions (except two mutants) and were frequently accompanied by the loss of border sequences. Two mutants (T66 and T312) that were linked to resistance were characterized further. Maize seeds coated with T66 and T312 were more susceptible to C. lunata than those treated with WT. Moreover, the mutants affected the resistance of maize to C. lunata by enhancing jasmonate-responsive gene expression. T66 and T312 induced maize resistance to C. lunata infection through a jasmonic acid-dependent pathway.

  9. Isolation and partial characterization of a mutant of Bacillus thuringiensis producing melanin Isolamento e caracterização parcial de um mutante de Bacillus thuringiensis produtor de melanina

    Directory of Open Access Journals (Sweden)

    Gislayne T. Vilas-Bôas

    2005-09-01

    Full Text Available A mutant (407-P of Bacillus thuringiensis subsp. thuringiensis strain 407 producing a melanin was obtained after treatment with the mutagenic agent ethyl-methane-sulfonate. Several microbiological and biochemical properties of the two strains were analyzed and the results were similar. The mutant 407-P was also incorporated into non-sterilized soil samples, recovered, easily identified, and quantified, what enables its use in ecology of B. thuringiensis.Um mutante (407-P da linhagem Bacillus thuringiensis subsp. thuringiensis 407 produtor de melanina foi obtido após tratamento com o agente mutagênico etil-metano-sulfonato. Diversas propriedades microbiológicas e bioquímicas das duas linhagens foram analisadas e os resultados foram similares. O mutante 407-P foi incorporado em amostras de solo não esterilizado, recuperado, facilmente identificado e quantificado, possibilitando seu uso em estudos de ecologia de B. thuringiensis.

  10. A γA-Crystallin Mouse Mutant Secc with Small Eye, Cataract and Closed Eyelid.

    Directory of Open Access Journals (Sweden)

    Man Hei Cheng

    Full Text Available Cataract is the most common cause of visual loss in humans. A spontaneously occurred, autosomal dominant mouse mutant Secc, which displayed combined features of small eye, cataract and closed eyelid was discovered in our laboratory. In this study, we identified the mutation and characterized the cataract phenotype of this novel Secc mutant. The Secc mutant mice have eyelids that remain half-closed throughout their life. The mutant lens has a significant reduction in size and with opaque spots clustered in the centre. Histological analysis showed that in the core region of the mutant lens, the fiber cells were disorganized and clefts and vacuoles were observed. The cataract phenotype was evident from new born stage. We identified the Secc mutation by linkage analysis using whole genome microsatellite markers and SNP markers. The Secc locus was mapped at chromosome 1 flanked by SNPs rs3158129 and rs13475900. Based on the chromosomal position, the candidate cataract locus γ-crystallin gene cluster (Cryg was investigated by sequencing. A single base deletion (299delG in exon 3 of Cryga which led to a frame-shift of amino acid sequence from position 91 was identified. As a result of this mutation, the sequences of the 3rd and 4th Greek-key motifs of the γA-crystallin are replaced with an unrelated C-terminal peptide of 75 residues long. Coincidentally, the point mutation generated a HindIII restriction site, allowing the identification of the CrygaSecc mutant allele by RFLP. Western blot analysis of 3-week old lenses showed that the expression of γ-crystallins was reduced in the CrygaSecc mutant. Furthermore, in cell transfection assays using CrygaSecc mutant cDNA expression constructs in 293T, COS-7 and human lens epithelial B3 cell lines, the mutant γA-crystallins were enriched in the insoluble fractions and appeared as insoluble aggregates in the transfected cells. In conclusion, we have demonstrated that the Secc mutation leads to the

  11. Revisiting Inter-Genre Similarity

    DEFF Research Database (Denmark)

    Sturm, Bob L.; Gouyon, Fabien

    2013-01-01

    We revisit the idea of ``inter-genre similarity'' (IGS) for machine learning in general, and music genre recognition in particular. We show analytically that the probability of error for IGS is higher than naive Bayes classification with zero-one loss (NB). We show empirically that IGS does...... not perform well, even for data that satisfies all its assumptions....

  12. Fast business process similarity search

    NARCIS (Netherlands)

    Yan, Z.; Dijkman, R.M.; Grefen, P.W.P.J.

    2012-01-01

    Nowadays, it is common for organizations to maintain collections of hundreds or even thousands of business processes. Techniques exist to search through such a collection, for business process models that are similar to a given query model. However, those techniques compare the query model to each

  13. Glove boxes and similar containments

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    According to the present invention a glove box or similar containment is provided with an exhaust system including a vortex amplifier venting into the system, the vortex amplifier also having its main inlet in fluid flow connection with the containment and a control inlet in fluid flow connection with the atmosphere outside the containment. (U.S.)

  14. Nature of mutants induced by ionizing radiation in cultured hamster cells. II. Antigenic response and reverse mutation of HPRT-deficient mutants induced by. gamma. -rays or ethyl methanesulphonate

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R; Stretch, A; Thacker, J

    1986-04-01

    A large series of independent mutants deficient in HPRT enzyme activity, isolated from V79-4 hamster cells, were assessed for properties which reflect the nature of the genetic changes induced. A total of 88 mutants were screened, 43 isolated from ..gamma..-ray-treated cultures and 45 induced by ethyl methanesulphonate (EMS). Firstly, each mutant was assayed for the presence of protein with the antigenic response of HPRT. In a competitive inhibition assay, 31% of EMS-induced mutants were CRM-positive compared to 7% of the ..gamma..-ray series. Secondly, each mutant was tested for ability to revert to HPRT proficiency. All except 2 of the EMS-induced mutants reverted with ethyl nitrosourea ENU, and many reverted spontaneously, under the given conditions. However reversion was not detected in about 80% of ..gamma..-ray-induced mutants, suggesting that the types of forward mutation caused by ionizing radiation differ qualitatively from those caused by EMS. (Auth.). 30 refs.; 6 figs.; 2 tabs.

  15. Phanerochaete mutants with enhanced ligninolytic activity

    International Nuclear Information System (INIS)

    Kakar, S.N.; Perez, A.; Gonzales, J.

    1994-01-01

    In addition to lignin, the white rot fungus Phanerochaete chrysosporium has the ability to degrade a wide spectrum of recalcitrant organo pollutants in soils and aqueous media. Most of the organic compounds are degraded under ligninolytic conditions with the involvement of the extracellular enzymes, lignin peroxidases, and manganese-dependent peroxidases, which are produced as secondary metabolites triggered by conditions of nutrient starvation (e.g., nitrogen limitation). The fungus and its enzymes can thus provide alternative technologies for bioremediation, bio pulping, bio bleaching, and other industrial applications. The efficiency and effectiveness of the fungus can be enhanced by increasing production and secretion of the important enzymes in large quantities and as primary metabolites under enriched conditions. One way this can be achieved is through isolation of mutants that are deregulated, or are hyper producers or super secretors of key enzymes under enriched conditions. Through UV-light and γ-ray mutagenesis, we have isolated a variety of mutants, some of which produce key enzymes of the ligninolytic system under high-nitrogen growth conditions. One of the mutants, 76UV, produced 272 U of lignin peroxidases enzyme activity/L after 9 d under high nitrogen (although the parent strain does not produce this enzyme under these conditions). The mutant and the parent strains produced up to 54 and 62 U/L, respectively, of the enzyme activity under low nitrogen growth conditions during this period. In some experiments, the mutant showed 281 U/L of enzyme activity under high nitrogen after 17 d

  16. Genetic and systems level analysis of Drosophila sticky/citron kinase and dFmr1 mutants reveals common regulation of genetic networks

    Directory of Open Access Journals (Sweden)

    Zarnescu Daniela C

    2008-11-01

    Full Text Available Abstract Background In Drosophila, the genes sticky and dFmr1 have both been shown to regulate cytoskeletal dynamics and chromatin structure. These genes also genetically interact with Argonaute family microRNA regulators. Furthermore, in mammalian systems, both genes have been implicated in neuronal development. Given these genetic and functional similarities, we tested Drosophila sticky and dFmr1 for a genetic interaction and measured whole genome expression in both mutants to assess similarities in gene regulation. Results We found that sticky mutations can dominantly suppress a dFmr1 gain-of-function phenotype in the developing eye, while phenotypes produced by RNAi knock-down of sticky were enhanced by dFmr1 RNAi and a dFmr1 loss-of-function mutation. We also identified a large number of transcripts that were misexpressed in both mutants suggesting that sticky and dFmr1 gene products similarly regulate gene expression. By integrating gene expression data with a protein-protein interaction network, we found that mutations in sticky and dFmr1 resulted in misexpression of common gene networks, and consequently predicted additional specific phenotypes previously not known to be associated with either gene. Further phenotypic analyses validated these predictions. Conclusion These findings establish a functional link between two previously unrelated genes. Microarray analysis indicates that sticky and dFmr1 are both required for regulation of many developmental genes in a variety of cell types. The diversity of transcripts regulated by these two genes suggests a clear cause of the pleiotropy that sticky and dFmr1 mutants display and provides many novel, testable hypotheses about the functions of these genes. As both of these genes are implicated in the development and function of the mammalian brain, these results have relevance to human health as well as to understanding more general biological processes.

  17. Frequency of nuclear mutant huntingtin inclusion formation in neurons and glia is cell-type-specific

    NARCIS (Netherlands)

    Jansen, Anne H. P.; van Hal, Maurik; Op den Kelder, Ilse C.; Meier, Romy T.; de Ruiter, Anna-Aster; Schut, Menno H.; Smith, Donna L.; Grit, Corien; Brouwer, Nieske; Kamphuis, Willem; Boddeke, H. W. G. M.; den Dunnen, Wilfred F. A.; van Roon, Willeke M. C.; Bates, Gillian P.; Hol, Elly M.; Reits, Eric A.

    2017-01-01

    Huntington's disease (HD) is an autosomal dominant inherited neurodegenerative disorder that is caused by a CAG expansion in the Huntingtin (HTT) gene, leading to HTT inclusion formation in the brain. The mutant huntingtin protein (mHTT) is ubiquitously expressed and therefore nuclear inclusions

  18. Frequency of Nuclear Mutant Huntingtin Inclusion Formation in Neurons and Glia is Cell-Type-Specific

    NARCIS (Netherlands)

    Jansen, Anne H P; van Hal, Maurik; op den Kelder, Ilse C.; Meier, Romy T.; de Ruiter, Anna-Aster; Schut, Menno H.; Smith, Donna L.; Grit, Corien; Brouwer, Nieske; Kamphuis, Willem; Boddeke, H. W. G. M.; den Dunnen, Wilfred F. A.; van Roon, Willeke M. C.; Bates, Gillian P.; Hol, Elly M.; Reits, Eric A.

    Huntington's disease (HD) is an autosomal dominant inherited neurodegenerative disorder that is caused by a CAG expansion in the Huntingtin (HTT) gene, leading to HTT inclusion formation in the brain. The mutant huntingtin protein (mHTT) is ubiquitously expressed and therefore nuclear inclusions

  19. Characterization and increment of amylase production in mutant strains of Iranian native Bacillus licheniformis

    Directory of Open Access Journals (Sweden)

    Mohsen Mobini-Dehkordi

    2017-03-01

    Results: In this study, two interesting mutant strains were isolated and named B.L.2.M.1 and B.L.2.M.2. Mutations caused many changes in bacteria such as cell growth speed and enzyme production content. Differences in cell growth, production of amylase and other characters were significant at 0.05 level (Pvalue

  20. An Alfven eigenmode similarity experiment

    International Nuclear Information System (INIS)

    Heidbrink, W W; Fredrickson, E; Gorelenkov, N N; Hyatt, A W; Kramer, G; Luo, Y

    2003-01-01

    The major radius dependence of Alfven mode stability is studied by creating plasmas with similar minor radius, shape, magnetic field (0.5 T), density (n e ≅3x10 19 m -3 ), electron temperature (1.0 keV) and beam ion population (near-tangential 80 keV deuterium injection) on both NSTX and DIII-D. The major radius of NSTX is half the major radius of DIII-D. The super-Alfvenic beam ions that drive the modes have overlapping values of v f /v A in the two devices. Observed beam-driven instabilities include toroidicity-induced Alfven eigenmodes (TAE). The stability threshold for the TAE is similar in the two devices. As expected theoretically, the most unstable toroidal mode number n is larger in DIII-D

  1. Lack of negative charge in the E46Q mutant of photoactive yellow protein prevents partial unfolding of the blue shifted intermediate

    NARCIS (Netherlands)

    Derix, N.M.; Wechselberger, R.W.|info:eu-repo/dai/nl/304829005; van der Horst, M.A.; Hellingwerf, K.J.; Boelens, R.|info:eu-repo/dai/nl/070151407; Kaptein, R.|info:eu-repo/dai/nl/074334603; van Nuland, N.A.J.

    2003-01-01

    The long-lived light-induced intermediate (pB) of the E46Q mutant (glutamic acid is replaced by glutamine at position 46) of photoactive yellow protein (PYP) has been investigated by NMR spectroscopy. The ground state of this mutant is very similar to that of wild-type PYP (WT), whereas the pB

  2. Compressional Alfven Eigenmode Similarity Study

    Science.gov (United States)

    Heidbrink, W. W.; Fredrickson, E. D.; Gorelenkov, N. N.; Rhodes, T. L.

    2004-11-01

    NSTX and DIII-D are nearly ideal for Alfven eigenmode (AE) similarity experiments, having similar neutral beams, fast-ion to Alfven speed v_f/v_A, fast-ion pressure, and shape of the plasma, but with a factor of 2 difference in the major radius. Toroidicity-induced AE with ˜100 kHz frequencies were compared in an earlier study [1]; this paper focuses on higher frequency AE with f ˜ 1 MHz. Compressional AE (CAE) on NSTX have a polarization, dependence on the fast-ion distribution function, frequency scaling, and low-frequency limit that are qualitatively consistent with CAE theory [2]. Global AE (GAE) are also observed. On DIII-D, coherent modes in this frequency range are observed during low-field (0.6 T) similarity experiments. Experiments will compare the CAE stability limits on DIII-D with the NSTX stability limits, with the aim of determining if CAE will be excited by alphas in a reactor. Predicted differences in the frequency splitting Δ f between excited modes will also be used. \\vspace0.25em [1] W.W. Heidbrink, et al., Plasmas Phys. Control. Fusion 45, 983 (2003). [2] E.D. Fredrickson, et al., Princeton Plasma Physics Laboratory Report PPPL-3955 (2004).

  3. Flavonoid accumulation patterns of transparent testa mutants of arabidopsis

    Science.gov (United States)

    Peer, W. A.; Brown, D. E.; Tague, B. W.; Muday, G. K.; Taiz, L.; Murphy, A. S.

    2001-01-01

    Flavonoids have been implicated in the regulation of auxin movements in Arabidopsis. To understand when and where flavonoids may be acting to control auxin movement, the flavonoid accumulation pattern was examined in young seedlings and mature tissues of wild-type Arabidopsis. Using a variety of biochemical and visualization techniques, flavonoid accumulation in mature plants was localized in cauline leaves, pollen, stigmata, and floral primordia, and in the stems of young, actively growing inflorescences. In young Landsberg erecta seedlings, aglycone flavonols accumulated developmentally in three regions, the cotyledonary node, the hypocotyl-root transition zone, and the root tip. Aglycone flavonols accumulated at the hypocotyl-root transition zone in a developmental and tissue-specific manner with kaempferol in the epidermis and quercetin in the cortex. Quercetin localized subcellularly in the nuclear region, plasma membrane, and endomembrane system, whereas kaempferol localized in the nuclear region and plasma membrane. The flavonoid accumulation pattern was also examined in transparent testa mutants blocked at different steps in the flavonoid biosynthesis pathway. The transparent testa mutants were shown to have precursor accumulation patterns similar to those of end product flavonoids in wild-type Landsberg erecta, suggesting that synthesis and end product accumulation occur in the same cells.

  4. Normal and mutant HTT interact to affect clinical severity and progression in Huntington disease

    DEFF Research Database (Denmark)

    Aziz, N A; Jurgens, C K; Landwehrmeyer, G B

    2009-01-01

    OBJECTIVE: Huntington disease (HD) is an autosomal dominant neurodegenerative disorder caused by a CAG repeat expansion in the HD gene (HTT). We aimed to assess whether interaction between CAG repeat sizes in the mutant and normal allele could affect disease severity and progression. METHODS: Using...... with less severe symptoms and pathology. CONCLUSIONS: Increasing CAG repeat size in normal HTT diminishes the association between mutant CAG repeat size and disease severity and progression in Huntington disease. The underlying mechanism may involve interaction of the polyglutamine domains of normal...

  5. Overexpression of SOS genes in ciprofloxacin resistant Escherichia coli mutants.

    Science.gov (United States)

    Pourahmad Jaktaji, Razieh; Pasand, Shirin

    2016-01-15

    Fluoroquinolones are important antibiotics for the treatment of urinary tract infections caused by Escherichia coli. Mutational studies have shown that ciprofloxacin, a member of fluoroquinolones induces SOS response and mutagenesis in pathogenic bacteria which in turn develop antibiotic resistance. However, inhibition of SOS response can increase recombination activity which in turn leads to genetic variation. The aim of this study was to measure 5 SOS genes expressions in nine E. coli mutants with different MICs for ciprofloxacin following exposure to ciprofloxacin. Gene expression was assessed by quantitative real time PCR. Gene alteration assessment was conducted by PCR amplification and DNA sequencing. Results showed that the expression of recA was increased in 5 mutants. This overexpression is not related to gene alteration, and enhances the expression of polB and umuCD genes encoding nonmutagenic and mutagenic polymerases, respectively. The direct relationship between the level of SOS expression and the level of resistance to ciprofloxacin was also indicated. It was concluded that novel therapeutic strategy that inhibits RecA activity would enhance the efficiency of common antibiotics against pathogenic bacteria. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Identification and Characterization of Spontaneous Auxotrophic Mutants in Fusarium langsethiae

    Directory of Open Access Journals (Sweden)

    Olga Gavrilova

    2017-03-01

    Full Text Available Analysis of 49 strains of Fusarium langsethiae originating from northern Europe (Russia, Finland, Sweden, UK, Norway, and Latvia revealed the presence of spontaneous auxotrophic mutants that reflect natural intraspecific diversity. Our investigations detected that 49.0% of F. langsethiae strains were auxotrophic mutants for biotin, and 8.2% of the strains required thiamine as a growth factor. They failed to grow on vitamin-free media. For both prototrophic and auxotrophic strains, no growth defect was observed in rich organic media. Without essential vitamins, a significant reduction in the growth of the auxotrophic strains results in a decrease of the formation of T-2 toxin and diacetoxyscirpenol. In addition, all analysed F. langsethiae strains were distinguished into two subgroups based on PCR product sizes. According to our results, 26 and 23 strains of F. langsethiae belong to subgroups I and II respectively. We determined that the deletion in the intergenic spacer (IGS region of the rDNA of F. langsethiae belonging to subgroup II is linked with temperature sensitivity and causes a decrease in strain growth at 30 °C. Four thiamine auxotrophic strains were found in subgroup I, while 21 biotin auxotrophic strains were detected in subgroups II. To the best of our knowledge, the spontaneous mutations in F. langsethiae observed in the present work have not been previously reported.

  7. Structural dataset for the PPARγ V290M mutant

    Directory of Open Access Journals (Sweden)

    Ana C. Puhl

    2016-06-01

    Full Text Available Loss-of-function mutation V290M in the ligand-binding domain of the peroxisome proliferator activated receptor γ (PPARγ is associated with a ligand resistance syndrome (PLRS, characterized by partial lipodystrophy and severe insulin resistance. In this data article we discuss an X-ray diffraction dataset that yielded the structure of PPARγ LBD V290M mutant refined at 2.3 Å resolution, that allowed building of 3D model of the receptor mutant with high confidence and revealed continuous well-defined electron density for the partial agonist diclofenac bound to hydrophobic pocket of the PPARγ. These structural data provide significant insights into molecular basis of PLRS caused by V290M mutation and are correlated with the receptor disability of rosiglitazone binding and increased affinity for corepressors. Furthermore, our structural evidence helps to explain clinical observations which point out to a failure to restore receptor function by the treatment with a full agonist of PPARγ, rosiglitazone.

  8. Similarity analysis between quantum images

    Science.gov (United States)

    Zhou, Ri-Gui; Liu, XingAo; Zhu, Changming; Wei, Lai; Zhang, Xiafen; Ian, Hou

    2018-06-01

    Similarity analyses between quantum images are so essential in quantum image processing that it provides fundamental research for the other fields, such as quantum image matching, quantum pattern recognition. In this paper, a quantum scheme based on a novel quantum image representation and quantum amplitude amplification algorithm is proposed. At the end of the paper, three examples and simulation experiments show that the measurement result must be 0 when two images are same, and the measurement result has high probability of being 1 when two images are different.

  9. Similarity flows in relativistic hydrodynamics

    International Nuclear Information System (INIS)

    Blaizot, J.P.; Ollitrault, J.Y.

    1986-01-01

    In ultra-relativistic heavy ion collisions, one expects in particular to observe a deconfinement transition leading to a formation of quark gluon plasma. In the framework of the hydrodynamic model, experimental signatures of such a plasma may be looked for as observable consequences of a first order transition on the evolution of the system. In most of the possible scenario, the phase transition is accompanied with discontinuities in the hydrodynamic flow, such as shock waves. The method presented in this paper has been developed to treat without too much numerical effort such discontinuous flow. It relies heavily on the use of similarity solutions of the hydrodynamic equations

  10. PNRI mutant variety: sansevieria 'Sword of Ibe'

    International Nuclear Information System (INIS)

    Aurigue, Fernando B.

    2011-01-01

    Sansevieria 'Sword of Ibe,' registered by the Philippine Nuclear Research Institute as NSIC 2008 Or-66, is a chlorophyll mutant of Sansevieria trifasciata 'Moonshine' developed by treating its suckers or shoots arising from a rhizome with acute gamma radiation from a Cobalt-60 source. The new mutant is identical in growth habit and vigor to Sansevieria 'Moonshine,' also known as Moonglow. Results of this mutation breeding experiment showed that leaf color and flowering were altered by gamma irradiation without changing the other characteristics of the plant. Propagation is true-to-type by separation of sucker and top cutting. The plant is recommended for use as landscaping material and as pot plant for indoor and outdoor use. The leaves may be harvested as cut foliage for Japanese flower arrangements. (author)

  11. Serine:glyoxylate aminotransferase mutant of barley

    International Nuclear Information System (INIS)

    Blackwell, R.; Murray, A.; Joy, K.; Lea, P.

    1987-01-01

    A photorespiratory mutant of barley (LaPr 85/84), deficient in both of the major peaks of serine:glyoxylate aminotransferase activity detected in the wild type, also lacks serine:pyruvate and asparagine:glyoxylate aminotransferase activities. Genetic analysis of the mutation demonstrated that these three activities are all carried on the same enzyme. The mutant, when placed in air, accumulated a large pool of serine, showed the expected rate (50%) of ammonia release during photorespiration but produced CO 2 at twice the wild type rate when it was fed [ 14 C] glyoxylate. Compared with the wild type, LaPr 85/84 exhibited abnormal transient changes in chlorophyll a fluorescence when the CO 2 concentration of the air was altered, indicating that the rates of the fluorescence quenching mechanisms were affected in vivo by the lack of this enzyme

  12. Intact interval timing in circadian CLOCK mutants.

    Science.gov (United States)

    Cordes, Sara; Gallistel, C R

    2008-08-28

    While progress has been made in determining the molecular basis for the circadian clock, the mechanism by which mammalian brains time intervals measured in seconds to minutes remains a mystery. An obvious question is whether the interval-timing mechanism shares molecular machinery with the circadian timing mechanism. In the current study, we trained circadian CLOCK +/- and -/- mutant male mice in a peak-interval procedure with 10 and 20-s criteria. The mutant mice were more active than their wild-type littermates, but there were no reliable deficits in the accuracy or precision of their timing as compared with wild-type littermates. This suggests that expression of the CLOCK protein is not necessary for normal interval timing.

  13. The application of shortened upper leaf mutant in barley breeding

    International Nuclear Information System (INIS)

    Jin Hua

    2004-01-01

    The shortened upper leaf mutant was induced from Fuji Nigo by γ-ray irradiation. Fuji Nigo, the mutant, cross-cut F 1 , F 2 and back-cross F 1 , F 2 were used to analyze mutant heredity by comparative study. The yield, chlorophyll content, light intensity, dry matter of mutant were investigated. The results showed that (1) the mutant character was controlled by a couple of nuclear genes which were partial dominance; (2) the transmittance of the mutant colony was better than that of Fuji Nigo and bottom dry matter was much more than that of Fuji Nigo; (3) under the condition of high fertilizer and high plant population , the yield of mutant was higher than that of Fuji Nigo; (4) the content of chlorophyll a in the mutant was higher than that in Fuji Nigo

  14. Selection and genetic relationship of salt tolerant rice mutants by in vitro mutagenesis

    Energy Technology Data Exchange (ETDEWEB)

    Song, Jae Young; Kim, Dong Sub; Lee, Kyung Jun; Kim, Jin Baek; Kim, Sang Hoon; Kang, Si Yong [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Lee, Myung Chul [National Academy of Agriculture and Science, Suwon (Korea, Republic of); Yun, Song Joong [Chonbuk National University, Jeonju (Korea, Republic of)

    2010-12-15

    Plants have evolved physiological, biochemical and metabolic mechanisms to increase their survival under the adverse conditions. This present study has been performed to select salt tolerant rice mutant lines through in vivo and in vitro mutagenesis with gamma-rays. For the selection of the salt-tolerant rice mutants, we conducted three times of selection procedure using 1,500 gamma ray mutant lines resulted from an embryo culture of the original rice cv. Dongan (wild-type, WT): first, selection in the a nutrient solution with 171 mM NaCI: second, selection under in vitro condition with 171 mM NaCI: and third, selection in a reclaimed saline land. Based on a growth comparison of the entries, out of the mutant lines, two putative 2 salt tolerant (ST) rice mutant lines, ST-87 and ST-301, were finally selected. The survival rate of the WT, ST-87 and ST-301 were 36.6%, 60% and 66.3% after 7 days in 171 mM NaCI treatment, respectively. The WT and two salt tolerant mutant lines were used to analyze their genetic variations. A total of 21 EcoRI and Msel primer combinations were used to analyze the genetic relationship of among the two salt tolerant lines and the WT using the ABI3130 capillary electrophoresis system. In the AFLP analysis, a total of 1469 bands were produced by the 21 primer combinations, and 700 (47.6%) of them were identified as having polymorphism. The genetic similarity coefficients were ranged from 0.52 between the ST-87 and WT to 0.24 between the ST-301 and the WT. These rice mutant lines will be used as a control plot for physiological analysis and genetic research on salt tolerance.

  15. Characterization and fine mapping of a light-dependent leaf lesion mimic mutant 1 in rice.

    Science.gov (United States)

    Wang, Jing; Ye, Bangquan; Yin, Junjie; Yuan, Can; Zhou, Xiaogang; Li, Weitao; He, Min; Wang, Jichun; Chen, Weilan; Qin, Peng; Ma, Bintian; Wang, Yuping; Li, Shigui; Chen, Xuewei

    2015-12-01

    Plants that spontaneously produce lesion mimics or spots, without any signs of obvious adversity, such as pesticide and mechanical damage, or pathogen infection, are so-called lesion mimic mutants (lmms). In rice, many lmms exhibit enhanced resistance to pathogens, which provides a unique opportunity to uncover the molecular mechanism underlying lmms. We isolated a rice light-dependent leaf lesion mimic mutant 1 (llm1). Lesion spots appeared in the leaves of the llm1 mutant at the tillering stage. Furthermore, the mutant llm1 had similar agronomic traits to wild type rice. Trypan blue and diamiobenzidine staining analyses revealed that the lesion spot formation on the llm1 mutant was due to programmed cell death and reactive oxygen species. The chloroplasts were severely damaged in the llm1 mutant, suggesting that chloroplast damage was associated with the formation of lesion spots in llm1. More importantly, llm1 exhibited enhanced resistance to bacterial blight pathogens within increased expression of pathogenesis related genes (PRs). Using a map-based cloning approach, we delimited the LLM1 locus to a 121-kb interval between two simple sequence repeat markers, RM17470 and RM17473, on chromosome 4. We sequenced the candidate genes on the interval and found that a base mutation had substituted adenine phosphate for thymine in the last exon of LOC_Os04g52130, which led to an amino acid change (Asp(388) to Val) in the llm1 mutant. Our investigation showed that the putative coproporphyrinogen III oxidase (CPOX) encoded by LOC_Os04g52130 was produced by LLM1 and that amino acid Asp(388) was essential for CPOX function. Our study provides the basis for further investigations into the mechanism underlying lesion mimic initiation associated with LLM1. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  16. ''Fushi'' - excellent mutant germplasm for peanut improvement

    International Nuclear Information System (INIS)

    Jiang, X.; Zhou, Y.

    1989-01-01

    Full text: The mutant line ''Fushi'' was selected following seed treatment of the variety ''Shi Xuan 64'' in 1960 with 32 P. Many good peanut varieties were developed using ''Fushi'' in cross-breeding (ref. Mutation Breeding Newsletter No. 30 (July 1987) p. 2-3). In the past 10 years, planting areas of these varieties added up to 3,3 million ha in South China, peanut production was increased by more than 500 000 t valued 500 million Yuan. (author)

  17. Radiation induced early maturing mutants in barley

    International Nuclear Information System (INIS)

    Kumar, R.; Chauhan, S.V.S.; Sharma, R.P.

    1978-01-01

    In M 2 generation, two early maturing plants were screened from a single spike progeny of a plant obtained from 20 kR of gamma-ray irradiation of a six-rowed barley (Hordeum vulgare L. var. Jyoti). Their true breeding nature was confirmed in M 3 generation. These mutants flower and mature 38 and 22 days earlier than those of control. (auth.)

  18. Self-similar gravitational clustering

    International Nuclear Information System (INIS)

    Efstathiou, G.; Fall, S.M.; Hogan, C.

    1979-01-01

    The evolution of gravitational clustering is considered and several new scaling relations are derived for the multiplicity function. These include generalizations of the Press-Schechter theory to different densities and cosmological parameters. The theory is then tested against multiplicity function and correlation function estimates for a series of 1000-body experiments. The results are consistent with the theory and show some dependence on initial conditions and cosmological density parameter. The statistical significance of the results, however, is fairly low because of several small number effects in the experiments. There is no evidence for a non-linear bootstrap effect or a dependence of the multiplicity function on the internal dynamics of condensed groups. Empirical estimates of the multiplicity function by Gott and Turner have a feature near the characteristic luminosity predicted by the theory. The scaling relations allow the inference from estimates of the galaxy luminosity function that galaxies must have suffered considerable dissipation if they originally formed from a self-similar hierarchy. A method is also developed for relating the multiplicity function to similar measures of clustering, such as those of Bhavsar, for the distribution of galaxies on the sky. These are shown to depend on the luminosity function in a complicated way. (author)

  19. Adhesion defective BHK cell mutant has cell surface heparan sulfate proteoglycan of altered properties

    DEFF Research Database (Denmark)

    Couchman, J R; Austria, R; Woods, A

    1988-01-01

    In the light of accumulating data that implicate cell surface heparan sulfate proteoglycans (HSPGs) with a role in cell interactions with extracellular matrix molecules such as fibronectin, we have compared the properties of these molecules in wild-type BHK cells and an adhesion-defective ricin......-resistant mutant (RicR14). Our results showed that the mutant, unlike BHK cells, cannot form focal adhesions when adherent to planar substrates in the presence of serum. Furthermore, while both cell lines possess similar amounts of cell surface HSPG with hydrophobic properties, that of RicR14 cells had decreased...... sulfation, reduced affinity for fibronectin and decreased half-life on the cell surface when compared to the normal counterpart. Our conclusions based on this data are that these altered properties may, in part, account for the adhesion defect in the ricin-resistant mutant. Whether this results from...

  20. Grain product of 34 soya mutant lines

    International Nuclear Information System (INIS)

    Salmeron E, J.; Mastache L, A. A.; Valencia E, F.; Diaz V, G. E.; Cervantes S, T.; De la Cruz T, E.; Garcia A, J. M.; Falcon B, T.; Gatica T, M. A.

    2009-01-01

    This work was development with the objective of obtaining information of the agronomic behavior of 34 soya mutant lines (R 4 M 18 ) for human consumption and this way to select the 2 better lines. The genetic materials were obtained starting from the variety ISAAEG-B M2 by means of the application of recurrent radiation with Co 60 gammas, to a dose of 350 Gray for the first two generations and both later to 200 Gray and selection during 17 cycles, being obtained the 34 better lines mutants with agronomic characteristic wanted and good flavor. The obtained results were that the mutant lines L 25 and L 32 produced the major quantity in branches/plant number with 7.5 and 7.25, pods/plant number with 171.25 and 167, grains/plant number with 350.89 and 333.07 and grain product (ton/ha) to 15% of humidity 5.15 and 4.68 ton/ha, respectively. (Author)

  1. Multivariate analysis for selecting apple mutants

    International Nuclear Information System (INIS)

    Faedi, W.; Bagnara, G.L.; Rosati, P.; Cecchini, M.

    1992-01-01

    The mutlivariate analysis of four year records on several vegetative and productive traits of twenty-one apple mutants (3 of 'Jonathan', 3 of 'Ozark Gold', 14 of 'Mollie's Delicious', 1 of 'Neipling's Early Stayman)' induced by gamma radiations showed that observation of some traits of one-year-old shoots is the most efficient way to reveal compact growing apple mutants. In particular, basal cross-section area, total length and leaf area resulted the most appropriate parameters, while internode length together with conopy height and width are less appropriate. The most interesting mutants we found are: one of 'Mollie's Delicious for the best balance among tree and fruit traits and for high skin color; one of 'Neipling's Early Stayman' with an earlier and more extensively red colored apple than the original clone. (author)

  2. Probiotic features of Lactobacillus plantarum mutant strains.

    Science.gov (United States)

    Bove, Pasquale; Gallone, Anna; Russo, Pasquale; Capozzi, Vittorio; Albenzio, Marzia; Spano, Giuseppe; Fiocco, Daniela

    2012-10-01

    In this study, the probiotic potential of Lactobacillus plantarum wild-type and derivative mutant strains was investigated. Bacterial survival was evaluated in an in vitro system, simulating the transit along the human oro-gastro-intestinal tract. Interaction with human gut epithelial cells was studied by assessing bacterial adhesive ability to Caco-2 cells and induction of genes involved in innate immunity. L. plantarum strains were resistant to the combined stress at the various steps of the simulated gastrointestinal tract. Major decreases in the viability of L. plantarum cells were observed mainly under drastic acidic conditions (pH ≤ 2.0) of the gastric compartment. Abiotic stresses associated to small intestine poorly affected bacterial viability. All the bacterial strains significantly adhered to Caco-2 cells, with the ΔctsR mutant strain exhibiting the highest adhesion. Induction of immune-related genes resulted higher upon incubation with heat-inactivated bacteria rather than with live ones. For specific genes, a differential transcriptional pattern was observed upon stimulation with different L. plantarum strains, evidencing a possible role of the knocked out bacterial genes in the modulation of host cell response. In particular, cells from Δhsp18.55 and ΔftsH mutants strongly triggered immune defence genes. Our study highlights the relevance of microbial genetic background in host-probiotic interaction and might contribute to identify candidate bacterial genes and molecules involved in probiosis.

  3. Isolation and characterisation of a dwarf rice mutant exhibiting defective gibberellins biosynthesis.

    Science.gov (United States)

    Ji, S H; Gururani, M A; Lee, J W; Ahn, B-O; Chun, S-C

    2014-03-01

    We have isolated a severe dwarf mutant derived from a Ds (Dissociation) insertion mutant rice (Oryza sativa var. japonica c.v. Dongjin). This severe dwarf phenotype, has short and dark green leaves, reduced shoot growth early in the seedling stage, and later severe dwarfism with failure to initiate flowering. When treated with bioactive GA3 , mutants are restored to the normal wild-type phenotype. Reverse transcription PCR analyses of 22 candidate genes related to the gibberellin (GA) biosynthesis pathway revealed that among 22 candidate genes tested, a dwarf mutant transcript was not expressed only in one OsKS2 gene. Genetic analysis revealed that the severe dwarf phenotype was controlled by recessive mutation of a single nuclear gene. The putative OsKS2 gene was a chromosome 4-located ent-kaurene synthase (KS), encoding the enzyme that catalyses an early step of the GA biosynthesis pathway. Sequence analysis revealed that osks2 carried a 1-bp deletion in the ORF region of OsKS2, which led to a loss-of-function mutation. The expression pattern of OsKS2 in wild-type cv Dongjin, showed that it is expressed in all organs, most prominently in the stem and floral organs. Morphological characteristics of the dwarf mutant showed dramatic modifications in internal structure and external morphology. We propose that dwarfism in this mutant is caused by a point mutation in OsKS2, which plays a significant role in growth and development of higher plants. Further investigation on OsKS2 and other OsKS-like proteins is underway and may yield better understanding of the putative role of OsKS in severe dwarf mutants. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

  4. Evaluation of Some Chemical Characteristics of barley Mutants induced by Gamma Irradiation

    International Nuclear Information System (INIS)

    Abdeldaiem, M.H.; Ali, H.G.M.

    2011-01-01

    This study aims to evaluate the antioxidant activity of acetonic extract from some barley mutations (P1, P2 and P3 varieties) induced by gamma irradiation as compared with local barley variety (Hordeum vulgare L.) as control. Barley samples were obtained from Plant Breeding Unit, Plant Research Department, Nuclear Research Centre, Atomic Energy Authority, Egypt. The measurements of the antioxidant activity using a radical scavenging capacity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ?-carotene bleaching assay were assessed in the barley acetonic extract. Furthermore, amino acids composition of barley mutant samples was determined. The results indicated that the acetonic extract of barley varieties under investigation possess marked antioxidant and anti radical capacities. The data showed that the acetonic extract of barley mutant P1 possessed the higher antioxidant activity as compared with the antioxidant activities of acetonic extract from control and other barley mutant samples. Meanwhile, the flour of barley mutations under investigation contained trace elements of iron, copper and manganese. GC and mass analyses were used to identify the active compound of extract of control and mutant barley samples. The results illustrated that the main components of the control sample of barely extract was pentane, 3 methyl (47.73%) while gamma irradiation caused noticeable change in the relative percentage of some components of acetonic extract from barley mutant samples. Moreover, the results presented that changes were disappeared, and some compounds of the acetonic extract from mutant barley samples were appeared. Furthermore, the results exhibited that barley flour supplemented with wheat flour at 30% level produced acceptable cookies. Accordingly, the phenolic constituents of barley acetonic extract induced by gamma irradiation, especially samples of P1 mutant, may have a future role as ingredients in the development of functional foods.

  5. Complete sterility studies in three mutants of cowpea (Vigna Unguiculata (L.) walp

    International Nuclear Information System (INIS)

    Adu-Dapaah, H. K.; Singh, B. B.; Fatokun, C. A.

    1999-01-01

    Three completely-sterile cowpea mutants IT85D-3625, IT85D-3628, IT85D-3641 obtained from spontaneous mutation and gamma irradiation were-characterized. Reciprocal crosses between them and fertile plants failed to set pods. These lines showed significant differences with respect to various traits such as number of pollen grain per anther, anther length and width, plant height, anther indehiscence,unopened flower buds, and premature abortion of pods and seeds. The major cause of sterility was chromosome aberrations. Complete sterility in each of the three lines was conditioned by a simple recessive gene pair. Sterility in each of the three mutants was associated with floral aberrations. The symbols cs 1 , cs 2 and cs 3 are being assigned to IT85D-3625, IT85D-2628 and IT85D-3641 respectively. The three mutants were homogeneous with reference to sterility inheritance. (au)

  6. The use of RAPD fingerprinting to detect genetic variation of a selected signal grass mutant

    International Nuclear Information System (INIS)

    Affrida Abu Hassan; Ghazali HAzhar Mohamad; Abdul Rahim Harun

    2002-01-01

    Signal grass (Brachiaria decumbens) has been used for many years as grazing pasture for ruminants but it may know to be toxic to small ruminants. Mutagenesis provides an alternative approach to create phenotypic variability in the grass that might be free from toxicity and allow greater selection potential for desired characteristics. The mutant of Brachiara decumbens, which was obtained through induced mutation by gamma irradiation at dose 900 Gh showed phenotypic changes in term of tiller number, leaf to stem ratio and internode length. The variations caused by irradiation were detected by Random Amplified Polymorphic DNA (RAPD) analysis. Decamer oligonucleotide primers were used to generate DNA profiles. 575 bp polymorphic DNA band was observed between control and the mutant. RAPD has been proven to be useful to detect polymorphism between mutants and the control. (Author)

  7. Traits and meiosis in mutant of impatiens balsamina induced by space treatment

    International Nuclear Information System (INIS)

    Tang Zesheng; Yang Jun; Zhao Yan; Yuan Haiyun

    2004-01-01

    A mutant of Impatiens balsamina was obtained after space induction, and its traits and meiosis were investigated. Characters such as color and form of the mutant expressed great variation. Observation of meiosis showed that most of pollen mother cells were normal in meiosis phase I, except the disproportion of chromosomal segregation, lagging chromosome and dispersal chromosome in anaphase I. Most pollen mother cells developed into microspores tetrad after meiosis, but paraspores also appeared. The number of chromosome in microspore varied from 1 to 21, even more than 30. The shape and size of the microspores fluctuated apparently, and the size of the microspores was in positive correlation to chromosome number. When staining with iodic solution, most of the pollens showed sterility, which was in consistence with the low setting percentage of the mutant plant. It was thought that space induction caused the variation of size, fertility and the abnormal meiosis

  8. Analysis on expression of gene for flower shape in Dendrobium sonia mutants using differential display technique

    International Nuclear Information System (INIS)

    Affrida Abu Hassan; Ahmad Syazni Kamarudin; Nurul Nadia Aminuddin; Mohd Nazir Basiran

    2004-01-01

    In vitro mutagenesis on Dendrobium Sonia in MINT has produced mutants with wide range of flower form and colour variations. Among the mutants are plants with different flower size and shape. These changes could be caused by alterations to the expression level of the genes responsible for the characteristics. In this studies, Differential Display technique was used to identify and analyse altered gene expression at the mRNA level. Total RNA of the control and mutants were reversed transcribed using three anchored oligo-d T primers. Subsequently, these cDNAs were Pcr amplified in combination with 16 arbitrary primers. The amplified products were electrophoresed side by side on agarose gel. Differentially expressed bands are isolated for further analysis. (Author)

  9. Radiation studies in Cajanus cajan: meiotic behaviour in some M/sub 2/ mutants

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, S.S.N.; Akhaury, S.B. (Ranchi Univ. (India). Dept. of Botany)

    1982-01-01

    A qualitative study of the mutants produced in M/sub 2/ generation has been made. The mutants were classified as: (1) chlorophyll mutant, (2) morphological mutant, (3) pollen mutant, (4) semi-sterile and (5) sterile mutant. Cytological investigations of pollen mutants, sterile and semi-sterile mutants have revealed that these mutants generally arise at higher dose levels (20 Kr and 25 Kr).

  10. Neurobehavioral performances and brain regional metabolism in Dab1(scm) (scrambler) mutant mice.

    Science.gov (United States)

    Jacquelin, C; Lalonde, R; Jantzen-Ossola, C; Strazielle, C

    2013-09-01

    As disabled-1 (DAB1) protein acts downstream in the reelin signaling pathway modulating neuronal migration, glutamate neurotransmission, and cytoskeletal function, the disabled-1 gene mutation (scrambler or Dab1(scm) mutation) results in ataxic mice displaying dramatic neuroanatomical defects similar to those observed in the reeler gene (Reln) mutation. By comparison to non-ataxic controls, Dab1(scm) mutants showed severe motor coordination impairments on stationary beam, coat-hanger, and rotorod tests but were more active in the open-field. Dab1(scm) mutants were also less anxious in the elevated plus-maze but with higher latencies in the emergence test. In mutants versus controls, changes in regional brain metabolism as measured by cytochrome oxidase (COX) activity occurred mainly in structures intimately connected with the cerebellum, in basal ganglia, in limbic regions, particularly hippocampus, as well as in visual and parietal sensory cortices. Although behavioral results characterized a major cerebellar disorder in the Dab1(scm) mutants, motor activity impairments in the open-field were associated with COX activity changes in efferent basal ganglia structures such as the substantia nigra, pars reticulata. Metabolic changes in this structure were also associated with the anxiety changes observed in the elevated plus-maze and emergence test. These results indicate a crucial participation of the basal ganglia in the functional phenotype of ataxic Dab1(scm) mutants. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Identification of Mutant Genes and Introgressed Tiger Salamander DNA in the Laboratory Axolotl, Ambystoma mexicanum.

    Science.gov (United States)

    Woodcock, M Ryan; Vaughn-Wolfe, Jennifer; Elias, Alexandra; Kump, D Kevin; Kendall, Katharina Denise; Timoshevskaya, Nataliya; Timoshevskiy, Vladimir; Perry, Dustin W; Smith, Jeramiah J; Spiewak, Jessica E; Parichy, David M; Voss, S Randal

    2017-01-31

    The molecular genetic toolkit of the Mexican axolotl, a classic model organism, has matured to the point where it is now possible to identify genes for mutant phenotypes. We used a positional cloning-candidate gene approach to identify molecular bases for two historic axolotl pigment phenotypes: white and albino. White (d/d) mutants have defects in pigment cell morphogenesis and differentiation, whereas albino (a/a) mutants lack melanin. We identified in white mutants a transcriptional defect in endothelin 3 (edn3), encoding a peptide factor that promotes pigment cell migration and differentiation in other vertebrates. Transgenic restoration of Edn3 expression rescued the homozygous white mutant phenotype. We mapped the albino locus to tyrosinase (tyr) and identified polymorphisms shared between the albino allele (tyr a ) and tyr alleles in a Minnesota population of tiger salamanders from which the albino trait was introgressed. tyr a has a 142 bp deletion and similar engineered alleles recapitulated the albino phenotype. Finally, we show that historical introgression of tyr a significantly altered genomic composition of the laboratory axolotl, yielding a distinct, hybrid strain of ambystomatid salamander. Our results demonstrate the feasibility of identifying genes for traits in the laboratory Mexican axolotl.

  12. Hypermutability of a UV-sensitive aphidicolin-resistant mutant of Chinese hamster fibroblasts

    International Nuclear Information System (INIS)

    Liu, P.K.; Chang, C.; Trosko, J.E.

    1982-01-01

    An ultraviolet light (UV)-sensitive thymidine auxotroph of Chinese hamster V79 cells that exhibits pleiotropic effects such as a high level of deoxycytidine triphosphate, slow growth, sensitivity to cytidine, and high frequencies of site-specific bromodeoxyuridine-dependent chromosomal aberrations was selected by its resistance to aphidicolin. The UV-induced mutability of this mutant and one of its revertants, which retains some of the phenotypes listed above, was studied in 3 mutation assay systems. The results showed that the mutant was hypermutable for ouabain and diphtheria-toxin-resistant mutations compared to wild-type V79 cells at the same UV dose or the same survival level. The mutant exhibits a delayed expression of maximal frequency of induced 6-thioguanine-resistant mutants. When maximal frequencies are compared at the same UV dose, the mutant also has higher mutation frequencies at the hypoxanthine-guanine phosphoribosyl transferase locus. The revertant was similar to the wild-type in UV sensitivity and mutability. (orig./AJ)

  13. An apoptotic cell cycle mutant in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Villadsen, Ingrid

    1996-01-01

    The simple eukaryote Saccharomyces cerevisiae has proved to be a useful organism for elucidating the mechanisms that govern cell cycle progression in eukaryotic cells. The excellent in vivo system permits a cell cycle study using temperature sensitive mutants. In addition, it is possible to study...... many genes and gene products from higher eukaryotes in Saccharomyces cerevisiae because many genes and biological processes are homologous or similar in lower and in higher eukaryotes. The highly developed methods of genetics and molecular biology greatly facilitates studies of higher eukaryotic...... processes.Programmmed cell death with apoptosis plays a major role in development and homeostatis in most, if not all, animal cells. Apoptosis is a morphologically distinct form of death, that requires the activation of a highly regulated suicide program. Saccharomyces cerevisiae provides a new system...

  14. Molecular analysis of mutants of the Neurospora adenylosuccinate ...

    Indian Academy of Sciences (India)

    2012-08-07

    Aug 7, 2012 ... and mutants induced with X-ray, UV or chemical mutagens. ... We have sequenced the ad-8 locus from 13 of these mutants and identified the molecular nature ..... mutants in yeast by selection for constitutive behavior in pig-.

  15. Biological changes in Barley mutants resistant to powdery mildew disease

    International Nuclear Information System (INIS)

    Amer, I. M.; Fahim, M. M.; Moustafa, N. A.

    2012-12-01

    physiological studies showed that all kinds of chlorophyll (a), (b) and (a + b) content in infected plant were decreased while, the carotenes pigment were increased. Infection generally reduced total sugars content of all resistant mutants. Infected resistant mutant showed more phenols content and peroxidase, polyphenoloxidase activities than healthy ones of the mutants. (Author)

  16. Seniority bosons from similarity transformations

    International Nuclear Information System (INIS)

    Geyer, H.B.

    1986-01-01

    The requirement of associating in the boson space seniority with twice the number of non-s bosons defines a similarity transformation which re-expresses the Dyson pair boson images in terms of seniority bosons. In particular the fermion S-pair creation operator is mapped onto an operator which, unlike the pair boson image, does not change the number of non-s bosons. The original results of Otsuka, Arima and Iachello are recovered by this procedure while at the same time they are generalized to include g-bosons or even bosons with J>4 as well as any higher order boson terms. Furthermore the seniority boson images are valid for an arbitrary number of d- or g-bosons - a result which is not readily obtainable within the framework of the usual Marumori- or OAI-method

  17. Symptomatic type 1 protein C deficiency caused by a de novo Ser270Leu mutation in the catalytic domain

    DEFF Research Database (Denmark)

    Lind, B; Koefoed, P; Thorsen, S

    2001-01-01

    the intracellular content of mutant and wild-type protein was similar. Northern blot analysis of total mRNA from transfected cells showed no reduction of the mutant protein C mRNA compared with wild-type protein C mRNA. Collectively, these results indicate that the Ser270Leu mutation in the affected family caused......Heterozygosity for a C8524T transition in the protein C gene converting Ser270(TCG) to Leu(TTG) in the protease domain was identified in a family with venous thrombosis. The mutation was associated with parallel reduction in plasma levels of protein C anticoagulant activity and protein C antigen......, which is consistent with a type 1 deficiency. Transient expression of mutant protein C cDNA in human kidney 293 cells and analysis of protein C antigen in culture media and cell lysates showed that the secretion of mutant protein compared with wild-type protein was reduced by at least 97% while...

  18. Rapid identification of lettuce seed germination mutants by bulked segregant analysis and whole genome sequencing.

    Science.gov (United States)

    Huo, Heqiang; Henry, Isabelle M; Coppoolse, Eric R; Verhoef-Post, Miriam; Schut, Johan W; de Rooij, Han; Vogelaar, Aat; Joosen, Ronny V L; Woudenberg, Leo; Comai, Luca; Bradford, Kent J

    2016-11-01

    Lettuce (Lactuca sativa) seeds exhibit thermoinhibition, or failure to complete germination when imbibed at warm temperatures. Chemical mutagenesis was employed to develop lettuce lines that exhibit germination thermotolerance. Two independent thermotolerant lettuce seed mutant lines, TG01 and TG10, were generated through ethyl methanesulfonate mutagenesis. Genetic and physiological analyses indicated that these two mutations were allelic and recessive. To identify the causal gene(s), we applied bulked segregant analysis by whole genome sequencing. For each mutant, bulked DNA samples of segregating thermotolerant (mutant) seeds were sequenced and analyzed for homozygous single-nucleotide polymorphisms. Two independent candidate mutations were identified at different physical positions in the zeaxanthin epoxidase gene (ABSCISIC ACID DEFICIENT 1/ZEAXANTHIN EPOXIDASE, or ABA1/ZEP) in TG01 and TG10. The mutation in TG01 caused an amino acid replacement, whereas the mutation in TG10 resulted in alternative mRNA splicing. Endogenous abscisic acid contents were reduced in both mutants, and expression of the ABA1 gene from wild-type lettuce under its own promoter fully complemented the TG01 mutant. Conventional genetic mapping confirmed that the causal mutations were located near the ZEP/ABA1 gene, but the bulked segregant whole genome sequencing approach more efficiently identified the specific gene responsible for the phenotype. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  19. Plant cells without detectable plastids are generated in the crumpled leaf mutant of Arabidopsis thaliana.

    Science.gov (United States)

    Chen, Yuling; Asano, Tomoya; Fujiwara, Makoto T; Yoshida, Shigeo; Machida, Yasunori; Yoshioka, Yasushi

    2009-05-01

    Plastids are maintained in cells by proliferating prior to cell division and being partitioned to each daughter cell during cell division. It is unclear, however, whether cells without plastids are generated when plastid division is suppressed. The crumpled leaf (crl) mutant of Arabidopsis thaliana is a plastid division mutant that displays severe abnormalities in plastid division and plant development. We show that the crl mutant contains cells lacking detectable plastids; this situation probably results from an unequal partitioning of plastids to each daughter cell. Our results suggest that crl has a partial defect in plastid expansion, which is suggested to be important in the partitioning of plastids to daughter cells when plastid division is suppressed. The absence of cells without detectable plastids in the accumulation and replication of chloroplasts 6 (arc6) mutant, another plastid division mutant of A. thaliana having no significant defects in plant morphology, suggests that the generation of cells without detectable plastids is one of the causes of the developmental abnormalities seen in crl plants. We also demonstrate that plastids with trace or undetectable amounts of chlorophyll are generated from enlarged plastids by a non-binary fission mode of plastid replication in both crl and arc6.

  20. Biochemical characterization and cellular effects of CADASIL mutants of NOTCH3.

    Directory of Open Access Journals (Sweden)

    He Meng

    Full Text Available Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL is the best understood cause of dominantly inherited stroke and results from NOTCH3 mutations that lead to NOTCH3 protein accumulation and selective arterial smooth muscle degeneration. Previous studies show that NOTCH3 protein forms multimers. Here, we investigate protein interactions between NOTCH3 and other vascular Notch isoforms and characterize the effects of elevated NOTCH3 on smooth muscle gene regulation. We demonstrate that NOTCH3 forms heterodimers with NOTCH1, NOTCH3, and NOTCH4. R90C and C49Y mutant NOTCH3 form complexes which are more resistant to detergents than wild type NOTCH3 complexes. Using quantitative NOTCH3-luciferase clearance assays, we found significant inhibition of mutant NOTCH3 clearance. In coculture assays of NOTCH function, overexpressed wild type and mutant NOTCH3 significantly repressed NOTCH-regulated smooth muscle transcripts and potently impaired the activity of three independent smooth muscle promoters. Wildtype and R90C recombinant NOTCH3 proteins applied to cell cultures also blocked canonical Notch fuction. We conclude that CADASIL mutants of NOTCH3 complex with NOTCH1, 3, and 4, slow NOTCH3 clearance, and that overexpressed wild type and mutant NOTCH3 protein interfere with key NOTCH-mediated functions in smooth muscle cells.

  1. Induction of Male sterile mutants in vegetable crops

    Energy Technology Data Exchange (ETDEWEB)

    Nagata, Nobuhiko [Hokkaido National Agricultural Experiment Station, Sapporo (Japan)

    1982-03-01

    The cultivars of vegetable crops in Japan are almost all F/sub 1/ hybrid lines. These hybrid cultivars are superior in yield, quality and uniformity by heterosis, and play an important role in the protection of breeder's rights. Utilization of male sterile mutants has such advantages as the reduction of cost for F/sub 1/ production by saving labor, production of better seeds, that is, pollination without emasculation and avoidance of contamination caused by self pollination. Male sterility must be used for some species in which seed production is difficult because of tiny flowers and meager seed production by artificial crossing such as carrot and onion, and those in which pollination by bag or emasculation is expensive such as tomato, and sweet pepper. However, for vegetable crop breeeding, the induction and use of genetic male sterility are more difficult than for other crops, considering the economy and efficiency of research because the type of cultivars needed changes rapidly.

  2. NH exchange in point mutants of human ubiquitin.

    Science.gov (United States)

    Jahr, Nicole; Fiedler, Erik; Günther, Robert; Hofmann, Hans-Jörg; Berger, Stefan

    2011-08-01

    Several point mutants of human ubiquitin (Ub(T9V), Ub(F45W), Ub(F45G), and Ub(A46S)) were prepared by recombinant techniques. The NH exchange rate constants were measured by the NMR diffusion and the MEXICO methods and compared with those in the wild type to examine the influence of structural changes and to improve the understanding of this important reaction in studies of protein folding and denaturation. The observed changes follow qualitatively the polarity and steric alterations caused by the introduced amino acids. Attempts to reproduce quantitatively the observed changes by modeling studies and molecular dynamics simulations were not satisfactory. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Induction of Male sterile mutants in vegetable crops

    Energy Technology Data Exchange (ETDEWEB)

    Nagata, Nobuhiko (Hokkaido National Agricultural Experiment Station, Sapporo (Japan))

    1982-03-01

    The cultivars of vegetable crops in Japan are almost all F/sub 1/ hybrid lines. These hybrid cultivars are superior in yield, quality and uniformity by heterosis, and play an important role in the protection of breeder's rights. Utilization of male sterile mutants has such advantages as the reduction of cost for F/sub 1/ production by saving labor, production of better seeds, that is, pollination without emasculation and avoidance of contamination caused by self pollination. Male sterility must be used for some species in which seed production is difficult because of tiny flowers and meager seed production by artificial crossing such as carrot and onion, and those in which pollination by bag or emasculation is expensive such as tomato, and sweet pepper. However, for vegetable crop breeeding, the induction and use of genetic male sterility are more difficult than for other crops, considering the economy and efficiency of research because the type of cultivars needed changes rapidly.

  4. Induction of Male sterile mutants in vegetable crops

    International Nuclear Information System (INIS)

    Nagata, Nobuhiko

    1982-01-01

    The cultivars of vegetable crops in Japan are almost all F 1 hybrid lines. These hybrid cultivars are superior in yield, quality and uniformity by heterosis, and play an important role in the protection of breeder's rights. Utilization of male sterile mutants has such advantages as the reduction of cost for F 1 production by saving labor, production of better seeds, that is, pollination without emasculation and avoidance of contamination caused by self pollination. Male sterility must be used for some species in which seed production is difficult because of tiny flowers and meager seed production by artificial crossing such as carrot and onion, and those in which pollination by bag or emasculation is expensive such as tomato, and sweet pepper. However, for vegetable crop breeeding, the induction and use of genic male sterility are more difficult than for other crops, considering the economy and efficiency of research because the type of cultivars needed changes rapidly. (Kaihara, S.)

  5. A Rice gid1 Suppressor Mutant Reveals That Gibberellin Is Not Always Required for Interaction between Its Receptor, GID1, and DELLA Proteins[W][OA

    Science.gov (United States)

    Yamamoto, Yuko; Hirai, Takaaki; Yamamoto, Eiji; Kawamura, Mayuko; Sato, Tomomi; Kitano, Hidemi; Matsuoka, Makoto; Ueguchi-Tanaka, Miyako

    2010-01-01

    To investigate gibberellin (GA) signaling using the rice (Oryza sativa) GA receptor GIBBERELLIN-INSENSITIVE DWARF1 (GID1) mutant gid1-8, we isolated a suppressor mutant, Suppressor of gid1-1 (Sgd-1). Sgd-1 is an intragenic mutant containing the original gid1-8 mutation (L45F) and an additional amino acid substitution (P99S) in the loop region. GID1P99S interacts with the rice DELLA protein SLENDER RICE1 (SLR1), even in the absence of GA. Substitution of the 99th Pro with other amino acids revealed that substitution with Ala (P99A) caused the highest level of GA-independent interaction. Physicochemical analysis using surface plasmon resonance revealed that GID1P99A has smaller Ka (association) and Kd (dissociation) values for GA4 than does wild-type GID1. This suggests that the GID1P99A lid is at least partially closed, resulting in both GA-independent and GA-hypersensitive interactions with SLR1. One of the three Arabidopsis thaliana GID1s, At GID1b, can also interact with DELLA proteins in the absence of GA, so we investigated whether GA-independent interaction of At GID1b depends on a mechanism similar to that of rice GID1P99A. Substitution of the loop region or a few amino acids of At GID1b with those of At GID1a diminished its GA-independent interaction with GAI while maintaining the GA-dependent interaction. Soybean (Glycine max) and Brassica napus also have GID1s similar to At GID1b, indicating that these unique GID1s occur in various dicots and may have important functions in these plants. PMID:21098733

  6. A rice gid1 suppressor mutant reveals that gibberellin is not always required for interaction between its receptor, GID1, and DELLA proteins.

    Science.gov (United States)

    Yamamoto, Yuko; Hirai, Takaaki; Yamamoto, Eiji; Kawamura, Mayuko; Sato, Tomomi; Kitano, Hidemi; Matsuoka, Makoto; Ueguchi-Tanaka, Miyako

    2010-11-01

    To investigate gibberellin (GA) signaling using the rice (Oryza sativa) GA receptor GIBBERELLIN-INSENSITIVE DWARF1 (GID1) mutant gid1-8, we isolated a suppressor mutant, Suppressor of gid1-1 (Sgd-1). Sgd-1 is an intragenic mutant containing the original gid1-8 mutation (L45F) and an additional amino acid substitution (P99S) in the loop region. GID1(P99S) interacts with the rice DELLA protein SLENDER RICE1 (SLR1), even in the absence of GA. Substitution of the 99th Pro with other amino acids revealed that substitution with Ala (P99A) caused the highest level of GA-independent interaction. Physicochemical analysis using surface plasmon resonance revealed that GID1(P99A) has smaller K(a) (association) and K(d) (dissociation) values for GA(4) than does wild-type GID1. This suggests that the GID1(P99A) lid is at least partially closed, resulting in both GA-independent and GA-hypersensitive interactions with SLR1. One of the three Arabidopsis thaliana GID1s, At GID1b, can also interact with DELLA proteins in the absence of GA, so we investigated whether GA-independent interaction of At GID1b depends on a mechanism similar to that of rice GID1(P99A). Substitution of the loop region or a few amino acids of At GID1b with those of At GID1a diminished its GA-independent interaction with GAI while maintaining the GA-dependent interaction. Soybean (Glycine max) and Brassica napus also have GID1s similar to At GID1b, indicating that these unique GID1s occur in various dicots and may have important functions in these plants.

  7. A new mutant gene su-1 in corn obtained by irradiation with low doses of gamma rays

    International Nuclear Information System (INIS)

    Diaconu, P.

    1993-01-01

    This paper provides a description of a sugar corn mutant obtained by irradiation of wetted kernels of Romanesc de Studina variety with low doses of gamma rays (300 R). This mutant influences the structure of the endosperm similarly to the su-1 genes developed spontaneously which resulted in the corn variety Zea mays saccharata thousands of years ago. Although the mutant is a multiple allele of the su-1 locus in chromosome IV it differs widely from the spontaneous mutant. The length of the ears is much reduced, varying between 4 and 6 cm, with numbers of kernels per ear varying between 45 and 72. Attempts to improve the cob size and the number of kernels by breeding and propagation in an insulated area led to no result. Crossing the mutants with the sugar hybrid Delicious resulted in sugar type progeny which confirms the common position of the mutant gene induced by irradiation and the spontaneous su-1 gene. The progenies of sugar mutant x Delicious are 38-43 % lower in cob vigor and 36-46% lower in kernel number. (author). 2 figs, 2 tab., 16 refs

  8. Reduced starch granule number per chloroplast in the dpe2/phs1 mutant is dependent on initiation of starch degradation.

    Science.gov (United States)

    Malinova, Irina; Fettke, Joerg

    2017-01-01

    An Arabidopsis double knock-out mutant lacking cytosolic disproportionating enzyme 2 (DPE2) and the plastidial phosphorylase (PHS1) revealed a dwarf-growth phenotype, reduced starch content, an uneven distribution of starch within the plant rosette, and a reduced number of starch granules per chloroplast under standard growth conditions. In contrast, the wild type contained 5-7 starch granules per chloroplast. Mature and old leaves of the double mutant were essentially starch free and showed plastidial disintegration. Several analyses revealed that the number of starch granules per chloroplast was affected by the dark phase. So far, it was unclear if it was the dark phase per se or starch degradation in the dark that was connected to the observed decrease in the number of starch granules per chloroplast. Therefore, in the background of the double mutant dpe2/phs1, a triple mutant was generated lacking the initial starch degrading enzyme glucan, water dikinase (GWD). The triple mutant showed improved plant growth, a starch-excess phenotype, and a homogeneous starch distribution. Furthermore, the number of starch granules per chloroplast was increased and was similar to wild type. However, starch granule morphology was only slightly affected by the lack of GWD as in the triple mutant and, like in dpe2/phs1, more spherical starch granules were observed. The characterized triple mutant was discussed in the context of the generation of starch granules and the formation of starch granule morphology.

  9. Morphological and genetic characterization of group I Clostridium botulinum type B strain 111 and the transcriptional regulator spoIIID gene knockout mutant in sporulation.

    Science.gov (United States)

    Hosomi, Koji; Kuwana, Ritsuko; Takamatsu, Hiromu; Kohda, Tomoko; Kozaki, Shunji; Mukamoto, Masafumi

    2015-06-01

    Clostridium botulinum is a heat-resistant spore-forming bacterium that causes the serious paralytic illness botulism. Heat-resistant spores may cause food sanitation hazards and sporulation plays a central role in the survival of C. botulinum. We observed morphological changes and investigated the role of the transcriptional regulator SpoIIID in the sporulation of C. botulinum type B strain 111 in order to elucidate the molecular mechanism in C. botulinum. C. botulinum type B formed heat-resistant spores through successive morphological changes corresponding to those of Bacillus subtilis, a spore-forming model organism. An analysis of the spoIIID gene knockout mutant revealed that the transcriptional regulator SpoIIID contributed to heat-resistant spore formation by C. botulinum type B and activated the transcription of the sigK gene later during sporulation. Transcription of the spoIIID gene, which differed from that in B. subtilis and Clostridium difficile, was observed in the sigE gene knockout mutant of C. botulinum type B. An analysis of the sigF gene knockout mutant showed that the sporulation-specific sigma factor SigF was essential for transcription of the spoIIID gene in C. botulinum type B. These results suggest that the regulation of sporulation in C. botulinum is not similar to that in B. subtilis and other clostridia. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Search for C4 developmental mutants in Panicum maximum Jacq

    International Nuclear Information System (INIS)

    Fladung, M.

    2001-01-01

    Full text: Mutant plants are useful tools for studying developmental processes in defined genetic backgrounds by comparing them with their respective wild type forms. In this sense, developmental mutants or mutations involved in the establishment of certain leaf or flower specific traits are of special interest. In particular, the evolution of C 4 photosynthesis from C 3 precursors was accompanied by severe developmental changes in leaf morphology and anatomy. Our search of such mutants was followed by the idea to approach the evolution of the C 4 syndrome from a mutagenic point of view. Variants affecting normal development of the C 4 leaf anatomy may, in fact, represent possible regressive steps in C4 photosynthesis. Seeds of the C4 grass Panicum maximum Jacq. were mutagenized using ethylmethanesulfonate (EMS) and putative variants were isolated in the M2 generation by visual inspection. Main selection characteristics were whole plant, leaf morphology and pigmentation, and growth characteristics. The choice of a polyploid species for mutagenesis experiments was based on the need of detecting rare mutants, which are possibly lethal when using a diploid plant species. These variants could be of regulatory nature, affecting both morphology and physiology of C 4 photosynthesis early in leaf development. In total, nearly 100 variants were isolated and grown to maturity. Main isolated variants, which conforms to the prediction mentioned above, were as following: large interveinal space-1 and -3 (lis1, lis3), abnormal bundle sheath (abs), midribless (mbl) and variegated leaf -1 (var1). The variant lis1 was a short plant with leaves smaller than the wild type, and had a leaf lamina with a crinkly surface. Photosynthetically, lis1 indicates a clear regression from the C 4 to the C 3 photosynthesis type, which was correlated in the leaf lamina with an increase in the distance between small veins. The variant lis3 was not similar phenotypically to lis1, but it also had very

  11. Gamma-radiation Mutagenesis in Genetically Unstable Barley Mutants. Pt. 1. Chlorophyll Mutations in Allelic tw Mutants and Their Revertants

    International Nuclear Information System (INIS)

    Vaitkuniene, V.

    1995-01-01

    Genotypical environment is an essential factor determining the mutability of mutants of the same type. Decreased chlorophyll mutant frequency was a common characteristic of all tested tw type (tw, tw 1 , tw 2 ) mutants induced in barley c. 'Auksiniai II'. The mutability of all the tested revertants was close to that of the initial c. 'Auksiniai II'. (author). 9 refs., 2 tabs

  12. Alaska, Gulf spills share similarities

    International Nuclear Information System (INIS)

    Usher, D.

    1991-01-01

    The accidental Exxon Valdez oil spill in Alaska and the deliberate dumping of crude oil into the Persian Gulf as a tactic of war contain both glaring differences and surprising similarities. Public reaction and public response was much greater to the Exxon Valdez spill in pristine Prince William Sound than to the war-related tragedy in the Persian Gulf. More than 12,000 workers helped in the Alaskan cleanup; only 350 have been involved in Kuwait. But in both instances, environmental damages appear to be less than anticipated. Natures highly effective self-cleansing action is primarily responsible for minimizing the damages. One positive action growing out of the two incidents is increased international cooperation and participation in oil-spill clean-up efforts. In 1990, in the aftermath of the Exxon Valdez spill, 94 nations signed an international accord on cooperation in future spills. The spills can be historic environmental landmarks leading to creation of more sophisticated response systems worldwide

  13. TDP-43 causes differential pathology in neuronal versus glial cells in the mouse brain.

    Science.gov (United States)

    Yan, Sen; Wang, Chuan-En; Wei, Wenjie; Gaertig, Marta A; Lai, Liangxue; Li, Shihua; Li, Xiao-Jiang

    2014-05-15

    Mutations in TAR DNA-binding protein 43 (TDP-43) are associated with familial forms of amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Although recent studies have revealed that mutant TDP-43 in neuronal and glial cells is toxic, how mutant TDP-43 causes primarily neuronal degeneration in an age-dependent manner remains unclear. Using adeno-associated virus (AAV) that expresses mutant TDP-43 (M337V) ubiquitously, we found that mutant TDP-43 accumulates preferentially in neuronal cells in the postnatal mouse brain. We then ubiquitously or selectively expressed mutant TDP-43 in neuronal and glial cells in the striatum of adult mouse brains via stereotaxic injection of AAV vectors and found that it also preferentially accumulates in neuronal cells. Expression of mutant TDP-43 in neurons in the striatum causes more severe degeneration, earlier death and more robust symptoms in mice than expression of mutant TDP-43 in glial cells; however, aging increases the expression of mutant TDP-43 in glial cells, and expression of mutant TDP-43 in older mice caused earlier onset of phenotypes and more severe neuropathology than that in younger mice. Although expression of mutant TDP-43 in glial cells via stereotaxic injection does not lead to robust neurological phenotypes, systemic inhibition of the proteasome activity via MG132 in postnatal mice could exacerbate glial TDP-43-mediated toxicity and cause mice to die earlier. Consistently, this inhibition increases the expression of mutant TDP-43 in glial cells in mouse brains. Thus, the differential accumulation of mutant TDP-43 in neuronal versus glial cells contributes to the preferential toxicity of mutant TDP-43 in neuronal cells and age-dependent pathology.

  14. Meiosis observation of the sterile mutant after injection of exogenous DNA into wheat

    International Nuclear Information System (INIS)

    Yang Jingcheng; Yu Yuanjie; Qi Yanfang; Shen Fafu; Liu Fengzhen

    2001-01-01

    A male sterile mutant was obtained after injection of exogenous λ DNA into wheat line 814527. Meiosis of pollen mother cells (PMC) of the mutant and its receptor (line 814527) were observed. The results showed that the frequency of chromosomal variation of the sterile line was 18%, and that of the receptor was 0.8%. The main types of variation included univalent, chromosome lagging, chromosome fragment, chromosome bridge, micronucleus, abnormal ditrad and tetrad. The fragment of DNA injected into the receptor may influence the normal genetic process of chromosomes in pollen mother cells, and this may cause variations of chromosomes. The chromosome variation in meiosis may cause a part of pollen mother cells to abort, but it is not the main cause of abortion

  15. High yielding mutants of blackgram variety 'PH-25'

    International Nuclear Information System (INIS)

    Misra, R.C.; Mohapatra, B.D.; Panda, B.S.

    2001-01-01

    Seeds of blackgram (Vigna mungo L.) variety 'PH-5' were treated with chemical mutagens ethyl methanesulfonate (EMS), nitrosoguanidine (NG), maleic hydrazide (MH) and sodium azide (NaN 3 ), each at 3 different concentrations. Thirty six mutant lines developed from mutagenic treatments along with parent varieties were tested in M 4 generation. The mutants showed wide variation in most of the traits and multivariante D 2 analysis showed genetic divergence among themselves. Twenty of the thirty mutants showed genetic divergence from parent. Ten selected high yielding mutants were tested in M 5 . Yield and other productive traits of five high yielding mutants in M 4 and M 5 are presented

  16. Evidence for Genetic Similarity of Vegetative Compatibility Groupings in Sclerotinia homoeocarpa

    Directory of Open Access Journals (Sweden)

    Seog Won Chang

    2014-12-01

    Full Text Available Vegetative compatibility groups (VCGs are determined for many fungi to test for the ability of fungal isolates to undergo heterokaryon formation. In several fungal plant pathogens, isolates belonging to a VCG have been shown to share significantly higher genetic similarity than those of different VCGs. In this study we sought to examine the relationship between VCG and genetic similarity of an important cool season turfgrass pathogen, Sclerotinia homoeocarpa. Twenty-two S. homoeocarpa isolates from the Midwest and Eastern US, which were previously characterized in several studies, were all evaluated for VCG using an improved nit mutant assay. These isolates were also genotyped using 19 microsatellites developed from partial genome sequence of S. homoeocarpa. Additionally, partial sequences of mitochondrial genes cytochrome oxidase II and mitochondrial small subunit (mtSSU rRNA, and the atp6-rns intergenic spacer, were generated for isolates from each nit mutant VCG to determine if mitochondrial haplotypes differed among VCGs. Of the 22 isolates screened, 15 were amenable to the nit mutant VCG assay and were grouped into six VCGs. The 19 microsatellites gave 57 alleles for this set. Unweighted pair group methods with arithmetic mean (UPGMA tree of binary microsatellite data were used to produce a dendrogram of the isolate genotypes based on microsatellite alleles, which showed high genetic similarity of nit mutant VCGs. Analysis of molecular variance of microsatellite data demonstrates that the current nit mutant VCGs explain the microsatellite genotypic variation among isolates better than the previous nit mutant VCGs or the conventionally determined VCGs. Mitochondrial sequences were identical among all isolates, suggesting that this marker type may not be informative for US populations of S. homoeocarpa.

  17. Self-similar analysis of the spherical implosion process

    International Nuclear Information System (INIS)

    Ishiguro, Yukio; Katsuragi, Satoru.

    1976-07-01

    The implosion processes caused by laser-heating ablation has been studied by self-similarity analysis. Attention is paid to the possibility of existence of the self-similar solution which reproduces the implosion process of high compression. Details of the self-similar analysis are reproduced and conclusions are drawn quantitatively on the gas compression by a single shock. The compression process by a sequence of shocks is discussed in self-similarity. The gas motion followed by a homogeneous isentropic compression is represented by a self-similar motion. (auth.)

  18. Aggregation of ALS-linked FUS mutant sequesters RNA binding proteins and impairs RNA granules formation

    Energy Technology Data Exchange (ETDEWEB)

    Takanashi, Keisuke; Yamaguchi, Atsushi, E-mail: atsyama@restaff.chiba-u.jp

    2014-09-26

    Highlights: • Aggregation of ALS-linked FUS mutant sequesters ALS-associated RNA-binding proteins (FUS wt, hnRNP A1, and hnRNP A2). • Aggregation of ALS-linked FUS mutant sequesters SMN1 in the detergent-insoluble fraction. • Aggregation of ALS-linked FUS mutant reduced the number of speckles in the nucleus. • Overproduced ALS-linked FUS mutant reduced the number of processing-bodies (PBs). - Abstract: Protein aggregate/inclusion is one of hallmarks for neurodegenerative disorders including amyotrophic lateral sclerosis (ALS). FUS/TLS, one of causative genes for familial ALS, encodes a multifunctional DNA/RNA binding protein predominantly localized in the nucleus. C-terminal mutations in FUS/TLS cause the retention and the inclusion of FUS/TLS mutants in the cytoplasm. In the present study, we examined the effects of ALS-linked FUS mutants on ALS-associated RNA binding proteins and RNA granules. FUS C-terminal mutants were diffusely mislocalized in the cytoplasm as small granules in transiently transfected SH-SY5Y cells, whereas large aggregates were spontaneously formed in ∼10% of those cells. hnRNP A1, hnRNP A2, and SMN1 as well as FUS wild type were assembled into stress granules under stress conditions, and these were also recruited to FUS mutant-derived spontaneous aggregates in the cytoplasm. These aggregates stalled poly(A) mRNAs and sequestered SMN1 in the detergent insoluble fraction, which also reduced the number of nuclear oligo(dT)-positive foci (speckles) in FISH (fluorescence in situ hybridization) assay. In addition, the number of P-bodies was decreased in cells harboring cytoplasmic granules of FUS P525L. These findings raise the possibility that ALS-linked C-terminal FUS mutants could sequester a variety of RNA binding proteins and mRNAs in the cytoplasmic aggregates, which could disrupt various aspects of RNA equilibrium and biogenesis.

  19. Mutant p53 interactions with supercoiled DNA

    Czech Academy of Sciences Publication Activity Database

    Brázdová, Marie; Němcová, Kateřina; Činčárová, Lenka; Šebest, Peter; Pivoňková, Hana; Brázda, Václav; Fojta, Miroslav; Paleček, Emil

    2007-01-01

    Roč. 24, č. 6 (2007), s. 639-640 ISSN 0739-1102. [Alban 2007: The 15th Conversation . 19.06.2007-23.06.2007, Albany] R&D Projects: GA MŠk(CZ) 1K04119; GA ČR(CZ) GP204/06/P369; GA MŠk(CZ) LC06035 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : mutant p53 * supercoiled DNA * cancer Subject RIV: BO - Biophysics

  20. Radiation induced desynaptic mutants in barley

    International Nuclear Information System (INIS)

    Srivastava, H.M.

    1974-01-01

    Spontaneous occurrence of asynapsis and desynapsis has been frequently reported in a number of crop plants (Beadle 1930, 1933; Beasley and Brown 1942; Li et al. 1945; Magoon et al. 1961; Miller 1963) and other angiospermic texa (Calarier 1955; Chennaveraiah and Krisnappa 1968; Ehrenberg 1949; Johnson 1941, 1944; Roy and Jha 1958). However, there are only a few reports of induced asynapsis or desynapsis (Gottschalk and Baquar 1971; Martini and Bozzini 1966). The present paper deals with the morphology and meiotic behavior of gamma-ray induced barley mutants showing high degree of desynapsis resulting in partial to complete sterility. (author)

  1. Mutant spectra of irradiated CHO AL cells determined with multiple markers analyzed by flow cytometry

    International Nuclear Information System (INIS)

    Ross, Carley D.; French, C. Tenley; Keysar, Stephen B.; Fox, Michael H.

    2007-01-01

    We have previously developed a sensitive and rapid mammalian cell mutation assay which is based on a Chinese hamster ovary cell line that stably incorporates human chromosome 11 (CHO A L ) and uses flow cytometry to measure mutations in CD59. We now show that multiparameter flow cytometry may be used to simultaneously analyze irradiated CHO A L cells for mutations in five CD genes along chromosome 11 (CD59, CD44, CD90, CD98, CD151) and also a GPI-anchor gene. Using this approach, 19 different mutant clones derived from individual sorted mutant cells were analyzed to determine the mutant spectrum induced by ionizing radiation. All clones analyzed were negative for CD59 expression and PCR confirmed that at least CD59 exon 4 was also absent. As expected, ionizing radiation frequently caused large deletions along chromosome 11. This technology can readily be used to rapidly analyze the mutant yield as well as the spectrum of mutations caused by a variety of genotoxic agents and provide greater insight into the mechanisms of mutagenesis

  2. Data supporting mitochondrial morphological changes by SPG13-associated HSPD1 mutants

    Directory of Open Access Journals (Sweden)

    Yuki Miyamoto

    2016-03-01

    Full Text Available The data is related to the research article entitled “Hypomyelinating leukodystrophy-associated missense mutation in HSPD1 blunts mitochondrial dynamics” [1]. In addition to hypomyelinating leukodystrophy (HLD 4 (OMIM no. 612233, it is known that spastic paraplegia (SPG 13 (OMIM no. 605280 is caused by HSPD1’s amino acid mutation. Two amino acid mutations Val-98-to-Ile (V98I and Gln-461-to-Glu (Q461E are associated with SPG13 [2]. In order to investigate the effects of HSPD1’s V98I or Q461E mutant on mitochondrial morphological changes, we transfected each of the respective mutant-encoding genes into Cos-7 cells. Either of V98I or Q461E mutant exhibited increased number of mitochondria and short length mitochondrial morphologies. Using MitoTracker dye-incorporating assay, decreased mitochondrial membrane potential was also observed in both cases. The data described here supports that SPG13-associated HSPD1 mutant participates in causing aberrant mitochondrial morphological changes with decreased activities. Keywords: SPG13, HSPD1, Mitochondrion, Morphological change

  3. Autophagy and UPR in alpha-crystallin mutant knock-in mouse models of hereditary cataracts.

    Science.gov (United States)

    Andley, Usha P; Goldman, Joshua W

    2016-01-01

    Knock-in mice provide useful models of congenital and age-related cataracts caused by α-crystallin mutations. R49C αA-crystallin and R120G αB-crystallin mutations are linked with hereditary cataracts. Knock-in αA-R49C+/- heterozygotes develop cataracts by 1-2months, whereas homozygote mice have cataracts at birth. The R49C mutation drastically reduces lens protein water solubility and causes cell death in knock-in mouse lenses. Mutant crystallin cannot function as a chaperone, which leads to protein aggregation and lens opacity. Protein aggregation disrupts the lens fiber cell structure and normal development and causes cell death in epithelial and fiber cells. We determined what aspects of the wild-type phenotype are age-dependently altered in the mutant lens. Wild-type, heterozygote (αA-R49C+/-), and homozygote (αA-R49C+/+) mouse lenses were assessed pre- and postnatally for lens morphology (electron microscopy, immunohistochemistry), and autophagy or unfolded protein response markers (immunoblotting). Morphology was altered by embryonic day 17 in R49C+/+ lenses; R49C+/- lens morphology was unaffected at this stage. Active autophagy in the lens epithelium of mutant lenses was indicated by the presence of autophagosomes using electron microscopy. Protein p62 levels, which are degraded specifically by autophagy, increased in αA-R49C mutant versus wild-type lenses, suggesting autophagy inhibition in the mutant lenses. The unfolded protein response marker XBP-1 was upregulated in adult lenses of αB-R120G+/+ mice, suggesting its role in lens opacification. Mutated crystallins alter lens morphology, autophagy, and stress responses. Therapeutic modulation of autophagic pathways may improve protein degradation in cataractous lenses and reduce lens opacity. This article is part of a Special Issue entitled Crystallin Biochemistry in Health and Disease. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. TNF Lectin-Like Domain Restores Epithelial Sodium Channel Function in Frameshift Mutants Associated with Pseudohypoaldosteronism Type 1B

    Directory of Open Access Journals (Sweden)

    Anita Willam

    2017-05-01

    Full Text Available Previous in vitro studies have indicated that tumor necrosis factor (TNF activates amiloride-sensitive epithelial sodium channel (ENaC current through its lectin-like (TIP domain, since cyclic peptides mimicking the TIP domain (e.g., solnatide, showed ENaC-activating properties. In the current study, the effects of TNF and solnatide on individual ENaC subunits or ENaC carrying mutated glycosylation sites in the α-ENaC subunit were compared, revealing a similar mode of action for TNF and solnatide and corroborating the previous assumption that the lectin-like domain of TNF is the relevant molecular structure for ENaC activation. Accordingly, TNF enhanced ENaC current by increasing open probability of the glycosylated channel, position N511 in the α-ENaC subunit being identified as the most important glycosylation site. TNF significantly increased Na+ current through ENaC comprising only the pore forming subunits α or δ, was less active in ENaC comprising only β-subunits, and showed no effect on ENaC comprising γ-subunits. TNF did not increase the membrane abundance of ENaC subunits to the extent observed with solnatide. Since the α-subunit is believed to play a prominent role in the ENaC current activating effect of TNF and TIP, we investigated whether TNF and solnatide can enhance αβγ-ENaC current in α-ENaC loss-of-function frameshift mutants. The efficacy of solnatide has been already proven in pathological conditions involving ENaC in phase II clinical trials. The frameshift mutations αI68fs, αT169fs, αP197fs, αE272fs, αF435fs, αR438fs, αY447fs, αR448fs, αS452fs, and αT482fs have been reported to cause pseudohypoaldosteronism type 1B (PHA1B, a rare, life-threatening, salt-wasting disease, which hitherto has been treated only symptomatically. In a heterologous expression system, all frameshift mutants showed significantly reduced amiloride-sensitive whole-cell current compared to wild type αβγ-ENaC, whereas membrane

  5. Drought resistant rice mutants, characteristics and discussions on possibilities for planting them in some Arab Countries which import rice

    International Nuclear Information System (INIS)

    Abo-Hegazi, A.M.T.

    1994-01-01

    A number of drought resistant mutants of rice were produced from ordinary rice varieties being planted in several parts of Egypt through utilization of gamma rays as a mutagen. The mutants have water requirements less than one half of that of their mother varieties. According to official data, authorities in Egypt insure about 18000 M 3 of irrigation water for every hectare (10000 M 2 ) of rice and about 6700 M 3 , 6900 M 3 for every hectare of corn and ground nuts, respectively. Peanuts and corn are summer crops like the drought resistant rice mutants. The mentioned mutants can produce good yield under water requirements very near to that of corn and peanuts. The wide gap in agricultural food stuffs for the Arab Countries (more than 20000 million US $ annually) includes rice imports usually exceeds 700 million US $ per year> Rice imports of Arab Countries such as Saudi Arabia, Yemen, Syria, Libya and the Sudan, reached 180, 47, 21, 16 and 14 million US $ in 1988 as an example. Such countries could make use of the drought resistant rice mutants for plantation on water requirements very near to those of usual summer crops such as corn and peanuts which is significantly less than one half of water requirements of their mother varieties. Some characteristics of such mutants as well as discussions on possibilities for planting them in some of the nominated Arab Countries are presented. However, arrangements for ensuring the minimum water requirements during the growing period irrespective to rain which in many cases did not accord the growing period of the mutants should be taken if such countries wants to make use of the drought resistant rice mutants. The author believe that most if not all requirements of rice of such countries could locally be ensured through planting of the above mentioned rice mutants. In this case, maximizing the efficiency of utilizing the limited water resources of such countries could also be counted as another cause for presenting this

  6. Further studies on O2-resistant photosynthesis and photorespiration in a tobacco mutant with enhanced catalase activity

    International Nuclear Information System (INIS)

    Zelitch, I.

    1990-01-01

    The increase in net photosynthesis in M 4 progeny of an O 2 -resistant tobacco (Nicotiana tabacum) mutant relative to wild-type plants at 21 and 42% O 2 has been confirmed and further investigated. Self-pollination of an M 3 mutant produced M 4 progeny segregating high catalase phenotypes (average 40% greater than wild type) at a frequency of about 60%. The high catalase phenotype cosegregated precisely with O 2 -resistant photosynthesis. About 25% of the F 1 progeny of reciprocal crosses between the same M 3 mutant and wild type had high catalase activity, whether the mutant was used as the maternal or paternal parent, indicating nuclear inheritance. In high-catalase mutants the activity of NADH-hydroxypyruvate reductase, another peroxisomal enzyme, was the same as wild type. The mutants released 15% less photorespiratory CO 2 as a percent of net photosynthesis in CO 2 -free 21% O 2 and 36% less in CO 2 -free 42% O 2 compared with wild type. The mutant leaf tissue also released less 14 CO 2 per [1- 14 C]glycolate metabolized than wild type in normal air, consistent with less photorespiration in the mutant. The O 2 -resistant photosynthesis appears to be caused by a decrease in photorespiration especially under conditions of high O 2 where the stoichiometry of CO 2 release per glycolate metabolized is expected to be enhanced. The higher catalase activity in the mutant may decrease the nonenzymatic peroxidation of keto-acids such as hydroxypyruvate and glyoxylate by photorespiratory H 2 O 2

  7. Brucellosis vaccines: assessment of Brucella melitensis lipopolysaccharide rough mutants defective in core and O-polysaccharide synthesis and export.

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    David González

    Full Text Available BACKGROUND: The brucellae are facultative intracellular bacteria that cause brucellosis, one of the major neglected zoonoses. In endemic areas, vaccination is the only effective way to control this disease. Brucella melitensis Rev 1 is a vaccine effective against the brucellosis of sheep and goat caused by B. melitensis, the commonest source of human infection. However, Rev 1 carries a smooth lipopolysaccharide with an O-polysaccharide that elicits antibodies interfering in serodiagnosis, a major problem in eradication campaigns. Because of this, rough Brucella mutants lacking the O-polysaccharide have been proposed as vaccines. METHODOLOGY/PRINCIPAL FINDINGS: To examine the possibilities of rough vaccines, we screened B. melitensis for lipopolysaccharide genes and obtained mutants representing all main rough phenotypes with regard to core oligosaccharide and O-polysaccharide synthesis and export. Using the mouse model, mutants were classified into four attenuation patterns according to their multiplication and persistence in spleens at different doses. In macrophages, mutants belonging to three of these attenuation patterns reached the Brucella characteristic intracellular niche and multiplied intracellularly, suggesting that they could be suitable vaccine candidates. Virulence patterns, intracellular behavior and lipopolysaccharide defects roughly correlated with the degree of protection afforded by the mutants upon intraperitoneal vaccination of mice. However, when vaccination was applied by the subcutaneous route, only two mutants matched the protection obtained with Rev 1 albeit at doses one thousand fold higher than this reference vaccine. These mutants, which were blocked in O-polysaccharide export and accumulated internal O-polysaccharides, stimulated weak anti-smooth lipopolysaccharide antibodies. CONCLUSIONS/SIGNIFICANCE: The results demonstrate that no rough mutant is equal to Rev 1 in laboratory models and question the notion that

  8. Induction of drought tolerant mutants of rice

    International Nuclear Information System (INIS)

    El-Hissewy, A.A.; Abd Allah, A.

    2001-01-01

    The ultimate goal of crop breeding is to develop varieties with a high yield potential and desirable agronomic characteristics. In Egypt, the most important qualities sought by breeders have been high yield potential, resistance to major diseases and insects, and improved grain and eating quality. However, breeding efforts should concentrate on varieties with the potential to minimize yield losses under unfavorable conditions such as drought, and to maximize yields when conditions are favorable. Rice (Oryza sativa L.) in Egypt is completely irrigated and a significant portion of the rice cultivated area is subject to water deficit resulting from an inadequate or insufficient irrigation supply. Drought tolerance is a complex trait in that it results from the interaction of histological and physiological characters of plant with environmental factors, both above-ground and under-ground. Accordingly, root characters are closely related to drought tolerance. Little attention has been paid in Egyptian breeding programs to root characters and their relation to shoot characters. Furthermore, induced mutations are considered as one of the most important methods to induce useful mutants, especially with improved root characters, to overcome the drought problem. The present investigation aimed to study the effect of different doses of gamma rays on several characters of three Egyptian rice varieties, i.e. 'Giza 171', 'Giza 175' and 'Giza 176' and to induce one or more mutants possessing drought tolerance

  9. Flower morphology of Dendrobium Sonia mutants

    International Nuclear Information System (INIS)

    Sakinah Ariffin; Azhar Mohamad; Affrida Abu Hassan; Zaiton Ahmad; Mohd Nazir Basiran

    2010-01-01

    Dendrobium Sonia is a commercial hybrid which is popular as cut flower and potted plant in Malaysia. Variability in flower is important for new variety to generate more demands and choices in selection. Mutation induction is a tool in creating variability for new flower color and shape. In vitro cultures of protocorm-like bodies (PLBs) were exposed to gamma ray at dose 35 Gy. Phenotypic characteristics of the flower were observed at fully bloomed flower with emphasis on shape and color. Approximately 2000 regenerated irradiated plants were observed and after subsequent flowering, 100 plants were finally selected for further evaluation. Most of the color and shape changes are expressed in different combinations of petal, sepal and lip of the flower. In this work, 11 stable mutants were found different at flower phenotype as compared to control. Amongst these, four mutant varieties with commercial potential has been named as Dendrobium 'SoniaKeenaOval', Dendrobium 'SoniaKeenaRadiant', Dendrobium 'SoniaKeenaHiengDing' and Dendrobium 'Sonia KeenaAhmadSobri'. In this paper, variations in flower morphology and flower color were discussed, giving emphasis on variations in flower petal shape. (author)

  10. High yielding rice mutants for West Bengal

    International Nuclear Information System (INIS)

    Debnath, A.R.; Sen, S.

    1980-01-01

    Four high yielding mutants with specific genetic corrections of the simply inherited characters were developed from IR-8 through X-irradiation. Recurrent selections of the promising isolates were made under diverse agro-climatic conditions in Winter and Summer seasons of West Bengal. The isolates CNM 6 and CNM 25 belonging to early maturity group and CNM 20 and CNM 31, to mid-early maturity group were finally selected at X 5 generation on the basis of their resistance qualities, maturity period and grain yield. They were evaluated upto X 10 qeneration at multi-locations as Pre-release and Minikit Varieties at State level. They were also placed at the National Screening Nursery (NSN) for screening against multiple diseases and pests at the National level. CNM 6 is reported to be promising in IRTP nurseries. It is reported that CNM 25 (IET 5646) ranked 2nd on the basis of average grain yield, CNM 20 (IET 5937) and CNM 31 (IET 5936) were resistant to diseases and with yield comparable to Jaya. These four productive mutants of superior types are widely accepted. CNM 6 is recommended for cultivation in Bankura and Birbhum districts and CNM 25 and CNM 31 in the different agro-climatic zones of West Bengal. (author)

  11. Shallow Boomerang-shaped Influenza Hemagglutinin G13A Mutant Structure Promotes Leaky Membrane Fusion*

    Science.gov (United States)

    Lai, Alex L.; Tamm, Lukas K.

    2010-01-01

    Our previous studies showed that an angled boomerang-shaped structure of the influenza hemagglutinin (HA) fusion domain is critical for virus entry into host cells by membrane fusion. Because the acute angle of ∼105° of the wild-type fusion domain promotes efficient non-leaky membrane fusion, we asked whether different angles would still support fusion and thus facilitate virus entry. Here, we show that the G13A fusion domain mutant produces a new leaky fusion phenotype. The mutant fusion domain structure was solved by NMR spectroscopy in a lipid environment at fusion pH. The mutant adopted a boomerang structure similar to that of wild type but with a shallower kink angle of ∼150°. G13A perturbed the structure of model membranes to a lesser degree than wild type but to a greater degree than non-fusogenic fusion domain mutants. The strength of G13A binding to lipid bilayers was also intermediate between that of wild type and non-fusogenic mutants. These membrane interactions provide a clear link between structure and function of influenza fusion domains: an acute angle is required to promote clean non-leaky fusion suitable for virus entry presumably by interaction of the fusion domain with the transmembrane domain deep in the lipid bilayer. A shallower angle perturbs the bilayer of the target membrane so that it becomes leaky and unable to form a clean fusion pore. Mutants with no fixed boomerang angle interacted with bilayers weakly and did not promote any fusion or membrane perturbation. PMID:20826788

  12. Enhanced hippocampal long-term potentiation and fear memory in Btbd9 mutant mice.

    Directory of Open Access Journals (Sweden)

    Mark P DeAndrade

    Full Text Available Polymorphisms in BTBD9 have recently been associated with higher risk of restless legs syndrome (RLS, a neurological disorder characterized by uncomfortable sensations in the legs at rest that are relieved by movement. The BTBD9 protein contains a BTB/POZ domain and a BACK domain, but its function is unknown. To elucidate its function and potential role in the pathophysiology of RLS, we generated a line of mutant Btbd9 mice derived from a commercial gene-trap embryonic stem cell clone. Btbd9 is the mouse homolog of the human BTBD9. Proteins that contain a BTB/POZ domain have been reported to be associated with synaptic transmission and plasticity. We found that Btbd9 is naturally expressed in the hippocampus of our mutant mice, a region critical for learning and memory. As electrophysiological characteristics of CA3-CA1 synapses of the hippocampus are well characterized, we performed electrophysiological recordings in this region. The mutant mice showed normal input-output relationship, a significant impairment in pre-synaptic activity, and an enhanced long-term potentiation. We further performed an analysis of fear memory and found the mutant mice had an enhanced cued and contextual fear memory. To elucidate a possible molecular basis for these enhancements, we analyzed proteins that have been associated with synaptic plasticity. We found an elevated level of dynamin 1, an enzyme associated with endocytosis, in the mutant mice. These results suggest the first identified function of Btbd9 as being involved in regulating synaptic plasticity and memory. Recent studies have suggested that enhanced synaptic plasticity, analogous to what we have observed, in other regions of the brain could enhance sensory perception similar to what is seen in RLS patients. Further analyses of the mutant mice will help shine light on the function of BTBD9 and its role in RLS.

  13. Enhanced hippocampal long-term potentiation and fear memory in Btbd9 mutant mice.

    Science.gov (United States)

    DeAndrade, Mark P; Zhang, Li; Doroodchi, Atbin; Yokoi, Fumiaki; Cheetham, Chad C; Chen, Huan-Xin; Roper, Steven N; Sweatt, J David; Li, Yuqing

    2012-01-01

    Polymorphisms in BTBD9 have recently been associated with higher risk of restless legs syndrome (RLS), a neurological disorder characterized by uncomfortable sensations in the legs at rest that are relieved by movement. The BTBD9 protein contains a BTB/POZ domain and a BACK domain, but its function is unknown. To elucidate its function and potential role in the pathophysiology of RLS, we generated a line of mutant Btbd9 mice derived from a commercial gene-trap embryonic stem cell clone. Btbd9 is the mouse homolog of the human BTBD9. Proteins that contain a BTB/POZ domain have been reported to be associated with synaptic transmission and plasticity. We found that Btbd9 is naturally expressed in the hippocampus of our mutant mice, a region critical for learning and memory. As electrophysiological characteristics of CA3-CA1 synapses of the hippocampus are well characterized, we performed electrophysiological recordings in this region. The mutant mice showed normal input-output relationship, a significant impairment in pre-synaptic activity, and an enhanced long-term potentiation. We further performed an analysis of fear memory and found the mutant mice had an enhanced cued and contextual fear memory. To elucidate a possible molecular basis for these enhancements, we analyzed proteins that have been associated with synaptic plasticity. We found an elevated level of dynamin 1, an enzyme associated with endocytosis, in the mutant mice. These results suggest the first identified function of Btbd9 as being involved in regulating synaptic plasticity and memory. Recent studies have suggested that enhanced synaptic plasticity, analogous to what we have observed, in other regions of the brain could enhance sensory perception similar to what is seen in RLS patients. Further analyses of the mutant mice will help shine light on the function of BTBD9 and its role in RLS.

  14. Competitive Interactions Between Incompatible Mutants of the Social Bacterium Myxococcus xanthus DK1622

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    Ya Gong

    2018-06-01

    Full Text Available Due to the high similarity in their requirements for space and food, close bacterial relatives may be each other's strongest competitors. Close bacterial relatives often form visible boundaries to separate their swarming colonies, a phenomenon termed colony-merger incompatibility. While bacterial species are known to have many incompatible strains, it is largely unclear which traits lead to multiple incompatibilities and the interactions between multiple incompatible siblings. To investigate the competitive interactions of closely related incompatible strains, we mutated Myxococcus xanthus DK1622, a predatory bacterium with complex social behavior. From 3392 random transposon mutations, we obtained 11 self-identification (SI deficient mutants that formed unmerged colony boundaries with the ancestral strain. The mutations were at nine loci with unknown functions and formed nine independent SI mutants. Compared with their ancestral strain, most of the SI mutants showed reduced growth, swarming and development abilities, but some remained unchanged from their monocultures. When pairwise mixed with their ancestral strain for co-cultivation, these mutants exhibited improved, reduced or unchanged competitive abilities compared with the ancestral strain. The sporulation efficiencies were affected by the DK1622 partner, ranging from almost complete inhibition to 360% stimulation. The differences in competitive growth between the SI mutants and DK1622 were highly correlated with the differences in their sporulation efficiencies. However, the competitive efficiencies of the mutants in mixture were inconsistent with their growth or sporulation abilities in monocultures. We propose that the colony-merger incompatibility in M. xanthus is associated with multiple independent genetic loci, and the incompatible strains hold competitive interaction abilities, which probably determine the complex relationships between multiple incompatible M. xanthus strains and

  15. Ligand and proton exchange dynamics in recombinant human myoglobin mutants.

    Science.gov (United States)

    Lambright, D G; Balasubramanian, S; Boxer, S G

    1989-05-05

    Site-specific mutants of human myoglobin have been prepared in which lysine 45 is replaced by arginine (K45R) and aspartate 60 by glutamate (D60E), in order to examine the influence of these residues and their interaction on the dynamics of the protein. These proteins were studied by a variety of methods, including one and two-dimensional proton nuclear magnetic resonance spectroscopy, exchange kinetics for the distal and proximal histidine NH protons as a function of pH in the met cyano forms, flash photolysis of the CO forms, and ligand replacement kinetics. The electronic absorption and proton nuclear magnetic resonance spectra of the CO forms of these proteins are virtually identical, indicating that the structure of the heme pocket is unaltered by these mutations. There are, however, substantial changes in the dynamics of both CO binding and proton exchange for the mutant K45R, whereas the mutant D60E exhibits behavior indistinguishable from the reference human myoglobin. K45R has a faster CO bimolecular recombination rate and slower CO off-rate relative to the reference. The kinetics for CO binding are independent of pH (6.5 to 10) as well as ionic strength (0 to 1 M-NaCl). The exchange rate for the distal histidine NH is substantially lower for K45R than the reference, whereas the proximal histidine NH exchange rate is unaltered. The exchange behavior of the human proteins is similar to that reported for a comparison of the exchange rates for myoglobins having lysine at position 45 with sperm whale myoglobin, which has arginine at this position. This indicates that the differences in exchange rates reflects largely the Lys----Arg substitution. The lack of a simple correlation for the CO kinetics with this substitution means that these are sensitive to other factors as well. Specific kinetic models, whereby substitution of arginine for lysine at position 45 can affect ligand binding dynamics, are outlined. These experiments demonstrate that a relatively

  16. Serrated leaf mutant in mungbean (Vigna radiata (L) Wilczek)

    International Nuclear Information System (INIS)

    Malik, I.A.; Ghulam, Sarwar; Yousaf, Ali; Saleem, M.

    1988-01-01

    Dry dormant seeds of mungbean (Vigna radiata (L) Wilczek) were treated with gamma rays (15, 30 and 60 kR). The serrated leaf mutation was noticed in M 2 of cultivar Pak 32 treated with 60 kR. Cf 14 plants, 3 showed the altered leaf structure and the others were normal. The feature of this mutant was the deep serration of leaflet margins. The mutant had large thick leaflets with prominent venation. The mutant bred true in the M 3 and successive generation. Details of the morphological characteristics of the mutant are presented. The mutant exhibited slower growth particularly during the early stages of development, flowered later and attained shorter height. There was an increase in the number of pods, in seed weight and in seed protein content, but number of seed per pod was considerably reduced. The seed coat colour showed a change from green to yellowish green. In the mutant's flowers the stamina were placed much below the stigma level and the stigma sometimes protruded the corolla. Outcrossing of 4% recorded in some of the mutant lines revealed a reduced cleistogamy. The low number of seeds per pod in the mutant could be due to reduced pollen fertility. The mutant behaved as monogenic recessive. The symbols SL/sl are proposed for this allelic pair. The mutant may have use as a green manure crop because of its large foliage and for the breeders as a genetic marker

  17. Characterization of a Weak Allele of Zebrafish cloche Mutant

    Science.gov (United States)

    Ma, Ning; Huang, Zhibin; Chen, Xiaohui; He, Fei; Wang, Kun; Liu, Wei; Zhao, Linfeng; Xu, Xiangmin; Liao, Wangjun; Ruan, Hua; Luo, Shenqiu; Zhang, Wenqing

    2011-01-01

    Hematopoiesis is a complicated and dynamic process about which the molecular mechanisms remain poorly understood. Danio rerio (zebrafish) is an excellent vertebrate system for studying hematopoiesis and developmental mechanisms. In the previous study, we isolated and identified a cloche 172 (clo 172) mutant, a novel allele compared to the original cloche (clo) mutant, through using complementation test and initial mapping. Here, according to whole mount in-situ hybridization, we report that the endothelial cells in clo 172 mutant embryos, although initially developed, failed to form the functional vascular system eventually. In addition, further characterization indicates that the clo 172 mutant exhibited weaker defects instead of completely lost in primitive erythroid cells and definitive hematopoietic cells compared with the clo s5 mutant. In contrast, primitive myeloid cells were totally lost in clo 172 mutant. Furthermore, these reappeared definitive myeloid cells were demonstrated to initiate from the remaining hematopoietic stem cells (HSCs) in clo 172 mutant, confirmed by the dramatic decrease of lyc in clo 172 runx1w84x double mutant. Collectively, the clo 172 mutant is a weak allele compared to the clo s5 mutant, therefore providing a model for studying the early development of hematopoietic and vascular system, as well as an opportunity to further understand the function of the cloche gene. PMID:22132109

  18. Homologous Recombination Defective Arabidopsis Mutants Exhibit Enhanced Sensitivity to Abscisic Acid.

    Directory of Open Access Journals (Sweden)

    Sujit Roy

    Full Text Available Abscisic acid (ABA acts as an important plant hormone in regulating various aspects of plant growth and developmental processes particularly under abiotic stress conditions. An increased ABA level in plant cells inhibits DNA replication and cell division, causing plant growth retardation. In this study, we have investigated the effects of ABA on the growth responses of some major loss-of-function mutants of DNA double-stand break (DSB repair genes in Arabidopsis during seed germination and early stages of seedling growth for understanding the role of ABA in the induction of genome instability in plants. A comparative analysis of ABA sensitivity of wild-type Arabidopsis and the knockout mutant lines related to DSB sensors, including atatm, atatr, the non-homologous end joining (NHEJ pathway genes, and mutants related to homologous recombination (HR pathway genes showed relatively enhanced sensitivity of atatr and HR-related mutants to ABA treatment. The expression levels of HR-related genes were increased in wild-type Arabidopsis (Col-0 during seed germination and early stages of seedling growth. Immunoblotting experiments detected phosphorylation of histone H2AX in wild-type (Col-0 and DSB repair gene mutants after ABA treatment, indicating the activation of DNA damage response due to ABA treatment. Analyses of DSB repair kinetics using comet assay under neutral condition have revealed comparatively slower DSB repair activity in HR mutants. Overall, our results have provided comprehensive information on the possible effect of ABA on DNA repair machinery in plants and also indicated potential functional involvement of HR pathway in repairing ABA induced DNA damage in Arabidopsis.

  19. Functional rescue of mutant ABCA1 proteins by sodium 4-phenylbutyrate.

    Science.gov (United States)

    Sorrenson, Brie; Suetani, Rachel J; Williams, Michael J A; Bickley, Vivienne M; George, Peter M; Jones, Gregory T; McCormick, Sally P A

    2013-01-01

    Mutations in the ATP-binding cassette transporter A1 (ABCA1) are a major cause of decreased HDL cholesterol (HDL-C), which infers an increased risk of cardiovascular disease (CVD). Many ABCA1 mutants show impaired localization to the plasma membrane. The aim of this study was to investigate whether the chemical chaperone, sodium 4-phenylbutyrate (4-PBA) could improve cellular localization and function of ABCA1 mutants. Nine different ABCA1 mutants (p.A594T, p.I659V, p.R1068H, p.T1512M, p.Y1767D, p.N1800H, p.R2004K, p.A2028V, p.Q2239N) expressed in HEK293 cells, displaying different degrees of mislocalization to the plasma membrane and discrete impacts on cholesterol efflux, were subject to treatment with 4-PBA. Treatment restored localization to the plasma membrane and increased cholesterol efflux function for the majority of mutants. Treatment with 4-PBA also increased ABCA1 protein expression in all transfected cell lines. In fibroblast cells obtained from low HDL-C subjects expressing two of the ABCA1 mutants (p.R1068H and p.N1800H), 4-PBA increased cholesterol efflux without any increase in ABCA1 expression. Our study is the first to investigate the effect of the chemical chaperone, 4-PBA on ABCA1 and shows that it is capable of restoring plasma membrane localization and enhancing the cholesterol efflux function of mutant ABCA1s both in vitro and ex vivo. These results suggest 4-PBA may warrant further investigation as a potential therapy for increasing cholesterol efflux and HDL-C levels.

  20. ALS mutant SOD1 interacts with G3BP1 and affects stress granule dynamics.

    Science.gov (United States)

    Gal, Jozsef; Kuang, Lisha; Barnett, Kelly R; Zhu, Brian Z; Shissler, Susannah C; Korotkov, Konstantin V; Hayward, Lawrence J; Kasarskis, Edward J; Zhu, Haining

    2016-10-01

    Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. Mutations in Cu/Zn superoxide dismutase (SOD1) are responsible for approximately 20 % of the familial ALS cases. ALS-causing SOD1 mutants display a gain-of-toxicity phenotype, but the nature of this toxicity is still not fully understood. The Ras GTPase-activating protein-binding protein G3BP1 plays a critical role in stress granule dynamics. Alterations in the dynamics of stress granules have been reported in several other forms of ALS unrelated to SOD1. To our surprise, the mutant G93A SOD1 transgenic mice exhibited pathological cytoplasmic inclusions that co-localized with G3BP1-positive granules in spinal cord motor neurons. The co-localization was also observed in fibroblast cells derived from familial ALS patient carrying SOD1 mutation L144F. Mutant SOD1, unlike wild-type SOD1, interacted with G3BP1 in an RNA-independent manner. Moreover, the interaction is specific for G3BP1 since mutant SOD1 showed little interaction with four other RNA-binding proteins implicated in ALS. The RNA-binding RRM domain of G3BP1 and two particular phenylalanine residues (F380 and F382) are critical for this interaction. Mutant SOD1 delayed the formation of G3BP1- and TIA1-positive stress granules in response to hyperosmolar shock and arsenite treatment in N2A cells. In summary, the aberrant mutant SOD1-G3BP1 interaction affects stress granule dynamics, suggesting a potential link between pathogenic SOD1 mutations and RNA metabolism alterations in ALS.

  1. Mitochondrial Calcium Dysregulation Contributes to Dendrite Degeneration Mediated by PD/LBD-Associated LRRK2 Mutants.

    Science.gov (United States)

    Verma, Manish; Callio, Jason; Otero, P Anthony; Sekler, Israel; Wills, Zachary P; Chu, Charleen T

    2017-11-15

    Mutations in leucine-rich repeat kinase 2 (LRRK2) contribute to development of late-onset familial Parkinson's disease (PD), with clinical features of motor and cognitive dysfunction indistinguishable from sporadic PD. Calcium dysregulation plays an important role in PD pathogenesis, but the mechanisms of neurodegeneration remain unclear. Recent reports indicate enhanced excitatory neurotransmission in cortical neurons expressing mutant LRRK2, which occurs before the well-characterized phenotype of dendritic shortening. As mitochondria play a major role in the rapid buffering of cytosolic calcium, we hypothesized that altered mitochondrial calcium handling contributes to dendritic retraction elicited by the LRRK2-G2019S and -R1441C mutations. In primary mouse cortical neurons, we observed increased depolarization-induced mitochondrial calcium uptake. We found that expression of mutant LRRK2 elicited transcriptional upregulation of the mitochondrial calcium uniporter (MCU) and the mitochondrial calcium uptake 1 protein (MICU1) with no change in levels of the mitochondrial calcium antiporter NCLX. Elevated MCU and MICU1 were also observed in LRRK2-mutated patient fibroblasts, along with increased mitochondrial calcium uptake, and in postmortem brains of sporadic PD/PDD patients of both sexes. Transcriptional upregulation of MCU and MICU1 was caused by activation of the ERK1/2 (MAPK3/1) pathway. Inhibiting ERK1/2 conferred protection against mutant LRRK2-induced neurite shortening. Pharmacological inhibitors or RNAi knockdown of MCU attenuated mitochondrial calcium uptake and dendritic/neuritic shortening elicited by mutant LRRK2, whereas expression of a constitutively active mutant of NCLX that enhances calcium export from mitochondria was neuroprotective. These data suggest that an increased susceptibility to mitochondrial calcium dysregulation contributes to dendritic injury in mutant LRRK2 pathogenesis. SIGNIFICANCE STATEMENT Cognitive dysfunction and dementia are

  2. Double-strand break repair and genetic recombination in topoisomerase and primase mutants of bacteriophage T4.

    Science.gov (United States)

    Shcherbakov, Victor P; Kudryashova, Elena

    2014-09-01

    The effects of primase and topoisomerase II deficiency on the double-strand break (DSB) repair and genetic recombination in bacteriophage T4 were studied in vivo using focused recombination. Site-specific DSBs were induced by SegC endonuclease in the rIIB gene of one of the parents. The frequency/distance relationship was determined in crosses of the wild-type phage, topoisomerase II mutant amN116 (gene 39), and primase mutant E219 (gene 61). Ordinary two-factor (i×j) and three-factor (i k×j) crosses between point rII mutations were also performed. These data provide information about the frequency and distance distribution of the single-exchange (splice) and double-exchange (patch) events. In two-factor crosses ets1×i, the topoisomerase and primase mutants had similar recombinant frequencies in crosses at ets1-i distances longer than 1000 bp, comprising about 80% of the corresponding wild-type values. They, however, differ remarkably in crosses at shorter distances. In the primase mutant, the recombinant frequencies are similar to those in the wild-type crosses at distances less than 100 bp, being a bit diminished at longer distances. In two-factor crosses ets1×i of the topoisomerase mutant, the recombinant frequencies were reduced ten-fold at the shortest distances. In three-factor crosses a6 ets1×i, where we measure patch-related recombination, the primase mutant was quite proficient across the entire range of distances. The topoisomerase mutant crosses demonstrated virtually complete absence of rII(+) recombinants at distances up to 33 bp, with the frequencies increasing steadily at longer distances. The data were interpreted as follows. The primase mutant is fully recombination-proficient. An obvious difference from the wild-type state is some shortage of EndoVII function leading to prolonged existence of HJs and thus stretched out ds-branch migration. This is also true for the topoisomerase mutant. However, the latter is deficient in the ss

  3. Similarities and differences in vapor explosion criteria

    International Nuclear Information System (INIS)

    Cronenberg, A.W.

    1978-01-01

    An overview of recent ideas pertaining to vapor explosion criteria indicates that in general sense, a consensus of opinion is emerging on the conditions applicable to explosive vaporization. Experimental and theoretical work has lead a number of investigators to the formulation of such conditions which are quite similar in many respects, although the quantitative details of the model formulation of such conditions are somewhat different. All model concepts are consistent in that an initial period of stable film boiling, separating molten fuel from coolant, is considered necessary (at least for large-scale interactions and efficient intermixing), with subsequent breakdown of film boiling due to pressure and/or thermal effects, followed by intimate fuel-coolant contact and a rapid vaporization process which is sufficient to cause shock pressurization. Although differences arise as to the conditions for and the energetics associated with film boiling destabilization and the mode and energetics of fragmentation and intermixing. However, the principal area of difference seems to be the question of what constitutes the requisite condition(s) for rapid vapor production to cause shock pressurization

  4. Disrupted SOX10 function causes spongiform neurodegeneration in gray tremor mice

    Science.gov (United States)

    Anderson, Sarah R.; Lee, Inyoul; Ebeling, Christine; Stephenson, Dennis A.; Schweitzer, Kelsey M.; Baxter, David; Moon, Tara M.; LaPierre, Sarah; Jaques, Benjamin; Silvius, Derek; Wegner, Michael; Hood, Leroy E.; Carlson, George; Gunn, Teresa M.

    2014-01-01

    Mice homozygous for the gray tremor (gt) mutation have a pleiotropic phenotype that includes pigmentation defects, megacolon, whole body tremors, sporadic seizures, hypo- and dysmyelination of the CNS and PNS, vacuolation of the CNS, and early death. Vacuolation similar to that caused by prions was originally reported to be transmissible, but subsequent studies showed the inherited disease was not infectious. The gt mutation mapped to distal mouse chromosome 15, to the same region as Sox10, which encodes a transcription factor with essential roles in neural crest survival and differentiation. As dominant mutations in mouse or human SOX10 cause white spotting and intestinal aganglionosis, we screened the Sox10 coding region for mutations in gt/gt DNA. An adenosine to guanine transversion was identified in exon 2 that changes a highly conserved glutamic acid residue in the SOX10 DNA binding domain to glycine. This mutant allele was not seen in wildtype mice, including the related GT/Le strain, and failed to complement a Sox10 null allele. Gene expression analysis revealed significant down-regulation of genes involved in myelin lipid biosynthesis pathways in gt/gt brains. Knockout mice for some of these genes develop CNS vacuolation and/or myelination defects, suggesting that their down-regulation may contribute to these phenotypes in gt mutants and could underlie the neurological phenotypes associated with Peripheral demyelinating neuropathy-Central dysmyelinating leukodystrophy-Waardenburg syndrome-Hirschsprung (PCWH) disease, caused by mutations in human SOX10. PMID:25399070

  5. The effect of UVB on flavonoid biosynthesis in wild type and mutant petunia and arabidopsis

    International Nuclear Information System (INIS)

    Ryan, K.G.; Swinny, E.E.; Markham, K.R.; Winefield, C.

    2000-01-01

    Full text: Flavonoids may protect plants against damage by UVB radiation. Flavonoid composition and mRNA expression were determined following growth of plants under natural light, and under natural light with low UVB and with enhanced UVB. In wild-type Arabidopsis and Petunia, UVB induced an increase in total levels of flavonols and this was due to an up-regulation of, several genes coding for key enzymes in the phenylpropanoid pathway. In addition, UVB induced a higher rate of production of the di-hydroxylated si flavonol, quercetin glycoside than of the mono-hydroxylated equivalent, of kaempferol glycoside. Thus the ratio of quercetin to kaempferol increased with UVB treatment in wild type plants, and this suggests that the flavonoid r 3'hydroxylase (F3'H) enzyme, which converts dihydrokaempferol to dihydroquercetin, may play a key role in plant protection from UVB. Mutant plants of both species lacking this F3'H gene were grown under similar UV conditions. Leaves of the mutant Arabidopsis plant (tt7) did not contain quercetin, even under the enhanced UVB treatment. Under the low UVB treatment the total amount of flavonol was similar to the wild-type (Ler), but with increasing UVB, total flavonol (i.e. kaempferol) levels were significantly higher than in similarly treated wild type plants. In the Petunia F3'H mutant, low levels of quercetin were found even in the low UVB treatment, which indicates this variety may be producing some quercetin via an alternative pathway. Under UVB radiation, total flavonoids increased to levels significantly higher than in similarly treated wild type plants, and most of this material was kaempferol. These observations suggest that quercetin is the preferred protective flavonol in wild type plants, due perhaps to enhanced antioxidant or free radical scavenging activity. In mutant plants lacking the F3'H enzyme, the response is to produce a larger amount of a less effective photoprotectant

  6. Cp/Heph mutant mice have iron-induced neurodegeneration diminished by deferiprone

    Science.gov (United States)

    Zhao, Liangliang; Hadziahmetovic, Majda; Wang, Chenguang; Xu, Xueying; Song, Ying; Jinnah, H.A.; Wodzinska, Jolanta; Iacovelli, Jared; Wolkow, Natalie; Krajacic, Predrag; Weissberger, Alyssa Cwanger; Connelly, John; Spino, Michael; Lee, Michael K.; Connor, James; Giasson, Benoit; Harris, Z. Leah; Dunaief, Joshua L.

    2016-01-01

    Brain iron accumulates in several neurodegenerative diseases and can cause oxidative damage, but mechanisms of brain iron homeostasis are incompletely understood. Patients with mutations in the cellular iron-exporting ferroxidase ceruloplasmin (Cp) have brain iron accumulation causing neurodegeneration. Here, we assessed the brains of mice with combined mutation of Cp and its homolog hephaestin. Compared to single mutants, brain iron accumulation was accelerated in double mutants in the cerebellum, substantia nigra, and hippocampus. Iron accumulated within glia, while neurons were iron deficient. There was loss of both neurons and glia. Mice developed ataxia and tremor, and most died by 9 months. Treatment with the oral iron chelator deferiprone diminished brain iron levels, protected against neuron loss, and extended lifespan. Ferroxidases play important, partially overlapping roles in brain iron homeostasis by facilitating iron export from glia, making iron available to neurons. PMID:26303407

  7. Mutants of Cercospora kikuchii altered in cercosporin synthesis and pathogenicity

    International Nuclear Information System (INIS)

    Upchurch, R.G.; Walker, D.C.; Rollins, J.A.; Ehrenshaft, M.; Daub, M.E.

    1991-01-01

    The authors have obtained spontaneous and UV-induced stable mutants, altered in the synthesis of cercosporin, of the fungal soybean pathogen Cercospora kikuchii. The mutants were isolated on the basis of colony color on minimal medium. The UV-induced mutants accumulated, at most, 2% of wild-type cercosporin levels on all media tested. In contrast, cercosporin accumulation by the spontaneous mutants was strongly medium regulated, occurring only on potato dextrose medium but at concentrations comparable to those produced by the wild-type strain. UV-induced mutants unable to synthesize cercosporin on any medium were unable to incite lesions when inoculated onto the soybean host. Cercosporin was reproducibly isolated from all inoculated leaves showing lesions. Although cercosporin involvement in disease has been indirectly suggested by many previous studies, this is the first report in which mutants blocked in cercosporin synthesis have been used to demonstrate that cercosporin is a crucial pathogenicity factor for this fungal genus

  8. Temperature sensitive riboflavin mutants of Penicillium vermiculatum Dangeard

    International Nuclear Information System (INIS)

    Mitra, J.; Chaudhari, K.L.

    1974-01-01

    Two temperature sensitive UV induced riboflavin mutants rib 1 and rib 6 have been physiologically and genetically characterized. The two mutants behave differently with regard to their temperature sensitivity. The rib 1 mutant exhibits a leaky growth in minimal medium between 15 0 C and 30 0 C but grows well when the medium is supplemented with riboflavin. At 35 0 C the growth response of the mutant is at its max. and at 40 0 C and below 15 0 C it ceases to grow. The rib 6 mutant which is red brown in colour shows wild type character at temp. below 25 0 C in minimal medium but requires riboflavin at 30 0 C and above. Heterokaryotic analysis revealed the nonallelic nature of the two temperature mutants. Genetic tests of allelic relationship between riboflavin markers by crossing were also done. (author)

  9. Highly productive mutant genotypes in barley - direct use in practice and in successive recombination

    International Nuclear Information System (INIS)

    Gustafsson, Aa.; Lundqvist, U.

    1984-01-01

    Three special cases of induced mutations in barley are discussed in this paper. They are denoted here as the Gunilla, the Pallas and the Mari cases, after the three named varieties to which the original mutants gave rise. The original mutants described represent just a small sample of the induced mutants, many of which have been tested in practice and have been further studied in basic genetics and evolutionary research. The three approved varieties have given rise to further recombination families, which also to some extent have been fused. Two of the mutant cases - Pallas and Mari - were directly useful in practice and officially approved. The third case involved a mutant of special appearance - a ''bushy type'' with an intense blue wax coating and with a supreme lodging resistance. The mutant was used in developing the Gunilla variety, which arose by recombination breeding. This variety has been highly satisfactory in further gene recombination work. A similar situation has prevailed with regard to the Pallas and Mari families arising after gene recombination, too. Up to now, the Gunilla, Pallas and Mari families include a long series of released and officially approved varieties. Several of them represent valuable agricultural contributions with wide areas of cultivation. These three mutants - with their recombination families - led to greatly increased straw stiffness and high grain production. Their phenotypic expression often corresponds to a dwarf or semidwarf description. One of the mutants - the Mari genotype - represents a group of genes and alleles which give rise to profound changes in the photoperiod (and partially also in the thermoperiod) behaviour. In fact, often even such small changes have a fundamental influence on adaptation and distribution. Data are presented analysing the property of lodging resistance with the background of plant, tiller and internode structure. A method of partial back-mutation was worked out in separating traits generally

  10. The levels of mutant K-RAS and mutant N-RAS are rapidly reduced in a Beclin1 / ATG5 -dependent fashion by the irreversible ERBB1/2/4 inhibitor neratinib.

    Science.gov (United States)

    Booth, Laurence; Roberts, Jane L; Poklepovic, Andrew; Kirkwood, John; Sander, Cindy; Avogadri-Connors, Francesca; Cutler, Richard E; Lalani, Alshad S; Dent, Paul

    2018-02-01

    The FDA approved irreversible inhibitor of ERBB1/2/4, neratinib, was recently shown to rapidly down-regulate the expression of ERBB1/2/4 as well as the levels of c-MET and mutant K-RAS via autophagic degradation. In the present studies, in a dose-dependent fashion, neratinib reduced the expression levels of mutant K-RAS or of mutant N-RAS, which was augmented in an additive to greater than additive fashion by the HDAC inhibitors sodium valproate and AR42. Neratinib could reduce PDGFRα levels in GBM cells, that was enhanced by sodium valproate. Knock down of Beclin1 or of ATG5 prevented neratinib and neratinib combined with sodium valproate / AR42 from reducing the expression of mutant N-RAS in established PDX and fresh PDX models of ovarian cancer and melanoma, respectively. Neratinib and the drug combinations caused the co-localization of mutant RAS proteins and ERBB2 with Beclin1 and cathepsin B. The drug combination activated the AMP-dependent protein kinase that was causal in enhancing HMG Co A reductase phosphorylation. Collectively, our data reinforce the concept that the irreversible ERBB1/2/4 inhibitor neratinib has the potential for use in the treatment of tumors expressing mutant RAS proteins.

  11. Some mutants in maize obtained by irradiation with thermal neutrons

    International Nuclear Information System (INIS)

    Diaconu, P.

    1993-01-01

    Irradiation was carried out at the Bucharest Institute of Atomic Physics and the National Laboratory Brookhaven, USA. A description is given of 22 genic mutants affecting leaf color, plant size, and branching capacity. Characteristics related to pollen fertility and the vegetative period were affected in all the mutants. Improvement of pollen fertility was attempted over four generations without success. The maize mutants obtained by irradiation may be considered as being without practical significance. (author). 7 figs., 1 tab. 11 ref

  12. Chemotaxis-defective mutants of the nematode Caenorhabditis elegans.

    Science.gov (United States)

    Dusenbery, D B; Sheridan, R E; Russell, R L

    1975-06-01

    The technique of countercurrent separation has been used to isolate 17 independent chemotaxis-defective mutants of the nematode Caenorhabditis elegans. The mutants, selected to be relatively insensitive to the normally attractive salt NaCl, show varying degrees of residual sensitivity; some are actually weakly repelled by NaCl. The mutants are due to single gene defects, are autosomal and recessive, and identify at least five complementation groups.

  13. Study on ionizing radiosensitivity of respiratory deficiency yeast mutants

    International Nuclear Information System (INIS)

    Mao Shuhong; Chinese Academy of Sciences, Beijing; Jin Genming; Wei Zengquan; Xie Hongmei

    2006-01-01

    The radiosensitivity of respiratory deficiency yeast mutants has been studied in this work. The mutants which were screened from the yeasts after ionizing irradiation were irradiated with 12 C 6+ at different doses. Because of the great change in its mitochondria and mitochondrial DNA, the respiratory deficiency yeast mutants show radio-sensitivity at dose less than 1 Gy and radioresistance at doses higher than 1 Gy. (authors)

  14. Defective Glycinergic Synaptic Transmission in Zebrafish Motility Mutants

    OpenAIRE

    Hirata, Hiromi; Carta, Eloisa; Yamanaka, Iori; Harvey, Robert J.; Kuwada, John Y.

    2010-01-01

    Glycine is a major inhibitory neurotransmitter in the spinal cord and brainstem. Recently, in vivo analysis of glycinergic synaptic transmission has been pursued in zebrafish using molecular genetics. An ENU mutagenesis screen identified two behavioral mutants that are defective in glycinergic synaptic transmission. Zebrafish bandoneon (beo) mutants have a defect in glrbb, one of the duplicated glycine receptor (GlyR) β subunit genes. These mutants exhibit a loss of glycinergic synaptic ...

  15. Studies on mutant breeding of Hibiscus syriacus

    International Nuclear Information System (INIS)

    Song, Hi Sup; Kim, Jin Kyu; Lee, Ki Un; Kim, Young Taik.

    1997-01-01

    Hibiscus has been known as a national flower of Korea. Hibiscus has such a characteristic of self-incompatibility that all the plant exist as natural hybrids and have heterogeneous genes. Many domestic 91 varieties of Hibiscus syriacus were collected. Radiosensitivity of H. Syriacus irradiated with γ-ray was investigated in plant cuttings. The plant height was reduced by 45% in 5KR irradiated group, compared to control group. The radiation dose of 5KR could be recommended for mutation breeding of Hibiscus cuttings. Radiosensitivity of γ-ray irradiated Hibiscus seed were investigated. The germination rate, survival rate and plant height was better in the 4KR irradiation plot than control. The radiation dose of 10∼12KR are recommended for mutation breeding of Hibiscus. Promising mutant lines were selected form the varieties of Hwarang, Wolsan no. 176, Ilpyondansim, Emille, Hanol, Yongkwang, Saeyongkwang, Chungmu, Imjinhong, Arang, Hungdansim-1 and Hongdansim-2. (author). 66 refs., 16 tabs., 13 figs

  16. Google: a narrativa de uma marca mutante

    Directory of Open Access Journals (Sweden)

    Elizete de Azevedo Kreutz

    2010-01-01

    Full Text Available As marcas mutantes já fazem parte de nossa realidade, embora ainda não totalmente percebidas e/ou aceitas como tal. O presente artigo busca refletir sobre a relevância dessas novas estratégias de comunicação e branding, identificando suas principais características. Para isso, utilizamos o método de estudo de caso, o Google, ancorado nos métodos de pesquisa bibliográfica e de internet. A escolha foi intencional, posto que a organização é referência em sua categoria, mecanismo de busca, e reflete essa estratégia comunicacional contemporânea. Como resultado, as informações obtidas nos possibilitam compreender essa tendência de comportamento de marca que busca a interação com seus públicos.

  17. Studies on mutant breeding of Hibiscus syriacus

    Energy Technology Data Exchange (ETDEWEB)

    Song, Hi Sup; Kim, Jin Kyu; Lee, Ki Un; Kim, Young Taik

    1997-01-01

    Hibiscus has been known as a national flower of Korea. Hibiscus has such a characteristic of self-incompatibility that all the plant exist as natural hybrids and have heterogeneous genes. Many domestic 91 varieties of Hibiscus syriacus were collected. Radiosensitivity of H. Syriacus irradiated with {gamma}-ray was investigated in plant cuttings. The plant height was reduced by 45% in 5KR irradiated group, compared to control group. The radiation dose of 5KR could be recommended for mutation breeding of Hibiscus cuttings. Radiosensitivity of {gamma}-ray irradiated Hibiscus seed were investigated. The germination rate, survival rate and plant height was better in the 4KR irradiation plot than control. The radiation dose of 10{approx}12KR are recommended for mutation breeding of Hibiscus. Promising mutant lines were selected form the varieties of Hwarang, Wolsan no. 176, Ilpyondansim, Emille, Hanol, Yongkwang, Saeyongkwang, Chungmu, Imjinhong, Arang, Hungdansim-1 and Hongdansim-2. (author). 66 refs., 16 tabs., 13 figs.

  18. Development of similarity theory for control systems

    Science.gov (United States)

    Myshlyaev, L. P.; Evtushenko, V. F.; Ivushkin, K. A.; Makarov, G. V.

    2018-05-01

    The area of effective application of the traditional similarity theory and the need necessity of its development for systems are discussed. The main statements underlying the similarity theory of control systems are given. The conditions for the similarity of control systems and the need for similarity control control are formulated. Methods and algorithms for estimating and similarity control of control systems and the results of research of control systems based on their similarity are presented. The similarity control of systems includes the current evaluation of the degree of similarity of control systems and the development of actions controlling similarity, and the corresponding targeted change in the state of any element of control systems.

  19. Recombination-deficient mutants of Bacillus subtilis

    International Nuclear Information System (INIS)

    Sadaie, Y.; Kada, T.

    1976-01-01

    Two mutant strains of Bacillus subtilis Marburg, NIG43 and NIG45, were isolated. They showed high sensitivities to gamma rays, ultraviolet light (uv), and chemicals. Deficiencies in genetic recombination of these two mutants were shown by the experiments on their capacity in transformation, SPO2 transfection, and PBS1 phage transduction, as well as on their radiation and drug sensitivities and their Hcr + capacity for uv-exposed phage M2. Some of these characteristics were compared with those of the known strains possessing the recA1 or recB2 alleles. Mapping studies revealed that the mutation rec-43 of strain NIG43 lies in the region of chromosome replication origin. The order was purA dna-8132 rec-43. Another mutation, rec-45, of strain NIG45 was found to be tightly linked to recA1. The mutation rec-43 reduced mainly the frequency of PBS1 transduction. On the other hand, the mutation rec-45 reduced the frequency of recombination involved both in transformation and PBS1 tranduction. The mutation rec-43 of strain NIG43 is conditional, but rec-45 of strain NIG45 is not. The uv impairment in cellular survival of strain NIG43 was gradually reverted at higher salt or sucrose concentrations, suggesting cellular possession of a mutated gene product whose function is conditional. In contrast to several other recombination-deficient strains, SPO2 lysogens of strains NIG43 and NIG45 were not inducible, indicating involvement of rec-43 + or rec-45 + gene product in the development of SPO2 prophage to a vegetative form. The uv-induced deoxyribonucleic acid degradation in vegetative cells was higher in rec-43 and rec-45 strains

  20. Winter barley mutants created in the Ukraine

    International Nuclear Information System (INIS)

    Zayats, O.M.

    2001-01-01

    Full text: Increasing fodder and protein production is one of the objectives of the development of agriculture in Ukraine. Higher productivity of fodder crops, due to new highly productive varieties, is the means to meet this aim. Winter barley is an important crop for fodder purposes. The climate of the Ukraine is favourable for growing this crop. The areas used for the growth of winter barley are however, small (500,000-550,000 ha) and there is a shortage of good quality varieties. The main aim of the work was therefore to create new varieties of highly productive winter barley, of good quality. The new varieties and mutation lines of winter barley were created under the influence of water solutions of N-nitroso-N-methylurea (NMH - 0,012, 0,005%), N-nitroso-N-ethylurea (NEH - 0,05; 0.025; 0,012%) ethyleneimine (EI - 0,02; 0,01; 0,005%) on winter barley seeds of the varieties of local and foreign selections. On the basis of many years of investigations (1984-94) the following mutations were described: hard-grained, winter-hardiness, earliness, middle-maturity, late-maturity, wide and large leaves, narrow leaves, multinodal, great number of leaves, great number of flowers, strong stem (lodging resistant), tallness, semi-dwarfness, dwarfness, and high productivity. Particularly valuable are mutants with high productivity of green bulk. Their potential yield is 70 t/ha. As a result of the work two varieties of winter barley 'Shyrokolysty' and 'Kormovy' were released into the State register of plant varieties of the Ukraine. The other valuable mutant genotypes are used in cross breeding programmes. (author)

  1. Multilocation trial of potential selected mutant lines of groundnut (arachis hypogaea) at 3 location in Peninsular Malaysia

    International Nuclear Information System (INIS)

    Abdul Rahim Harun; Rusli Ibrahim; Khairuddin Abdul Rahim; Shuhaimi Shamsuddin

    2002-01-01

    Two fixed mutant lines of groundnut derived from cultivar Matjan were selected for their yield potential at M 1 0 generation. Multilocation trial of these mutants (MJ40/42 and MJ20/165-5) was carried out to evaluate genotype stability at different climate and soil types in Peninsular Malaysia. The mutant lines were planted and compared with their parent (Matjan) and control variety (MKT1). The identified locations were in Taiping (Perak), Machang (Kelantan), and Air Hitam (Johor). The soils at the locations were of the Serdang, Bungor and Rengam series, respectively. The trial was carried out simultaneously in the same year at each location. Mutant MJ20/165-5 showed stable performance at all location compared to other genotypes tested. Its yield was higher than the parent in Kelantan and Johor trial and showed similar performance in Perak. This mutant also showed better yield performance than the control varieties in the Kelantan trial. Meanwhile, mutant line MJ40/42 gave better yield in Kelantan and Johor but did not perform well in Perak as compared to its parent and control varieties. (Author)

  2. Properties of adenyl cyclase and cyclic adenosine 3',5'-monophosphate receptor protein-deficient mutants of Escherichia coli

    International Nuclear Information System (INIS)

    Kumar, S.

    1976-01-01

    Several spontaneous cya and crp mutants of Escherichia coli have been selected as clones simultaneously resistant to phage lambda and nalidixic acid and characterized. Both cya and crp mutants have been found to grow as cocci with increased doubling times. They have increased resistance to some mutagens (methylmethanesulfonate, ultraviolet light, gamma rays), antibiotics (nalidixic acid, ampicillin), phages (lambda, T6), sublethal heat and hypotonic shock, and decreased resistance to neutral detergents (sodium dodecyl sulfate, sodium deoxycholate), a protein synthesis inhibitor (streptomycin), and a respiratory inhibitor (sodium azide). The nature of changes in cell parameters indicate fundamental alterations in the envelope structure of the cya and crp mutant cells. The new cya and crp mutants have been found to be multiply carbohydrate negative and nonmotile in conformity with similar previously isolated mutants. Studies of revertants and phi 80 cya + and phi 80 cya transductants indicated that the pleiotropic phenotype is related to a single mutational event at the cya or the crp locus in the mutants

  3. Characterization of D-myo-inositol 3-phosphate synthase gene expression in two soybean low phytate mutants

    International Nuclear Information System (INIS)

    Yuan Fengjie; Dong Dekun; Li Baiquan; Yu Xiaomin; Fu Xujun; Zhu Danhua; Zhu Shenlong; Yang Qinghua

    2013-01-01

    1D-myo-inositol 3-phosphate synthase (MIPS) gene plays a significant role in phytic acid biosynthesis. In this study, we used two low phytic acid mutants Gm-lpa-TW-1, Gm-lpa-ZC-2 and their respective wild type parents Taiwan75 and Zhechun No.3 to analyze the expression pattern and characterization of MIPS1 gene. The results showed that there was a common expression pattern of MIPS1 in soybean developing seeds. Expression was weak as detected by RT-PCR in initial stage, increased in the following stages, and the peak expression was appeared in 22 day after flowering (DAF). The expression of MIPS1 gene of non-seed tissues in mutant Gm-lpa-TW-1 and its wildtype Taiwan75 was very weak. In the developing seeds, the MIPS1 expression by qRT-PCR revealed a significant reduction in 22 DAF in mutant Gm-lpa-TW-1 as compared with the wildtype. Similarly, the expression of MIPS1 gene in non-seed tissue of Zhenchun No.3 and Gm-lpa-ZC-2 was very weak. However, stronger expression in developing seeds of the mutant Gm-lpa-ZC-2 than Zhechun No.3 was found. We concluded that the MIPS1 gene expression in the developing seed exhibited an up-regulation pattern in mutant Gm-lpa-ZC-2, but a down-regulation pattern in the mutant Gm-lpa-TW-1. (authors)

  4. Oxidized/misfolded superoxide dismutase-1: the cause of all amyotrophic lateral sclerosis?

    Science.gov (United States)

    Kabashi, Edor; Valdmanis, Paul N; Dion, Patrick; Rouleau, Guy A

    2007-12-01

    The identification in 1993 of superoxide dismutase-1 (SOD1) mutations as the cause of 10 to 20% of familial amyotrophic lateral sclerosis cases, which represents 1 to 2% of all amyotrophic lateral sclerosis (ALS) cases, prompted a substantial amount of research into the mechanisms of SOD1-mediated toxicity. Recent experiments have demonstrated that oxidation of wild-type SOD1 leads to its misfolding, causing it to gain many of the same toxic properties as mutant SOD1. In vitro studies of oxidized/misfolded SOD1 and in vivo studies of misfolded SOD1 have indicated that these protein species are selectively toxic to motor neurons, suggesting that oxidized/misfolded SOD1 could lead to ALS even in individuals who do not carry an SOD1 mutation. It has also been reported that glial cells secrete oxidized/misfolded mutant SOD1 to the extracellular environment, where it can trigger the selective death of motor neurons, offering a possible explanation for the noncell autonomous nature of mutant SOD1 toxicity and the rapid progression of disease once the first symptoms develop. Therefore, considering that sporadic (SALS) and familial ALS (FALS) cases are clinically indistinguishable, the toxic properties of mutated SOD1 are similar to that of oxidized/misfolded wild-type SOD1 (wtSOD1), and secreted/extracellular misfolded SOD1 is selectively toxic to motor neurons, we propose that oxidized/misfolded SOD1 is the cause of most forms of classic ALS and should be a prime target for the design of ALS treatments.

  5. Isoenzymes performance of some rice varieties and their mutants

    International Nuclear Information System (INIS)

    Winarno, Ermin; Suliwarno, Ambyah; Ismachin, M.

    1992-01-01

    Isoenzymes performance of some rice varieties and their mutants. Genetics studies on alcohol dehydrogenase, malic enzyme, peroxidase, acid phosphase, and aminopeptidase isoenzymes were carried out on several groups of rice varieties and their mutant lines. The first groups consisted of Atomita I, Pelita I/1, A227/5, Mudgo, TN-1, and IR-26. The second group was Cisadane variety and its five mutants, namely OBS 18, OBS 208, OBS 297, OBS 306, and OBS 330. The third group was mutants line 627-10-3 and its mutants, namely 1063, 1066, 1067, 1076, and 1090. Isoenzymes extracts of the rice leaves were fractionated using polyacrylamide gel disc electrophoresis. The pattern of acid phosphate isoenzyme shows the specific character of rice mutants susceptible to brown plant hopper biotype 1. The gene(s) controlling malic enzyme in Cisadane's mutants is (are) estimated more resistant toward gamma irradiation than gene(s) responsible for controlling the other enzymes. Generally, the isoenzymes zymograms show that gene(s) controlling the mutants enzyme have undergone mutation. This case is shown by the changes of Rm value, as well as the amount and intensity of mutants bands. (authors). 7 refs., 7 figs

  6. Agronomic performance of old soybean variety 'Altona' derived mutants

    International Nuclear Information System (INIS)

    Hodosne, K.G.; Heszky, L.E.

    2001-01-01

    An induced mutation program has been initiated at the Department of Genetics and Plant Breeding to develop early maturing cultivars with good yielding capacity. Some new mutants have been produced by irradiation of variety Altona with 60 Co gamma rays. Ten years of breeding resulted in two new mutant varieties named 'Noventa' and 'Gate 511'. The present study deals with agronomic performance of these mutants. Registered soybean varieties Altona and 'McCall' as well as Altona derived mutants (Gate 511 and Noventa) have been compared

  7. Morphological and physiological investigations on mutants of Fusarium monoliforme IM

    International Nuclear Information System (INIS)

    Gancheva, V.

    1996-01-01

    High-producing mutants of Fusarium moniliforme IM are obtained as a result of gamma irradiation. The cultural characteristics of mutant strains 3284, 3211 and 76 following incubation of the producers for 14 days on potato-glucose agar are described. The colour of the aerial and substrate mycelium and the ability of the mutant strains to form conidiae and pigments are discussed in detail. The differences in the ability of mutants to assimilate different carbon and nitrogen sources are of specific importance for modelling nutrient media for submerged cultivation of F. moniliforme. 2 tabs., 2 figs. 7 refs

  8. New applications of CRISPR/Cas9 system on mutant DNA detection.

    Science.gov (United States)

    Jia, Chenqiang; Huai, Cong; Ding, Jiaqi; Hu, Lingna; Su, Bo; Chen, Hongyan; Lu, Daru

    2018-01-30

    The detection of mutant DNA is critical for precision medicine, but low-frequency DNA mutation is very hard to be determined. CRISPR/Cas9 is a robust tool for in vivo gene editing, and shows the potential for precise in vitro DNA cleavage. Here we developed a DNA mutation detection system based on CRISPR/Cas9 that can detect gene mutation efficiently even in a low-frequency condition. The system of CRISPR/Cas9 cleavage in vitro showed a high accuracy similar to traditional T7 endonuclease I (T7E1) assay in estimating mutant DNA proportion in the condition of normal frequency. The technology was further used for low-frequency mutant DNA detection of EGFR and HBB somatic mutations. To the end, Cas9 was employed to cleave the wild-type (WT) DNA and to enrich the mutant DNA. Using amplified fragment length polymorphism analysis (AFLPA) and Sanger sequencing, we assessed the sensitivity of CRISPR/Cas9 cleavage-based PCR, in which mutations at 1%-10% could be enriched and detected. When combined with blocker PCR, its sensitivity reached up to 0.1%. Our results suggested that this new application of CRISPR/Cas9 system is a robust and potential method for heterogeneous specimens in the clinical diagnosis and treatment management. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Genetic diversity analysis in rice mutants using isozyme and Morphological markers

    Energy Technology Data Exchange (ETDEWEB)

    Fuentes, Jorge L; Alvarez, Alba [Centro de Estudios Aplicados al Desarrollo Nuclear, La Habana (Cuba); Deus, Juan E [Instituto de Investigaciones del Arroz. Bauta, La Habana (Cuba); Duque, Miriam C [Centro Internacional de Agricultura Tropical, Cali (Colombia); Cornide, Maria T [Centro Nacional de Investigaciones Cientificas, La Habana (Cuba)

    1999-07-01

    In this work, isozyme and agromorphologic variability of radiation-induced rice mutants with different cytoplasm base was surveyed. Agromorphologic data (plant type, lodging resistance, life cycle and yielding) were transformed into binary data. This markers, along with isozyme (Peroxidases, Esterases, Catalases, Alcohol Dehydrogenases and Polyphenoloxidase) data, were considered for genetic diversity analyses in order to estimate the extent of diversity generated by ionizing radiation. Genetic Similarity between individuals was obtained based on Dice's Coefficient. The UPGMA phenogram defined three main clusters that clearly corresponded to the different cytoplasm sources. However, further discrimination between control varieties and their mutants could be obtained. Bootstrapping analysis was performed to estimate the robustness of the group in the phenogram. According to their bootstrap P value (99.6%), Basmati-370 mutant lines could be considered statistically different from their control. This analysis is suggested as an useful supporting tool for an accurate varietal validation. A Multiple Correspondence Analysis (MCA) showed individuals dispersion around the three principal axis of variation. In general the UPGMA phenogram pattern was corroborated at MCA. Variables such as life cycle, presence of bands Est-a and Prx-m and the absence of Est-i, Prx-h and Prx-i accounted for the higher contribution to variation. The adequacy of morphological and isozyme descriptors for new mutant lines validation is also discussed.

  10. Genetic diversity analysis in rice mutants using isozyme and Morphological markers

    International Nuclear Information System (INIS)

    Fuentes, Jorge L.; Alvarez, Alba; Deus, Juan E.; Duque, Miriam C.; Cornide, Maria T.

    1999-01-01

    In this work, isozyme and agromorphologic variability of radiation-induced rice mutants with different cytoplasm base was surveyed. Agromorphologic data (plant type, lodging resistance, life cycle and yielding) were transformed into binary data. This markers, along with isozyme (Peroxidases, Esterases, Catalases, Alcohol Dehydrogenases and Polyphenoloxidase) data, were considered for genetic diversity analyses in order to estimate the extent of diversity generated by ionizing radiation. Genetic Similarity between individuals was obtained based on Dice's Coefficient. The UPGMA phenogram defined three main clusters that clearly corresponded to the different cytoplasm sources. However, further discrimination between control varieties and their mutants could be obtained. Bootstrapping analysis was performed to estimate the robustness of the group in the phenogram. According to their bootstrap P value (99.6%), Basmati-370 mutant lines could be considered statistically different from their control. This analysis is suggested as an useful supporting tool for an accurate varietal validation. A Multiple Correspondence Analysis (MCA) showed individuals dispersion around the three principal axis of variation. In general the UPGMA phenogram pattern was corroborated at MCA. Variables such as life cycle, presence of bands Est-a and Prx-m and the absence of Est-i, Prx-h and Prx-i accounted for the higher contribution to variation. The adequacy of morphological and isozyme descriptors for new mutant lines validation is also discussed

  11. Mutation Breeding and Selection for Phenotypic Mutants in Standard Rice Varieties by Ion Beam

    International Nuclear Information System (INIS)

    Puddhanon, Prawit; Pintanon, Prateep; Chaithep, Waree; Songjuntuke, Ksan

    2009-07-01

    Full text: Effects of 80 keV ion beam (10 16 ion/cm 2 on mutations of RD6 and Sanpatong 1 rice varieties were studied in 2006. In order to obtain the phenotypic mutants, each variety was sown in the laboratory and under field conditions at Maejo University in 2007 dry season. Seed germination noticeably declined. For RD6, only 45.1% germinated in the laboratory, and 18.1% were established under the field condition. Similarly, 62.3% of Sanpatong 1 germinated in the laboratory and 31.4% established in the field. No phenotypic mutants were observed in the first generation (M 1 ). The M2 seeds were harvested separately from 3 panicles of each M plant in RD6 and Sanpatong1, totaling 810 and 1,878 lines, respectively. In 2007 rainy season, they were planted on a panicle to row basis. It was found that more phenotypic mutants were observed in the M 2 for Sanpatong 1 than for RD6. The mutant characters included dwarf plants, early maturity, male sterility and larger panicle sizes. As a result, about 420 within line selections were collected and the M 3 seeds were harvested for further field condition and gene markers evaluations

  12. Engaging narratives evoke similar neural activity and lead to similar time perception.

    Science.gov (United States)

    Cohen, Samantha S; Henin, Simon; Parra, Lucas C

    2017-07-04

    It is said that we lose track of time - that "time flies" - when we are engrossed in a story. How does engagement with the story cause this distorted perception of time, and what are its neural correlates? People commit both time and attentional resources to an engaging stimulus. For narrative videos, attentional engagement can be represented as the level of similarity between the electroencephalographic responses of different viewers. Here we show that this measure of neural engagement predicted the duration of time that viewers were willing to commit to narrative videos. Contrary to popular wisdom, engagement did not distort the average perception of time duration. Rather, more similar brain responses resulted in a more uniform perception of time across viewers. These findings suggest that by capturing the attention of an audience, narrative videos bring both neural processing and the subjective perception of time into synchrony.

  13. Phenotype of transgenic mice carrying a very low copy number of the mutant human G93A superoxide dismutase-1 gene associated with amyotrophic lateral sclerosis.

    Directory of Open Access Journals (Sweden)

    Jeffrey S Deitch

    Full Text Available Amyotrophic lateral sclerosis (ALS is a progressive neurodegenerative disease of the motor neuron. While most cases of ALS are sporadic, 10% are familial (FALS with 20% of FALS caused by a mutation in the gene that codes for the enzyme Cu/Zn superoxide dismutase (SOD1. There is variability in sporadic ALS as well as FALS where even within the same family some siblings with the same mutation do not manifest disease. A transgenic (Tg mouse model of FALS containing 25 copies of the mutant human SOD1 gene demonstrates motor neuron pathology and progressive weakness similar to ALS patients, leading to death at approximately 130 days. The onset of symptoms and survival of these transgenic mice are directly related to the number of copies of the mutant gene. We report the phenotype of a very low expressing (VLE G93A SOD1 Tg carrying only 4 copies of the mutant G93ASOD1 gene. While weakness can start at 9 months, only 74% of mice 18 months or older demonstrate disease. The VLE mice show decreased motor neurons compared to wild-type mice as well as increased cytoplasmic translocation of TDP-43. In contrast to the standard G93A SOD1 Tg mouse which always develops motor weakness leading to death, not all VLE animals manifested clinical disease or shortened life span. In fact, approximately 20% of mice older than 24 months had no motor symptoms and only 18% of VLE mice older than 22 months reached end stage. Given the variable penetrance of clinical phenotype, prolonged survival, and protracted loss of motor neurons the VLE mouse provides a new tool that closely mimics human ALS. This tool will allow the study of pathologic events over time as well as the study of genetic and environmental modifiers that may not be causative, but can exacerbate or accelerate motor neuron disease.

  14. Allele-specific Gene Silencing of Mutant mRNA Restores Cellular Function in Ullrich Congenital Muscular Dystrophy Fibroblasts

    Directory of Open Access Journals (Sweden)

    Satoru Noguchi

    2014-01-01

    Full Text Available Ullrich congenital muscular dystrophy (UCMD is an inherited muscle disorder characterized clinically by muscle weakness, distal joint hyperlaxity, and proximal joint contractures. Sporadic and recessive mutations in the three collagen VI genes, COL6A1, COL6A2, and COL6A3, are reported to be causative. In the sporadic forms, a heterozygous point mutation causing glycine substitution in the triple helical domain has been identified in higher rate. In this study, we examined the efficacy of siRNAs, which target point mutation site, on specific knockdown toward transcripts from mutant allele and evaluated consequent cellular phenotype of UCMD fibroblasts. We evaluated the effect of siRNAs targeted to silence-specific COL6A1 alleles in UCMD fibroblasts, where simultaneous expression of both wild-type and mutant collagen VI resulted in defective collagen localization. Addition of mutant-specific siRNAs allowed normal extracellular localization of collagen VI surrounding fibroblasts, suggesting selective inhibition of mutant collagen VI. Targeting the single-nucleotide COL6A1 c.850G>A (p.G284R mutation responsible a sporadic autosomal dominant form of UCMD can potently and selectively block expression of mutant collagen VI. These results suggest that allele-specific knockdown of the mutant mRNA can potentially be considered as a therapeutic procedure in UCMD due to COL6A1 point mutations.

  15. Selection of mutants resistant to black spot disease by chronic irradiation of gamma-rays in Japanese pear 'Osanijisseiki'

    International Nuclear Information System (INIS)

    Masuda, Tetsuo; Yoshioka, Toji; Kotobuki, Kazuo; Sanada, Tetsuro; Inoue, Kosuke; Murata, Kenji; Kitagawa, Kenichi; Tabira, Hiroki; Yoshida, Akira

    1997-01-01

    'Osanijisseiki', a self-compatible, spontaneous bud sport of the Japanese pear 'Nijisseiki' is an excellent cultivar with a smooth skin. However, this cultivar is susceptible to Japanese pear black spot disease caused by Alternaria alternata Japanese pear pathotype. To obtain resistant mutants from 'Osanijisseiki', nursery plants of 'Osanijisseiki' have been irradiated chronically with gamma-rays in the Gamma Field of the Institute of Radiation Breeding, NAR, MAFF, since 1986. Screening tests using AK toxin, a host-specific toxin produced by A. alternata Japanese pear pathotype, were performed form 1988 to 1993. Four branches of young trees planted at a distance of 40 m from the 60 Co source were selected as being resistant mutants in 1991 (IRB 502-13T and IRB 502-14T) and 1993 (IRB 502-17T and IRB 502-18T). Sensitivity of the four resistant mutants to AK-toxin and susceptibility to the pathogen were compared with other of susceptible and resistant cultivars. The results showed that these four mutants possessed intermediate resistance. Furthermore, a mutant, IRB 502-13T, had the same characteristics as the original 'Osanijisseiki', except for the difference in toxin sensitivity. The characteristics of the other mutants, IRB 502 14-T, IRB 502-17T, and IRB 502-18T, care being examined. (author)

  16. New early-ripening wheat mutant lines from the varieties Norman and Avalon

    International Nuclear Information System (INIS)

    Djelepov, K.

    1988-01-01

    The English wheat varieties Norman and Avalon are high-productive, resistant to lodging and to diseases but late-ripening in Bulgaria. They are 10-15 days later than the variety Sadovo 1 and therefore suffer often from dry and hot weather, causing premature ripening and shrivelled seed. Dry seeds from the two varieties were irradiated with 10 and 15 kR 60 Co gamma rays. In M 2 , several earlier ripening forms were selected and they were studied also in M 3 in 1987. In the Table, four early ripening mutant lines and the respective initial varieties are compared. They vary significantly in plant height and grain size. The mutant lines of Norman produce smaller grain but all mutants show a higher hectoliter weight. The mutant lines head and mature 4 to 10 days earlier than the respective initial varieties. Some of them are as productive as the standard and other cultivated varieties. We shall continue testing their productivity and possibilities for their use in the breeding

  17. Development and characterization of mutant winter wheat (Triticum aestivum L.) accessions resistant to the herbicide quizalofop.

    Science.gov (United States)

    Ostlie, Michael; Haley, Scott D; Anderson, Victoria; Shaner, Dale; Manmathan, Harish; Beil, Craig; Westra, Phillip

    2015-02-01

    New herbicide resistance traits in wheat were produced through the use of induced mutagenesis. While herbicide-resistant crops have become common in many agricultural systems, wheat has seen few introductions of herbicide resistance traits. A population of Hatcher winter wheat treated with ethyl methanesulfonate was screened with quizalofop to identify herbicide-resistant plants. Initial testing identified plants that survived multiple quizalofop applications. A series of experiments were designed to characterize this trait. In greenhouse studies the mutants exhibited high levels of quizalofop resistance compared to non-mutant wheat. Sequencing ACC1 revealed a novel missense mutation causing an alanine to valine change at position 2004 (Alopecurus myosuroides reference sequence). Plants carrying single mutations in wheat's three genomes (A, B, D) were identified. Acetyl co-enzyme A carboxylase in resistant plants was 4- to 10-fold more tolerant to quizalofop. Populations of segregating backcross progenies were developed by crossing each of the three individual mutants with wild-type wheat. Experiments conducted with these populations confirmed largely normal segregation, with each mutant allele conferring an additive level of resistance. Further tests showed that the A genome mutation conferred the greatest resistance and the B genome mutation conferred the least resistance to quizalofop. The non-transgenic herbicide resistance trait identified will enhance weed control strategies in wheat.

  18. Comparative metabolic profiling of mce1 operon mutant vs wild-type Mycobacterium tuberculosis strains.

    Science.gov (United States)

    Queiroz, Adriano; Medina-Cleghorn, Daniel; Marjanovic, Olivera; Nomura, Daniel K; Riley, Lee W

    2015-11-01

    Mycobacterium tuberculosis disrupted in a 13-gene operon (mce1) accumulates free mycolic acids (FM) in its cell wall and causes accelerated death in mice. Here, to more comprehensively analyze differences in their cell wall lipid composition, we used an untargeted metabolomics approach to compare the lipid profiles of wild-type and mce1 operon mutant strains. By liquid chromatography-mass spectrometry, we identified >400 distinct lipids significantly altered in the mce1 mutant compared to wild type. These lipids included decreased levels of saccharolipids and glycerophospholipids, and increased levels of alpha-, methoxy- and keto mycolic acids (MA), and hydroxyphthioceranic acid. The mutant showed reduced expression of mmpL8, mmpL10, stf0, pks2 and papA2 genes involved in transport and metabolism of lipids recognized to induce proinflammatory response; these lipids were found to be decreased in the mutant. In contrast, the transcripts of mmpL3, fasI, kasA, kasB, acpM and RV3451 involved in MA transport and metabolism increased; MA inhibits inflammatory response in macrophages. Since the mce1 operon is known to be regulated in intracellular M. tuberculosis, we speculate that the differences we observed in cell wall lipid metabolism and composition may affect host response to M. tuberculosis infection and determine the clinical outcome of such an infection. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Role of active site rigidity in activity: MD simulation and fluorescence study on a lipase mutant.

    Directory of Open Access Journals (Sweden)

    Md Zahid Kamal

    Full Text Available Relationship between stability and activity of enzymes is maintained by underlying conformational flexibility. In thermophilic enzymes, a decrease in flexibility causes low enzyme activity while in less stable proteins such as mesophiles and psychrophiles, an increase in flexibility is associated with enhanced enzyme activity. Recently, we identified a mutant of a lipase whose stability and activity were enhanced simultaneously. In this work, we probed the conformational dynamics of the mutant and the wild type lipase, particularly flexibility of their active site using molecular dynamic simulations and time-resolved fluorescence techniques. In contrast to the earlier observations, our data show that active site of the mutant is more rigid than wild type enzyme. Further investigation suggests that this lipase needs minimal reorganization/flexibility of active site residues during its catalytic cycle. Molecular dynamic simulations suggest that catalytically competent active site geometry of the mutant is relatively more preserved than wild type lipase, which might have led to its higher enzyme activity. Our study implies that widely accepted positive correlation between conformation flexibility and enzyme activity need not be stringent and draws attention to the possibility that high enzyme activity can still be accomplished in a rigid active site and stable protein structures. This finding has a significant implication towards better understanding of involvement of dynamic motions in enzyme catalysis and enzyme engineering through mutations in active site.

  20. Overexpression of mutant ataxin-3 in mouse cerebellum induces ataxia and cerebellar neuropathology.

    Science.gov (United States)

    Nóbrega, Clévio; Nascimento-Ferreira, Isabel; Onofre, Isabel; Albuquerque, David; Conceição, Mariana; Déglon, Nicole; de Almeida, Luís Pereira

    2013-08-01

    Machado-Joseph disease (MJD), also known as spinocerebellar ataxia type 3 (SCA3), is a fatal, dominant neurodegenerative disorder caused by the polyglutamine-expanded protein ataxin-3. Clinical manifestations include cerebellar ataxia and pyramidal signs culminating in severe neuronal degeneration. Currently, there is no therapy able to modify disease progression. In the present study, we aimed at investigating one of the most severely affected brain regions in the disorder--the cerebellum--and the behavioral defects associated with the neuropathology in this region. For this purpose, we injected lentiviral vectors encoding full-length human mutant ataxin-3 in the mouse cerebellum of 3-week-old C57/BL6 mice. We show that circumscribed expression of human mutant ataxin-3 in the cerebellum mediates within a short time frame--6 weeks, the development of a behavioral phenotype including reduced motor coordination, wide-based ataxic gait, and hyperactivity. Furthermore, the expression of mutant ataxin-3 resulted in the accumulation of intranuclear inclusions, neuropathological abnormalities, and neuronal death. These data show that lentiviral-based expression of mutant ataxin-3 in the mouse cerebellum induces localized neuropathology, which is sufficient to generate a behavioral ataxic phenotype. Moreover, this approach provides a physiologically relevant, cost-effective and time-effective animal model to gain further insights into the pathogenesis of MJD and for the evaluation of experimental therapeutics of MJD.

  1. Silencing neuronal mutant androgen receptor in a mouse model of spinal and bulbar muscular atrophy.

    Science.gov (United States)

    Sahashi, Kentaro; Katsuno, Masahisa; Hung, Gene; Adachi, Hiroaki; Kondo, Naohide; Nakatsuji, Hideaki; Tohnai, Genki; Iida, Madoka; Bennett, C Frank; Sobue, Gen

    2015-11-01

    Spinal and bulbar muscular atrophy (SBMA), an adult-onset neurodegenerative disease that affects males, results from a CAG triplet repeat/polyglutamine expansions in the androgen receptor (AR) gene. Patients develop progressive muscular weakness and atrophy, and no effective therapy is currently available. The tissue-specific pathogenesis, especially relative pathological contributions between degenerative motor neurons and muscles, remains inconclusive. Though peripheral pathology in skeletal muscle caused by toxic AR protein has been recently reported to play a pivotal role in the pathogenesis of SBMA using mouse models, the role of motor neuron degeneration in SBMA has not been rigorously investigated. Here, we exploited synthetic antisense oligonucleotides to inhibit the RNA levels of mutant AR in the central nervous system (CNS) and explore its therapeutic effects in our SBMA mouse model that harbors a mutant AR gene with 97 CAG expansions and characteristic SBMA-like neurogenic phenotypes. A single intracerebroventricular administration of the antisense oligonucleotides in the presymptomatic phase efficiently suppressed the mutant gene expression in the CNS, and delayed the onset and progression of motor dysfunction, improved body weight gain and survival with the amelioration of neuronal histopathology in motor units such as spinal motor neurons, neuromuscular junctions and skeletal muscle. These findings highlight the importance of the neurotoxicity of mutant AR protein in motor neurons as a therapeutic target. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. The aba mutant of Arabidopsis thaliana is impaired in epoxy-carotenoid biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Rock, C.D.; Zeevaart, J.A.D. (Michigan State Univ., East Lansing (United States))

    1991-09-01

    The three mutant alleles of the ABA locus of Arabidopsis thaliana result in plants that are deficient in the plant growth regulator abscisic acid (ABA). The authors have used {sup 18}O{sub 2} to label ABA in water-stressed leaves of mutant and wild-type Arabidopsis. Analysis by selected ion monitoring and tandem mass spectrometry of ({sup 18}O)ABA and its catabolites, phaseic acid and ABA-glucose ester ({beta}-D-glucopyranosyl abscisate), indicates that the aba genotypes are impaired in ABA biosynthesis and have a small ABA precursor pool of compounds that contain oxygens on the rings, presumably oxygenated carotenoids (xanthophylls). Quantitation of the carotenoids form mutant and wild-type leaves establishes that the aba alleles cause a deficiency of the epoxy-carotenoids violaxanthin and neoxanthin and an accumulation of their biosynthetic precursor, zeaxanthin. These results provide evidence that ABA is synthesized by oxidative cleavage of epoxy-carotenoids (the indirect pathway). Furthermore the carotenoid mutant they describe undergoes normal greening. Thus the aba alleles provide an opportunity to study the physiological roles of epoxy-carotenoids in photosynthesis in a higher plants.

  3. Comparative Analyses of Transcriptional Profiles in Mouse Organs Using a Pneumonic Plague Model after Infection with Wild-Type Yersinia pestis CO92 and Its Braun Lipoprotein Mutant

    Directory of Open Access Journals (Sweden)

    Cristi L. Galindo

    2009-01-01

    Full Text Available We employed Murine GeneChips to delineate the global transcriptional profiles of the livers, lungs, and spleens in a mouse pneumonic plague infection model with wild-type (WT Y. pestis CO92 and its Braun lipoprotein (Δlpp mutant with reduced virulence. These organs showed differential transcriptional responses to infection with WT Y. pestis, but the overall host functional processes affected were similar across all three tissues. Gene expression alterations were found in inflammation, cytokine signaling, and apoptotic cell death-associated genes. Comparison of WT and Δlpp mutant-infected mice indicated significant overlap in lipopolysaccharide- (LPS- associated gene expression, but the absence of Lpp perturbed host cell signaling at critical regulatory junctions resulting in altered immune response and possibly host cell apoptosis. We generated a putative signaling pathway including major inflammatory components that could account for the synergistic action of LPS and Lpp and provided the mechanistic basis of attenuation caused by deletion of the lpp gene from Y. pestis in a mouse model of pneumonic plague.

  4. Evaluation of Drought response in Some Rice Mutant Lines Using Stress Tolerance Indices

    Directory of Open Access Journals (Sweden)

    H Aminpanah

    2018-05-01

    Full Text Available Introduction Drought is a major problem that limits the adoption of high-yielding rice varieties in drought-prone rainfed rice environments. To improve crop productivity, it is necessary to understand the mechanism of plant responses to drought conditions with the ultimate goal of improving crop performance in the vast areas of the world where rainfall is limiting or unreliable. Safaei Chaeikar et al. (2008 reported that MP, GMP, HM and STI indices, which showed the highest correlation with grain yield under both optimal and stress conditions, can be used as the best indices to introduce drought-tolerant genotypes in rice breeding programs. They also were introduced Nemat, Sepidrood, IR64, IR50 and Bejar genotypes as tolerant varieties. The present study was conducted to determine how drought affects grain yield in rice mutant lines and also to test this hypothesis in order to identify the most suitable indices/genotypes. Materials and Methods A field trial was conducted at Iranian Rice Research Centers in North of Iran, Rasht (latitude 37◦28', longitude 49◦28'E and altitude 7m below the sea level, during the 2014-2015 growing season. The seeds were sown in a nursery on the 10 May and 25 day old seedlings were transplanted to the field. Two separately experiment was carried out under reproductive stage drought stress and controlled conditions based on randomized complete block design with three replications, in four-row plots of three m length. Transplanting was done using 1 seedling per hill; at hill spacing of 25 cm × 25 cm. 18 rice genotypes were consisted 14 M5 mutant lines and their four parental cultivars. Results and Discussion Analysis of variance indicated significant effects of drought stress, genotype and interaction effects of two factors on grain yield, plant height, flag leaf area, tiller number and grain fertility percentage. Drought stress at reproductive stage caused reduction in grain yield (59.47%, grain fertility

  5. Marriage Matters: Spousal Similarity in Life Satisfaction

    OpenAIRE

    Ulrich Schimmack; Richard Lucas

    2006-01-01

    Examined the concurrent and cross-lagged spousal similarity in life satisfaction over a 21-year period. Analyses were based on married couples (N = 847) in the German Socio-Economic Panel (SOEP). Concurrent spousal similarity was considerably higher than one-year retest similarity, revealing spousal similarity in the variable component of life satisfac-tion. Spousal similarity systematically decreased with length of retest interval, revealing simi-larity in the changing component of life sati...

  6. Efficient Identification of Causal Mutations through Sequencing of Bulked F2 from Two Allelic Bloomless Mutants of Sorghum bicolor

    Directory of Open Access Journals (Sweden)

    Yinping Jiao

    2018-01-01

    Full Text Available Sorghum (Sorghum bicolor Moench, L. plant accumulates copious layers of epi-cuticular wax (EW on its aerial surfaces, to a greater extent than most other crops. EW provides a vapor barrier that reduces water loss, and is therefore considered to be a major determinant of sorghum's drought tolerance. However, little is known about the genes responsible for wax accumulation in sorghum. We isolated two allelic mutants, bloomless40-1 (bm40-1 and bm40-2, from a mutant library constructed from ethyl methane sulfonate (EMS treated seeds of an inbred, BTx623. Both mutants were nearly devoid of the EW layer. Each bm mutant was crossed to the un-mutated BTx623 to generated F2 populations that segregated for the bm phenotype. Genomic DNA from 20 bm F2 plants from each population was bulked for whole genome sequencing. A single gene, Sobic.001G228100, encoding a GDSL-like lipase/acylhydrolase, had unique homozygous mutations in each bulked F2 population. Mutant bm40-1 harbored a missense mutation in the gene, whereas bm40-2 had a splice donor site mutation. Our findings thus provide strong evidence that mutation in this GDSL-like lipase gene causes the bm phenotype, and further demonstrate that this approach of sequencing two independent allelic mutant populations is an efficient method for identifying causal mutations. Combined with allelic mutants, MutMap provides powerful method to identify all causal genes for the large collection of bm mutants in sorghum, which will provide insight into how sorghum plants accumulate such abundant EW on their aerial surface. This knowledge may facilitate the development of tools for engineering drought-tolerant crops with reduced water loss.

  7. Categories and inheritance of resistance to Nilaparvata lugens (Hemiptera: Delphacidae) in mutants of indica rice 'IR64'.

    Science.gov (United States)

    Sangha, Jatinder Singh; Chen, Yolanda H; Palchamy, Kadirvel; Jahn, Gary C; Maheswaran, M; Adalla, Candida B; Leung, Hei

    2008-04-01

    Varietal mutants can be useful for developing durable resistance, understanding categories of resistance, and identifying candidate genes involved in defense responses. We used mutants of rice 'IR64' to isolate new sources of resistance to the planthopper Nilaparvata lugens (Stål) (Hemiptera: Delphacidae). We compared two mutants that showed a gain and loss of resistance to N. lugens, to determine the categories of resistance to this pest. Under choice tests, female planthoppers avoided settling and laid fewer eggs on the resistant mutant 'D518' than on the susceptible mutant D1131, susceptible check 'TN1', and wild-type IR64, indicating that antixenosis was the resistance category. Similarly, under no-choice conditions, planthoppers laid 29% fewer eggs in D518 than in IR64, but they oviposited more in 'D1131' and TN1. Honeydew excretion was greater on D1131 seedlings but slightly lower on D518 than on IR64. Nymphal survival and adult female weight did not differ among rice cultivars. D518 showed higher tolerance of N. lugens infestations than IR64. Genetic analysis of the F1, F2, and F3 populations derived from D518 x IR64 revealed that resistance in D518 is dominant and controlled by a single gene. Despite the variation in resistance to N. lugens, both mutants and IR64 performed similarly in the field. The mutant D518 is a new source of durable resistance to N. lugens, mainly due to enhanced antixenosis to female hoppers for settling and oviposition.

  8. Photoproduct formation and repair capacity in a mutant of Bacillus cereus 569 producing UV-sensitive spores

    International Nuclear Information System (INIS)

    Weinberger, S.; Evenchik, Z.; Hertman, I.; Bar-Ilan Univ., Ramat-Gan

    1982-01-01

    A mutant of Bacillus cereus 569 UV sensitive in both vegetative and sporal stages was isolated by N-methyl-N'-nitro-N-nitrosoguanidine (NTG) mutagenesis followed by selection on mitomycin C. The UV-sensitive mutant designated as B. cereus 2422 exhibited normal content of dipicolinic acid (DPA) and resistance to X-rays and ethyl methanesulphonate. The photoproduct type and amount, induced by a given UV dose, was similar in either cells or spores of both the mutant 2422 and the wild-type ancestor. The mutant 2422 excised cyclobutane thymine dimers only to a limited extent (20%) as compared with 80% removal in the wild type. Removal of a spore-specific photoproduct (TDHT) during germination proceeded to a similar extent in B. cereus 2422 and the wild-type parent. However, under growing conditions, an additional removal of the TDHT was observed only in the wild-type strain. Liquid holding recovery occurred in irradiated wild-type cells, but not in mutant cells. Spontaneous revertants were isolated that regained UV resistance simultaneously in both the vegetative and sporal stage. (orig./AJ)

  9. Applications of Protein Thermodynamic Database for Understanding Protein Mutant Stability and Designing Stable Mutants.

    Science.gov (United States)

    Gromiha, M Michael; Anoosha, P; Huang, Liang-Tsung

    2016-01-01

    Protein stability is the free energy difference between unfolded and folded states of a protein, which lies in the range of 5-25 kcal/mol. Experimentally, protein stability is measured with circular dichroism, differential scanning calorimetry, and fluorescence spectroscopy using thermal and denaturant denaturation methods. These experimental data have been accumulated in the form of a database, ProTherm, thermodynamic database for proteins and mutants. It also contains sequence and structure information of a protein, experimental methods and conditions, and literature information. Different features such as search, display, and sorting options and visualization tools have been incorporated in the database. ProTherm is a valuable resource for understanding/predicting the stability of proteins and it can be accessed at http://www.abren.net/protherm/ . ProTherm has been effectively used to examine the relationship among thermodynamics, structure, and function of proteins. We describe the recent progress on the development of methods for understanding/predicting protein stability, such as (1) general trends on mutational effects on stability, (2) relationship between the stability of protein mutants and amino acid properties, (3) applications of protein three-dimensional structures for predicting their stability upon point mutations, (4) prediction of protein stability upon single mutations from amino acid sequence, and (5) prediction methods for addressing double mutants. A list of online resources for predicting has also been provided.

  10. Ectopic Mineralization and Conductive Hearing Loss in Enpp1asj Mutant Mice, a New Model for Otitis Media and Tympanosclerosis.

    Science.gov (United States)

    Tian, Cong; Harris, Belinda S; Johnson, Kenneth R

    2016-01-01

    Otitis media (OM), inflammation of the middle ear, is a common cause of hearing loss in children and in patients with many different syndromic diseases. Studies of the human population and mouse models have revealed that OM is a multifactorial disease with many environmental and genetic contributing factors. Here, we report on otitis media-related hearing loss in asj (ages with stiffened joints) mutant mice, which bear a point mutation in the Enpp1 gene. Auditory-evoked brainstem response (ABR) measurements revealed that around 90% of the mutant mice (Enpp1asj/asj) tested had moderate to severe hearing impairment in at least one ear. The ABR thresholds were variable and generally elevated with age. We found otitis media with effusion (OME) in all of the hearing-impaired Enpp1asj/asj mice by anatomic and histological examinations. The volume and inflammatory cell content of the effusion varied among the asj mutant mice, but all mutants exhibited a thickened middle ear epithelium with fibrous polyps and more mucin-secreting goblet cells than controls. Other abnormalities observed in the Enpp1 mutant mice include over-ossification at the round window ridge, thickened and over-calcified stapedial artery, fusion of malleus and incus, and white patches on the inside of tympanic membrane, some of which are typical symptoms of tympanosclerosis. An excessive yellow discharge was detected in the outer ear canal of older asj mutant mice, with 100% penetrance by 5 months of age, and contributes to the progressive nature of the hearing loss. This is the first report of hearing loss and ear pathology associated with an Enpp1 mutation in mice. The Enpp1asj mutant mouse provides a new animal model for studying tympanosclerotic otitis and otitis media with effusion, and also provides a specific model for the hearing loss recently reported to be associated with human ENPP1 mutations causing generalized arterial calcification of infancy and hypophosphatemic rickets.

  11. Mutant HABP2 Causes Non-Medullary Thyroid Cancer | Center for Cancer Research

    Science.gov (United States)

    The thyroid is a butterfly-shaped gland that lies at the base of the throat in front of the windpipe. A member of the endocrine system, the thyroid secretes hormones to regulate heart rate, blood pressure, temperature, and metabolism. Cancer of the thyroid is the most common endocrine cancer and the eighth most common cancer in the U.S. An estimated 63,450 Americans will be diagnosed with thyroid cancer this year. The vast majority is of follicular cell origin, and the remaining cancer originates from parafollicular cells, so called medullary thyroid cancer.

  12. Defining the cause of reduced progesterone levels during pregnancy in Kiss1/Gpr54 mutant mice

    OpenAIRE

    MILLÁN ESTEBAN, DAVID

    2015-01-01

    [ES] La kisspeptina, un neuropéptido codificado por el gen Kiss1, es requerida para la activación del eje reproductivo en la pubertad en los mamíferos y para el mantenimiento de la fertilidad en adultos. Los ratones que no tienen kisspeptina o que tienen mutaciones en el correspondiente receptor, GPR54, no entran en la pubertad y son estériles. Tienen gónadas subdesarrolladas (hipogonadismo), bajos niveles de hormona gonadotrópica (hipogonadotropismo), y bajos niveles de esteroides sexuales....

  13. Chloroplast Dysfunction Causes Multiple Defects in Cell Cycle Progression in the Arabidopsis crumpled leaf Mutant

    KAUST Repository

    Hudik, Elodie; Yoshioka, Yasushi; Domenichini, Sé Verine; Bourge, Mickaë l; Soubigout-Taconnat, Ludivine; Mazubert, Christelle; Yi, Dalong; Bujaldon, Sandrine; Hayashi, Hiroyuki; De Veylder, Lieven; Bergounioux, Catherine; Benhamed, Moussa; Raynaud, Cé cile

    2014-01-01

    The majority of research on cell cycle regulation is focused on the nuclear events that govern the replication and segregation of the genome between the two daughter cells. However, eukaryotic cells contain several compartmentalized organelles

  14. Mutant carbonic anhydrase 4 impairs pH regulation and causes retinal photoreceptor degeneration.

    NARCIS (Netherlands)

    Yang, Z.; Alvarez, B.V.; Chakarova, C.; Jiang, L.; Karan, G.; Frederick, J.M.; Zhao, Y.; Sauve, Y.; Li, X.; Zrenner, E.; Wissinger, B.; Hollander, A.I. den; Katz, B.; Baehr, W.; Cremers, F.P.M.; Casey, J.R.; Bhattacharya, S.S.; Zhang, K.

    2005-01-01

    Retina and retinal pigment epithelium (RPE) belong to the metabolically most active tissues in the human body. Efficient removal of acid load from retina and RPE is a critical function mediated by the choriocapillaris. However, the mechanism by which pH homeostasis is maintained is largely unknown.

  15. Main biological characters of series of mutant waxy rices developed from irradiation-induced mutation

    International Nuclear Information System (INIS)

    Huang Ronghua; Zhang Shubiao; Zhang Qingqi; Yang Rencui; Lin Jinhu

    2008-01-01

    The main biological characters of the waxy male sterile lines, maintainer lines, restorer lines and waxy hybrids which had been developed by radiation-induced mutation were studied, and the grain quality of the waxy hybrids were analyzed as well. Sesults indicated that the mutant waxy rice had the same growth duration, similar agronomic characters, panicle and spikelet traits as parent. The waxy male-sterile line had the same pollen sterility characteristic as its parent male-sterile line. The waxy hybrid rice retained the yield potential as original hybrid rice, and the grain quality of the waxy hybrids was similar to the conventional waxy rice Ejinnuo 6. (authors)

  16. Ontogenetically-regulated male sterility in tissue culture - induced and spontaneous sorghum mutants

    Directory of Open Access Journals (Sweden)

    Elkonin L.A.

    2003-01-01

    Full Text Available Variability of male fertility expression in the AS-1 line, a somaclonal variant obtained from tissue culture of CMS-plant, and in the progeny of revenant '124-1' obtained from fertile tiller, which developed on CMS-plant transferred from the field to the greenhouse, was investigated. Both revertants were characterized by similar expression of male fertility during plant ontogenesis: the panicle on the main tiller was almost completely sterile whereas formation of fertile pollen grains and seed set were observed on the panicles of the shoot tillers. A clear basipetal gradient of male fertility was manifested on all panicles: the base had significantly higher per cent of fertile pollen grains in comparison with the middle part, while in the top the anthers were either absent or had few sterile pollen grains. Such an ontogenetically-regulated restoration of male fertility was controlled by nuclear genes and could be transferred through the pollen in crosses with progenitor CMS-line. Growing of AS-1 plants in the growth chambers simultaneously under a long (16/8 and a short (12/12 daylength conditions demonstrated that differences of fertility level in different tillers was not caused by change of photoperiod during plant ontogenesis and functioning of photoperiod-sensitive fertility restoring gene. Whereas, the ontogenetically-regulated expression of male fertility in both revenants was temperature-dependent and was clearly manifested under relatively cool conditions during 2-week period before the beginning of anthesis of the first panicle (average daily temperature 21°C. The increase of the average daily temperature by 2-3 С resulted in sharp increase of male fertility level. Possibility of using AS-1 line in a new "two-line system" of hybrid seed production, which require only two lines (sterile mutant and fertility restorer, is discussed.

  17. Sleeping Beauty transposon mutagenesis identifies genes that cooperate with mutant Smad4 in gastric cancer development.

    Science.gov (United States)

    Takeda, Haruna; Rust, Alistair G; Ward, Jerrold M; Yew, Christopher Chin Kuan; Jenkins, Nancy A; Copeland, Neal G

    2016-04-05

    Mutations in SMAD4 predispose to the development of gastrointestinal cancer, which is the third leading cause of cancer-related deaths. To identify genes driving gastric cancer (GC) development, we performed a Sleeping Beauty (SB) transposon mutagenesis screen in the stomach of Smad4(+/-) mutant mice. This screen identified 59 candidate GC trunk drivers and a much larger number of candidate GC progression genes. Strikingly, 22 SB-identified trunk drivers are known or candidate cancer genes, whereas four SB-identified trunk drivers, including PTEN, SMAD4, RNF43, and NF1, are known human GC trunk drivers. Similar to human GC, pathway analyses identified WNT, TGF-β, and PI3K-PTEN signaling, ubiquitin-mediated proteolysis, adherens junctions, and RNA degradation in addition to genes involved in chromatin modification and organization as highly deregulated pathways in GC. Comparative oncogenomic filtering of the complete list of SB-identified genes showed that they are highly enriched for genes mutated in human GC and identified many candidate human GC genes. Finally, by comparing our complete list of SB-identified genes against the list of mutated genes identified in five large-scale human GC sequencing studies, we identified LDL receptor-related protein 1B (LRP1B) as a previously unidentified human candidate GC tumor suppressor gene. In LRP1B, 129 mutations were found in 462 human GC samples sequenced, and LRP1B is one of the top 10 most deleted genes identified in a panel of 3,312 human cancers. SB mutagenesis has, thus, helped to catalog the cooperative molecular mechanisms driving SMAD4-induced GC growth and discover genes with potential clinical importance in human GC.

  18. Histological and Molecular Characterization of Grape Early Ripening Bud Mutant

    Directory of Open Access Journals (Sweden)

    Da-Long Guo

    2016-01-01

    Full Text Available An early ripening bud mutant was analyzed based on the histological, SSR, and methylation-sensitive amplified polymorphism (MSAP analysis and a layer-specific approach was used to investigate the differentiation between the bud mutant and its parent. The results showed that the thickness of leaf spongy tissue of mutant (MT is larger than that of wild type (WT and the differences are significant. The mean size of cell layer L2 was increased in the mutant and the difference is significant. The genetic background of bud mutant revealed by SSR analysis is highly uniform to its parent; just the variations from VVS2 SSR marker were detected in MT. The total methylation ratio of MT is lower than that of the corresponding WT. The outside methylation ratio in MT is much less than that in WT; the average inner methylation ratio in MT is larger than that in WT. The early ripening bud mutant has certain proportion demethylation in cell layer L2. All the results suggested that cell layer L2 of the early ripening bud mutant has changed from the WT. This study provided the basis for a better understanding of the characteristic features of the early ripening bud mutant in grape.

  19. Gamma-ray induced mutants in castor (Ricinus communis L.)

    International Nuclear Information System (INIS)

    Janila, P.; Ashok Kumar, A.; Rajashekar Reddy, N.; Hemalatha, V.

    2007-01-01

    We report isolation of three recessive mutants in castor using dry seed irradiation with gamma rays. The crinkled leaf mutant (crf) was identified in K-55-112 M2 family and leafy mutant (lea) in H-55-577 M2 family; both are recessive lethal and thus maintained as heterozygotes. The cri mutant has highly wrinkled leaves resembling finger millet head and failed to enter reproductive phase, consequently did not produce seeds. The number of leaf lobes is reduced in lea mutant and though it produced spikes, the male and female flowers are converted to leafy appendages. The third mutant, fused (Ius) stem identified in H-55-617 M2 family is a recessive mutant. The branches of which are fused at the base and though each branch terminates in to monoceous spike like normal plant, the spike is highly condensed. The three mutants under report are valuable genetic stocks for development of linkage maps in castor, which is at infancy. (author)

  20. Development of Database Software with Plant Mutant Resources

    International Nuclear Information System (INIS)

    Namgoong, Won; Lee, M. J.; Kim, J. D.; Ma, N. K.

    2007-03-01

    In this research, mutants induced by nuclear radiation are developed information computerised system. The status and progress on the collection, identification and utilization of mutants in Korea are introduced. And it was produced home page, manual, test record, construction of system

  1. Clear Plaque Mutants of Lactococcal Phage TP901-1

    DEFF Research Database (Denmark)

    Kot, Witold; Kilstrup, Mogens; Vogensen, Finn K.

    2016-01-01

    We report a method for obtaining turbid plaques of the lactococcal bacteriophage TP901-1 and its derivative TP901-BC1034. We have further used the method to isolate clear plaque mutants of this phage. Analysis of 8 such mutants that were unable to lysogenize the host included whole genome...

  2. Isolation and characterization of stable mutants of Streptomyces

    Indian Academy of Sciences (India)

    Daunorubicin and its derivative doxorubicin are antitumour anthracycline antibiotics produced by Streptomyces peucetius. In this study we report isolation of stable mutants of S. peucetius blocked in different steps of the daunorubicin biosynthesis pathway. Mutants were screened on the basis of colony colour since producer ...

  3. Photosynthetic characterization of a rolled leaf mutant of rice ( Oryza ...

    African Journals Online (AJOL)

    A new rolling leaf rice mutant was identified which showed an apparently straighter longitudinal shape normal transverse rolling characters at all developing stages. The chlorophyll contents per fresh weight of this mutant leaves were lower than those of wild-type. The electron transfer rate (ETR) and photochemical ...

  4. Mutant strain of C. acetobutylicum and process for making butanol

    Science.gov (United States)

    Jain, Mahendra K.; Beacom, Daniel; Datta, Rathin

    1993-01-01

    A biologically pure asporogenic mutant of Clostridium acetobutylicum is produced by growing sporogenic C. acetobutylicum ATCC 4259 and treating the parent strain with ethane methane sulfonate. The mutant which as been designated C. acetobutylicum ATCC 55025 is useful in an improved ABE fermentation process, and produces high concentrations of butanol and total solvents.

  5. Sorghum Brown Midrib Mutants, Tools to Improve Biomass for Biofuels

    Science.gov (United States)

    To improve sorghum for cellulosic bioenergy uses, brown midrib mutants are being investigated for their ability to increase the conversion efficiency of biomass. brown midrib 6 and 12 (bmr6 and 12) mutants affect monolignol biosynthesis resulting in reduced lignin content and altered lignin composi...

  6. Isozyme patterns of powdery mildew resistant wheat mutants

    International Nuclear Information System (INIS)

    Xia Wengau; Li Zhengkui; Wang Kefeng

    1989-01-01

    Full Text: Wheat mutants induced by gamma irradiation and showing improved resistance to powdery mildew were analysed for isozymes. The peroxidase band 3A could be related to the disease reaction. The band 3A is absent in resistant mutants, the higher the activity of band 3A the greater the susceptibility. (author)

  7. Strain improvement in dye decolourising mutants of Mucor mucedo ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-12-15

    Dec 15, 2009 ... M. mucedo {MMM1-U.V. irradiated mutant and MMM2-EMS (ethyl methyl sulfonate) treated ... tions were induced and two positive mutants (MMM1, .... yeast biofilter for the treatment of a Nigerian fertilizer plant effluent. World J.

  8. Chinese hamster ovary cell mutants defective in heparan sulfate biosynthesis

    International Nuclear Information System (INIS)

    Bame, K.J.; Kiser, C.S.; Esko, J.D.

    1987-01-01

    The authors have isolated Chinese hamster ovary cell mutants defective in proteoglycan synthesis by radiographic screening for cells unable to incorporate 35 SO 4 into acid-precipitable material. Some mutants did not incorporate 35 SO 4 into acid-precipitable material, whereas others incorporated about 3-fold less radioactivity. HPLC anion exchange chromatographic analysis of radiolabelled glycosaminoglycans isolated from these mutants revealed many are defective in heparan sulfate biosynthesis. Mutants 803 and 677 do not synthesize heparan sulfate, although they produce chondroitin sulfate: strain 803 makes chondroitin sulfate normally, whereas 677 overaccumulates chondroitin sulfate by a factor of three. These mutants fall into the same complementation group, suggesting that the mutations are allelic. A second group of heparan sulfate biosynthetic mutants, consisting of cell lines 625, 668 and 679, produce undersulfated heparan sulfate and normal chondroitin sulfate. Treatment of the chains with nitrous acid should determine the position of the sulfate groups along the chain. These mutants may define a complementation group that is defective in the enzymes which modify the heparan sulfate chain. To increase the authors repertoire of heparan sulfate mutants, they are presently developing an in situ enzyme assay to screen colonies replica plated on filter discs for sulfotransferase defects

  9. Screening of in vitro derived mutants of banana against nematodes ...

    African Journals Online (AJOL)

    The rest of the mutants namely Ro Im V4 6-1-2 and Si Im V4 6-2-5 were found to be susceptible to nematodes. The resistant and moderately resistant mutants of banana could be further used in breeding programmes as well as being recognized as potential cultivars of commerce. Key words: Banana, nematode, resistance, ...

  10. Vasopressin increases S261 phosphorylation in AQP2-P262L, a mutant in recessive nephrogenic diabetes insipidus

    NARCIS (Netherlands)

    Trimpert, C.; van den Berg, D.T.; Fenton, R.A.; Klussmann, E.; Deen, P.M.T.

    2012-01-01

    Background Mutations in the aquaporin-2 (AQP2) gene cause nephrogenic diabetes insipidus (NDI), a renal disorder characterized by polyuria due to a lacking antidiuretic response to vasopressin. While most AQP2 mutants in recessive NDI are misfolded and retained in the endoplasmic reticulum,

  11. Characteristics of 36C103- influx into nitrate reductase deficient mutant E1 pisum sativum seedlings: evidence for restricted ''induction'' by nitrate compared with wild type

    International Nuclear Information System (INIS)

    Deane-Drummond, C.E.; Jacobsen, E.

    1986-01-01

    The characteristics of nitrate uptake into seedlings of Pisum sativum L. cv. Rondo mutant E 1 defective for nitrate reductase (NR) and of its parent variety Rondo have been investigated using 36 C10 3 - as an analogue for nitrate. The apparent Michaelis Menten constants (K m ) for 36 ClO 3 - influx measured over 10 min were similar for mutant E 1 and the wild type (Wt). There was a 28% increase in 36 C10 3 - into Wt seedlings following nitrate pretreatment but this was not found when mutant seedlings were used. N starvation increased 36 C10 3 - influx into both mutant and Wt seedlings, and the rate of cycling E/I was also enhanced to a similar extent. The results are discussed in terms of current ideas on the regulation of nitrate uptake and assimilation. (author)

  12. Reversion of autocrine transformation by a dominant negative platelet-derived growth factor mutant.

    Science.gov (United States)

    Vassbotn, F S; Andersson, M; Westermark, B; Heldin, C H; Ostman, A

    1993-07-01

    A non-receptor-binding mutant of the platelet-derived growth factor (PDGF) A chain, PDGF-0, was generated by exchanging 7 amino acids in the sequence. The mutant chains formed dimers that were similar to wild-type PDGF-AA with regard to stability and rate of processing to the mature 30-kDa secreted forms. Moreover, the mutant chains formed disulfide-bonded heterodimers with the PDGF B chain in NIH 3T3 cells heterodimer underwent the same processing and secretion as PDGF-AB. Transfection of c-sis-expressing 3T3 cells with PDGF-0 significantly inhibited the transformed phenotype of these cells, as determined by the following criteria. (i) Compared with PDGF-0-negative clones, PDGF-0-producing clones showed a reverted morphology. (ii) Clones producing PDGF-0 grew more slowly than PDGF-0-negative clones, with a fivefold difference in cell number after 14 days in culture. (iii) The expression of PDGF-0 completely inhibited the ability of the c-sis-expressing 3T3 cells to form colonies in soft agar; this inhibition was overcome by the addition of recombinant PDGF-BB to the culture medium, showing that the lack of colony formation of these cells was not due to a general unresponsiveness to PDGF. The specific expression of a PDGF-0/PDGF wild-type heterodimer in COS cells revealed that the affinity of the mutant heterodimer for the PDGF alpha receptor was decreased by approximately 50-fold compared with that of PDGF-AA. Thus, we show that a non-receptor-binding PDGF A-chain mutant neutralizes in a trans-dominant manner the autocrine transforming potential of the c-sis/PDGF B chain by forming low-affinity heterodimers with wild-type PDGF chains. This method of specifically antagonizing the effect of PDGF may be useful in investigations of the role of PDGF in normal and pathological conditions.

  13. Reduction of FR900525 using an S-(2-aminoethyl) l-cysteine-resistant mutant.

    Science.gov (United States)

    Shimizu, Shiho; Futase, Ayako; Yokoyama, Tatsuya; Ueda, Satoshi; Honda, Hiroyuki

    2017-06-01

    FK506 (tacrolimus), a macrolide compound with immunosuppressant activity, has been proven to have clinical importance and has been manufactured industrially since 1993 by using mutants with high FK506-production ability; these mutants have been developed from the wild strain Streptomyces tsukubaensis No. 9993. FR900525 is one of the by-products of FK506 production. However, there was no effective industrial method to separate FR900525 from FK506 due to the structural similarity between the two compounds. Therefore, reducing the level of FR900525 was a serious problem in the industrial strain A. In this study, we aimed to reduce the FR900525 production. We first determined that pipecolic acid level was a critical parameter for controlling FR900525 production in strain A. S-(2-Aminoethyl) l-cysteine (AEC)-resistant mutants has been reported to increase lysine productivity successfully in a variety of lysine-producing microorganisms. Therefore, next, we applied a selection of AEC-resistant mutants to enhance pipecolic acid biosynthesis. Finally, four AEC-resistant mutants were obtained from strain A using ultraviolet irradiation, and three of them showed less FR900525 productivity compared to the parental strain A. Our findings indicated that AEC resistance was effective phenotype marker for increasing pipecolic acid productivity and for reducing FR900525 production in S. tsukubaensis. Thus, our study provides an efficient method for reducing FR90025 level during FK506 biosynthesis. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  14. REASONS ANALYSIS OF THE «TOPOLINA» CATASTROPHE OCCURRENCE AND ACTIVITIES, EXCLUDING SIMILAR PHENOMENA IN DESIGNING AND CONSTRUCTION OF BUILDINGS AND STRUCTURES ON COLLAPSIBLE SOILS (to the 20th anniversary of disaster management. GENERAL PREREQUISITES FOR THE CAUSES FORMING OF “TOPOLINA” CATASTROPHE (PART 2

    Directory of Open Access Journals (Sweden)

    BOLSHAKOV V. I.

    2017-02-01

    Full Text Available It is presented historical information about the formation of the Dnepropetrovsk city council a new neighborhood – «Topol». The analysis of survey materials for the construction of new residential community «Topol-1», «Topol-2», «Topol-3» was made. Geotechnical and hydrogeological conditions of the area for construction of housing estate «Topol-1» were analyzed. The justification of the offered variants of the residential houses foundations under construction, social and cultural objects, submitted by project organization SPI «Ukrspetsstroyproekt» are given. We analyzed the design decisions UMZ residential complex foundations along the Zaporozhskoe shosse street. It was disclosed forced replacement of the proposed variant of pile foundation under the projected SPI «Giprograd», housing estate on another version of foundations on the artificial basis after the transfer of the construction site from the second type to the first type of ground conditions by subsidence. It is given a brief justification of the flooding onset of the already exploited residential construction during the preliminary soaking of the territory for the residential complex UMZ. It is also revealed the reason for the occurrence of supranational deformations of the basements, foundations and structures of the lightest buildings of pre-school children's institutions, which are in operation before the preliminary soaking of the UMZ residential complex territory. The suffosion processes occurrence on the territory of the Topol-1 residential area, connected with the unloading occurrence of groundwater and increasing of the pressure gradient, decompaction and weakening of the soils of the second slope of the «Vstrechnaya» beam is substantiated. The cause of the hydraulic breakthrough of the destroyed second slope of the «Vstrechnaya» beam and the consequences that follow from this was disclosed. It is shown errors in purpose of SE «DneproNIISP» taking into

  15. Tumor suppressor PTEN affects tau phosphorylation: deficiency in the phosphatase activity of PTEN increases aggregation of an FTDP-17 mutant Tau

    Directory of Open Access Journals (Sweden)

    Zhang Xue

    2006-07-01

    Full Text Available Abstract Background Aberrant hyperphosphorylation of tau protein has been implicated in a variety of neurodegenerative disorders. Although a number of protein kinases have been shown to phosphorylate tau in vitro and in vivo, the molecular mechanisms by which tau phosphorylation is regulated pathophysiologically are largely unknown. Recently, a growing body of evidence suggests a link between tau phosphorylation and PI3K signaling. In this study, phosphorylation, aggregation and binding to the microtubule of a mutant frontal temporal dementia and parkinsonism linked to chromosome 17 (FTDP-17 tau in the presence of tumor suppressor PTEN, a major regulatory component in PI3K signaling, were investigated. Results Phosphorylation of the human mutant FTDP-17 tau, T40RW, was evaluated using different phospho-tau specific antibodies in the presence of human wild-type or phosphatase activity null mutant PTEN. Among the evaluated phosphorylation sites, the levels of Ser214 and Thr212 phospho-tau proteins were significantly decreased in the presence of wild-type PTEN, and significantly increased when the phosphatase activity null mutant PTEN was ectopically expressed. Fractionation of the mutant tau transfected cells revealed a significantly increased level of soluble tau in cytosol when wild-type PTEN was expressed, and an elevated level of SDS-soluble tau aggregates in the presence of the mutant PTEN. In addition, the filter/trap assays detected more SDS-insoluble mutant tau aggregates in the cells overexpressing the mutant PTEN compared to those in the cells overexpressing wild-type PTEN and control DNA. This notion was confirmed by the immunocytochemical experiment which demonstrated that the overexpression of the phosphatase activity null mutant PTEN caused the mutant tau to form aggregates in the COS-7 cells. Conclusion Tumor suppressor PTEN can alleviate the phosporylation of the mutant FTDP-17 tau at specific sites, and the phosphatase activity

  16. Comparative studies on physical-chemical properties and major nutritional components of rice grain in dwarf mutant resistant to insect pests and its parent

    International Nuclear Information System (INIS)

    Cui Hairui; Wu Dianxing; Shen Shengquan; Shu Qingyao

    2004-01-01

    Starch characteristics and key nutritional compositions in the dwarf mutant from transgenic rice with crylAb gene were compared with its original parent, Xiushuill. It was found that peak viscosity, hot paste viscosity and cool paste viscosity of RVA profile between the dwarf mutant and its parent were significantly different at 1% level, but apparent amylose content, gel consistence existed and breakdown viscosity of RVA profile were similar, and no significant differences existed in contents of crude protein, crude fat, total ash, amino acids and mineral compositions. It was suggested that no notable changes occurred in grain quality traits in the dwarf mutant with insect resistance. (authors)

  17. Induction and characterization of Arabidopsis mutants by Ion beam

    International Nuclear Information System (INIS)

    Yoon, Y. H.; Choi, J. D.; Park, J. Y.; Lee, J. R.; Sohn, H. S.

    2008-03-01

    This study was conducted to search the proper conditions and times for irradiating proton beam to seeds generally used for induction of mutant. Arabidopsis as model plants has good characters that is a short generation time, producing a lot of seeds, sequenced genome, developed maker. This points were the best materials for plant breeding for this study. The data of inducing mutants of Arabidopsis is used to be applicate to crops have more longer generation that is the final goals of this study. The goals of this project were to inducing and characterizing arabidopsis mutants by the proton ion beam and γ-ray. As well as, the purpose of this study was securing more than 10 lines of arabidopsis mutants in this project and also to know the changed DNA structure of the mutants using the basic data for applying to the more study

  18. Spectrum of mutant characters utilized in developing improved cultivars

    International Nuclear Information System (INIS)

    Donini, B.; Kawai, T.; Micke, A.

    1984-01-01

    Although about 500 cultivars are known to have been developed by using induced mutations, the range of mutant traits seems to be rather narrow. Mutant traits have mostly been used that can be detected visually on an individual plant basis. However, in the background of such mutants other valuable mutations have been found in later generations. In cross-breeding with mutants valuable characteristics occurred, which could not be predicted from the phenotypes of the parents. It is concluded that improved attributes in the released mutant varieties do not comprise the entire genetic variation that could derive from mutagenesis. Current selection techniques are inadequate to exploit the full potential of mutagenesis for plant breeding. (author)

  19. Mildew resistant and less lodging wheat mutants induced in Iran

    International Nuclear Information System (INIS)

    Naghedi-Ahmadi, I.

    1989-01-01

    ''Tabassi'' is a lodging and mildew susceptible cultivar. To induce mutations, seeds were gamma irradiated (50 to 150 Gy) in 1982 and selection for lodging resistance was carried out in M 2 . During field experiments with the mutant lines in 1985/86 there has been a heavy mildew epidemic under which mutant 63-5-I (derived from 50 Gy treatment) exhibited considerable resistance and as a consequence, higher yield. The control was 100% infected, the mutant only 40%. The mutant yielded 31% more grain, 7.5% less straw and 4.5% more protein than the control. Lodging of 63-5-I was only 60% in an experiment under rainfed conditions in the same season, resulting in a relative yield increase of about 11%. In 1986/87 there was no mildew epidemic and the mutant yielded the same as ''Tabassi''

  20. Characteristics of mutant lines of sweet potato flour

    International Nuclear Information System (INIS)

    Aryanti

    2012-01-01

    Research on mutation induction of sweet potato Sari variety has been conducted. Flour mutant lines were obtained from selection of M1V5 tubers irradiated by gamma rays at the dose of 10 Gy. Flour was made by peeling of tubers, then dried, blended and sieved. The quality test of flour have been done by measuring degree of whiteness, proximate, amylose contents, water content, soluble water, swelling power, and flour characteristics. The result of this work showed that flour of C6.26.13 mutant line had higher protein content than the parent plant with concentration of 3.62 % and its amylose content was also higher than the other mutant lines. The soluble water value of mutant lines were significant different compared to the parent plant from 1.82 to 2.25 % and swelling power from 4.28 to 5.55 %. The flour granule of the mutant line was different compared to the parent plant. (author)

  1. Photosynthetic and nitrogen fixation capability in several soybean mutant lines

    International Nuclear Information System (INIS)

    Gandanegara, S.; Hendratno, K.

    1987-01-01

    Photosynthetic and nitrogen fixation capability in several soybean mutant lines. A greenhouse experiment has been carried out to study photosynthetic and nitrogen fixation capability of five mutant lines and two soybean varieties. An amount of 330 uCi of 14 CO 2 was fed to the plants including of the non-fixing reference crop (Chippewa non-nodulating isoline). Nitrogen fixation measurements was carried out using 15 N isotope dilution technique according to A-value concept. Results showed that beside variety/mutant lines, plant growth also has important role in photosynthetic and N fixing capability. Better growth and a higher photosynthetic capability in Orba, mutant lines nos. 63 and 65 resulted in a greater amount of N 2 fixed (mg N/plant) than other mutant lines. (author). 12 refs.; 5 figs

  2. Induction and characterization of Arabidopsis mutants by Ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Y. H.; Choi, J. D.; Park, J. Y.; Lee, J. R.; Sohn, H. S. [Gyeongbuk Institute for Bio Industry, Andong (Korea, Republic of)

    2008-03-15

    This study was conducted to search the proper conditions and times for irradiating proton beam to seeds generally used for induction of mutant. Arabidopsis as model plants has good characters that is a short generation time, producing a lot of seeds, sequenced genome, developed maker. This points were the best materials for plant breeding for this study. The data of inducing mutants of Arabidopsis is used to be applicate to crops have more longer generation that is the final goals of this study. The goals of this project were to inducing and characterizing arabidopsis mutants by the proton ion beam and {gamma}-ray. As well as, the purpose of this study was securing more than 10 lines of arabidopsis mutants in this project and also to know the changed DNA structure of the mutants using the basic data for applying to the more study

  3. Early transcriptional responses of internalization defective Brucella abortus mutants in professional phagocytes, RAW 264.7.

    Science.gov (United States)

    Cha, Seung Bin; Lee, Won Jung; Shin, Min Kyoung; Jung, Myung Hwan; Shin, Seung Won; Yoo, An Na; Kim, Jong Wan; Yoo, Han Sang

    2013-06-27

    Brucella abortus is an intracellular zoonotic pathogen which causes undulant fever, endocarditis, arthritis and osteomyelitis in human and abortion and infertility in cattle. This bacterium is able to invade and replicate in host macrophage instead of getting removed by this defense mechanism. Therefore, understanding the interaction between virulence of the bacteria and the host cell is important to control brucellosis. Previously, we generated internalization defective mutants and analyzed the envelope proteins. The present study was undertaken to evaluate the changes in early transcriptional responses between wild type and internalization defective mutants infected mouse macrophage, RAW 264.7. Both of the wild type and mutant infected macrophages showed increased expression levels in proinflammatory cytokines, chemokines, apoptosis and G-protein coupled receptors (Gpr84, Gpr109a and Adora2b) while the genes related with small GTPase which mediate intracellular trafficking was decreased. Moreover, cytohesin 1 interacting protein (Cytip) and genes related to ubiquitination (Arrdc3 and Fbxo21) were down-regulated, suggesting the survival strategy of this bacterium. However, we could not detect any significant changes in the mutant infected groups compared to the wild type infected group. In summary, it was very difficult to clarify the alterations in host cellular transcription in response to infection with internalization defective mutants. However, we found several novel gene changes related to the GPCR system, ubiquitin-proteosome system, and growth arrest and DNA damages in response to B. abortus infection. These findings may contribute to a better understanding of the molecular mechanisms underlying host-pathogen interactions and need to be studied further.

  4. Loss of circadian clock accelerates aging in neurodegeneration-prone mutants.

    Science.gov (United States)

    Krishnan, Natraj; Rakshit, Kuntol; Chow, Eileen S; Wentzell, Jill S; Kretzschmar, Doris; Giebultowicz, Jadwiga M

    2012-03-01

    Circadian clocks generate rhythms in molecular, cellular, physiological, and behavioral processes. Recent studies suggest that disruption of the clock mechanism accelerates organismal senescence and age-related pathologies in mammals. Impaired circadian rhythms are observed in many neurological diseases; however, it is not clear whether loss of rhythms is the cause or result of neurodegeneration, or both. To address this important question, we examined the effects of circadian disruption in Drosophila melanogaster mutants that display clock-unrelated neurodegenerative phenotypes. We combined a null mutation in the clock gene period (per(01)) that abolishes circadian rhythms, with a hypomorphic mutation in the carbonyl reductase gene sniffer (sni(1)), which displays oxidative stress induced neurodegeneration. We report that disruption of circadian rhythms in sni(1) mutants significantly reduces their lifespan compared to single mutants. Shortened lifespan in double mutants was coupled with accelerated neuronal degeneration evidenced by vacuolization in the adult brain. In addition, per(01)sni(1) flies showed drastically impaired vertical mobility and increased accumulation of carbonylated proteins compared to age-matched single mutant flies. Loss of per function does not affect sni mRNA expression, suggesting that these genes act via independent pathways producing additive effects. Finally, we show that per(01) mutation accelerates the onset of brain pathologies when combined with neurodegeneration-prone mutation in another gene, swiss cheese (sws(1)), which does not operate through the oxidative stress pathway. Taken together, our data suggest that the period gene may be causally involved in neuroprotective pathways in aging Drosophila. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Defective processing of methylate