WorldWideScience

Sample records for resistance related protein

  1. Multiple drug resistance protein (MDR-1, multidrug resistance-related protein (MRP and lung resistance protein (LRP gene expression in childhood acute lymphoblastic leukemia

    Directory of Open Access Journals (Sweden)

    Elvis Terci Valera

    Full Text Available CONTEXT: Despite the advances in the cure rate for acute lymphoblastic leukemia, approximately 25% of affected children suffer relapses. Expression of genes for the multiple drug resistance protein (MDR-1, multidrug resistance-related protein (MRP, and lung resistance protein (LRP may confer the phenotype of resistance to the treatment of neoplasias. OBJECTIVE: To analyze the expression of the MDR-1, MRP and LRP genes in children with a diagnosis of acute lymphoblastic leukemia via the semiquantitative reverse transcription polymerase chain reaction (RT-PCR, and to determine the correlation between expression and event-free survival and clinical and laboratory variables. DESIGN: A retrospective clinical study. SETTING: Laboratory of Pediatric Oncology, Department of Pediatrics, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Brazil. METHODS: Bone marrow aspirates from 30 children with a diagnosis of acute lymphoblastic leukemia were assessed for the expression of messenger RNA for the MDR-1, MRP and LRP genes by semi-quantitative RT-PCR. RESULTS: In the three groups studied, only the increased expression of LRP was related to worsened event-free survival (p = 0.005. The presence of the common acute lymphoblastic leukemia antigen (CALLA was correlated with increased LRP expression (p = 0.009 and increased risk of relapse or death (p = 0.05. The relative risk of relapse or death was six times higher among children with high LRP expression upon diagnosis (p = 0.05, as confirmed by multivariate analysis of the three genes studied (p = 0.035. DISCUSSION: Cell resistance to drugs is a determinant of the response to chemotherapy and its detection via RT-PCR may be of clinical importance. CONCLUSIONS: Evaluation of the expression of genes for resistance to antineoplastic drugs in childhood acute lymphoblastic leukemia upon diagnosis, and particularly the expression of the LRP gene, may be of clinical relevance, and should be the

  2. Induced systemic resistance in radish is not associated with accumulation of pathogenesis-related proteins

    NARCIS (Netherlands)

    Hoffland, E.; Pieterse, C.M.J.; Bik, L.; Pelt, J.A. van den

    1995-01-01

    The non-pathogenic Pseudomonas fluorescens strain WCS417r has been shown to induce systemic resistance in radish against Fusarium oxysporum f.sp. raphani. In this paper we investigate the involvement of pathogenesis-related (PR) proteins in this Pseudomonas-induced resistance. For comparison, salicy

  3. Comparative proteomic analysis reveals mite (Varroa destructor) resistance-related proteins in Eastern honeybees (Apis cerana).

    Science.gov (United States)

    Ji, T; Shen, F; Liu, Z; Yin, L; Shen, J; Liang, Q; Luo, Y X

    2015-08-21

    The mite (Varroa destructor) has become the greatest threat to apiculture worldwide. As the original host of the mite, Apis cerana can effectively resist the mite. An increased understanding of the resistance mechanisms of Eastern honeybees against V. destructor may help researchers to protect other species against these parasites. In this study, the proteomes of 4 Apis cerana colonies were analyzed using an isobaric tag for relative and absolute quantitation technology. We determined the differences in gene and protein expression between susceptible and resistant colonies that were either unchallenged or challenged by V. destructor. The results showed that a total of 1532 proteins were identified. Gene Ontology enrichment analysis suggested that the transcription factors and basic metabolic and respiratory processes were efficient and feasible factors controlling this resistance, and 12 differentially expressed proteins were identified in Venn analysis. The results were validated by quantitative polymerase chain reaction. This study may provide insight into the genetic mechanisms underlying the resistance of honeybee to mites.

  4. Expression and cellular distribution of multidrug resistance-related proteins in the hippocampus of patients with mesial temporal lobe epilepsy

    NARCIS (Netherlands)

    E. Aronica; J.A. Gorter; M. Ramkema; S. Redeker; F. Ozbas-Gercer; E.A. van Vliet; G.L. Scheffer; R.J. Scheper; P. van der Valk; J.C. Baayen; D. Troost

    2004-01-01

    Purpose: This study investigated the cellular distribution of different multidrug resistance (MDR)-related proteins such as P-glycoprotein (P-gp), the multidrug resistance-associated proteins (MRP) 1 and 2, and the major vault protein (MVP) in normal and sclerotic hippocampus of patients with medica

  5. Toxicological relevance of the multidrug resistance protein 1, MRP1 (ABCC1) and related transporters.

    Science.gov (United States)

    Leslie, E M; Deeley, R G; Cole, S P

    2001-10-05

    The 190 kDa multidrug resistance protein 1 (MRP1/ABCC1) is a founding member of a subfamily of the ATP binding cassette (ABC) superfamily of transport proteins and was originally identified on the basis of its elevated expression in multidrug resistant lung cancer cells. In addition to its ability to confer resistance in tumour cells, MRP1 is ubiquitously expressed in normal tissues and is a primary active transporter of GSH, glucuronate and sulfate conjugated and unconjugated organic anions of toxicological relevance. Substrates include lipid peroxidation products, herbicides, tobacco specific nitrosamines, mycotoxins, heavy metals, and natural product and antifolate anti-cancer agents. MRP1 also transports unmodified xenobiotics but often requires GSH to do so. Active efflux is generally an important aspect of cellular detoxification since it prevents the accumulation of conjugated and unconjugated compounds that have the potential to be directly toxic. The related transporters MRP2 and MRP3 have overlapping substrate specificities with MRP1 but different tissue distributions, and evidence that they also have chemoprotective functions are discussed. Finally, MRP homologues have been described in other species including yeast and nematodes. Those isolated from the vascular plant Arabidopsis thaliana (AtMRPs) decrease the cytoplasmic concentration of conjugated toxins through sequestration in vacuoles and are implicated in providing herbicide resistance to plants.

  6. Differential expression of sphingolipids in P-glycoprotein or multidrug resistance-related protein 1 expressing human neuroblastoma cell lines

    NARCIS (Netherlands)

    Dijkhuis, AJ; Douwes, J; Kamps, W; Sietsma, H; Kok, JW

    2003-01-01

    The sphingolipid composition and multidrug resistance status of three human neuroblastoma cell lines were established. SK-N-FI cells displayed high expression and functional (efflux) activity of P-glycoprotein, while multidrug resistance-related protein 1 was relatively abundant and most active in S

  7. Differential expression of sphingolipids in P-glycoprotein or multidrug resistance-related protein 1 expressing human neuroblastoma cell lines

    NARCIS (Netherlands)

    Dijkhuis, AJ; Douwes, J; Kamps, W; Sietsma, H; Kok, JW

    2003-01-01

    The sphingolipid composition and multidrug resistance status of three human neuroblastoma cell lines were established. SK-N-FI cells displayed high expression and functional (efflux) activity of P-glycoprotein, while multidrug resistance-related protein 1 was relatively abundant and most active in

  8. Ontogeny, aging, and gender-related changes in hepatic multidrug resistant protein genes in rats.

    Science.gov (United States)

    Zhu, Qiong-Ni; Hou, Wei-Yu; Xu, Shang-Fu; Lu, Yuan-Fu; Liu, Jie

    2017-02-01

    Multidrug resistance proteins (Mrps) are efflux transporters playing important roles in endogenous substances and xenobiotics transport out of the liver. Children, elderly, gender and physio-pathological conditions could influence their expression and result in changes in drug disposition.

  9. Relation of Absolute or Relative Adiposity to Insulin Resistance, Retinol Binding Protein-4, Leptin, and Adiponectin in Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    You Lim Kim

    2012-12-01

    Full Text Available BackgroundCentral fat mass (CFM correlates with insulin resistance and increases the risk of type 2 diabetes and cardiovascular complications; however, peripheral fat mass (PFM is associated with insulin sensitivity. The aim of this study was to investigate the relation of absolute and relative regional adiposity to insulin resistance index and adipokines in type 2 diabetes.MethodsTotal of 83 overweighted-Korean women with type 2 diabetes were enrolled, and rate constants for plasma glucose disappearance (KITT and serum adipokines, such as retinol binding protein-4 (RBP4, leptin, and adiponectin, were measured. Using dual X-ray absorptiometry, trunk fat mass (in kilograms was defined as CFM, sum of fat mass on the lower extremities (in kilograms as PFM, and sum of CFM and PFM as total fat mass (TFM. PFM/TFM ratio, CFM/TFM ratio, and PFM/CFM ratio were defined as relative adiposity.ResultsMedian age was 55.9 years, mean body mass index 27.2 kg/m2, and mean HbA1c level 7.12±0.84%. KITT was positively associated with PMF/TFM ratio, PMF/CFM ratio, and negatively with CFM/TFM ratio, but was not associated with TFM, PFM, or CFM. RBP4 levels also had a significant relationship with PMF/TFM ratio and PMF/CFM ratio. Adiponectin, leptin, and apolipoprotein A levels were related to absolute adiposity, while only adiponectin to relative adiposity. In correlation analysis, KITT in type 2 diabetes was positively related with HbA1c, fasting glucose, RBP4, and free fatty acid.ConclusionThese results suggest that increased relative amount of peripheral fat mass may aggravate insulin resistance in type 2 diabetes.

  10. Expression of multidrug resistance-associated proteins in rhabdomyosarcomas before and after chemotherapy : The relationship between lung resistance-related protein (LRP) and differentiation

    NARCIS (Netherlands)

    Klunder, JW; Komdeur, R; van der Graaf, WTA; de Bont, EJSM; Hoekstra, HJ; van den Berg, E; Molenaar, WM

    Rhabdomyosarcomas generally respond well to chemotherapy, and the residual lesions often are better differentiated than their primaries. This phenomenon may be explained by selective multidrug resistance (MDR) of differentiated tumor cell populations. We assess the role of MDR proteins in

  11. Target and resistance-related proteins of recombinant mutant human tumor necrosis factor-related apoptosis-inducing ligand on myeloma cell lines.

    Science.gov (United States)

    Jian, Yuan; Chen, Yuling; Geng, Chuanying; Liu, Nian; Yang, Guangzhong; Liu, Jinwei; Li, Xin; Deng, Haiteng; Chen, Wenming

    2016-06-01

    Recombinant mutant human tumor necrosis factor-related apoptosis-inducing ligand (rmhTRAIL) has become a potential therapeutic drug for multiple myeloma (MM). However, the exact targets and resistance mechanisms of rmhTRAIL on MM cells remain to be elucidated. The present study aimed to investigate the target and resistance-related proteins of rmhTRAIL on myeloma cell lines. A TRAIL-sensitive myeloma cell line, RPMI 8226, and a TRAIL-resistance one, U266, were chosen and the differentially expressed proteins between the two cell lines were analyzed prior and subsequent to rmhTRAIL administration by a liquid chromatography-tandem mass spectrometry method. The results showed that following TRAIL treatment, 6 apoptosis-related proteins, calpain small subunit 1 (CPNS1), peflin (PEF1), B-cell receptor-associated protein 31 (BAP31), apoptosis-associated speck-like protein containing CARD (ASC), BAG family molecular chaperone regulator 2 (BAG2) and chromobox protein homolog 3 (CBX3), were upregulated in RPMI 8226 cells while no change was identified in the U266 cells. Furthermore, small ubiquitin-related modifier 1 and several other ubiquitin proteasome pathway (UPP)-related proteins expressed higher levels in TRAIL-resistant cells U266 compared to the RPMI-8226 cells prior and subsequent to rmhTRAIL treatment. These results suggested that CPNS1, PEF1, BAP31, ASC, BAG2 and CBX3 were possibly target proteins of rmhTRAIL on RPMI 8226 cells, while UPP may have a vital role in mediating TRAIL-resistance in U266 cells.

  12. Target and resistance-related proteins of recombinant mutant human tumor necrosis factor-related apoptosis-inducing ligand on myeloma cell lines

    OpenAIRE

    JIAN, YUAN; Chen, Yuling; GENG, CHUANYING; Liu, Nian; YANG, GUANGZHONG; Liu, Jinwei; Li, Xin; Deng, Haiteng; CHEN, WENMING

    2016-01-01

    Recombinant mutant human tumor necrosis factor-related apoptosis-inducing ligand (rmhTRAIL) has become a potential therapeutic drug for multiple myeloma (MM). However, the exact targets and resistance mechanisms of rmhTRAIL on MM cells remain to be elucidated. The present study aimed to investigate the target and resistance-related proteins of rmhTRAIL on myeloma cell lines. A TRAIL-sensitive myeloma cell line, RPMI 8226, and a TRAIL-resistance one, U266, were chosen and the differentially ex...

  13. A potato pathogenesis-related protein gene, StPRp27, contributes to race-nonspecific resistance against Phytophthora infestans.

    Science.gov (United States)

    Shi, Xiaolei; Tian, Zhendong; Liu, Jun; van der Vossen, Edwin A G; Xie, Conghua

    2012-02-01

    Late blight caused by Phytophthora infestans is the most important disease of potato. Many efforts have been made to understand molecular mechanism of the durable resistance to address the challenge raised by rapid evolution of the pathogen. A pathogenesis related protein (PR) gene StPRp27 was previously isolated from the potato leaves challenged by P. infestans. The sequence analysis and expression pattern reveal that StPRp27 may be associated with resistance to P. infestans. In present research, transient expression of StPRp27 in Nicotiana benthamiana enhanced resistance to P. infestans isolates 99189 and PY23 indicating its potential contribution to the disease resistance. These findings were also confirmed by over-expression of StPRp27 in potato cv. E-potato 3, which significantly slowed down the development of the disease after inoculation with a mixture of P. infestans races. Further, silencing of StPRp27 homologous genes in N. benthamiana harboring dominant Phytophthora resistance gene Rpi-blb1 or Rpi-blb2 showed no effects on the resistance triggered by these R genes. Our results suggest that StPRp27 contributes to a race-nonspecific resistance against P. infestans by inhibiting the disease development and has a potential use in selection and breeding for durable resistance to late blight.

  14. Ageing has no effect on the regulation of the ubiquitin proteasome-related genes and proteins following resistance exercise

    Directory of Open Access Journals (Sweden)

    Renae Jane Stefanetti

    2014-01-01

    Full Text Available Skeletal muscle atrophy is a critical component of the ageing process. Age-related muscle wasting is due to disrupted muscle protein turnover, a process mediated in part by the ubiquitin proteasome pathway (UPP. Additionally, older subjects have been observed to have an attenuated anabolic response, at both the molecular and physiological levels, following a single-bout of resistance exercise (RE. We investigated the expression levels of the UPP-related genes and proteins involved in muscle protein degradation in 10 older (60-75 years versus 10 younger (18-30 years healthy male subjects at basal as well as 2 hours after a single-bout of RE. MURF1, atrogin-1 and FBXO40, their substrate targets PKM2, myogenin, MYOD, MHC and EIF3F as well as MURF1 and atrogin-1 transcriptional regulators FOXO1 and FOXO3 gene and/or protein expression levels were measured via real time PCR and western blotting, respectively. At basal, no age-related difference was observed in the gene/protein levels of atrogin-1, MURF1, myogenin, MYOD and FOXO1/3. However, a decrease in FBXO40 mRNA and protein levels was observed in older subjects, while PKM2 protein was increased in older subjects. In response to RE, MURF1, atrogin-1 and FBXO40 mRNA were upregulated in both the younger and older subjects, with changes observed in protein levels. In conclusion, UPP-related gene/protein expression is comparably regulated in healthy young and old male subjects at basal and following RE. These findings suggest that UPP signalling plays a limited role in the process of age-related muscle wasting. Future studies are required to investigate additional proteolytic mechanisms in conjunction with skeletal muscle protein breakdown measurements following RE in older versus younger subjects.

  15. Induced resistance in plants and the role of pathogenesis-related proteins

    NARCIS (Netherlands)

    Loon, L.C. van

    2001-01-01

    The nature of induced resistance Resistance, according to Agrios (1988) is the ability of an organism to exclude or overcome, completely or in some degree, the effect of a pathogen or other damaging factor. Disease resistance in plants is manifested by limited symptoms, reflecting the inability of t

  16. Nuclear multidrug-resistance related protein 1 contributes to multidrug-resistance of mucoepidermoid carcinoma mainly via regulating multidrug-resistance protein 1: a human mucoepidermoid carcinoma cells model and Spearman's rank correlation analysis.

    Directory of Open Access Journals (Sweden)

    Bolei Cai

    Full Text Available BACKGROUND: Multidrug resistance-related protein 1 (MRP1/ABCC1 and multidrug resistance protein 1 (MDR1/P-glycoprotein/ABCB1 are both membrane-bound drug transporters. In contrast to MDR1, MRP1 also transports glutathione (GSH and drugs conjugated to GSH. Due to its extraordinary transport properties, MRP1/ABCC1 contributes to several physiological functions and pathophysiological incidents. We previously found that nuclear translocation of MRP1 contributes to multidrug-resistance (MDR of mucoepidermoid carcinoma (MEC. The present study investigated how MRP1 contributes to MDR in the nuclei of MEC cells. METHODS: Western blot and RT-PCR was carried out to investigate the change of multidrug-resistance protein 1 (MDR1 in MC3/5FU cells after MRP1 was downregulated through RNA interference (RNAi. Immunohistochemistry (IHC staining of 127 cases of MEC tissues was scored with the expression index (EI. The EI of MDR1 and MRP1 (or nuclear MRP1 was analyzed with Spearman's rank correlation analysis. Using multiple tumor tissue assays, the location of MRP1 in other tissues was checked by HIC. Luciferase reporter assays of MDR1 promoter was carried out to check the connection between MRP1 and MDR1 promoter. RESULTS: MRP1 downregulation led to a decreased MDR1 expression in MC3/5FU cells which was caused by decreased activity of MDR1 promoter. IHC study of 127 cases of MEC tissues demonstrated a strong positive correlation between nuclear MRP1 expression and MDR1 expression. Furthermore, IHC study of multiple tumor tissue array sections showed that although nuclear MRP1 widely existed in MEC tissues, it was not found in normal tissues or other tumor tissues. CONCLUSIONS: Our findings indicate that nuclear MRP1 contributes to MDR mainly through regulating MDR1 expression in MEC. And the unique location of MRP1 made it an available target in identifying MEC from other tumors.

  17. Phosphorylation of mouse immunity-related GTPase (IRG resistance proteins is an evasion strategy for virulent Toxoplasma gondii.

    Directory of Open Access Journals (Sweden)

    Tobias Steinfeldt

    Full Text Available Virulence of complex pathogens in mammals is generally determined by multiple components of the pathogen interacting with the functional complexity and multiple layering of the mammalian immune system. It is most unusual for the resistance of a mammalian host to be overcome by the defeat of a single defence mechanism. In this study we uncover and analyse just such a case at the molecular level, involving the widespread intracellular protozoan pathogen Toxoplasma gondii and one of its most important natural hosts, the house mouse (Mus musculus. Natural polymorphism in virulence of Eurasian T. gondii strains for mice has been correlated in genetic screens with the expression of polymorphic rhoptry kinases (ROP kinases secreted into the host cell during infection. We show that the molecular targets of the virulent allelic form of ROP18 kinase are members of a family of cellular GTPases, the interferon-inducible IRG (immunity-related GTPase proteins, known from earlier work to be essential resistance factors in mice against avirulent strains of T. gondii. Virulent T. gondii strain ROP18 kinase phosphorylates several mouse IRG proteins. We show that the parasite kinase phosphorylates host Irga6 at two threonines in the nucleotide-binding domain, biochemically inactivating the GTPase and inhibiting its accumulation and action at the T. gondii parasitophorous vacuole membrane. Our analysis identifies the conformationally active switch I region of the GTP-binding site as an Achilles' heel of the IRG protein pathogen-resistance mechanism. The polymorphism of ROP18 in natural T. gondii populations indicates the existence of a dynamic, rapidly evolving ecological relationship between parasite virulence factors and host resistance factors. This system should be unusually fruitful for analysis at both ecological and molecular levels since both T. gondii and the mouse are widespread and abundant in the wild and are well-established model species with

  18. Increased callose deposition in plants lacking DYNAMIN-RELATED PROTEIN 2B is dependent upon POWDERY MILDEW RESISTANT 4.

    Science.gov (United States)

    Leslie, Michelle E; Rogers, Sean W; Heese, Antje

    2016-11-01

    Callose deposition within the cell wall is a well-documented plant immune response to pathogenic organisms as well as to pathogen-/microbe- associated molecular patterns (P/MAMPs). However, the molecular mechanisms that modulate pathogen-induced callose deposition are less understood. We reported previously that Arabidopsis plants lacking the vesicle trafficking component DYNAMIN-RELATED PROTEIN 2B (DRP2B) display increased callose deposition in response to the PAMP flg22. Here, we show that increased number of flg22-induced callose deposits in drp2b leaves is fully dependent on the callose synthase POWDERY MILDEW RESISTANT 4 (PMR4). We propose that in addition to functioning in flg22-induced endocytosis of the plant receptor, FLAGELLIN SENSING 2, DRP2B may regulate the trafficking of proteins involved in callose synthesis, such as PMR4, and/or callose degradation.

  19. RNA expression of breast cancer resistance protein, lung resistance-related protein, multidrug resistance-associated proteins 1 and 2, and multidrug resistance gene 1 in breast cancer: correlation with chemotherapeutic response

    NARCIS (Netherlands)

    H. Burger (Herman); J.A. Foekens (John); M.P. Look (Maxime); M.E. Meijer van Gelder (Marion); J.G.M. Klijn (Jan); E.A.C. Wiemer (Erik); G. Stoter (Gerrit); K. Nooter (Kees)

    2003-01-01

    textabstractPURPOSE: The aim of this study was to investigate whether expression of particular drug resistance genes in primary operable breast cancer correlates with response to first-line chemotherapy in advanced disease. EXPERIMENTAL DESIGN: We determined mRNA levels of BCRP,

  20. Moss Pathogenesis-Related-10 Protein Enhances Resistance to Pythium irregulare in Physcomitrella patens and Arabidopsis thaliana.

    Science.gov (United States)

    Castro, Alexandra; Vidal, Sabina; Ponce de León, Inés

    2016-01-01

    Plants respond to pathogen infection by activating signaling pathways leading to the accumulation of proteins with diverse roles in defense. Here, we addressed the functional role of PpPR-10, a pathogenesis-related (PR)-10 gene, of the moss Physcomitrella patens, in response to biotic stress. PpPR-10 belongs to a multigene family and encodes a protein twice the usual size of PR-10 proteins due to the presence of two Bet v1 domains. Moss PR-10 genes are differentially regulated during development and inoculation with the fungal pathogen Botrytis cinerea. Specifically, PpPR-10 transcript levels increase significantly by treatments with elicitors of Pectobacterium carotovorum subsp. carotovorum, spores of B. cinerea, and the defense hormone salicylic acid. To characterize the role of PpPR-10 in plant defense against pathogens, we conducted overexpression analysis in P. patens and in Arabidopsis thaliana. We demonstrate that constitutive expression of PpPR-10 in moss tissues increased resistance against the oomycete Pythium irregulare. PpPR-10 overexpressing moss plants developed less symptoms and decreased mycelium growth than wild type plants. In addition, PpPR-10 overexpressing plants constitutively produced cell wall depositions in protonemal tissue. Ectopic expression of PpPR-10 in Arabidopsis resulted in increased resistance against P. irregulare as well, evidenced by smaller lesions and less cellular damage compared to wild type plants. These results indicate that PpPR-10 is functionally active in the defense against the pathogen P. irregulare, in both P. patens and Arabidopsis, two evolutionary distant plants. Thus, P. patens can serve as an interesting source of genes to improve resistance against pathogen infection in flowering plants.

  1. Moss Pathogenesis-Related-10 protein enhances resistance to Pythium irregulare in Physcomitrella patens and Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Alexandra eCastro

    2016-04-01

    Full Text Available Plants respond to pathogen infection by activating signaling pathways leading to the accumulation of proteins with diverse roles in defense. Here, we addressed the functional role of PpPR-10, a pathogenesis-related (PR-10 gene, of the moss Physcomitrella patens, in response to biotic stress. PpPR-10 belongs to a multigene family and encodes a protein twice the usual size of PR-10 proteins due to the presence of two Bet v1 domains. Moss PR-10 genes are differentially regulated during development and inoculation with the fungal pathogen Botrytis cinerea. Specifically, PpPR-10 transcript levels increase significantly by treatments with elicitors of Pectobacterium carotovorum subsp. carotovorum, spores of B. cinerea, and the defense hormone salicylic acid. To characterize the role of PpPR-10 in plant defense against pathogens, we conducted overexpression analysis in P. patens and in Arabidopsis thaliana. We demonstrate that constitutive expression of PpPR-10 in moss tissues increased resistance against the oomycete Pythium irregulare. PpPR-10 overexpressing moss plants developed less symptoms and decreased mycelium growth than wild type plants. In addition, PpPR-10 overexpressing plants constitutively produced cell wall depositions in protonemal tissue. Ectopic expression of PpPR-10 in Arabidopsis resulted in increased resistance against P. irregulare as well, evidenced by smaller lesions and less cellular damage compared to wild type plants. These results indicate that PpPR-10 is functionally active in the defense against the pathogen P. irregulare, in both P. patens and Arabidopsis, two evolutionary distant plants. Thus, P. patens can serve as an interesting source of genes to improve resistance against pathogen infection in flowering plants.

  2. Retinol-Binding Protein 4 and Its Relation to Insulin Resistance in Obese Children before and after Weight Loss

    OpenAIRE

    Reinehr, Thomas; Stoffel-Wagner, Birgit; Roth, Christian L.

    2008-01-01

    Context: There are limited and controversial data concerning the relationships between retinol-binding protein 4 (RBP4), weight status, and insulin resistance in obese humans and especially in children.

  3. Overexpression of a stress-responsive U-box protein gene VaPUB affects the accumulation of resistance related proteins in Vitis vinifera 'Thompson Seedless'.

    Science.gov (United States)

    Jiao, Li; Zhang, Yali; Lu, Jiang

    2017-03-01

    Many U-box proteins have been identified and characterized as important factors against environmental stresses such as chilling, heat, salinity and pathogen attack in plant. Our previous research reported the cloning of a novel U-box protein gene VaPUB from Vitis amurensis 'Zuoshanyi' grape and suggested a function of it in related to cold stress in the model plant Arabidopsis system. In this study, the role of VaPUB in response to biotic and abiotic stress was further analyzed in the homologous grapevine system by studying the transcript regulation and the protein accumulation in VaPUB transgenic vines. The expression analysis assay shown that VaPUB was significantly up-regulated 6 h after cold treatment and as early as 2 h post inoculation with Plasmopara viticola, a pathogen causing downy mildew disease in grapevine. Over-expressing VaPUB in V. Vinifera 'Thompson Seedless' affected the microstructure of leaves. The proteome assay shown that the accumulation of pathogenesis-related protein PR10 and many proteins involved in carbon and energy metabolism, oxidation reaction and protein metabolism were significantly altered in transgenic vines. In comparison with wild type plants, the expression level of PR10 family genes was significantly decreased in VaPUB transgenic vines under P. viticola treatment or cold stress. Results from this study showed that the U-box protein gene PUB quickly responded to both biotic stress and abiotic stress and significantly influenced the accumulation of resistance related proteins in grapevine. Copyright © 2016. Published by Elsevier Masson SAS.

  4. Low-Density Lipoprotein Receptor-Related Protein-1 Protects Against Hepatic Insulin Resistance and Hepatic Steatosis

    Directory of Open Access Journals (Sweden)

    Yinyuan Ding

    2016-05-01

    Full Text Available Low-density lipoprotein receptor-related protein-1 (LRP1 is a multifunctional uptake receptor for chylomicron remnants in the liver. In vascular smooth muscle cells LRP1 controls reverse cholesterol transport through platelet-derived growth factor receptor β (PDGFR-β trafficking and tyrosine kinase activity. Here we show that LRP1 regulates hepatic energy homeostasis by integrating insulin signaling with lipid uptake and secretion. Somatic inactivation of LRP1 in the liver (hLRP1KO predisposes to diet-induced insulin resistance with dyslipidemia and non-alcoholic hepatic steatosis. On a high-fat diet, hLRP1KO mice develop a severe Metabolic Syndrome secondary to hepatic insulin resistance, reduced expression of insulin receptors on the hepatocyte surface and decreased glucose transporter 2 (GLUT2 translocation. While LRP1 is also required for efficient cell surface insulin receptor expression in the absence of exogenous lipids, this latent state of insulin resistance is unmasked by exposure to fatty acids. This further impairs insulin receptor trafficking and results in increased hepatic lipogenesis, impaired fatty acid oxidation and reduced very low density lipoprotein (VLDL triglyceride secretion.

  5. Multidrug resistance associated proteins in multidrug resistance

    OpenAIRE

    Sodani, Kamlesh; Patel, Atish; Kathawala, Rishil J.; Chen, Zhe-Sheng

    2012-01-01

    Multidrug resistance proteins (MRPs) are members of the C family of a group of proteins named ATP-binding cassette (ABC) transporters. These ABC transporters together form the largest branch of proteins within the human body. The MRP family comprises of 13 members, of which MRP1 to MRP9 are the major transporters indicated to cause multidrug resistance in tumor cells by extruding anticancer drugs out of the cell. They are mainly lipophilic anionic transporters and are reported to transport fr...

  6. Proteomic and biochemical assays of glutathione-related proteins in susceptible and multiple herbicide resistant Avena fatua L.

    Science.gov (United States)

    Burns, Erin E; Keith, Barbara K; Refai, Mohammed Y; Bothner, Brian; Dyer, William E

    2017-08-01

    Extensive herbicide usage has led to the evolution of resistant weed populations that cause substantial crop yield losses and increase production costs. The multiple herbicide resistant (MHR) Avena fatua L. populations utilized in this study are resistant to members of all selective herbicide families, across five modes of action, available for A. fatua control in U.S. small grain production, and thus pose significant agronomic and economic threats. Resistance to ALS and ACCase inhibitors is not conferred by target site mutations, indicating that non-target site resistance mechanisms are involved. To investigate the potential involvement of glutathione-related enzymes in the MHR phenotype, we used a combination of proteomic, biochemical, and immunological approaches to compare their constitutive activities in herbicide susceptible (HS1 and HS2) and MHR (MHR3 and MHR4) A. fatua plants. Proteomic analysis identified three tau and one phi glutathione S-transferases (GSTs) present at higher levels in MHR compared to HS plants, while immunoassays revealed elevated levels of lambda, phi, and tau GSTs. GST specific activity towards 1-chloro-2,4-dinitrobenzene was 1.2-fold higher in MHR4 than in HS1 plants and 1.3- and 1.2-fold higher in MHR3 than in HS1 and HS2 plants, respectively. However, GST specific activities towards fenoxaprop-P-ethyl and imazamethabenz-methyl were not different between untreated MHR and HS plants. Dehydroascorbate reductase specific activity was 1.4-fold higher in MHR than HS plants. Pretreatment with the GST inhibitor NBD-Cl did not affect MHR sensitivity to fenoxaprop-P-ethyl application, while the herbicide safener and GST inducer mefenpyr reduced the efficacy of low doses of fenoxaprop-P-ethyl on MHR4 but not MHR3 plants. Mefenpyr treatment also partially reduced the efficacy of thiencarbazone-methyl or mesosulfuron-methyl on MHR3 or MHR4 plants, respectively. Overall, the GSTs described here are not directly involved in enhanced rates of

  7. Defects in mitochondrial fission protein dynamin-related protein 1 are linked to apoptotic resistance and autophagy in a lung cancer model.

    Directory of Open Access Journals (Sweden)

    Kelly Jean Thomas

    Full Text Available Evasion of apoptosis is implicated in almost all aspects of cancer progression, as well as treatment resistance. In this study, resistance to apoptosis was identified in tumorigenic lung epithelial (A549 cells as a consequence of defects in mitochondrial and autophagic function. Mitochondrial function is determined in part by mitochondrial morphology, a process regulated by mitochondrial dynamics whereby the joining of two mitochondria, fusion, inhibits apoptosis while fission, the division of a mitochondrion, initiates apoptosis. Mitochondrial morphology of A549 cells displayed an elongated phenotype-mimicking cells deficient in mitochondrial fission protein, Dynamin-related protein 1 (Drp1. A549 cells had impaired Drp1 mitochondrial recruitment and decreased Drp1-dependent fission. Cytochrome c release and caspase-3 and PARP cleavage were impaired both basally and with apoptotic stimuli in A549 cells. Increased mitochondrial mass was observed in A549 cells, suggesting defects in mitophagy (mitochondrial selective autophagy. A549 cells had decreased LC3-II lipidation and lysosomal inhibition suggesting defects in autophagy occur upstream of lysosomal degradation. Immunostaining indicated mitochondrial localized LC3 punctae in A549 cells increased after mitochondrial uncoupling or with a combination of mitochondrial depolarization and ectopic Drp1 expression. Increased inhibition of apoptosis in A549 cells is correlated with impeded mitochondrial fission and mitophagy. We suggest mitochondrial fission defects contribute to apoptotic resistance in A549 cells.

  8. Resistance training-induced changes in integrated myofibrillar protein synthesis are related to hypertrophy only after attenuation of muscle damage.

    Science.gov (United States)

    Damas, Felipe; Phillips, Stuart M; Libardi, Cleiton A; Vechin, Felipe C; Lixandrão, Manoel E; Jannig, Paulo R; Costa, Luiz A R; Bacurau, Aline V; Snijders, Tim; Parise, Gianni; Tricoli, Valmor; Roschel, Hamilton; Ugrinowitsch, Carlos

    2016-09-15

    Skeletal muscle hypertrophy is one of the main outcomes from resistance training (RT), but how it is modulated throughout training is still unknown. We show that changes in myofibrillar protein synthesis (MyoPS) after an initial resistance exercise (RE) bout in the first week of RT (T1) were greater than those seen post-RE at the third (T2) and tenth week (T3) of RT, with values being similar at T2 and T3. Muscle damage (Z-band streaming) was the highest during post-RE recovery at T1, lower at T2 and minimal at T3. When muscle damage was the highest, so was the integrated MyoPS (at T1), but neither were related to hypertrophy; however, integrated MyoPS at T2 and T3 were correlated with hypertrophy. We conclude that muscle hypertrophy is the result of accumulated intermittent increases in MyoPS mainly after a progressive attenuation of muscle damage. Skeletal muscle hypertrophy is one of the main outcomes of resistance training (RT), but how hypertrophy is modulated and the mechanisms regulating it are still unknown. To investigate how muscle hypertrophy is modulated through RT, we measured day-to-day integrated myofibrillar protein synthesis (MyoPS) using deuterium oxide and assessed muscle damage at the beginning (T1), at 3 weeks (T2) and at 10 weeks of RT (T3). Ten young men (27 (1) years, mean (SEM)) had muscle biopsies (vastus lateralis) taken to measure integrated MyoPS and muscle damage (Z-band streaming and indirect parameters) before, and 24 h and 48 h post resistance exercise (post-RE) at T1, T2 and T3. Fibre cross-sectional area (fCSA) was evaluated using biopsies at T1, T2 and T3. Increases in fCSA were observed only at T3 (P = 0.017). Changes in MyoPS post-RE at T1, T2 and T3 were greater at T1 (P Muscle damage was the highest during post-RE recovery at T1, attenuated at T2 and further attenuated at T3. The change in MyoPS post-RE at both T2 and T3, but not at T1, was strongly correlated (r ≈ 0.9, P muscle hypertrophy. Initial Myo

  9. Constitutive expression of pathogenesis-related proteins and antioxydant enzyme activities triggers maize resistance towards Fusarium verticillioides.

    Science.gov (United States)

    Maschietto, Valentina; Lanubile, Alessandra; Leonardis, Silvana De; Marocco, Adriano; Paciolla, Costantino

    2016-08-01

    Fusarium verticillioides is a fungal pathogen of maize that causes ear rot and contaminates the grains with fumonisin mycotoxins. Breeding for resistance to Fusarium emerged as the most economic and environmentally safe strategy; therefore the discovery of resistant sources and effective molecular markers are a priority. Ears of resistant (CO441 and CO433) and susceptible (CO354 and CO389) maize lines were inoculated with F. verticillioides and the expression of pathogenesis-related (PR) genes (PR1, PR5, PRm3, PRm6) and genes that protect from oxidative stress (peroxidase, catalase, superoxide dismutase and ascorbate peroxidase) were evaluated in the kernels at 72h post inoculation. In addition, the oxidation level and the enzymatic activity of ascorbate-glutathione cycle, catalase, superoxide dismutase and cytosolic and wall peroxidases were investigated. The uninoculated kernels of the resistant lines showed higher gene expression and enzymatic activities, highlighting the key role of constitutive resistance in limiting pathogen attack. In contrast, the susceptible lines activated defensive genes only after pathogen inoculation, resulting in increased levels of H2O2 and lipid peroxidation, as well as lower enzymatic activities. The constitutive defenses observed in this study from seed could be profitably exploited to develop markers to speed up conventional breeding programs in the selection of resistant genotypes. Copyright © 2016 Elsevier GmbH. All rights reserved.

  10. C1q/TNF-related protein 6 (CTRP6) links obesity to adipose tissue inflammation and insulin resistance.

    Science.gov (United States)

    Lei, Xia; Seldin, Marcus M; Little, Hannah C; Choy, Nicholas; Klonisch, Thomas; Wong, G William

    2017-09-08

    Obesity is associated with chronic low-grade inflammation, and metabolic regulators linking obesity to inflammation have therefore received much attention. Secreted C1q/TNF-related proteins (CTRPs) are one such group of regulators that regulate glucose and fat metabolism in peripheral tissues and modulate inflammation in adipose tissue. We have previously shown that expression of CTRP6 is up-regulated in leptin-deficient mice and, conversely, down-regulated by the anti-diabetic drug rosiglitazone. Here, we provide evidence for a novel role of CTRP6 in modulating both inflammation and insulin sensitivity. We found that in obese and diabetic humans and mouse models, CTRP6 expression was markedly up-regulated in adipose tissue and that stromal vascular cells, such as macrophages, are a major CTRP6 source. Overexpressing mouse or human CTRP6 impaired glucose disposal in peripheral tissues in response to glucose and insulin challenge in wild-type mice. Conversely, Ctrp6 gene deletion improved insulin action and increased metabolic rate and energy expenditure in diet-induced obese mice. Mechanistically, CTRP6 regulates local inflammation and glucose metabolism by targeting macrophages and adipocytes, respectively. In cultured macrophages, recombinant CTRP6 dose-dependently up-regulated the expression and production of TNF-α. Conversely, CTRP6 deficiency reduced circulating inflammatory cytokines and pro-inflammatory macrophages in adipose tissue. CTRP6-overexpressing mice or CTRP6-treated adipocytes had reduced insulin-stimulated Akt phosphorylation and glucose uptake. In contrast, loss of CTRP6 enhanced insulin-stimulated Akt activation in adipose tissue. Together, these results establish CTRP6 as a novel metabolic/immune regulator linking obesity to adipose tissue inflammation and insulin resistance. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Effect of acute endurance and resistance exercise on endocrine hormones directly related to lipolysis and skeletal muscle protein synthesis in adult individuals with obesity.

    Science.gov (United States)

    Hansen, Dominique; Meeusen, Romain; Mullens, Annelies; Dendale, Paul

    2012-05-01

    In subjects with obesity, the implementation of long-term exercise intervention increases lean tissue mass and lowers adipose tissue mass. However, data indicate a blunted lipolytic response, and/or skeletal muscle protein synthesis, when subjects with obesity are exposed to acute endurance or resistance exercise, respectively. Therefore, subjects with obesity seem to display a suboptimal physiological response to acute exercise stimuli. It might be hypothesized that hormonal disturbances contribute, at least in part, to these abnormal physiological reactions in the obese. This review discusses the impact of acute endurance and resistance exercise on endocrine hormones directly related to lipolysis and/or skeletal muscle protein synthesis (insulin, [nor]epinephrine, cortisol, growth hormone, testosterone, triiodothyronine, atrial natriuretic peptide, insulin-like growth factor-1), as well as the impact of long-term endurance and resistance exercise intervention on these hormonal responses to acute endurance and resistance exercise. In the obese, some endocrinological disturbances during acute endurance and resistance exercise have been identified: a blunted blood growth hormone, atrial natriuretic peptide and epinephrine release, and greater cortisol and insulin release. These hormonal disturbances might contribute to a suppressed lipolytic response, and/or suppressed skeletal muscle protein synthesis, as a result of acute endurance or resistance exercise, respectively. In subjects with obesity, the impact of acute endurance and resistance exercise on other endocrine hormones (norepinephrine, testosterone, triiodothyronine, insulin-like growth factor-1) remains elusive. Furthermore, whether long-term endurance and resistance exercise intervention might reverse these hormonal disturbances during acute endurance and resistance exercise in these individuals remains unknown.

  12. Breast Cancer Resistance Protein Expression and 5-Fluorouracil Resistance

    Institute of Scientific and Technical Information of China (English)

    JIAN-HUI YUAN; ZHI-XIONG ZHUANG; JIN-QUAN CHENG; LONG-YUAN JIANG; WEI-DONG JI; LIANG-FENG GUO; JIAN-JUN LIU; XING-YUN XU; JING-SONG HE; XIAN-MING WANG

    2008-01-01

    To filtrate breast cancer resistance protein (BCRP)-mediated resistant agents and to investigate clinical relationship between BCRP expression and drug resistance. Methods MTT assay was performed to filtrate BCRP-mediated resistant agents with BCRP expression cell model and to detect chemosensitivity of breast cancer tissue specimens to these agents. A high performance liquid chromatography (HPLC) assay was established, and was used to measure the relative dose of intracellular retention resistant agents. RT-PCR and immununohistochemistry (IHC) were employed to investigate the BCRP expression in breast cancer tissue specimens. Results MTT assay showed that the expression of BCRP increased with the increasing resistance of 5-fluorouracil (5-Fu) (P=0.8124, P<0.01). Condusion Resistance to 5-Fu can be mediated by BCRP. Clinical chemotherapy for breast cancer patients can be optimized based on BCRP-positive expression.

  13. Mutation of G234 amino acid residue in Candida albicans drug-resistance-related protein Rta2p is associated with fluconazole resistance and dihydrosphingosine transport

    Science.gov (United States)

    Zhang, Shi-Qun; Miao, Qi; Li, Li-Ping; Zhang, Lu-lu; Yan, Lan; Jia, Yu; Cao, Yong-Bing; Jiang, Yuan-Ying

    2015-01-01

    Widespread and repeated use of azoles has led to the rapid development of drug resistance in Candida albicans. Our previous study found Rta2p, a membrane protein with 7 transmembrane domains, was involved in calcineurin-mediated azole resistance and sphingoid long-chain base release in C. albicans. Conserved amino acids in the transmembrane domain of Rta2p were subjected to site-directed mutagenesis. The sensitivity of C. albicans to fluconazole in vitro was examined by minimum inhibitory concentration and killing assay, and the therapeutic efficacy of fluconazole in vivo was performed by systemic mice candidiasis model. Furthermore, dihydrosphingosine transport activity was detected by NBD labeled D-erythro-dihydrosphingosine uptake and release assay, and the sensitivity to sphingolipid biosynthesis inhibitors. We successfully constructed 14 mutant strains of Rta2p, screened them by minimum inhibitory concentration and found Ca2+ did not completely induce fluconazole resistance with G158E and G234S mutations. Furthermore, we confirmed that G234S mutant enhanced the therapeutic efficacy of fluconazole against systemic candidiasis and significantly increased the accumulation of dihydrosphingosine by decreasing its release. However, G158E mutant didn't affect drug therapeutic efficacy in vivo and dihydrosphingosine transport in C. albicans. G234 of Rta2p in C. albicans is crucial in calcineurin-mediated fluconazole resistance and dihydrosphingosine transport. PMID:26220356

  14. Mutation of G234 amino acid residue in candida albicans drug-resistance-related protein Rta2p is associated with fluconazole resistance and dihydrosphingosine transport.

    Science.gov (United States)

    Zhang, Shi-Qun; Miao, Qi; Li, Li-Ping; Zhang, Lu-Lu; Yan, Lan; Jia, Yu; Cao, Yong-Bing; Jiang, Yuan-Ying

    2015-01-01

    Widespread and repeated use of azoles has led to the rapid development of drug resistance in Candida albicans. Our previous study found Rta2p, a membrane protein with 7 transmembrane domains, was involved in calcineurin-mediated azole resistance and sphingoid long-chain base release in C. albicans. Conserved amino acids in the transmembrane domain of Rta2p were subjected to site-directed mutagenesis. The sensitivity of C. albicans to fluconazole in vitro was examined by minimum inhibitory concentration and killing assay, and the therapeutic efficacy of fluconazole in vivo was performed by systemic mice candidiasis model. Furthermore, dihydrosphingosine transport activity was detected by NBD labeled D-erythro-dihydrosphingosine uptake and release assay, and the sensitivity to sphingolipid biosynthesis inhibitors. We successfully constructed 14 mutant strains of Rta2p, screened them by minimum inhibitory concentration and found Ca(2+) did not completely induce fluconazole resistance with G158E and G234S mutations. Furthermore, we confirmed that G234S mutant enhanced the therapeutic efficacy of fluconazole against systemic candidiasis and significantly increased the accumulation of dihydrosphingosine by decreasing its release. However, G158E mutant didn't affect drug therapeutic efficacy in vivo and dihydrosphingosine transport in C. albicans. G234 of Rta2p in C. albicans is crucial in calcineurin-mediated fluconazole resistance and dihydrosphingosine transport.

  15. Multidrug resistance associated proteins in multidrug resistance

    Institute of Scientific and Technical Information of China (English)

    Kamlesh Sodani; Atish Patel; Rishil J. Kathawala; Zhe-Sheng Chen

    2012-01-01

    Multidrug resistance proteins (MRPs) are members of the C family of a group of proteins named ATP-binding cassette (ABC) transporters.These ABC transporters together form the largest branch of proteins within the human body.The MRP family comprises of 13 members,of which MRP1 to MRP9 are the major transporters indicated to cause multidrug resistance in tumor cells by extruding anticancer drugs out of the cell.They are mainly lipophilic anionic transporters and are reported to transport free or conjugates of glutathione (GSH),glucuronate,or sulphate.In addition,MRP1 to MRP3 can transport neutral organic drugs in free form in the presence of free GSH.Collectively,MRPs can transport drugs that differ structurally and mechanistically,including natural anticancer drugs,nucleoside analogs,antimetabolites,and tyrosine kinase inhibitors.Many of these MRPs transport physiologically important anions such as leukotriene C4,bilirubin glucuronide,and cyclic nucleotides.This review focuses mainly on the physiological functions,cellular resistance characteristics,and probable in vivo role of MRP1 to MRP9.

  16. Emergence of clonally related multidrug resistant Haemophilus influenzae with penicillin-binding protein 3-mediated resistance to extended-spectrum cephalosporins, Norway, 2006 to 2013.

    Science.gov (United States)

    Skaare, D; Anthonisen, I L; Kahlmeter, G; Matuschek, E; Natås, O B; Steinbakk, M; Sundsfjord, A; Kristiansen, B E

    2014-12-11

    Resistance to cephalosporins in Haemophilus influenzae is usually caused by characteristic alterations in penicillin-binding protein 3 (PBP3), encoded by the ftsI gene. Resistance to extended-spectrum cephalosporins is associated with high-level PBP3-mediated resistance (high-rPBP3), defined by the second stage S385T substitution in addition to a first stage substitution (R517H or N526K). The third stage L389F substitution is present in some high-rPBP3 strains. High-rPBP3 H. influenzae are considered rare outside Japan and Korea. In this study, 30 high-rPBP3 isolates from Norway, collected between 2006 and 2013, were examined by serotyping, multilocus sequence typing (MLST), ftsI sequencing, detection of beta-lactamase genes and minimum inhibitory concentration (MIC) determination. MICs were interpreted according to clinical breakpoints from the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Respiratory isolates predominated (proportion: 24/30). The 30 isolates included one serotype f isolate, while the remaining 29 lacked polysaccharide capsule genes. Resistance to extended-spectrum cephalosporins (cefixime, 29 isolates/30 isolates; cefepime, 28/30; cefotaxime, 26 /30; ceftaroline, 26/30; ceftriaxone, 14/30), beta-lactamase production (11/30) and co-resistance to non-beta-lactams (trimethoprim-sulfamethoxazole, 13/30; tetracycline, 4/30; chloramphenicol, 4/30; ciprofloxacin, 3/30) was frequent. The N526K substitution in PBP3 was present in 23 of 30 isolates; these included a blood isolate which represents the first invasive S385T + N526K isolate reported from Europe. The L389F substitution, present in 16 of 30 isolates, coincided with higher beta-lactam MICs. Non-susceptibility to meropenem was frequent in S385T + L389F + N526K isolates (8/12). All 11 beta-lactamase positive isolates were TEM-1. Five clonal groups of two to 10 isolates with identical MLST-ftsI allelic profiles were observed, including the first reported high-rPBP3

  17. Dietary soy protein improves adipose tissue dysfunction by modulating parameters related with oxidative stress in dyslipidemic insulin-resistant rats.

    Science.gov (United States)

    Illesca, Paola G; Álvarez, Silvina M; Selenscig, Dante A; Ferreira, María Del R; Giménez, María S; Lombardo, Yolanda B; D'Alessandro, María E

    2017-04-01

    The present study investigates the benefits of the dietary intake of soy protein on adipose tissue dysfunction in a rat model that mimics several aspects of the human metabolic syndrome. Wistar rats were fed a sucrose-rich diet (SRD) for 4 months. After that, half of the animals continued with SRD until month 8 while in the other half, casein protein was replaced by isolated soy protein for 4 months (SRD-S). A reference group consumed a control diet all the time. In adipose tissue we determined: i) the activities of antioxidant enzymes, gene expression of Mn-superoxide dismutase (SOD) and glutathione peroxidase (GPx), and glutathione redox state ii) the activity of xanthine oxidase (XO), ROS levels and the gene expression of NAD(P)H oxidase iii) the expression of the nuclear factor erythroid-2 related factor-2 (Nrf2). Besides, adiposity visceral index, insulin sensitivity, and tumor necrosis factor-α (TNF-α) in plasma were determined. Compared with the SRD-fed rats, the animals fed a SRD-S showed: activity normalization of SOD and glutathione reductase, improvement of mRNA SOD and normalization of mRNA GPx without changes in the expression of the Nrf2, and improvement of glutathione redox state. These results were accompanied by a normalization of XO activity and improvement of both the ROS production as well as TNF-α levels in plasma. Besides, adipocyte size distribution, adiposity visceral index and insulin sensitivity improved. The results suggest that soy protein can be a complementary nutrient for treating some signs of the metabolic syndrome. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  18. Targeting AMP-activated protein kinase in adipocytes to modulate obesity-related adipokine production associated with insulin resistance and breast cancer cell proliferation

    Directory of Open Access Journals (Sweden)

    Grisouard Jean

    2011-07-01

    Full Text Available Abstract Background Adipokines, e.g. TNFα, IL-6 and leptin increase insulin resistance, and consequent hyperinsulinaemia influences breast cancer progression. Beside its mitogenic effects, insulin may influence adipokine production from adipocyte stromal cells and paracrine enhancement of breast cancer cell growth. In contrast, adiponectin, another adipokine is protective against breast cancer cell proliferation and insulin resistance. AMP-activated protein kinase (AMPK activity has been found decreased in visceral adipose tissue of insulin-resistant patients. Lipopolysaccharides (LPS link systemic inflammation to high fat diet-induced insulin resistance. Modulation of LPS-induced adipokine production by metformin and AMPK activation might represent an alternative way to treat both, insulin resistance and breast cancer. Methods Human preadipocytes obtained from surgical biopsies were expanded and differentiated in vitro into adipocytes, and incubated with siRNA targeting AMPKalpha1 (72 h, LPS (24 h, 100 μg/ml and/or metformin (24 h, 1 mM followed by mRNA extraction and analyses. Additionally, the supernatant of preadipocytes or derived-adipocytes in culture for 24 h was used as conditioned media to evaluate MCF-7 breast cancer cell proliferation. Results Conditioned media from preadipocyte-derived adipocytes, but not from undifferentiated preadipocytes, increased MCF-7 cell proliferation (p Conclusions Adipocyte-secreted factors enhance breast cancer cell proliferation, while AMPK and metformin improve the LPS-induced adipokine imbalance. Possibly, AMPK activation may provide a new way not only to improve the obesity-related adipokine profile and insulin resistance, but also to prevent obesity-related breast cancer development and progression.

  19. Diversity in fosfomycin resistance proteins

    Directory of Open Access Journals (Sweden)

    Matthew K. Thompson

    2015-03-01

    Full Text Available Certain strains of the soil microorganism Streptomyces produce an antibiotic, fosfomycin [(1 R,2 S-epoxypropylphosphonic acid], which is effective against both Gram-positive and Gram-negative pathogens by inhibiting the first committed step in cell-wall biosynthesis. Fosfomycin resistance proteins are metallo-enzymes that are known to inactivate the antibiotic by the addition of nucleophiles such as water, glutathione (GSH, l-cysteine and bacillithiol (BSH to the oxirane ring of the molecule. Progress in the characterisation of FosB-type fosfomycin resistance proteins found in many Gram-positive organisms has been slow. This paper provides a brief description of the diversity of fosfomycin resistance proteins in general and, more specifically, new data characterising the substrate selectivity, structure, mechanism and metal-ion dependence of FosB enzymes from pathogenic strains of Staphylococcus and Bacillus. These new findings include the high-resolution X-ray diffraction structures of FosB enzymes from Staphylococcus aureus and Bacillus cereus in various liganded states and kinetic data that suggest that Mn(II and BSH are the preferred divalent cation and thiol substrate for the reaction, respectively. The discovery of the inhibition of the enzyme by Zn(II led to the determination of a ternary structure of the FosB·Zn(II·fosfomycin·l-Cys complex which reveals both substrates present in a pose prior to reaction.

  20. Resisting protein adsorption on biodegradable polyester brushes.

    Science.gov (United States)

    Hu, Xinfang; Gorman, Christopher B

    2014-08-01

    The protein adsorption and degradation behaviors of poly(lactic acid), poly(glycolic acid) (PGA) and poly(ε-caprolactone) (PCL) brushes and their co-polymer brushes with oligo(ethylene glycol) (OEG) were studied. Both brush structure and relative amount of OEG and polyester were found to be important to the protein resistance of the brushes. A protein-resisting surface can be fabricated either by using OEG as the top layer of a copolymer brush or by increasing the amount of OEG relative to polyester when using a hydroxyl terminated OEG (OEG-OH) and a methoxy terminated OEG (OEG-OMe) mixture as the substrate layer. The degradation of single polyester brushes and their co-polymer brushes using OEG-OH as a substrate layer or using OEG as a top layer was hindered. This phenomenon was rationalized by the inhibition of the proposed back-biting process as the hydroxy end groups of polyester were blocked by OEG molecules. Among these brushes tested, PGA co-polymer brushes using the methoxy/hydroxyl OEG mixture as the substrate layer proved to be both protein-resistant and degradable due to the relatively large amount of OEG moieties and the good biodegradability of PGA.

  1. From resistance to relational inertia

    DEFF Research Database (Denmark)

    Scheuer, John Damm

    Empirical evidence have built up that shows that the concept of “resistance to change” does not fully explain the varied types of reactions found among recipients of organizational change initiatives. Instead of being only negative some change recipients reactions have been found to be positive...... processes and thus as social and relational rather than psychological phenomena. This have led some researchers to suggest that the definition of resistance to change have to be reformulated and others to suggest that the term “resistance to change” should either be reformulated in terms of sensemaking...... or improvisational organizing processes or be abandoned all together. This paper develops a view on difficulties related to organizational change processes that represents an alternative view to the “resistance- to- change” types of theorizing and other types of “barriers to change” views. Taking actor...

  2. Sucrose-mediated priming of plant defense responses and broad-spectrum disease resistance by overexpression of the maize pathogenesis-related PRms protein in rice plants.

    Science.gov (United States)

    Gómez-Ariza, Jorge; Campo, Sonia; Rufat, Mar; Estopà, Montserrat; Messeguer, Joaquima; San Segundo, Blanca; Coca, María

    2007-07-01

    Expression of pathogenesis-related (PR) genes is part of the plant's natural defense response against pathogen attack. The PRms gene encodes a fungal-inducible PR protein from maize. Here, we demonstrate that expression of PRms in transgenic rice confers broad-spectrum protection against pathogens, including fungal (Magnaporthe oryzae, Fusarium verticillioides, and Helminthosporium oryzae) and bacterial (Erwinia chrysanthemi) pathogens. The PRms-mediated disease resistance in rice plants is associated with an enhanced capacity to express and activate the natural plant defense mechanisms. Thus, PRms rice plants display a basal level of expression of endogenous defense genes in the absence of the pathogen. PRms plants also exhibit stronger and quicker defense responses during pathogen infection. We also have found that sucrose accumulates at higher levels in leaves of PRms plants. Sucrose responsiveness of rice defense genes correlates with the pathogen-responsive priming of their expression in PRms rice plants. Moreover, pretreatment of rice plants with sucrose enhances resistance to M. oryzae infection. Together, these results support a sucrose-mediated priming of defense responses in PRms rice plants which results in broad-spectrum disease resistance.

  3. Efflux kinetics and intracellular distribution of daunorubicin are not affected by major vault protein/lung resistance-related protein (vault) expression.

    NARCIS (Netherlands)

    Zon, van A; Mossink, MH; Schoester, M.; Scheper, R.J.; Sonneveld, P.; Wiemer, EA

    2004-01-01

    Vaults may contribute to multidrug resistance by transporting drugs away from their subcellular targets. To study the involvement of vaults in the extrusion of anthracyclines from the nucleus, we investigated the handling of daunorubicin by drug-sensitive and drug-resistant non-small lung cancer cel

  4. Glucocorticoids upregulates transepithelial electrical resistance and expression of tight junction-related protein in human trabecular meshwork cells

    Institute of Scientific and Technical Information of China (English)

    ZHUO Ye-hong; HUANG Ya-lin; WEI Yan-tao; LING Yun-lan; LIN Ming-kai; GE Jian

    2005-01-01

    @@ The trabecular meshwork is located at the anterior chamber angle, and is the main route for the outflow of aqueous humor. It is composed of perforated sheets of collagen and elastic tissue covered by trabecular meshwork (TM) cells, forming a filter with decreasing pore size as the canal of Schlemm is approached. TM cells have some endothelial properties, such as the presence of intercellular junctional complexes, particularly tight junctions (TJs). TJs form paracellular seals between adjacent cells and act as fences that segregate protein (and partially lipid) components of the apical and basolateral plasma membrane domains. Under the electron microscope, TJs appear as a series of discrete contacts between the lateral membranes of adjacent cells.

  5. Non-immune binding of human IgG to M-related proteins confers resistance to phagocytosis of group A streptococci in blood.

    Directory of Open Access Journals (Sweden)

    Harry S Courtney

    Full Text Available The non-immune binding of immunoglobulins by bacteria is thought to contribute to the pathogenesis of infections. M-related proteins (Mrp are group A streptococcal (GAS receptors for immunoglobulins, but it is not known if this binding has any impact on virulence. To further investigate the binding of immunoglobulins to Mrp, we engineered mutants of an M type 4 strain of GAS by inactivating the genes for mrp, emm, enn, sof, and sfbX and tested these mutants in IgG-binding assays. Inactivation of mrp dramatically decreased the binding of human IgG, whereas inactivation of emm, enn, sof, and sfbx had only minor effects, indicating that Mrp is a major IgG-binding protein. Binding of human immunoglobulins to a purified, recombinant form of Mrp indicated that it selectively binds to the Fc domain of human IgG, but not IgA or IgM and that it preferentially bound subclasses IgG₁>IgG₄>IgG₂>IgG₃. Recombinant proteins encompassing different regions of Mrp were engineered and used to map its IgG-binding domain to its A-repeat region and a recombinant protein with 3 A-repeats was a better inhibitor of IgG binding than one with a single A-repeat. A GAS mutant expressing Mrp with an in-frame deletion of DNA encoding the A-repeats had a dramatically reduced ability to bind human IgG and to grow in human blood. Mrp exhibited host specificity in binding IgG; human IgG was the best inhibitor of the binding of IgG followed by pig, horse, monkey, and rabbit IgG. IgG from goat, mouse, rat, cow, donkey, chicken, and guinea pig were poor inhibitors of binding. These findings indicate that Mrp preferentially binds human IgG and that this binding contributes to the ability of GAS to resist phagocytosis and may be a factor in the restriction of GAS infections to the human host.

  6. Relationship between PSII-D1-protein, xanthophyll cycle and the differences in capacities related to photodamage-resistance of indica and japonica subspecies of rice (O. sativa L.)

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@ To explore the mechanisms of the differences in capacities related to photodamage-resistance of indica and japonica subspecies, the xanthophyll cycle components, violaxanthin (V), antheraxanthin (A), zeaxanthin (Z), PSⅡ-D1-protein contents, and PSⅡ photochemical efficiency (Fv/Fm) were measured in rice leaves pretreated by streptomycin(SM, a PSⅡ-D1-protein inhibitor) and dithiothreitol (DTT, an xanthophyll cycle inhibitor), respectively.

  7. Effect of acute endurance and resistance exercise on endocrine hormones directly related to lipolysis and muscle protein synthesis in adult individuals with obesity: a review.

    OpenAIRE

    2012-01-01

    In subjects with obesity, the implementation of long-term exercise intervention increases lean tissue mass and lowers adipose tissue mass. However, data indicate a blunted lipolytic response, and/or skeletal muscle protein synthesis, when subjects with obesity are exposed to acute endurance or resistance exercise, respectively. Therefore, subjects with obesity seem to display a suboptimal physiological response to acute exercise stimuli. It might be hypothesized that hormonal disturb...

  8. Serum heat shock protein 27 antigen and antibody levels appear to be related to the macrovascular complications associated with insulin resistance: a pilot study.

    Science.gov (United States)

    Burut, Dayangku Fatiha Pengiran; Borai, Anwar; Livingstone, Callum; Ferns, Gordon

    2010-07-01

    Heat shock protein 27 (Hsp27) is over-expressed when cells are exposed to stressful conditions that include oxidative stress. Oxidative stress has been implicated in the pathogenesis of cardiovascular disease (CVD), diabetes and insulin resistance. We have investigated the concentrations of serum Hsp27 antigen and antibodies in subjects from different glycaemic categories, who either did or did not have established CVD. Serum Hsp27 antigen and antibody levels (immunoglobulins M and G (IgM and IgG)) were determined by enzyme-linked immunosorbent assays (ELISAs) in 68 individuals: 26 with normal glucose tolerance (NGT), 10 with (+) and 16 without (-) a history of CVD and 42 individuals with varying degrees of glucose intolerance (GI; 21 with and 21 without a history of CVD). Insulin sensitivity was determined in each subject using indices derived from the homeostasis model assessment of sensitivity and the insulin sensitivity index for glycaemia. Serum Hsp27 concentrations were significantly higher in GI (+CVD) subjects compared to GI (-CVD) subjects (p = 0.03), NGT (-CVD) subjects (p = 0.02) and NGT (+CVD) subjects (p = 0.04) and were positively correlated to fasting plasma glucose for all subjects (r = 0.28, p = 0.03). IgM antibody levels were significantly higher in GI (+CVD) subjects compared to NGT (-CVD) group (p = 0.02) and were inversely related to fasting insulin concentrations (r = -0.27, p = 0.04) and the 2-h insulin concentrations (r = -0.29, p = 0.03) for all subjects. Serum IgG antibody levels were higher in GI (+CVD) group compared to GI (-CVD) group (p = 0.06). In conclusion, Hsp27 and its antibody concentrations appear to relate to the presence of cardiovascular complications in patients with GI.

  9. DIRProt: a computational approach for discriminating insecticide resistant proteins from non-resistant proteins.

    Science.gov (United States)

    Meher, Prabina Kumar; Sahu, Tanmaya Kumar; Banchariya, Anjali; Rao, Atmakuri Ramakrishna

    2017-03-24

    Insecticide resistance is a major challenge for the control program of insect pests in the fields of crop protection, human and animal health etc. Resistance to different insecticides is conferred by the proteins encoded from certain class of genes of the insects. To distinguish the insecticide resistant proteins from non-resistant proteins, no computational tool is available till date. Thus, development of such a computational tool will be helpful in predicting the insecticide resistant proteins, which can be targeted for developing appropriate insecticides. Five different sets of feature viz., amino acid composition (AAC), di-peptide composition (DPC), pseudo amino acid composition (PAAC), composition-transition-distribution (CTD) and auto-correlation function (ACF) were used to map the protein sequences into numeric feature vectors. The encoded numeric vectors were then used as input in support vector machine (SVM) for classification of insecticide resistant and non-resistant proteins. Higher accuracies were obtained under RBF kernel than that of other kernels. Further, accuracies were observed to be higher for DPC feature set as compared to others. The proposed approach achieved an overall accuracy of >90% in discriminating resistant from non-resistant proteins. Further, the two classes of resistant proteins i.e., detoxification-based and target-based were discriminated from non-resistant proteins with >95% accuracy. Besides, >95% accuracy was also observed for discrimination of proteins involved in detoxification- and target-based resistance mechanisms. The proposed approach not only outperformed Blastp, PSI-Blast and Delta-Blast algorithms, but also achieved >92% accuracy while assessed using an independent dataset of 75 insecticide resistant proteins. This paper presents the first computational approach for discriminating the insecticide resistant proteins from non-resistant proteins. Based on the proposed approach, an online prediction server DIRProt has

  10. Drug efflux proteins in multidrug resistant bacteria

    NARCIS (Netherlands)

    vanVeen, HW; Konings, WN

    1997-01-01

    Bacteria contain an array of transport proteins in their cytoplasmic membrane. Many of these proteins play an important role in conferring resistance to toxic compounds. The multidrug efflux systems encountered in prokaryotic cells are very similar to those observed in eukaryotic cells. Therefore, a

  11. Drug efflux proteins in multidrug resistant bacteria

    NARCIS (Netherlands)

    vanVeen, HW; Konings, WN

    Bacteria contain an array of transport proteins in their cytoplasmic membrane. Many of these proteins play an important role in conferring resistance to toxic compounds. The multidrug efflux systems encountered in prokaryotic cells are very similar to those observed in eukaryotic cells. Therefore, a

  12. Yeast ABC proteins involved in multidrug resistance.

    Science.gov (United States)

    Piecuch, Agata; Obłąk, Ewa

    2014-03-01

    Pleiotropic drug resistance is a complex phenomenon that involves many proteins that together create a network. One of the common mechanisms of multidrug resistance in eukaryotic cells is the active efflux of a broad range of xenobiotics through ATP-binding cassette (ABC) transporters. Saccharomyces cerevisiae is often used as a model to study such activity because of the functional and structural similarities of its ABC transporters to mammalian ones. Numerous ABC transporters are found in humans and some are associated with the resistance of tumors to chemotherapeutics. Efflux pump modulators that change the activity of ABC proteins are the most promising candidate drugs to overcome such resistance. These modulators can be chemically synthesized or isolated from natural sources (e.g., plant alkaloids) and might also be used in the treatment of fungal infections. There are several generations of synthetic modulators that differ in specificity, toxicity and effectiveness, and are often used for other clinical effects.

  13. Age-related differences in the dose-response relationship of muscle protein synthesis to resistance exercise in young and old men.

    Science.gov (United States)

    Kumar, Vinod; Selby, Anna; Rankin, Debbie; Patel, Rekha; Atherton, Philip; Hildebrandt, Wulf; Williams, John; Smith, Kenneth; Seynnes, Olivier; Hiscock, Natalie; Rennie, Michael J

    2009-01-15

    We investigated how myofibrillar protein synthesis (MPS) and muscle anabolic signalling were affected by resistance exercise at 20-90% of 1 repetition maximum (1 RM) in two groups (25 each) of post-absorptive, healthy, young (24 +/- 6 years) and old (70 +/- 5 years) men with identical body mass indices (24 +/- 2 kg m(-2)). We hypothesized that, in response to exercise, anabolic signalling molecule phosphorylation and MPS would be modified in a dose-dependant fashion, but to a lesser extent in older men. Vastus lateralis muscle was sampled before, immediately after, and 1, 2 and 4 h post-exercise. MPS was measured by incorporation of [1,2-(13)C] leucine (gas chromatography-combustion-mass spectrometry using plasma [1,2-(13)C]alpha-ketoisocaparoate as surrogate precursor); the phosphorylation of p70 ribosomal S6 kinase (p70s6K) and eukaryotic initiation factor 4E binding protein 1 (4EBP1) was measured using Western analysis with anti-phosphoantibodies. In each group, there was a sigmoidal dose-response relationship between MPS at 1-2 h post-exercise and exercise intensity, which was blunted (P men. At all intensities, MPS fell in both groups to near-basal values by 2-4 h post-exercise. The phosphorylation of p70s6K and 4EBP1 at 60-90% 1 RM was blunted in older men. At 1 h post-exercise at 60-90% 1 RM, p70s6K phosphorylation predicted the rate of MPS at 1-2 h post-exercise in the young but not in the old. The results suggest that in the post-absorptive state: (i) MPS is dose dependant on intensity rising to a plateau at 60-90% 1 RM; (ii) older men show anabolic resistance of signalling and MPS to resistance exercise.

  14. Control of fire blight (Erwinia amylovora on apple trees with trunk-injected plant resistance inducers and antibiotics and assessment of induction of pathogenesis-related protein genes

    Directory of Open Access Journals (Sweden)

    Srđan G. Aćimović

    2015-02-01

    Full Text Available Management of fire blight is complicated by limitations on use of antibiotics in agriculture, antibiotic resistance development, and limited efficacy of alternative control agents. Even though successful in control, preventive antibiotic sprays also affect non-target bacteria, aiding the selection for resistance which could ultimately be transferred to the pathogen Erwinia amylovora. Trunk injection is a target-precise pesticide delivery method that utilizes tree xylem to distribute injected compounds. Trunk injection could decrease antibiotic usage in the open environment and increase the effectiveness of compounds in fire blight control. In field experiments, after 1-2 apple tree injections of either streptomycin, potassium phosphites (PH or acibenzolar-S-methyl (ASM, significant reduction of blossom and shoot blight symptoms was observed compared to water- or non-injected control trees. Overall disease suppression with streptomycin was lower than typically observed following spray applications to flowers. Trunk injection of oxytetracycline resulted in excellent control of shoot blight severity, suggesting that injection is a superior delivery method for this antibiotic. Injection of both ASM and PH resulted in the significant induction of PR-1, PR-2 and PR-8 protein genes in apple leaves indicating induction of systemic acquired resistance (SAR under field conditions. The time separating SAR induction and fire blight symptom suppression indicated that various defensive compounds within the SAR response were synthesized and accumulated in the canopy. ASM and PH suppressed fire blight even after cessation of induced gene expression. With the development of injectable formulations and optimization of doses and injection schedules, the injection of protective compounds could serve as an effective option for fire blight control.

  15. A ribonuclease-resistant region of 5S RNA and its relation to the RNA binding sites of proteins L18 and L25

    DEFF Research Database (Denmark)

    Douthwaite, S; Garrett, R A; Wagner, R

    1979-01-01

    An RNA fragment, constituting three subfragments of nucleotide sequences 1-11, 69-87 and 89-120, is the most ribonuclease-resistant part of the native 5S RNA of Escherichia coli, at 0 degrees C. A smaller fragment of nucleotide sequence 69-87 and 90-110 is ribonuclease-resistant at 25 degrees....... Degradation of the L25-5S RNA complex with ribonuclease A or T2 yielded RNA fragments similar to those of the free 5S RNA at 0 degrees C and 25 degrees C; moreover L25 remained strongly bound to both RNA fragments and also produced some opening of the RNA structure in at least two positions. Protein L18...... initially protected most of the 5S RNA against ribonuclease digestion, at 0 degrees C, but was then gradually released prior to the formation of the larger RNA fragment. It cannot be concluded, therefore, as it was earlier (Gray et al., 1973), that this RNA fragment contains the primary binding site of L18....

  16. Protein expression on Cr resistant microorganism using electrophoresis method

    Directory of Open Access Journals (Sweden)

    SAJIDAN

    2009-01-01

    Full Text Available Fatmawati U, Suranto, Sajidan. 2009. Protein expression on Cr resistant microorganism using electrophoresis method. Nusantara Bioscience 1: 31-37. Hexavalent chromium (Cr(VI is known as toxic heavy metals, so the need is reduced to Cr(III is much less toxicity. Pseudomonas aeruginosa, Pseudomonas putida, Klebsiella pneumoniae, Pantoea sp. and Saccharomyces cerevisiae are resistant Cr(VI microorganism and have ability to reduce Cr(VI. The aim of this research is to know ability of microorganism to reduce Cr(VI and to know protein band pattern between Cr(VI resistant microorganism and non resistant microorganism which inoculated on LB broth. SDS-PAGE was used to indentify protein expression. While, Cr(VI concentration was identified by 1.5 diphenylcarbazide method. The quantitative data was analyzed by two factorial ANOVA that continued with DMRT at 1% level test. The qualitative data i.e. protein expression analyzed by relative mobility (Rf. The results showed that the ability of microorganisms to reduce Cr(VI at initial concentration of 0.5 ppm, 1 ppm, 5 ppm and 10 ppm may vary, the average percentage of the ability of each microorganism in reducing Cr(VI is P. putida (65% > S. cerevisiae (64.45% >. P. aeruginosa (60.73% > Pantoea sp. (50.22% > K. pneumoniae (47.82% > without microorganisms (34.25%. The adding microorganisms have significantly influenced toward reduction of Cr(VI. The SDS-PAGE shows that protein expression between resistant and not resistant microorganisms are no different, but resistant microorganisms have more protein (protein band is thicker.

  17. Bipolar resistive switching in different plant and animal proteins

    KAUST Repository

    Bag, A.

    2014-06-01

    We report bipolar resistive switching phenomena observed in different types of plant and animal proteins. Using protein as the switching medium, resistive switching devices have been fabricated with conducting indium tin oxide (ITO) and Al as bottom and top electrodes, respectively. A clockwise bipolar resistive switching phenomenon is observed in all proteins. It is shown that the resistive switching phenomena originate from the local redox process in the protein and the ion exchange from the top electrode/protein interface.

  18. Predicting Resistance Mutations Using Protein Design Algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Frey, K.; Georgiev, I; Donald, B; Anderson, A

    2010-01-01

    Drug resistance resulting from mutations to the target is an unfortunate common phenomenon that limits the lifetime of many of the most successful drugs. In contrast to the investigation of mutations after clinical exposure, it would be powerful to be able to incorporate strategies early in the development process to predict and overcome the effects of possible resistance mutations. Here we present a unique prospective application of an ensemble-based protein design algorithm, K*, to predict potential resistance mutations in dihydrofolate reductase from Staphylococcus aureus using positive design to maintain catalytic function and negative design to interfere with binding of a lead inhibitor. Enzyme inhibition assays show that three of the four highly-ranked predicted mutants are active yet display lower affinity (18-, 9-, and 13-fold) for the inhibitor. A crystal structure of the top-ranked mutant enzyme validates the predicted conformations of the mutated residues and the structural basis of the loss of potency. The use of protein design algorithms to predict resistance mutations could be incorporated in a lead design strategy against any target that is susceptible to mutational resistance.

  19. Comparing lamin proteins post-translational relative stability using a 2A peptide-based system reveals elevated resistance of progerin to cellular degradation

    Science.gov (United States)

    Wu, Di; Zhang, Haoyue; Cao, Kan

    2016-01-01

    ABSTRACT Nuclear lamins are the major components of the nuclear lamina at the periphery of the nucleus, supporting the nuclear envelope and participating in many nuclear processes, including DNA replication, transcription and chromatin organization. A group of diseases, the laminopathies, is associated with mutations in lamin genes. One of the most striking cases is Hutchinson-Gilford progeria syndrome (HGPS) which is the consequence of a lamin A dominant negative mutant named progerin. Due to the abnormal presence of a permanent C-terminal farnesyl tail, progerin gradually accumulates on the nuclear membrane, perturbing a diversity of signalings and transcriptional events. The accumulation of progerin has led to the speculation that progerin possesses higher stability than the wild type lamin A protein. However, the low solubility of lamin proteins renders traditional immunoprecipitation-dependent methods such as pulse-chase analysis ineffective for comparing the relative stabilities of mutant and wild type lamins. Here, we employ a novel platform for inferring differences in lamin stability, which is based on normalization to a co-translated reporter protein following porcine teschovirus-1 2A peptide-mediated co-translational cleavage. The results obtained using this method support the notion that progerin is more stable than lamin A. Moreover, treatment of FTI reduces progerin relative stability to the level of wild type lamin A. PMID:27929926

  20. 耐药相关蛋白P-gp、MRP、LRP在非小细胞肺癌组织中的表达及意义%The expression and significance of the multidrug resistance-related proteins P-gp, MRP and LRP in human non-small cell lung cancer tissues

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective: To explore the expression and significance of the multidrug resistance-related proteins P-glycoprotein (P-gp), multidrug resistance-related protein (MRP), lung resistance protein (LRP) in human non-small cell lung cancer (NSCLC) tissues and paratumor tissues. Methods: Immunohistochemistry (IHC) was used to examine the expression level of proteins P-gp, MRP and LRP in 43 samples of NSCLC and 15 samples of paratumor tissues. Results: The expression rates of P-gp, MRP and LRP in 43 tumor tissues were 74.42% (32/43), 67.44% (29/43) and 88.37% (38/43), respectively, while in 15 paratumor tissues were 13.33% (2/15), 20.00% (3/15) and 6.67% (1/15), respectively. There was significant difference in the expression of proteins (P-gp, MRP and LRP) between lung cancer tissues and paratumor tissues (P < 0.05). The expression of proteins P-gp, LRP in lung adenocarcinoma were higher than that in other pathological carcinomas (P < 0.05). The expression of protein MRP was not related to pathological type, clinical stage and classification of histodifferentiation (P >0.05). Conclusion: Multidrug resistance is more common in NSCLC. The proteins of P-gp, MRP and LRP participated in the formation of multidrug resistance in lung cancer. Detection of multidrug resistance-related proteins in lung cancer tissues may be useful to choice drugs.

  1. The crystal structure of Rv1347c, a putative antibiotic resistance protein from Mycobacterium tuberculosis, reveals a GCN5-related fold and suggests an alternative function in siderophore biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Card, G L; Peterson, N A; Smith, C A; Rupp, B; Schick, B M; Baker, E N

    2005-02-15

    Mycobacterium tuberculosis, the cause of TB, is a devastating human pathogen. The emergence of multi-drug resistance in recent years has prompted a search for new drug targets and for a better understanding of mechanisms of resistance. Here we focus on the gene product of an open reading frame from M. tuberculosis, Rv1347c, which is annotated as a putative aminoglycoside N-acetyltransferase. The Rv1347c protein does not show this activity, however, and we show from its crystal structure, coupled with functional and bioinformatic data, that its most likely role is in the biosynthesis of mycobactin, the M. tuberculosis siderophore. The crystal structure of Rv1347c was determined by MAD phasing from selenomethionine-substituted protein and refined at 2.2 {angstrom} resolution (R = 0.227, R{sub free} = 0.257). The protein is monomeric, with a fold that places it in the GCN5-related N-acetyltransferase (GNAT) family of acyltransferases. Features of the structure are an acylCoA binding site that is shared with other GNAT family members, and an adjacent hydrophobic channel leading to the surface that could accommodate long-chain acyl groups. Modeling the postulated substrate, the N{sup {var_epsilon}}-hydroxylysine side chain of mycobactin, into the acceptor substrate binding groove identifies two residues at the active site, His130 and Asp168, that have putative roles in substrate binding and catalysis.

  2. Diminished expression of multidrug resistance-associated protein 1 (MRP1) in bronchial epithelium of COPD patients

    NARCIS (Netherlands)

    van der Deen, Margaretha; Marks, Hendrik; Willemse, Brigitte W. M.; Postma, Dirkje S.; Muller, Michael; Smit, Egbert F.; Scheffer, George L.; Scheper, Rik J.; de Vries, Elisabeth G. E.; Timens, Wim

    2006-01-01

    Cigarette smoke is the principal risk factor for chronic obstructive pulmonary disease (COPD). Multidrug resistance proteins, such as multidrug resistance-associated protein-1 (MRP1), P-glycoprotein (P-gp), and lung resistance-related protein (LRP), may protect against oxidative stress and toxic com

  3. Role of glutathione, glutathione S-transferases and multidrug resistance-related proteins in cisplatin sensitivity of head and neck cancer cell lines

    NARCIS (Netherlands)

    Welters, M.J.P.; Fichtinger-Schepman, A.M.J.; Baan, R.A.; Flens, M.J.; Scheper, R.J.; Braakhuis, B.J.M.

    1998-01-01

    Resistance to chemotherapy is a major problem in the treatment of patients with head and neck squamous cell carcinoma (HNSCC). Important factors involved are drug detoxification by glutathione (GSH) and reduced drug accumulation due to active transport out of the cell by so-called 'multidrug resista

  4. Molecular cloning and functional analysis of three genes encoding polygalacturonase-inhibiting proteins from Capsicum annuum, and their relation to increased resistance to two fungal pathogens

    Science.gov (United States)

    Polygalacturonase-inhibiting proteins (PGIPs) are plant cell wall glycoproteins that can inhibit fungal endopolygalacturonases (PGs). Inhibiting by PGIPs directly reduces potential PG activity in specific plant pathogenic fungi, reducing their aggressiveness. Here, we isolated and functionally chara...

  5. Tomato yellow leaf curl Sardinia virus-resistant tomato plants expressing the multifunctional N-terminal domain of the replication-associated protein show transcriptional changes resembling stress-related responses.

    Science.gov (United States)

    Lucioli, Alessandra; Berardi, Alessandra; Gatti, Francesca; Tavazza, Raffaela; Pizzichini, Daniele; Tavazza, Mario

    2014-01-01

    The N-terminal domain (amino acids 1-130) of the replication-associated protein (Rep130 ) of Tomato yellow leaf curl Sardinia virus (TYLCSV) retains the ability of full-length Rep to localize to the nucleus and to down-regulate C1 transcription when ectopically expressed in plants, both functions being required to inhibit homologous viral replication. In this study, we analysed the effect of Rep130 expression on virus resistance and the plant transcriptome in the natural and agronomically important host species of TYLCSV, Solanum lycopersicum. Tomato plants accumulating high levels of Rep130 were generated and proved to be resistant to TYLCSV. Using an in vitro assay, we showed that plant-expressed Rep130 also retains the catalytic activity of Rep, thus supporting the notion that this protein domain is fully functional. Interestingly, Rep130 -expressing tomatoes were characterized by an altered transcriptional profile resembling stress-related responses. Notably, the serine-type protease inhibitor (Ser-PI) category was over-represented among the 20 up-regulated genes. The involvement of Rep130 in the alteration of host mRNA steady-state levels was confirmed using a distinct set of virus-resistant transgenic tomato plants expressing the same TYLCSV Rep130 , but from a different, synthetic, gene. Eight genes were found to be up-regulated in both types of transgenic tomato and two encoded Ser-PIs. Four of these eight genes were also up-regulated in TYLCSV-infected wild-type tomato plants. Implications with regard to the ability of this Rep domain to interfere with viral infections and to alter the host transcriptome are discussed.

  6. Green tea polyphenols improve cardiac muscle mRNA, and protein levels of signal pathways related to insulin and lipid metabolism and inflammation in insulin-resistant rats

    Science.gov (United States)

    Epidemiologic studies indicate that the consumption of green tea polyphenols (GTP) may reduce the risk of coronary artery disease. To explore the underlying mechanisms of action at the molecular level, we examined the effects of GTP on cardiac mRNA and protein levels of genes involved in insulin an...

  7. Parathyroid hormone-related protein blood test

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003691.htm Parathyroid hormone-related protein blood test To use the ... features on this page, please enable JavaScript. The parathyroid hormone-related protein (PTH-RP) test measures the ...

  8. Alterations of Dopamine D2 Receptors and Related Receptor-Interacting Proteins in Schizophrenia: The Pivotal Position of Dopamine Supersensitivity Psychosis in Treatment-Resistant Schizophrenia

    Directory of Open Access Journals (Sweden)

    Yasunori Oda

    2015-12-01

    Full Text Available Although the dopamine D2 receptor (DRD2 has been a main target of antipsychotic pharmacotherapy for the treatment of schizophrenia, the standard treatment does not offer sufficient relief of symptoms to 20%–30% of patients suffering from this disorder. Moreover, over 80% of patients experience relapsed psychotic episodes within five years following treatment initiation. These data strongly suggest that the continuous blockade of DRD2 by antipsychotic(s could eventually fail to control the psychosis in some point during long-term treatment, even if such treatment has successfully provided symptomatic improvement for the first-episode psychosis, or stability for the subsequent chronic stage. Dopamine supersensitivity psychosis (DSP is historically known as a by-product of antipsychotic treatment in the manner of tardive dyskinesia or transient rebound psychosis. Numerous data in psychopharmacological studies suggest that the up-regulation of DRD2, caused by antipsychotic(s, is likely the mechanism underlying the development of the dopamine supersensitivity state. However, regardless of evolving notions of dopamine signaling, particularly dopamine release, signal transduction, and receptor recycling, most of this research has been conducted and discussed from the standpoint of disease etiology or action mechanism of the antipsychotic, not of DSP. Hence, the mechanism of the DRD2 up-regulation or mechanism evoking clinical DSP, both of which are caused by pharmacotherapy, remains unknown. Once patients experience a DSP episode, they become increasingly difficult to treat. Light was recently shed on a new aspect of DSP as a treatment-resistant factor. Clarification of the detailed mechanism of DSP is therefore crucial, and a preventive treatment strategy for DSP or treatment-resistant schizophrenia is urgently needed.

  9. CD34-related coexpression of MDR1 and BCRP indicates a clinically resistant phenotype in patients with acute myeloid leukemia (AML) of older age

    NARCIS (Netherlands)

    van den Heuvel-Eibrink, Marry M.; van der Holt, Bronno; Burnett, Alan K.; Knauf, Wolfgang U.; Fey, Martin F.; Verhoef, Gregor E. G.; Vellenga, Edo; Ossenkoppele, Gert J.; Lowenberg, Bob; Sonneveld, Pieter

    Clinical resistance to chemotherapy in acute myeloid leukemia (AML) is associated with the expression of the multidrug resistance (MDR) proteins P-glycoprotein, encoded by the MDR1/ABCB1 gene, multidrug resistant-related protein (MRP/ABCC1), the lung resistance-related protein (LRP), or major vault

  10. Structural protein alterations to resistance and endurance cycling exercise training.

    Science.gov (United States)

    Parcell, Allen C; Woolstenhulme, Mandy T; Sawyer, Robert D

    2009-03-01

    The muscle cytoskeleton is necessary for the effective transmission of forces generated by actin-myosin interactions. We have examined the impact of muscle force and exercise volume on the cytoskeleton by measuring desmin and dystrophin content in human skeletal muscle after 12 weeks of progressive resistance or endurance cycle training. Muscle biopsies of the vastus lateralis were obtained before and after training. Desmin and dystrophin content was determined using immunoblotting techniques. After resistance training, desmin content increased 82 +/- 18% (p < 0.05), whereas there was no change in desmin content with endurance cycling. Dystrophin content did not change in either group. One-repetition maximum and VO2max increased (p < 0.05) in the resistance and endurance groups, respectively. These data demonstrate that a high-tension stimulus impacts the cytoskeleton in contrast to high-volume concentric contractions. The tensile loading and eccentric components of resistance training are implicated in desmin alterations. Indeed, the functional improvements resulting from resistance training may be related in part to the mechanical integration provided by the desmin protein.

  11. Cloning and functional analysis of three genes encoding polygalacturonase-inhibiting proteins from Capsicum annuum and transgenic CaPGIP1 in tobacco in relation to increased resistance to two fungal pathogens.

    Science.gov (United States)

    Wang, Xiuju; Zhu, Xiaoping; Tooley, Paul; Zhang, Xiuguo

    2013-03-01

    Polygalacturonase-inhibiting proteins (PGIPs) are plant cell wall glycoproteins that can inhibit fungal endopolygalacturonases (PGs). The PGIPs directly reduce the aggressive potential of PGs. Here, we isolated and functionally characterized three members of the pepper (Capsicum annuum) PGIP gene family. Each was up-regulated at a different time following stimulation of the pepper leaves by Phytophthora capcisi and abiotic stresses including salicylic acid, methyl jasmonate, abscisic acid, wounding and cold treatment. Purified recombinant proteins individually inhibited activity of PGs produced by Alternaria alternata and Colletotrichum nicotianae, respectively, and virus-induced gene silencing in pepper conferred enhanced susceptibility to P. capsici. Because three PGIP genes acted similarily in conferring resistance to infection by P. capsici, and because individually purified proteins showed consistent inhibition against PG activity of both pathogens, CaPGIP1 was selected for manipulating transgenic tobacco. The crude proteins from transgenic tobacco exhibited distinct enhanced resistance to PG activity of both fungi. Moreover, the transgenic tobacco showed effective resistance to infection and a significant reduction in the number of infection sites, number of lesions and average size of lesions in the leaves. All results suggest that CaPGIPs may be involved in plant defense response and play an important role in a plant's resistance to disease.

  12. Extracellular Proteins: Novel Key Components of Metal Resistance in Cyanobacteria?

    Science.gov (United States)

    Giner-Lamia, Joaquín; Pereira, Sara B; Bovea-Marco, Miquel; Futschik, Matthias E; Tamagnini, Paula; Oliveira, Paulo

    2016-01-01

    Metals are essential for all living organisms and required for fundamental biochemical processes. However, when in excess, metals can turn into highly-toxic agents able to disrupt cell membranes, alter enzymatic activities, and damage DNA. Metal concentrations are therefore tightly controlled inside cells, particularly in cyanobacteria. Cyanobacteria are ecologically relevant prokaryotes that perform oxygenic photosynthesis and can be found in many different marine and freshwater ecosystems, including environments contaminated with heavy metals. As their photosynthetic machinery imposes high demands for metals, homeostasis of these micronutrients has been widely studied in cyanobacteria. So far, most studies have focused on how cells are capable of controlling their internal metal pools, with a strong bias toward the analysis of intracellular processes. Ultrastructure, modulation of physiology, dynamic changes in transcription and protein levels have been studied, but what takes place in the extracellular environment when cells are exposed to an unbalanced metal availability remains largely unknown. The interest in studying the subset of proteins present in the extracellular space has only recently begun and the identification and functional analysis of the cyanobacterial exoproteomes are just emerging. Remarkably, metal-related proteins such as the copper-chaperone CopM or the iron-binding protein FutA2 have already been identified outside the cell. With this perspective, we aim to raise the awareness that metal-resistance mechanisms are not yet fully known and hope to motivate future studies assessing the role of extracellular proteins on bacterial metal homeostasis, with a special focus on cyanobacteria.

  13. A symmetry-related sequence-structure relation of proteins

    Institute of Scientific and Technical Information of China (English)

    XU Ruizhen; LI Mingfen; CHEN Hanlin; HUANG Yanzhao; XIAO Yi

    2005-01-01

    Proteins have regular tertiary structures but irregular amino acid sequences. This made it very difficult to decode the structural information in the protein sequences. Here we demonstrate that many small αprotein domains have hidden sequence symmetries characteristic of their pseudo-symmetric tertiary structures. We also present a modified method of recurrent plot to reveal this kind of the hidden sequence symmetry. The results may enable us to understand part of the relations between protein sequences and their tertiary structures.

  14. Transporter protein and drug resistance of Trypanosoma.

    Science.gov (United States)

    Medina, Noraine P; Mingala, Claro N

    2016-01-01

    Trypanosoma infection is one of the most important infections in livestock and humans. One of the main problems of its therapeutic control and treatment is the resurgence of drug resistance. One of the most studied causes of such resistance is the function of its adenosine transporter gene. A trypanosomal gene TbAT1 from Trypanosoma brucei has been cloned in yeast to demonstrate its function in the transport of adenosine and trypanocidal agents. Drug resistant trypanosomes showed a defective TbAT1 variant; furthermore, deletion of the gene and set point mutations in the transporter gene has been demonstrated from isolates from relapse patients. The molecular understanding of the mechanism of action trypanocidal agents and function of transporter gene can lead to control of drug resistance of Trypanosomes.

  15. Increased Prevalence of Activated Protein C Resistance During ...

    African Journals Online (AJOL)

    levels of PCA ratio (measure of protein C resistance) of among our pregnant women since maternal mortality rate of the .... events in most developed countries where changes, which ... Height and weight are measured, and the body mass.

  16. Proteomics Identification of Differentially Expressed Leaf Proteins in Response to Setosphaeria turcica Infection in Resistant Maize

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-li; SI Bing-wen; FAN Cheng-ming; LI Hong-jie; WANG Xiao-ming

    2014-01-01

    Northern corn leaf blight (NCLB), caused by the heterothallic ascomycete fungus Setosphaeria turcica, is a destructive foliar disease of maize and represents a serious threat to maize production worldwide. A comparative proteomic study was conducted to explore the molecular mechanisms underlying the defense responses of the maize resistant line A619 Ht2 to S. turcica race 13. Leaf proteins were extracted from mock and S. turcica-infected leaves after inoculated for 72 h and analyzed for differentially expressed proteins using two-dimensional electrophoresis and mass spectrometry identiifcation. 137 proteins showed reproducible differences in abundance by more than 2-fold at least, including 50 up-regulated proteins and 87 down-regulated proteins. 48 protein spots were successfully identiifed by MS analysis, which included 10 unique, 6 up-regulated, 20 down-regulated and 12 disappeared protein spots. These identiifed proteins were classiifed into 9 functional groups and involved in multiple functions, particularly in energy metabolism (46%), protein destination and storage (12%), and disease defense (18%). Some defense-related proteins were upregulated such asβ-glucosidase, SOD, polyamines oxidase, HSC 70 and PPIases; while the expressions of photosynthesis- and metabolism-related proteins were down-regulated, by inoculation with S. turcica. The results indicated that a complex regulatory network was functioned in interaction between the resistant line A619 Ht2 and S. turcica. The resistance processes of A619 Ht2 mainly resided on directly releasing defense proteins, modulation of primary metabolism, affecting photosyntesis and carbohydrate metabolism.

  17. Contemporary Issues in Protein Requirements and Consumption for Resistance Trained Athletes

    Directory of Open Access Journals (Sweden)

    Wilson Jacob

    2006-06-01

    Full Text Available Abstract In recent years an explosion of research papers concerning protein consumption has been published. The need to consolidate this information has become critical from both practical and future research standpoints. For this reason, the following paper presents an in depth analysis of contemporary issues in protein requirements and consumption for resistance trained athletes. Specifically, the paper covers: 1. protein requirements for resistance trained athletes; 2. the effect of the digestion rate of protein on muscular protein balance; 3. the optimal timing of protein intake relative to exercise; 4. the optimal pattern of protein ingestion, relative to how an individual should consume their protein throughout a 24 hour period, and what sources are utilized during this time frame; 5. protein composition and its interaction with measures of protein balance and strength performance; 6. the combination of protein and carbohydrates on plasma insulin levels and protein balance; 7. the efficacy of protein supplements and whole food protein sources. Our goal is to provide the reader with practical information in optimizing protein intake as well as for provision of sound advice to their clients. Finally, special care was taken to provide future research implications.

  18. Expression of multidrug resistance-related markers in primary neuroblastoma

    Institute of Scientific and Technical Information of China (English)

    吕庆杰; 董芳; 张锦华; 李晓晗; 马颖; 姜卫国

    2004-01-01

    Background Multidrug resistance is associated with a poor prognosis in various human cancers. However, the clinical significance of the expression of multidrug resistance-related markers in neuroblastoma is still on debate. In this study, the effect of the expression of p-glycoprotein (P-gp), multidrug resistance-associated protein (MRP), and lung resistance protein (LRP) in neuroblastoma was evaluated. Methods The streptavidin-biotin immunoperoxidase (SP) technique was used to evaluate the expression of P-gp, MRP, and LRP in 70 cases of untreated primary neuroblastoma. Results The frequencies of the expression of P-gp, MRP, and LRP were 61.4%, 38.6%, and 24.3%, respectively. A significant positive correlation was observed between P-gp and MRP expression (P=0.001), as well as between LRP and MRP expression (P=0.01). The rates of expression of P-gp and MRP were higher in tumors from patients aged greater than one year old than in tumors from patients aged less than 1 year old at time of diagnosis (P=0.01 and 0.018, respectively). MRP expression in tumors that had metastasized was significantly more frequent than in tumors that had not metastasized (P=0.015). The expression of all tested proteins showed a significant relationship with whether or not the tumor had differentiated (P=0.006, 0.000 or 0.001, respectively). MRP expression was significantly associated with a reduction in both median survival time and 2-year cumulative survival (P=0.02). By contrast, P-gp and MRP expression did not correlate with survival. According to Cox regression analysis, only the co-expression of P-gp and MRP had significant prognostic value (relative hazard, 3.513, P=0.033). Conclusions The intrinsic, multidrug resistance of neuroblastoma involves the combined effects of P-gp, MRP, and LRP. MRP expression may be an important factor determining prognosis in neuroblastoma.

  19. ABC-F Proteins Mediate Antibiotic Resistance through Ribosomal Protection.

    Science.gov (United States)

    Sharkey, Liam K R; Edwards, Thomas A; O'Neill, Alex J

    2016-03-22

    Members of the ABC-F subfamily of ATP-binding cassette proteins mediate resistance to a broad array of clinically important antibiotic classes that target the ribosome of Gram-positive pathogens. The mechanism by which these proteins act has been a subject of long-standing controversy, with two competing hypotheses each having gained considerable support: antibiotic efflux versus ribosomal protection. Here, we report on studies employing a combination of bacteriological and biochemical techniques to unravel the mechanism of resistance of these proteins, and provide several lines of evidence that together offer clear support to the ribosomal protection hypothesis. Of particular note, we show that addition of purified ABC-F proteins to anin vitrotranslation assay prompts dose-dependent rescue of translation, and demonstrate that such proteins are capable of displacing antibiotic from the ribosomein vitro To our knowledge, these experiments constitute the first direct evidence that ABC-F proteins mediate antibiotic resistance through ribosomal protection.IMPORTANCEAntimicrobial resistance ranks among the greatest threats currently facing human health. Elucidation of the mechanisms by which microorganisms resist the effect of antibiotics is central to understanding the biology of this phenomenon and has the potential to inform the development of new drugs capable of blocking or circumventing resistance. Members of the ABC-F family, which includelsa(A),msr(A),optr(A), andvga(A), collectively yield resistance to a broader range of clinically significant antibiotic classes than any other family of resistance determinants, although their mechanism of action has been controversial since their discovery 25 years ago. Here we present the first direct evidence that proteins of the ABC-F family act to protect the bacterial ribosome from antibiotic-mediated inhibition. Copyright © 2016 Sharkey et al.

  20. Current Overview of Allergens of Plant Pathogenesis Related Protein Families

    Directory of Open Access Journals (Sweden)

    Mau Sinha

    2014-01-01

    Full Text Available Pathogenesis related (PR proteins are one of the major sources of plant derived allergens. These proteins are induced by the plants as a defense response system in stress conditions like microbial and insect infections, wounding, exposure to harsh chemicals, and atmospheric conditions. However, some plant tissues that are more exposed to environmental conditions like UV irradiation and insect or fungal attacks express these proteins constitutively. These proteins are mostly resistant to proteases and most of them show considerable stability at low pH. Many of these plant pathogenesis related proteins are found to act as food allergens, latex allergens, and pollen allergens. Proteins having similar amino acid sequences among the members of PR proteins may be responsible for cross-reactivity among allergens from diverse plants. This review analyzes the different pathogenesis related protein families that have been reported as allergens. Proteins of these families have been characterized in regard to their biological functions, amino acid sequence, and cross-reactivity. The three-dimensional structures of some of these allergens have also been evaluated to elucidate the antigenic determinants of these molecules and to explain the cross-reactivity among the various allergens.

  1. Current Overview of Allergens of Plant Pathogenesis Related Protein Families

    Science.gov (United States)

    Sinha, Mau; Singh, Rashmi Prabha; Kushwaha, Gajraj Singh; Iqbal, Naseer; Singh, Avinash; Kaushik, Sanket; Sharma, Sujata; Singh, Tej P.

    2014-01-01

    Pathogenesis related (PR) proteins are one of the major sources of plant derived allergens. These proteins are induced by the plants as a defense response system in stress conditions like microbial and insect infections, wounding, exposure to harsh chemicals, and atmospheric conditions. However, some plant tissues that are more exposed to environmental conditions like UV irradiation and insect or fungal attacks express these proteins constitutively. These proteins are mostly resistant to proteases and most of them show considerable stability at low pH. Many of these plant pathogenesis related proteins are found to act as food allergens, latex allergens, and pollen allergens. Proteins having similar amino acid sequences among the members of PR proteins may be responsible for cross-reactivity among allergens from diverse plants. This review analyzes the different pathogenesis related protein families that have been reported as allergens. Proteins of these families have been characterized in regard to their biological functions, amino acid sequence, and cross-reactivity. The three-dimensional structures of some of these allergens have also been evaluated to elucidate the antigenic determinants of these molecules and to explain the cross-reactivity among the various allergens. PMID:24696647

  2. Extracellular proteins: Novel key components of metal resistance in cyanobacteria?

    Directory of Open Access Journals (Sweden)

    Joaquin eGiner-Lamia

    2016-06-01

    Full Text Available Metals are essential for all living organisms and required for fundamental biochemical processes. However, when in excess, metals can turn into highly-toxic agents able to disrupt cell membranes, alter enzymatic activities and damage DNA. Metal concentrations are therefore tightly controlled inside cells, particularly in cyanobacteria. Cyanobacteria are ecologically relevant prokaryotes that perform oxygenic photosynthesis and can be found in many different marine and freshwater ecosystems, including environments contaminated with heavy metals. As their photosynthetic machinery imposes high demands for metals, homeostasis of these micronutrients has been widely studied in cyanobacteria. So far, most studies have focused on how cells are capable of controlling their internal metal pools, with a strong bias towards the analysis of intracellular processes. Ultrastructure, modulation of physiology, dynamic changes in transcription and protein levels have been studied, but what takes place in the extracellular environment when cells are exposed to an unbalanced metal availability remains largely unknown. The interest in studying the subset of proteins present in the extracellular space has only recently begun and the identification and functional analysis of the cyanobacterial exoproteomes are just emerging. Remarkably, metal-related proteins such as the copper-chaperone CopM or the iron-binding protein FutA2 have already been identified outside the cell. With this perspective, we aim to raise the awareness that metal-resistance mechanisms are not yet fully known and hope to motivate future studies assessing the role of extracellular proteins on bacterial metal homeostasis, with a special focus on cyanobacteria.

  3. Heterologously expressed bacterial and human multidrug resistance proteins confer cadmium resistance to Escherichia coli

    NARCIS (Netherlands)

    Achard-Joris, M; van Saparoea, HBV; Driessen, AJM; Bourdineaud, JP; Bourdineaud, Jean-Paul

    2005-01-01

    The human MDR1 gene is induced by cadmium exposure although no resistance to this metal is observed in human cells overexpressing hMDR1. To access the role of MDR proteins in cadmium resistance, human MDR1, Lactococcus lactis lmrA, and Oenococcus oeni omrA were expressed in an Escherichia coli tolC

  4. Dietary protein to maximize resistance training: a review and examination of protein spread and change theories

    Directory of Open Access Journals (Sweden)

    Bosse John D

    2012-09-01

    Full Text Available Abstract An appreciable volume of human clinical data supports increased dietary protein for greater gains from resistance training, but not all findings are in agreement. We recently proposed “protein spread theory” and “protein change theory” in an effort to explain discrepancies in the response to increased dietary protein in weight management interventions. The present review aimed to extend “protein spread theory” and “protein change theory” to studies examining the effects of protein on resistance training induced muscle and strength gains. Protein spread theory proposed that there must have been a sufficient spread or % difference in g/kg/day protein intake between groups during a protein intervention to see muscle and strength differences. Protein change theory postulated that for the higher protein group, there must be a sufficient change from baseline g/kg/day protein intake to during study g/kg/day protein intake to see muscle and strength benefits. Seventeen studies met inclusion criteria. In studies where a higher protein intervention was deemed successful there was, on average, a 66.1% g/kg/day between group intake spread versus a 10.2% g/kg/day spread in studies where a higher protein diet was no more effective than control. The average change in habitual protein intake in studies showing higher protein to be more effective than control was +59.5% compared to +6.5% when additional protein was no more effective than control. The magnitudes of difference between the mean spreads and changes of the present review are similar to our previous review on these theories in a weight management context. Providing sufficient deviation from habitual intake appears to be an important factor in determining the success of additional protein in enhancing muscle and strength gains from resistance training. An increase in dietary protein favorably effects muscle and strength during resistance training.

  5. Dietary protein to maximize resistance training: a review and examination of protein spread and change theories.

    Science.gov (United States)

    Bosse, John D; Dixon, Brian M

    2012-09-08

    An appreciable volume of human clinical data supports increased dietary protein for greater gains from resistance training, but not all findings are in agreement. We recently proposed "protein spread theory" and "protein change theory" in an effort to explain discrepancies in the response to increased dietary protein in weight management interventions. The present review aimed to extend "protein spread theory" and "protein change theory" to studies examining the effects of protein on resistance training induced muscle and strength gains. Protein spread theory proposed that there must have been a sufficient spread or % difference in g/kg/day protein intake between groups during a protein intervention to see muscle and strength differences. Protein change theory postulated that for the higher protein group, there must be a sufficient change from baseline g/kg/day protein intake to during study g/kg/day protein intake to see muscle and strength benefits. Seventeen studies met inclusion criteria. In studies where a higher protein intervention was deemed successful there was, on average, a 66.1% g/kg/day between group intake spread versus a 10.2% g/kg/day spread in studies where a higher protein diet was no more effective than control. The average change in habitual protein intake in studies showing higher protein to be more effective than control was +59.5% compared to +6.5% when additional protein was no more effective than control. The magnitudes of difference between the mean spreads and changes of the present review are similar to our previous review on these theories in a weight management context. Providing sufficient deviation from habitual intake appears to be an important factor in determining the success of additional protein in enhancing muscle and strength gains from resistance training. An increase in dietary protein favorably effects muscle and strength during resistance training.

  6. Analysis of Differentially Expressed Genes Related to Resistance in Spinosad- and Neonicotinoid-Resistant Musca domestica L. (Diptera: Muscidae) Strains

    Science.gov (United States)

    Højland, Dorte H.

    2017-01-01

    Background The housefly is a global pest that has developed resistance to most insecticides applied against it. Resistance of the spinosad-resistant strain 791spin and the neonicotinoid-resistant 766b strain is believed to be due to metabolism. We investigate differentially expressed genes in these two resistant strains related to metabolism in comparison with an insecticide-susceptible reference strain. Results Genes involved in metabolism of xenobiotics were primarily up-regulated in resistant flies with some differences between resistant strains. The cyp4g98 and cyp6g4 genes proved interesting in terms of neonicotinoid resistance, while cyp4d9 was overexpressed in 791spin compared to spinosad-susceptible strains. GSTs, ESTs and UGTs were mostly overexpressed, but not to the same degree as P450s. We present a comprehensive and comparative picture of gene expression in three housefly strains differing significantly in their response to insecticides. High differential expression of P450s and genes coding for cuticle protein indicates a combination of factors involved in metabolic neonicotinoid and spinosad resistance. Conclusion Resistance in these strains is apparently not linked to the alteration of a single gene but is composed of several changes including differential expression of genes encoding metabolic detoxification enzymes. PMID:28125739

  7. Soy protein allergy: incidence and relative severity.

    Science.gov (United States)

    Cordle, Christopher T

    2004-05-01

    Food allergy is a relatively rare and sometimes violent reaction of the immune system to food proteins. The first report characterizing soy allergy appeared in 1934. The Food and Agriculture Organization of the United Nations includes soy in its list of the 8 most significant food allergens. At least 16 potential soy protein allergens have been identified but their relative clinical significance is unknown. Conversely, soy has a long history of successful use in managing cow's milk allergies in infants. To better predict the utility of soy proteins for controlling food allergy, it is important to understand the relative allergenic reactivity of soy compared with other major food proteins. This can be studied using clinical data, animal models, and biochemical approaches; all show diminished reactivity for soy. Clinical studies using in vitro methods and blinded food challenges have generated substantial information. Study populations include high-risk asymptomatic infants and patients with atopic symptoms, positive food challenges, and specific milk allergies. Generally, these studies show lower allergic reactivity for soy proteins vs. other food allergens. Comparisons of food allergen dose-response relationships for triggering allergic symptoms also demonstrate a higher protein concentration threshold for soy (approximately 100 times), indicating lower allergenic reactivity. Extensive investigations of soy immunological reactivity have also been carried out using animal models. Consistent with clinical results, all of these data show substantially diminished immunological reactivity for soy proteins. Biochemical and immunochemical analyses indicate no striking differences between soy and other food proteins that would explain these unexpected differences in allergenic reactivity.

  8. Expression of xeroderma pigmentosum complementation group C protein predicts cisplatin resistance in lung adenocarcinoma patients.

    Science.gov (United States)

    Lai, Tan-Chen; Chow, Kuan-Chih; Fang, Hsin-Yuan; Cho, Hsin-Ching; Chen, Chih-Yi; Lin, Tze-Yi; Chiang, I-Ping; Ho, Shu-Peng

    2011-05-01

    DNA repair has been suggested to be a major cause of spontaneous drug resistance in patients with lung adenocarcinomas (LADC). Among the DNA repair-related proteins, excision repair cross-complementation group 1 (ERCC1) has been shown to be essential for repairing cisplatin-induced interstrand cross-linkage. However, the role of other DNA repair-related proteins in drug resistance has not been clearly elucidated. In this study, we used suppression subtractive hybridization and microarray analysis to identify the DNA repair-related genes associated with cisplatin resistance. We focused on the association of XPC protein expression, which plays a pivotal role in the earliest response to global genomic repair, with the survival of LADC patients. Using suppression subtractive hybridization and a microarray analysis to identify drug resistance-associated DNA repair-related genes, we found that the mRNA levels of ERCC1, MSH-3, MSH-6 and XPC were significantly increased in LADC patients. Since the results of ERCC1 mRNA expression corresponded well with those in previous reports, in this study we focused on the clinical correlation between XPC expression and patient survival. The level of XPC protein was determined by immunohistochemical and immunoblotting analyses. We detected the XPC protein in 46 (43%) of 107 pathological LADC samples. XPC protein expression correlated with tumor stage, cigarette smoking and poor survival. In the in vitro experiments with LADC cell lines, increased XPC expression was associated with elevated drug resistance, and silencing of XPC expression reduced cisplatin resistance. Our results suggest that XPC expression predicts drug resistance in LADC.

  9. Retinol binding protein 4, obesity, and insulin resistance in adolescents

    Directory of Open Access Journals (Sweden)

    Ronaldi Noor

    2017-02-01

    Full Text Available Background Obesity is a global problem. Even in poor and developing countries, obesity has reached alarming levels. In childhood, obesity may lead to insulin resistance. Retinol binding protein (RBP4, secreted primarily by liver and adipose tissues, was recently proposed as a link between obesity and insulin resistance. The role of RBP4 in pediatric obesity and its relationship with insulin resistance have not been well elucidated. Objective To compare RBP4 levels in obese and lean adolescents and to assess for a relationship between RBP4 levels and insulin resistance. Method This cross-sectional study was conducted in three senior high schools in Padang, West Sumatera, Indonesia. Subjects were adolescents aged 14-18 years, who were obese or normal weight (n=56. We measured subjects’ body mass index (BMI and serum RBP4 concentrations. Insulin resistance was assessed using the homeostasis model assessment of insulin resistance (HOMA-IR index. Results Similar RBP4 levels were found in the obese and normoweight groups (P>0.05. Higher RBP4 levels were found in the insulin resistant compared to the non-insulin resistant group, but the difference was not significant (P > 0.05. Conclusion There is no significant difference in mean RBP4 levels in obese adolescents compared to normoweight adolescents. Nor are mean RBP4 levels significantly different between obese adolescents with and without insulin resistance.

  10. Complement factor H related proteins (CFHRs).

    Science.gov (United States)

    Skerka, Christine; Chen, Qian; Fremeaux-Bacchi, Veronique; Roumenina, Lubka T

    2013-12-15

    Factor H related proteins comprise a group of five plasma proteins: CFHR1, CFHR2, CFHR3, CFHR4 and CFHR5, and each member of this group binds to the central complement component C3b. Mutations, genetic deletions, duplications or rearrangements in the individual CFHR genes are associated with a number of diseases including atypical hemolytic uremic syndrome (aHUS), C3 glomerulopathies (C3 glomerulonephritis (C3GN), dense deposit disease (DDD) and CFHR5 nephropathy), IgA nephropathy, age related macular degeneration (AMD) and systemic lupus erythematosus (SLE). Although complement regulatory functions were attributed to most of the members of the CFHR protein family, the precise role of each CFHR protein in complement activation and the exact contribution to disease pathology is still unclear. Recent publications show that CFHR proteins form homo- as well as heterodimers. Genetic abnormalities within the CFHR gene locus can result in hybrid proteins with affected dimerization or recognition domains which cause defective functions. Here we summarize the recent data about CFHR genes and proteins in order to better understand the role of CFHR proteins in complement activation and in complement associated diseases.

  11. Resistive random access memory utilizing ferritin protein with Pt nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Uenuma, Mutsunori; Kawano, Kentaro; Zheng Bin; Okamoto, Naofumi; Horita, Masahiro; Yoshii, Shigeo; Yamashita, Ichiro; Uraoka, Yukiharu, E-mail: uenuma@ms.naist.jp [Nara Institute of Science and Technology, 8916-5, Takayama, Ikoma, Nara 630-0192 (Japan)

    2011-05-27

    This study reports controlled single conductive paths found in resistive random access memory (ReRAM) formed by embedding Pt nanoparticles (Pt NPs) in NiO film. Homogeneous Pt NPs produced and placed by ferritin protein produce electric field convergence which leads to controlled conductive path formation. The ReRAM with Pt NPs shows stable switching behavior. A Pt NP density decrease results in an increase of OFF state resistance and decrease of forming voltage, whereas ON resistance was independent of the Pt NP density, which indicates that a single metal NP in a memory cell will achieve low power and stable operation.

  12. Synergistic effects of resistance training and protein intake: practical aspects.

    Science.gov (United States)

    Guimarães-Ferreira, Lucas; Cholewa, Jason Michael; Naimo, Marshall Alan; Zhi, X I A; Magagnin, Daiane; de Sá, Rafaele Bis Dal Ponte; Streck, Emilio Luiz; Teixeira, Tamiris da Silva; Zanchi, Nelo Eidy

    2014-10-01

    Resistance training is a potent stimulus to increase skeletal muscle mass. The muscle protein accretion process depends on a robust synergistic action between protein intake and overload. The intake of protein after resistance training increases plasma amino acids, which results in the activation of signaling molecules leading to increased muscle protein synthesis (MPS) and muscle hypertrophy. Although both essential and non-essential amino acids are necessary for hypertrophy, the intake of free L-leucine or high-leucine whole proteins has been specifically shown to increase the initiation of translation that is essential for elevated MPS. The literature supports the use of protein intake following resistance-training sessions to enhance MPS; however, less understood are the effects of different protein sources and timing protocols on MPS. The sum of the adaptions from each individual training session is essential to muscle hypertrophy, and thus highlights the importance of an optimal supplementation protocol. The aim of this review is to present recent findings reported in the literature and to discuss the practical application of these results. In that light, new speculations and questions will arise that may direct future investigations. The information and recommendations generated in this review should be of benefit to clinical dietitians as well as those engaged in sports.

  13. Tunable protein-resistance of polycation-terminated polyelectrolyte multilayers.

    Science.gov (United States)

    Tristán, Ferdinando; Palestino, Gabriela; Menchaca, J-Luis; Pérez, Elías; Atmani, Hassan; Cuisinier, Frédéric; Ladam, Guy

    2009-08-10

    The prevention of nonspecific protein adsorption is a crucial prerequisite for many biomedical and biotechnological applications. Therefore, the design of robust and versatile methods conferring optimal protein-resistance properties to surfaces has become a challenging issue. Here we report the unexpected case of polycation-ending polyelectrolyte multilayers (PEM) that efficiently prevented the adsorption of a negatively charged model protein, glucose oxidase (GOX). PEM films were based on two typical weak poyelectrolytes: poly(allylamine hydrochloride) (PAH) and poly(acrylic acid) (PAA). No chemical modification of the polyelectrolytes was required and tunable GOX adsorption was possible by simply changing the buildup pH conditions. Protein-resistance properties are attributed to high film hydration becoming the predominant factor over electrostatic interactions. We explain this effect by oscillations of the internal PAA ionization state throughout the buildup, which results in an excess of carboxylic acid groups within the film. This excess acts as a reservoir of potential carboxylate groups compensating the outer PAH positive charges. Partial results indicated that the system was also resistant to the adsorption of a positively charged protein, lysozyme. Control of the internal ionization of weak polyelectrolyte multilayers might open a route toward simple tuning of protein adsorption. These results should help to rationalize the design of biomaterials, biosensors, or protein separation devices.

  14. Mobile genetic elements related to carbapenem resistance in Acinetobacter baumannii

    Directory of Open Access Journals (Sweden)

    Mariana Pagano

    Full Text Available Abstract Acinetobacter baumannii is widely recognized as an important pathogen associated with nosocomial infections. The treatment of these infections is often difficult due to the acquisition of resistance genes. A. baumannii presents a high genetic plasticity which allows the accumulation of these resistance determinants leading to multidrug resistance. It is highlighted the importance of the horizontal transfer of resistance genes, through mobile genetic elements and its relationship with increased incidence of multidrug resistant A. baumannii in hospitals. Considering that resistance to carbapenems is very important from the clinical and epidemiological point of view, the aim of this article is to present an overview of the current knowledge about genetic elements related to carbapenem resistance in A. baumannii such as integrons, transposons, resistance islands and insertion sequences.

  15. Structural basis of protein oxidation resistance: a lysozyme study.

    Directory of Open Access Journals (Sweden)

    Marion Girod

    Full Text Available Accumulation of oxidative damage in proteins correlates with aging since it can cause irreversible and progressive degeneration of almost all cellular functions. Apparently, native protein structures have evolved intrinsic resistance to oxidation since perfectly folded proteins are, by large most robust. Here we explore the structural basis of protein resistance to radiation-induced oxidation using chicken egg white lysozyme in the native and misfolded form. We study the differential resistance to oxidative damage of six different parts of native and misfolded lysozyme by a targeted tandem/mass spectrometry approach of its tryptic fragments. The decay of the amount of each lysozyme fragment with increasing radiation dose is found to be a two steps process, characterized by a double exponential evolution of their amounts: the first one can be largely attributed to oxidation of specific amino acids, while the second one corresponds to further degradation of the protein. By correlating these results to the structural parameters computed from molecular dynamics (MD simulations, we find the protein parts with increased root-mean-square deviation (RMSD to be more susceptible to modifications. In addition, involvement of amino acid side-chains in hydrogen bonds has a protective effect against oxidation Increased exposure to solvent of individual amino acid side chains correlates with high susceptibility to oxidative and other modifications like side chain fragmentation. Generally, while none of the structural parameters alone can account for the fate of peptides during radiation, together they provide an insight into the relationship between protein structure and susceptibility to oxidation.

  16. Mosaic tetracycline resistance genes encoding ribosomal protection proteins.

    Science.gov (United States)

    Warburton, Philip J; Amodeo, Nina; Roberts, Adam P

    2016-12-01

    First reported in 2003, mosaic tetracycline resistance genes are a subgroup of the genes encoding ribosomal protection proteins (RPPs). They are formed when two or more RPP-encoding genes recombine resulting in a functional chimera. To date, the majority of mosaic genes are derived from sections of three RPP genes, tet(O), tet(W) and tet(32), with others comprising tet(M) and tet(S). In this first review of mosaic genes, we report on their structure, diversity and prevalence, and suggest that these genes may be responsible for an under-reported contribution to tetracycline resistance in bacteria.

  17. [Activated protein C resistance and factor V Leiden: clinical interest].

    Science.gov (United States)

    Guermazi, S; Znazen, R

    2011-10-01

    Activated protein C resistance (APCR) is a coagulation abnormality often linked to FV Leiden mutation, a single nucleotide G1691A substitution resulting in arginine 506→glutamine missense factor V mutation. FV Leiden has a frequency of 20 to 30% in groups of patients with venous thrombosis while it is of 4 to 10% in normal subjects. FV Leiden is considered as a weak risk factor of thrombosis except in homozygote. FV Leiden is implicated in deep venous thrombosis occurrence. Duration of oral anticoagulant treatment is six months in patients developing a first venous thrombosis except in patients with combined defects or a clinical context suggesting a high risk of severe relapse. Detection of APCR by coagulation methods is often used in first intention with a high specificity if plasmas tested are diluted in factor V deficient plasma. Genotyping study is essential to establish the heterozygote or homozygote statute and certain teams perform it directly. Nevertheless, APCR not related to FV Leiden could be an independent thrombosis risk factor. APCR and FV Leiden are included in laboratory investigations of thrombophilic markers in patients less than 50 years with venous thrombosis. In arterial thrombosis, FV Leiden implication is weak or absent. FV Leiden increases the risk of thrombosis in other situations as in patients with cancer. An association with recurrent miscarriages and other vasculoplacental complications is also reported in many studies but the data concerning the efficacy of antithrombotic treatment to prevent recurrence are currently insufficient. Copyright © 2009 Elsevier Masson SAS. All rights reserved.

  18. The novel pterostilbene derivative ANK-199 induces autophagic cell death through regulating PI3 kinase class III/beclin 1/Atg‑related proteins in cisplatin‑resistant CAR human oral cancer cells.

    Science.gov (United States)

    Hsieh, Min-Tsang; Chen, Hao-Ping; Lu, Chi-Cheng; Chiang, Jo-Hua; Wu, Tian-Shung; Kuo, Daih-Huang; Huang, Li-Jiau; Kuo, Sheng-Chu; Yang, Jai-Sing

    2014-08-01

    Pterostilbene is an effective chemopreventive agent against multiple types of cancer cells. A novel pterostilbene derivative, ANK-199, was designed and synthesized by our group. Its antitumor activity and mechanism in cisplatin-resistant CAR human oral cancer cells were investigated in this study. Our results show that ANK-199 has an extremely low toxicity in normal oral cell lines. The formation of autophagic vacuoles and acidic vesicular organelles (AVOs) was observed in the ANK-199-treated CAR cells by monodansylcadaverine (MDC) and acridine orange (AO) staining, suggesting that ANK-199 is able to induce autophagic cell death in CAR cells. Neither DNA fragmentation nor DNA condensation was observed, which means that ANK-199-induced cell death is not triggered by apoptosis. In accordance with morphological observation, 3-MA, a specific inhibitor of PI3K kinase class III, can inhibit the autophagic vesicle formation induced by ANK-199. In addition, ANK-199 is also able to enhance the protein levels of autophagic proteins, Atg complex, beclin 1, PI3K class III and LC3-II, and mRNA expression of autophagic genes Atg7, Atg12, beclin 1 and LC3-II in the ANK-199-treated CAR cells. A molecular signaling pathway induced by ANK-199 was therefore summarized. Results presented in this study show that ANK-199 may become a novel therapeutic reagent for the treatment of oral cancer in the near future (patent pending).

  19. Multidrug resistance protein 1 (ABCC1) confers resistance to arsenic compounds in human myeloid leukemic HL-60 cells.

    Science.gov (United States)

    Xu, Shi; Zhang, Yan Fang; Carew, Micheal W; Hao, Wen Hui; Loo, Jacky Fong Chuen; Naranmandura, Hua; Le, X Chris

    2013-06-01

    Arsenic trioxide (As(2)O(3)) is established as one of the most effective drugs for treatment of patients with acute promyelocytic leukemia, as well as other types of malignant tumors. However, HL-60 cells are resistant to As(2)O(3), and little is known about the underlying resistance mechanism for As(2)O(3) and its biomethylation products, namely, monomethylarsonous acid (MMA(III)) on the treatment of tumors. In the present study, we investigated the molecular mechanisms underlying iAs(III) and its intermediate metabolite MMA(III)-induced anticancer effects in the HL-60 cells. Here, we show that the HL-60 cells exhibit resistance to inorganic iAs(III) (IC(50) = 10 μM), but are relatively sensitive to its intermediate MMA(III) (IC(50) = 3.5 μM). Moreover, we found that the multidrug resistance protein 1 (MRP1), but not MRP2, is expressed in HL-60 cells, which reduced the intracellular arsenic accumulation, and conferred resistance to inorganic iAs(III) and MMA(III). Pretreatment of HL-60 with MK571, an inhibitor of MRP1, significantly increased iAs(III) and MMA(III)-induced cytotoxicity and arsenic accumulations, suggesting that the expression of MRP1/4 may lead to HL-60 cells resistance to trivalent arsenic compounds.

  20. Accelerated Degradation of Caspase-8 Protein Correlates with TRAIL Resistance in a DLD1 Human Colon Cancer Cell Line

    Directory of Open Access Journals (Sweden)

    Lidong Zhang

    2005-06-01

    Full Text Available The tumor-selective cytotoxic effect of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL makes TRAIL an attractive candidate as an anticancer agent. However, resistance to TRAIL poses a challenge in anticancer therapy with TRAIL. Therefore, characterizing the mechanisms of resistance and developing strategies to overcome the resistance are important steps toward successful TRAIL-mediated cancer therapy. In this study, we investigated mechanisms of acquired TRAIL resistance in a colon cancer DLD1 cell line. Compared with the TRAIL-susceptible DLD1 cell line, TRAIL-resistant DLD1/TRAIL-R cells have a low level of caspase-8 protein, but not its mRNA. Suppression of caspase-8 expression by siRNA in parental DLD1 cells led to TRAIL resistance. Restoration of caspase-8 protein expression by stable transfection rendered the DLD1/TRAIL-R cell line fully sensitive to TRAIL protein, suggesting that the low level of caspase-8 protein expression might be the culprit in TRAIL resistance in DLDl/TRAIL-R cells. Sequencing analysis of the caspase-8 coding region revealed a missense mutation that is present in both TRAILsensitive and TRAIL-resistant DLD1 cells. Subsequent study showed that the degradation of caspase-8 protein was accelerated in DLDl/TRAIL-R cells compared to parental DLD1 cells. Thus, accelerated degradation of caspase-8 protein is one of the mechanisms that lead to TRAIL resistance.

  1. Intracellular polyamine pools, oligopeptide-binding protein A expression, and resistance to aminoglycosides in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Maria BR Acosta

    2005-11-01

    Full Text Available The role of intracellular free polyamine (putrescine and spermidine pools in multiple resistance to aminoglycoside antibiotics was investigated among in vitro selected kanamycin-resistant Escherichia coli J53 mutants expressing diminished oligopeptide-binding protein (OppA levels and/or defective ornithine decarboxylase (ODC activity. The results suggest that diminished OppA content, but not defective ODC activity expression, increased the relative concentration of free spermidine as compared to the wild type strain. Moreover, by adding exogenous polyamines or polyamine synthesis inhibitors to cultures with different mutant strains, a direct relationship between the intracellular OppA levels and resistance to kanamycin was revealed. Collectively these results further suggest a complex relation among OppA expression, aminoglycoside resistance and polyamine metabolism.

  2. Using Resurrected Ancestral Proviral Proteins to Engineer Virus Resistance

    Directory of Open Access Journals (Sweden)

    Asunción Delgado

    2017-05-01

    Full Text Available Proviral factors are host proteins hijacked by viruses for processes essential for virus propagation such as cellular entry and replication. Pathogens and their hosts co-evolve. It follows that replacing a proviral factor with a functional ancestral form of the same protein could prevent viral propagation without fatally compromising organismal fitness. Here, we provide proof of concept of this notion. Thioredoxins serve as general oxidoreductases in all known cells. We report that several laboratory resurrections of Precambrian thioredoxins display substantial levels of functionality within Escherichia coli. Unlike E. coli thioredoxin, however, these ancestral thioredoxins are not efficiently recruited by the bacteriophage T7 for its replisome and therefore prevent phage propagation in E. coli. These results suggest an approach to the engineering of virus resistance. Diseases caused by viruses may have a devastating effect in agriculture. We discuss how the suggested approach could be applied to the engineering of plant virus resistance.

  3. Predicting disease-related proteins based on clique backbone in protein-protein interaction network.

    Science.gov (United States)

    Yang, Lei; Zhao, Xudong; Tang, Xianglong

    2014-01-01

    Network biology integrates different kinds of data, including physical or functional networks and disease gene sets, to interpret human disease. A clique (maximal complete subgraph) in a protein-protein interaction network is a topological module and possesses inherently biological significance. A disease-related clique possibly associates with complex diseases. Fully identifying disease components in a clique is conductive to uncovering disease mechanisms. This paper proposes an approach of predicting disease proteins based on cliques in a protein-protein interaction network. To tolerate false positive and negative interactions in protein networks, extending cliques and scoring predicted disease proteins with gene ontology terms are introduced to the clique-based method. Precisions of predicted disease proteins are verified by disease phenotypes and steadily keep to more than 95%. The predicted disease proteins associated with cliques can partly complement mapping between genotype and phenotype, and provide clues for understanding the pathogenesis of serious diseases.

  4. SFRP5在T2DM患者脂肪、肌肉中的表达及其与胰岛素抵抗的关系%Expression of secreted frizzled related protein 5 in human adipose and muscle tissues and their relation with insulin resistance

    Institute of Scientific and Technical Information of China (English)

    曾令海; 胡文静; 杨刚毅; 李伶; 王亚旭

    2014-01-01

    目的 探讨正常人及初诊2型糖尿病(type 2 diabetes mellitus,T2DM)患者脂肪、肌肉组织中分泌型卷曲相关蛋白5(secreted frizzled-related protein 5,SFRP5)的差异性表达及其与胰岛素抵抗(insulin resistance,IR)的关系.方法 按照1999年WHO的关于糖尿病的诊断标准选取初诊T2DM患者12例,及年龄、性别相匹配的正常人12例.所有研究对象均来自外科腹部择期手术患者,在同样手术条件下获取腹部大网膜脂肪组织和肌肉组织.常规测量体重、身高、腰围、臀围、血压、胰岛素(Fins)、血糖、糖化血红蛋白(HbA1C)、血脂等,计算胰岛素抵抗指数(HOMA-IR)、胰岛素敏感指数(HOMA-β),用QRT-PCR方法和Western印迹方法检测SFRP5在不同人群中的差异性表达及其与IR的关系.结果 ①T2DM组与正常对照组相比,T2DM组收缩压(SBP),甘油三酯(TG),空腹血糖(FPG),糖负荷后2h血糖(2h PG),Fins,稳态模型评价HOMA-IR,HbA1C均升高.②T2DM组脂肪组织中SFRP5 mRNA和蛋白表达高于正常对照组,差异有统计学意义(2.7倍,5.5倍,均P<0.01),但在肌肉组织中差异无统计学意义.③脂肪组织SFRP5 mRNA和蛋白质高于肌肉组织.结论 脂肪组织SFRP5 mRNA和蛋白质表达高于肌肉组织提示脂肪组织可能是SFRP5的主要来源.T2DM组脂肪组织中SFRP5 mRNA和蛋白表达高于正常对照组提示SFRP5可能与IR严重程度相关.%Objective To investigate the change expression levels of secreted frizzled related protein 5 (SFRP5) mRNA and protein in human adipose,and muscle tissues and the relationship between SFRP5 and insulin resistance in different glucose tolerance subjects.Methods Twelve type 2 diabetes mellitus(T2DM) patients and 12 aged and sex-matched healthy control subjects were enrolled.T2DM patients were diagnosed by1999 WHO criterion.Under the same conditions,the omental adipose and muscle tissues from these patients undergoing elective abdominal surgery were obtained

  5. Coat protein-mediated resistance against an Indian isolate of the Cucumber mosaic virus subgroup IB in Nicotiana benthamiana

    Indian Academy of Sciences (India)

    A Srivastava; S K Raj

    2008-06-01

    Coat protein (CP)-mediated resistance against an Indian isolate of the Cucumber mosaic virus (CMV) subgroup IB was demonstrated in transgenic lines of Nicotiana benthamiana through Agrobacterium tumefaciens-mediated transformation. Out of the fourteen independently transformed lines developed, two lines were tested for resistance against CMV by challenge inoculations. The transgenic lines exhibiting complete resistance remained symptomless throughout life and showed reduced or no virus accumulation in their systemic leaves after virus challenge. These lines also showed virus resistance against two closely related strains of CMV. This is the first report of CP-mediated transgenic resistance against a CMV subgroup IB member isolated from India.

  6. Increased Levels of Antinutritional and/or Defense Proteins Reduced the Protein Quality of a Disease-Resistant Soybean Cultivar

    Directory of Open Access Journals (Sweden)

    Daniele O. B. Sousa

    2015-07-01

    Full Text Available The biochemical and nutritional attributes of two soybean (Glycine max (L. Merr. cultivars, one susceptible (Seridó and the other resistant (Seridó-RCH to stem canker, were examined to assess whether the resistance to pathogens was related to levels of antinutritional and/or defense proteins in the plant and subsequently affected the nutritional quality. Lectin, urease, trypsin inhibitor, peroxidase and chitinase activities were higher in the resistant cultivar. Growing rats were fed with isocaloric and isoproteic diets prepared with defatted raw soybean meals. Those on the Seridó-RCH diet showed the worst performance in terms of protein quality indicators. Based on regression analysis, lectin, trypsin inhibitor, peroxidase and chitinase appear to be involved in the resistance trait but also in the poorer nutritional quality of Seridó-RCH. Thus, the development of cultivars for disease resistance may lead to higher concentrations of antinutritional compounds, affecting the quality of soybean seeds. Further research that includes the assessment of more cultivars/genotypes is needed.

  7. Modulation of breast cancer resistance protein mediated atypical multidrug resistance using RNA interference delivered by adenovirus

    Institute of Scientific and Technical Information of China (English)

    LI Wen-tong; ZHOU Geng-yin; WANG Chun-ling; GUO Cheng-hao; SONG Xian-rang; CHI Wei-ling

    2005-01-01

    @@ Clinical multidrug resistance (MDR) of malignancies to many antineoplastic agents is the major obstacle in the successful treatment of cancer. The emergence of breast cancer resistance protein (BCRP), a member of the adenosine triphosphate (ATP) binding cassette (ABC) transporter family, has necessitated the development of antagonists. To overcome the BCRP-mediated atypical MDR, RNA interference (RNAi) delivered by adenovirus targeting BCRP mRNA was used to inhibit the atypical MDR expression by infecting MCF-7/MX100 cell lines with constructed RNAi adenovirus.

  8. Identification of a putative protein profile associated with tamoxifen therapy resistance in breast cancer.

    Science.gov (United States)

    Umar, Arzu; Kang, Hyuk; Timmermans, Annemieke M; Look, Maxime P; Meijer-van Gelder, Marion E; den Bakker, Michael A; Jaitly, Navdeep; Martens, John W M; Luider, Theo M; Foekens, John A; Pasa-Tolić, Ljiljana

    2009-06-01

    Tamoxifen resistance is a major cause of death in patients with recurrent breast cancer. Current clinical factors can correctly predict therapy response in only half of the treated patients. Identification of proteins that are associated with tamoxifen resistance is a first step toward better response prediction and tailored treatment of patients. In the present study we intended to identify putative protein biomarkers indicative of tamoxifen therapy resistance in breast cancer using nano-LC coupled with FTICR MS. Comparative proteome analysis was performed on approximately 5,500 pooled tumor cells (corresponding to approximately 550 ng of protein lysate/analysis) obtained through laser capture microdissection (LCM) from two independently processed data sets (n = 24 and n = 27) containing both tamoxifen therapy-sensitive and therapy-resistant tumors. Peptides and proteins were identified by matching mass and elution time of newly acquired LC-MS features to information in previously generated accurate mass and time tag reference databases. A total of 17,263 unique peptides were identified that corresponded to 2,556 non-redundant proteins identified with > or = 2 peptides. 1,713 overlapping proteins between the two data sets were used for further analysis. Comparative proteome analysis revealed 100 putatively differentially abundant proteins between tamoxifen-sensitive and tamoxifen-resistant tumors. The presence and relative abundance for 47 differentially abundant proteins were verified by targeted nano-LC-MS/MS in a selection of unpooled, non-microdissected discovery set tumor tissue extracts. ENPP1, EIF3E, and GNB4 were significantly associated with progression-free survival upon tamoxifen treatment for recurrent disease. Differential abundance of our top discriminating protein, extracellular matrix metalloproteinase inducer, was validated by tissue microarray in an independent patient cohort (n = 156). Extracellular matrix metalloproteinase inducer levels were

  9. Diagnostic criteria for sarcopenia relate differently to insulin resistance

    OpenAIRE

    Bijlsma, A. Y.; Meskers, C. G. M.; van Heemst, D.; Westendorp, R. G. J.; de Craen, A. J. M.; Maier, A. B.

    2013-01-01

    Skeletal muscle is important in insulin-stimulated glucose uptake. Sarcopenia is, therefore, a possible risk factor for insulin resistance. Currently, different diagnostic criteria for sarcopenia include low muscle mass, muscle strength, and walking speed. We assessed these muscle characteristics in relation to insulin resistance in nondiabetics. This cross-sectional study included 301 nondiabetics, mean age 65.9 years. Area under curve (AUC) calculations of insulin and glucose from a 2-h ora...

  10. Systemic resistance in Arabidopsis induced by biocontrol bacteria is independent of salicylic acid accumulation and pathogenesis-related gene expression

    NARCIS (Netherlands)

    Pieterse, C.M.J.; Wees, A.C.M. van; Hoffland, E.; Pelt, J.A. van; Loon, L.C. van

    1996-01-01

    Systemic acquired resistance is a pathogen-inducible defense mechanism in plants. The resistant state is dependent on endogenous accumulation of salicylic acid (SA) and is characterized by the activation of genes encoding pathogenesis-related (PR) proteins. Recently, selected nonpathogenic, root-col

  11. Response-reinforcer relations and resistance to change.

    Science.gov (United States)

    Podlesnik, Christopher A; Shahan, Timothy A

    2008-01-01

    Behavioral momentum theory suggests that the relation between a response and a reinforcer (i.e., response-reinforcer relation) governs response rates and the relation between a stimulus and a reinforcer (i.e., stimulus-reinforcer relation) governs resistance to change. The present experiments compared the effects degrading response-reinforcer relations with response-independent or delayed reinforcers on resistance to change in conditions with equal stimulus-reinforcer relations. In Experiment 1, pigeons responded on equal variable-interval schedules of immediate reinforcement in three components of a multiple schedule. Additional response-independent reinforcers were available in one component and additional delayed reinforcers were available in another component. The results showed that resistance to disruption was greater in the components with added reinforcers than without them (i.e., better stimulus-reinforcer relations), but did not differ for the components with added response-independent and delayed reinforcement. In Experiment 2, a component presenting immediate reinforcement alternated with either a component that arranged equal rates of reinforcement with a proportion of those reinforcers being response independent or a component with a proportion of the reinforcers being delayed. Results showed that resistance to disruption tended to be either similar across components or slightly lower when response-reinforcer relations were degraded with either response-independent or delayed reinforcers. These findings suggest that degrading response-reinforcer relations can impact resistance to change, but that impact does not depend on the specific method and is small relative to the effects of the stimulus-reinforcer relation.

  12. Genome-wide association study of drought-related resistance traits in Aegilops tauschii

    Science.gov (United States)

    Qin, Peng; Lin, Yu; Hu, Yaodong; Liu, Kun; Mao, Shuangshuang; Li, Zhanyi; Wang, Jirui; Liu, Yaxi; Wei, Yuming; Zheng, Youliang

    2016-01-01

    Abstract The D-genome progenitor of wheat (Triticum aestivum), Aegilops tauschii, possesses numerous genes for resistance to abiotic stresses, including drought. Therefore, information on the genetic architecture of A. tauschii can aid the development of drought-resistant wheat varieties. Here, we evaluated 13 traits in 373 A. tauschii accessions grown under normal and polyethylene glycol-simulated drought stress conditions and performed a genome-wide association study using 7,185 single nucleotide polymorphism (SNP) markers. We identified 208 and 28 SNPs associated with all traits using the general linear model and mixed linear model, respectively, while both models detected 25 significant SNPs with genome-wide distribution. Public database searches revealed several candidate/flanking genes related to drought resistance that were grouped into three categories according to the type of encoded protein (enzyme, storage protein, and drought-induced protein). This study provided essential information for SNPs and genes related to drought resistance in A. tauschii and wheat, and represents a foundation for breeding drought-resistant wheat cultivars using marker-assisted selection. PMID:27560650

  13. Molecular basis of glyphosate resistance: Different approaches through protein engineering

    Science.gov (United States)

    Pollegioni, Loredano; Schonbrunn, Ernst; Siehl, Daniel

    2011-01-01

    Glyphosate (N-phosphonomethyl-glycine) is the most-used herbicide in the world: glyphosate-based formulations exhibit broad-spectrum herbicidal activity with minimal human and environmental toxicity. The extraordinary success of this simple small molecule is mainly due to the high specificity of glyphosate towards the plant enzyme enolpyruvylshikimate-3-phosphate synthase in the shikimate pathway leading to biosynthesis of aromatic amino acids. Starting in 1996, transgenic glyphosate-resistant plants were introduced thus allowing the application of the herbicide to the crop (post-emergence) to remove emerged weeds without crop damage. This review focuses on the evolution of mechanisms of resistance to glyphosate as obtained through natural diversity, the gene shuffling approach to molecular evolution, and a rational, structure-based approach to protein engineering. In addition, we offer rationale for the means by which the modifications made have had their intended effect. PMID:21668647

  14. Identification of a protein which differs in lines of barley resistant or susceptible to Erysiphe graminis f. sp. hordei

    Energy Technology Data Exchange (ETDEWEB)

    Simons, S.P.; Somerville, S.C. (Michigan State Univ., East Lansing (USA))

    1990-05-01

    As yet no resistance genes or gene products have been isolated from a plant. We wish to isolate the Ml-a gene which encodes resistance by barley to Erysiphe graminis f. sp. hordei, the causal agent of the powdery mildew disease. We have utilized near isogenic barley lines, resistant and susceptible to E. g. hordei, race CR3 to provide a homogenous background for examination of protein differences related to resistance. To enrich for epidermal tissue, the site of infection, proteins from {sup 35}S labelled coleoptiles were analyzed by 2D-PAGE. Two major protein differences were observed, one of which is a polymorphism identified by a higher molecular weight form in the susceptible line, with the lower molecular weight form appearing in the resistant line. A partially susceptible mutant line derived from the resistant line shows a 63% reduction in the level of the resistant form of the polypeptide. A likely conclusion from these results is that we have identified the Ml-a gene product. Further characterization of the polymorphic protein and its gene will lead to an understanding of gene-for-gene related resistance processes.

  15. The expression and significance of P-glycoprotein, lung resistance protein and multidrug resistance-associated protein in gastric cancer

    Directory of Open Access Journals (Sweden)

    Li Yan

    2009-11-01

    Full Text Available Abstract Background To detect the expression of multidrug resistance molecules P-glycoprotein (P-gp, Lung resistnce protein (LRP and Multidrug resistance-associated protein (MRP and analyze the relationship between them and the clinico-pathological features. Methods The expressions of P-gp, LRP and MRP in formalin-fixed paraffin-embedded tissue sections from 59 gastric cancer patients were determined by a labbelled Streptavidin-Peroxidase (SP immunohistochemical technique, and the results were analyzed in correlation with clinicopathological data. None of these patients received chemotherapy prior to surgery. Results The positive rates of P-gp, LRP, MRP were 86.4%, 84.7% and 27.1%, respectively. The difference between the positive rate of P-gp and MRP was significant statistically, as well as the difference between the expression of MRP and LRP. No significant difference was observed between P-gp and LRP, but the positively correlation between the expression of P-gp and LRP had been found. No significant correlation between the expression of P-gp, LRP, MRP and the grade of differentiation were observed. The expression of P-gp was correlated with clinical stages positively (r = 0.742, but the difference with the expression of P-gp in different stages was not significant. Conclusion The expressions of P-gp, LRP and MRP in patients with gastric cancer without prior chemotherapy are high, indicating that innate drug resistance may exist in gastric cancer.

  16. Activated protein C resistance testing for factor V Leiden.

    Science.gov (United States)

    Kadauke, Stephan; Khor, Bernard; Van Cott, Elizabeth M

    2014-12-01

    Activated protein C resistance assays can detect factor V Leiden with high accuracy, depending on the method used. Factor Xa inhibitors such as rivaroxaban and direct thrombin inhibitors including dabigatran, argatroban, and bivalirudin can cause falsely normal results. Lupus anticoagulants can cause incorrect results in most current assays. Assays that include dilution into factor V-deficient plasma are needed to avoid interference from factor deficiencies or elevations, which can arise from a wide variety of conditions such as warfarin, liver dysfunction, or pregnancy. The pros and cons of the currently available assays are discussed. © 2014 Wiley Periodicals, Inc.

  17. Antibiotic Resistance Related to Biofilm Formation in Klebsiella pneumoniae

    Directory of Open Access Journals (Sweden)

    Claudia Vuotto

    2014-09-01

    Full Text Available The Gram-negative opportunistic pathogen, Klebsiella pneumoniae, is responsible for causing a spectrum of community-acquired and nosocomial infections and typically infects patients with indwelling medical devices, especially urinary catheters, on which this microorganism is able to grow as a biofilm. The increasingly frequent acquisition of antibiotic resistance by K. pneumoniae strains has given rise to a global spread of this multidrug-resistant pathogen, mostly at the hospital level. This scenario is exacerbated when it is noted that intrinsic resistance to antimicrobial agents dramatically increases when K. pneumoniae strains grow as a biofilm. This review will summarize the findings about the antibiotic resistance related to biofilm formation in K. pneumoniae.

  18. Bioinformatics and structural characterization of a hypothetical protein from Streptococcus mutans: implication of antibiotic resistance.

    Directory of Open Access Journals (Sweden)

    Jie Nan

    Full Text Available As an oral bacterial pathogen, Streptococcus mutans has been known as the aetiologic agent of human dental caries. Among a total of 1960 identified proteins within the genome of this organism, there are about 500 without any known functions. One of these proteins, SMU.440, has very few homologs in the current protein databases and it does not fall into any protein functional families. Phylogenetic studies showed that SMU.440 is related to a particular ecological niche and conserved specifically in some oral pathogens, due to lateral gene transfer. The co-occurrence of a MarR protein within the same operon among these oral pathogens suggests that SMU.440 may be associated with antibiotic resistance. The structure determination of SMU.440 revealed that it shares the same fold and a similar pocket as polyketide cyclases, which indicated that it is very likely to bind some polyketide-like molecules. From the interlinking structural and bioinformatics studies, we have concluded that SMU.440 could be involved in polyketide-like antibiotic resistance, providing a better understanding of this hypothetical protein. Besides, the combination of multiple methods in this study can be used as a general approach for functional studies of a protein with unknown function.

  19. The relative nutritive value of lucerne leaf protein concentrate (LPC ...

    African Journals Online (AJOL)

    measure of response to dietary protein and lactalbumin was .... fed ad libitum from 28 to 49 days of age whereafter the rats ... protein was related to protein intake according to the same .... composition of young obese and lean Zucker rats.

  20. Antimicrobial resistance and related issues: An overview of Bangladesh situation

    Directory of Open Access Journals (Sweden)

    Md. Sayedur Rahman

    2014-06-01

    Full Text Available The present study was designed to understand Bangladesh situation about antimicrobial resistance. Half of the Escherichia coli, Staphylococcus aureus, Pseudomonas and Klebsiella showed resistance against older and common antimicrobials. Most (50% common reasons to prescribe antimicrobial are fever, respiratory and urinary tract infection. About 70% prescriber mentioned diagnostic uncertainty and emergence of resistance as causes for increase in antimicrobial prescribing. 51.9% of prescribers opined that physicians prescribe antimicrobial more than the actual need. About two-third of 5th year medical students answered correctly on different issues related to antimicrobials and resistance. Antimicrobial and resistance received little emphasis in Pharmacology and Microbiology written questions at both undergraduate (0.7 to 16.1% and postgraduate (0.9 to 18.4% level. Print (0.02% to 2.0% and electronic media (0.0 to 0.6% attaches small importance on the issues. Nothing related to ‘antimicrobials’ and ‘measure to contain resistance’ were mentioned in related policy documents.

  1. The role of breast cancer resistance protein in acute lymphoblastic leukemia

    NARCIS (Netherlands)

    Plasschaert, SLA; van der Kolk, D.M.; de Bout, ESJM; Kamps, WA; Morisaki, K; Bates, SE; Scheffer, GL; Scheper, RJ; Vellenga, E; de Vries, EGE

    2003-01-01

    Purpose: Overexpression of the transporter ABCG2, also known as breast cancer resistance protein and mitoxantrone resistance protein, can confer resistance to a variety of cytostatic drugs, such as mitoxantrone, topotecan, doxorubicin, and daunorubicin. This study analyzes the ABCG2 expression and a

  2. Protein function prediction using neighbor relativity in protein-protein interaction network.

    Science.gov (United States)

    Moosavi, Sobhan; Rahgozar, Masoud; Rahimi, Amir

    2013-04-01

    There is a large gap between the number of discovered proteins and the number of functionally annotated ones. Due to the high cost of determining protein function by wet-lab research, function prediction has become a major task for computational biology and bioinformatics. Some researches utilize the proteins interaction information to predict function for un-annotated proteins. In this paper, we propose a novel approach called "Neighbor Relativity Coefficient" (NRC) based on interaction network topology which estimates the functional similarity between two proteins. NRC is calculated for each pair of proteins based on their graph-based features including distance, common neighbors and the number of paths between them. In order to ascribe function to an un-annotated protein, NRC estimates a weight for each neighbor to transfer its annotation to the unknown protein. Finally, the unknown protein will be annotated by the top score transferred functions. We also investigate the effect of using different coefficients for various types of functions. The proposed method has been evaluated on Saccharomyces cerevisiae and Homo sapiens interaction networks. The performance analysis demonstrates that NRC yields better results in comparison with previous protein function prediction approaches that utilize interaction network. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Combinatorial synthesis with high throughput discovery of protein-resistant membrane surfaces.

    Science.gov (United States)

    Gu, Minghao; Vegas, Arturo J; Anderson, Daniel G; Langer, Robert S; Kilduff, James E; Belfort, Georges

    2013-08-01

    Using combinatorial methods, we synthesized a series of new vinyl amide monomers and graft-polymerized them to light-sensitive poly(ether sulfone) (PES) porous films for protein resistance. To increase the discovery rate and statistical confidence, we developed high throughput surface modification methods (HTP) that allow synthesis, screening and selection of desirable monomers from a large library in a relatively short time (days). A series of amide monomers were synthesized by amidation of methacryloyl chloride with amines and grafted onto commercial poly(ether sulfone) (PES) membranes using irradiation from atmospheric pressure plasma (APP). The modified PES membrane surfaces were then tested and screened for static protein adhesion using HTP. Hydroxyl amide monomers N-(3-hydroxypropyl)methacrylamide (A3), N-(4-hydroxybutyl)methacrylamide (A4), and N-(4-hydroxybutyl)methacrylamide (A6), ethylene glycol (EG) monomer N-(3-methoxypropyl)methacrylamide (A7), and N-(2-(dimethylamino)ethyl)-N-methylmethacrylamide (A8), and N-(2-(diethylamino)ethyl)-N-methylmethacrylamide (A9) all terminated with tertiary amines and were shown to have protein resistance. The PES membranes modified with these monomers exhibited both low protein adhesion (i.e. membrane plugging or fouling) and high flux. Their performance is comparable with previously identified best performing PEG and zwitterionic monomers, i.e. the so-called gold-standard for protein resistance. Combining a Hansen solubility parameter (HSP) analysis of the amide monomers and the HTP filtration results, we conclude that monomer solubility in water correlates with protein-resistant surfaces, presumably through its effects on surface-water interactions.

  4. Mutation in ribosomal protein S5 leads to spectinomycin resistance in Neisseria gonorrhoeae.

    Directory of Open Access Journals (Sweden)

    Elena eIlina

    2013-07-01

    Full Text Available Spectinomycin remains a useful reserve option for therapy of gonorrhea. The emergence of multidrug-resistant Neisseria gonorrhoeae strains with decreased susceptibility to cefixime and to ceftriaxone makes it the only medicine still effective for treatment of gonorrhea infection in analogous cases. However, adoption of spectinomycin as a routinely used drug of choice was soon followed by reports of spectinomycin resistance. The main molecular mechanism of spectinomycin resistance in N. gonorrhoeae was C1192T substitution in 16S rRNA genes. Here we reported a Thr-24→Pro mutation in ribosomal protein S5 found in spectinomycin resistant clinical N. gonorrhoeae strain, which carried no changes in 16S rRNA. In a series of experiments, the transfer of rpsE gene allele encoding the mutant ribosomal protein S5 to the recipient N. gonorrhoeae strains was analyzed. The relatively high rate of transformation (ca. 10-5 CFUs indicates the possibility of spread of spectinonycin resistance within gonococcal population due to the horizontal gene transfer.

  5. TgPRELID, a Mitochondrial Protein Linked to Multidrug Resistance in the Parasite Toxoplasma gondii

    Science.gov (United States)

    Kamau, Edwin T.; Srinivasan, Ananth R.; Harper, Jonathan; Sankaran, Preethi; Post, Sarah E.; Varberg, Joseph M.

    2017-01-01

    ABSTRACT New drugs to control infection with the protozoan parasite Toxoplasma gondii are needed as current treatments exert toxic side effects on patients. Approaches to develop novel compounds for drug development include screening of compound libraries and targeted inhibition of essential cellular pathways. We identified two distinct compounds that display inhibitory activity against the parasite’s replicative stage: F3215-0002, which we previously identified during a compound library screen, and I-BET151, an inhibitor of bromodomains, the “reader” module of acetylated lysines. In independent studies, we sought to determine the targets of these two compounds using forward genetics, generating resistant mutants and identifying the determinants of resistance with comparative genome sequencing. Despite the dissimilarity of the two compounds, we recovered resistant mutants with nonsynonymous mutations in the same domain of the same gene, TGGT1_254250, which we found encodes a protein that localizes to the parasite mitochondrion (designated TgPRELID after the name of said domain). We found that mutants selected with one compound were cross resistant to the other compound, suggesting a common mechanism of resistance. To further support our hypothesis that TgPRELID mutations facilitate resistance to both I-BET151 and F3215-0002, CRISPR (clustered regularly interspaced short palindromic repeat)/CAS9-mediated mutation of TgPRELID directly led to increased F3215-0002 resistance. Finally, all resistance mutations clustered in the same subdomain of TgPRELID. These findings suggest that TgPRELID may encode a multidrug resistance factor or that I-BET151 and F3215-0002 have the same target(s) despite their distinct chemical structures. IMPORTANCE We report the discovery of TgPRELID, a previously uncharacterized mitochondrial protein linked to multidrug resistance in the parasite Toxoplasma gondii. Drug resistance remains a major problem in the battle against parasitic

  6. A Lipid Transfer Protein Increases the Glutathione Content and Enhances Arabidopsis Resistance to a Trichothecene Mycotoxin.

    Directory of Open Access Journals (Sweden)

    John E McLaughlin

    Full Text Available Fusarium head blight (FHB or scab is one of the most important plant diseases worldwide, affecting wheat, barley and other small grains. Trichothecene mycotoxins such as deoxynivalenol (DON accumulate in the grain, presenting a food safety risk and health hazard to humans and animals. Despite considerable breeding efforts, highly resistant wheat or barley cultivars are not available. We screened an activation tagged Arabidopsis thaliana population for resistance to trichothecin (Tcin, a type B trichothecene in the same class as DON. Here we show that one of the resistant lines identified, trichothecene resistant 1 (trr1 contains a T-DNA insertion upstream of two nonspecific lipid transfer protein (nsLTP genes, AtLTP4.4 and AtLTP4.5. Expression of both nsLTP genes was induced in trr1 over 10-fold relative to wild type. Overexpression of AtLTP4.4 provided greater resistance to Tcin than AtLTP4.5 in Arabidopsis thaliana and in Saccharomyces cerevisiae relative to wild type or vector transformed lines, suggesting a conserved protection mechanism. Tcin treatment increased reactive oxygen species (ROS production in Arabidopsis and ROS stain was associated with the chloroplast, the cell wall and the apoplast. ROS levels were attenuated in Arabidopsis and in yeast overexpressing AtLTP4.4 relative to the controls. Exogenous addition of glutathione and other antioxidants enhanced resistance of Arabidopsis to Tcin while the addition of buthionine sulfoximine, an inhibitor of glutathione synthesis, increased sensitivity, suggesting that resistance was mediated by glutathione. Total glutathione content was significantly higher in Arabidopsis and in yeast overexpressing AtLTP4.4 relative to the controls, highlighting the importance of AtLTP4.4 in maintaining the redox state. These results demonstrate that trichothecenes cause ROS accumulation and overexpression of AtLTP4.4 protects against trichothecene-induced oxidative stress by increasing the glutathione

  7. A Lipid Transfer Protein Increases the Glutathione Content and Enhances Arabidopsis Resistance to a Trichothecene Mycotoxin.

    Science.gov (United States)

    McLaughlin, John E; Bin-Umer, Mohamed Anwar; Widiez, Thomas; Finn, Daniel; McCormick, Susan; Tumer, Nilgun E

    2015-01-01

    Fusarium head blight (FHB) or scab is one of the most important plant diseases worldwide, affecting wheat, barley and other small grains. Trichothecene mycotoxins such as deoxynivalenol (DON) accumulate in the grain, presenting a food safety risk and health hazard to humans and animals. Despite considerable breeding efforts, highly resistant wheat or barley cultivars are not available. We screened an activation tagged Arabidopsis thaliana population for resistance to trichothecin (Tcin), a type B trichothecene in the same class as DON. Here we show that one of the resistant lines identified, trichothecene resistant 1 (trr1) contains a T-DNA insertion upstream of two nonspecific lipid transfer protein (nsLTP) genes, AtLTP4.4 and AtLTP4.5. Expression of both nsLTP genes was induced in trr1 over 10-fold relative to wild type. Overexpression of AtLTP4.4 provided greater resistance to Tcin than AtLTP4.5 in Arabidopsis thaliana and in Saccharomyces cerevisiae relative to wild type or vector transformed lines, suggesting a conserved protection mechanism. Tcin treatment increased reactive oxygen species (ROS) production in Arabidopsis and ROS stain was associated with the chloroplast, the cell wall and the apoplast. ROS levels were attenuated in Arabidopsis and in yeast overexpressing AtLTP4.4 relative to the controls. Exogenous addition of glutathione and other antioxidants enhanced resistance of Arabidopsis to Tcin while the addition of buthionine sulfoximine, an inhibitor of glutathione synthesis, increased sensitivity, suggesting that resistance was mediated by glutathione. Total glutathione content was significantly higher in Arabidopsis and in yeast overexpressing AtLTP4.4 relative to the controls, highlighting the importance of AtLTP4.4 in maintaining the redox state. These results demonstrate that trichothecenes cause ROS accumulation and overexpression of AtLTP4.4 protects against trichothecene-induced oxidative stress by increasing the glutathione

  8. Comparisons of protein profiles of beech bark disease resistant and susceptible American beech (Fagus grandifolia

    Directory of Open Access Journals (Sweden)

    Mason Mary E

    2013-01-01

    Full Text Available Abstract Background Beech bark disease is an insect-fungus complex that damages and often kills American beech trees and has major ecological and economic impacts on forests of the northeastern United States and southeastern Canadian forests. The disease begins when exotic beech scale insects feed on the bark of trees, and is followed by infection of damaged bark tissues by one of the Neonectria species of fungi. Proteomic analysis was conducted of beech bark proteins from diseased trees and healthy trees in areas heavily infested with beech bark disease. All of the diseased trees had signs of Neonectria infection such as cankers or fruiting bodies. In previous tests reported elsewhere, all of the diseased trees were demonstrated to be susceptible to the scale insect and all of the healthy trees were demonstrated to be resistant to the scale insect. Sixteen trees were sampled from eight geographically isolated stands, the sample consisting of 10 healthy (scale-resistant and 6 diseased/infested (scale-susceptible trees. Results Proteins were extracted from each tree and analysed in triplicate by isoelectric focusing followed by denaturing gel electrophoresis. Gels were stained and protein spots identified and intensity quantified, then a statistical model was fit to identify significant differences between trees. A subset of BBD differential proteins were analysed by mass spectrometry and matched to known protein sequences for identification. Identified proteins had homology to stress, insect, and pathogen related proteins in other plant systems. Protein spots significantly different in diseased and healthy trees having no stand or disease-by-stand interaction effects were identified. Conclusions Further study of these proteins should help to understand processes critical to resistance to beech bark disease and to develop biomarkers for use in tree breeding programs and for the selection of resistant trees prior to or in early stages of BBD

  9. Protease-resistant prions selectively decrease Shadoo protein.

    Directory of Open Access Journals (Sweden)

    Joel C Watts

    2011-11-01

    Full Text Available The central event in prion diseases is the conformational conversion of the cellular prion protein (PrP(C into PrP(Sc, a partially protease-resistant and infectious conformer. However, the mechanism by which PrP(Sc causes neuronal dysfunction remains poorly understood. Levels of Shadoo (Sho, a protein that resembles the flexibly disordered N-terminal domain of PrP(C, were found to be reduced in the brains of mice infected with the RML strain of prions [1], implying that Sho levels may reflect the presence of PrP(Sc in the brain. To test this hypothesis, we examined levels of Sho during prion infection using a variety of experimental systems. Sho protein levels were decreased in the brains of mice, hamsters, voles, and sheep infected with different natural and experimental prion strains. Furthermore, Sho levels were decreased in the brains of prion-infected, transgenic mice overexpressing Sho and in infected neuroblastoma cells. Time-course experiments revealed that Sho levels were inversely proportional to levels of protease-resistant PrP(Sc. Membrane anchoring and the N-terminal domain of PrP both influenced the inverse relationship between Sho and PrP(Sc. Although increased Sho levels had no discernible effect on prion replication in mice, we conclude that Sho is the first non-PrP marker specific for prion disease. Additional studies using this paradigm may provide insight into the cellular pathways and systems subverted by PrP(Sc during prion disease.

  10. Heat shock protein 90 and its co-chaperone protein phosphatase 5 interact with distinct regions of the tomato I-2 disease resistance protein

    NARCIS (Netherlands)

    de la Fuente van Bentem, S.; Vossen, J.H.; de Vries, K.J.; van Wees, A.C.M.; Tameling, W.I.L.; Dekker, H.L.; de Koster, C.G.; Haring, M.A.; Takken, F.L.W.; Cornelissen, B.J.C.

    2005-01-01

    Recent data suggest that plant disease resistance (R) proteins are present in multi-protein complexes. Tomato R protein I-2 confers resistance against the fungal pathogen Fusarium oxysporum. To identify components of the I-2 complex, we performed yeast two-hybrid screens using the I-2 leucine-rich

  11. Website on Protein Interaction and Protein Structure Related Work

    Science.gov (United States)

    Samanta, Manoj; Liang, Shoudan; Biegel, Bryan (Technical Monitor)

    2003-01-01

    In today's world, three seemingly diverse fields - computer information technology, nanotechnology and biotechnology are joining forces to enlarge our scientific knowledge and solve complex technological problems. Our group is dedicated to conduct theoretical research exploring the challenges in this area. The major areas of research include: 1) Yeast Protein Interactions; 2) Protein Structures; and 3) Current Transport through Small Molecules.

  12. Positive muscle protein net balance and differential regulation of atrogene expression after resistance exercise and milk protein supplementation

    DEFF Research Database (Denmark)

    Reitelseder, Søren; Agergaard, Jakob; Doessing, Simon

    2014-01-01

    Purpose Resistance exercise and amino acid availability are positive regulators of muscle protein net balance (NB). However, anabolic responses to resistance exercise and protein supplementation deserve further elucidation. The purpose was to compare intakes of whey, caseinate (both: 0.30 g/kg le......RNA expressions indicate different regulatory mechanisms on the ubiquitin ligases MuRF1 and Atrogin1 in recovery from heavy resistance exercise....

  13. SynProt: A Database for Proteins of Detergent-Resistant Synaptic Protein Preparations

    Science.gov (United States)

    Pielot, Rainer; Smalla, Karl-Heinz; Müller, Anke; Landgraf, Peter; Lehmann, Anne-Christin; Eisenschmidt, Elke; Haus, Utz-Uwe; Weismantel, Robert; Gundelfinger, Eckart D.; Dieterich, Daniela C.

    2012-01-01

    Chemical synapses are highly specialized cell–cell contacts for communication between neurons in the CNS characterized by complex and dynamic protein networks at both synaptic membranes. The cytomatrix at the active zone (CAZ) organizes the apparatus for the regulated release of transmitters from the presynapse. At the postsynaptic side, the postsynaptic density constitutes the machinery for detection, integration, and transduction of the transmitter signal. Both pre- and postsynaptic protein networks represent the molecular substrates for synaptic plasticity. Their function can be altered both by regulating their composition and by post-translational modification of their components. For a comprehensive understanding of synaptic networks the entire ensemble of synaptic proteins has to be considered. To support this, we established a comprehensive database for synaptic junction proteins (SynProt database) primarily based on proteomics data obtained from biochemical preparations of detergent-resistant synaptic junctions. The database currently contains 2,788 non-redundant entries of rat, mouse, and some human proteins, which mainly have been manually extracted from 12 proteomic studies and annotated for synaptic subcellular localization. Each dataset is completed with manually added information including protein classifiers as well as automatically retrieved and updated information from public databases (UniProt and PubMed). We intend that the database will be used to support modeling of synaptic protein networks and rational experimental design. PMID:22737123

  14. Parathyroid hormone-related protein: an update.

    Science.gov (United States)

    Wysolmerski, John J

    2012-09-01

    PTHrP was identified as a cause of hypercalcemia in cancer patients 25 yr ago. In the intervening years, we have learned that PTHrP and PTH are encoded by related genes that are part of a larger "PTH gene family." This evolutionary relationship permits them to bind to the same type 1 PTH/PTHrP receptor, which explains why humoral hypercalcemia of malignancy resembles hyperparathyroidism. This review will outline basic facts about PTHrP biology and its normal physiological functions, with an emphasis on new findings of the past 5-10 yr. The medical and research communities first became aware of PTHrP because of its involvement in a common paraneoplastic syndrome. Now, research into the basic biology of PTHrP has suggested previously unrecognized connections to a variety of disease states such as osteoporosis, osteoarthritis, and breast cancer and has highlighted how PTHrP itself might be used in therapy for osteoporosis and diabetes. Therefore, the story of this remarkable protein is a paradigm for translational research, having gone from bedside to bench and now back to bedside.

  15. Theoretical model of the three-dimensional structure of a disease resistance gene homolog encoding resistance protein in Vigna mungo.

    Science.gov (United States)

    Basak, Jolly; Bahadur, Ranjit P

    2006-10-01

    Plant disease resistance (R) genes, the key players of innate immunity system in plants encode 'R' proteins. 'R' protein recognizes product of avirulance gene from the pathogen and activate downstream signaling responses leading to disease resistance. No three dimensional (3D) structural information of any 'R' proteins is available as yet. We have reported a 'R' gene homolog, the 'VMYR1', encoding 'R' protein in Vigna mungo. Here, we describe the homology modeling of the 'VMYR1' protein. The model was created by using the 3D structure of an ATP-binding cassette transporter protein from Vibrio cholerae as a template. The strategy for homology modeling was based on the high structural conservation in the superfamily of P-loop containing nucleoside triphosphate hydrolase in which target and template proteins belong. This is the first report of theoretical model structure of any 'R' proteins.

  16. p53 protein aggregation promotes platinum resistance in ovarian cancer.

    Science.gov (United States)

    Yang-Hartwich, Y; Soteras, M G; Lin, Z P; Holmberg, J; Sumi, N; Craveiro, V; Liang, M; Romanoff, E; Bingham, J; Garofalo, F; Alvero, A; Mor, G

    2015-07-01

    High-grade serous ovarian carcinoma (HGSOC), the most lethal gynecological cancer, often leads to chemoresistant diseases. The p53 protein is a key transcriptional factor regulating cellular homeostasis. A majority of HGSOCs have inactive p53 because of genetic mutations. However, genetic mutation is not the only cause of p53 inactivation. The aggregation of p53 protein has been discovered in different types of cancers and may be responsible for impairing the normal transcriptional activation and pro-apoptotic functions of p53. We demonstrated that in a unique population of HGSOC cancer cells with cancer stem cell properties, p53 protein aggregation is associated with p53 inactivation and platinum resistance. When these cancer stem cells differentiated into their chemosensitive progeny, they lost tumor-initiating capacity and p53 aggregates. In addition to the association of p53 aggregation and chemoresistance in HGSOC cells, we further demonstrated that the overexpression of a p53-positive regulator, p14ARF, inhibited MDM2-mediated p53 degradation and led to the imbalance of p53 turnover that promoted the formation of p53 aggregates. With in vitro and in vivo models, we demonstrated that the inhibition of p14ARF could suppress p53 aggregation and sensitize cancer cells to platinum treatment. Moreover, by two-dimensional gel electrophoresis and mass spectrometry we discovered that the aggregated p53 may function uniquely by interacting with proteins that are critical for cancer cell survival and tumor progression. Our findings help us understand the poor chemoresponse of a subset of HGSOC patients and suggest p53 aggregation as a new marker for chemoresistance. Our findings also suggest that inhibiting p53 aggregation can reactivate p53 pro-apoptotic function. Therefore, p53 aggregation is a potential therapeutic target for reversing chemoresistance. This is paramount for improving ovarian cancer patients' responses to chemotherapy, and thus increasing their

  17. Modelling proteins' hidden conformations to predict antibiotic resistance

    Science.gov (United States)

    Hart, Kathryn M.; Ho, Chris M. W.; Dutta, Supratik; Gross, Michael L.; Bowman, Gregory R.

    2016-10-01

    TEM β-lactamase confers bacteria with resistance to many antibiotics and rapidly evolves activity against new drugs. However, functional changes are not easily explained by differences in crystal structures. We employ Markov state models to identify hidden conformations and explore their role in determining TEM's specificity. We integrate these models with existing drug-design tools to create a new technique, called Boltzmann docking, which better predicts TEM specificity by accounting for conformational heterogeneity. Using our MSMs, we identify hidden states whose populations correlate with activity against cefotaxime. To experimentally detect our predicted hidden states, we use rapid mass spectrometric footprinting and confirm our models' prediction that increased cefotaxime activity correlates with reduced Ω-loop flexibility. Finally, we design novel variants to stabilize the hidden cefotaximase states, and find their populations predict activity against cefotaxime in vitro and in vivo. Therefore, we expect this framework to have numerous applications in drug and protein design.

  18. Oxysterol-related-binding-protein related Protein-2 (ORP2) regulates cortisol biosynthesis and cholesterol homeostasis.

    Science.gov (United States)

    Escajadillo, Tamara; Wang, Hongxia; Li, Linda; Li, Donghui; Sewer, Marion B

    2016-05-15

    Oxysterol binding protein-related protein 2 (ORP2) is a lipid binding protein that has been implicated in various cellular processes, including lipid sensing, cholesterol efflux, and endocytosis. We recently identified ORP2 as a member of a protein complex that regulates glucocorticoid biosynthesis. Herein, we examine the effect of silencing ORP2 on adrenocortical function and show that the ORP2 knockdown cells exhibit reduced amounts of multiple steroid metabolites, including progesterone, 11-deoxycortisol, and cortisol, but have increased concentrations of androgens, and estrogens. Moreover, silencing ORP2 suppresses the expression of most proteins required for cortisol production and reduces the expression of steroidogenic factor 1 (SF1). ORP2 silencing also increases cellular cholesterol, concomitant with decreased amounts of 22-hydroxycholesterol and 7-ketocholesterol, two molecules that have been shown to bind to ORP2. Further, we show that ORP2 binds to liver X receptor (LXR) and is required for nuclear LXR expression. LXR and ORP2 are recruited to the CYP11B1 promoter in response to cAMP signaling. Additionally, ORP2 is required for the expression of other LXR target genes, including ABCA1 and the LDL receptor (LDLR). In summary, we establish a novel role for ORP2 in regulating steroidogenic capacity and cholesterol homeostasis in the adrenal cortex.

  19. Proteomic analysis of cell lines to identify the irinotecan resistance proteins

    Indian Academy of Sciences (India)

    Xing-Chen Peng; Feng-Ming Gong; Meng Wei; X I Chen; Y E Chen; K E Cheng; Feng Gao; Feng Xu; FENG Bi; Ji-Yan Liu

    2010-12-01

    Chemotherapeutic drug resistance is a frequent cause of treatment failure in colon cancer patients. Several mechanisms have been implicated in drug resistance. However, they are not sufficient to exhaustively account for this resistance emergence. In this study, two-dimensional gel electrophoresis (2-DE) and the PDQuest software analysis were applied to compare the differential expression of irinotecan-resistance-associated protein in human colon adenocarcinoma LoVo cells and irinotecan-resistant LoVo cells (LoVo/irinotecan). The differential protein dots were excised and analysed by ESI-Q-TOF mass spectrometry (MS). Fifteen proteins were identified, including eight proteins with decreased expression and seven proteins with increased expression. The identified known proteins included those that function in diverse biological processes such as cellular transcription, cell apoptosis, electron transport/redox regulation, cell proliferation/differentiation and retinol metabolism pathways. Identification of such proteins could allow improved understanding of the mechanisms leading to the acquisition of chemoresistance.

  20. Increased chitin biosynthesis contributes to the resistance of Penicillium polonicum against the antifungal protein PgAFP.

    Science.gov (United States)

    Delgado, Josué; Owens, Rebecca A; Doyle, Sean; Asensio, Miguel A; Núñez, Félix

    2016-01-01

    Antifungal proteins from molds have been proposed as a valuable tool against unwanted molds, but the resistance of some fungi limits their use. Resistance to antimicrobial peptides has been suggested to be due to lack of interaction with the mold or to a successful response. The antifungal protein PgAFP produced by Penicillium chrysogenum inhibits the growth of various ascomycetes, but not Penicillium polonicum. To study the basis for resistance to this antifungal protein, localization of PgAFP and metabolic, structural, and morphological changes were investigated in P. polonicum. PgAFP bound the outer layer of P. polonicum but not regenerated chitin, suggesting an interaction with specific molecules. Comparative two-dimensional gel electrophoresis (2D-PAGE) and comparative quantitative proteomics revealed changes in the relative abundance of several proteins from ribosome, spliceosome, metabolic, and biosynthesis of secondary metabolite pathways. The proteome changes and an altered permeability reveal an active reaction of P. polonicum to PgAFP. The successful response of the resistant mold seems to be based on the higher abundance of protein Rho GTPase Rho1 that would lead to the increased chitin deposition via cell wall integrity (CWI) signaling pathway. Thus, combined treatment with chitinases could provide a complementary means to combat resistance to antifungal proteins.

  1. Relative resistance index (RRI) - a scoring system for antibiotic resistance in Pseudomonas aeruginosa.

    Science.gov (United States)

    Ewing, J; McCaughan, J; Moore, J; Fairley, D; Sutherland, B; Reid, A; Downey, D

    2017-07-26

    There is a need to measure antibiotic resistance of Pseudomonas aeruginosa (PA) in cystic fibrosis (CF), either qualitatively or quantitatively, to inform patient management. The aim of this study was to develop a simple method by which resistance can be quantified by calculating a relative resistance index (RRI), and to assess correlation of RRIs with clinical variables. In our model, RRIs were calculated based on resistance to aztreonam, ceftazidime, ciprofloxacin, colistin, meropenem, tazocin, temicillin and tobramycin. Eighty-five adults with CF and chronic PA colonisation were identified. For each, all PA cultures were allocated a score of 0 for susceptible, 0.5 for intermediate resistance or 1 for resistance for each antibiotic listed above, and the RRI calculated by dividing the sum of these by the number of antibiotics, giving a maximum score of 1. The mean RRIs for all cultures were correlated with key clinical variables monitored in CF patients (including age, FEV1, IV antibiotic days and BMI). RRIs for non-mucoid PA exhibited moderate positive correlation with total number of IV days (r = 0.405; p < 0.001) and moderate negative correlation with FEV1 % predicted (r = -0.437; p < 0.001). RRIs were not significantly correlated with duration of colonisation, typing (clonal vs other strain) or BMI. Median RRIs were significantly higher for females (0.26, IQR 0.13-0.54) than males (0.18, IQR 0.07-0.37) for non-mucoid PA only (p = 0.03). RRI is an easily calculated measure that correlates with other clinical variables in CF patients and enables quantitative monitoring of resistance.

  2. Significance of inducible defense-related proteins in infected plants

    NARCIS (Netherlands)

    Loon, L.C. van; Rep, M.; Pieterse, C.M.J.

    2006-01-01

    Inducible defense-related proteins have been described in many plant species upon infection with oomycetes, fungi, bacteria, or viruses, or insect attack. Several types of proteins are common and have been classified into 17 families of pathogenesis-related proteins (PRs). Others have so far been fo

  3. Significance of inducible defense-related proteins in infected plants

    NARCIS (Netherlands)

    Loon, L.C. van; Rep, M.; Pieterse, C.M.J.

    2006-01-01

    Inducible defense-related proteins have been described in many plant species upon infection with oomycetes, fungi, bacteria, or viruses, or insect attack. Several types of proteins are common and have been classified into 17 families of pathogenesis-related proteins (PRs). Others have so far been

  4. Significance of inducible defense-related proteins in infected plants

    NARCIS (Netherlands)

    Loon, L.C. van; Rep, M.; Pieterse, C.M.J.

    2006-01-01

    Inducible defense-related proteins have been described in many plant species upon infection with oomycetes, fungi, bacteria, or viruses, or insect attack. Several types of proteins are common and have been classified into 17 families of pathogenesis-related proteins (PRs). Others have so far been fo

  5. ϕX174 Procapsid Assembly: Effects of an Inhibitory External Scaffolding Protein and Resistant Coat Proteins In Vitro.

    Science.gov (United States)

    Cherwa, James E; Tyson, Joshua; Bedwell, Gregory J; Brooke, Dewey; Edwards, Ashton G; Dokland, Terje; Prevelige, Peter E; Fane, Bentley A

    2017-01-01

    During ϕX174 morphogenesis, 240 copies of the external scaffolding protein D organize 12 pentameric assembly intermediates into procapsids, a reaction reconstituted in vitro In previous studies, ϕX174 strains resistant to exogenously expressed dominant lethal D genes were experimentally evolved. Resistance was achieved by the stepwise acquisition of coat protein mutations. Once resistance was established, a stimulatory D protein mutation that greatly increased strain fitness arose. In this study, in vitro biophysical and biochemical methods were utilized to elucidate the mechanistic details and evolutionary trade-offs created by the resistance mutations. The kinetics of procapsid formation was analyzed in vitro using wild-type, inhibitory, and experimentally evolved coat and scaffolding proteins. Our data suggest that viral fitness is correlated with in vitro assembly kinetics and demonstrate that in vivo experimental evolution can be analyzed within an in vitro biophysical context. Experimental evolution is an extremely valuable tool. Comparisons between ancestral and evolved genotypes suggest hypotheses regarding adaptive mechanisms. However, it is not always possible to rigorously test these hypotheses in vivo We applied in vitro biophysical and biochemical methods to elucidate the mechanistic details that allowed an experimentally evolved virus to become resistant to an antiviral protein and then evolve a productive use for that protein. Moreover, our results indicate that the respective roles of scaffolding and coat proteins may have been redistributed during the evolution of a two-scaffolding-protein system. In one-scaffolding-protein virus assembly systems, coat proteins promiscuously interact to form heterogeneous aberrant structures in the absence of scaffolding proteins. Thus, the scaffolding protein controls fidelity. During ϕX174 assembly, the external scaffolding protein acts like a coat protein, self-associating into large aberrant spherical

  6. New noncovalent inhibitors of penicillin-binding proteins from penicillin-resistant bacteria.

    Directory of Open Access Journals (Sweden)

    Samo Turk

    Full Text Available BACKGROUND: Penicillin-binding proteins (PBPs are well known and validated targets for antibacterial therapy. The most important clinically used inhibitors of PBPs β-lactams inhibit transpeptidase activity of PBPs by forming a covalent penicilloyl-enzyme complex that blocks the normal transpeptidation reaction; this finally results in bacterial death. In some resistant bacteria the resistance is acquired by active-site distortion of PBPs, which lowers their acylation efficiency for β-lactams. To address this problem we focused our attention to discovery of novel noncovalent inhibitors of PBPs. METHODOLOGY/PRINCIPAL FINDINGS: Our in-house bank of compounds was screened for inhibition of three PBPs from resistant bacteria: PBP2a from Methicillin-resistant Staphylococcus aureus (MRSA, PBP2x from Streptococcus pneumoniae strain 5204, and PBP5fm from Enterococcus faecium strain D63r. Initial hit inhibitor obtained by screening was then used as a starting point for computational similarity searching for structurally related compounds and several new noncovalent inhibitors were discovered. Two compounds had promising inhibitory activities of both PBP2a and PBP2x 5204, and good in-vitro antibacterial activities against a panel of Gram-positive bacterial strains. CONCLUSIONS: We found new noncovalent inhibitors of PBPs which represent important starting points for development of more potent inhibitors of PBPs that can target penicillin-resistant bacteria.

  7. Mutation in ribosomal protein S5 leads to spectinomycin resistance in Neisseria gonorrhoeae.

    Science.gov (United States)

    Ilina, Elena N; Malakhova, Maya V; Bodoev, Ivan N; Oparina, Nina Y; Filimonova, Alla V; Govorun, Vadim M

    2013-01-01

    Spectinomycin remains a useful reserve option for therapy of gonorrhea. The emergence of multidrug-resistant Neisseria gonorrhoeae strains with decreased susceptibility to cefixime and to ceftriaxone makes it the only medicine still effective for treatment of gonorrhea infection in analogous cases. However, adoption of spectinomycin as a routinely used drug of choice was soon followed by reports of spectinomycin resistance. The main molecular mechanism of spectinomycin resistance in N. gonorrhoeae was C1192T substitution in 16S rRNA genes. Here we reported a Thr-24→Pro mutation in ribosomal protein S5 (RPS5) found in spectinomycin resistant clinical N. gonorrhoeae strain, which carried no changes in 16S rRNA. In a series of experiments, the transfer of rpsE gene allele encoding the mutant RPS5 to the recipient N. gonorrhoeae strains was analyzed. The relatively high rate of transformation [ca. 10(-5) colony-forming units (CFUs)] indicates the possibility of spread of spectinonycin resistance within gonococcal population due to the horizontal gene transfer (HGT).

  8. An evolutionary comparative scan for longevity-related oxidative stress resistance mechanisms in homeotherms.

    Science.gov (United States)

    Pamplona, Reinald; Barja, Gustavo

    2011-10-01

    Key mechanisms relating oxidative stress to longevity from an interespecies comparative approach are reviewed. Long-lived animal species show low rates of reactive oxygen species (ROS) generation and oxidative damage at their mitochondria. Comparative physiology also shows that the specific compositional pattern of tissue macromolecules (proteins, lipids and nucleic acids) in long-lived animal species gives them an intrinsically high resistance to modification that likely contributes to their superior longevity. This is obtained in the case of lipids by decreasing the degree of fatty acid unsaturation, and in the case of proteins by lowering their methionine content. These findings are also substantiated from a phylogenomic approach. Nutritional or/and pharmacological interventions focused to modify some of these molecular traits were translated with modifications in animal longevity. It is proposed that natural selection tends to decrease the mitochondrial ROS generation and to increase the molecular resistance to the oxidative damage in long-lived species.

  9. 胃癌细胞多药耐药相关蛋白质筛选鉴定的蛋白质组学研究%Identification of multidrug resistance related proteins in different gastric carcinoma cell lines by comparative proteomics

    Institute of Scientific and Technical Information of China (English)

    李勇; 檀碧波; 范立侨; 赵群; 刘羽; 赵雪峰

    2011-01-01

    Objective To investigate multidrug resistance related proteins in human gastric carci noma cell lines SGC7901 and SGC7901/VCR by comparative proteomics.Methods After culture,the holoproteins of human gastric carcinoma cell lines SGC7901 and GC7901/VCR were extracted,and then measured by two-dimensional gel electrophoresis and matrix assisted laser desorption/ionization time-offlight mass spectrometry (MALDI-TOF-MS).Some proteins obtained through proteomics were tested by Western blotting in the cell lines.Results There were different proteins in these 2 human gastric carcinoma cell lines.Nine different protein spots were found in these 2 gastric carcinoma cell lines,and 7 spots were identified by MALDI-TOF-MS,and these proteins were 60S ribosomal protein L23 ( RL23),voltagedependent anion-selective channel protein-1 (VDAC1),zinc finger protein (ZNF) 394,keratin,type Ⅰcytoskeletal 9 ( KIC9),RNA 3' -terminal phosphate cyclase 1 ( RTC1 ),zinc finger matrin-type protein 2,Sideroflexin-1.These proteins had a direct relationship with multidrug resistance in gastric carcinoma.Results of Western blotting about protein expression were in consonance with those of proteomics.Conclusion Different proteins were found in human gastric carcinoma cell lines SGC7901 and SGC7901/VCR.%目的 在胃癌细胞株SGC7901及稳定的耐药细胞株SGC7901/VCR中寻找与胃癌多药耐药(MDR)直接相关的蛋白质,观察其功能.方法 胃癌细胞株SGC7901和稳定的耐药细胞株SGC7901/VCR培养后提取总蛋白,采用蛋白质组学技术(双向凝胶电泳和基质辅助激光解吸电离-飞行时间质谱鉴定)筛选并鉴定差异表达的蛋白质,并应用蛋白印迹试验法对鉴定出的部分蛋白质在胃癌细胞株中的表达进行验证.结果 在两种细胞株中找到表达差异明显的蛋白质点9个,经质谱分析,7种蛋白质得到鉴定,为S60核糖体蛋白L23、电压依赖性阴离子选择性通道蛋白1、锌指蛋白394

  10. Protein interaction network related to Helicobacter pylori infection response

    Institute of Scientific and Technical Information of China (English)

    Kyu Kwang Kim; Han Bok Kim

    2009-01-01

    AIM: To understand the complex reaction of gastric inflammation induced by Helicobacter pylori (H pylori ) in a systematic manner using a protein interaction network. METHODS: The expression of genes significantly changed on microarray during H pylori infection was scanned from the web literary database and translated into proteins. A network of protein interactions was constructed by searching the primary interactions of selected proteins. The constructed network was mathematically analyzed and its biological function was examined. In addition, the nodes on the network were checked to determine if they had any further functional importance or relation to other proteins by extending them.RESULTS: The scale-free network showing the relationship between inflammation and carcinogenesis was constructed. Mathematical analysis showed hub and bottleneck proteins, and these proteins were mostly related to immune response. The network contained pathways and proteins related to H pylori infection, such as the JAK-STAT pathway triggered by interleukins. Activation of nuclear factor (NF)-kB, TLR4, and other proteins known to function as core proteins of immune response were also found.These immune-related proteins interacted on the network with pathways and proteins related to the cell cycle, cell maintenance and proliferation, and transcription regulators such as BRCA1, FOS, REL, and zinc finger proteins. The extension of nodes showed interactions of the immune proteins with cancerrelated proteins. One extended network, the core network, a summarized form of the extended network, and cell pathway model were constructed. CONCLUSION: Immune-related proteins activated by H pylori infection interact with proto-oncogene proteins. The hub and bottleneck proteins are potential drug targets for gastric inflammation and cancer.

  11. Protein Interactions between Fe65, the LDL receptor-related protein and the amyloid precursor protein

    Science.gov (United States)

    Mulvihill, Melinda; Guttman, Miklos; Komives, Elizabeth A.

    2011-01-01

    The adapter protein, Fe65 has been proposed to be the link between the intracellular domains of the amyloid precursor protein, APP (AICD) and the LDL receptor-related protein (LRP-CT). Functional linkage between these two proteins has been established and mutations within LRP-CT affect the amount of Aβ produced from APP. Previous work showed that the AICD binds to the protein interaction domain 2 (PID2) of Fe65. Although the structure of PID1 was solved recently all attempts to demonstrate LRP-CT binding to this domain failed. We used biophysical experiments and binding studies to investigate the binding between these three proteins. Full-length Fe65 bound more weakly to AICD than did N-terminally truncated forms, however the intramolecular domain-domain interactions that had been proposed to inhibit binding could not be observed using amide H/D exchange. Surprisingly, when the LRP-CT is phosphorylated at Tyr4507, it bound to Fe65-PID1 despite the fact that this domain belongs to the Dab-like subclass of PIDs that is not supposed to be phosphorylation dependent. Mutation of a critical arginine abolished binding providing further proof of the phosphorylation-dependence. The Fe65-PID1 domain thus provides a link between the Dab-like class and the IRS-like class of PID domains and is the first Dab-like family member to show phosphorylation-dependent binding. PMID:21650223

  12. Proteins Related to the Biocontrol of Pythium Damping-off in Maize with Trichoderma harzianum Rifai

    Institute of Scientific and Technical Information of China (English)

    Jie CHEN; Gary E HARMAN; Afio COMIS; Gen-Wu CHENG

    2005-01-01

    Induced resistance has been evidenced as one of mechanisms of Trichoderma to control plantdiseases, however, no study showed the change of host proteomics in Trichoderma-induced resistance ofmaize against damping-off caused by Pythium ultimum Trow. The mechanism of Trichoderma harzianumRifai for controlling maize seedling disease caused by Pythium ultimum Trow was investigated firstly byproteome technique and the result suggested that T. harzianum strain T22 was not only able to promoteseedling growth but also protein accumulation. One-dimensional electrophoresis assay showed that morebands appeared on the gel with T22 or T22 combined with P. ultimum (T22 + P. ultimum) treatment than withother treatments. Enzyme assay showed that two chitinases of the root sample were more activated in thetreatments with T22 than in the other treatments without T22. Proteins in the seedling roots from the varioustreatments were separated through protein extraction and 2-D electrophoresis technique. In the seedlingsproduced from the T22-treated seeds, there were 104 up-regulated proteins and 164 down-regulated pro-teins relative to the control, and 97 and 150, respectively, after treatment with T22 + P. ultimum; however,with P. ultimum alone the values were much lower than with the other two treatments. The correlationcoefficient values were 0.72, 0.51 and 0.49 for the comparison of protein spot distribution on gel amongcontrol with T22, P. ultimum and T22 + P. ultimum, respectively. So it seemed that P. ultimum infection wasmore effective than T22 in interfering with the host proteome profile. Furthermore, analysis with MALDI-TOF-MAS showed that some important proteins associated with defensive reactions were identified in T22or T22 + P. ultimum treatments, including endochitinase, pathogenesis-related protein PRMS (pathogenesis-related maize seed), GTP-binding protein, isoflavone reductase and other proteins related to respiration. Allthose proteins are probably part of the

  13. EXPRESSION AND REVERSION OF DRUG RESISTANCE-AND APOPTOSIS-RELATED GENES OF A DDP-RESISTANT LUNG ADENOCARCINOMA CELL LINE

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To investigate the co-expression of drug resistance- and apoptosis-related genes of cisplatin (CDDP)-selected lung adenocarcinoma cell line A549DDP for compared to the parental cell line A549, and reverse of drug resistance by antisense s-oligodeoxynucleotides (S-ODNs) of differentially expressed genes. Methods: Sense and antisense S-ODN were transferred into A549DDP cells by lipofectin. The expression of drug resistance and apoptosis related genes was examined by RT-PCR, immunocytochemistry and flow cytometry, respectively. Apoptostic cells were identified by DNA electrophoresis and terminal deoxynucleotidyl transferase (TdT)-mediated biotin dUTP nick end-labeling(TUNEL). Drug resistance of tumor cells was detected by a cell viability (MTT) assay. Results: The expression of bc1-2 was positive and that of multidrug resistance-associated protein (MRP) at mRNA and protein level was increased in A549DDP compared to A549 cells. MDR1, c-myc and topoisomeras II (TOPO II) were similarly co-expressed in two cell lines. Both cell lines were negative for c-erbB-2 expression. In A549DDP cells, the expression of bc1-2 and MRP was significantly inhibited by their respective antisense S-ODNs. Antisense S-ODNs could also decrease significantly drug resistance of A549DDP cells to CDDP by promoting cell apoptosis. Conclusion: Both intrinsic and acquired drug resistance were involved in co-expression of multiple MDR-related genes in lung adenocarcinoma. Co- operation of bc1-2 and MRP genes appeared to play an important action to confer the resistance of A549DDP cells to CDDP. Their antisense S-ODNs are responsible for the decrease of drug resistance of this cell line by promoting apoptosis.

  14. A novel inducible protein production system and neomycin resistance as selection marker for Methanosarcina mazei.

    Science.gov (United States)

    Mondorf, Sebastian; Deppenmeier, Uwe; Welte, Cornelia

    2012-01-01

    Methanosarcina mazei is one of the model organisms for the methanogenic order Methanosarcinales whose metabolism has been studied in detail. However, the genetic toolbox is still limited. This study was aimed at widening the scope of utilizable methods in this group of organisms. (i) Proteins specific to methanogens are oftentimes difficult to produce in E. coli. However, a protein production system is not available for methanogens. Here we present an inducible system to produce Strep-tagged proteins in Ms. mazei. The promoter p1687, which directs the transcription of methyl transferases that demethylate methylamines, was cloned into plasmid pWM321 and its activity was determined by monitoring β-glucuronidase production. The promoter was inactive during growth on methanol but was rapidly activated when trimethylamine was added to the medium. The gene encoding the β-glucuronidase from E. coli was fused to a Strep-tag and was cloned downstream of the p1687 promoter. The protein was overproduced in Ms. mazei and was purified in an active form by affinity chromatography. (ii) Puromycin is currently the only antibiotic used as a selectable marker in Ms. mazei and its relatives. We established neomycin resistance as a second selectable marker by designing a plasmid that confers neomycin resistance in Ms. mazei.

  15. A Novel Inducible Protein Production System and Neomycin Resistance as Selection Marker for Methanosarcina mazei

    Directory of Open Access Journals (Sweden)

    Sebastian Mondorf

    2012-01-01

    Full Text Available Methanosarcina mazei is one of the model organisms for the methanogenic order Methanosarcinales whose metabolism has been studied in detail. However, the genetic toolbox is still limited. This study was aimed at widening the scope of utilizable methods in this group of organisms. (i Proteins specific to methanogens are oftentimes difficult to produce in E. coli. However, a protein production system is not available for methanogens. Here we present an inducible system to produce Strep-tagged proteins in Ms. mazei. The promoter p1687, which directs the transcription of methyl transferases that demethylate methylamines, was cloned into plasmid pWM321 and its activity was determined by monitoring β-glucuronidase production. The promoter was inactive during growth on methanol but was rapidly activated when trimethylamine was added to the medium. The gene encoding the β-glucuronidase from E. coli was fused to a Strep-tag and was cloned downstream of the p1687 promoter. The protein was overproduced in Ms. mazei and was purified in an active form by affinity chromatography. (ii Puromycin is currently the only antibiotic used as a selectable marker in Ms. mazei and its relatives. We established neomycin resistance as a second selectable marker by designing a plasmid that confers neomycin resistance in Ms. mazei.

  16. Effects of soy protein and isoflavones on insulin resistance and adiponectin in male monkeys.

    Science.gov (United States)

    Wagner, Janice D; Zhang, Li; Shadoan, Melanie K; Kavanagh, Kylie; Chen, Haiying; Tresnasari, Kristianti; Kaplan, Jay R; Adams, Michael R

    2008-07-01

    Isoflavones may influence insulin action by means of their well-known receptor-mediated estrogenic activity. However, isoflavones also bind to peroxisome proliferator-activated receptors (PPARs) that are strongly associated with insulin action. Soy protein with its isoflavones has previously been shown to improve glycemic control in diabetic postmenopausal women and to improve insulin sensitivity in ovariectomized monkeys. The purpose of the current report was to extend our studies of dietary soy protein to male monkeys and determine effects of the soy isoflavones on insulin resistance. Two studies are reported here. Study one involved 91 male monkeys consuming 3 diets differing only by the source of protein (casein-lactalbumin, soy protein with a low isoflavone concentration, or soy protein with a high isoflavone concentration). Intravenous glucose tolerance tests were done, and plasma adiponectin and lipoprotein concentrations were determined after 25 months of study. Samples of visceral fat were obtained at 31 months for assessment of adiponectin and PPARgamma expression. The second study involved 8 monkeys in a Latin-square design that compared the effects of diets with casein/lactalbumin, soy protein with a high isoflavone concentration, or soy protein that was alcohol-washed to deplete the isoflavones. After 8 weeks of treatment, insulin sensitivity and plasma lipoproteins were assessed. At 10 weeks, a biopsy of the skeletal muscle was performed for determination of insulin receptor, PPARalpha, and PPARgamma content. The major findings were that consumption of isoflavone-containing soy protein dose-dependently increased insulin responses to the glucose challenge and decreased plasma adiponectin, whereas isoflavone-depleted soy protein decreased body weight and had no effect on plasma adiponectin concentrations. Muscle PPARalpha and gamma expression was also increased with the isoflavone-depleted soy relative to either casein or soy protein containing the

  17. The clinical expression of hereditary protein C and protein S deficiency: : a relation to clinical thrombotic risk-factors and to levels of protein C and protein S

    NARCIS (Netherlands)

    Henkens, C. M. A.; van der Meer, J.; Hillege, J. L.; Bom, V. J. J.; Halie, M. R.; van der Schaaf, W.

    We investigated 103 first-degree relatives of 13 unrelated protein C or protein S deficient patients to assess the role of additional thrombotic risk factors and of protein C and protein S levels in the clinical expression of hereditary protein C and protein S deficiency. Fifty-seven relatives were

  18. Structure-function analysis of the NB-ARC domain of plant disease resistance proteins

    NARCIS (Netherlands)

    van Ooijen, G.; Mayr, G.; Kasiem, M.M.A.; Albrecht, M.; Cornelissen, B.J.C.; Takken, F.L.W.

    2008-01-01

    Resistance (R) proteins in plants are involved in pathogen recognition and subsequent activation of innate immune responses. Most resistance proteins contain a central nucleotide-binding domain. This so-called NB-ARC domain consists of three subdomains: NB, ARC1, and ARC2. The NB-ARC domain is a fun

  19. Role of multidrug resistance protein (MRP) in glutathione S-conjugate transport in mammalian cells

    NARCIS (Netherlands)

    Muller, M; deVries, EGE; Jansen, PLM

    1996-01-01

    The human multidrug resistance protein (MRP), a 190-kDa member of the ABC-protein superfamily, is an ATP-dependent glutathione S-conjugate carrier (GS-X pump) and is present in membranes of many, if not all, cells, Overexpression of MRP in tumor cells contributes to resistance to natural product dru

  20. Protein defence systems against the lantibiotic nisin: Function of the immunity protein NisI and the resistance protein NSR

    Directory of Open Access Journals (Sweden)

    Sakshi eKhosa

    2016-04-01

    Full Text Available Lantibiotics are potential alternatives to antibiotics because of their broad-range killing spectrum. The producer strain is immune against its own synthesized lantibiotic via the expression of two proteins LanI and LanFEG. Recently, gene operons are found in mainly human pathogenic strains, which confer resistance against lantibiotics. Of all the lantibiotics discovered till date, nisin produced by some L. lactis strains is the most prominent member. Nisin has multiple mode of actions of which binding to the cell wall precursor lipid II and subsequent insertion into the bacterial membrane to form pores are the most effective. The nisin producing strains express the lipoprotein NisI to prevent a suicidal effect. NisI binds nisin, inducing a reversible cell clustering to prevent nisin from reaching the membrane. Importantly NisI does not modify nisin and releases it as soon as the concentration in the media drops below a certain level. The human pathogen S. agalactiae is naturally resistant against nisin by expressing a resistance protein called SaNSR, which is a nisin degrading enzyme. By cleaving off the last six amino acids of nisin, its effectiveness is 100-fold reduced. This cleavage reaction appears to be specific for nisin since SaNSR recognizes the C-terminal located lanthionine rings. Recently, the structures of both NisI and SaNSR were determined by NMR and X-ray crystallography, respectively. Furthermore, for both proteins the binding site for nisin was determined. Within this review, the structures of both proteins and their different defence mechanisms are described.

  1. Protein Defense Systems against the Lantibiotic Nisin: Function of the Immunity Protein NisI and the Resistance Protein NSR

    Science.gov (United States)

    Khosa, Sakshi; Lagedroste, Marcel; Smits, Sander H. J.

    2016-01-01

    Lantibiotics are potential alternatives to antibiotics because of their broad-range killing spectrum. The producer strain is immune against its own synthesized lantibiotic via the expression of two proteins LanI and LanFEG. Recently, gene operons are found in mainly human pathogenic strains, which confer resistance against lantibiotics. Of all the lantibiotics discovered till date, nisin produced by some Lactococcus lactis strains is the most prominent member. Nisin has multiple mode of actions of which binding to the cell wall precursor lipid II and subsequent insertion into the bacterial membrane to form pores are the most effective. The nisin producing strains express the lipoprotein NisI to prevent a suicidal effect. NisI binds nisin, inducing a reversible cell clustering to prevent nisin from reaching the membrane. Importantly NisI does not modify nisin and releases it as soon as the concentration in the media drops below a certain level. The human pathogen Streptococcus agalactiae is naturally resistant against nisin by expressing a resistance protein called SaNSR, which is a nisin degrading enzyme. By cleaving off the last six amino acids of nisin, its effectiveness is 100-fold reduced. This cleavage reaction appears to be specific for nisin since SaNSR recognizes the C-terminal located lanthionine rings. Recently, the structures of both NisI and SaNSR were determined by NMR and X-ray crystallography, respectively. Furthermore, for both proteins the binding site for nisin was determined. Within this review, the structures of both proteins and their different defense mechanisms are described. PMID:27148193

  2. Deficiency of a Glycogen Synthase-associated Protein, Epm2aip1, Causes Decreased Glycogen Synthesis and Hepatic Insulin Resistance*

    Science.gov (United States)

    Turnbull, Julie; Tiberia, Erica; Pereira, Sandra; Zhao, Xiaochu; Pencea, Nela; Wheeler, Anne L.; Yu, Wen Qin; Ivovic, Alexander; Naranian, Taline; Israelian, Nyrie; Draginov, Arman; Piliguian, Mark; Frankland, Paul W.; Wang, Peixiang; Ackerley, Cameron A.; Giacca, Adria; Minassian, Berge A.

    2013-01-01

    Glycogen synthesis is a major component of the insulin response, and defective glycogen synthesis is a major portion of insulin resistance. Insulin regulates glycogen synthase (GS) through incompletely defined pathways that activate the enzyme through dephosphorylation and, more potently, allosteric activation. We identify Epm2aip1 as a GS-associated protein. We show that the absence of Epm2aip1 in mice impairs allosteric activation of GS by glucose 6-phosphate, decreases hepatic glycogen synthesis, increases liver fat, causes hepatic insulin resistance, and protects against age-related obesity. Our work identifies a novel GS-associated GS activity-modulating component of insulin resistance. PMID:24142699

  3. Rare disease relations through common genes and protein interactions.

    Science.gov (United States)

    Fernandez-Novo, Sara; Pazos, Florencio; Chagoyen, Monica

    2016-06-01

    ODCs (Orphan Disease Connections), available at http://csbg.cnb.csic.es/odcs, is a novel resource to explore potential molecular relations between rare diseases. These molecular relations have been established through the integration of disease susceptibility genes and human protein-protein interactions. The database currently contains 54,941 relations between 3032 diseases.

  4. Plasma phospholipid transfer protein activity is independently determined by obesity and insulin resistance in non-diabetic subjects

    NARCIS (Netherlands)

    de Vries, Rindert; Kappelle, Paul J.W.H.; Dallinga-Thie, Geesje M.; Dullaart, Robin P. F.

    2011-01-01

    Background: Phospholipid transfer protein (PLTP) is an emerging cardio-metabolic risk factor which is intricately involved in lipoprotein metabolism. Elevated plasma PLTP activity levels are reported in obesity and diabetes mellitus, but the relative contributions of obesity and insulin resistance t

  5. Plasma phospholipid transfer protein activity is independently determined by obesity and insulin resistance in non-diabetic subjects

    NARCIS (Netherlands)

    de Vries, Rindert; Kappelle, Paul J.W.H.; Dallinga-Thie, Geesje M.; Dullaart, Robin P. F.

    2011-01-01

    Background: Phospholipid transfer protein (PLTP) is an emerging cardio-metabolic risk factor which is intricately involved in lipoprotein metabolism. Elevated plasma PLTP activity levels are reported in obesity and diabetes mellitus, but the relative contributions of obesity and insulin resistance t

  6. Plasma phospholipid transfer protein activity is independently determined by obesity and insulin resistance in non-diabetic subjects

    NARCIS (Netherlands)

    de Vries, Rindert; Kappelle, Paul J.W.H.; Dallinga-Thie, Geesje M.; Dullaart, Robin P. F.

    Background: Phospholipid transfer protein (PLTP) is an emerging cardio-metabolic risk factor which is intricately involved in lipoprotein metabolism. Elevated plasma PLTP activity levels are reported in obesity and diabetes mellitus, but the relative contributions of obesity and insulin resistance

  7. Effect of protein/essential amino acids and resistance training on skeletal muscle hypertrophy: A case for whey protein

    Directory of Open Access Journals (Sweden)

    Stout Jeffrey R

    2010-06-01

    Full Text Available Abstract Regardless of age or gender, resistance training or provision of adequate amounts of dietary protein (PRO or essential amino acids (EAA can increase muscle protein synthesis (MPS in healthy adults. Combined PRO or EAA ingestion proximal to resistance training, however, can augment the post-exercise MPS response and has been shown to elicit a greater anabolic effect than exercise plus carbohydrate. Unfortunately, chronic/adaptive response data comparing the effects of different protein sources is limited. A growing body of evidence does, however, suggest that dairy PRO, and whey in particular may: 1 stimulate the greatest rise in MPS, 2 result in greater muscle cross-sectional area when combined with chronic resistance training, and 3 at least in younger individuals, enhance exercise recovery. Therefore, this review will focus on whey protein supplementation and its effects on skeletal muscle mass when combined with heavy resistance training.

  8. Bioinformatics analysis of metastasis-related proteins in hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Pei-Ming Song; Yang Zhang; Yu-Fei He; Hui-Min Bao; Jian-Hua Luo; Yin-Kun Liu; Peng-Yuan Yang; Xian Chen

    2008-01-01

    AIM: To analyze the metastasis-related proteins in hepatocellular carcinoma (HCC) and discover the biomark-er candidates for diagnosis and therapeutic intervention of HCC metastasis with bioinformatics tools.METHODS: Metastasis-related proteins were determined by stable isotope labeling and MS analysis and analyzed with bioinformatics resources, including Phobius, Kyoto encyclopedia of genes and genomes (KEGG), online mendelian inheritance in man (OHIH) and human protein reference database (HPRD).RESULTS: All the metastasis-related proteins were linked to 83 pathways in KEGG, including MAPK and p53 signal pathways. Protein-protein interaction network showed that all the metastasis-related proteins were categorized into 19 function groups, including cell cycle, apoptosis and signal transcluction. OMIM analysis linked these proteins to 186 OMIM entries.CONCLUSION: Metastasis-related proteins provide HCC cells with biological advantages in cell proliferation, migration and angiogenesis, and facilitate metastasis of HCC cells. The bird's eye view can reveal a global charac-teristic of metastasis-related proteins and many differen-tially expressed proteins can be identified as candidates for diagnosis and treatment of HCC.

  9. Breast cancer resistance protein (BCRP) in acute leukemia

    NARCIS (Netherlands)

    Plasschaert, SLA; van der Kolk, Dorina M.; De Bont, ESJM; Vellenga, E; Kamps, WA; De Vries, EGE

    Multidrug resistance, cross- resistance to structurally and functionally unrelated drugs, is an important cause of treatment failure in acute leukemia. Multidrug resistance can result from the overexpression of ATP- dependent efflux pumps, such as P- glycoprotein and members of the multidrug

  10. C-reactive protein, insulin resistance and risk of cardiovascular disease: a population-based study

    DEFF Research Database (Denmark)

    Hansen, T.W.; Olsen, M.H.; Rasmussen, S.

    2008-01-01

    ischaemic heart disease and nonfatal stroke, amounted to 222 cases. In Cox proportional-hazard models, adjusted for age, sex, smoking habit, total cholesterol, waist circumference, levels of triglycerides and high-density lipoprotein-cholesterol, systolic and diastolic blood pressures, physical activity......BACKGROUND: C-reactive protein (CRP), a marker of inflammation, and insulin resistance (IR), a metabolic disorder, are closely related. CRP and IR have both been identified as significant risk factors of cardiovascular disease (CVD) after adjustment for conventional CVD risk factors...

  11. Light-load resistance exercise increases muscle protein synthesis and hypertrophy signaling in elderly men

    DEFF Research Database (Denmark)

    Agergaard, Jakob; Bülow, Jacob; Jensen, Jacob K

    2017-01-01

    INTRODUCTION: The present study investigated whether well-tolerated light-load resistance exercise (LL-RE) affects skeletal muscle fractional synthetic rate (FSR) and anabolic intracellular signaling as a way to counteract age-related loss of muscle mass. METHODS: Untrained healthy men (age: +65...... and 12g whey protein at 7 hours post-exercise; N=10) or placebo (4g maltodextrin/hour; N=10). Quadriceps muscle biopsies were taken at 0, 3, 7 and 10 hours post-exercise from both the resting and exercised leg. Myofibrillar-FSR and activity of select targets from the mTORC1-signalling cascade were...

  12. Mutations outside the YMDD motif in the P protein can also cause DHBV resistant to Lamivudine

    Institute of Scientific and Technical Information of China (English)

    Jin-Yang He; Yu-Tong Zhu; Rui-Yi Yang; Li-Ling Feng; Xing-Bo Guo; Feng-Xue Zhang; Hong-Shan Chen

    2005-01-01

    AIM: To observe the Lamivudine resistance character of a DHBV strain in vitro and in vivo, and to analyze if the Lamivudine resistance character is caused by gene mutation or by abnormity of the Lamivudine metabolism.METHODS: Congenitally DHBV-negative Guangdong brown ducks and duck embryo liver cells were respectively taken as animal and cell model. The Lamivudine-susceptive DHBV and Lamivudine-resistant DHBV (LRDHBV) were infected and Lamivudine was administrated according to the divided groups. The changes of DHBV quantity in the animal and cell model were tested. Three Lamivudineresistant and two Lamivudine-susceptive DHBV complete genomes were successfully amplified, sequenced and then submitted to GenBank. All the DHBV complete sequences in the GenBank at present were taken to align with the three LRDHBV to analyze the mutational points related to the Lamivudine-resistant mutation.RESULTS: Both the animal and cell model showed that the large and the small dosage Lamivudine have no significant inhibitory effect on the LRDHBV. Five sequences of DHBV complete genomes were successfully cloned. The GenBank accession numbers of the three sequences of LRDHBV are AY521226, AY521227, and AY433937. The two strains of Lamivudine-susceptive DHBV are AY392760and AY536371. The correlated mutational points are KorR86Q and AorE591T in the P protein.CONCLUSION: The Lamivudine resistance character of this DHBV strain is caused by genome mutation; the related mutational points are KorR86Q and AorE591T and have no relations with the YMDD motif mutation.

  13. Comparative proteomic analysis of horseweed (Conyza canadensis) biotypes identifies candidate proteins for glyphosate resistance.

    Science.gov (United States)

    González-Torralva, Fidel; Brown, Adrian P; Chivasa, Stephen

    2017-02-15

    Emergence of glyphosate-resistant horseweed (Conyza canadensis) biotypes is an example of how unrelenting use of a single mode of action herbicide in agricultural weed control drives genetic adaptation in targeted species. While in other weeds glyphosate resistance arose from target site mutation or target gene amplification, the resistance mechanism in horseweed uses neither of these, being instead linked to reduced herbicide uptake and/or translocation. The molecular components underpinning horseweed glyphosate-resistance remain unknown. Here, we used an in vitro leaf disc system for comparative analysis of proteins extracted from control and glyphosate-treated tissues of glyphosate-resistant and glyphosate-susceptible biotypes. Analysis of shikimic acid accumulation, ABC-transporter gene expression, and cell death were used to select a suitable glyphosate concentration and sampling time for enriching proteins pivotal to glyphosate resistance. Protein gel analysis and mass spectrometry identified mainly chloroplast proteins differentially expressed between the biotypes before and after glyphosate treatment. Chloroplasts are the organelles in which the shikimate pathway, which is targeted by glyphosate, is located. Calvin cycle enzymes and proteins of unknown function were among the proteins identified. Our study provides candidate proteins that could be pivotal in engendering resistance and implicates chloroplasts as the primary sites driving glyphosate-resistance in horseweed.

  14. Comparative proteomic analysis of horseweed (Conyza canadensis) biotypes identifies candidate proteins for glyphosate resistance

    Science.gov (United States)

    González-Torralva, Fidel; Brown, Adrian P.; Chivasa, Stephen

    2017-01-01

    Emergence of glyphosate-resistant horseweed (Conyza canadensis) biotypes is an example of how unrelenting use of a single mode of action herbicide in agricultural weed control drives genetic adaptation in targeted species. While in other weeds glyphosate resistance arose from target site mutation or target gene amplification, the resistance mechanism in horseweed uses neither of these, being instead linked to reduced herbicide uptake and/or translocation. The molecular components underpinning horseweed glyphosate-resistance remain unknown. Here, we used an in vitro leaf disc system for comparative analysis of proteins extracted from control and glyphosate-treated tissues of glyphosate-resistant and glyphosate-susceptible biotypes. Analysis of shikimic acid accumulation, ABC-transporter gene expression, and cell death were used to select a suitable glyphosate concentration and sampling time for enriching proteins pivotal to glyphosate resistance. Protein gel analysis and mass spectrometry identified mainly chloroplast proteins differentially expressed between the biotypes before and after glyphosate treatment. Chloroplasts are the organelles in which the shikimate pathway, which is targeted by glyphosate, is located. Calvin cycle enzymes and proteins of unknown function were among the proteins identified. Our study provides candidate proteins that could be pivotal in engendering resistance and implicates chloroplasts as the primary sites driving glyphosate-resistance in horseweed. PMID:28198407

  15. The effects of whey protein with or without carbohydrates on resistance training adaptations.

    Science.gov (United States)

    Hulmi, Juha J; Laakso, Mia; Mero, Antti A; Häkkinen, Keijo; Ahtiainen, Juha P; Peltonen, Heikki

    2015-01-01

    Nutrition intake in the context of a resistance training (RT) bout may affect body composition and muscle strength. However, the individual and combined effects of whey protein and carbohydrates on long-term resistance training adaptations are poorly understood. A four-week preparatory RT period was conducted in previously untrained males to standardize the training background of the subjects. Thereafter, the subjects were randomized into three groups: 30 g of whey proteins (n = 22), isocaloric carbohydrates (maltodextrin, n = 21), or protein + carbohydrates (n = 25). Within these groups, the subjects were further randomized into two whole-body 12-week RT regimens aiming either for muscle hypertrophy and maximal strength or muscle strength, hypertrophy and power. The post-exercise drink was always ingested immediately after the exercise bout, 2-3 times per week depending on the training period. Body composition (by DXA), quadriceps femoris muscle cross-sectional area (by panoramic ultrasound), maximal strength (by dynamic and isometric leg press) and serum lipids as basic markers of cardiovascular health, were analysed before and after the intervention. Twelve-week RT led to increased fat-free mass, muscle size and strength independent of post-exercise nutrient intake (P carbohydrate group independent of the type of RT (P carbohydrate group (P carbohydrates or combination of proteins and carbohydrates did not have a major effect on muscle size or strength when ingested two to three times a week. However, whey proteins may increase abdominal fat loss and relative fat-free mass adaptations in response to resistance training when compared to fast-acting carbohydrates.

  16. Arabidopsis Heterotrimeric G-protein Regulates Cell Wall Defense and Resistance to Necrotrophic Fungi

    Institute of Scientific and Technical Information of China (English)

    Magdalena Delcado-Cerezo; Paul Schulze-Lefert; Shauna Somerville; José Manuel Estevez; Staffan Persson; Antonio Molina; Clara Sánchez-Rodríguez; Viviana Escudero; Eva Miedes; Paula Virginia Fernández; Lucía Jordá; Camilo Hernández-Blanco; Andrea Sánchez-Vallet; Pawel Bednarek

    2012-01-01

    The Arabidopsis heterotrimeric G-protein controls defense responses to necrotrophic and vascular fungi.The agb1 mutant impaired in the Gβ subunit displays enhanced susceptibility to these pathogens.Gβ/AGB1 forms an obligate dimer with either one of the Arabidopsis Gγ subunits (γ1/AGG1 and γ2/AGG2).Accordingly,we now demonstrate that the agg1 agg2 double mutant is as susceptible as agb1 plants to the necrotrophic fungus Plectosphaerella cucumerina.To elucidate the molecular basis of heterotrimeric G-protein-mediated resistance,we performed a comparative transcriptomic analysis of agb1-1 mutant and wild-type plants upon inoculation with P cucumerina.This analysis,together with metabolomic studies,demonstrated that G-protein-mediated resistance was independent of defensive pathways required for resistance to necrotrophic fungi,such as the salicylic acid,jasmonic acid,ethylene,abscisic acid,and tryptophan-derived metabolites signaling,as these pathways were not impaired in agb1 and agg1 agg2 mutants.Notably,many mis-regulated genes in agb1 plants were related with cell wall functions,which was also the case in agg1 agg2 mutant.Biochemical analyses and Fourier Transform InfraRed (FTIR) spectroscopy of cell walls from G-protein mutants revealed that the xylose content was lower in agb1 and agg1 agg2 mutants than in wild-type plants,and that mutant walls had similar FTIR spectratypes,which differed from that of wild-type plants.The data presented here suggest a canonical functionality of the Gβ and Gγ1/γ2 subunits in the control of Arabidopsis immune responses and the regulation of cell wall composition.

  17. Glyphosate-Resistant Parthenium hysterophorus in the Caribbean Islands: Non Target Site Resistance and Target Site Resistance in Relation to Resistance Levels.

    Directory of Open Access Journals (Sweden)

    Enzo Bracamonte

    2016-12-01

    Full Text Available Glyphosate has been the most intensely herbicide used worldwide for decades, and continues to be a single tool for controlling weeds in woody crops. However, the adoption of this herbicide in a wide range of culture systems has led to the emergence of resistant weeds. Glyphosate has been widely used primarily on citrus in the Caribbean area, but a study of resistance in the Caribbean islands of Cuba and the Dominican Republic has never been carried out. Unfortunately, Parthenium hysterophorus has developed glyphosate-resistance in both islands, independently. The resistance level and mechanisms of different P. hysterophorus accessions (three collected in Cuba (Cu-R and four collected in the Dominican Republic (Do-R have been studied under greenhouse and laboratory conditions. In in vivo assays (glyphosate dose causing 50% reduction in above-ground vegetative biomass and survival, the resistance factor levels showed susceptible accessions (Cu-S≥Do-S, low-resistance accessions (Cu-R3Do-R2>Cu-R2>Do-R3>Do-R4>Cu-R3>>Cu-S≥Do-S. Glyphosate was degraded to aminomethylphosphonic acid, glyoxylate and sarcosine by >88% in resistant accessions except in Cu-R3 and Do-R4 resistant accessions (51.12 and 44.21, respectively, whereas a little glyphosate (<9.32% was degraded in both susceptible accessions at 96 h after treatment. There were significant differences between P. hysterophorus accessions in the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS activity enzyme with and without different glyphosate rates. The R accessions showed values of between 0.026 and 0.21 µmol µg-1 TSP protein min-1 basal EPSPS activity values with respect to the S (0.024 and 0.025 accessions. The same trend was found in the EPSPS enzyme activity treated with glyphosate, where a higher enzyme activity inhibition (glyphosate µM corresponded to greater resistance levels in P. hysterophorus accessions. One amino acid substitution was found at position 106 in EPSPS, consisting

  18. Glyphosate-Resistant Parthenium hysterophorus in the Caribbean Islands: Non Target Site Resistance and Target Site Resistance in Relation to Resistance Levels.

    Science.gov (United States)

    Bracamonte, Enzo; Fernández-Moreno, Pablo T; Barro, Francisco; De Prado, Rafael

    2016-01-01

    Glyphosate has been the most intensely herbicide used worldwide for decades, and continues to be a single tool for controlling weeds in woody crops. However, the adoption of this herbicide in a wide range of culture systems has led to the emergence of resistant weeds. Glyphosate has been widely used primarily on citrus in the Caribbean area, but a study of resistance in the Caribbean islands of Cuba and the Dominican Republic has never been carried out. Unfortunately, Parthenium hysterophorus has developed glyphosate-resistance in both islands, independently. The resistance level and mechanisms of different P. hysterophorus accessions (three collected in Cuba (Cu-R) and four collected in the Dominican Republic (Do-R) have been studied under greenhouse and laboratory conditions. In in vivo assays (glyphosate dose causing 50% reduction in above-ground vegetative biomass and survival), the resistance factor levels showed susceptible accessions (Cu-S ≥ Do-S), low-resistance accessions (Cu-R3 glyphosate (Cu-R1 ≥ Do-R1 > Do-R2 > Cu-R2 > Do-R3 > Do-R4 > Cu-R3 > Cu-S ≥ Do-S). Glyphosate was degraded to aminomethylphosphonic acid, glyoxylate and sarcosine by >88% in resistant accessions except in Cu-R3 and Do-R4 resistant accessions (51.12 and 44.21, respectively), whereas a little glyphosate (glyphosate rates. The R accessions showed values of between 0.026 and 0.21 μmol μg(-1) TSP protein min(-1) basal EPSPS activity values with respect to the S (0.024 and 0.025) accessions. The same trend was found in the EPSPS enzyme activity treated with glyphosate, where a higher enzyme activity inhibition (glyphosate μM) corresponded to greater resistance levels in P. hysterophorus accessions. One amino acid substitution was found at position 106 in EPSPS, consisting of a proline to serine change in Cu-R1, Do-R1 Do-R2. The above-mentioned results indicate that high resistance values are determined by the number of defense mechanisms (target-site and non

  19. Whey protein hydrolysate augments tendon and muscle hypertrophy independent of resistance exercise contraction mode

    DEFF Research Database (Denmark)

    Farup, Jean; Rahbek, S K; Vendelbo, M H

    2014-01-01

    In a comparative study, we investigated the effects of maximal eccentric or concentric resistance training combined with whey protein or placebo on muscle and tendon hypertrophy. 22 subjects were allocated into either a high-leucine whey protein hydrolysate + carbohydrate group (WHD...... or contraction mode effects. In conclusion, high-leucine whey protein hydrolysate augments muscle and tendon hypertrophy following 12 weeks of resistance training – irrespective of contraction mode....

  20. Deletions in a ribosomal protein-coding gene are associated with tigecycline resistance in Enterococcus faecium.

    Science.gov (United States)

    Niebel, Marc; Quick, Joshua; Prieto, Ana Maria Guzman; Hill, Robert L R; Pike, Rachel; Huber, Damon; David, Miruna; Hornsey, Michael; Wareham, David; Oppenheim, Beryl; Woodford, Neil; van Schaik, Willem; Loman, Nicholas

    2015-11-01

    Enterococcus faecium is an emerging nosocomial pathogen associated with antibiotic therapy in the hospital environment. Whole-genome sequences were determined for three pairs of related, consecutively collected E. faecium clinical isolates to determine putative mechanisms of resistance to tigecycline. The first isolates (1S, 2S and 3S) in each of the three pairs were sensitive to tigecycline [minimum inhibitory concentration (MIC) of 0.125 mg/L]. Following tigecycline therapy, the second isolate in each pair demonstrated increased resistance to tigecycline. Two isolates (1R and 2R) were resistant (MIC of 8 mg/L) and one isolate (3I) demonstrated reduced susceptibility (MIC of 0.5 mg/L). Mutations distinguishing each pair of sensitive and resistant isolates were determined through alignment to a reference genome and variant detection. In addition, a de novo assembly of each isolate genome was constructed to confirm mutations. A total of 16 mutations in eleven coding sequences were determined. Mutations in the rpsJ gene, which encodes a structural protein forming part of the 30S ribosomal subunit, were detected in each of the pairs. Mutations were in regions proximal to the predicted tigecycline-binding site. Predicted amino acid substitutions were detected in 1R and 3I. The resistant strains were additionally associated with deletions of 15 nucleotides (2R) and 3 nucleotides (1R). This study confirms that amino acid substitutions in rpsJ contribute towards reduced susceptibility to tigecycline and suggests that deletions may be required for tigecycline resistance in E. faecium.

  1. Exploring glycopeptide-resistance in Staphylococcus aureus: a combined proteomics and transcriptomics approach for the identification of resistance-related markers

    Directory of Open Access Journals (Sweden)

    Renzoni Adriana

    2006-11-01

    Full Text Available Abstract Background To unravel molecular targets involved in glycopeptide resistance, three isogenic strains of Staphylococcus aureus with different susceptibility levels to vancomycin or teicoplanin were subjected to whole-genome microarray-based transcription and quantitative proteomic profiling. Quantitative proteomics performed on membrane extracts showed exquisite inter-experimental reproducibility permitting the identification and relative quantification of >30% of the predicted S. aureus proteome. Results In the absence of antibiotic selection pressure, comparison of stable resistant and susceptible strains revealed 94 differentially expressed genes and 178 proteins. As expected, only partial correlation was obtained between transcriptomic and proteomic results during stationary-phase. Application of massively parallel methods identified one third of the complete proteome, a majority of which was only predicted based on genome sequencing, but never identified to date. Several over-expressed genes represent previously reported targets, while series of genes and proteins possibly involved in the glycopeptide resistance mechanism were discovered here, including regulators, global regulator attenuator, hyper-mutability factor or hypothetical proteins. Gene expression of these markers was confirmed in a collection of genetically unrelated strains showing altered susceptibility to glycopeptides. Conclusion Our proteome and transcriptome analyses have been performed during stationary-phase of growth on isogenic strains showing susceptibility or intermediate level of resistance against glycopeptides. Altered susceptibility had emerged spontaneously after infection with a sensitive parental strain, thus not selected in vitro. This combined analysis allows the identification of hundreds of proteins considered, so far as hypothetical protein. In addition, this study provides not only a global picture of transcription and expression adaptations

  2. Kinetic Ductility and Force-Spike Resistance of Proteins from Single-Molecule Force Spectroscopy.

    Science.gov (United States)

    Cossio, Pilar; Hummer, Gerhard; Szabo, Attila

    2016-08-23

    Ductile materials can absorb spikes in mechanical force, whereas brittle ones fail catastrophically. Here we develop a theory to quantify the kinetic ductility of single molecules from force spectroscopy experiments, relating force-spike resistance to the differential responses of the intact protein and the unfolding transition state to an applied mechanical force. We introduce a class of unistable one-dimensional potential surfaces that encompass previous models as special cases and continuously cover the entire range from ductile to brittle. Compact analytic expressions for force-dependent rates and rupture-force distributions allow us to analyze force-clamp and force-ramp pulling experiments. We find that the force-transmitting protein domains of filamin and titin are kinetically ductile when pulled from their two termini, making them resistant to force spikes. For the mechanostable muscle protein titin, a highly ductile model reconciles data over 10 orders of magnitude in force loading rate from experiment and simulation. Copyright © 2016 Biophysical Society. All rights reserved.

  3. Mapping Protein–Protein Interactions of the Resistance-Related Bacterial Zeta Toxin–Epsilon Antitoxin Complex (ε2ζ2 with High Affinity Peptide Ligands Using Fluorescence Polarization

    Directory of Open Access Journals (Sweden)

    María Isabel Fernández-Bachiller

    2016-07-01

    Full Text Available Toxin–antitoxin systems constitute a native survival strategy of pathogenic bacteria and thus are potential targets of antibiotic drugs. Here, we target the Zeta–Epsilon toxin–antitoxin system, which is responsible for the stable maintenance of certain multiresistance plasmids in Gram-positive bacteria. Peptide ligands were designed on the basis of the ε2ζ2 complex. Three α helices of Zeta forming the protein–protein interaction (PPI site were selected and peptides were designed conserving the residues interacting with Epsilon antitoxin while substituting residues binding intramolecularly to other parts of Zeta. Designed peptides were synthesized with an N-terminal fluoresceinyl-carboxy-residue for binding assays and provided active ligands, which were used to define the hot spots of the ε2ζ2 complex. Further shortening and modification of the binding peptides provided ligands with affinities <100 nM, allowing us to determine the most relevant PPIs and implement a robust competition binding assay.

  4. Electronegativity and intrinsic disorder of preeclampsia-related proteins.

    Science.gov (United States)

    Polanco, Carlos; Castañón-González, Jorge Alberto; Uversky, Vladimir N; Buhse, Thomas; Samaniego Mendoza, José Lino; Calva, Juan J

    2017-01-01

    Preeclampsia, hemorrhage, and infection are the leading causes of maternal death in underdeveloped countries. Since several proteins associated with preeclampsia are known, we conducted a computational study which evaluated the commonness and potential functionality of intrinsic disorder of these proteins and also made an attempt to characterize their origin. The origin of the preeclampsia-related proteins was assessed with a supervised technique, a Polarity Index Method (PIM), which evaluates the electronegativity of proteins based solely on their sequence. The commonness of intrinsic disorder was evaluated using several disorder predictors from the PONDR family, the charge-hydropathy plot (CH-plot) and cumulative distribution function (CDF) analyses, and using the MobiDB web-based tool, whereas potential functionality of intrinsic disorder was studied with the D2P2 resource and ANCHOR predictor of disorder-based binding sites, and the STRING tool was used to build the interactivity networks of the preeclampsia-related proteins. Peculiarities of the PIM-derived polar profile of the group of preeclampsia-related proteins were then compared with profiles of a group of lipoproteins, antimicrobial peptides, angiogenesis-related proteins, and the intrinsically disordered proteins. Our results showed a high graphical correlation between preeclampsia proteins, lipoproteins, and the angiogenesis proteins. We also showed that many preeclampsia-related proteins contain numerous functional disordered regions. Therefore, these bioinformatics results led us to assume that the preeclampsia proteins are highly associated with the lipoproteins group, and that some preeclampsia-related proteins contain significant amounts of functional disorders.

  5. Heat-resistant protein expression during germination of maize seeds under water stress.

    Science.gov (United States)

    Abreu, V M; Silva Neta, I C; Von Pinho, E V R; Naves, G M F; Guimarães, R M; Santos, H O; Von Pinho, R G

    2016-08-12

    Low water availability is one of the factors that limit agricultural crop development, and hence the development of genotypes with increased water stress tolerance is a challenge in plant breeding programs. Heat-resistant proteins have been widely studied, and are reported to participate in various developmental processes and to accumulate in response to stress. This study aimed to evaluate heat-resistant protein expression under water stress conditions during the germination of maize seed inbreed lines differing in their water stress tolerance. Maize seed lines 91 and 64 were soaked in 0, -0.3, -0.6, and -0.9 MPa water potential for 0, 6, 12, 18, and 24 h. Line 91 is considered more water stress-tolerant than line 64. The analysis of heat-resistant protein expression was made by gel electrophoresis and spectrophotometry. In general, higher expression of heat-resistant proteins was observed in seeds from line 64 subjected to shorter soaking periods and lower water potentials. However, in the water stress-tolerant line 91, a higher expression was observed in seeds that were subjected to -0.3 and -0.6 MPa water potentials. In the absence of water stress, heat-resistant protein expression was reduced with increasing soaking period. Thus, there was a difference in heat-resistant protein expression among the seed lines differing in water stress tolerance. Increased heat-resistant protein expression was observed in seeds from line 91 when subjected to water stress conditions for longer soaking periods.

  6. Structure-property studies on carbohydrate-derived polymers for use as protein-resistant biomaterials.

    Science.gov (United States)

    Metzke, Mark; Guan, Zhibin

    2008-01-01

    Here we describe structure-property studies on our carbohydrate-derived side-chain ether polymers as protein-resistant biomaterials. A series of side-chain ether polymers, including two polyesters and two polyamides, were prepared by condensation polymerization of monomers derived from simple carbohydrates. The two side-chain permethoxylated polyesters having different stereochemical repeating units demonstrate excellent resistance toward nonspecific protein adsorption as shown by surface plasmon resonance, indicating that the polymer stereochemistry does not have much effect on its protein-resistant properties. The introduction of amide bonds to polymer backbones leads to more pronounced effects. While the polymer degradation stability is significantly enhanced by replacing ester with amide linkages, the protein resistance for the polymer is greatly reduced by introduction of amide bonds. Finally, our results suggest that free hydroxyl and amide groups, while both are hydrogen-bond donors, seem to have different effects on protein resistant properties for polymers. It appears that free amide groups have more detrimental effect on protein resistance than free hydroxyl groups. These results show that the protein-resistant properties of this family of polymers can be tailored by modifying the backbone and side chain functionalities. In combination with the biodegradability and functionalizability, this family of carbohydrate-derived polymers shows promise as versatile biomaterials for biomedical applications.

  7. Protein-resistant polymer coatings obtained by matrix assisted pulsed laser evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Rusen, L. [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, PO Box MG-16, 077125, Magurele, Bucharest (Romania); Mustaciosu, C. [Horia Hulubei National Institute of Physics and Nuclear Engineering - IFIN HH, Magurele, Bucharest (Romania); Mitu, B.; Filipescu, M.; Dinescu, M. [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, PO Box MG-16, 077125, Magurele, Bucharest (Romania); Dinca, V., E-mail: dinali@nipne.ro [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, PO Box MG-16, 077125, Magurele, Bucharest (Romania)

    2013-08-01

    Adsorption of proteins and polysaccharides is known to facilitate microbial attachment and subsequent formation of biofilm on surfaces that ultimately results in its biofouling. Therefore, protein repellent modified surfaces are necessary to block the irreversible attachment of microorganisms. Within this context, the feasibility of using the Poly(ethylene glycol)-block-poly(ε-caprolactone) methyl ether (PEG-block-PCL Me) copolymer as potential protein-resistant coating was explored in this work. The films were deposited using Matrix Assisted Pulsed Laser Evaporation (MAPLE), a technique that allows good control of composition, thickness and homogeneity. The chemical and morphological characteristics of the films were examined using Fourier Transform Infrared Spectroscopy (FTIR), contact angle measurements and Atomic Force Microscopy (AFM). The FTIR data demonstrates that the functional groups in the MAPLE-deposited films remain intact, especially for fluences below 0.5 J cm{sup −2}. Optical Microscopy and AFM images show that the homogeneity and the roughness of the coatings are related to both laser parameters (fluence, number of pulses) and target composition. Protein adsorption tests were performed on the PEG-block-PCL Me copolymer coated glass and on bare glass surface as a control. The results show that the presence of copolymer as coating significantly reduces the adsorption of proteins.

  8. Protein-resistant polymer coatings obtained by matrix assisted pulsed laser evaporation

    Science.gov (United States)

    Rusen, L.; Mustaciosu, C.; Mitu, B.; Filipescu, M.; Dinescu, M.; Dinca, V.

    2013-08-01

    Adsorption of proteins and polysaccharides is known to facilitate microbial attachment and subsequent formation of biofilm on surfaces that ultimately results in its biofouling. Therefore, protein repellent modified surfaces are necessary to block the irreversible attachment of microorganisms. Within this context, the feasibility of using the Poly(ethylene glycol)-block-poly(ɛ-caprolactone) methyl ether (PEG-block-PCL Me) copolymer as potential protein-resistant coating was explored in this work. The films were deposited using Matrix Assisted Pulsed Laser Evaporation (MAPLE), a technique that allows good control of composition, thickness and homogeneity. The chemical and morphological characteristics of the films were examined using Fourier Transform Infrared Spectroscopy (FTIR), contact angle measurements and Atomic Force Microscopy (AFM). The FTIR data demonstrates that the functional groups in the MAPLE-deposited films remain intact, especially for fluences below 0.5 J cm-2. Optical Microscopy and AFM images show that the homogeneity and the roughness of the coatings are related to both laser parameters (fluence, number of pulses) and target composition. Protein adsorption tests were performed on the PEG-block-PCL Me copolymer coated glass and on bare glass surface as a control. The results show that the presence of copolymer as coating significantly reduces the adsorption of proteins.

  9. [The role of Cd-binding proteins and phytochelatins in the formation of cadmium resistance in Nicotiana plumbaginifolia cell lines].

    Science.gov (United States)

    Fenik, S I; Solodushko, V G; Kaliniak, T B; Blium, Ia B

    2007-01-01

    Nicotiana plumbaginifolia callus lines with the equal resistance to cadmium have been produced under different selective conditions--either without inhibition of the phytochelatin synthesis (line Cd-R) or in the presence of the inhibitor butionine sulfoximine (line Cd-Ri). The level of phytochelatin synthesis in the line Cd-R five-fold exceeded the control value and in the line Cd-Ri it was twice as much as in the control. It was shown that in the control line mainly three cadmium-binding proteins are expressed of the molecular weihgts 41, 34 and 19 kD. The common feature of the both resistant lines is the expression of the cadmium-binding proteins of 40, 37 and 19 kD. The resistant lines differ with respect to the synthesis of relatively low-molecular cadmium-binding proteins. The proteins of the molecular weights 12.5, 11.5 and 9 kD are expressed in the line Cd-R, while the proteins of 13 and 10 kD are expressed in the line Cd-Ri. It was supposed that both the phytochelatins and the Cd-binding proteins contribute to the resisitance of N. plumbaginifolia callus lines to cadmium and the lack of the phytochelatins can be equilibrated by the changes in the low-molecular Cd-binding protein synthesis.

  10. Structure, function and subcellular localization of the potato Resistance protein Rx1

    NARCIS (Netherlands)

    Slootweg, E.J.

    2009-01-01

    Resistance proteins are part of the plant’s immune system and mediate a defence response upon recognizing their cognate pathogens. They are thought to be present in the cell as part of a larger protein complex. The modular architecture of R proteins suggests that they form a scaffold for various int

  11. TIMP-1 increases expression and phosphorylation of proteins associated with drug resistance in breast cancer cells

    DEFF Research Database (Denmark)

    Hekmat, Omid; Munk, Stephanie; Fogh, Louise

    2013-01-01

    Tissue inhibitor of metalloproteinase 1 (TIMP-1) is a protein with a potential biological role in drug resistance. To elucidate the unknown molecular mechanisms underlying the association between high TIMP-1 levels and increased chemotherapy resistance, we employed SILAC-based quantitative mass...... may explain the resistance phenotype to topoisomerase inhibitors that was observed in cells with high TIMP-1 levels. Pathway analysis showed an enrichment of proteins from functional categories such as apoptosis, cell cycle, DNA repair, transcription factors, drug targets and proteins associated...... with drug resistance or sensitivity and drug transportation. The NetworKIN algorithm predicted the protein kinases CK2a, CDK1, PLK1 and ATM as likely candidates involved in the hyper-phosphorylation of the topoisomerases. Up-regulation of protein and/or phosphorylation levels of topoisomerases in TIMP-1...

  12. Salivary gland proteome analysis reveals modulation of anopheline unique proteins in insensitive acetylcholinesterase resistant Anopheles gambiae mosquitoes.

    Directory of Open Access Journals (Sweden)

    Sylvie Cornelie

    Full Text Available Insensitive acetylcholinesterase resistance due to a mutation in the acetylcholinesterase (ace encoding ace-1 gene confers cross-resistance to organophosphate and carbamate insecticides in Anopheles gambiae populations from Central and West Africa. This mutation is associated with a strong genetic cost revealed through alterations of some life history traits but little is known about the physiological and behavioural changes in insects bearing the ace-1(R allele. Comparative analysis of the salivary gland contents between An. gambiae susceptible and ace-1(R resistant strains was carried out to charaterize factors that could be involved in modifications of blood meal process, trophic behaviour or pathogen interaction in the insecticide-resistant mosquitoes. Differential analysis of the salivary gland protein profiles revealed differences in abundance for several proteins, two of them showing major differences between the two strains. These two proteins identified as saglin and TRIO are salivary gland-1 related proteins, a family unique to anopheline mosquitoes, one of them playing a crucial role in salivary gland invasion by Plasmodium falciparum sporozoites. Differential expression of two other proteins previously identified in the Anopheles sialome was also observed. The differentially regulated proteins are involved in pathogen invasion, blood feeding process, and protection against oxidation, relevant steps in the outcome of malaria infection. Further functional studies and insect behaviour experiments would confirm the impact of the modification of the sialome composition on blood feeding and pathogen transmission abilities of the resistant mosquitoes. The data supports the hypothesis of alterations linked to insecticide resistance in the biology of the primary vector of human malaria in Africa.

  13. Label-free SRM-based relative quantification of antibiotic resistance mechanisms in Pseudomonas aeruginosa clinical isolates

    Directory of Open Access Journals (Sweden)

    Yannick eCharretier

    2015-02-01

    Full Text Available Both acquired and intrinsic mechanisms play a crucial role in Pseudomonas aeruginosa antibiotic resistance. Many clinically relevant resistance mechanisms result from changes in gene expression, namely multidrug efflux pump overproduction, AmpC beta-lactamase induction or derepression, and inactivation or repression of the carbapenem-specific porin OprD. Changes in gene expression are usually assessed using reverse-transcription quantitative real-time PCR (RT-qPCR assays. Here, we evaluated label-free Selected Reaction Monitoring (SRM-based mass spectrometry to directly quantify proteins involved in antibiotic resistance. We evaluated the label-free SRM using a defined set of P. aeruginosa isolates with known resistance mechanisms and compared it against RT-qPCR. Referring to efflux systems, we found a more robust relative quantification of antibiotic resistance mechanisms by SRM than RT-qPCR. The SRM-based approach was applied to a set of clinical P. aeruginosa isolates to detect antibiotic resistance proteins. This multiplexed SRM-based approach is a rapid and reliable method for the simultaneous detection and quantification of resistance mechanisms and we demonstrate its relevance for antibiotic resistance prediction.

  14. Differentially expressed proteins in fluconazole-susceptible and fluconazole-resistant isolates of Candida glabrata.

    Science.gov (United States)

    Shen, Yinzhong; Zhang, Lijun; Jia, Xiaofang; Zhang, Yongxin; Lu, Hongzhou

    2015-06-01

    The current study aimed to identify the differences presented in the proteome of fluconazole-susceptible isolates of Candida glabrata compared to those with fluconazole-resistant ones. Two-dimensional differential gel electrophoresis was applied to identify proteins that were differentially expressed in fluconazole-susceptible and fluconazole-resistant isolates of C. glabrata. Eight proteins including aspartyl-tRNA synthetase, translation elongation factor 3, 3-phosphoglycerate kinase, ribosomal protein L5, coproporphyrinogen III oxidase, pyruvate kinase, G-beta like protein, and F1F0-ATPase alpha subunit were found to be more abundantly represented, while four proteins including vitamin B12-(cobalamin)-independent isozyme of methionine synthase, microtubule-associated protein, adenylosuccinate synthetase, and aldose reductase were found to be less abundantly represented in fluconazole-resistant strains versus those with fluconazole-susceptible ones. These differentially expressed proteins were primarily associated with energy metabolism, stress response, and macromolecule synthesis. Proteins associated with energy metabolism, stress response, and macromolecule synthesis may play a role in the development of fluconazole resistance in the clinical isolates of C. glabrata. Multiple different mechanisms are involved in the development of fluconazole resistance in C. glabrata. These findings provide a scientific basis for discovering new genes and mechanisms associated with fluconazole resistance in C. glabrata.

  15. Isolation and Identification of Alicyclobacillus with High Dipicolinic Acid and Heat Resistant Proteins from Mango Juice

    Directory of Open Access Journals (Sweden)

    Hamid Reza Akhbariyoon

    2016-10-01

    Full Text Available Background and Objectives: Microbial spoilage of juices and industries related with Alicyclobacillus are considerable international issues. This spore-forming bacterium causes changes in juices odor and taste. The isolation and identification of Alicyclobacillus contamination in juice producing and packaging industries has an essential role in the prevention and control of this type of spoilage bacterium in HACCP (Hazard analysis and critical control points manner.Materials and Methods: A thermo-acidophilic, non-pathogenic and sporeforming bacterium was isolated from mango juice. Preliminary identification of the isolates was based on morphological, biochemical and physiological properties. Identification at species level was made by PCR amplification. The influence of temperature in the range of 25-65°C in the growth of bacterium and in the range of 80-120°C in spore-resistant and heat resistant proteins was investigated and compared with other spore producing bacteria.Results and Conclusion: Phylogenetic analysis of the 16S rRNA gene sequencing indicated that the isolated strain constituted a distinct lineage in the Alicyclobacillus cluster and submitted to NCBI with access number Alicyclobacillus HRM-5 KM983424.1. The spores resisted 110°C for 3 h, and produced 28% dipicolinic acid more comparable to Bacillus licheniformis. Also they could produce 0.69 mg heat resistance protein after 1.5 h treatment in 100°C. The results showed that this strain could have biotechnological applications.Conflict of interests: The authors declare no conflict of interest.

  16. Stimulation of Myofibrillar Protein Synthesis in Hindlimb Suspended Rats by Resistance Exercise and Growth Hormone

    Science.gov (United States)

    Linderman, Jon K.; Whittall, Justen B.; Gosselink, Kristin L.; Wang, Tommy J.; Mukku, Venkat R.; Booth, Frank W.; Grindeland, Richard E.

    1995-01-01

    The objective of this study was to determine the ability of a single bout of resistance exercise alone or in combination with recombinant human growth hormone (rhGH) to stimulate myofibrillar protein synthesis (Ks) in hindlimb suspended (HLS) adult female rats. Plantar flexor muscles were stimulated with resistance exercise, consisting of 10 repetitions of ladder climbing on a 1 m grid (85 deg.), carrying an additional 50% of their body weight attached to their tails. Saline or rhGH (1 mg/kg) was administered 30' prior to exercise, and Ks was determined with a constant infusion of H-3-Leucine at 15', 60', 180', and 360' following exercise. Three days of HLS depressed Ks is approx. equal to 65% and 30-40% in the soleus and gastrocnemius muscles, respectively (p is less than or equal to 0.05). Exercise increased soleus Ks in saline-treated rats 149% 60' following exercise (p less than or equal to 0.05), decaying to that of non-exercised animals during the next 5 hours. Relative to suspended, non-exercised rats rhGH + exercise increased soleus Ks 84%, 108%, and 72% at 15', 60' and 360' following exercise (p is less than or equal to 0.05). Gastrocnemius Ks was not significantly increased by exercise or the combination of rhGH and exercise up to 360' post-exercise. Results from this study indicate that resistance exercise stimulated Ks 60' post-exercise in the soleus of HLS rats, with no apparent effect of rhGH to enhance or prolong exercise-induced stimulation. Results suggests that exercise frequency may be important to maintenance of the slow-twitch soleus during non-weightbearing, but that the ability of resistance exercise to maintain myofibrillar protein content in the gastrocnemius of hindlimb suspended rats cannot be explained by acute stimulation of synthesis.

  17. Coexistence of protease sensitive and resistant prion protein in 129VV homozygous sporadic Creutzfeldt–Jakob disease: a case report

    Directory of Open Access Journals (Sweden)

    Rodríguez-Martínez Ana B

    2012-10-01

    Full Text Available Abstract Introduction The coexistence of different molecular types of classical protease-resistant prion protein in the same individual have been described, however, the simultaneous finding of these with the recently described protease-sensitive variant or variably protease-sensitive prionopathy has, to the best of our knowledge, not yet been reported. Case presentation A 74-year-old Caucasian woman showed a sporadic Creutzfeldt–Jakob disease clinical phenotype with reactive depression, followed by cognitive impairment, akinetic-rigid Parkinsonism with pseudobulbar syndrome and gait impairment with motor apraxia, visuospatial disorientation, and evident frontal dysfunction features such as grasping, palmomental reflex and brisk perioral reflexes. She died at age 77. Neuropathological findings showed: spongiform change in the patient’s cerebral cortex, striatum, thalamus and molecular layer of the cerebellum with proteinase K-sensitive synaptic-like, dot-like or target-like prion protein deposition in the cortex, thalamus and striatum; proteinase K-resistant prion protein in the same regions; and elongated plaque-like proteinase K-resistant prion protein in the molecular layer of the cerebellum. Molecular analysis of prion protein after proteinase K digestion revealed decreased signal intensity in immunoblot, a ladder-like protein pattern, and a 71% reduction of PrPSc signal relative to non-digested material. Her cerebellum showed a 2A prion protein type largely resistant to proteinase K. Genotype of polymorphism at codon 129 was valine homozygous. Conclusion Molecular typing of prion protein along with clinical and neuropathological data revealed, to the best of our knowledge, the first case of the coexistence of different protease-sensitive prion proteins in the same patient in a rare case that did not fulfill the current clinical diagnostic criteria for either probable or possible sporadic Creutzfeldt–Jakob disease. This highlights the

  18. Copper resistance in Pseudomonas syringae mediated by periplasmic and outer membrane proteins.

    OpenAIRE

    Cha, J S; Cooksey, D A

    1991-01-01

    Copper-resistant strains of Pseudomonas syringae pathovar tomato accumulate copper and develop blue colonies on copper-containing media. Three of the protein products of the copper-resistance operon (cop) were characterized to provide an understanding of the copper-resistance mechanism and its relationship to copper accumulation. The Cop proteins, CopA (72 kDa), CopB (39 kDa), and CopC (12 kDa), were produced only under copper induction. CopA and CopC were periplasmic proteins and CopB was an...

  19. Induced resistance in Arabidopsis and radish; involvement of PR proteins

    OpenAIRE

    HOFFLAND, E.; Pieterse, C. M. J.; Bik, L.; Pelt, J.A. van

    1995-01-01

    This paper demonstrates that Pseudomonas fluorescens strain WCS417 and salicylic acid can induce systemic resistance in radish and Arabidopsis thaliana against Fusarium oxysporum. In neither of the two plant species this induction is associated with induction of PRs. This indicates that PR-accumulation is not a prerequisite for induction of systemic resistance.

  20. [Evaluation of penicillin-binding protein genotypes in penicillin susceptible and resistant Streptococcus pneumoniae isolates].

    Science.gov (United States)

    Aslan, Gönül; Tezcan, Seda; Delialioğlu, Nuran; Aydın, Fatma Esin; Kuyucu, Necdet; Emekdaş, Gürol

    2012-04-01

    Penicillin-binding proteins (PBPs) are the natural targets of beta-lactam antibiotics and mutations in pbp1a, pbp2b, and pbp2x genes, which encode PBPs, are responsible for resistance to beta-lactams in Streptococcus pneumoniae. In the present study, we intended to determine how often the common mutation patterns occurred within the pbp1a, pbp2b, and pbp2x PBP gene regions and evaluate the PBP genotype mutations which were associated with penicillin resistance in several penicillin-susceptible and - resistant S.pneumoniae isolates in Mersin, Turkey. A total of 62 S.pneumoniae strains isolated from different clinical specimens (32 nasopharyngeal swab, 16 sputum, 3 blood, 3 wound, 2 cerebrospinal fluids and one of each urine, abscess, bronchoalveolar lavage, conjunctival swab, tracheal aspirate, middle ear effusion) were included in the study. Penicillin susceptibilities of the isolates were searched by disc diffusion and E-test methods, and 23 of them were identified as susceptible, 31 were intermediate susceptible, and eight were resistant to penicillin. A rapid DNA extraction procedure was performed for the isolation of nucleic acids from the strains. Distribution of PBP gene mutations in pbp1a, pbp2b, and pbp2x gene regions related to penicillin resistance was determined by using a wild-type specific polymerase chain reaction (PCR) based technique. PBP gene alterations of those isolates were also evaluated in relation to penicillin susceptibility and resistance patterns. Twenty two (95.7%) of 23 penicillin-susceptible S.pneumoniae isolates exhibited no mutation in the three PBP genes (pbp1a, pbp2x, and pbp 2b), while 1 (4.3%) of these harbored mutations in all of the three PBP genes. The penicillin-intermediate susceptible S.pneumoniae isolates exhibited various combinations of mutations. One (3.2%) of 31 penicillin-intermediate susceptible isolates exhibited no mutation in the three PBP genes, while 22 (71%) of them yielded mutations in all of the three PBP

  1. THE CLINICAL EXPRESSION OF HEREDITARY PROTEIN-C AND PROTEIN-S DEFICIENCY - A RELATION TO CLINICAL THROMBOTIC RISK-FACTORS AND TO LEVELS OF PROTEIN-C AND PROTEIN-S

    NARCIS (Netherlands)

    HENKENS, CMA; VANDERMEER, J; HILLEGE, JL; BOM, VJJ; HALIE, MR; van der Schaaf, W

    1993-01-01

    We investigated 103 first-degree relatives of 13 unrelated protein C or protein S deficient patients to assess the role of additional thrombotic risk factors and of protein C and protein S levels in the clinical expression of hereditary protein C and protein S deficiency. Fifty-seven relatives were

  2. Leucine supplementation improves acquired growth hormone resistance in rats with protein-energy malnutrition.

    Directory of Open Access Journals (Sweden)

    Xuejin Gao

    Full Text Available Protein-energy malnutrition (PEM can lead to growth hormone (GH resistance. Leucine supplementation diets have been shown to increase protein synthesis in muscles. Our study aimed at investigating if long-term leucine supplementation could modulate GH-insulin-like growth factor (IGF-1 system function and mammalian target of rapamycin (mTOR-related signal transduction in skeletal muscles in a rat model of severe malnutrition.Male Sprague-Dawley rats (n = 50; weight, 302 ± 5 g were divided into 5 treatment groups, including 2 control groups (a normal control group that was fed chow and ad libitum water [CON, n = 10] and a malnourished control group [MC, n = 10] that was fed a 50% chow diet. After undergoing a weight loss stage for 4 weeks, rats received either the chow diet (MC-CON, n = 10, the chow diet supplemented with low-dose leucine (MC-L, n = 10, or the chow diet supplemented with high-dose leucine (MC-H, n = 10 for 2 weeks. The muscle masses of the gastrocnemius, soleus, and extensor digitorum longus were significantly reduced in the MC group. Re-feeding increased muscle mass, especially in the MC-L and MC-H groups. In the MC group, serum IGF-1, IGF-binding protein (IGFBP-3, and hepatic growth hormone receptor (GHR levels were significantly decreased and phosphorylation of the downstream anabolic signaling effectors protein kinase B (Akt, mTOR, and ribosomal protein S6 kinase 1 (S6K1 were significantly lower than in other groups. However, serum IGF-1 and IGF binding protein (IGFBP-3 concentrations and hepatic growth hormone receptor (GHR levels were significantly higher in the MC-L and MC-H groups than in the MC-CON group, and serum IGFBP-1 levels was significantly reduced in the MC-L and MC-H groups. These changes were consistent with those observed for hepatic mRNA expression levels. Phosphorylation of the downstream anabolic signaling effectors Akt, mTOR, and S6K1 were also significantly higher in the MC-L and MC-H groups than in the

  3. Differentially expressed proteins in human MCF-7 breast cancer cells sensitive and resistant to paclitaxel.

    Science.gov (United States)

    Pavlíková, Nela; Bartoňová, Irena; Balušíková, Kamila; Kopperova, Dana; Halada, Petr; Kovář, Jan

    2015-04-10

    Resistance of cancer cells to chemotherapeutic agents is one of the main causes of treatment failure. In order to detect proteins potentially involved in the mechanism of resistance to taxanes, we assessed differences in protein expression in MCF-7 breast cancer cells that are sensitive to paclitaxel and in the same cells with acquired resistance to paclitaxel (established in our lab). Proteins were separated using two-dimensional electrophoresis. Changes in their expression were determined and proteins with altered expression were identified using mass spectrometry. Changes in their expression were confirmed using western blot analysis. With these techniques, we found three proteins expressed differently in resistant MCF-7 cells, i.e., thyroid hormone-interacting protein 6 (TRIP6; upregulated to 650%), heat shock protein 27 (HSP27; downregulated to 50%) and cathepsin D (downregulated to 28%). Silencing of TRIP6 expression by specific siRNA leads to decreased number of grown resistant MCF-7 cells. In the present study we have pointed at some new directions in the studies of the mechanism of resistance to paclitaxel in breast cancer cells.

  4. High throughput atmospheric pressure plasma-induced graft polymerization for identifying protein-resistant surfaces.

    Science.gov (United States)

    Gu, Minghao; Kilduff, James E; Belfort, Georges

    2012-02-01

    Three critical aspects of searching for and understanding how to find highly resistant surfaces to protein adhesion are addressed here with specific application to synthetic membrane filtration. They include the (i) discovery of a series of previously unreported monomers from a large library of monomers with high protein resistance and subsequent low fouling characteristics for membrane ultrafiltration of protein-containing fluids, (ii) development of a new approach to investigate protein-resistant mechanisms from structure-property relationships, and (iii) adaptation of a new surface modification method, called atmospheric pressure plasma-induced graft polymerization (APP), together with a high throughput platform (HTP), for low cost vacuum-free synthesis of anti-fouling membranes. Several new high-performing chemistries comprising two polyethylene glycol (PEG), two amines and one zwitterionic monomers were identified from a library (44 commercial monomers) of five different classes of monomers as strong protein-resistant monomers. Combining our analysis here, using the Hansen solubility parameters (HSP) approach, and data from the literature, we conclude that strong interactions with water (hydrogen bonding) and surface flexibility are necessary for producing the highest protein resistance. Superior protein-resistant surfaces and subsequent anti-fouling performance was obtained with the HTP-APP as compared with our earlier HTP-photo graft-induced polymerization (PGP).

  5. Increased activator protein 1 activity as well as resistance to heat-induced radiosensitization, hydrogen peroxide, and cisplatin are inhibited by indomethacin in oxidative stress-resistant cells.

    Science.gov (United States)

    Bradbury, C M; Locke, J E; Wei, S J; Rene, L M; Karimpour, S; Hunt, C; Spitz, D R; Gius, D

    2001-04-15

    It has been established that tumor cells develop resistance to a variety of therapeutic agents after multiple exposures to these agents/drugs. Many of these therapeutic agents also appear to increase the activity of transcription factors, such as activator protein 1 (AP-1), believed to be involved in cellular responses to oxidative stress. Therefore, we hypothesized that cellular resistance to cancer therapeutic agents may involve the increased activity of transcription factors that govern resistance to oxidative stress, such as AP-1. To investigate this hypothesis, a previously characterized cisplatin, hyperthermia, and oxidative stress-resistant Chinese hamster fibroblast cell line, OC-14, was compared to the parental HA-1 cell line. Electrophoretic mobility shift and Western blot assays performed on extracts isolated from OC-14 cells demonstrated a 10-fold increase in constitutive AP-1 DNA-binding activity as well as increased constitutive c-Fos and c-Jun immunoreactive protein relative to HA-1 cells. Treatment of OC-14 cells with indomethacin inhibited constitutive increases in AP-1 DNA-binding activity and c-Fos/c-Jun-immunoreactive protein levels. Clonogenic survival assays demonstrated that pretreatment with indomethacin, at concentrations that inhibited AP-1 activity, significantly reduced the resistance of OC-14 cells to heat-induced radiosensitization, hydrogen peroxide, and cisplatin. These results demonstrate a relationship between increases in AP-1 DNA-binding activity and increased cellular resistance to cancer therapeutic agents and oxidative stress that is inhibited by indomethacin. These results support the hypothesis that inhibition of AP-1 activity with nonsteroidal anti-inflammatory drugs, such as indomethacin, may represent a useful adjuvant to cancer therapy.

  6. Cloning and Expression Analysis of Downy Mildew Resistance-Related cDNA Sequences in Melon

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Melon downy mildew caused by Pseudoperonospora cubensis leads to significant losses in melon yields worldwide.Reverse-transcription Polymerase Chain Reaction (RT-PCR) was performed using cDNAs as templates from melonHuangdanzi induced with fungus Pseudoperonospora cubensis, and degenerate primers designed based on the conserved amino acid sequences of known plant disease-resistance genes. A polymorphic cDNA fragment which we named mp-19was cloned and sequenced. The Open Reading Frame (ORF) of this product comprised of 510 base pairs which encodes DNA or RNA-binding protein with 170 amino acids. The putative amino acid sequence of mp-19 appeared highly homologous with those of NBS-type resistant-genes isolated from other plants. Southern blot indicated that the melon genome contained more than 3 copies of mp-19. The obvious expression differences detected by semi-quantitative RTPCR could be observed between resistant-line Huangdanzi and susceptible-line Jiashi after Pseudoperonospora cubensis infection, which implied that mp-19 gene may be related to the resistance of downy mildew in melon.

  7. PSSARD: protein sequence-structure analysis relational database.

    Science.gov (United States)

    Guruprasad, Kunchur; Srikanth, K; Babu, A V N

    2005-09-15

    We have implemented a relational database comprising a representative dataset of amino acid sequences and their associated secondary structure. The representative amino acid sequences were selected according to the PDB_SELECT program by choosing proteins corresponding to protein crystal structure data deposited in the protein data bank that share less than 25% overall pair-wise sequence identity. The secondary structure was extracted from the protein data bank website. The information content in the database includes the protein description, PDB code, crystal structure resolution, total number of amino acid residues in the protein chain, amino acid sequence, secondary structure conformation and its summary. The database is freely accessible from the website mentioned below and is useful to query on any of the above fields. The database is particularly useful to quickly retrieve amino acid sequences that are compatible to any super-secondary structure conformation from several proteins simultaneously.

  8. Prion protein: structural features and related toxicity

    Institute of Scientific and Technical Information of China (English)

    Ping Ping Hu; Cheng Zhi Huang

    2013-01-01

    Transmissible spongiform encephalopathies,or prion diseases,is a group of infectious neurodegenerative disorders.The conformational conversion from cellular form (PrPC) to disease-causing isoform (PrPSc) is considered to be the most important and remarkable event in these diseases,while accumulation of PrPSc is thought to be the main reason for cell death,inflammation and spongiform degeneration observed in infected individuals.Although these rare but unique neurodegenerative disorders have attracted much attention,there are still many questions that remain to be answered.Knowledge of the scrapie agent structures and the toxic species may have significance for understanding the causes of the diseases,and could be helpful for rational design of novel therapeutic and diagnostic methods.In this review,we summarized the available experimental evidence concerning the relationship among the structural features,aggregation status of misfolded PrP and related neurotoxicity in the course of prion diseases development.In particular,most data supports the idea that the smaller oligomeric PrPSc aggregates,rather than the mature amyloid fibers,exhibit the highest toxicity to the host.

  9. Timing of postexercise protein intake is important for muscle hypertrophy with resistance training in elderly humans

    DEFF Research Database (Denmark)

    Esmarck, Birgitte; Olsen, Steen Schytte

    2001-01-01

    1. Age-associated loss of skeletal muscle mass and strength can partly be counteracted by resistance training, causing a net synthesis of muscular proteins. Protein synthesis is influenced synergistically by postexercise amino acid supplementation, but the importance of the timing of protein intake...... remains unresolved. 2. The study investigated the importance of immediate (P0) or delayed (P2) intake of an oral protein supplement upon muscle hypertrophy and strength over a period of resistance training in elderly males. 3. Thirteen men (age, 74 ± 1 years; body mass index (BMI), 25 ± 1 kg m−2 (means...... %, respectively (P important...

  10. Effect of resistance exercise contraction mode and protein supplementation on members of the STARS signalling pathway.

    Science.gov (United States)

    Vissing, Kristian; Rahbek, Stine K; Lamon, Severine; Farup, Jean; Stefanetti, Renae J; Wallace, Marita A; Vendelbo, Mikkel H; Russell, Aaron

    2013-08-01

    The striated muscle activator of Rho signalling (STARS) pathway is suggested to provide a link between external stress responses and transcriptional regulation in muscle. However, the sensitivity of STARS signalling to different mechanical stresses has not been investigated. In a comparative study, we examined the regulation of the STARS signalling pathway in response to unilateral resistance exercise performed as either eccentric (ECC) or concentric (CONC) contractions as well as prolonged training; with and without whey protein supplementation. Skeletal muscle STARS, myocardian-related transcription factor-A (MRTF-A) and serum response factor (SRF) mRNA and protein, as well as muscle cross-sectional area and maximal voluntary contraction, were measured. A single-bout of exercise produced increases in STARS and SRF mRNA and decreases in MRTF-A mRNA with both ECC and CONC exercise, but with an enhanced response occurring following ECC exercise. A 31% increase in STARS protein was observed exclusively after CONC exercise (P exercise (P hypertrophy and produced increases in MRTF-A protein of 125% and 99%, respectively (P exercise provides an acute stimulation of the STARS pathway that is contraction mode dependent. The responses to acute exercise were more pronounced than responses to accumulated training, suggesting that STARS signalling is primarily involved in the initial phase of exercise-induced muscle adaptations.

  11. Altered protein expression in gestational diabetes mellitus placentas provides insight into insulin resistance and coagulation/fibrinolysis pathways.

    Directory of Open Access Journals (Sweden)

    Bin Liu

    Full Text Available OBJECTIVE: To investigate the placental proteome differences between pregnant women complicated with gestational diabetes mellitus (GDM and those with normal glucose tolerance (NGT. METHODS: We used two-dimensional electrophoresis (2DE to separate and compare placental protein levels from GDM and NGT groups. Differentially expressed proteins between the two groups were identified by MALDI-TOF/TOF mass spectrometry and further confirmed by Western blotting. The mRNA levels of related proteins were measured by realtime RT-PCR. Immunohistochemistry (IHC was performed to examine the cellular location of the proteins expressed in placenta villi. RESULTS: Twenty-one protein spots were differentially expressed between GDM and NGT placenta villi in the tested samples, fifteen of which were successfully identified by mass spectrometry. The molecular functions of these differentially expressed proteins include blood coagulation, signal transduction, anti-apoptosis, ATP binding, phospholipid binding, calcium ion binding, platelet activation, and tryptophan-tRNA ligase activity. Both protein and mRNA levels of Annexin A2, Annexin A5 and 14-3-3 protein ζ/δ were up-regulated, while the expression of the Ras-related protein Rap1A was down-regulated in the GDM placenta group. CONCLUSION: Placenta villi derived from GDM pregnant women exhibit significant proteome differences compared to those of NGT mothers. The identified differentially expressed proteins are mainly associated with the development of insulin resistance, transplacental transportation of glucose, hyperglucose-mediated coagulation and fibrinolysis disorders in the GDM placenta villi.

  12. Light-load resistance exercise increases muscle protein synthesis and hypertrophy signaling in elderly men.

    Science.gov (United States)

    Agergaard, Jakob; Bülow, Jacob; Jensen, Jacob K; Reitelseder, Søren; Drummond, Micah J; Schjerling, Peter; Scheike, Thomas; Serena, Anja; Holm, Lars

    2017-04-01

    The present study investigated whether well-tolerated light-load resistance exercise (LL-RE) affects skeletal muscle fractional synthetic rate (FSR) and anabolic intracellular signaling as a way to counteract age-related loss of muscle mass. Untrained healthy elderly (>65-yr-old) men were subjected to 13 h of supine rest. After 2.5 h of rest, unilateral LL-RE, consisting of leg extensions (10 sets, 36 repetitions) at 16% of 1 repetition maximum (RM), was conducted. Subsequently, the subjects were randomized to oral intake of 4 g of whey protein per hour (PULSE, n = 10), 28 g of whey protein at 0 h and 12 g of whey protein at 7 h postexercise (BOLUS, n = 10), or 4 g of maltodextrin per hour (placebo, n = 10). Quadriceps muscle biopsies were taken at 0, 3, 7, and 10 h postexercise from the resting and the exercised leg of each subject. Myofibrillar FSR and activity of select targets from the mechanistic target of rapamycin complex 1-signaling cascade were analyzed from the biopsies. LL-RE increased myofibrillar FSR compared with the resting leg throughout the 10-h postexercise period. Phosphorylated (T308) AKT expression increased in the exercised leg immediately after exercise. This increase persisted in the placebo group only. Levels of phosphorylated (T37/46) eukaryotic translation initiation factor 4E-binding protein 1 increased throughout the postexercise period in the exercised leg in the placebo and BOLUS groups and peaked at 7 h. In all three groups, phosphorylated (T56) eukaryotic elongation factor 2 decreased in response to LL-RE. We conclude that resistance exercise at only 16% of 1 RM increased myofibrillar FSR, irrespective of nutrient type and feeding pattern, which indicates an anabolic effect of LL-RE in elderly individuals. This finding was supported by increased signaling for translation initiation and translation elongation in response to LL-RE. Copyright © 2017 the American Physiological Society.

  13. A β-hairpin-binding protein for three different disease-related amyloidogenic proteins.

    Science.gov (United States)

    Shaykhalishahi, Hamed; Mirecka, Ewa A; Gauhar, Aziz; Grüning, Clara S R; Willbold, Dieter; Härd, Torleif; Stoldt, Matthias; Hoyer, Wolfgang

    2015-02-01

    Amyloidogenic proteins share a propensity to convert to the β-structure-rich amyloid state that is associated with the progression of several protein-misfolding disorders. Here we show that a single engineered β-hairpin-binding protein, the β-wrapin AS10, binds monomers of three different amyloidogenic proteins, that is, amyloid-β peptide, α-synuclein, and islet amyloid polypeptide, with sub-micromolar affinity. AS10 binding inhibits the aggregation and toxicity of all three proteins. The results demonstrate common conformational preferences and related binding sites in a subset of the amyloidogenic proteins. These commonalities enable the generation of multispecific monomer-binding agents.

  14. Benchmarking human protein complexes to investigate drug-related systems and evaluate predicted protein complexes.

    Directory of Open Access Journals (Sweden)

    Min Wu

    Full Text Available Protein complexes are key entities to perform cellular functions. Human diseases are also revealed to associate with some specific human protein complexes. In fact, human protein complexes are widely used for protein function annotation, inference of human protein interactome, disease gene prediction, and so on. Therefore, it is highly desired to build an up-to-date catalogue of human complexes to support the research in these applications. Protein complexes from different databases are as expected to be highly redundant. In this paper, we designed a set of concise operations to compile these redundant human complexes and built a comprehensive catalogue called CHPC2012 (Catalogue of Human Protein Complexes. CHPC2012 achieves a higher coverage for proteins and protein complexes than those individual databases. It is also verified to be a set of complexes with high quality as its co-complex protein associations have a high overlap with protein-protein interactions (PPI in various existing PPI databases. We demonstrated two distinct applications of CHPC2012, that is, investigating the relationship between protein complexes and drug-related systems and evaluating the quality of predicted protein complexes. In particular, CHPC2012 provides more insights into drug development. For instance, proteins involved in multiple complexes (the overlapping proteins are potential drug targets; the drug-complex network is utilized to investigate multi-target drugs and drug-drug interactions; and the disease-specific complex-drug networks will provide new clues for drug repositioning. With this up-to-date reference set of human protein complexes, we believe that the CHPC2012 catalogue is able to enhance the studies for protein interactions, protein functions, human diseases, drugs, and related fields of research. CHPC2012 complexes can be downloaded from http://www1.i2r.a-star.edu.sg/xlli/CHPC2012/CHPC2012.htm.

  15. Related Factors of Insulin Resistance in Korean Children: Adiposity and Maternal Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Kang-Sook Lee

    2011-12-01

    Full Text Available Increased adiposity and unhealthy lifestyle augment the risk for type 2 diabetes in children with familial predisposition. Insulin resistance (IR is an excellent clinical marker for identifying children at high risk for type 2 diabetes. This study was conducted to investigate parental, physiological, behavioral and socio-economic factors related to IR in Korean children. This study is a cross-sectional study using data from 111 children aged 7 years and their parents. Homeostasis model assessment of insulin resistance (HOMA-IR was calculated using fasting glucose and insulin level as a marker of IR. All children’s adiposity indices (r = 0.309–0.318, all P-value = 0.001 and maternal levels of fasting insulin (r = 0.285, P-value = 0.003 and HOMA-IR (r = 0.290, P-value = 0.002 were positively correlated with children’s HOMA-IR level. There was no statistical difference of children’s HOMA-IR level according to children’s lifestyle habits and socioeconomic status of families. An increase of 1 percentage point in body fat was related to 2.7% increase in children’s HOMA-IR (P-value < 0.001 and an increase of 1% of maternal level of HOMA-IR was related to 0.2% increase in children’s HOMA-IR (P-value = 0.002. This study shows that children’s adiposity and maternal IR are positively associated with children’s IR.

  16. Regulation of Multidrug Resistance Proteins by Genistein in a Hepatocarcinoma Cell Line: Impact on Sorafenib Cytotoxicity

    OpenAIRE

    2015-01-01

    Hepatocellular carcinoma (HCC) is the fifth most frequent cancer worldwide. Sorafenib is the only drug available that improves the overall survival of HCC patients. P-glycoprotein (P-gp), Multidrug resistance-associated proteins 2 and 3 (MRP2 and 3) and Breast cancer resistance protein (BCRP) are efflux pumps that play a key role in cancer chemoresistance. Their modulation by dietary compounds may affect the intracellular accumulation and therapeutic efficacy of drugs that are substrates of t...

  17. High-resolution structure of the antibiotic resistance protein NimA from Deinococcus radiodurans.

    Science.gov (United States)

    Leiros, Hanna Kirsti S; Tedesco, Consiglia; McSweeney, Seán M

    2008-06-01

    Many anaerobic human pathogenic bacteria are treated using 5-nitroimidazole-based (5-Ni) antibiotics, a class of inactive prodrugs that contain a nitro group. The nitro group must be activated in an anaerobic one-electron reduction and is therefore dependent on the redox system in the target cells. Antibiotic resistance towards 5-Ni drugs is found to be related to the nim genes (nimA, nimB, nimC, nimD, nimE and nimF), which are proposed to encode a reductase that is responsible for converting the nitro group of the antibiotic into a nonbactericidal amine. A mechanism for the Nim enzyme has been proposed in which two-electron reduction of the nitro group leads to the generation of nontoxic derivatives and confers resistance against these antibiotics. The cofactor was found to be important in the mechanism and was found to be covalently linked to the reactive His71. In this paper, the 1.2 A atomic resolution crystal structure of the 5-nitroimidazole antibiotic resistance protein NimA from Deinococcus radiodurans (DrNimA) is presented. A planar cofactor is clearly visible and well defined in the electron-density map adjacent to His71, the identification of the cofactor and its properties are discussed.

  18. Folate concentration dependent transport activity of the Multidrug Resistance Protein 1 (ABCC1).

    NARCIS (Netherlands)

    Hooijberg, J.H.; Jansen, G.; Assaraf, Y.G.; Kathmann, I.; Pieters, R.; Laan, AC; Veerman, A.J.P.; Kaspers, G.J.L.; Peters, G.J.

    2004-01-01

    The Multidrug Resistance Protein MRP1 (ABCC1) can confer resistance to a variety of therapeutic drugs. In addition, MRP1/ABCC1 mediates cellular export of natural folates, such as folic acid and l-leucovorin. In this study we determined whether cellular folate status affected the functional activity

  19. Identification of a putative protein-profile associating with tamoxifen therapy-resistance in breast cancer

    NARCIS (Netherlands)

    A. Umar (Arzu); J.W.M. Martens (John); J.A. Foekens (John); L. Paša-Tolić (Ljiljana); H. Kang; A.M. Timmermans (Mieke); M.P. Look (Maxime); M.E. Meijer van Gelder (Marion); N. Jaitly (Navdeep); M.A. den Bakker (Michael)

    2009-01-01

    textabstractTamoxifen-resistance is a major cause of death in patients with recurrent breast cancer. Current clinical parameters can correctly predict therapy response in only half of the treated patients. Identification of proteins that associate with tamoxifen-resistance is a first step towards

  20. Differentially expressed proteins in human breast cancer cells sensitive and resistant to paclitaxel.

    Science.gov (United States)

    Pavlikova, Nela; Bartonova, Irena; Dincakova, Lucia; Halada, Petr; Kovar, Jan

    2014-08-01

    The resistance of cancer cells to chemotherapeutic drugs represents a major problem in cancer treatment. Despite all efforts, mechanisms of resistance have not yet been elucidated. To reveal proteins that could be involved in resistance to taxanes, we compared protein expression in whole cell lysates of SK-BR-3 breast cancer cells sensitive to paclitaxel and in lysates of the same line with acquired resistance to paclitaxel. The resistant SK-BR-3 cell line was established in our lab. Protein separation was achieved using high-resolution 2D-electrophoresis, computer analysis and mass spectro-metry. With these techniques we identified four proteins with different expression in resistant SK-BR-3 cells, i.e., serpin B3, serpin B4, heat shock protein 27 (all three upregulated) and cytokeratin 18 (downregulated). Observed changes were confirmed using western blot analysis. This study suggests new directions worthy of further study in the effort to reveal the mechanism of resistance to paclitaxel in breast cancer cells.

  1. Topological robustness analysis of protein interaction networks reveals key targets for overcoming chemotherapy resistance in glioma

    Science.gov (United States)

    Azevedo, Hátylas; Moreira-Filho, Carlos Alberto

    2015-11-01

    Biological networks display high robustness against random failures but are vulnerable to targeted attacks on central nodes. Thus, network topology analysis represents a powerful tool for investigating network susceptibility against targeted node removal. Here, we built protein interaction networks associated with chemoresistance to temozolomide, an alkylating agent used in glioma therapy, and analyzed their modular structure and robustness against intentional attack. These networks showed functional modules related to DNA repair, immunity, apoptosis, cell stress, proliferation and migration. Subsequently, network vulnerability was assessed by means of centrality-based attacks based on the removal of node fractions in descending orders of degree, betweenness, or the product of degree and betweenness. This analysis revealed that removing nodes with high degree and high betweenness was more effective in altering networks’ robustness parameters, suggesting that their corresponding proteins may be particularly relevant to target temozolomide resistance. In silico data was used for validation and confirmed that central nodes are more relevant for altering proliferation rates in temozolomide-resistant glioma cell lines and for predicting survival in glioma patients. Altogether, these results demonstrate how the analysis of network vulnerability to topological attack facilitates target prioritization for overcoming cancer chemoresistance.

  2. Leaf Treatments with a Protein-Based Resistance Inducer Partially Modify Phyllosphere Microbial Communities of Grapevine

    Science.gov (United States)

    Cappelletti, Martina; Perazzolli, Michele; Antonielli, Livio; Nesler, Andrea; Torboli, Esmeralda; Bianchedi, Pier L.; Pindo, Massimo; Puopolo, Gerardo; Pertot, Ilaria

    2016-01-01

    Protein derivatives and carbohydrates can stimulate plant growth, increase stress tolerance, and activate plant defense mechanisms. However, these molecules can also act as a nutritional substrate for microbial communities living on the plant phyllosphere and possibly affect their biocontrol activity against pathogens. We investigated the mechanisms of action of a protein derivative (nutrient broth, NB) against grapevine downy mildew, specifically focusing on the effects of foliar treatments on plant defense stimulation and on the composition and biocontrol features of the phyllosphere microbial populations. NB reduced downy mildew symptoms and induced the expression of defense-related genes in greenhouse- and in vitro-grown plants, indicating the activation of grapevine resistance mechanisms. Furthermore, NB increased the number of culturable phyllosphere bacteria and altered the composition of bacterial and fungal populations on leaves of greenhouse-grown plants. Although, NB-induced changes on microbial populations were affected by the structure of indigenous communities originally residing on grapevine leaves, degrees of disease reduction and defense gene modulation were consistent among the experiments. Thus, modifications in the structure of phyllosphere populations caused by NB application could partially contribute to downy mildew control by competition for space or other biocontrol strategies. Particularly, changes in the abundance of phyllosphere microorganisms may provide a contribution to resistance induction, partially affecting the hormone-mediated signaling pathways involved. Modifying phyllosphere populations by increasing natural biocontrol agents with the application of selected nutritional factors can open new opportunities in terms of sustainable plant protection strategies. PMID:27486468

  3. Leaf Treatments with a Protein-Based Resistance Inducer Partially Modify Phyllosphere Microbial Communities of Grapevine.

    Science.gov (United States)

    Cappelletti, Martina; Perazzolli, Michele; Antonielli, Livio; Nesler, Andrea; Torboli, Esmeralda; Bianchedi, Pier L; Pindo, Massimo; Puopolo, Gerardo; Pertot, Ilaria

    2016-01-01

    Protein derivatives and carbohydrates can stimulate plant growth, increase stress tolerance, and activate plant defense mechanisms. However, these molecules can also act as a nutritional substrate for microbial communities living on the plant phyllosphere and possibly affect their biocontrol activity against pathogens. We investigated the mechanisms of action of a protein derivative (nutrient broth, NB) against grapevine downy mildew, specifically focusing on the effects of foliar treatments on plant defense stimulation and on the composition and biocontrol features of the phyllosphere microbial populations. NB reduced downy mildew symptoms and induced the expression of defense-related genes in greenhouse- and in vitro-grown plants, indicating the activation of grapevine resistance mechanisms. Furthermore, NB increased the number of culturable phyllosphere bacteria and altered the composition of bacterial and fungal populations on leaves of greenhouse-grown plants. Although, NB-induced changes on microbial populations were affected by the structure of indigenous communities originally residing on grapevine leaves, degrees of disease reduction and defense gene modulation were consistent among the experiments. Thus, modifications in the structure of phyllosphere populations caused by NB application could partially contribute to downy mildew control by competition for space or other biocontrol strategies. Particularly, changes in the abundance of phyllosphere microorganisms may provide a contribution to resistance induction, partially affecting the hormone-mediated signaling pathways involved. Modifying phyllosphere populations by increasing natural biocontrol agents with the application of selected nutritional factors can open new opportunities in terms of sustainable plant protection strategies.

  4. Leaf treatments with a protein-based resistance inducer partially modify phyllosphere microbial communities of grapevine

    Directory of Open Access Journals (Sweden)

    Martina Cappelletti

    2016-07-01

    Full Text Available Protein derivatives and carbohydrates can stimulate plant growth, increase stress tolerance and activate plant defense mechanisms. However, these molecules can also act as a nutritional substrate for microbial communities living on the plant phyllosphere and possibly affect their biocontrol activity against pathogens. We investigated the mechanisms of action of a protein derivative (nutrient broth, NB against grapevine downy mildew, specifically focusing on the effects of foliar treatments on plant defense stimulation and on the composition and biocontrol features of the phyllosphere microbial populations. NB reduced downy mildew symptoms and induced the expression of defense-related genes in greenhouse- and in vitro-grown plants, indicating the activation of grapevine resistance mechanisms. Furthermore, NB increased the number of culturable phyllosphere bacteria and altered the composition of bacterial and fungal populations on leaves of greenhouse-grown plants. Although NB-induced changes on microbial populations were affected by the structure of indigenous communities originally residing on grapevine leaves, degrees of disease reduction and defense gene modulation were consistent among the experiments. Thus, modifications in the structure of phyllosphere populations caused by NB application could partially contribute to downy mildew control by competition for space or other biocontrol strategies. Particularly, changes in the abundance of phyllosphere microorganisms may provide a contribution to resistance induction, partially affecting the hormone-mediated signaling pathways involved. Modifying phyllosphere populations by increasing natural biocontrol agents with the application of selected nutritional factors can open new opportunities in terms of sustainable plant protection strategies.

  5. Relative resistance of Pacific salmon to infectious salmon anaemia virus

    Science.gov (United States)

    Rolland, J.B.; Winton, J.R.

    2003-01-01

    Infectious salmon anaemia (ISA) is a major disease of Atlantic salmon, Salmo salar, caused by an orthomyxovirus (ISAV). Increases in global aqua culture and the international movement of fish made it important to determine if Pacific salmon are at risk. Steelhead trout, Oncorhynchus mykiss, and chum, O. keta, Chinook, O. tshawytscha, coho, O. kisutch, and Atlantic salmon were injected intraperitoneally with a high, medium, or low dose of a Norwegian strain of ISAV. In a second challenge, the same species, except chum salmon, were injected with a high dose of either a Canadian or the Norwegian strain. Average cumulative mortality of Atlantic salmon in trial 1 was 12% in the high dose group, 20% in the medium dose group and 16% in the low dose group. The average cumulative mortality of Atlantic salmon in trial 2 was 98%. No signs typical of ISA and no ISAV-related mortality occurred among any of the groups of Oncorhynchus spp. in either experiment, although ISAV was reisolated from some fish sampled at intervals post-challenge. The results indicate that while Oncorhynchus spp. are quite resistant to ISAV relative to Atlantic salmon, the potential for ISAV to adapt to Oncorhynchus spp. should not be ignored.

  6. Pronounced energy restriction with elevated protein intake results in no change in proteolysis and reductions in skeletal muscle protein synthesis that are mitigated by resistance exercise.

    Science.gov (United States)

    Hector, Amy J; McGlory, Chris; Damas, Felipe; Mazara, Nicole; Baker, Steven K; Phillips, Stuart M

    2017-09-12

    Preservation of lean body mass (LBM) may be important during dietary energy restriction (ER) and requires equal rates of muscle protein synthesis (MPS) and muscle protein breakdown (MPB). Currently, the relative contribution of MPS and MPB to the loss of LBM during ER in humans is unknown. We aimed to determine the impact of dietary protein intake and resistance exercise on MPS and MPB during a controlled short-term energy deficit. Adult men (body mass index, 28.6 ± 0.6 kg/m(2); age 22 ± 1 yr) underwent 10 d of 40%-reduced energy intake while performing unilateral resistance exercise and consuming lower protein (1.2 g/kg/d, n = 12) or higher protein (2.4 g/kg per d, n = 12). Pre- and postintervention testing included dual-energy X-ray absorptiometry, primed constant infusion of ring-[(13)C6]phenylalanine, and (15)[N]phenylalanine to measure acute postabsorptive MPS and MPB; D2O to measure integrated MPS; and gene and protein expression. There was a decrease in acute MPS after ER (higher protein, 0.059 ± 0.006 to 0.051 ± 0.009%/h; lower protein, 0.061 ± 0.005-0.045 ± 0.006%/h; P resistance exercise (higher protein, 0.067 ± 0.01%/h; lower protein, 0.061 ± 0.006%/h), and integrated MPS followed a similar pattern. There was no change in MPB (energy balance, 0.080 ± 0.01%/hr; ER rested legs, 0.078 ± 0.008%/hr; ER exercised legs, 0.079 ± 0.006%/hr). We conclude that a reduction in MPS is the main mechanism that underpins LBM loss early in ER in adult men.-Hector, A. J., McGlory, C., Damas, F., Mazara, N., Baker, S. K., Phillips, S. M. Pronounced energy restriction with elevated protein intake results in no change in proteolysis and reductions in skeletal muscle protein synthesis that are mitigated by resistance exercise. © FASEB.

  7. Transport proteins determine drug sensitivity and resistance in a protozoan parasite, Trypanosoma brucei

    Science.gov (United States)

    Munday, Jane C.; Settimo, Luca; de Koning, Harry P.

    2015-01-01

    Drug resistance in pathogenic protozoa is very often caused by changes to the ‘transportome’ of the parasites. In Trypanosoma brucei, several transporters have been implicated in uptake of the main classes of drugs, diamidines and melaminophenyl arsenicals. The resistance mechanism had been thought to be due to loss of a transporter known to carry both types of agents: the aminopurine transporter P2, encoded by the gene TbAT1. However, although loss of P2 activity is well-documented as the cause of resistance to the veterinary diamidine diminazene aceturate (DA; Berenil®), cross-resistance between the human-use arsenical melarsoprol and the diamidine pentamidine (melarsoprol/pentamidine cross resistance, MPXR) is the result of loss of a separate high affinity pentamidine transporter (HAPT1). A genome-wide RNAi library screen for resistance to pentamidine, published in 2012, gave the key to the genetic identity of HAPT1 by linking the phenomenon to a locus that contains the closely related T. brucei aquaglyceroporin genes TbAQP2 and TbAQP3. Further analysis determined that knockdown of only one pore, TbAQP2, produced the MPXR phenotype. TbAQP2 is an unconventional aquaglyceroporin with unique residues in the “selectivity region” of the pore, and it was found that in several MPXR lab strains the WT gene was either absent or replaced by a chimeric protein, recombined with parts of TbAQP3. Importantly, wild-type AQP2 was also absent in field isolates of T. b. gambiense, correlating with the outcome of melarsoprol treatment. Expression of a wild-type copy of TbAQP2 in even the most resistant strain completely reversed MPXR and re-introduced HAPT1 function and transport kinetics. Expression of TbAQP2 in Leishmania mexicana introduced a pentamidine transport activity indistinguishable from HAPT1. Although TbAQP2 has been shown to function as a classical aquaglyceroporin it is now clear that it is also a high affinity drug transporter, HAPT1. We discuss here a

  8. Acupuncture Alters Expression of Insulin Signaling Related Molecules and Improves Insulin Resistance in OLETF Rats

    Directory of Open Access Journals (Sweden)

    Xin-Yu Huang

    2016-01-01

    Full Text Available To determine effect of acupuncture on insulin resistance in Otsuka Long-Evans Tokushima Fatty (OLETF rats and to evaluate expression of insulin signaling components. Rats were divided into three groups: Sprague-Dawley (SD rats, OLETF rats, and acupuncture+OLETF rats. Acupuncture was subcutaneously applied to Neiguan (PC6, Zusanli (ST36, and Sanyinjiao (SP6; in contrast, acupuncture to Shenshu (BL23 was administered perpendicularly. For Neiguan (PC6 and Zusanli (ST36, needles were connected to an electroacupuncture (EA apparatus. Fasting blood glucose (FPG was measured by glucose oxidase method. Plasma fasting insulin (FINS and serum C peptide (C-P were determined by ELISA. Protein and mRNA expressions of insulin signaling molecules were determined by Western blot and real-time RT-PCR, respectively. OLETF rats exhibit increased levels of FPG, FINS, C-P, and homeostasis model assessment-estimated insulin resistance (HOMA-IR, which were effectively decreased by acupuncture treatment. mRNA expressions of several insulin signaling related molecules IRS1, IRS2, Akt2, aPKCζ, and GLUT4 were decreased in OLETF rats compared to SD controls. Expression of these molecules was restored back to normal levels upon acupuncture administration. PI3K-p85α was increased in OLETF rats; this increase was also reversed by acupuncture treatment. Acupuncture improves insulin resistance in OLETF rats, possibly via regulating expression of key insulin signaling related molecules.

  9. Novel Vip3-Related Protein from Bacillus thuringiensis†

    OpenAIRE

    Rang, Cécile; Gil, Patricia; Neisner, Nathalie; Van Rie, Jeroen; Frutos, Roger

    2005-01-01

    A novel vip3-related gene was identified in Bacillus thuringiensis. This novel gene is 2,406 bp long and codes for a 91-kDa protein (801 amino acids). This novel protein exhibits between 61 and 62% similarity with Vip3A proteins and is designated Vip3Ba1. Vip3Ba1 has several specific features. Differences between Vip3Ba1 and the Vip3A proteins are spread throughout the sequence but are more frequent in the C-terminal part from amino acid 456 onward. The regions containing the two proteolytic ...

  10. Trehalose glycopolymer resists allow direct writing of protein patterns by electron-beam lithography

    Science.gov (United States)

    Bat, Erhan; Lee, Juneyoung; Lau, Uland Y.; Maynard, Heather D.

    2015-03-01

    Direct-write patterning of multiple proteins on surfaces is of tremendous interest for a myriad of applications. Precise arrangement of different proteins at increasingly smaller dimensions is a fundamental challenge to apply the materials in tissue engineering, diagnostics, proteomics and biosensors. Herein, we present a new resist that protects proteins during electron-beam exposure and its application in direct-write patterning of multiple proteins. Polymers with pendant trehalose units are shown to effectively crosslink to surfaces as negative resists, while at the same time providing stabilization to proteins during the vacuum and electron-beam irradiation steps. In this manner, arbitrary patterns of several different classes of proteins such as enzymes, growth factors and immunoglobulins are realized. Utilizing the high-precision alignment capability of electron-beam lithography, surfaces with complex patterns of multiple proteins are successfully generated at the micrometre and nanometre scale without requiring cleanroom conditions.

  11. Study on Drug Resistance and Relative Mechanisms of Chlamydia Trachomatis

    Institute of Scientific and Technical Information of China (English)

    侯淑萍; 刘全忠

    2004-01-01

    Abstract: Chlamydia Trachomatis (C.T.) is one of the most common pathogens of human sexually transmitted diseases. Treatment of C.T. infection primarily depends on Tetracyclines, Macrolides and Quinolones, but with the wide use of antibiotics an increasing number of drug-resistant Chlamydia trachomatis cases have been reported. This review summarizes the resistant conditions and the possible resistance mechanisms of C.T..

  12. Prediction of disease-related mutations affecting protein localization

    Directory of Open Access Journals (Sweden)

    Laurila Kirsti

    2009-03-01

    Full Text Available Abstract Background Eukaryotic cells contain numerous compartments, which have different protein constituents. Proteins are typically directed to compartments by short peptide sequences that act as targeting signals. Translocation to the proper compartment allows a protein to form the necessary interactions with its partners and take part in biological networks such as signalling and metabolic pathways. If a protein is not transported to the correct intracellular compartment either the reaction performed or information carried by the protein does not reach the proper site, causing either inactivation of central reactions or misregulation of signalling cascades, or the mislocalized active protein has harmful effects by acting in the wrong place. Results Numerous methods have been developed to predict protein subcellular localization with quite high accuracy. We applied bioinformatics methods to investigate the effects of known disease-related mutations on protein targeting and localization by analyzing over 22,000 missense mutations in more than 1,500 proteins with two complementary prediction approaches. Several hundred putative localization affecting mutations were identified and investigated statistically. Conclusion Although alterations to localization signals are rare, these effects should be taken into account when analyzing the consequences of disease-related mutations.

  13. Heat shock protein 27, a novel regulator of 5-fluorouracil resistance in colon cancer.

    Science.gov (United States)

    Tsuruta, Masashi; Nishibori, Hideki; Hasegawa, Hirotoshi; Ishii, Yoshiyuki; Endo, Takashi; Kubota, Tetsuro; Kitajima, Masaki; Kitagawa, Yuko

    2008-11-01

    The resistance of colon cancer to 5-fluorouracil (5-FU) is a critical issue, and the cause of this resistance cannot always be explained based on the known molecules. Heat shock protein 27 (HSP27) mRNA expression has recently been shown to be correlated with 5-FU resistance in 5-FU-resistant cell lines. In this study, we attempted to elucidate the functional mechanism of HSP27 in 5-FU resistance in colon cancer. HSP27 protein levels in several human colon cancer cell lines (LoVo, HCT15, WiDr, HCT116, HT-29 and SW480) were determined by immunoblot and densitometry analysis. The in vitro growth inhibition rates (IR) of the cell lines at various concentrations of 5-FU were assessed by MTT assay. The degree of 5-FU resistance was estimated as the drug concentration inducing 50% IR (IC50). The HSP27 protein level and IC50 were significantly correlated in these cell lines (p=0.010). The effect of HSP27 overexpression on IC50 was evaluated in LoVo cells. HSP27 transfectants significantly increased IC50 and reduced HSP27 resistance. The effect of HSP27 down-regulation by HSP27 siRNA on IC50 was confirmed in HCT15 cells. HSP27 siRNA suppressed HSP27 protein levels and reduced IC50 in a dose-dependent manner. These data indicated that HSP27 is closely connected with 5-FU resistance in colon cancer and suggested that HSP27 levels predicted 5-FU resistance. HSP27 down-regulation overcame 5-FU resistance and HSP27 may be a clinical target in patients with 5-FU-resistant colon cancer.

  14. Differential expression of salivary proteins between susceptible and insecticide-resistant mosquitoes of Culex quinquefasciatus.

    Directory of Open Access Journals (Sweden)

    Innocent Djegbe

    Full Text Available BACKGROUND: The Culex quinquefasciatus mosquito, a major pest and vector of filariasis and arboviruses in the tropics, has developed multiple resistance mechanisms to the main insecticide classes currently available in public health. Among them, the insensitive acetylcholinesterase (ace-1(R allele is widespread worldwide and confers cross-resistance to organophosphates and carbamates. Fortunately, in an insecticide-free environment, this mutation is associated with a severe genetic cost that can affect various life history traits. Salivary proteins are directly involved in human-vector contact during biting and therefore play a key role in pathogen transmission. METHODS AND RESULTS: An original proteomic approach combining 2D-electrophoresis and mass spectrometry was adopted to compare the salivary expression profiles of two strains of C. quinquefasciatus with the same genetic background but carrying either the ace-1(R resistance allele or not (wild type. Four salivary proteins were differentially expressed (>2 fold, P<0.05 in susceptible (SLAB and resistant (SR mosquito strains. Protein identification indicated that the D7 long form, a major salivary protein involved in blood feeding success, presented lower expression in the resistant strain than the susceptible strain. In contrast, three other proteins, including metabolic enzymes (endoplasmin, triosephosphate isomerase were significantly over-expressed in the salivary gland of ace-1(R resistant mosquitoes. A catalogue of 67 salivary proteins of C. quinquefasciatus sialotranscriptome was also identified and described. CONCLUSION: The "resistance"-dependent expression of salivary proteins in mosquitoes may have considerable impact on biting behaviour and hence on the capacity to transmit parasites/viruses to humans. The behaviour of susceptible and insecticide-resistant mosquitoes in the presence of vertebrate hosts and its impact on pathogen transmission urgently requires further

  15. High dietary protein intake, reducing or eliciting insulin resistance?

    NARCIS (Netherlands)

    Rietman, A.; Schwarz, J.; Tome, D.; Kok, F.J.; Mensink, M.R.

    2014-01-01

    Dietary proteins have an insulinotropic effect and thus promote insulin secretion, which indeed leads to enhanced glucose clearance from the blood. In the long term, however, a high dietary protein intake is associated with an increased risk of type 2 diabetes. Moreover, branched-chain amino acids (

  16. High dietary protein intake, reducing or eliciting insulin resistance?

    NARCIS (Netherlands)

    Rietman, A.; Schwarz, J.; Tome, D.; Kok, F.J.; Mensink, M.R.

    2014-01-01

    Dietary proteins have an insulinotropic effect and thus promote insulin secretion, which indeed leads to enhanced glucose clearance from the blood. In the long term, however, a high dietary protein intake is associated with an increased risk of type 2 diabetes. Moreover, branched-chain amino acids

  17. Crystal structure of the TLDc domain of oxidation resistance protein 2 from zebrafish

    DEFF Research Database (Denmark)

    Blaise, Mickael; Alsarraf, Husam Mohammad Ali Baker; Wong, Jaslyn

    2012-01-01

    The oxidation resistance proteins (OXR) help to protect eukaryotes from reactive oxygen species. The sole C-terminal domain of the OXR, named TLDc is sufficient to perform this function. However, the mechanism by which oxidation resistance occurs is poorly understood. We present here the crystal...... structure of the TLDc domain of the oxidation resistance protein 2 from zebrafish. The structure was determined by X-ray crystallography to atomic resolution (0.97Å) and adopts an overall globular shape. Two antiparallel β-sheets form a central β-sandwich, surrounded by two helices and two one-turn helices...

  18. Novel Genes Related to Ceftriaxone Resistance Found among Ceftriaxone-Resistant Neisseria gonorrhoeae Strains Selected In Vitro.

    Science.gov (United States)

    Gong, Zijian; Lai, Wei; Liu, Min; Hua, Zhengshuang; Sun, Yayin; Xu, Qingfang; Xia, Yue; Zhao, Yue; Xie, Xiaoyuan

    2016-04-01

    The emergence of ceftriaxone-resistantNeisseria gonorrhoeaeis currently a global public health concern. However, the mechanism of ceftriaxone resistance is not yet fully understood. To investigate the potential genes related to ceftriaxone resistance inNeisseria gonorrhoeae, we subcultured six gonococcal strains with increasing concentrations of ceftriaxone and isolated the strains that became resistant. After analyzing several frequently reported genes involved in ceftriaxone resistance, we found only a single mutation inpenA(A501V). However, differential analysis of the genomes and transcriptomes between pre- and postselection strains revealed many other mutated genes as well as up- and downregulated genes. Transformation of the mutatedpenAgene into nonresistant strains increased the MIC between 2.0- and 5.3-fold, and transformation of mutatedftsXincreased the MIC between 3.3- and 13.3-fold. Genes encoding the ABC transporters FarB, Tfq, Hfq, and ExbB were overexpressed, whilepilM,pilN, andpilQwere downregulated. Furthermore, the resistant strain developed cross-resistance to penicillin and cefuroxime, had an increased biochemical metabolic rate, and presented fitness defects such as prolonged growth time and downregulated PilMNQ. In conclusion, antimicrobial pressure could result in the emergence of ceftriaxone resistance, and the evolution of resistance ofNeisseria gonorrhoeaeto ceftriaxone is a complicated process at both the pretranscriptional and posttranscriptional levels, involving several resistance mechanisms of increased efflux and decreased entry.

  19. Oxidative modification of proteins: age-related changes.

    Science.gov (United States)

    Chakravarti, Bulbul; Chakravarti, Deb N

    2007-01-01

    Aging is a complex biological phenomenon which involves progressive loss of different physiological functions of various tissues of living organisms. It is the inevitable fate of life and is a major risk factor for death and different pathological disorders. Based on a wide variety of studies performed in humans as well as in various animal models and microbial systems, reactive oxygen species (ROS) are believed to play a key role in the aging process. The production of ROS is influenced by cellular metabolic activities as well as environmental factors. ROS can react with all major biological macromolecules such as carbohydrates, nucleic acids, lipids, and proteins. Since, in general, proteins are the key molecules that play the ultimate role in various structural and functional aspects of living organisms, this review will focus on the age-related oxidative modifications of proteins as well as on mechanism for removal or repair of the oxidized proteins. The topics covered include protein oxidation as a marker of oxidative stress, experimental evidence indicating the role of ROS in protein oxidation, protein carbonyl content, enzymatic degradation of oxidized proteins, and effects of caloric restriction on protein oxidation in the context of aging. Finally, we will discuss different strategies which have been or can be undertaken to slow down the oxidative damage of proteins and the aging process.

  20. Analyzing pepsin degradation assay conditions used for allergenicity assessments to ensure that pepsin susceptible and pepsin resistant dietary proteins are distinguishable

    Science.gov (United States)

    Edrington, Thomas C.; Storrs, S. Bradley; Crowley, Kathleen S.; Ward, Jason M.; Lee, Thomas C.; Liu, Zi L.; Li, Bin; Glenn, Kevin C.

    2017-01-01

    The susceptibility of a dietary protein to proteolytic degradation by digestive enzymes, such as gastric pepsin, provides information on the likelihood of systemic exposure to a structurally intact and biologically active macromolecule, thus informing on the safety of proteins for human and animal consumption. Therefore, the purpose of standardized in vitro degradation studies that are performed during protein safety assessments is to distinguish whether proteins of interest are susceptible or resistant to pepsin degradation via a study design that enables study-to-study comparison. Attempting to assess pepsin degradation under a wide-range of possible physiological conditions poses a problem because of the lack of robust and consistent data collected under a large-range of sub-optimal conditions, which undermines the needs to harmonize in vitro degradation conditions. This report systematically compares the effects of pH, incubation time, and pepsin-to-substrate protein ratio on the relative degradation of five dietary proteins: three pepsin susceptible proteins [ribulose 1,5-bisphosphate carboxylase-oxygenase (Rubisco), horseradish peroxidase (HRP), hemoglobin (Hb)], and two pepsin resistant proteins [lipid transfer protein (LTP) and soybean trypsin inhibitor (STI)]. The results indicate that proteins susceptible to pepsin degradation are readily distinguishable from pepsin-resistant proteins when the reaction conditions are within the well-characterized optima for pepsin. The current standardized in vitro pepsin resistant assay with low pH and high pepsin-to-substrate ratio fits this purpose. Using non-optimal pH and/or pepsin-to-substrate protein ratios resulted in susceptible proteins no longer being reliably degraded by this stomach enzyme, which compromises the ability of this in vitro assay to distinguish between resistant and susceptible proteins and, therefore, no longer providing useful data to an overall weight-of-evidence approach to assessing safety

  1. Breast cancer resistance protein (BCRP/ABCG2): its role in multidrug resistance and regulation of its gene expression

    Institute of Scientific and Technical Information of China (English)

    Takeo Nakanishi; Douglas D. Ross

    2012-01-01

    Breast cancer resistance protein (BCRP)/ATP-binding cassette subfamily G member 2 (ABCG2) is an ATP-binding cassette (ABC) transporter identified as a molecular cause of multidrug resistance (MDR) in diverse cancer cells.BCRP physiologically functions as a part of a self-defense mechanism for the organism; it enhances elimination of toxic xenobiotic substances and harmful agents in the gut and biliary tract,as well as through the blood-brain,placental,and possibly blood-testis barriers.BCRP recognizes and transports numerous anticancer drugs including conventional chemotherapeutic and targeted small therapeutic molecules relatively new in clinical use.Thus,BCRP expression in cancer cells directly causes MDR by active efflux of anticancer drugs.Because BCRP is also known to be a stem cell marker,its expression in cancer cells could be a manifestation of metabolic and signaling pathways that confer multiple mechanisms of drug resistance,self-renewal (stemness),and invasiveness (aggressiveness),and thereby impart a poor prognosis.Therefore,blocking BCRP-mediated active efflux may provide a therapeutic benefit for cancers.Delineating the precise molecular mechanisms for BCRP gene expression may lead to identification of a novel molecular target to modulate BCRP-mediated MDR.Current evidence suggests that BCRP gene transcription is regulated by a number of trans-acting elements including hypoxia inducible factor 1α, estrogen receptor, and peroxisome proliferator-activated receptor.Furthermore,alternative promoter usage,demethylation of the BCRP promoter,and histone modificationare likely associated with drug-induced BCRP overexpression in cancer cells.Finally,PI3K/AKT signaling may play a critical role in modulating BCRP function under a variety of conditions.These biological events seem involved in a complicated manner.Untangling the events would be an essential first step to developing a method to modulate BCRP function to aid patients with cancer.This review will

  2. Dynamic changes and surveillance function of prion protein expression in gastric cancer drug resistance

    Institute of Scientific and Technical Information of China (English)

    Ji-Heng Wang; Jing-Ping Du; Ying-Hai Zhang; Xiao-Jun Zhao; Ru-Ying Fan; Zhi-Hong Wang; Zi-Tao Wu; Ying Han

    2011-01-01

    AIM: To explore the dynamic changes of prion protein (PrPc) in the process of gastric cancer drug resistance and the role of PrPc expression in the prognosis of gastric cancer patients receiving chemotherapy. METHODS: A series of gastric cancer cell lines resistant to different concentrations of adriamycin was established,and the expression of PrPc, Bcl-2 and Bax was detected in these cells. Apoptosis was determined using Annexin V staining. Western blotting and immunohistochemistry were performed to detect the expression of PrPc in patients receiving chemotherapy and to explore the role of PrPc expression in predicting the chemosensitivity and the outcome of gastric cancer patients receiving chemotherapy. Follow-up was performed for 2 years. RESULTS: PrPc expression was increased with the increase in drug resistance. Bcl-2, together with PrPc, increased the level of anti-apoptosis of cancer cells. Increased PrPc expression predicted the enhanced level of anti-apoptosis and resistance to anticancer drugs. PrPc expression could be used as a marker for predicting the efficacy of chemotherapy and the prognosis of gastric cancer. Increased PrPc expression predicted both poor chemosensitivity and a low 2-year survival rate. Contrarily, low PrPc expression predicted favorable chemosensitivity and a relatively high 2-year survival rate.CONCLUSION: PrPc expression is associated with histological types and differentiation of gastric cancer cells; The PrPc expression level might be a valuable marker in predicting the efficacy of chemotherapy and the prognosis of gastric cancer patients receiving chemotherapy.

  3. Discovery of genes related to insecticide resistance in Bactrocera dorsalis by functional genomic analysis of a de novo assembled transcriptome.

    Directory of Open Access Journals (Sweden)

    Ju-Chun Hsu

    Full Text Available Insecticide resistance has recently become a critical concern for control of many insect pest species. Genome sequencing and global quantization of gene expression through analysis of the transcriptome can provide useful information relevant to this challenging problem. The oriental fruit fly, Bactrocera dorsalis, is one of the world's most destructive agricultural pests, and recently it has been used as a target for studies of genetic mechanisms related to insecticide resistance. However, prior to this study, the molecular data available for this species was largely limited to genes identified through homology. To provide a broader pool of gene sequences of potential interest with regard to insecticide resistance, this study uses whole transcriptome analysis developed through de novo assembly of short reads generated by next-generation sequencing (NGS. The transcriptome of B. dorsalis was initially constructed using Illumina's Solexa sequencing technology. Qualified reads were assembled into contigs and potential splicing variants (isotigs. A total of 29,067 isotigs have putative homologues in the non-redundant (nr protein database from NCBI, and 11,073 of these correspond to distinct D. melanogaster proteins in the RefSeq database. Approximately 5,546 isotigs contain coding sequences that are at least 80% complete and appear to represent B. dorsalis genes. We observed a strong correlation between the completeness of the assembled sequences and the expression intensity of the transcripts. The assembled sequences were also used to identify large numbers of genes potentially belonging to families related to insecticide resistance. A total of 90 P450-, 42 GST-and 37 COE-related genes, representing three major enzyme families involved in insecticide metabolism and resistance, were identified. In addition, 36 isotigs were discovered to contain target site sequences related to four classes of resistance genes. Identified sequence motifs were also

  4. Discovery of Genes Related to Insecticide Resistance in Bactrocera dorsalis by Functional Genomic Analysis of a De Novo Assembled Transcriptome

    Science.gov (United States)

    Hsu, Ju-Chun; Wu, Wen-Jer; Feng, Hai-Tung; Haymer, David S.; Chen, Chien-Yu

    2012-01-01

    Insecticide resistance has recently become a critical concern for control of many insect pest species. Genome sequencing and global quantization of gene expression through analysis of the transcriptome can provide useful information relevant to this challenging problem. The oriental fruit fly, Bactrocera dorsalis, is one of the world's most destructive agricultural pests, and recently it has been used as a target for studies of genetic mechanisms related to insecticide resistance. However, prior to this study, the molecular data available for this species was largely limited to genes identified through homology. To provide a broader pool of gene sequences of potential interest with regard to insecticide resistance, this study uses whole transcriptome analysis developed through de novo assembly of short reads generated by next-generation sequencing (NGS). The transcriptome of B. dorsalis was initially constructed using Illumina's Solexa sequencing technology. Qualified reads were assembled into contigs and potential splicing variants (isotigs). A total of 29,067 isotigs have putative homologues in the non-redundant (nr) protein database from NCBI, and 11,073 of these correspond to distinct D. melanogaster proteins in the RefSeq database. Approximately 5,546 isotigs contain coding sequences that are at least 80% complete and appear to represent B. dorsalis genes. We observed a strong correlation between the completeness of the assembled sequences and the expression intensity of the transcripts. The assembled sequences were also used to identify large numbers of genes potentially belonging to families related to insecticide resistance. A total of 90 P450-, 42 GST-and 37 COE-related genes, representing three major enzyme families involved in insecticide metabolism and resistance, were identified. In addition, 36 isotigs were discovered to contain target site sequences related to four classes of resistance genes. Identified sequence motifs were also analyzed to

  5. Endothelin and calciotropic hormones share regulatory pathways in multidrug resistance protein 2-mediated transport

    NARCIS (Netherlands)

    Wever, K.E.; Masereeuw, R.; Miller, D.S.; Hang, X.M.; Flik, G.

    2006-01-01

    The kidney of vertebrates plays a key role in excretion of endogenous waste products and xenobiotics. Active secretion in the proximal nephron is at the basis of this excretion, mediated by carrier proteins including multidrug resistance protein 2 (Mrp2). We previously showed that Mrp2 function is

  6. Identifying the Proteins that Mediate the Ionizing Radiation Resistance of Deinococcus Radiodurans R1

    Energy Technology Data Exchange (ETDEWEB)

    Battista, John R

    2010-02-22

    The primary objectives of this proposal was to define the subset of proteins required for the ionizing radiation (IR) resistance of Deinococcus radiodurans R1, characterize the activities of those proteins, and apply what was learned to problems of interest to the Department of Energy.

  7. Protein Structure Is Related to RNA Structural Reactivity In Vivo.

    Science.gov (United States)

    Tang, Yin; Assmann, Sarah M; Bevilacqua, Philip C

    2016-02-27

    We assessed whether in vivo mRNA structural reactivity and the structure of the encoded protein are related. This is the first investigation of such a relationship that utilizes information on RNA structure obtained in living cells. Based on our recent genome-wide Structure-seq analysis in Arabidopsis thaliana, we report that, as a meta property, regions of individual mRNAs that code for protein domains generally have higher reactivity to DMS (dimethyl sulfate), a chemical that covalently modifies accessible As and Cs, than regions that encode protein domain junctions. This relationship is prominent for proteins annotated for catalytic activity and reversed in proteins annotated for binding and transcription regulatory activity. Upon analyzing intrinsically disordered proteins, we found a similar pattern for disordered regions as compared to ordered regions: regions of individual mRNAs that code for ordered regions have significantly higher DMS reactivity than regions that code for intrinsically disordered regions. Based on these effects, we hypothesize that the decreased DMS reactivity of RNA regions that encode protein domain junctions or intrinsically disordered regions may reflect increased RNA structure that may slow translation, allowing time for the nascent protein domain or ordered region of the protein to fold, thereby reducing protein misfolding. In addition, a drop in DMS reactivity was observed on portions of mRNA sequences that correspond to the C-termini of protein domains, suggesting ribosome protection at these mRNA regions. Structural relationships between mRNAs and their encoded proteins may have evolved to allow efficient and accurate protein folding.

  8. cuticleDB: a relational database of Arthropod cuticular proteins

    Directory of Open Access Journals (Sweden)

    Willis Judith H

    2004-09-01

    Full Text Available Abstract Background The insect exoskeleton or cuticle is a bi-partite composite of proteins and chitin that provides protective, skeletal and structural functions. Little information is available about the molecular structure of this important complex that exhibits a helicoidal architecture. Scores of sequences of cuticular proteins have been obtained from direct protein sequencing, from cDNAs, and from genomic analyses. Most of these cuticular protein sequences contain motifs found only in arthropod proteins. Description cuticleDB is a relational database containing all structural proteins of Arthropod cuticle identified to date. Many come from direct sequencing of proteins isolated from cuticle and from sequences from cDNAs that share common features with these authentic cuticular proteins. It also includes proteins from the Drosophila melanogaster and the Anopheles gambiae genomes, that have been predicted to be cuticular proteins, based on a Pfam motif (PF00379 responsible for chitin binding in Arthropod cuticle. The total number of the database entries is 445: 370 derive from insects, 60 from Crustacea and 15 from Chelicerata. The database can be accessed from our web server at http://bioinformatics.biol.uoa.gr/cuticleDB. Conclusions CuticleDB was primarily designed to contain correct and full annotation of cuticular protein data. The database will be of help to future genome annotators. Users will be able to test hypotheses for the existence of known and also of yet unknown motifs in cuticular proteins. An analysis of motifs may contribute to understanding how proteins contribute to the physical properties of cuticle as well as to the precise nature of their interaction with chitin.

  9. Protein expression analysis of inflammation-related colon carcinogenesis

    Directory of Open Access Journals (Sweden)

    Yasui Yumiko

    2009-01-01

    Full Text Available Background: Chronic inflammation is a risk factor for colorectal cancer (CRC development. The aim of this study was to determine the differences in protein expression between CRC and the surrounding nontumorous colonic tissues in the mice that received azoxymethane (AOM and dextran sodium sulfate (DSS using a proteomic analysis. Materials and Methods: Male ICR mice were given a single intraperitoneal injection of AOM (10 mg/kg body weight, followed by 2% (w/v DSS in their drinking water for seven days, starting one week after the AOM injection. Colonic adenocarcinoma developed after 20 weeks and a proteomics analysis based on two-dimensional gel electrophoresis and ultraflex TOF/TOF mass spectrometry was conducted in the cancerous and nontumorous tissue specimens. Results: The proteomic analysis revealed 21 differentially expressed proteins in the cancerous tissues in comparison to the nontumorous tissues. There were five markedly increased proteins (beta-tropomyosin, tropomyosin 1 alpha isoform b, S100 calcium binding protein A9, and an unknown protein and 16 markedly decreased proteins (Car1 proteins, selenium-binding protein 1, HMG-CoA synthase, thioredoxin 1, 1 Cys peroxiredoxin protein 2, Fcgbp protein, Cytochrome c oxidase, subunit Va, ETHE1 protein, and 7 unknown proteins. Conclusions: There were 21 differentially expressed proteins in the cancerous tissues of the mice that received AOM and DSS. Their functions include metabolism, the antioxidant system, oxidative stress, mucin production, and inflammation. These findings may provide new insights into the mechanisms of inflammation-related colon carcinogenesis and the establishment of novel therapies and preventative strategies to treat carcinogenesis in the inflamed colon.

  10. Brain protein oxidation in age-related neurodegenerative disorders that are associated with aggregated proteins.

    Science.gov (United States)

    Butterfield, D A; Kanski, J

    2001-07-15

    Protein oxidation, one of a number of brain biomarkers of oxidative stress, is increased in several age-related neurodegenerative disorders or animal models thereof, including Alzheimer's disease, Huntington's disease, prion disorders, such as Creutzfeld-Jakob disease, and alpha-synuclein disorders, such as Parkinson's disease and frontotemporal dementia. Each of these neurodegenerative disorders is associated with aggregated proteins in brain. However, the relationship among protein oxidation, protein aggregation, and neurodegeneration remain unclear. The current rapid progress in elucidation of mechanisms of protein oxidation in neuronal loss should provide further insight into the importance of free radical oxidative stress in these neurodegenerative disorders.

  11. Enhanced disease resistance and drought tolerance in transgenic rice plants overexpressing protein elicitors from Magnaporthe oryzae.

    Science.gov (United States)

    Wang, Zhenzhen; Han, Qiang; Zi, Qian; Lv, Shun; Qiu, Dewen; Zeng, Hongmei

    2017-01-01

    Exogenous application of the protein elicitors MoHrip1 and MoHrip2, which were isolated from the pathogenic fungus Magnaporthe oryzae (M. oryzae), was previously shown to induce a hypersensitive response in tobacco and to enhance resistance to rice blast. In this work, we successfully transformed rice with the mohrip1 and mohrip2 genes separately. The MoHrip1 and MoHrip2 transgenic rice plants displayed higher resistance to rice blast and stronger tolerance to drought stress than wild-type (WT) rice and the vector-control pCXUN rice. The expression of salicylic acid (SA)- and abscisic acid (ABA)-related genes was also increased, suggesting that these two elicitors may trigger SA signaling to protect the rice from damage during pathogen infection and regulate the ABA content to increase drought tolerance in transgenic rice. Trypan blue staining indicated that expressing MoHrip1 and MoHrip2 in rice plants inhibited hyphal growth of the rice blast fungus. Relative water content (RWC), water usage efficiency (WUE) and water loss rate (WLR) were measured to confirm the high capacity for water retention in transgenic rice. The MoHrip1 and MoHrip2 transgenic rice also exhibited enhanced agronomic traits such as increased plant height and tiller number.

  12. Bodipy-FL-Verapamil: A Fluorescent Probe for the Study of Multidrug Resistance Proteins

    Directory of Open Access Journals (Sweden)

    Anna Rosati

    2004-01-01

    Full Text Available Most of the substances used as fluorescent probes to study drug transport and the effect of efflux blockers in multidrug resistant cells have many drawbacks, such as toxicity, unspecific background, accumulation in mitochondria. New fluorescent compounds, among which Bodipy‐FL‐verapamil (BV, have been therefore proposed as more useful tools. The uptake of BV has been evaluated by cytofluorimetry and fluorescence microscopy using cell lines that overexpress P‐glycoprotein (P388/ADR and LLC‐PK1/ADR or MRP (multidrug resistance‐related protein (PANC‐1 and clinical specimens from patients. The effect of specific inhibitors for P‐glycoprotein (verapamil and vinblastine or MRP (MK571 and probenecid has been also studied. BV intracellular concentrations were significantly lower in the two P‐glycoprotein overexpressing cell lines in comparison with the parental lines. In addition, verapamil and vinblastine increased the intracellular concentrations of the dye; MK571 and probenecid, two MRP inhibitors, increased BV levels in PANC‐1 cells, that express this protein. These findings were confirmed in clinical specimens from patients. Fluorescence microscopy revealed a faint fluorescence emission in P‐glycoprotein or MRP expressing cell lines; however, treatment with specific inhibitors significantly increased the fluorescence. BV is a useful tool for studying multidrug resistance proteins with different techniques such as cytofluorimetry and fluorescence microscopy, but does not discriminate between P‐glycoprotein and MRP. In comparison with other classic fluorescent probes, the assay with this dye is extremely rapid, simple, not toxic for cells, devoid of fluorescent background, and can be useful in the clinical settings.

  13. Identification of Functional Regulatory Residues of the β-Lactam Inducible Penicillin Binding Protein in Methicillin-Resistant Staphylococcus aureus

    OpenAIRE

    Mbah, Andreas N.; Isokpehi, Raphael D

    2013-01-01

    Resistance to methicillin by Staphylococcus aureus is a persistent clinical problem worldwide. A mechanism for resistance has been proposed in which methicillin resistant Staphylococcus aureus (MRSA) isolates acquired a new protein called β -lactam inducible penicillin binding protein (PBP-2′). The PBP-2′ functions by substituting other penicillin binding proteins which have been inhibited by β -lactam antibiotics. Presently, there is no structural and regulatory information on PBP-2′ protein...

  14. Tardigrade workbench: comparing stress-related proteins, sequence-similar and functional protein clusters as well as RNA elements in tardigrades

    OpenAIRE

    Frohme Marcus; Schnölzer Martina; Engelmann Julia C; Beisser Daniela; Shkumatov Alexander; Liang Chuanguang; Förster Frank; Müller Tobias; Schill Ralph O; Dandekar Thomas

    2009-01-01

    Abstract Background Tardigrades represent an animal phylum with extraordinary resistance to environmental stress. Results To gain insights into their stress-specific adaptation potential, major clusters of related and similar proteins are identified, as well as specific functional clusters delineated comparing all tardigrades and individual species (Milnesium tardigradum, Hypsibius dujardini, Echiniscus testudo, Tulinus stephaniae, Richtersius coronifer) and functional elements in tardigrade ...

  15. Tardigrade workbench: comparing stress-related proteins, sequence-similar and functional protein clusters as well as RNA elements in tardigrades

    OpenAIRE

    Frohme Marcus; Schnölzer Martina; Engelmann Julia C; Beisser Daniela; Shkumatov Alexander; Liang Chuanguang; Förster Frank; Müller Tobias; Schill Ralph O; Dandekar Thomas

    2009-01-01

    Abstract Background Tardigrades represent an animal phylum with extraordinary resistance to environmental stress. Results To gain insights into their stress-specific adaptation potential, major clusters of related and similar proteins are identified, as well as specific functional clusters delineated comparing all tardigrades and individual species (Milnesium tardigradum, Hypsibius dujardini, Echiniscus testudo, Tulinus stephaniae, Richtersius coronifer) and functional elements in tardigrade ...

  16. A protein relational database and protein family knowledge bases to facilitate structure-based design analyses.

    Science.gov (United States)

    Mobilio, Dominick; Walker, Gary; Brooijmans, Natasja; Nilakantan, Ramaswamy; Denny, R Aldrin; Dejoannis, Jason; Feyfant, Eric; Kowticwar, Rupesh K; Mankala, Jyoti; Palli, Satish; Punyamantula, Sairam; Tatipally, Maneesh; John, Reji K; Humblet, Christine

    2010-08-01

    The Protein Data Bank is the most comprehensive source of experimental macromolecular structures. It can, however, be difficult at times to locate relevant structures with the Protein Data Bank search interface. This is particularly true when searching for complexes containing specific interactions between protein and ligand atoms. Moreover, searching within a family of proteins can be tedious. For example, one cannot search for some conserved residue as residue numbers vary across structures. We describe herein three databases, Protein Relational Database, Kinase Knowledge Base, and Matrix Metalloproteinase Knowledge Base, containing protein structures from the Protein Data Bank. In Protein Relational Database, atom-atom distances between protein and ligand have been precalculated allowing for millisecond retrieval based on atom identity and distance constraints. Ring centroids, centroid-centroid and centroid-atom distances and angles have also been included permitting queries for pi-stacking interactions and other structural motifs involving rings. Other geometric features can be searched through the inclusion of residue pair and triplet distances. In Kinase Knowledge Base and Matrix Metalloproteinase Knowledge Base, the catalytic domains have been aligned into common residue numbering schemes. Thus, by searching across Protein Relational Database and Kinase Knowledge Base, one can easily retrieve structures wherein, for example, a ligand of interest is making contact with the gatekeeper residue.

  17. Reverse-phase protein microarrays (RPPA) as a diagnostic and therapeutic guide in multidrug resistant leukemia.

    Science.gov (United States)

    Maraldi, Tullia; Bertacchini, Jessika; Benincasa, Marta; Guida, Marianna; De Pol, Anto; Liotta, Lance A; Petricoin, Emanuel; Cocco, Lucio; Marmiroli, Sandra

    2011-02-01

    Reverse-phase microarray assays using phospho-specific antibodies (RPPA) can directly measure levels of phosphorylated protein isoforms. In the current study, lysates from parental and multidrug resistant (MDR) CEM leukemia cells were spotted onto reverse-phase protein microarrays and probed with a panel of phospho-antibodies to ERK, PCK and Akt pathways. In particular, the Akt pathway is considered to play significant roles in leukemia and Akt inhibitor therapy has been proposed as a potential tool in the treatment of this disease. The RPPA data prompted us to investigate deeper this pathway. Here, we found that whereas total Akt1 protein level is higher in parental CEM cells, the activated isoform content, p-Akt1, increases in doxorubicin-selected CEM cells (MDR-CEM). This was backed up by Western blot analysis, confirming that Akt1 activity/phosphorylation may be up-regulated in MDR-CEM cells. Further exploration of inhibitory therapy in this system was evaluated. The TNF-related apoptosis-inducing ligand, TRAIL, has been shown to selectively kill tumor cells. Herein, we describe that in MDR-CEM cells TRAIL responsiveness correlates with a reduced expression of endogenous Akt1, suggesting that the MDR phenotype associated to P-gp sensitizes cells to TRAIL therapy.

  18. Transport proteins determine drug sensitivity and resistance in a protozoan parasite, Trypanosoma brucei

    Directory of Open Access Journals (Sweden)

    Jane Claire Munday

    2015-03-01

    Full Text Available Drug resistance in pathogenic protozoa is very often caused by changes to the ‘transportome’ of the parasites. In Trypanosoma brucei, several transporters have been implicated in uptake of the main classes of drugs, diamidines and melaminophenyl arsenicals. The resistance mechanism had been thought to be due to loss of a transporter known to carry both types of agents: the aminopurine transporter P2, encoded by the gene TbAT1. However, although loss of P2 activity is well-documented as the cause of resistance to the veterinary diamidine diminazene aceturate (Berenil®, cross-resistance between the human-use arsenical melarsoprol and the diamidine pentamidine (MPXR is the result of loss of a separate High Affinity Pentamidine Transporter (HAPT1. A genome-wide RNAi library screen for resistance to pentamidine, published in 2012, gave the key to the genetic identity of HAPT1 by linking the phenomenon to a locus that contains the closely related T. brucei aquaglyceroporin genes TbAQP2 and TbAQP3. Further analysis determined that knockdown of only one pore, TbAQP2, produced the MPXR phenotype. TbAQP2 is an unconventional aquaglyceroporin with unique residues in the selectivity region of the pore, and it was found that in several MPXR lab strains the WT gene was either absent or replaced by a chimeric protein, recombined with parts of TbAQP3. Importantly, wild-type AQP2 was also absent in field isolates of T. b. gambiense, correlating with the outcome of melarsoprol treatment. Expression of a wild-type copy of TbAQP2 in even the most resistant strain completely reversed MPXR and re-introduced HAPT1 function and transport kinetics. Expression of TbAQP2 in Leishmania mexicana introduced a pentamidine transport activity indistinguishable from HAPT1. Although TbAQP2 has been shown to function as a classical aquaglyceroporin it is now clear that it is also a high affinity drug transporter, HAPT1. We discuss here a possible structural rationale for this

  19. Differential expression of salivary proteins between susceptible and insecticide-resistant mosquitoes of Culex quinquefasciatus.

    Science.gov (United States)

    Djegbe, Innocent; Cornelie, Sylvie; Rossignol, Marie; Demettre, Edith; Seveno, Martial; Remoue, Franck; Corbel, Vincent

    2011-03-23

    The Culex quinquefasciatus mosquito, a major pest and vector of filariasis and arboviruses in the tropics, has developed multiple resistance mechanisms to the main insecticide classes currently available in public health. Among them, the insensitive acetylcholinesterase (ace-1(R) allele) is widespread worldwide and confers cross-resistance to organophosphates and carbamates. Fortunately, in an insecticide-free environment, this mutation is associated with a severe genetic cost that can affect various life history traits. Salivary proteins are directly involved in human-vector contact during biting and therefore play a key role in pathogen transmission. An original proteomic approach combining 2D-electrophoresis and mass spectrometry was adopted to compare the salivary expression profiles of two strains of C. quinquefasciatus with the same genetic background but carrying either the ace-1(R) resistance allele or not (wild type). Four salivary proteins were differentially expressed (>2 fold, Pmosquito strains. Protein identification indicated that the D7 long form, a major salivary protein involved in blood feeding success, presented lower expression in the resistant strain than the susceptible strain. In contrast, three other proteins, including metabolic enzymes (endoplasmin, triosephosphate isomerase) were significantly over-expressed in the salivary gland of ace-1(R) resistant mosquitoes. A catalogue of 67 salivary proteins of C. quinquefasciatus sialotranscriptome was also identified and described. The "resistance"-dependent expression of salivary proteins in mosquitoes may have considerable impact on biting behaviour and hence on the capacity to transmit parasites/viruses to humans. The behaviour of susceptible and insecticide-resistant mosquitoes in the presence of vertebrate hosts and its impact on pathogen transmission urgently requires further investigation. All proteomic data will be deposited at PRIDE (http://www.ebi.ac.uk/pride/).

  20. Relative quantification of several plasma proteins during liver transplantation surgery.

    Science.gov (United States)

    Parviainen, Ville; Joenväärä, Sakari; Tukiainen, Eija; Ilmakunnas, Minna; Isoniemi, Helena; Renkonen, Risto

    2011-01-01

    Plasma proteome is widely used in studying changes occurring in human body during disease or other disturbances. Immunological methods are commonly used in such studies. In recent years, mass spectrometry has gained popularity in high-throughput analysis of plasma proteins. In this study, we tested whether mass spectrometry and iTRAQ-based protein quantification might be used in proteomic analysis of human plasma during liver transplantation surgery to characterize changes in protein abundances occurring during early graft reperfusion. We sampled blood from systemic circulation as well as blood entering and exiting the liver. After immunodepletion of six high-abundant plasma proteins, trypsin digestion, iTRAQ labeling, and cation-exchange fractionation, the peptides were analyzed by reverse phase nano-LC-MS/MS. In total, 72 proteins were identified of which 31 could be quantified in all patient specimens collected. Of these 31 proteins, ten, mostly medium-to-high abundance plasma proteins with a concentration range of 50-2000 mg/L, displayed relative abundance change of more than 10%. The changes in protein abundance observed in this study allow further research on the role of several proteins in ischemia-reperfusion injury during liver transplantation and possibly in other surgery.

  1. Relative Quantification of Several Plasma Proteins during Liver Transplantation Surgery

    Directory of Open Access Journals (Sweden)

    Ville Parviainen

    2011-01-01

    Full Text Available Plasma proteome is widely used in studying changes occurring in human body during disease or other disturbances. Immunological methods are commonly used in such studies. In recent years, mass spectrometry has gained popularity in high-throughput analysis of plasma proteins. In this study, we tested whether mass spectrometry and iTRAQ-based protein quantification might be used in proteomic analysis of human plasma during liver transplantation surgery to characterize changes in protein abundances occurring during early graft reperfusion. We sampled blood from systemic circulation as well as blood entering and exiting the liver. After immunodepletion of six high-abundant plasma proteins, trypsin digestion, iTRAQ labeling, and cation-exchange fractionation, the peptides were analyzed by reverse phase nano-LC-MS/MS. In total, 72 proteins were identified of which 31 could be quantified in all patient specimens collected. Of these 31 proteins, ten, mostly medium-to-high abundance plasma proteins with a concentration range of 50–2000 mg/L, displayed relative abundance change of more than 10%. The changes in protein abundance observed in this study allow further research on the role of several proteins in ischemia-reperfusion injury during liver transplantation and possibly in other surgery.

  2. An improved algorithm for activated protein C resistance and factor V Leiden screening.

    Science.gov (United States)

    Herskovits, Adrianna Z; Morgan, Elizabeth A; Lemire, Susan J; Lindeman, Neal I; Dorfman, David M

    2013-09-01

    To evaluate the performance of a Russell viper venom-based activated protein C resistance (APCR) screening test relative to DNA analysis for the factor V Leiden mutation. We evaluated the concordance between Pefakit APCR screening results and DNA analysis for 435 patients homozygous (n = 11), heterozygous (n = 310), or wild-type (n =114) for the G1691A allele. Using receiver operating characteristic analysis, we found that a cutoff of 1.89 for the APCR ratio yields a sensitivity and specificity of 99.1%. In patients with discrepant genotype-phenotype correlation, their APCR may provide a more clinically relevant result. We compared several strategies for employing reflex testing and found that performing initial APCR screening followed by confirmatory molecular analysis on a subset of cases in the borderline regions between the diagnostic groups can reduce unnecessary testing by approximately 80% without compromising diagnostic accuracy.

  3. Dietary proteins and food-related reward signals

    Directory of Open Access Journals (Sweden)

    Katri Peuhkuri

    2011-06-01

    Full Text Available Proteins play a crucial role in almost all biological processes. Dietary proteins are generally considered as energy yielding nutrients and as a source of amino acids for various purposes. In addition, they may have a role in food-related reward signals. The purpose of this review was to give an overview of the role of dietary proteins in food-related reward and possible mechanisms behind such effects. Dietary proteins may elicit food-related reward by several different postprandial mechanisms, including neural and humoral signals from the gastrointestinal tract to the brain. In order to exert rewarding effects, protein have to be absorbed from the intestine and reach the target cells in sufficient concentrations, or act via receptors ad cell signalling in the gut without absorption. Complex interactions between different possible mechanisms make it very difficult to gain a clear view on the role and intesity of each mechanism. It is concluded that, in principle, dietary proteins may have a role in food-related reward. However, the evidence is based mostly on experiments with animal models and one should be careful in drawing conclusions of clinical relevance.

  4. Two-dimensional Electrophoresis Analysis of Proteins in Response to Cold Stress in Extremely Cold-resistant Winter Wheat Dongnongdongmai 1 Tillering Nodes

    Institute of Scientific and Technical Information of China (English)

    Cang Jing; Yu Jing; Liu Li-jie; Yang Yang; Cui Hong; Hao Zai-bin; Li Zhuo-fu

    2012-01-01

    The overwintering survival ratio of the cultivar Dongnongdongmai 1 with strong cold-resistance in paramos of Heilongjiang Province in China are over 85%. The tillering nodes are the most important organs for overwintering survival of winter wheat, because there are more substances associated with cold resistance in tillering nodes than those in leaves and roots. Proteins in the tillering nodes of the cold-resistant cultivar Dongnongdongmai 1 grown under field conditions with or without any lowtemperature stress were analyzed by 2-dimensional electrophoresis and identified by mass spectrometry. In the range of pH 4-7, the expression of 37 proteins showed obvious difference (±more than two fold) in the proteomic maps of cold-stressed and non-stressed tillering nodes, including a new protein spot. All proteins exhibiting the difference in expression were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, followed by a database search for protein identification and function prediction. Five groups of proteins were confirmed, namely stress-related proteins (22%), metabolism-associated proteins (35%), and signaling molecules (24%), cell wall-binding proteins (5%), unclear proteins (14%). This indicated that tillering node cells supported the energy requirements of plant growth and stress resistance by signal transduction adapting to metabolism and structure.

  5. Biophysical characterization and mutational analysis of the antibiotic resistance protein NimA from Deinococcus radiodurans.

    Science.gov (United States)

    Leiros, Hanna-Kirsti S; Brandsdal, Bjørn Olav; McSweeney, Seán M

    2010-04-01

    Metronidazole (MTZ) is an antibiotic commonly used to treat anaerobic bacterial infections in humans and animals. Antibiotic resistance toward this class of 5-nitroimidazole (5-Ni) drug derivatives has been related to the Nim genes thought to encode a reductase. Here we report the biophysical characteristics of the NimA protein from Deinococcus radiodurans (DrNimA) binding to MTZ and three other 5-Ni drugs. The interaction energies of the protein and antibiotic are studied by isothermal titration calorimetry (ITC) and with free energy and linear interaction energy (LIE) calculations, where the latter method revealed that the antibiotic binding is mainly of hydrophobic character. ITC measurements further found that one DrNimA dimer has two antibiotic binding sites which were not affected by mutation of the reactive His71. The observed association constants (K(a)) were in the range of 5.1-4910(4)M(-1) and the enthalpy release upon binding to DrNimA for the four drugs studied was relatively low (approximately -1 kJ/mol) but still measurable. The drug binding is mainly entropy driven and along with the hydrophobic drug binding site found by crystallography, this possibly explains the low observed enthalpy values. The effect of the His71 mutation and the presence of MTZ were studied by differential scanning calorimetry (DSC). Native DrNimA is a yellow colored protein where the interaction from His71 to the cofactor is thought to be responsible for the coloring. Mutations of His71 to Ala, Ser, Leu or Asp all gave transparent, colorless protein solutions, and the two mutant crystal structures of DrNimA-H71A and DrNimA-H71S presented revealed no cofactor binding.

  6. Proteomic Comparison between Maturation Drying and Prematurely Imposed Drying of Zea mays Seeds Reveals a Potential Role of Maturation Drying in Preparing Proteins for Seed Germination, Seedling Vigor, and Pathogen Resistance

    DEFF Research Database (Denmark)

    Wang, Wei-Qing; Ye, Jian-Qing; Rogowska-Wrzesinska, Adelina

    2014-01-01

    abundant in this group and may contribute to the acquisition of seed germinability. However, a relatively large number of proteins changed in the embryo (47 spots) and endosperm (76 spots) specifically during maturation drying. Among these proteins, storage proteins in the embryo and defense proteins...... in the endosperm may be particularly important for seedling vigor and resistance to fungal infection, respectively....

  7. Partly replacing meat protein with soy protein alters insulin resistance and blood lipids in postmenopausal women with abdominal obesity

    NARCIS (Netherlands)

    Nielen, van M.; Feskens, E.J.M.; Rietman, A.; Siebelink, E.; Mensink, M.R.

    2014-01-01

    Increasing protein intake and soy consumption appear to be promising approaches to prevent metabolic syndrome (MetS). However, the effect of soy consumption on insulin resistance, glucose homeostasis, and other characteristics of MetS is not frequently studied in humans. We aimed to investigate the

  8. Differential display of vincristine-resistance-related genes in gastric cancer SGC7901 cells

    Institute of Scientific and Technical Information of China (English)

    Xin Wang; Bo-Rong Pan; Jian-Ping Jin; Dai-Ming Fan; Mei Lan; Yong-Quan Shi; Ju Lu; Yue-Xia Zhong; Han-Ping Wu; Hui-Hong Zai; Jie Ding; Kai-Cun Wu

    2002-01-01

    AIM: To isolate and clone the vincristine-resistine-relatedgenes in gastric cancer SGC7901 cell line and to clarify themultidrug-resistant molecular mechanism of gastric cancercells.METHODS: The modified differential-display polymerasechain reaction (DD-PCR) was used to examine thedifferences in the mRNA composition of Vincristine-resistantgastric cancer SGC 7901 cells (SGC7901/VCR), induced byvincristine sulfate versus SGC7901cells. The differentiallyexpressed cDNA fragments were confirmed byreverseNorthern analysis, sequencing, BLAST analysis andNorthern bolt analysis.RESULTS: DD-PCR identified that 54 cDNA fragments werepreferentially expressed in SGC 7901/VCR cells. When thesecDNA fragments were analyzed by reverseNorthern blot, 20were reproducibly expressed at a high level in SGC7901/VCR. Sequencing and BLAST analysis revealed that sevenof the genes were known genes: ADP-ribosylation factor 4,cytochrorne oxidase subunit Ⅱ, Ss-A/Ro ribonucleoprteinautoantigen 60kd subunit, ribosomal protein S13, galaectin-8 gene, oligophrenin 1 mRNA, and ribosomal protein L23mRNA; and thirteen of the genes were unknown genes. Thelength and abundance of the four unknown genes mRNAwere further confirmed by Northern blot analysis.CONCLUSION: The twenty differential known and unknowngenes may be related to the vincristine-resistant mechanismin human gastric cancer SGC7901 cell line.

  9. Structural studies of human glioma pathogenesis-related protein 1

    Energy Technology Data Exchange (ETDEWEB)

    Asojo, Oluwatoyin A., E-mail: oasojo@unmc.edu [College of Medicine, Nebraska Medical Center, Omaha, NE 68198-6495 (United States); Koski, Raymond A.; Bonafé, Nathalie [L2 Diagnostics LLC, 300 George Street, New Haven, CT 06511 (United States); College of Medicine, Nebraska Medical Center, Omaha, NE 68198-6495 (United States)

    2011-10-01

    Structural analysis of a truncated soluble domain of human glioma pathogenesis-related protein 1, a membrane protein implicated in the proliferation of aggressive brain cancer, is presented. Human glioma pathogenesis-related protein 1 (GLIPR1) is a membrane protein that is highly upregulated in brain cancers but is barely detectable in normal brain tissue. GLIPR1 is composed of a signal peptide that directs its secretion, a conserved cysteine-rich CAP (cysteine-rich secretory proteins, antigen 5 and pathogenesis-related 1 proteins) domain and a transmembrane domain. GLIPR1 is currently being investigated as a candidate for prostate cancer gene therapy and for glioblastoma targeted therapy. Crystal structures of a truncated soluble domain of the human GLIPR1 protein (sGLIPR1) solved by molecular replacement using a truncated polyalanine search model of the CAP domain of stecrisp, a snake-venom cysteine-rich secretory protein (CRISP), are presented. The correct molecular-replacement solution could only be obtained by removing all loops from the search model. The native structure was refined to 1.85 Å resolution and that of a Zn{sup 2+} complex was refined to 2.2 Å resolution. The latter structure revealed that the putative binding cavity coordinates Zn{sup 2+} similarly to snake-venom CRISPs, which are involved in Zn{sup 2+}-dependent mechanisms of inflammatory modulation. Both sGLIPR1 structures have extensive flexible loop/turn regions and unique charge distributions that were not observed in any of the previously reported CAP protein structures. A model is also proposed for the structure of full-length membrane-bound GLIPR1.

  10. Hinge Atlas: relating protein sequence to sites of structural flexibility

    OpenAIRE

    Yang Julie; Lu Long J; Flores Samuel C; Carriero Nicholas; Gerstein Mark B

    2007-01-01

    Abstract Background Relating features of protein sequences to structural hinges is important for identifying domain boundaries, understanding structure-function relationships, and designing flexibility into proteins. Efforts in this field have been hampered by the lack of a proper dataset for studying characteristics of hinges. Results Using the Molecular Motions Database we have created a Hinge Atlas of manually annotated hinges and a statistical formalism for calculating the enrichment of v...

  11. Unsignaled delay of reinforcement, relative time, and resistance to change.

    Science.gov (United States)

    Shahan, Timothy A; Lattal, Kennon A

    2005-05-01

    Two experiments with pigeons examined the effects of unsignaled, nonresetting delays of reinforcement on responding maintained by different reinforcement rates. In Experiment 1, 3-s unsignaled delays were introduced into each component of a multiple variable-interval (VI) 15-s VI 90-s VI 540-s schedule. When considered as a proportion of the preceding immediate reinforcement baseline, responding was decreased similarly for the three multiple-schedule components in both the first six and last six sessions of exposure to the delay. In addition, the relation between response rates and reinforcement rates was altered such that both parameters of the single-response version of the matching law (i.e., k and Re) were decreased. Experiment 2 examined the effects of unsignaled delays ranging from 0.5 s to 8.0 s on responding maintained by a multiple VI 20-s VI 120-s schedule of reinforcement. Response rates in both components increased with brief unsignaled delays and decreased with longer delays. As in Experiment 1, response rates as a proportion of baseline were affected similarly for the two components in both the first six and last six sessions of exposure to the delay. Unlike delays imposed between two stimulus events, the effects of delays between responses and reinforcers do not appear to be attenuated when the average time between reinforcers is longer. In addition, the disruptions produced by unsignaled delays appear to be inconsistent with the general finding that responding maintained by higher rates of reinforcement is less resistant to change.

  12. The Plasmin-Sensitive Protein Pls in Methicillin-Resistant Staphylococcus aureus (MRSA) Is a Glycoprotein

    Science.gov (United States)

    Pohlentz, Gottfried; Xia, Guoqing; Hussain, Muzaffar; Foster, Simon; Peters, Georg

    2017-01-01

    Most bacterial glycoproteins identified to date are virulence factors of pathogenic bacteria, i.e. adhesins and invasins. However, the impact of protein glycosylation on the major human pathogen Staphylococcus aureus remains incompletely understood. To study protein glycosylation in staphylococci, we analyzed lysostaphin lysates of methicillin-resistant Staphylococcus aureus (MRSA) strains by SDS-PAGE and subsequent periodic acid-Schiff’s staining. We detected four (>300, ∼250, ∼165, and ∼120 kDa) and two (>300 and ∼175 kDa) glycosylated surface proteins with strain COL and strain 1061, respectively. The ∼250, ∼165, and ∼175 kDa proteins were identified as plasmin-sensitive protein (Pls) by mass spectrometry. Previously, Pls has been demonstrated to be a virulence factor in a mouse septic arthritis model. The pls gene is encoded by the staphylococcal cassette chromosome (SCC)mec type I in MRSA that also encodes the methicillin resistance-conferring mecA and further genes. In a search for glycosyltransferases, we identified two open reading frames encoded downstream of pls on the SCCmec element, which we termed gtfC and gtfD. Expression and deletion analysis revealed that both gtfC and gtfD mediate glycosylation of Pls. Additionally, the recently reported glycosyltransferases SdgA and SdgB are involved in Pls glycosylation. Glycosylation occurs at serine residues in the Pls SD-repeat region and modifying carbohydrates are N-acetylhexosaminyl residues. Functional characterization revealed that Pls can confer increased biofilm formation, which seems to involve two distinct mechanisms. The first mechanism depends on glycosylation of the SD-repeat region by GtfC/GtfD and probably also involves eDNA, while the second seems to be independent of glycosylation as well as eDNA and may involve the centrally located G5 domains. Other previously known Pls properties are not related to the sugar modifications. In conclusion, Pls is a glycoprotein and Pls glycosyl

  13. Protein-flavour interactions in relation to development of novel protein foods

    NARCIS (Netherlands)

    Heng, L.; Koningsveld, van G.A.; Gruppen, H.; Boekel, van M.A.J.S.; Vincken, J.P.; Roozen, J.P.; Voragen, A.G.J.

    2004-01-01

    Proteins are known to interact with relatively small molecules such as flavour compounds and saponins, and may thus influence the taste perception of food. In this study, the interactions of flavour volatiles with pea proteins, and the effects of heat on these interactions were investigated. The pre

  14. Haptoglobin-related protein is a high-affinity hemoglobin-binding plasma protein

    DEFF Research Database (Denmark)

    Nielsen, Marianne Jensby; Petersen, Steen Vang; Jacobsen, Christian

    2006-01-01

    Haptoglobin-related protein (Hpr) is a primate-specific plasma protein associated with apolipoprotein L-I (apoL-I)-containing high-density lipoprotein (HDL) particles shown to be a part of the innate immune defense. Despite the assumption hitherto that Hpr does not bind to hemoglobin, the present...

  15. MRP proteins as potential mediators of heavy metal resistance in zebrafish cells.

    Science.gov (United States)

    Long, Yong; Li, Qing; Wang, Youhui; Cui, Zongbin

    2011-04-01

    Acquired resistance of mammalian cells to heavy metals is closely relevant to enhanced expression of several multidrug resistance-associated proteins (MRP), but it remains unclear whether MRP proteins confer resistance to heavy metals in zebrafish. In this study, we obtained zebrafish (Danio rerio) fibroblast-like ZF4 cells with resistance to toxic heavy metals after chronic cadmium exposure and selection for 6months. These cadmium-resistant cells (ZF4-Cd) were maintained in 5μM cadmium and displayed cross-resistance to cadmium, mercury, arsenite and arsenate. ZF4-Cd cells remained the resistance to heavy metals after protracted culture in cadmium-free medium. In comparison with ZF4-WT cells, ZF4-Cd cells exhibited accelerated rate of cadmium excretion, enhanced activity of MRP-like transport, elevated expression of abcc2, abcc4 and mt2 genes, and increased content of cellular GSH. Inhibition of MRP-like transport activity, GSH biosynthesis and GST activity significantly attenuated the resistance of ZF4-Cd cells to heavy metals. The results indicate that some of MRP transporters are involved in the efflux of heavy metals conjugated with cellular GSH and thus play crucial roles in heavy metal detoxification of zebrafish cells.

  16. Complement factor H-related proteins CFHR2 and CFHR5 represent novel ligands for the infection-associated CRASP proteins of Borrelia burgdorferi.

    Directory of Open Access Journals (Sweden)

    Corinna Siegel

    Full Text Available BACKGROUND: One virulence property of Borrelia burgdorferi is its resistance to innate immunity, in particular to complement-mediated killing. Serum-resistant B. burgdorferi express up to five distinct complement regulator-acquiring surface proteins (CRASP which interact with complement regulator factor H (CFH and factor H-like protein 1 (FHL1 or factor H-related protein 1 (CFHR1. In the present study we elucidate the role of the infection-associated CRASP-3 and CRASP-5 protein to serve as ligands for additional complement regulatory proteins as well as for complement resistance of B. burgdorferi. METHODOLOGY/PRINCIPAL FINDINGS: To elucidate whether CRASP-5 and CRASP-3 interact with various human proteins, both borrelial proteins were immobilized on magnetic beads. Following incubation with human serum, bound proteins were eluted and separated by Glycine-SDS-PAGE. In addition to CFH and CFHR1, complement regulators CFHR2 and CFHR5 were identified as novel ligands for both borrelial proteins by employing MALDI-TOF. To further assess the contributions of CRASP-3 and CRASP-5 to complement resistance, a serum-sensitive B. garinii strain G1 which lacks all CFH-binding proteins was used as a valuable model for functional analyses. Both CRASPs expressed on the B. garinii outer surface bound CFH as well as CFHR1 and CFHR2 in ELISA. In contrast, live B. garinii bound CFHR1, CFHR2, and CFHR5 and only miniscute amounts of CFH as demonstrated by serum adsorption assays and FACS analyses. Further functional analysis revealed that upon NHS incubation, CRASP-3 or CRASP-5 expressing borreliae were killed by complement. CONCLUSIONS/SIGNIFICANCE: In the absence of CFH and the presence of CFHR1, CFHR2 and CFHR5, assembly and integration of the membrane attack complex was not efficiently inhibited indicating that CFH in co-operation with CFHR1, CFHR2 and CFHR5 supports complement evasion of B. burgdorferi.

  17. The immunity-related GTPases in mammals: a fast-evolving cell-autonomous resistance system against intracellular pathogens.

    Science.gov (United States)

    Hunn, Julia P; Feng, Carl G; Sher, Alan; Howard, Jonathan C

    2011-02-01

    The immunity-related GTPases (IRGs) belong to the family of large, interferon-inducible GTPases and constitute a cell-autonomous resistance system essential for the control of vacuolar pathogens like Toxoplasma gondii in mice. Recent results demonstrated that numerous IRG members accumulate collaboratively at the parasitophorous vacuole of invading T. gondii leading to the destruction of the vacuole and the parasite and subsequent necrotic host cell death. Complex regulatory interactions between different IRG proteins are necessary for these processes. Disturbance of this finely balanced system, e.g., by single genetic deficiency for the important negative regulator Irgm1 or the autophagic regulator Atg5, leads to spontaneous activation of the effector IRG proteins when induced by IFNγ. This activation has cytotoxic consequences resulting in a severe lymphopenia, macrophage defects, and failure of the adaptive immune system in Irgm1-deficient mice. However, alternative functions in phagosome maturation and induction of autophagy have been proposed for Irgm1. The IRG system has been studied primarily in mice, but IRG genes are present throughout the mammalian lineage. Interestingly, the number, type, and diversity of genes present differ greatly even between closely related species, probably reflecting intimate host-pathogen coevolution driven by an armed race between the IRG resistance proteins and pathogen virulence factors. IRG proteins are targets for polymorphic T. gondii virulence factors, and genetic variation in the IRG system between different mouse strains correlates with resistance and susceptibility to virulent T. gondii strains.

  18. CCND1 mutations increase protein stability and promote ibrutinib resistance in mantle cell lymphoma.

    Science.gov (United States)

    Mohanty, Atish; Sandoval, Natalie; Das, Manasi; Pillai, Raju; Chen, Lu; Chen, Robert W; Amin, Hesham M; Wang, Michael; Marcucci, Guido; Weisenburger, Dennis D; Rosen, Steven T; Pham, Lan V; Ngo, Vu N

    2016-11-08

    Mantle cell lymphoma (MCL) is characterized by the t(11;14) translocation, which leads to deregulated expression of the cell cycle regulatory protein cyclin D1 (CCND1). Genomic studies of MCL have also identified recurrent mutations in the coding region of CCND1. However, the functional consequence of these mutations is not known. Here, we showed that, compared to wild type (WT), single E36K, Y44D or C47S CCND1 mutations increased CCND1 protein levels in MCL cell lines. Mechanistically, these mutations stabilized CCND1 protein through attenuation of threonine-286 phosphorylation, which is important for proteolysis through the ubiquitin-proteasome pathway. In addition, the mutant proteins preferentially localized to the nucleus. Interestingly, forced expression of WT or mutant CCND1 increased resistance of MCL cell lines to ibrutinib, an FDA-approved Bruton tyrosine kinase inhibitor for MCL treatment. The Y44D mutant sustained the resistance to ibrutinib even at supraphysiologic concentrations (5-10 μM). Furthermore, primary MCL tumors with CCND1 mutations also expressed stable CCND1 protein and were resistant to ibrutinib. These findings uncover a new mechanism that is critical for the regulation of CCND1 protein levels, and is directly relevant to primary ibrutinib resistance in MCL.

  19. Resistance-Strain Relation On Vanadium Dioxide Thin Films

    Science.gov (United States)

    Amiri, Ali; Leclair, Patrick; Gupta, Arun

    Vanadium dioxide is a strongly correlated material with a sharp metal to insulator transition at ~341 K. It is well known that the strain along c-axis can change the transition temperature, but the other effects of the strain have not been drawing much attention. In this work we have studied the effects of the strain on resistance changes in the polycrystalline and epitaxial films. Polycrystalline films of VO2 are deposited on the Pb(Mg1/3Nb2/3)0.72Ti0.28O3(001) (PMN-PT) using a SiO2 buffer layer. The strain on film is tuned by applying a bias electric field through the piezoelectric substrate, and the resistance is measured using four-probe method. The epitaxial films of VO2 are grown on TiO2 (001) and have been glued to PMN-PT substrate to transfer strain. The change in the resistance of the epitaxial films is measured to be only about 30% more than polycrystalline films for the same amount of strain. We have studied the strain-induced resistance changes as a function of temperature. we have shown that the resistance is more sensitive to strain in the metallic phase.

  20. Stable isotope labelled mass spectrometry for quantification of the relative abundances for expressed proteins induced by PeaT1

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The protein elicitor from the mycelium of Alternaria tenuissima has been isolated.The elicitor triggered resistance to the tobacco mosaic virus in tobacco by inducing relative oxygen species,but without causing hypersensitive necrosis.The elicitor is reported to impart resistance against Verticillium dahliae and to increase yield in cotton,but its mechanism is not yet clear.In this study,the stable isotope labelled mass spectrometry method was used to quantify the relative abundances of protein expression induced by PeaT1 in Arabidopsis.A significant difference in the relative abundances for the expression of different proteins related to metabolism,modification,regulatory,defense,stress and antioxidation was found in Arabidopsis.

  1. Two seven-transmembrane domain MILDEW RESISTANCE LOCUS O proteins cofunction in Arabidopsis root thigmomorphogenesis.

    Science.gov (United States)

    Chen, Zhongying; Noir, Sandra; Kwaaitaal, Mark; Hartmann, H Andreas; Wu, Ming-Jing; Mudgil, Yashwanti; Sukumar, Poornima; Muday, Gloria; Panstruga, Ralph; Jones, Alan M

    2009-07-01

    Directional root expansion is governed by nutrient gradients, positive gravitropism and hydrotropism, negative phototropism and thigmotropism, as well as endogenous oscillations in the growth trajectory (circumnutation). Null mutations in phylogenetically related Arabidopsis thaliana genes MILDEW RESISTANCE LOCUS O 4 (MLO4) and MLO11, encoding heptahelical, plasma membrane-localized proteins predominantly expressed in the root tip, result in aberrant root thigmomorphogenesis. mlo4 and mlo11 mutant plants show anisotropic, chiral root expansion manifesting as tightly curled root patterns upon contact with solid surfaces. The defect in mlo4 and mlo11 mutants is nonadditive and dependent on light and nutrients. Genetic epistasis experiments demonstrate that the mutant phenotype is independently modulated by the Gbeta subunit of the heterotrimeric G-protein complex. Analysis of expressed chimeric MLO4/MLO2 proteins revealed that the C-terminal domain of MLO4 is necessary but not sufficient for MLO4 action in root thigmomorphogenesis. The expression of the auxin efflux carrier fusion, PIN1-green fluorescent protein, the pattern of auxin-induced gene expression, and acropetal as well as basipetal auxin transport are altered at the root tip of mlo4 mutant seedlings. Moreover, addition of auxin transport inhibitors or the loss of EIR1/AGR1/PIN2 function abolishes root curling of mlo4, mlo11, and wild-type seedlings. These results demonstrate that the exaggerated root curling phenotypes of the mlo4 and mlo11 mutants depend on auxin gradients and suggest that MLO4 and MLO11 cofunction as modulators of touch-induced root tropism.

  2. The E2-like conjugation enzyme Atg3 promotes binding of IRG and Gbp proteins to Chlamydia- and Toxoplasma-containing vacuoles and host resistance.

    Directory of Open Access Journals (Sweden)

    Arun K Haldar

    Full Text Available Cell-autonomous immunity to the bacterial pathogen Chlamydia trachomatis and the protozoan pathogen Toxoplasma gondii is controlled by two families of Interferon (IFN-inducible GTPases: Immunity Related GTPases (IRGs and Guanylate binding proteins (Gbps. Members of these two GTPase families associate with pathogen-containing vacuoles (PVs and solicit antimicrobial resistance pathways specifically to the intracellular site of infection. The proper delivery of IRG and Gbp proteins to PVs requires the autophagy factor Atg5. Atg5 is part of a protein complex that facilitates the transfer of the ubiquitin-like protein Atg8 from the E2-like conjugation enzyme Atg3 to the lipid phosphatidylethanolamine. Here, we show that Atg3 expression, similar to Atg5 expression, is required for IRG and Gbp proteins to dock to PVs. We further demonstrate that expression of a dominant-active, GTP-locked IRG protein variant rescues the PV targeting defect of Atg3- and Atg5-deficient cells, suggesting a possible role for Atg proteins in the activation of IRG proteins. Lastly, we show that IFN-induced cell-autonomous resistance to C. trachomatis infections in mouse cells depends not only on Atg5 and IRG proteins, as previously demonstrated, but also requires the expression of Atg3 and Gbp proteins. These findings provide a foundation for a better understanding of IRG- and Gbp-dependent cell-autonomous resistance and its regulation by Atg proteins.

  3. Benchmarking NMR experiments: a relational database of protein pulse sequences.

    Science.gov (United States)

    Senthamarai, Russell R P; Kuprov, Ilya; Pervushin, Konstantin

    2010-03-01

    Systematic benchmarking of multi-dimensional protein NMR experiments is a critical prerequisite for optimal allocation of NMR resources for structural analysis of challenging proteins, e.g. large proteins with limited solubility or proteins prone to aggregation. We propose a set of benchmarking parameters for essential protein NMR experiments organized into a lightweight (single XML file) relational database (RDB), which includes all the necessary auxiliaries (waveforms, decoupling sequences, calibration tables, setup algorithms and an RDB management system). The database is interfaced to the Spinach library (http://spindynamics.org), which enables accurate simulation and benchmarking of NMR experiments on large spin systems. A key feature is the ability to use a single user-specified spin system to simulate the majority of deposited solution state NMR experiments, thus providing the (hitherto unavailable) unified framework for pulse sequence evaluation. This development enables predicting relative sensitivity of deposited implementations of NMR experiments, thus providing a basis for comparison, optimization and, eventually, automation of NMR analysis. The benchmarking is demonstrated with two proteins, of 170 amino acids I domain of alphaXbeta2 Integrin and 440 amino acids NS3 helicase.

  4. Resistance against Echinostoma caproni (Trematoda) secondary infections in mice is not dependent on the ileal protein production.

    Science.gov (United States)

    Cortés, Alba; Sotillo, Javier; Muñoz-Antolí, Carla; Martín-Grau, Carla; Esteban, J Guillermo; Toledo, Rafael

    2016-05-17

    Echinostoma caproni (Trematoda: Echinostomatidae) is an intestinal trematode, which has been widely employed to investigate the factors determining the rejection of intestinal helminths. Protein production patterns of intestinal epithelial cells are related to the infection-induced changes that determine the course of E. caproni infections. Herein, we compare the protein production profiles in the ileum of four experimental groups of mice: control; infected; dewormed and reinfected. Worm burdens were significantly lower in secondary infections, confirming the generation of partial resistance to homologous secondary infections in mice. However, quantitative comparison by 2D-DIGE showed that the protein production profile is similar in control and dewormed mice, and after primary and secondary E. caproni infections. These results showed that, unexpectedly, protein production changes in E. caproni infections are not responsible of resistance development. Fifty-one protein spots were differentially produced between control/treated and infected/reinfected mice and 37 of them were identified by mass spectrometry. The analysis of differentially abundant proteins indicate that cell metabolism and the regulation of proliferation and cell death are the most affected processes after primary and secondary E. caproni infections. These results provide new insights into the proteins involved in the regulation of tissue homeostasis after intestinal infection. Intestinal helminthiases are highly prevalent parasitic infections with about 1 billion people infected worldwide. In this scenario, better understanding of host-parasite relationships is needed to elucidate the factors that determine intestinal helminth rejection. The intestinal trematode Echinostoma caproni has been broadly employed in this field, with resistance against secondary homologous infections reported in mice. In this paper, new insights are provided in the regulation of tissue homeostasis after intestinal

  5. Timing of postexercise protein intake is important for muscle hypertrophy with resistance training in elderly humans

    DEFF Research Database (Denmark)

    Esmarck, Birgitte; Olsen, Steen Schytte

    2001-01-01

    remains unresolved. 2. The study investigated the importance of immediate (P0) or delayed (P2) intake of an oral protein supplement upon muscle hypertrophy and strength over a period of resistance training in elderly males. 3. Thirteen men (age, 74 ± 1 years; body mass index (BMI), 25 ± 1 kg m−2 (means...... ± S.E.M.)) completed a 12 week resistance training programme (3 times per week) receiving oral protein in liquid form (10 g protein, 7 g carbohydrate, 3 g fat) immediately after (P0) or 2 h after (P2) each training session. Muscle hypertrophy was evaluated by magnetic resonance imaging (MRI) and from...... for the development of hypertrophy in skeletal muscle of elderly men in response to resistance training....

  6. Cloning and characterization of the rat multidrug resistance-associated protein 1

    OpenAIRE

    Yang, Ziping; Li, Cheryl S. W.; Shen, Danny D.; Ho, Rodney J. Y.

    2002-01-01

    Multidrug resistance-associated protein 1 (MRP1) was originally shown to confer resistance of human tumor cells to a broad range of natural product anticancer drugs. MRP1 has also been shown to mediate efflux transport of glutathione and glucuronide conjugates of drugs and endogenous substrates. An ortholog of MRP1 in the mouse has been cloned and characterized. Significant functional differences between murine and human MRP1 have been noted. Since drug disposition and pharmacology studies of...

  7. Role of Spore Coat Proteins in the Resistance of Bacillus subtilis Spores to Caenorhabditis elegans Predation▿

    OpenAIRE

    2008-01-01

    Bacterial spores are resistant to a wide range of chemical and physical insults that are normally lethal for the vegetative form of the bacterium. While the integrity of the protein coat of the spore is crucial for spore survival in vitro, far less is known about how the coat provides protection in vivo against predation by ecologically relevant hosts. In particular, assays had characterized the in vitro resistance of spores to peptidoglycan-hydrolyzing enzymes like lysozyme that are also imp...

  8. Molecular and hormonal responses and adaptation to resistance and protein nutrition in young and older men

    OpenAIRE

    Hulmi, Juha

    2009-01-01

    The aim of the present study was to investigate the mechanisms leading to muscle hypertrophy in humans by studying local muscle molecular and systemic hormonal responses to a single bout of heavy resistance exercise (RE) and to long-term resistance training (RT) with or without protein supplementation in a randomized controlled double-blinded design. In line with earlier studies, heavy RT for 21 weeks led to muscle hypertrophy and an increase in muscle strength in both young and older men. Wh...

  9. Novel Vip3-related protein from Bacillus thuringiensis.

    Science.gov (United States)

    Rang, Cécile; Gil, Patricia; Neisner, Nathalie; Van Rie, Jeroen; Frutos, Roger

    2005-10-01

    A novel vip3-related gene was identified in Bacillus thuringiensis. This novel gene is 2,406 bp long and codes for a 91-kDa protein (801 amino acids). This novel protein exhibits between 61 and 62% similarity with Vip3A proteins and is designated Vip3Ba1. Vip3Ba1 has several specific features. Differences between Vip3Ba1 and the Vip3A proteins are spread throughout the sequence but are more frequent in the C-terminal part from amino acid 456 onward. The regions containing the two proteolytic processing sites, which are highly conserved among the Vip3A toxins, are markedly different in Vip3Ba1. The pattern DCCEE (Asp Cys Cys Glu Glu) is repeated four times between position 463 and 483 in Vip3Ba1, generating the sequence 463-DCCEEDCCEEDCCEEDCCEE-483. This sequence, which is rich in negatively charged amino acids, also contains 73% of the cysteines present in Vip3Ba1. This repeated sequence is not present in Vip3A proteins. The Vip3Ba1protein was produced in Escherichia coli and tested against Ostrinia nubilalis and Plutella xylostella, and it generated significant growth delays but had no larvicidal effect, indicating that its host range might be different than that of Vip3A proteins.

  10. Polygalacturonase-inhibitor proteins in pearl millet: possible involvement in resistance against downy mildew

    Institute of Scientific and Technical Information of China (English)

    S. Ashok Prabhu; K. Ramachandra Kini; S. Niranjan Raj; Bruno M. Moerschbacher; H. S. Shetty

    2012-01-01

    Polygalacturonase-inhibitor protein (PGIP) is a defense protein found in plant cell walls.It prevents the degradation of pectin by modulating the endo-polygalacturonase activity.The present study has used heterologous antibean PGIP probes to investigate the role of PGIP in pearl millet [Pennisetum glaucum (L) R.Br.] resistance against downy mildew caused by oomycete pathogen Sclerospora graminicola (Sacc.) Schroet.Northern blot analysis using bean pgip2 DNA fragment as probe showed an early and marked induction of transcripts (~1.2 kb) upon pathogen-inoculation in pearl millet cultivar resistant to downy mildew,with the maximum level observed at 24 and 48 h post-inoculation (h.p.i.).Western blot analysis of pearl millet total cell wall proteins using antibodies against bean PGIP showed the presence of a major band of ~43 kDa,and several minor ones.The protein accumulation was higher in resistant seedlings than in susceptible seedlings with a differential expression observed only in the case of incompatible interaction.lmmunocytochemical localization in epidermal peelings of coleoptiles and tissue-printing showed a similar trend in the PGIP accumulation.PGIP was found to localize in the epidermal as well as in the vascular regions of tissues.Higher accumulation was observed in the stomatal guard cells of resistant cultivar inoculated with the pathogen.PGIP activity of pearl millet total protein extracts when assayed against Aspergillus niger PG displayed differential PG inhibitory activities between the resistant and suceptible cultivars with resistant sample showing the highest inhibition of 16%,post-pathogen treatment.Thus,PGIP appeared to be an important player in pearl millet-S,graminicola interaction leading to host resistance.

  11. Experimental Alcohol-Related Peripheral Neuropathy: Role of Insulin/IGF Resistance

    Directory of Open Access Journals (Sweden)

    James Gilchrist

    2012-08-01

    Full Text Available The mechanisms of alcohol-related peripheral neuropathy (ALPN are poorly understood. We hypothesize that, like alcohol-related liver and brain degeneration, ALPN may be mediated by combined effects of insulin/IGF resistance and oxidative stress. Adult male Long Evans rats were chronically pair-fed with diets containing 0% or 37% ethanol (caloric, and subjected to nerve conduction studies. Chronic ethanol feeding slowed nerve conduction in the tibial (p = 0.0021 motor nerve, and not plantar sensory nerve, but it did not affect amplitude. Histological studies of the sciatic nerve revealed reduced nerve fiber diameters with increased regenerative sprouts, and denervation myopathy in ethanol-fed rats. qRT-PCR analysis demonstrated reduced mRNA levels of insulin, IGF-1, and IGF-2 polypeptides, IGF-1 receptor, and IRS2, and ELISAs revealed reduced immunoreactivity for insulin and IGF-1 receptors, IRS-1, IRS-4, myelin-associated glycoprotein, and tau in sciatic nerves of ethanol-fed rats (all p < 0.05 or better. The findings suggest that ALPN is characterized by (1 slowed conduction velocity with demyelination, and a small component of axonal degeneration; (2 impaired trophic factor signaling due to insulin and IGF resistance; and (3 degeneration of myelin and axonal cytoskeletal proteins. Therefore, ALPN is likely mediated by molecular and signal transduction abnormalities similar to those identified in alcoholic liver and brain degeneration.

  12. Neisseria gonorrhoeae strain with high-level resistance to spectinomycin due to a novel resistance mechanism (mutated ribosomal protein S5) verified in Norway.

    Science.gov (United States)

    Unemo, Magnus; Golparian, Daniel; Skogen, Vegard; Olsen, Anne Olaug; Moi, Harald; Syversen, Gaute; Hjelmevoll, Stig Ove

    2013-02-01

    Gonorrhea may become untreatable, and new treatment options are essential. Verified resistance to spectinomycin is exceedingly rare. However, we describe a high-level spectinomycin-resistant (MIC, >1,024 μg/ml) Neisseria gonorrhoeae strain from Norway with a novel resistance mechanism. The resistance determinant was a deletion of codon 27 (valine) and a K28E alteration in the ribosomal protein 5S. The traditional spectinomycin resistance gene (16S rRNA) was wild type. Despite this exceedingly rare finding, spectinomycin available for treatment of ceftriaxone-resistant urogenital gonorrhea would be very valuable.

  13. Decreased PARP and procaspase-2 protein levels are associated with cellular drug resistance in childhood acute lymphoblastic leukemia.

    Science.gov (United States)

    Holleman, Amy; den Boer, Monique L; Kazemier, Karin M; Beverloo, H Berna; von Bergh, Anne R M; Janka-Schaub, Gritta E; Pieters, Rob

    2005-09-01

    Drug resistance in childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) is associated with impaired ability to induce apoptosis. To elucidate causes of apoptotic defects, we studied the protein expression of Apaf-1, procaspases-2, -3, -6, -7, -8, -10, and poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) in cells from children with acute lymphoblastic leukemia (ALL; n = 43) and acute myeloid leukemia (AML; n = 10). PARP expression was present in all B-lineage samples, but absent in 4 of 15 T-lineage ALL samples and 3 of 10 AML cases, which was not caused by genomic deletions. PARP expression was a median 7-fold lower in T-lineage ALL (P < .001) and 10-fold lower in AML (P < .001) compared with B-lineage ALL. PARP expression was 4-fold lower in prednisolone, vincristine and L-asparaginase (PVA)-resistant compared with PVA-sensitive ALL patients (P < .001). Procaspase-2 expression was 3-fold lower in T-lineage ALL (P = .022) and AML (P = .014) compared with B-lineage ALL. In addition, procaspase-2 expression was 2-fold lower in PVA-resistant compared to PVA-sensitive ALL patients (P = .042). No relation between apoptotic protease-activating factor 1 (Apaf-1), procaspases-3, -6, -7, -8, -10, and drug resistance was found. In conclusion, low baseline expression of PARP and procaspase-2 is related to cellular drug resistance in childhood acute lymphoblastic leukemia.

  14. Landscape mapping of functional proteins in insulin signal transduction and insulin resistance: a network-based protein-protein interaction analysis.

    Directory of Open Access Journals (Sweden)

    Chiranjib Chakraborty

    Full Text Available The type 2 diabetes has increased rapidly in recent years throughout the world. The insulin signal transduction mechanism gets disrupted sometimes and it's known as insulin-resistance. It is one of the primary causes associated with type-2 diabetes. The signaling mechanisms involved several proteins that include 7 major functional proteins such as INS, INSR, IRS1, IRS2, PIK3CA, Akt2, and GLUT4. Using these 7 principal proteins, multiple sequences alignment has been created. The scores between sequences also have been developed. We have constructed a phylogenetic tree and modified it with node and distance. Besides, we have generated sequence logos and ultimately developed the protein-protein interaction network. The small insulin signal transduction protein arrangement shows complex network between the functional proteins.

  15. Colistin resistance associated with outer membrane protein change in Klebsiella pneumoniae and Enterobacter asburiae.

    Science.gov (United States)

    Kádár, Béla; Kocsis, Béla; Tóth, Ákos; Kristóf, Katalin; Felső, Péter; Kocsis, Béla; Böddi, Katalin; Szabó, Dóra

    2017-06-01

    In this study, outer membrane proteins (OMPs) of colistin-resistant Klebsiella pneumoniae and Enterobacter asburiae were analyzed. One colistin-susceptible and three colistin-resistant K. pneumoniae sequence type 258 strains as well as one colistin-susceptible E. asburiae and its colistin-heteroresistant counterpart strain were involved in the study. OMP analysis of each strain was performed by microchip method. Matrix-assisted laser desorption ionization time of flight/mass spectrometry (MALDI-TOF/MS) investigation was carried out after separation of OMPs by two-dimensional gel electrophoresis and in-gel digestion. The MALDI-TOF/MS analysis of OMPs in the colistin-susceptible K. pneumoniae found 16 kDa proteins belonging to the LysM domain/BON superfamily, as well as DNA starvation proteins, whereas OmpX and OmpW were detected in the colistin-resistant counterpart strains. OmpC and OmpW were detected in the colistin-susceptible E. asburiae, whereas OmpA and OmpX were identified in the colistin-resistant counterpart. This study demonstrated that OMP differences were between colistin-susceptible and -resistant counterpart strains. The altered Gram-negative cell wall may contribute to acquired colistin resistance in Enterobacteriaceae.

  16. Total Protein Profile and Drug Resistance in Candida albicans Isolated from Clinical Samples

    Directory of Open Access Journals (Sweden)

    Kamal Uddin Zaidi

    2016-01-01

    Full Text Available This study was done to assess the antifungal susceptibility of clinical isolates of Candida albicans and to evaluate its total protein profile based on morphological difference on drug resistance. Hundred and twenty clinical isolates of C. albicans from various clinical specimens were tested for susceptibility against four antifungal agents, namely, fluconazole, itraconazole, amphotericin B, and ketoconazole. A significant increase of drug resistance in clinical isolates of C. albicans was observed. The study showed 50% fluconazole and itraconazole resistance at 32 μg mL−1 with a MIC50 and MIC90 values at 34 and 47 and 36 and 49 μg mL−1, respectively. All isolates were sensitive to amphotericin B and ketoconazole. The SDS-PAGE protein profile showed a prevalent band of ~52.5 kDa, indicating overexpression of gene in 72% strains with fluconazole resistance. Since the opportunistic infections of Candida spp. are increasing along with drug resistance, the total protein profile will help in understanding the evolutionary changes in drug resistance and also to characterize them.

  17. DBC2 resistance is achieved by enhancing 26S proteasome-mediated protein degradation.

    Science.gov (United States)

    Collado, Denise; Yoshihara, Takashi; Hamaguchi, Masaaki

    2007-08-31

    Tumor suppressor gene DBC2 stops growth of tumor cells through regulation of CCND1. Interference of CCND1 down-regulation prevented growth arrest caused by DBC2 [T. Yoshihara, D. Collado, M. Hamaguchi, Cyclin D1 down-regulation is essential for DBC2's tumor suppressor function, Biochemical and biophysical research communications 358 (2007) 1076-1079]. It was also noted that DBC2 resistant cells eventually arose after repeated induction of DBC2 with muristerone A treatment [M. Hamaguchi, J.L. Meth, C. Von Klitzing, W. Wei, D. Esposito, L. Rodgers, T. Walsh, P. Welcsh, M.C. King, M.H. Wigler, DBC2, a candidate for a tumor suppressor gene involved in breast cancer, Proc. Natl. Acad. Sci. USA 99 (2002) 13647-13652]. In order to elucidate the mechanism of resistance acquisition, we analyzed DBC2 sensitive and resistant cells derived from the same progenitor cells (T-47D). We discovered that DBC2 protein was abundantly expressed in the sensitive cells when DBC2 was induced. In contrast, it was undetectable by western blot analysis in the resistant cells. We confirmed that the inducible gene expression system was responsive in both cells by detecting induced GFP. Additionally, inhibition of 26S proteasome by MG132 revealed production of DBC2 protein in the resistant cells. These findings indicate that the resistant T-47D cells survive DBC2 induction by rapid destruction of DBC2 through 26S proteasome-mediated protein degradation.

  18. Proteomics Analysis of Ovarian Cancer Cell Lines and Tissues Reveals Drug Resistance-associated Proteins

    Science.gov (United States)

    CRUZ*, ISA N.; COLEY*, HELEN M.; KRAMER, HOLGER B.; MADHURI, THUMULURU KAVITAH; SAFUWAN, NUR A.M.; ANGELINO, ANA RITA; YANG, MIN

    2016-01-01

    Background: Carboplatin and paclitaxel form the cornerstone of chemotherapy for epithelial ovarian cancer, however, drug resistance to these agents continues to present challenges. Despite extensive research, the mechanisms underlying this resistance remain unclear. Materials and Methods: A 2D-gel proteomics method was used to analyze protein expression levels of three human ovarian cancer cell lines and five biopsy samples. Representative proteins identified were validated via western immunoblotting. Ingenuity pathway analysis revealed metabolomic pathway changes. Results: A total of 189 proteins were identified with restricted criteria. Combined treatment targeting the proteasome-ubiquitin pathway resulted in re-sensitisation of drug-resistant cells. In addition, examination of five surgical biopsies of ovarian tissues revealed α-enolase (ENOA), elongation factor Tu, mitochondrial (EFTU), glyceraldehyde-3-phosphate dehydrogenase (G3P), stress-70 protein, mitochondrial (GRP75), apolipoprotein A-1 (APOA1), peroxiredoxin (PRDX2) and annexin A (ANXA) as candidate biomarkers of drug-resistant disease. Conclusion: Proteomics combined with pathway analysis provided information for an effective combined treatment approach overcoming drug resistance. Analysis of cell lines and tissues revealed potential prognostic biomarkers for ovarian cancer. *These Authors contributed equally to this study. PMID:28031236

  19. Improvement of the relative entropy based protein folding method

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The "relative entropy" has been used as a minimization function to predict the tertiary structure of a protein backbone, and good results have been obtained. However, in our previous work, the ensemble average of the contact potential was estimated by an approximate calculation. In order to improve the theoretical integrity of the relative-entropy-based method, a new theoretical calculation method of the ensemble average of the contact potential was presented in this work, which is based on the thermodynamic perturbation theory. Tests of the improved algorithm were performed on twelve small proteins. The root mean square deviations of the predicted versus the native structures from Protein Data Bank range from 0.40 to 0.60 nm. Compared with the previous approximate values, the average prediction accuracy is improved by 0.04 nm.

  20. Improvement of the relative entropy based protein folding method

    Institute of Scientific and Technical Information of China (English)

    QI LiSheng; SU JiGuo; CHEN WeiZu; WANG CunXin

    2009-01-01

    The "relative entropy" has been used as a minimization function to predict the tertiary structure of a protein backbone, and good results have been obtained. However, in our previous work, the ensemble average of the contact potential was estimated by an approximate calculation. In order to improve the theoretical integrity of the relative-entropy-based method, a new theoretical calculation method of the ensemble average of the contact potential was presented in this work, which is based on the thermodynamic perturbation theory. Testa of the improved algorithm were performed on twelve small proteins. The root mean square deviations of the predicted versus the native structures from Protein Data Bank range from 0.40 to 0.60 nm. Compared with the previous approximate values, the average prediction accuracy is improved by 0.04 nm.

  1. Factor H-related proteins determine complement-activating surfaces.

    Science.gov (United States)

    Józsi, Mihály; Tortajada, Agustin; Uzonyi, Barbara; Goicoechea de Jorge, Elena; Rodríguez de Córdoba, Santiago

    2015-06-01

    Complement factor H-related proteins (FHRs) are strongly associated with different diseases involving complement dysregulation, which suggests a major role for these proteins regulating complement activation. Because FHRs are evolutionarily and structurally related to complement inhibitor factor H (FH), the initial assumption was that the FHRs are also negative complement regulators. Whereas weak complement inhibiting activities were originally reported for these molecules, recent developments indicate that FHRs may enhance complement activation, with important implications for the role of these proteins in health and disease. We review these findings here, and propose that FHRs represent a complex set of surface recognition molecules that, by competing with FH, provide improved discrimination of self and non-self surfaces and play a central role in determining appropriate activation of the complement pathway.

  2. The heat shock protein/chaperone network and multiple stress resistance

    KAUST Repository

    Jacob, Pierre

    2016-11-15

    Crop yield has been greatly enhanced during the last century. However, most elite cultivars are adapted to temperate climates and are not well suited to more stressful conditions. In the context of climate change, stress resistance is a major concern. To overcome these difficulties, scientists may help breeders by providing genetic markers associated with stress resistance. However, multi-stress resistance cannot be obtained from the simple addition of single stress resistance traits. In the field, stresses are unpredictable and several may occur at once. Consequently, the use of single stress resistance traits is often inadequate. Although it has been historically linked with the heat stress response, the heat shock protein (HSP)/chaperone network is a major component of multiple stress responses. Among the HSP/chaperone

  3. Protein kinases: mechanisms and downstream targets in inflammation-mediated obesity and insulin resistance.

    Science.gov (United States)

    Nandipati, Kalyana C; Subramanian, Saravanan; Agrawal, Devendra K

    2017-02-01

    Obesity-induced low-grade inflammation (metaflammation) impairs insulin receptor signaling. This has been implicated in the development of insulin resistance. Insulin signaling in the target tissues is mediated by stress kinases such as p38 mitogen-activated protein kinase, c-Jun NH2-terminal kinase, inhibitor of NF-kB kinase complex β (IKKβ), AMP-activated protein kinase, protein kinase C, Rho-associated coiled-coil containing protein kinase, and RNA-activated protein kinase. Most of these kinases phosphorylate several key regulators in glucose homeostasis. The phosphorylation of serine residues in the insulin receptor and IRS-1 molecule results in diminished enzymatic activity in the phosphatidylinositol 3-kinase (PI3K)/Akt pathway. This has been one of the key mechanisms observed in the tissues that are implicated in insulin resistance especially in type 2 diabetes mellitus (T2-DM). Identifying the specific protein kinases involved in obesity-induced chronic inflammation may help in developing the targeted drug therapies to minimize the insulin resistance. This review is focused on the protein kinases involved in the inflammatory cascade and molecular mechanisms and their downstream targets with special reference to obesity-induced T2-DM.

  4. Relative importance of aerobic versus resistance training for healthy aging

    Science.gov (United States)

    This review will focus on the importance of aerobic and resistance modes of physical activity for healthy aging as supported by findings in 2007. In line with public health recommendations, several studies in 2007 employed an exercise paradigm that combined both modes of physical activity. While a...

  5. Crystallization of DIR1, a LTP2-like resistance signalling protein from Arabidopsis thaliana

    Energy Technology Data Exchange (ETDEWEB)

    Lascombe, Marie-Bernard, E-mail: marie-bernard.lascombe@univ-paris5.fr [UMR 8015 CNRS, Faculté de Pharmacie, 4 Avenue de l’Observatoire, 75006 Paris (France); Buhot, Nathalie [John Innes Centre, Norwich NR4 7UH (United Kingdom); Bakan, Bénédicte; Marion, Didier [Unité de Recherches Biopolymères, Interactions, Assemblages, INRA, La Géraudière, BP 71627 (France); Blein, Jean Pierre [Phytopharmacie et Biochimie des Interactions Cellulaires, UMR 692 CNRS, INRA, BP 86510, Dijon CEDEX (France); Lamb, Chris J. [John Innes Centre, Norwich NR4 7UH (United Kingdom); Prangé, Thierry [UMR 8015 CNRS, Faculté de Pharmacie, 4 Avenue de l’Observatoire, 75006 Paris (France)

    2006-07-01

    DIR1, a putative LTP2 protein from Arabidopsis thaliana implicated in systemic acquired resistance in planta, has been crystallized in space group P2{sub 1}2{sub 1}2{sub 1} with one molecule per asymmetric unit. DIR1, a putative LTP2 protein from Arabidopsis thaliana implicated in systemic acquired resistance in planta, has been crystallized in space group P2{sub 1}2{sub 1}2{sub 1} with one molecule per asymmetric unit. The crystals diffract to a resolution of 1.6 Å.

  6. Expression of Lung Resistance Protein (LRP) Gene in Hepatocellular Carcinoma and Its Significance

    Institute of Scientific and Technical Information of China (English)

    WANGBailin; CHENXiaoping; ZHAIShuping; YANGHaiyan; ZHONGYong

    2004-01-01

    To study the multidrug resistance (MDR) mechanism of lung resistance protein (LRP) gene in hepatocellular carcinoma (HCC), and the relations among the expression of the LRP gene and clinicopathologic features, the influence of ~-fetoprotein (AFP), and prognosis of patients who received adjuvant chemotherapy after resection of HCC. Methods: The expression of the LRP gene encoding LRP and mRNA LRP was detected in tissues from 54 untreated patients with HCC, adjacent tissues from 24 patients with HCC and archival paraffin-embedded tissues from 12 patients with posthepatitic cirrhosis. The relationship between the LRP gene expression and the change of AFP level was analyzed in the 24 postoperative HCC patients whose AFP was measured after 2 weeks. All of the HCC patients were followed up. Results: The percentage of positive expression of LRP and mRNA LRP in the 3 tissues was 61.1%, 33.3%, 16.7%, and 75.9%, 37.5%, 33.3% respectively. There was significant difference between the untreated HCC tissue and other tissues (P0.05), but the expression was related to the degree of differentiation of HCC (P<0.05). The effective rate of AFP in the LRP gene positive expression group or in postoperative chemotherapeutic patients was very lower than that in the negative group (P<0.05). Although the mean survival time of postoperative HCC patients in negative LRP gene expression group was longer than that of positive group, there was no difference between them (P<0.05). Conclusion: LRP gene expression is related to MDR of HCC and initiates the intrinsic MDR. Detection of LRP gene expression is of great guiding significance in accessing chemotherapeutic resistance of HCC. As an index to chemotherapy of HCC, detection of LRP expression provides evidence for making individual chemotherapeutic treatment,and reversing MDR in HCC. Although LRP gene expression correlates with the tumor differential degree (P<0.05), it perhaps does not relate with the prognosis of HCC patients.

  7. Fluorescopic evaluation of protein-lipid relations in cellular signalling.

    NARCIS (Netherlands)

    Pap, E.H.W.

    1994-01-01

    IntroductionCellular communication is partly mediated through the modulation of protein activity, structure and dynamics by lipids. In contrast to the biochemical aspects of lipid signalling, relatively little is known about the physical properties of the "signal" lipids (lipids involved in cellular

  8. Dose-related selection of fluoroquinolone-resistant Escherichia coli.

    Science.gov (United States)

    Olofsson, Sara K; Marcusson, Linda L; Strömbäck, Ann; Hughes, Diarmaid; Cars, Otto

    2007-10-01

    To investigate the effects of clinically used doses of norfloxacin, ciprofloxacin and moxifloxacin on survival and selection in Escherichia coli populations containing fluoroquinolone-resistant subpopulations and to measure the value of the pharmacodynamic index AUC/mutant prevention concentration (MPC) that prevents the growth of pre-existing resistant mutants. Mixed cultures of susceptible wild-type and isogenic single (gyrA S83L) or double (gyrA S83L, Delta marR) fluoroquinolone-resistant mutants were exposed to fluoroquinolones for 24 h in an in vitro kinetic model. Antibiotic concentrations modelled pharmacokinetics attained with clinical doses. All tested doses eradicated the susceptible wild-type strain. Norfloxacin 200 mg administered twice daily selected for both single and double mutants. Ciprofloxacin 250 mg administered twice daily eradicated the single mutant, but not the double mutant. For that, 750 mg administered twice daily was required. Moxifloxacin 400 mg once daily eliminated the single mutant, but did not completely remove the double mutant. The MPC of ciprofloxacin was determined and based on those dose simulations that eradicated mutant subpopulations, an AUC/MPC(wild-type) of 35 prevented selection of the single mutant, whereas an AUC/MPC(single mutant) of 14 (equivalent to an AUC/MPC(wild-type) of 105) prevented selection of the double mutant. All tested clinical dosing regimens were effective in eradicating susceptible bacteria, but ciprofloxacin 750 mg twice daily was the only dose that prevented the selection of single- and double-resistant E. coli mutants. Thus, among approved fluoroquinolone dosing regimens, some are significantly more effective than others in exceeding the mutant selection window and preventing the enrichment of resistant mutants.

  9. Transfer of antibiotic-resistance genes via phage-related mobile elements.

    Science.gov (United States)

    Brown-Jaque, Maryury; Calero-Cáceres, William; Muniesa, Maite

    2015-05-01

    Antibiotic resistance is a major concern for society because it threatens the effective prevention of infectious diseases. While some bacterial strains display intrinsic resistance, others achieve antibiotic resistance by mutation, by the recombination of foreign DNA into the chromosome or by horizontal gene acquisition. In many cases, these three mechanisms operate together. Several mobile genetic elements (MGEs) have been reported to mobilize different types of resistance genes and despite sharing common features, they are often considered and studied separately. Bacteriophages and phage-related particles have recently been highlighted as MGEs that transfer antibiotic resistance. This review focuses on phages, phage-related elements and on composite MGEs (phages-MGEs) involved in antibiotic resistance mobility. We review common features of these elements, rather than differences, and provide a broad overview of the antibiotic resistance transfer mechanisms observed in nature, which is a necessary first step to controlling them.

  10. Mycobacterium fluoroquinolone resistance protein B, a novel small GTPase, is involved in the regulation of DNA gyrase and drug resistance

    Science.gov (United States)

    Tao, Jun; Han, Jiao; Wu, Hanyu; Hu, Xinling; Deng, Jiaoyu; Fleming, Joy; Maxwell, Anthony; Bi, Lijun; Mi, Kaixia

    2013-01-01

    DNA gyrase plays a vital role in resolving DNA topological problems and is the target of antibiotics such as fluoroquinolones. Mycobacterium fluoroquinolone resistance protein A (MfpA) from Mycobacterium smegmatis is a newly identified DNA gyrase inhibitor that is believed to confer intrinsic resistance to fluoroquinolones. However, MfpA does not prevent drug-induced inhibition of DNA gyrase in vitro, implying the involvement of other as yet unknown factors. Here, we have identified a new factor, named Mycobacterium fluoroquinolone resistance protein B (MfpB), which is involved in the protection of DNA gyrase against drugs both in vivo and in vitro. Genetic results suggest that MfpB is necessary for MfpA protection of DNA gyrase against drugs in vivo; an mfpB knockout mutant showed greater susceptibility to ciprofloxacin than the wild-type, whereas a strain overexpressing MfpA and MfpB showed higher loss of susceptibility. Further biochemical characterization indicated that MfpB is a small GTPase and its GTP bound form interacts directly with MfpA and influences its interaction with DNA gyrase. Mutations in MfpB that decrease its GTPase activity disrupt its protective efficacy. Our studies suggest that MfpB, a small GTPase, is required for MfpA-conferred protection of DNA gyrase. PMID:23275532

  11. Relation of resistin levels with C-reactve protein, homocysteine and uric acid in smokers and non-smokers

    Directory of Open Access Journals (Sweden)

    Onur Esbah

    2011-01-01

    Conclusions: We found that smoking may have influence on resistin levels and in smokers, insulin resistance is related to resistin levels, but in smoker and non-smokers body mass may not have any association with resistin. Resistin also may not have a role in C-reactive protein, homocysteine and uric acid levels both in smokers and non-smokers.

  12. Dietary protein safety and resistance exercise: what do we really know?

    Directory of Open Access Journals (Sweden)

    Lowery Lonnie M

    2009-01-01

    Full Text Available Abstract Resistance trainers continue to receive mixed messages about the safety of purposely seeking ample dietary protein in their quest for stimulating protein synthesis, improving performance, or maintaining health. Despite protein's lay popularity and the routinely high intakes exhibited by strength athletes, liberal and purposeful protein consumption is often maligned by "experts". University textbooks, instructors, and various forms of literature from personal training groups and athletic organizations continue to use dissuasive language surrounding dietary protein. Due to the widely known health benefits of dietary protein and a growing body of evidence on its safety profile, this is unfortunate. In response, researchers have critiqued unfounded educational messages. As a recent summarizing example, the International Society of Sports Nutrition (ISSN Position Stand: Protein and Exercise reviewed general literature on renal and bone health. The concluding remark that "Concerns that protein intake within this range [1.4 – 2.0 g/kg body weight per day] is unhealthy are unfounded in healthy, exercising individuals." was based largely upon data from non-athletes due to "a lack of scientific evidence". Future studies were deemed necessary. This assessment is not unique in the scientific literature. Investigators continue to cite controversy, debate, and the lack of direct evidence that allows it. This review discusses the few existing safety studies done specific to athletes and calls for protein research specific to resistance trainers. Population-specific, long term data will be necessary for effective education in dietetics textbooks and from sports governing bodies.

  13. Biomolecular Principles of Matrix Assembly Related to Fracture Resistance

    Science.gov (United States)

    2013-06-24

    mM NaHCO3 / Na2CO3 buffer. For comparison, we present RH values obtained in the same buffer/pH solutions for bovine erythrocyte carbonic...of amino acid spins systems are indicated on the plots. intrinsically disordered protein (Figure 2) that is fold-inducible and assembles to form... disordered supramolecular complexes that possess a high degree of dimensional heterogeneity (Figures 2A, 3). These protein assemblies are “plastic

  14. Resistance or Disconnection? A Relational-Cultural Approach to Supervisee Anxiety and Nondisclosure

    Science.gov (United States)

    Abernethy, Catherine; Cook, Katrina

    2011-01-01

    Supervisee anxiety and resistance have long presented counselor supervisors with a dilemma in supporting the professional growth and client care of their supervisees. With a more contemporary and cultural perspective, relational-cultural theory (RCT) offers a relational approach for reframing supervisee anxiety and resistance of…

  15. Involvement of the Eukaryote-Like Kinase-Phosphatase System and a Protein That Interacts with Penicillin-Binding Protein 5 in Emergence of Cephalosporin Resistance in Cephalosporin-Sensitive Class A Penicillin-Binding Protein Mutants in Enterococcus faecium

    Directory of Open Access Journals (Sweden)

    Charlene Desbonnet

    2016-04-01

    Full Text Available The intrinsic resistance of Enterococcus faecium to ceftriaxone and cefepime (here referred to as “cephalosporins” is reliant on the presence of class A penicillin-binding proteins (Pbps PbpF and PonA. Mutants lacking these Pbps exhibit cephalosporin susceptibility that is reversible by exposure to penicillin and by selection on cephalosporin-containing medium. We selected two cephalosporin-resistant mutants (Cro1 and Cro2 of class A Pbp-deficient E. faecium CV598. Genome analysis revealed changes in the serine-threonine kinase Stk in Cro1 and a truncation in the associated phosphatase StpA in Cro2 whose respective involvements in resistance were confirmed in separate complementation experiments. In an additional effort to identify proteins linked to cephalosporin resistance, we performed tandem affinity purification using Pbp5 as bait in penicillin-exposed E. faecium; these experiments yielded a protein designated Pbp5-associated protein (P5AP. Transcription of the P5AP gene was increased after exposure to penicillin in wild-type strains and in Cro2 and suppressed in Cro2 complemented with the wild-type stpA. Transformation of class A Pbp-deficient strains with the plasmid-carried P5AP gene conferred cephalosporin resistance. These data suggest that Pbp5-associated cephalosporin resistance in E. faecium devoid of typical class A Pbps is related to the presence of P5AP, whose expression is influenced by the activity of the serine-threonine phosphatase/kinase system.

  16. Purification of novel protein elicitor from Botrytis cinerea that induces disease resistance and drought tolerance in plants.

    Science.gov (United States)

    Zhang, Yunhua; Yang, Xiufen; Liu, Quan; Qiu, Dewen; Zhang, Yuliang; Zeng, Hongmei; Yuan, Jingjing; Mao, Jianjun

    2010-02-28

    PebC1, a novel protein elicitor was isolated and purified from the mycelium of gray mold fungus, Botrytis cinerea strain BC-4-2-2-1. The protein was eluted through HiTrap DEAE FF and RESOURCE Q anion exchange chromatography and displayed as a single band with an apparent molecular weight of 36 kDa on silver staining sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The pI of the purified protein PebC1 was determined by 2-DE and was 4.85. Three peptide segments were obtained by MALDI-TOF. Similarity, the homology matching using protein BLAST search found that two proteins, viz. XP_001593856 and XP_001551609 were having high score and covered sequence of the three peptides. Protein XP_001551609, a deduced protein nascent polypeptide-associated complex alpha-polypeptide, was more authentic because it was from Botryotinia fuckeliana that is better known as its anamorph, B.cinerea and showed 95% homology with the three polypeptides. The full cDNA sequence encoding for pebC1 (Genbank accession number FJ748868) was amplified from B. cinerea and consists of 639bp, which is same as a registered gene of XM_001551559, a nascent polypeptide-associated complex alpha-polypeptide partial mRNA. The gene encode a hypothetical protein speculated from an annotated genomic sequence from B. fuckeliana B05.10 (NW_001814507) and there is no publication about the gene. The PebC1 protein significantly promoted wheat seedling growth with an optimum protein concentration of 5 microg/mL. Root systemic activity of wheat with 4-5 leaves increased by 1.29 fold, and the wheat seedling drought resistance integrated index increased from 36.53 to 57.08 under two cycles of drought stress after treatment of PebC1. PebC1 protein at the optimum concentration of 10 microg/mL induced 69.19% disease resistance against gray mold fungus in tomato. Furthermore, phenylalanine ammonia-lyase (PAL), peroxides (POD), and polyphenol oxidase (PPO) related to plant resistance metabolism were also

  17. Virulent Diuraphis noxia Aphids Over-Express Calcium Signaling Proteins to Overcome Defenses of Aphid-Resistant Wheat Plants.

    Science.gov (United States)

    Sinha, Deepak K; Chandran, Predeesh; Timm, Alicia E; Aguirre-Rojas, Lina; Smith, C Michael

    2016-01-01

    The Russian wheat aphid, Diuraphis noxia, an invasive phytotoxic pest of wheat, Triticum aestivum, and barley, Hordeum vulgare, causes huge economic losses in Africa, South America, and North America. Most acceptable and ecologically beneficial aphid management strategies include selection and breeding of D. noxia-resistant varieties, and numerous D. noxia resistance genes have been identified in T. aestivum and H. vulgare. North American D. noxia biotype 1 is avirulent to T. aestivum varieties possessing Dn4 or Dn7 genes, while biotype 2 is virulent to Dn4 and avirulent to Dn7. The current investigation utilized next-generation RNAseq technology to reveal that biotype 2 over expresses proteins involved in calcium signaling, which activates phosphoinositide (PI) metabolism. Calcium signaling proteins comprised 36% of all transcripts identified in the two D. noxia biotypes. Depending on plant resistance gene-aphid biotype interaction, additional transcript groups included those involved in tissue growth; defense and stress response; zinc ion and related cofactor binding; and apoptosis. Activation of enzymes involved in PI metabolism by D. noxia biotype 2 aphids allows depletion of plant calcium that normally blocks aphid feeding sites in phloem sieve elements and enables successful, continuous feeding on plants resistant to avirulent biotype 1. Inhibition of the key enzyme phospholipase C significantly reduced biotype 2 salivation into phloem and phloem sap ingestion.

  18. Metabolism of β-amyloid precursor protein, expressions of its related enzymes and effect of pioglitazone intervention in the brain of insulin resistance rats%胰岛素抵抗大鼠脑组织APP代谢及其相关酶的表达及吡格列酮的干预效果

    Institute of Scientific and Technical Information of China (English)

    袁树华; 高顺宗; 刘雪平; 郝跃伟; 赵婷婷; 侯亮

    2009-01-01

    目的 观察胰岛素抵抗(IR)大鼠脑组织β-淀粉样蛋白(Aβ)、淀粉样前体蛋白(APP)及其代谢相关酶的表达及吡格列酮(PIO)的干预效果.方法从45只Wistar大鼠中随机选取10只作为对照组(NC组),35只给予10%果糖水诱发胰岛素抵抗,4周后根据胰岛素抵抗指数(IRI),将制作成功的胰岛素抵抗模型26只大鼠随机分为IR组、PIO组.PIO组灌服吡格列酮(10 mg·kg~(-1)·d~(-1))12周,IR组和NC组给予相同体积的生理盐水.免疫组化法观察大鼠海马Aβ42的表达;免疫印迹法检测大鼠脑APP、β-分泌酶(BACE1)、γ-分泌酶(PSI)的变化.结果IR组和PIO组大鼠海马Aβ42的表达明显高于NC组,与IR组相比,PIO组表达明显减低(P<0.01);与NC组相比,IR组和PIO组大鼠脑组织APP、BACE1及PS1的表达增高,PIO组表达较IR组减少(P<0.05).结论胰岛素抵抗大鼠脑组织通过上调BACE1、PS1活性,使Aβ42生成增加;吡格列酮能抑制BACE1、PS1的表达,减少Aβ42生成.%Objective To investigate the expressions of β-amyloid (Aβ), amyloid precmsor protein (APP) and its metabohsm-related enzymes, and to explore the effect of pioglitazone (PIO) intervention in the brain of insulin resistance rats. Methods Of 45 Wistar male rats, 10 were randomly chosen as the control group (NC group), and the others were given 10% fructose for 4 weeks to develop the insulin resistance (IR) model. 26 IR rats were randomly divided into the IR group(n = 13) and the PIO group (n= 13). The PIO group was given pioglitazone(10 mg·kg~(-1)·d~(-1) by gavage for 12 weeks, and the IR and NC groups were given an identical volume of physiological saline. Immunohistochemistry and Western blotting were employed to examine the level of Aβ42 in the hippoeampus and the changes of APP, β-secretase (BACE1) and γ-secretase (PSI) in the brain tissue, Re-suits Immunohistoehemistry results indicated that the optical density of Aβ42 in the hippocampus of the IR and PIO groups was

  19. Protein adsorption resistance of PVP-modified polyurethane film prepared by surface-initiated atom transfer radical polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Huihui; Qian, Bin; Zhang, Wei [Shanghai Key Laboratory of Functional Materials Chemistry and Research Center of Analysis and Test, East China University of Science and Technology, Shanghai 200237 (China); Lan, Minbo, E-mail: minbolan@ecust.edu.cn [Shanghai Key Laboratory of Functional Materials Chemistry and Research Center of Analysis and Test, East China University of Science and Technology, Shanghai 200237 (China); State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237 (China)

    2016-02-15

    Highlights: • Antifouling PVP brushes were successfully grafted on PU films by SI-ATRP. • The effect of polymerization time on surface property and topography was studied. • Hydrophilicity and protein fouling resistance of PVP–PU films were greatly promoted. • Competitive adsorption of three proteins on PVP–PU films was evaluated. - Abstract: An anti-fouling surface of polyurethane (PU) film grafted with Poly(N-vinylpyrrolidone) (PVP) was prepared through surface-initiated atom transfer radical polymerization (SI-ATRP). And the polymerization time was investigated to obtain PU films with PVP brushes of different lengths. The surface properties and protein adsorption of modified PU films were evaluated. The results showed that the hydrophilicity of PU–PVP films were improved with the increase of polymerization time, which was not positive correlation with the surface roughness due to the brush structure. Additionally, the protein resistance performance was promoted when prolonging the polymerization time. The best antifouling PU–PVP (6.0 h) film reduced the adsoption level of bovine serum albumin (BSA), lysozyme (LYS), and brovin serum fibrinogen (BFG) by 93.4%, 68.3%, 85.6%, respectively, compared to the unmodified PU film. The competitive adsorption of three proteins indicated that LYS preferentially adsorbed on the modified PU film, while BFG had the lowest adsorption selectivity. And the amount of BFG on PU–PVP (6.0 h) film reduced greatly to 0.08 μg/cm{sup 2}, which was almost one-tenth of its adsorption from the single-protein system. Presented results suggested that both hydrophilicity and surface roughness might be the important factors in all cases of protein adsorption, and the competitive or selective adsorption might be related to the size of the proteins, especially on the non-charged films.

  20. Vinblastine and sulfinpyrazone export by the multidrug resistance protein MRP2 is associated with glutathione export

    OpenAIRE

    Evers, R.; Haas, M; Sparidans, R; Beijnen, J.; Wielinga, P R; Lankelma, J.; Borst, P

    2000-01-01

    The multidrug resistance proteins MRP1 and MRP2 are members of the same subfamily of ATP-binding cassette transporters. Besides organic molecules conjugated to negatively charged ligands, these proteins also transport cytotoxic drugs for which no negatively charged conjugates are known to exist. In polarized MDCKII cells, MRP1 routes to the lateral plasma membrane, and MRP2 to the apical plasma membrane. In these cells MRP1 transports daunorubicin, and MRP2 vinblastine; both transporters expo...

  1. Dual mode of action of Bt proteins: protoxin efficacy against resistant insects

    OpenAIRE

    2015-01-01

    Transgenic crops that produce Bacillus thuringiensis (Bt) proteins for pest control are grown extensively, but insect adaptation can reduce their effectiveness. Established mode of action models assert that Bt proteins Cry1Ab and Cry1Ac are produced as inactive protoxins that require conversion to a smaller activated form to exert toxicity. However, contrary to this widely accepted paradigm, we report evidence from seven resistant strains of three major crop pests showing that Cry1Ab and Cry1...

  2. Acute Inflammatory Response to Low-, Moderate-, and High-Load Resistance Exercise in Women With Breast Cancer-Related Lymphedema.

    Science.gov (United States)

    Cormie, Prue; Singh, Benjamin; Hayes, Sandi; Peake, Jonathan M; Galvão, Daniel A; Taaffe, Dennis R; Spry, Nigel; Nosaka, Kazunori; Cornish, Bruce; Schmitz, Kathryn H; Newton, Robert U

    2016-09-01

    Background Resistance exercise is emerging as a potential adjunct therapy to aid in the management of breast cancer-related lymphedema (BCRL). However, the mechanisms underlying the relationships between the acute and long-term benefits of resistance exercise on BCRL are not well understood. Purpose To examine the acute inflammatory response to upper-body resistance exercise in women with BCRL and to compare these effects between resistance exercises involving low, moderate, and high loads. The impact on lymphedema status and associated symptoms was also compared. Methods A total of 21 women, 62 ± 10 years old, with BCRL participated in the study. Participants completed low-load (15-20 repetition maximum [RM]), moderate-load (10-12 RM), and high-load (6-8 RM) exercise sessions consisting of 3 sets of 6 upper-body resistance exercises. Sessions were completed in a randomized order separated by a 7- to 10-day wash-out period. Venous blood samples were obtained to assess markers of exercise-induced muscle damage and inflammation. Lymphedema status was assessed using bioimpedance spectroscopy and arm circumferences, and associated symptoms were assessed using Visual Analogue Scales for pain, heaviness, and tightness. Measurements were conducted before and 24 hours after the exercise sessions. Results No significant changes in creatine kinase, C-reactive protein, interleukin-6, and tumor necrosis factor-α were observed following the 3 resistance exercise sessions. There were no significant changes in arm swelling or symptom severity scores across the 3 resistance exercise conditions. Conclusions The magnitude of acute exercise-induced inflammation following upper-body resistance exercise in women with BCRL does not vary between resistance exercise loads. © The Author(s) 2015.

  3. Iron Regulatory Proteins Mediate Host Resistance to Salmonella Infection.

    Science.gov (United States)

    Nairz, Manfred; Ferring-Appel, Dunja; Casarrubea, Daniela; Sonnweber, Thomas; Viatte, Lydie; Schroll, Andrea; Haschka, David; Fang, Ferric C; Hentze, Matthias W; Weiss, Guenter; Galy, Bruno

    2015-08-12

    Macrophages are essential for systemic iron recycling, and also control iron availability to pathogens. Iron metabolism in mammalian cells is orchestrated posttranscriptionally by iron-regulatory proteins (IRP)-1 and -2. Here, we generated mice with selective and combined ablation of both IRPs in macrophages to investigate the role of IRPs in controlling iron availability. These animals are hyperferritinemic but otherwise display normal clinical iron parameters. However, mutant mice rapidly succumb to systemic infection with Salmonella Typhimurium, a pathogenic bacterium that multiplies within macrophages, with increased bacterial burdens in liver and spleen. Ex vivo infection experiments indicate that IRP function restricts bacterial access to iron via the EntC and Feo bacterial iron-acquisition systems. Further, IRPs contain Salmonella by promoting the induction of lipocalin 2, a host antimicrobial factor that inhibits bacterial uptake of iron-laden siderophores, and by suppressing the ferritin iron pool. This work reveals the importance of the IRPs in innate immunity.

  4. Patterns of molecular evolution in pathogenesis-related proteins

    OpenAIRE

    Scherer,Nicole M.; Thompson,Claudia E.; Freitas,Loreta B.; Bonatto, Sandro L.; Salzano,Francisco M.

    2005-01-01

    The genes encoding 13 classes of pathogenesis-related (PR) proteins were examined for positive selection using maximum-likelihood (ML) models of codon substitution. The study involved 194 sequences from 54 species belonging to 37 genera. Although the sizes of the sequences examined varied from 237 bp for PR12 to 1,110 bp for PR7, most classes (9 out of 13) contained sequences made up of more than 400 nucleotides. Signs of positive selection were obtained for sites in PR proteins 4, 6, 8, 9 an...

  5. Serum Profiling Using Protein Microarrays to Identify Disease Related Antigens

    OpenAIRE

    2014-01-01

    Disease related antigens are of great importance in the clinic. They are used as markers to screen patients for various forms of cancer, to monitor response to therapy, or to serve as therapeutic targets (Chapman et al., Ann Oncol 18(5):868–873, 2007; Soussi et al., Cancer Res 60:1777–1788, 2000; Anderson and LaBaer, J Proteome Res 4:1123–1133, 2005; Levenson, Biochim Biophy Acta 1770:847–856, 2007). In cancer endogenous levels of protein expression may be disrupted or proteins may be express...

  6. Amylin evokes protein p20 phosphorylation and insulin resistance in rat skeletal muscle extensor digitorum longus

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In the present study, we investigate effect of amylin on the insulin sensitivity of rat skeletal muscle extensor digitorum longus (EDL) using in vitro intact muscle incubation in combination with metabolic radioactive labeling. The molecular basis of the amylin action was further examined using proteomic analysis. In particular, proteins of interest were characterized using an integrated microcharacterization procedure that involved in-gel trypsin digestion, organic solvent extraction, high performance liquid chromatography separation, microsequencing and microsequence analysis. We found that amylin significantly decreased the insulin-stimulated glucose incorporation into glycogen (p < 0.01) and produced a protein spot of approximately 20 ku in size. This amylin responsive protein (hereby designated as amylin responsive protein 1, APR1) was identified to be protein p20. Moreover, ARP1 spots on gels were found to consistently produce a corresponding radioactive spot on X-ray films in 32Pi but not in 35S-methionine labeling experiments. In conclusion, our results showed that in vitro amylin concomitantly evoked the production of ARP1 and caused insulin resistance in EDL muscle. It is suggested that protein p20 may be involved in amylin signal transduction and the appearance of ARP1 may be a step in a molecular pathway leading to the development of insulin resistance. ARP1 might therefore be a useful molecular marker for amylin action, insulin resistance and Type 2 diabetes.

  7. Ubiquitination-mediated degradation of cell cycle-related proteins by F-box proteins.

    Science.gov (United States)

    Zheng, Nana; Wang, Zhiwei; Wei, Wenyi

    2016-04-01

    F-box proteins, subunits of SKP1-cullin 1-F-box protein (SCF) type of E3 ubiquitin ligase complexes, have been validated to play a crucial role in governing various cellular processes such as cell cycle, cell proliferation, apoptosis, migration, invasion and metastasis. Recently, a wealth of evidence has emerged that F-box proteins is critically involved in tumorigenesis in part through governing the ubiquitination and subsequent degradation of cell cycle proteins, and dysregulation of this process leads to aberrant cell cycle progression and ultimately, tumorigenesis. Therefore, in this review, we describe the critical role of F-box proteins in the timely regulation of cell cycle. Moreover, we discuss how F-box proteins involve in tumorigenesis via targeting cell cycle-related proteins using biochemistry studies, engineered mouse models, and pathological gene alternations. We conclude that inhibitors of F-box proteins could have promising therapeutic potentials in part through controlling of aberrant cell cycle progression for cancer therapies.

  8. Multidrug resistance protein 1 localization in lipid raft domains and prostasomes in prostate cancer cell lines

    Directory of Open Access Journals (Sweden)

    Gomà A

    2014-12-01

    Full Text Available Alba Gomà,1,* Roser Mir,1–3,* Fina Martínez-Soler,1,4 Avelina Tortosa,4 August Vidal,5,6 Enric Condom,5,6 Ricardo Pérez–Tomás,6 Pepita Giménez-Bonafé1 1Departament de Ciències Fisiològiques II, Faculty of Medicine, Campus of Health Sciences of Bellvitge, Universitat de Barcelona, IDIBELL, Barcelona, Spain; 2División de Investigación Básica, Instituto Nacional de Cancerología, México DF, Mexico; 3Instituto de Física, Universidad Nacional Autónoma de México (UNAM, México DF, Mexico; 4Department of Basic Nursing, School of Nursing of the Health Campus of Bellvitge, Universitat de Barcelona, 5Department of Pathology, Hospital Universitari de Bellvitge, 6Department of Pathology and Experimental Therapeutics, Universitat de Barcelona, IDIBELL, Barcelona, Spain*These authors contributed equally to this work Background: One of the problems in prostate cancer (CaP treatment is the appearance of the multidrug resistance phenotype, in which ATP-binding cassette transporters such as multidrug resistance protein 1 (MRP1 play a role. Different localizations of the transporter have been reported, some of them related to the chemoresistant phenotype.Aim: This study aimed to compare the localization of MRP1 in three prostate cell lines (normal, androgen-sensitive, and androgen-independent in order to understand its possible role in CaP chemoresistance.Methods: MRP1 and caveolae protein markers were detected using confocal microscopy, performing colocalization techniques. Lipid raft isolation made it possible to detect these proteins by Western blot analysis. Caveolae and prostasomes were identified by electron microscopy.Results: We show that MRP1 is found in lipid raft fractions of tumor cells and that the number of caveolae increases with malignancy acquisition. MRP1 is found not only in the plasma membrane associated with lipid rafts but also in cytoplasmic accumulations colocalizing with the prostasome markers Caveolin-1 and CD59

  9. Intestinal Ciprofloxacin Efflux: The Role of Breast Cancer Resistance Protein (ABCG2)

    Science.gov (United States)

    Wright, J. A.; O'Reilly, D. A.; Sherlock, D. J.; Coleman, T.; Simmons, N. L.

    2011-01-01

    Intestinal secretory movement of the fluoroquinolone antibiotic, ciprofloxacin, may limit its oral bioavailability. Active ATP-binding cassette (ABC) transporters such as breast cancer resistance protein (BCRP) have been implicated in ciprofloxacin transport. The aim of this study was to test the hypothesis that BCRP alone mediates intestinal ciprofloxacin secretion. The involvement of ABC transport proteins in ciprofloxacin secretory flux was investigated with the combined use of transfected cell lines [bcrp1/BCRP-Madin-Darby canine kidney II (MDCKII) and multidrug resistance-related protein 4 (MRP4)-human embryonic kidney (HEK) 293] and human intestinal Caco-2 cells, combined with pharmacological inhibition using 3-(6-isobutyl-9-methoxy-1,4-dioxo-1,2,3,4,6, 7,12,12a-octahydropyrazino[1′,2′:1,6]pyrido[3,4-b]indol-3-yl)-propionic acid tert-butyl ester (Ko143), cyclosporine, 3-[[3-[2-(7-chloroquinolin-2-yl)vinyl]phenyl]-(2-dimethylcarbamoylethylsulfanyl)methylsulfanyl] propionic acid (MK571), and verapamil as ABC-selective inhibitors. In addition, the regional variation in secretory capacity was investigated using male Han Wistar rat intestine mounted in Ussing chambers, and the first indicative measurements of ciprofloxacin transport by ex vivo human jejunum were made. Active, Ko143-sensitive ciprofloxacin secretion was observed in bcrp1-MDCKII cell layers, but in low-passage (BCRP-expressing) Caco-2 cell layers only a 54% fraction was Ko143-sensitive. Ciprofloxacin accumulation was lower in MRP4-HEK293 cells than in the parent line, indicating that ciprofloxacin is also a substrate for this transporter. Ciprofloxacin secretion by Caco-2 cell layers was not inhibited by MK571. Secretory flux showed marked regional variability in the rat intestine, increasing from the duodenum to peak in the ileum. Ciprofloxacin secretion was present in human jejunum and was reduced by Ko143 but showed marked interindividual variability. Ciprofloxacin is a substrate for human

  10. L-Alanylglutamine inhibits signaling proteins that activate protein degradation, but does not affect proteins that activate protein synthesis after an acute resistance exercise.

    Science.gov (United States)

    Wang, Wanyi; Choi, Ran Hee; Solares, Geoffrey J; Tseng, Hung-Min; Ding, Zhenping; Kim, Kyoungrae; Ivy, John L

    2015-07-01

    Sustamine™ (SUS) is a dipeptide composed of alanine and glutamine (AlaGln). Glutamine has been suggested to increase muscle protein accretion; however, the underlying molecular mechanisms of glutamine on muscle protein metabolism following resistance exercise have not been fully addressed. In the present study, 2-month-old rats climbed a ladder 10 times with a weight equal to 75 % of their body mass attached at the tail. Rats were then orally administered one of four solutions: placebo (PLA-glycine = 0.52 g/kg), whey protein (WP = 0.4 g/kg), low dose of SUS (LSUS = 0.1 g/kg), or high dose of SUS (HSUS = 0.5 g/kg). An additional group of sedentary (SED) rats was intubated with glycine (0.52 g/kg) at the same time as the ladder-climbing rats. Blood samples were collected immediately after exercise and at either 20 or 40 min after recovery. The flexor hallucis longus (FHL), a muscle used for climbing, was excised at 20 or 40 min post exercise and analyzed for proteins regulating protein synthesis and degradation. All supplements elevated the phosphorylation of FOXO3A above SED at 20 min post exercise, but only the SUS supplements significantly reduced the phosphorylation of AMPK and NF-kB p65. SUS supplements had no effect on mTOR signaling, but WP supplementation yielded a greater phosphorylation of mTOR, p70S6k, and rpS6 compared with PLA at 20 min post exercise. However, by 40 min post exercise, phosphorylation of mTOR and rpS6 in PLA had risen to levels not different than WP. These results suggest that SUS blocks the activation of intracellular signals for MPB, whereas WP accelerates mRNA translation.

  11. The heat-shock protein/chaperone network and multiple stress resistance.

    Science.gov (United States)

    Jacob, Pierre; Hirt, Heribert; Bendahmane, Abdelhafid

    2017-04-01

    Crop yield has been greatly enhanced during the last century. However, most elite cultivars are adapted to temperate climates and are not well suited to more stressful conditions. In the context of climate change, stress resistance is a major concern. To overcome these difficulties, scientists may help breeders by providing genetic markers associated with stress resistance. However, multistress resistance cannot be obtained from the simple addition of single stress resistance traits. In the field, stresses are unpredictable and several may occur at once. Consequently, the use of single stress resistance traits is often inadequate. Although it has been historically linked with the heat stress response, the heat-shock protein (HSP)/chaperone network is a major component of multiple stress responses. Among the HSP/chaperone 'client proteins', many are primary metabolism enzymes and signal transduction components with essential roles for the proper functioning of a cell. HSPs/chaperones are controlled by the action of diverse heat-shock factors, which are recruited under stress conditions. In this review, we give an overview of the regulation of the HSP/chaperone network with a focus on Arabidopsis thaliana. We illustrate the role of HSPs/chaperones in regulating diverse signalling pathways and discuss several basic principles that should be considered for engineering multiple stress resistance in crops through the HSP/chaperone network. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  12. Novel mechanism of bacteriocin secretion and immunity carried out by lactococcal multidrug resistance proteins

    NARCIS (Netherlands)

    Gajic, O; Buist, G; Kojic, M; Topisirovic, L; Kuipers, OP; Kok, J

    2003-01-01

    A natural isolate of Lactococcus lactis was shown to produce two narrow spectrum class II bacteriocins, designated LsbA and LsbB. The cognate genes are located on a 5.6-kb plasmid within a gene cluster specifying LmrB, an ATP-binding cassette-type multidrug resistance transporter protein. LsbA is a

  13. Novel mechanism of bacteriocin secretion and immunity carried out by lactococcal multidrug resistance proteins

    NARCIS (Netherlands)

    Gajic, O; Buist, G; Kojic, M; Topisirovic, L; Kuipers, OP; Kok, J

    2003-01-01

    A natural isolate of Lactococcus lactis was shown to produce two narrow spectrum class II bacteriocins, designated LsbA and LsbB. The cognate genes are located on a 5.6-kb plasmid within a gene cluster specifying LmrB, an ATP-binding cassette-type multidrug resistance transporter protein. LsbA is a

  14. Expression of multidrug resistance-associated proteins predicts prognosis in childhood and adult acute lymphoblastic leukemia

    NARCIS (Netherlands)

    Plasschaert, SLA; de Bont, ESJM; Boezen, M; vander Kolk, DM; Daenen, SMJG; Faber, KN; Kamps, WA; de Vries, EGE; Vellenga, E

    2005-01-01

    PURPOSE: Patients with acute lymphoblastic leukemia (ALL) are treated with a variety of chemotherapeutic drugs, which can be transported by six multidrug resistance-associated proteins (MRP). These MRPs have strongly overlapping functional activities. The aim of this study was to investigate the exp

  15. Association of ERCC1 protein expression to platinum resistance in epithelial ovarian cancer

    DEFF Research Database (Denmark)

    Dahl Steffensen, Karina; Waldstrøm, Marianne; Jakobsen, Anders

    was to investigate if immunohistochemical expression of ERCC1 protein was associated with resistance to standard combination carboplatin and paclitaxel chemotherapy in newly diagnosed ovarian cancer patients. Methods: Formalin-fixed, paraffin-embedded tissue sections from 101 patients with newly diagnosed ovarian...

  16. Crystal Structures of Penicillin-Binding Protein 2 From Penicillin-Susceptible And -Resistant Strains of Neisseria Gonorrhoeae Reveal An Unexpectedly Subtle Mechanism for Antibiotic Resistance

    Energy Technology Data Exchange (ETDEWEB)

    Powell, A.J.; Tomberg, J.; Deacon, A.M.; Nicholas, R.A.; Davies, C.

    2009-05-21

    Penicillin-binding protein 2 (PBP2) from N. gonorrhoeae is the major molecular target for {beta}-lactam antibiotics used to treat gonococcal infections. PBP2 from penicillin-resistant strains of N. gonorrhoeae harbors an aspartate insertion after position 345 (Asp-345a) and 4-8 additional mutations, but how these alter the architecture of the protein is unknown. We have determined the crystal structure of PBP2 derived from the penicillin-susceptible strain FA19, which shows that the likely effect of Asp-345a is to alter a hydrogen-bonding network involving Asp-346 and the SXN triad at the active site. We have also solved the crystal structure of PBP2 derived from the penicillin-resistant strain FA6140 that contains four mutations near the C terminus of the protein. Although these mutations lower the second order rate of acylation for penicillin by 5-fold relative to wild type, comparison of the two structures shows only minor structural differences, with the positions of the conserved residues in the active site essentially the same in both. Kinetic analyses indicate that two mutations, P551S and F504L, are mainly responsible for the decrease in acylation rate. Melting curves show that the four mutations lower the thermal stability of the enzyme. Overall, these data suggest that the molecular mechanism underlying antibiotic resistance contributed by the four mutations is subtle and involves a small but measurable disordering of residues in the active site region that either restricts the binding of antibiotic or impedes conformational changes that are required for acylation by {beta}-lactam antibiotics.

  17. Transgenic maize plants expressing the Totivirus antifungal protein, KP4, are highly resistant to corn smut.

    Science.gov (United States)

    Allen, Aron; Islamovic, Emir; Kaur, Jagdeep; Gold, Scott; Shah, Dilip; Smith, Thomas J

    2011-10-01

    The corn smut fungus, Ustilago maydis, is a global pathogen responsible for extensive agricultural losses. Control of corn smut using traditional breeding has met with limited success because natural resistance to U. maydis is organ specific and involves numerous maize genes. Here, we present a transgenic approach by constitutively expressing the Totivirus antifungal protein KP4, in maize. Transgenic maize plants expressed high levels of KP4 with no apparent negative impact on plant development and displayed robust resistance to U. maydis challenges to both the stem and ear tissues in the greenhouse. More broadly, these results demonstrate that a high level of organ independent fungal resistance can be afforded by transgenic expression of this family of antifungal proteins.

  18. Dual mode of action of Bt proteins: protoxin efficacy against resistant insects.

    Science.gov (United States)

    Tabashnik, Bruce E; Zhang, Min; Fabrick, Jeffrey A; Wu, Yidong; Gao, Meijing; Huang, Fangneng; Wei, Jizhen; Zhang, Jie; Yelich, Alexander; Unnithan, Gopalan C; Bravo, Alejandra; Soberón, Mario; Carrière, Yves; Li, Xianchun

    2015-10-12

    Transgenic crops that produce Bacillus thuringiensis (Bt) proteins for pest control are grown extensively, but insect adaptation can reduce their effectiveness. Established mode of action models assert that Bt proteins Cry1Ab and Cry1Ac are produced as inactive protoxins that require conversion to a smaller activated form to exert toxicity. However, contrary to this widely accepted paradigm, we report evidence from seven resistant strains of three major crop pests showing that Cry1Ab and Cry1Ac protoxins were generally more potent than the corresponding activated toxins. Moreover, resistance was higher to activated toxins than protoxins in eight of nine cases evaluated in this study. These data and previously reported results support a new model in which protoxins and activated toxins kill insects via different pathways. Recognizing that protoxins can be more potent than activated toxins against resistant insects may help to enhance and sustain the efficacy of transgenic Bt crops.

  19. Nanoparticles in relation to peptide and protein aggregation

    Science.gov (United States)

    Zaman, Masihuz; Ahmad, Ejaz; Qadeer, Atiyatul; Rabbani, Gulam; Khan, Rizwan Hasan

    2014-01-01

    Over the past two decades, there has been considerable research interest in the use of nanoparticles in the study of protein and peptide aggregation, and of amyloid-related diseases. The influence of nanoparticles on amyloid formation yields great interest due to its small size and high surface area-to-volume ratio. Targeting nucleation kinetics by nanoparticles is one of the most searched for ways to control or induce this phenomenon. The observed effect of nanoparticles on the nucleation phase is determined by particle composition, as well as the amount and nature of the particle’s surface. Various thermodynamic parameters influence the interaction of proteins and nanoparticles in the solution, and regulate the protein assembly into fibrils, as well as the disaggregation of preformed fibrils. Metals, organic particles, inorganic particles, amino acids, peptides, proteins, and so on are more suitable candidates for nanoparticle formulation. In the present review, we attempt to explore the effects of nanoparticles on protein and peptide fibrillation processes from both perspectives (ie, as inducers and inhibitors on nucleation kinetics and in the disaggregation of preformed fibrils). Their formulation and characterization by different techniques have been also addressed, along with their toxicological effects, both in vivo and in vitro. PMID:24611007

  20. Aspirin resistance and other aspirin-related concerns.

    Science.gov (United States)

    Cai, Gaoyu; Zhou, Weijun; Lu, Ya; Chen, Peili; Lu, Zhongjiao; Fu, Yi

    2016-02-01

    Aspirin is a widely used medication and has become a cornerstone for treating cardiovascular disease. Aspirin can significantly reduce the incidence of cardiovascular ischemic events, recurrence and mortality, thereby improving the long-term prognosis of patients. However, there has been a staggering increase in the volume of literature addressing the issue of so-called "aspirin resistance" in recent years, and for some patients, it is difficult to avoid adverse reactions to aspirin. In this review, we present both the historical aspects of aspirin use and contemporary developments in its clinical use.

  1. Leptin Resistance: A Possible Interface Between Obesity and Pulmonary-Related Disorders

    Directory of Open Access Journals (Sweden)

    Rehman Khan

    2016-02-01

    Full Text Available Context Under normal physiological conditions, leptin regulates body weight by creating a balance between food intake and energy expenditure. However, in obesity, serum leptin levels increase and become defective to retain energy balance. Evidence Acquisition Elevated serum leptin levels are regarded as an established marker of obesity. It is also reported that obese asthmatic patients have maximum serum leptin levels compared to other groups such as non-obese asthmatics, and normal obese and non obese subjects without asthma. In addition to having an appetite suppressing effect, leptin also regulates certain acute-phase protein expressions including α-1 antitrypsin (A1AT in the liver. Results A1AT is a protease inhibitor that counterbalances the activity of the neutrophil elastase (NE enzyme. A1AT reductions in obese-leptin resistant subjects lead to increased NE activity. The overactivity of NE degrades lung tissue proteins, which may lead to pulmonary disorders including asthma. Conclusions On the basis of prior studies, it could be hypothesized that, in obese asthmatic patients, the highest degree of leptin failure/resistance might lead to the creation of an imbalance between NE and its inhibitor A1AT. To ascertain this, large scale prospective studies are warranted to assess the comparative serum leptin and A1AT levels and NE activity in asthmatic non-obese and obese patients, simultaneously. Such studies might help to devise novel interventional therapies for the treatment of pulmonary-related problems including asthma, chronic obstructive pulmonary disorder (COPD, and other lung defects in susceptible obese subjects in the future.

  2. Hypoxia-inducible factor-1α induces multidrug resistance protein in colon cancer

    Directory of Open Access Journals (Sweden)

    Lv Y

    2015-07-01

    Full Text Available Yingqian Lv, Shan Zhao, Jinzhu Han, Likang Zheng, Zixin Yang, Li Zhao Department of Oncology, The Second Hospital, Hebei Medical University, Shijiazhuang, Hebei Province, People’s Republic of China Abstract: Multidrug resistance is the major cause of chemotherapy failure in many solid tumors, including colon cancer. Hypoxic environment is a feature for all solid tumors and is important for the development of tumor resistance to chemotherapy. Hypoxia-inducible factor (HIF-1α is the key transcription factor that mediates cellular response to hypoxia. HIF-1α has been shown to play an important role in tumor resistance; however, the mechanism is still not fully understood. Here, we found that HIF-1α and the drug resistance-associated gene multidrug resistance associated protein 1 (MRP1 were induced by treatment of colon cancer cells with the hypoxia-mimetic agent cobalt chloride. Inhibition of HIF-1α by RNA interference and dominant-negative protein can significantly reduce the induction of MRP1 by hypoxia. Bioinformatics analysis showed that a hypoxia response element is located at -378 to -373 bp upstream of the transcription start site of MRP1 gene. Luciferase reporter assay combined with mutation analysis confirmed that this element is essential for hypoxia-mediated activation of MRP gene. Furthermore, RNA interference revealed that HIF-1α is necessary for this hypoxia-driven activation of MRP1 promoter. Importantly, chromatin immunoprecipitation analysis demonstrated that HIF-1α could directly bind to this HRE site in vivo. Together, these data suggest that MRP1 is a downstream target gene of HIF-1α, which provides a potential novel mechanism for HIF-1α-mediated drug resistance in colon cancer and maybe other solid tumors as well. Keywords: hypoxia, hypoxia-inducible factor-1α, multidrug resistance associated protein, transcriptional regulation, chemotherapy tolerance

  3. Expression of Uncoupling Protein 2 in Breast Cancer Tissue and Drug-resistant Cells

    Institute of Scientific and Technical Information of China (English)

    Sun Yan; Yuan Yuan; Zhang Lili; Zhu Hong; Hu Sainan

    2013-01-01

    Objective:To explore the expression of uncoupling protein-2 (UCP2) in clinical breast cancer tissue and drug-resistant cells. Methods:The expression of UCP2 in breast cancer tissue and normal tissue adjacent to carcinoma as well as breast cancer cell MCF-7 and paclitaxel-resistant cell MX-1/T were respectively detected by immunohistochemistry and Western blot. Results:The expression of UCP2 in breast cancer tissue was signiifcantly higher than in normal tissue adjacent to carcinoma, and that in paclitaxel-resistant cell MX-1/T obviously higher than in breast cancer cell MCF-7. Conclusion:UCP2 is highly expressed in breast cancer tissue and drug-resistant cells.

  4. Transport of diclofenac by breast cancer resistance protein (ABCG2) and stimulation of multidrug resistance protein 2 (ABCC2)-mediated drug transport by diclofenac and benzbromarone.

    Science.gov (United States)

    Lagas, Jurjen S; van der Kruijssen, Cornelia M M; van de Wetering, Koen; Beijnen, Jos H; Schinkel, Alfred H

    2009-01-01

    Diclofenac is an important analgesic and anti-inflammatory drug, widely used for treatment of postoperative pain, rheumatoid arthritis, and chronic pain associated with cancer. Consequently, diclofenac is often used in combination regimens and undesirable drug-drug interactions may occur. Because many drug-drug interactions may occur at the level of drug transporting proteins, we studied interactions of diclofenac with apical ATP-binding cassette (ABC) multidrug efflux transporters. Using Madin-Darby canine kidney (MDCK)-II cells transfected with human P-glycoprotein (P-gp; MDR1/ABCB1), multidrug resistance protein 2 (MRP2/ABCC2), and breast cancer resistance protein (BCRP/ABCG2) and murine Bcrp1, we found that diclofenac was efficiently transported by murine Bcrp1 and moderately by human BCRP but not by P-gp or MRP2. Furthermore, in Sf9-BCRP membrane vesicles diclofenac inhibited transport of methotrexate in a concentration-dependent manner. We next used MDCK-II-MRP2 cells to study interactions of diclofenac with MRP2-mediated drug transport. Diclofenac stimulated paclitaxel, docetaxel, and saquinavir transport at only 50 microM. We further found that the uricosuric drug benzbromarone stimulated MRP2 at an even lower concentration, having maximal stimulatory activity at only 2 microM. Diclofenac and benzbromarone stimulated MRP2-mediated transport of amphipathic lipophilic drugs at 10- and 250-fold lower concentrations, respectively, than reported for other MRP2 stimulators. Because these concentrations are readily achieved in patients, adverse drug-drug interactions may occur, for example, during cancer therapy, in which drug concentrations are often critical and stimulation of elimination via MRP2 may result in suboptimal chemotherapeutic drug concentrations. Moreover, stimulation of MRP2 activity in tumors may lead to increased efflux of chemotherapeutic drugs and thereby drug resistance.

  5. Association among Fibrinolytic Proteins, Metabolic Syndrome Components, Insulin Secretion, and Resistance in Schoolchildren

    Directory of Open Access Journals (Sweden)

    Jin-Shuen Chen

    2015-01-01

    Full Text Available We investigated the role of urokinase plasminogen activator (uPA and its soluble receptors (suPAR and plasminogen activator inhibitor-1 (PAI-1 in metabolic syndrome (MetS components, insulin secretion, and resistance in schoolchildren. We enrolled 387 children, aged 10.3 ± 1.5 years, in Taipei. Anthropometry, fibrinolytic proteins, MetS components, insulin secretion, and resistance were measured. Subjects were divided into normal, overweight, and obese groups. Finally, the relationship between fibrinolytic proteins and metabolic syndrome in boys and girls was analyzed. In boys, PAI-1 was positively associated with body mass index (BMI percentile, hypertriglyceride, insulin secretion, and resistance. In girls, PAI-1 was positively associated with obesity, hypertriglyceridemia, and insulin secretion. In girls, uPA was positively associated with insulin secretion. suPAR was positively associated with high-sensitivity C-reactive protein in both boys and girls, and with BMI percentile and body fat in girls. The obese boys had higher suPAR and PAI-1 levels than the normal group. The obese girls had higher uPA, suPAR, and PAI-1 than the normal group. Boys and girls with MetS had higher PAI-1. Fibrinolytic proteins, especially PAI-1, are associated with MetS components and insulin secretion in children. Fibrinolytic proteins changes were more likely to occur in girls than in boys.

  6. Yersinia enterocolitica serum resistance proteins YadA and ail bind the complement regulator C4b-binding protein.

    Directory of Open Access Journals (Sweden)

    Vesa Kirjavainen

    Full Text Available Many pathogens are equipped with factors providing resistance against the bactericidal action of complement. Yersinia enterocolitica, a Gram-negative enteric pathogen with invasive properties, efficiently resists the deleterious action of human complement. The major Y. enterocolitica serum resistance determinants include outer membrane proteins YadA and Ail. Lipopolysaccharide (LPS O-antigen (O-ag and outer core (OC do not contribute directly to complement resistance. The aim of this study was to analyze a possible mechanism whereby Y. enterocolitica could inhibit the antibody-mediated classical pathway of complement activation. We show that Y. enterocolitica serotypes O:3, O:8, and O:9 bind C4b-binding protein (C4bp, an inhibitor of both the classical and lectin pathways of complement. To identify the C4bp receptors on Y. enterocolitica serotype O:3 surface, a set of mutants expressing YadA, Ail, O-ag, and OC in different combinations was tested for the ability to bind C4bp. The studies showed that both YadA and Ail acted as C4bp receptors. Ail-mediated C4bp binding, however, was blocked by the O-ag and OC, and could be observed only with mutants lacking these LPS structures. C4bp bound to Y. enterocolitica was functionally active and participated in the factor I-mediated degradation of C4b. These findings show that Y. enterocolitica uses two proteins, YadA and Ail, to bind C4bp. Binding of C4bp could help Y. enterocolitica to evade complement-mediated clearance in the human host.

  7. Structural basis of lantibiotic recognition by the nisin resistance protein from Streptococcus agalactiae.

    Science.gov (United States)

    Khosa, Sakshi; Frieg, Benedikt; Mulnaes, Daniel; Kleinschrodt, Diana; Hoeppner, Astrid; Gohlke, Holger; Smits, Sander H J

    2016-01-04

    Lantibiotics are potent antimicrobial peptides. Nisin is the most prominent member and contains five crucial lanthionine rings. Some clinically relevant bacteria express membrane-associated resistance proteins that proteolytically inactivate nisin. However, substrate recognition and specificity of these proteins is unknown. Here, we report the first three-dimensional structure of a nisin resistance protein from Streptococcus agalactiae (SaNSR) at 2.2 Å resolution. It contains an N-terminal helical bundle, and protease cap and core domains. The latter harbors the highly conserved TASSAEM region, which lies in a hydrophobic tunnel formed by all domains. By integrative modeling, mutagenesis studies, and genetic engineering of nisin variants, a model of the SaNSR/nisin complex is generated, revealing that SaNSR recognizes the last C-terminally located lanthionine ring of nisin. This determines the substrate specificity of SaNSR and ensures the exact coordination of the nisin cleavage site at the TASSAEM region.

  8. Structure of Deinococcus radiodurans tunicamycin-resistance protein (TmrD), a phosphotransferase

    Science.gov (United States)

    Kapp, Ulrike; Macedo, Sofia; Hall, David Richard; Leiros, Ingar; McSweeney, Sean M.; Mitchell, Edward

    2008-01-01

    The open-reading frame (ORF) DR_1419 in the Deinococcus radiodurans genome is annotated as a representative of the wide family of tunicamycin-resistance proteins as identified in a range of bacterial genomes. The D. radiodurans ORF DR_1419 was cloned and expressed; the protein TmrD was crystallized and its X-ray crystal structure was determined to 1.95 Å resolution. The structure was determined using single-wavelength anomalous diffraction with selenomethionine-derivatized protein. The refined structure is the first to be reported for a member of the tunicamycin-resistance family. It reveals strong structural similarity to the family of nucleoside monophosphate kinases and to the chloramphenicol phosphotransferase of Streptomyces venezuelae, suggesting that the mode of action is possibly by phosphorylation of tunicamycin. PMID:18540055

  9. Expression and activity of breast cancer resistance protein (BCRP) in de novo and relapsed acute myeloid leukemia

    NARCIS (Netherlands)

    Vellenga, E; Scheffer, GL; Muller, M; Bates, SE; Scheper, RJ; de Vries, EGE

    2002-01-01

    Overexpression of the breast cancer resistance protein (BCRP) efflux pump In human cancer cell lines results in resistance to a variety of cytostatic agents. The aim of this study was to analyze BCRP protein expression and activity In acute myeloid leukemia (AML) samples and to determine whether it

  10. Effect of Lanthanum on Disease Resistance Related Enzymes of Rape

    Institute of Scientific and Technical Information of China (English)

    曾青; 朱建国; 谢祖彬; 褚海燕; 张雅莉

    2003-01-01

    The effects of lanthanum on the protective enzymes of rape (Brassica juncea) were studied in hydroponics experiment. Results show that when treated with 0.3 mg*kg-1 La, the content of chlorophyll and the activities of peroxidase(POD), catalase(CAT), superoxide dismutase(SOD) and polyphenoloxidase(PPO) in rape increase, but the content of malondialdehyde(MDA) in rape decreases. However, the treatments do not change the content of soluble protein in rape significantly.

  11. Age-related differences in plasma proteins: how plasma proteins change from neonates to adults.

    Directory of Open Access Journals (Sweden)

    Vera Ignjatovic

    Full Text Available The incidence of major diseases such as cardiovascular disease, thrombosis and cancer increases with age and is the major cause of mortality world-wide, with neonates and children somehow protected from such diseases of ageing. We hypothesized that there are major developmental differences in plasma proteins and that these contribute to age-related changes in the incidence of major diseases. We evaluated the human plasma proteome in healthy neonates, children and adults using the 2D-DIGE approach. We demonstrate significant changes in number and abundance of up to 100 protein spots that have marked differences in during the transition of the plasma proteome from neonate and child through to adult. These proteins are known to be involved in numerous physiological processes such as iron transport and homeostasis, immune response, haemostasis and apoptosis, amongst others. Importantly, we determined that the proteins that are differentially expressed with age are not the same proteins that are differentially expressed with gender and that the degree of phosphorylation of plasma proteins also changes with age. Given the multi-functionality of these proteins in human physiology, understanding the differences in the plasma proteome in neonates and children compared to adults will make a major contribution to our understanding of developmental biology in humans.

  12. SCREENING OF DRUG RESISTANCE-RELATED GENES FROM HUMAN OVARIAN CANCER CELL LINE OC3/ADR BY DD-PCR

    Institute of Scientific and Technical Information of China (English)

    田方; 程国均; 周海胜; 王宏; 肖凤君

    2001-01-01

    Objective: To screen novel genes related to adriamycin (Adr) resistance from human ovarian cancer resistance cell line OC3/Adr. Methods: Multidrug resistant ovarian cancer cell line OC3/Adr was induced by intermittent treatment of the human parent cell line OC3 with high concentration Adr. The difference of gene expression was screened by using different display analysis to the acquired Adr-resistance subline OC3/Adr and its parent cell line OC3. Results: OC3/Adr cell line was obtained which was more resistance to Adr than the parent cell line OC3 with the resistance index (RI) of 15.4. The OC3/Adr cell line also showed cross-resistance to other anti-cancer drugs (VP16, CDDP,5FU ). It grew slowly and exhibited changes of cell cycle. A number of differentially expressed ESTs (Expressed Sequence Tags, ESTs) were identified at mRNA level between the OC3/Adr and OC3. Four of 18 different ESTs were sequenced. The 431/432 base pair S1 was homologous to human sperm zona pellucida binding protein, while the other two ESTs, S3 and S4, were new gene segments, which were registered to GenBank with the number of AF 117656 and AF 126507 respectively. Particularly, the expression of S2 sequence increased in all the drug-resistance cell lines and S3 sequence overexpressed in human ovarian cancer tissues as compared with benign ovarian tumors. Adr in ovarian cancer OC3/Adr is involved with changes of multiple gene expressions.

  13. WHEY PROTEIN-BASED WATER RESISTANT AND ENVIRONMENTALLY SAFE ADHESIVES FOR PLYWOOD

    Directory of Open Access Journals (Sweden)

    Zongyan Zhao

    2011-06-01

    Full Text Available Whey protein is a renewable and environmentally safe biomaterial, a by-product of cheese production. It can be utilized for non-food applications for value-added products. The substances glyoxal (GO, glutaraldehyde (GA, polymeric methylene biphenyl diisocyanate (p-MDI, urea-formaldehyde (UF resin, and phenol-formaldehyde oligomer (PFO that contain reactive groups were applied together with whey protein as modifier in order to increase crosslinking density and molecular weight for improving the bond strength and water resistance of whey protein. A water-resistant and environmentally safe whey protein-based wood adhesive for plywood was developed by evaluating the effects of these modifiers on the bond strength, bond durability, and free formaldehyde emission of the resulting plywood panels. Results of FTIR and SEM analyses and bond evaluation indicated that GO, GA, and p-MDI were not suitable to modify whey proteins due to their high reactivity with whey proteins, causing phase separation. UF resin was not a good modifier for whey proteins because of either its poor water-resistance or higher emission of hazardous formaldehyde. Whey protein adhesives modified with PFO had a dry shear bond strength of 1.98 MPa and a 28h-boiling-dry-boiling wet shear strength of 1.73 MPa, which were both much higher than the required values for structural use according to standard JIS K6806-2003, while its formaldehyde emission was 0.067mg/L, much lower than the required value for green plywood according to standard JIS A5908.

  14. Recombinant acylation stimulating protein administration to C3-/- mice increases insulin resistance via adipocyte inflammatory mechanisms.

    Directory of Open Access Journals (Sweden)

    Mercedes Nancy Munkonda

    Full Text Available BACKGROUND: Complement 3 (C3, a key component of the innate immune system, is involved in early inflammatory responses. Acylation stimulating protein (ASP; aka C3adesArg, a C3 cleavage product, is produced in adipose tissue and stimulates lipid storage. We hypothesized that, depending on the diet, chronic ASP administration in C3(-/- mice would affect lipid metabolism and insulin sensitivity via an adaptive adipose tissue inflammatory response. METHODOLOGY/PRINCIPAL FINDINGS: C3(-/- mice on normal low fat diet (ND or high fat diet (HFD were chronically administered recombinant ASP (rASP for 25 days via an osmotic mini-pump. While there was no effect on food intake, there was a decrease in activity, with a relative increase in adipose tissue weight on ND, and a shift in adipocyte size distribution. While rASP administration to C3(-/- mice on a ND increased insulin sensitivity, on a HFD, rASP administration had the opposite effect. Specifically, rASP administration in C3(-/- HFD mice resulted in decreased gene expression of IRS1, GLUT4, SREBF1 and NFκB in muscle, and decreased C5L2 but increased JNK, CD36, CD11c, CCR2 and NFκB gene expression in adipose tissue as well as increased secretion of proinflammatory cytokines (Rantes, KC, MCP-1, IL-6 and G-CSF. In adipose tissue, although IRS1 and GLUT4 mRNA were unchanged, insulin response was reduced. CONCLUSION: The effects of chronic rASP administration are tissue and diet specific, rASP administration enhances the HFD induced inflammatory response leading to an insulin-resistant state. These results suggest that, in humans, the increased plasma ASP associated with obesity and cardiovascular disease could be an additional factor directly contributing to development of metabolic syndrome, insulin resistance and diabetes.

  15. Jacalin domain in wheat jasmonate-regulated protein Ta-JA1 confers agglutinating activity and pathogen resistance.

    Science.gov (United States)

    Ma, Qing-Hu; Zhen, Wei-Bo; Liu, Yun-Chao

    2013-02-01

    Ta-JA1 is a jacalin-like lectin from wheat (Triticum aestivum) plants. To date, its homologs are only observed in the Gramineae family. Our previous experiments have demonstrated that Ta-JA1 contains a modular structure consisting of an N-terminal dirigent domain and a C-terminal jacalin-related lectin domain (JRL) and this protein exhibits a mannose-specific lectin activity. The over-expression of Ta-JA1 gene provides transgenic plants a broad-spectrum resistance to diseases. Here, we report the differential activities of the dirigent and JRL domains of Ta-JA1. In vitro assay showed that the recombinant JRL domain could effectively agglutinate rabbit erythrocytes and pathogen bacteria Pseudomonas syringe pv tabaci. These hemagglutination activities could be inhibited by mannose but not by galactose. In contrast, the recombinant dirigent domain did not show agglutination activity. Corresponding to these differentiations of activities, similar to full-length of Ta-JA1, the over-expression of JRL domain in transgenic plants also increased resistance to the infection of P. syringe. Unlike JRL, the over-expression of dirigent domain in transgenic plants led to alteration of the seedling sensitivity to salts. In addition, a d(N)/d(S) ratio analysis of Ta-JA1 and its related proteins showed that this protein family functionally limited to a few crop plants, such as maize, rice and wheat.

  16. Characterization of a Novel Endoplasmic Reticulum Protein Involved in Tubercidin Resistance in Leishmania major.

    Directory of Open Access Journals (Sweden)

    Juliana Ide Aoki

    2016-09-01

    Full Text Available Tubercidin (TUB is a toxic adenosine analog with potential antiparasitic activity against Leishmania, with mechanism of action and resistance that are not completely understood. For understanding the mechanisms of action and identifying the potential metabolic pathways affected by this drug, we employed in this study an overexpression/selection approach using TUB for the identification of potential targets, as well as, drug resistance genes in L. major. Although, TUB is toxic to the mammalian host, these findings can provide evidences for a rational drug design based on purine pathway against leishmaniasis.After transfection of a cosmid genomic library into L. major Friedlin (LmjF parasites and application of the overexpression/selection method, we identified two cosmids (cosTUB1 and cosTU2 containing two different loci capable of conferring significant levels of TUB resistance. In the cosTUB1 contained a gene encoding NUPM1-like protein, which has been previously described as associated with TUB resistance in L. amazonensis. In the cosTUB2 we identified and characterized a gene encoding a 63 kDa protein that we denoted as tubercidin-resistance protein (TRP. Functional analysis revealed that the transfectants were less susceptible to TUB than LmjF parasites or those transfected with the control vector. In addition, the trp mRNA and protein levels in cosTUB2 transfectants were higher than LmjF. TRP immunolocalization revealed that it was co-localized to the endoplasmic reticulum (ER, a cellular compartment with many functions. In silico predictions indicated that TRP contains only a hypothetical transmembrane domain. Thus, it is likely that TRP is a lumen protein involved in multidrug efflux transport that may be involved in the purine metabolic pathway.This study demonstrated for the first time that TRP is associated with TUB resistance in Leishmania. The next challenge is to determine how TRP mediates TUB resistance and whether purine

  17. Characterization of a Novel Endoplasmic Reticulum Protein Involved in Tubercidin Resistance in Leishmania major

    Science.gov (United States)

    Aoki, Juliana Ide; Coelho, Adriano Cappellazzo; Muxel, Sandra Marcia; Zampieri, Ricardo Andrade; Sanchez, Eduardo Milton Ramos; Nerland, Audun Helge; Floeter-Winter, Lucile Maria; Cotrim, Paulo Cesar

    2016-01-01

    Background Tubercidin (TUB) is a toxic adenosine analog with potential antiparasitic activity against Leishmania, with mechanism of action and resistance that are not completely understood. For understanding the mechanisms of action and identifying the potential metabolic pathways affected by this drug, we employed in this study an overexpression/selection approach using TUB for the identification of potential targets, as well as, drug resistance genes in L. major. Although, TUB is toxic to the mammalian host, these findings can provide evidences for a rational drug design based on purine pathway against leishmaniasis. Methodology/Principal findings After transfection of a cosmid genomic library into L. major Friedlin (LmjF) parasites and application of the overexpression/selection method, we identified two cosmids (cosTUB1 and cosTU2) containing two different loci capable of conferring significant levels of TUB resistance. In the cosTUB1 contained a gene encoding NUPM1-like protein, which has been previously described as associated with TUB resistance in L. amazonensis. In the cosTUB2 we identified and characterized a gene encoding a 63 kDa protein that we denoted as tubercidin-resistance protein (TRP). Functional analysis revealed that the transfectants were less susceptible to TUB than LmjF parasites or those transfected with the control vector. In addition, the trp mRNA and protein levels in cosTUB2 transfectants were higher than LmjF. TRP immunolocalization revealed that it was co-localized to the endoplasmic reticulum (ER), a cellular compartment with many functions. In silico predictions indicated that TRP contains only a hypothetical transmembrane domain. Thus, it is likely that TRP is a lumen protein involved in multidrug efflux transport that may be involved in the purine metabolic pathway. Conclusions/Significance This study demonstrated for the first time that TRP is associated with TUB resistance in Leishmania. The next challenge is to determine how

  18. An inhibitory interaction between viral and cellular proteins underlies the resistance of tomato to nonadapted tobamoviruses.

    Science.gov (United States)

    Ishibashi, Kazuhiro; Naito, Satoshi; Meshi, Tetsuo; Ishikawa, Masayuki

    2009-05-26

    Any individual virus can infect only a limited range of hosts, and most plant species are "nonhosts" to a given virus; i.e., all members of the species are insusceptible to the virus. In nonhost plants, the factors that control virus resistance are not genetically tractable, and how the host range of a virus is determined remains poorly understood. Tomato (Solanum lycopersicum) is a nonhost species for Tobacco mild green mosaic virus (TMGMV) and Pepper mild mottle virus (PMMoV), members of the genus Tobamovirus. Previously, we identified Tm-1, a resistance gene of tomato to another tobamovirus, Tomato mosaic virus (ToMV), and found that Tm-1 binds to ToMV replication proteins to inhibit RNA replication. Tm-1 is derived from a wild tomato species, S. habrochaites, and ToMV-susceptible tomato cultivars have the allelic gene tm-1. The tm-1 protein can neither bind to ToMV replication proteins nor inhibit ToMV multiplication. Here, we show that transgenic tobacco plants expressing tm-1 exhibit resistance to TMGMV and PMMoV. The tm-1 protein bound to the replication proteins of TMGMV and PMMoV and inhibited their RNA replication in vitro. In one of the tm-1-expressing tobacco plants, a tm-1-insensitive TMGMV mutant emerged. In tomato protoplasts, this mutant TMGMV multiplied as efficiently as ToMV. However, in tomato plants, the mutant TMGMV multiplied with lower efficiency compared to ToMV and caused systemic necrosis. These results suggest that an inhibitory interaction between the replication proteins and tm-1 underlies a multilayered resistance mechanism to TMGMV in tomato.

  19. Resistant starch and protein intake enhances fat oxidation and feelings of fullness in lean and overweight/obese women

    DEFF Research Database (Denmark)

    Gentile, Christopher L; Ward, Emery; Holst, Jens Juul

    2015-01-01

    BACKGROUND: Diets high in either resistant starch or protein have been shown to aid in weight management. We examined the effects of meals high in non-resistant or resistant starch with and without elevated protein intake on substrate utilization, energy expenditure, and satiety in lean...... and overweight/obese women. METHODS: Women of varying levels of adiposity consumed one of four pancake test meals in a single-blind, randomized crossover design: 1) waxy maize (control) starch (WMS); 2) waxy maize starch and whey protein (WMS+WP); 3) resistant starch (RS); or 4) RS and whey protein (RS...... factors were not different among any of the test meals. However, peptide YY (PYY) was significantly elevated at 180 min following RS+WP meal. CONCLUSIONS: The combined consumption of dietary resistant starch and protein increases fat oxidation, PYY, and enhances feelings of satiety and fullness to levels...

  20. Triclosan Resistance of Pseudomonas aeruginosa PAO1 Is Due to FabV, a Triclosan-Resistant Enoyl-Acyl Carrier Protein Reductase ▿

    OpenAIRE

    Zhu, Lei; Lin, Jinshui; Ma, Jincheng; Cronan, John E.; Wang, Haihong

    2009-01-01

    Triclosan, a very widely used biocide, specifically inhibits fatty acid synthesis by inhibition of enoyl-acyl carrier protein (ACP) reductase. Escherichia coli FabI is the prototypical triclosan-sensitive enoyl-ACP reductase, and E. coli is extremely sensitive to the biocide. However, other bacteria are resistant to triclosan, because they encode triclosan-resistant enoyl-ACP reductase isozymes. In contrast, the triclosan resistance of Pseudomonas aeruginosa PAO1 has been attributed to active...

  1. A relative resistance Ratio for Evaluation of Stem Borer Susceptibility Among Sugarcane Cultivars

    Science.gov (United States)

    The Mexican rice borer, Eoreuma loftini (Dyar), is a major pest of sugarcane in Louisiana and Texas. Cultivar resistance to E. loftini was evaluated in commercial and experimental sugarcane cultivars in four replicated field studies between 2009 and 2012. A relative resistance ratio was developed t...

  2. Partial stem and leaf resistance against the fungal pathogen Botrytis cinerea in wild relatives of tomato

    NARCIS (Netherlands)

    Have, ten A.; Berloo, van R.; Lindhout, P.; Kan, van J.A.L.

    2007-01-01

    Tomato (Solanum lycopersicum) is one of many greenhouse crops that can be infected by the necrotrophic ascomycete Botrytis cinerea. Commercial cultivation of tomato is hampered by the lack of resistance. Quantitative resistance has been reported in wild tomato relatives, mostly based on leaf assays.

  3. Amplification of a Gene Related to Mammalian mdr Genes in Drug-Resistant Plasmodium falciparum

    Science.gov (United States)

    Wilson, Craig M.; Serrano, Adelfa E.; Wasley, Annemarie; Bogenschutz, Michael P.; Shankar, Anuraj H.; Wirth, Dyann F.

    1989-06-01

    The malaria parasite Plasmodium falciparum contains at least two genes related to the mammalian multiple drug resistance genes, and at least one of the P. falciparum genes is expressed at a higher level and is present in higher copy number in a strain that is resistant to multiple drugs than in a strain that is sensitive to the drugs.

  4. Protein adsorption resistance of PVP-modified polyurethane film prepared by surface-initiated atom transfer radical polymerization

    Science.gov (United States)

    Yuan, Huihui; Qian, Bin; Zhang, Wei; Lan, Minbo

    2016-02-01

    An anti-fouling surface of polyurethane (PU) film grafted with Poly(N-vinylpyrrolidone) (PVP) was prepared through surface-initiated atom transfer radical polymerization (SI-ATRP). And the polymerization time was investigated to obtain PU films with PVP brushes of different lengths. The surface properties and protein adsorption of modified PU films were evaluated. The results showed that the hydrophilicity of PU-PVP films were improved with the increase of polymerization time, which was not positive correlation with the surface roughness due to the brush structure. Additionally, the protein resistance performance was promoted when prolonging the polymerization time. The best antifouling PU-PVP (6.0 h) film reduced the adsoption level of bovine serum albumin (BSA), lysozyme (LYS), and brovin serum fibrinogen (BFG) by 93.4%, 68.3%, 85.6%, respectively, compared to the unmodified PU film. The competitive adsorption of three proteins indicated that LYS preferentially adsorbed on the modified PU film, while BFG had the lowest adsorption selectivity. And the amount of BFG on PU-PVP (6.0 h) film reduced greatly to 0.08 μg/cm2, which was almost one-tenth of its adsorption from the single-protein system. Presented results suggested that both hydrophilicity and surface roughness might be the important factors in all cases of protein adsorption, and the competitive or selective adsorption might be related to the size of the proteins, especially on the non-charged films.

  5. JAM-related proteins in mucosal homeostasis and inflammation.

    Science.gov (United States)

    Luissint, Anny-Claude; Nusrat, Asma; Parkos, Charles A

    2014-03-01

    Mucosal surfaces are lined by epithelial cells that form a physical barrier protecting the body against external noxious substances and pathogens. At a molecular level, the mucosal barrier is regulated by tight junctions (TJs) that seal the paracellular space between adjacent epithelial cells. Transmembrane proteins within TJs include junctional adhesion molecules (JAMs) that belong to the cortical thymocyte marker for Xenopus family of proteins. JAM family encompasses three classical members (JAM-A, JAM-B, and JAM-C) and related molecules including JAM4, JAM-like protein, Coxsackie and adenovirus receptor (CAR), CAR-like membrane protein and endothelial cell-selective adhesion molecule. JAMs have multiple functions that include regulation of endothelial and epithelial paracellular permeability, leukocyte recruitment during inflammation, angiogenesis, cell migration, and proliferation. In this review, we summarize the current knowledge regarding the roles of the JAM family members in the regulation of mucosal homeostasis and leukocyte trafficking with a particular emphasis on barrier function and its perturbation during pathological inflammation.

  6. Resistance training with soy vs whey protein supplements in hyperlipidemic males

    Directory of Open Access Journals (Sweden)

    Leddy John J

    2009-03-01

    Full Text Available Abstract Background Most individuals at risk for developing cardiovascular disease (CVD can reduce risk factors through diet and exercise before resorting to drug treatment. The effect of a combination of resistance training with vegetable-based (soy versus animal-based (whey protein supplementation on CVD risk reduction has received little study. The study's purpose was to examine the effects of 12 weeks of resistance exercise training with soy versus whey protein supplementation on strength gains, body composition and serum lipid changes in overweight, hyperlipidemic men. Methods Twenty-eight overweight, male subjects (BMI 25–30 with serum cholesterol >200 mg/dl were randomly divided into 3 groups (placebo (n = 9, and soy (n = 9 or whey (n = 10 supplementation and participated in supervised resistance training for 12 weeks. Supplements were provided in a double blind fashion. Results All 3 groups had significant gains in strength, averaging 47% in all major muscle groups and significant increases in fat free mass (2.6%, with no difference among groups. Percent body fat and waist-to-hip ratio decreased significantly in all 3 groups an average of 8% and 2%, respectively, with no difference among groups. Total serum cholesterol decreased significantly, again with no difference among groups. Conclusion Participation in a 12 week resistance exercise training program significantly increased strength and improved both body composition and serum cholesterol in overweight, hypercholesterolemic men with no added benefit from protein supplementation.

  7. Exercise protects against diet-induced insulin resistance through downregulation of protein kinase Cβ in mice.

    Directory of Open Access Journals (Sweden)

    Xiaoquan Rao

    Full Text Available Physical exercise is an important and effective therapy for diabetes. However, its underlying mechanism is not fully understood. Protein kinase Cβ (PKCβ has been suggested to be involved in the pathogenesis of obesity and insulin resistance, but the role of PKCβ in exercise-induced improvements in insulin resistance is completely unknown. In this study, we evaluated the involvement of PKCβ in exercise-attenuated insulin resistance in high-fat diet (HFD-fed mice. PKCβ(-/- and wild-type mice were fed a HFD with or without exercise training. PKC protein expression, body and tissue weight change, glucose and insulin tolerance, metabolic rate, mitochondria size and number, adipose inflammation, and AKT activation were determined to evaluate insulin sensitivity and metabolic changes after intervention. PKCβ expression decreased in both skeletal muscle and liver tissue after exercise. Exercise and PKCβ deficiency can alleviate HFD-induced insulin resistance, as evidenced by improved insulin tolerance. In addition, fat accumulation and mitochondrial dysfunction induced by HFD were also ameliorated by both exercise and PKCβ deficiency. On the other hand, exercise had little effect on PKCβ(-/- mice. Further, our data indicated improved activation of AKT, the downstream signal molecule of insulin, in skeletal muscle and liver of exercised mice, whereas PKCβ deficiency blunted the difference between sedentary and exercised mice. These results suggest that downregulation of PKCβ contributes to exercise-induced improvement of insulin resistance in HFD-fed mice.

  8. Dietary sardine protein lowers insulin resistance, leptin and TNF-α and beneficially affects adipose tissue oxidative stress in rats with fructose-induced metabolic syndrome.

    Science.gov (United States)

    Madani, Zohra; Louchami, Karim; Sener, Abdullah; Malaisse, Willy J; Ait Yahia, Dalila

    2012-02-01

    The present study aims at exploring the effects of sardine protein on insulin resistance, plasma lipid profile, as well as oxidative and inflammatory status in rats with fructose-induced metabolic syndrome. Rats were fed sardine protein (S) or casein (C) diets supplemented or not with high-fructose (HF) for 2 months. Rats fed the HF diets had greater body weight and adiposity and lower food intake as compared to control rats. Increased plasma glucose, insulin, HbA1C, triacylglycerols, free fatty acids and impaired glucose tolerance and insulin resistance was observed in HF-fed rats. Moreover, a decline in adipose tissues antioxidant status and a rise in lipid peroxidation and plasma TNF-α and fibrinogen were noted. Rats fed sardine protein diets exhibited lower food intake and fat mass than those fed casein diets. Sardine protein diets diminished plasma insulin and insulin resistance. Plasma triacylglycerol and free fatty acids were also lower, while those of α-tocopherol, taurine and calcium were enhanced as compared to casein diets. Moreover, S-HF diet significantly decreased plasma glucose and HbA1C. Sardine protein consumption lowered hydroperoxide levels in perirenal and brown adipose tissues. The S-HF diet, as compared to C-HF diet decreased epididymal hydroperoxides. Feeding sardine protein diets decreased brown adipose tissue carbonyls and increased glutathione peroxidase activity. Perirenal and epididymal superoxide dismutase and catalase activities and brown catalase activity were significantly greater in S-HF group than in C-HF group. Sardine protein diets also prevented hyperleptinemia and reduced inflammatory status in comparison with rats fed casein diets. Taken together, these results support the beneficial effect of sardine protein in fructose-induced metabolic syndrome on such variables as hyperglycemia, insulin resistance, hyperlipidemia and oxidative and inflammatory status, suggesting the possible use of sardine protein as a protective

  9. Cross-Resistance between Cry1 Proteins in Fall Armyworm (Spodoptera frugiperda) May Affect the Durability of Current Pyramided Bt Maize Hybrids in Brazil.

    Science.gov (United States)

    Bernardi, Daniel; Salmeron, Eloisa; Horikoshi, Renato Jun; Bernardi, Oderlei; Dourado, Patrick Marques; Carvalho, Renato Assis; Martinelli, Samuel; Head, Graham P; Omoto, Celso

    2015-01-01

    Genetically modified plants expressing insecticidal proteins from Bacillus thuringiensis (Bt) offer valuable options for managing insect pests with considerable environmental and economic benefits. Despite the benefits provided by Bt crops, the continuous expression of these insecticidal proteins imposes strong selection for resistance in target pest populations. Bt maize (Zea mays) hybrids have been successful in controlling fall armyworm (Spodoptera frugiperda), the main maize pest in Brazil since 2008; however, field-evolved resistance to the protein Cry1F has recently been reported. Therefore it is important to assess the possibility of cross-resistance between Cry1F and other Cry proteins expressed in Bt maize hybrids. In this study, an F2 screen followed by subsequent selection on MON 89034 maize was used to select an S. frugiperda strain (RR) able to survive on the Bt maize event MON 89034, which expresses the Cry1A.105 and Cry2Ab2 proteins. Field-collected insects from maize expressing the Cry1F protein (event TC1507) represented most of the positive (resistance allele-containing) (iso)families found. The RR strain showed high levels of resistance to Cry1F, which apparently also conferred high levels of cross resistance to Cry1A.105 and Cry1Ab, but had only low-level (10-fold) resistance to Cry2Ab2. Life history studies to investigate fitness costs associated with the resistance in RR strain revealed only small reductions in reproductive rate when compared to susceptible and heterozygous strains, but the RR strain produced 32.2% and 28.4% fewer females from each female relative to the SS and RS (pooled) strains, respectively. Consistent with the lack of significant resistance to Cry2Ab2, MON 89034 maize in combination with appropriate management practices continues to provide effective control of S. frugiperda in Brazil. Nevertheless, the occurrence of Cry1F resistance in S. frugiperda across Brazil, and the cross-resistance to Cry1Ab and Cry1A.105

  10. Cross-Resistance between Cry1 Proteins in Fall Armyworm (Spodoptera frugiperda May Affect the Durability of Current Pyramided Bt Maize Hybrids in Brazil.

    Directory of Open Access Journals (Sweden)

    Daniel Bernardi

    Full Text Available Genetically modified plants expressing insecticidal proteins from Bacillus thuringiensis (Bt offer valuable options for managing insect pests with considerable environmental and economic benefits. Despite the benefits provided by Bt crops, the continuous expression of these insecticidal proteins imposes strong selection for resistance in target pest populations. Bt maize (Zea mays hybrids have been successful in controlling fall armyworm (Spodoptera frugiperda, the main maize pest in Brazil since 2008; however, field-evolved resistance to the protein Cry1F has recently been reported. Therefore it is important to assess the possibility of cross-resistance between Cry1F and other Cry proteins expressed in Bt maize hybrids. In this study, an F2 screen followed by subsequent selection on MON 89034 maize was used to select an S. frugiperda strain (RR able to survive on the Bt maize event MON 89034, which expresses the Cry1A.105 and Cry2Ab2 proteins. Field-collected insects from maize expressing the Cry1F protein (event TC1507 represented most of the positive (resistance allele-containing (isofamilies found. The RR strain showed high levels of resistance to Cry1F, which apparently also conferred high levels of cross resistance to Cry1A.105 and Cry1Ab, but had only low-level (10-fold resistance to Cry2Ab2. Life history studies to investigate fitness costs associated with the resistance in RR strain revealed only small reductions in reproductive rate when compared to susceptible and heterozygous strains, but the RR strain produced 32.2% and 28.4% fewer females from each female relative to the SS and RS (pooled strains, respectively. Consistent with the lack of significant resistance to Cry2Ab2, MON 89034 maize in combination with appropriate management practices continues to provide effective control of S. frugiperda in Brazil. Nevertheless, the occurrence of Cry1F resistance in S. frugiperda across Brazil, and the cross-resistance to Cry1Ab and Cry1A

  11. Effects of resistance training and protein supplementation on bone turnover in young adult women

    Directory of Open Access Journals (Sweden)

    Sinning Wayne E

    2005-08-01

    Full Text Available Abstract Background The strength of aging bone depends on the balance between the resorption and formation phases of the remodeling process. The purpose of this study was to examine the interaction of two factors with the potential to exert opposing influences on bone turnover, resistance exercise training and high dietary protein intake. It was hypothesized that resistance training by young, healthy, untrained women with protein intakes near recommended levels (0.8 g·kg-1·d-1 would promote bone formation and/or inhibit bone resorption, and that subsequent supplementation to provide 2.4 g protein·kg-1·d-1 would reverse these effects. Methods Bone formation was assessed with serum bone-specific alkaline phosphatase (BAP and osteocalcin (OC, and bone resorption with urinary calcium and deoxypyridinoline (DPD. Biochemical, strength, anthropometric, dietary, and physical activity data were obtained from 24 healthy, untrained, eumenorrheic women (18–29y at baseline, after eight weeks of resistance training (3 d·wk-1, ~1 hr·d-1; 3 sets, 6–10 repetitions, 13 exercises, 75–85% maximum voluntary contraction, and after 12 weeks of resistance training and 10 days of protein/placebo supplementation. Subjects were randomized (double-blind to either a high protein (HP or training control (TC group and, during the final 10 days, consumed either enough purified whey protein to bring daily protein intake to 2.4 g·kg-1·d-1, or an equivalent dose of isoenergetic, carbohydrate placebo. Results Strength, lean tissue mass, and DPD increased significantly in both groups over time, while percent body fat and BAP decreased (repeated measures ANOVA, p ≤ 0.05, Bonferroni correction. No significant changes were observed for serum OC or urinary calcium, and no significant group (TC, HP × time (baseline, week 8, week 12 interactions emerged for any of the biochemical measures. Conclusion (1 Twelve weeks of high-intensity resistance training did not appear to

  12. Swelling Index of Glutenin (SIG) Related to Protein Quality,Dough Characters and Noodle Quality

    Institute of Scientific and Technical Information of China (English)

    HU Xin-zhong; WEI Yi-min; M I P Kovacs; WANG Chun

    2004-01-01

    The swelling index of glutenin (SIG) and the protein fraction of 25 Chinese wheat varieties were studied with new protein fractions extracting method. The protein fractions compose of monomeric protein, soluble glutenin and insoluble glutenin. The relations between other protein index, dough character, and fresh noodle quality were also discussed. The SIG results at different time is positively and highly significantly related to the insoluble glutenin content (r=0.808 -0.867, P< 0.01). The SIG result can reflect the insoluble glutenin content. The protein content, gluten index, farinograph stability time, extensibility length and extensigramenergy were positively and significantly correlated with SIG5 and SIG20 (r=0.516- 0.734, P<0.05, 0.01).SIG proved to be applicable in Chinese wheat dough evaluation. Fresh noodle making quality parameters were evaluated by fresh noodle length, thickness, maximum resistance to extension, extension area and extension distance, while cooked noodle texture was determined by cutting firmness, compression recovery, surface firmness and TPA by using a texture analyzer of TA.XT2i.The noodle cooking quality was significantly correlated with SIG value. The surface firmness and cutting firmness were more desirable for predicating the quality difference than TPA test and compression. Cooking loss and water absorption were negatively related to SIG value and insoluble content (r=-0.556 - - 0.787, P< 0.05, 0.01) . The results showed that SIG test was also suitable in evaluating noodle making and cooking quality in very small sample size, which was very important in wheat breeding programs. Therefore,SIG test, as a small scale test, is suitable to evaluate dough rheological properties for Chinese wheat varieties, and will be helpful in cereal research and wheat breeding program, especially, in early generations.

  13. Identification of Adenyl Cyclase Activity in a Disease Resistance Protein in Arabidopsis thaliana

    KAUST Repository

    Hussein, Rana

    2012-11-01

    Cyclic nucleotide, cAMP, is an important signaling molecule in animals and plants. However, in plants the enzymes that synthesize this second messenger, adenyl cyclases (ACs), remain elusive. Given the physiological importance of cAMP in signaling, particularly in response to biotic and abiotic stresses, it is thus important to identify and characterize ACs in higher plants. Using computational approaches, a disease resistance protein from Arabidopsis thaliana, At3g04220 was found to have an AC catalytic center motif. In an attempt to prove that this candidate has adenyl cyclases activity in vitro, the coding sequence of the putative AC catalytic domain of this protein was cloned and expressed in E. coli and the recombinant protein was purified. The nucleotide cyclase activity of the recombinant protein was examined using cyclic nucleotide enzyme immunoassays. In parallel, the expression of At3g04220 was measured in leaves under three different stress conditions in order to determine under which conditions the disease resistance protein could function. Results show that the purified recombinant protein has Mn2+ dependent AC activity in vitro, and the expression analysis supports a role for At3g04220 and cAMP in plant defense.

  14. Soil moisture - resistivity relation at the plot and catchment scale

    Science.gov (United States)

    Calamita, Giuseppe; Perrone, Angela; Satriani, Antonio; Brocca, Luca; Moramarco, Tommaso

    2010-05-01

    The key role played by soil moisture in both Global Hydrological Cycle and Earth Radiation Budget has been claimed by numerous authors during past decades. The importance of this environmental variable is evident in several natural processes operating in a wide range of spatial and temporal scales. At continental and regional scales soil moisture influences the evapotranspiration process and so acts indirectly on the climate processes; at middle scale is one of the major controls of the infiltration-runoff soil response during rainfall events; at small scales the knowledge of soil moisture evolution is crucial for precision agriculture and the associated site-specific management practices. However, soil moisture exhibits an high temporal and spatial variability and this is even more evident in the vadose zone. Thus, in order to better understand the soil moisture dynamics it is desirable to capture its behavior at different temporal and/or spatial scales. Traditional in situ methods to measure soil moisture like TDR can be very precise and allows an high temporal resolution. Recently, the application in field of geophysical methods for capturing soil moisture spatial and temporal variations has demonstrated to be a promising tool for hydro-geological studies. One of the major advantages relies on the capability to capture the soil moisture variability at larger scales, that is decametric or hectometric scale. In particular, this study is based on the simultaneous application of the electrical resistivity and the TDR methods. We present two study cases that differ from each other by both spatial and temporal resolution. For the first one, simultaneous measurements obtained during four different period of the year and carried out within a test catchment (~60 km2) in Umbria region (central Italy) were analyzed. The second case concerns almost three months of simultaneous measurements carried out in a small test site ( sampling events during 80 days. In both case we

  15. Resistance training improves isokinetic strength and metabolic syndrome-related phenotypes in postmenopausal women

    Directory of Open Access Journals (Sweden)

    Oliveira PFA

    2015-08-01

    Full Text Available Pedro Ferreira Alves Oliveira,1 André Bonadias Gadelha,2 Rafael Gauche,2 Flávio Macedo Lahud Paiva,2 Martim Bottaro,2 Lauro C Vianna,2 Ricardo Moreno Lima2 1Department of Physical Education, Instituto Federal de Brasília, 2College of Physical Education, University of Brasília, Brasília, DF, Brazil Purpose: To examine the effects of resistance training (RT on metabolic syndrome-related phenotypes in postmenopausal women. Patients and methods: Twenty-two postmenopausal women (65.0±4.2 years underwent 12 weeks of whole body progressive training with intensity prescribed based on rating of perceived exertion. Dominant knee extension strength was assessed using an isokinetic dynamometer before and after the intervention. Moreover, all volunteers had blood samples collected for lipid profile, glycemic control, and C-reactive protein analyses. Waist circumference and arterial blood pressure were also measured at baseline and after the training period. Student’s t-tests for paired samples and repeated measures ANOVA were used to compare dependent variables, and statistical significance was set at P<0.05. Results: Isokinetic muscle strength significantly increased (P<0.01 with training. It was observed that waist circumference as well as total and low-density lipoprotein cholesterol levels significantly decreased with training (P<0.01. Total cholesterol/high-density lipoprotein cholesterol ratio, an important marker of cardiovascular disease incidence, was also significantly reduced (from 3.91±0.91 to 3.60±0.74; P<0.01 after the program. Blood glucose, basal insulin, and homeostatic model assessment of insulin resistance were also significantly reduced (P<0.01. No significant alterations were observed for resting blood pressure, triglycerides, or C-reactive protein. Conclusion: Based on the observed results, it can be concluded that a 12-week progressive RT program, besides increasing isokinetic muscle strength, induces beneficial alterations

  16. 大鼠肝脏组织视黄醇结合蛋白4在衰老过程中表达及与胰岛素抵抗的关系%The increased expression of retinol binding protein 4 during aging in rat liver and the relation to insulin resistance

    Institute of Scientific and Technical Information of China (English)

    王兆君; 张秀锦; 何疆春; 杨晔; 叶平

    2012-01-01

    Objective;To investigate difference expression of retinol binding protein 4( RBP4) during aging in liver tissue of rat and explore the molecular mechanism of insulin resistance(IR). Methods: We used the minimal model technique of Bergman to estimate the insulin sensitivity of young(8 - 12 weeks) and aged (24months) rat. The levels of RBP4 and peroxisome proliferator-activated receptora ( PPARα) mRNA were measured by reverse transcription-polymerse chain reaction ( RT-PCR) and the proteins of RBP4 and PPARα were determined by western blotting,respectively. Results;The degree of IR in the aged group was significantly increased compared with that in the young group. The RBP4mRNA and protein of the aged group were significantly increased. The PPARα mRNA and protein of the aged group were significantly decreased. Conclusion: The mechanism of IR during aging is probably associated with the increased expression of RBP4 in rat liver.%目的:观察大鼠肝脏组织视黄醇结合蛋白4( retinol binding protein4,RBP4)在衰老过程中表达差异,在分子水平上探讨衰老过程中出现胰岛素抵抗(insulin resistance,IR)的可能机制.方法:用Bergman创立的微小模型技术评价年轻鼠(8~12周龄)和老年鼠(24个月龄)的胰岛素敏感性,取大鼠肝脏组织提取总RNA,采用半定量RT-PCR法检测RBP4和过氧化体增殖物激活型受体α(peroxisome proliferator-activated receptorα,PPARα)mRNA水平,用Western blot法检测RBP4和PPARα蛋白表达情况.结果:与年轻鼠组比较,老年鼠组存在明显的胰岛素抵抗,而老年鼠组的RBP4mRNA及蛋白表达明显升高,PPARαmRNA及蛋白表达明显减少.结论:衰老过程中大鼠肝脏组织RBP4表达升高可能与胰岛素抵抗有关.

  17. Identification and characterization of functionally important elements in the multidrug resistance protein 1 COOH-terminal region.

    Science.gov (United States)

    Westlake, Christopher J; Payen, Lea; Gao, Mian; Cole, Susan P C; Deeley, Roger G

    2004-12-17

    The ATP binding cassette (ABC) transporter, multidrug resistance protein 1 (MRP1/ABCC1), transports a broad spectrum of conjugated and unconjugated compounds, including natural product chemotherapeutic agents. In this study, we have investigated the importance of the COOH-terminal region of MRP1 for transport activity and basolateral plasma membrane trafficking. The COOH-terminal regions of some ABCC proteins have been implicated in protein trafficking, but the function of this region of MRP1 has not been defined. In contrast to results obtained with other ABCC proteins, we found that the COOH-proximal 30 amino acids of MRP1 can be removed without affecting trafficking to basolateral membranes. However, the truncated protein is inactive. Furthermore, removal of as few as 4 COOH-terminal amino acids profoundly decreases transport activity. Although amino acid sequence conservation of the COOH-terminal regions of ABC proteins is low, secondary structure predictions indicate that they consist of a broadly conserved helix-sheet-sheet-helix-helix structure. Consistent with a conservation of secondary and tertiary structure, MRP1 hybrids containing the COOH-terminal regions of either the homologous MRP2 or the distantly related P-glycoprotein were fully active and trafficked normally. Using mutated proteins, we have identified structural elements containing five conserved hydrophobic amino acids that are required for activity. We show that these are important for binding and hydrolysis of ATP by nucleotide binding domain 2. Based on crystal structures of several ABC proteins, we suggest that the conserved amino acids may stabilize a helical bundle formed by the COOH-terminal three helices and may contribute to interactions between the COOH-terminal region and the protein's two nucleotide binding domains.

  18. Correlation between tension softening relation and crack extension resistance in concrete

    Institute of Scientific and Technical Information of China (English)

    Xiufang ZHANG; Shilang XU

    2009-01-01

    Changes of the material fracture toughness with crack propagation can be described by a crack extension resistance curve, one of the fundamental fracture criteria in crack mechanics. Recently, experimental observation of the fracture behavior in concrete was used to develop a new fracture criterion, the crack extension GR resistance curve, to analyze crack propagation during the entire concrete fracture process. The variation of the crack extension resistance is mainly associated with the energy consumption in the fracture process zone ahead of the stress-free crack tip. The crack extension resistance is then a function of the softening curve, which is a basic mechanical property in the fracture process zone. The relationship between the softening curve and the crack extension GR resistance curve is then analyzed based on results of three-point bending beams tests. The results indicate that the characteristic points of the crack extension resistance GR curve is closely related to the characteristic point on used tension softening curve.

  19. Resistance to activated protein C is a risk factor for fibrostenosis in Crohn's disease

    Institute of Scientific and Technical Information of China (English)

    Gottfried Novacek; Wolfgang Miehsler; Julia Palkovits; Walter Reinisch; Thomas Waldh(o)r; Stylianos Kapiotis; Alfred Gangl; Harald Vogelsang

    2006-01-01

    AIM: To evaluate the effect of resistance to activated protein C (aPCR), the most common known inherited thrombophilic disorder, on the risk of intestinal operation of fibrostenosis in patients with Crohn's disease (CD).METHODS: In a previous study, we assessed the prevalence of aPCR in CD. In a retrospective casecontrolled study, 8 of these CD patients with aPCR were now compared with 24 CD patients without aPCR,matched by gender, age at diagnosis and duration of disease in a 1:3 fashion. The primary end point was the occurrence of an intestinal CD-related operation with evidence of fibrostenosis in the bowel resection specimen.RESULTS: The Kaplan-Meier analysis revealed that patients with aPCR had a lower probability of remaining free of operation with fibrostenosis than patients without aPCR (P = 0.0372; exact log-rank test) resulting in a significantly shorter median time interval from diagnosis of CD to the first operation with fibrostenosis (32 vs 160mo). At 10 years, the likelihood of remaining free of operation with fibrostenosis was 25% for patients with aPCR and 57.8% for patients without aPCR.CONCLUSION: CD patients with aPCR are at higher risk to undergo intestinal operation of fibrostenosis than those without aPCR. This supports our hypothesis of aPCR being a possible risk factor for fibrostenosis in CD.

  20. Increased Systemic Exposure of Methotrexate by a Polyphenol-Rich Herb via Modulation on Efflux Transporters Multidrug Resistance-Associated Protein 2 and Breast Cancer Resistance Protein.

    Science.gov (United States)

    Yu, Chung-Ping; Hsieh, Yun-Chung; Shia, Chi-Sheng; Hsu, Pei-Wen; Chen, Jen-Yuan; Hou, Yu-Chi; Hsieh, Yo-Wen

    2016-01-01

    Scutellariae radix (SR, roots of Scutellaria baicalensis Georgi), a popular Chinese medicine, contains plenty of flavonoids such as baicalin, wogonoside, baicalein, and wogonin. Methotrexate (MTX), an important immunosuppressant with a narrow therapeutic index, is a substrate of multidrug resistance-associated proteins (MRPs) and breast cancer resistance protein (BCRP). This study investigated the effect of SR on MTX pharmacokinetics and the underlying mechanisms. Rats were orally administered MTX alone and with 1.0 or 2.0 g/kg of SR. The serum concentrations of MTX were determined by a fluorescence polarization immunoassay. Cell models were used to explore the involvement of MRP2 and BCRP in the interaction. The results showed that 1.0 g/kg of SR significantly increased Cmax, AUC(0-30), AUC(0-2880), and mean residence time (MRT) of MTX by 50%, 45%, 501%, and 347%, respectively, and 2.0 g/kg of SR significantly enhanced the AUC(0-2880) and MRT by 242% and 293%, respectively, but decreased AUC(0-30) by 41%. Cell line studies indicated that SR activated the BCRP-mediated efflux transport, whereas the serum metabolites of SR inhibited both the BCRP- and MRP2-mediated efflux transports. In conclusion, SR ingestion increased the systemic exposure and MRT of MTX via modulation on MRP2 and BCRP.

  1. Bovine spongiform encephalopathy induces misfolding of alleged prion-resistant species cellular prion protein without altering its pathobiological features.

    Science.gov (United States)

    Vidal, Enric; Fernández-Borges, Natalia; Pintado, Belén; Ordóñez, Montserrat; Márquez, Mercedes; Fondevila, Dolors; Torres, Juan María; Pumarola, Martí; Castilla, Joaquín

    2013-05-01

    Bovine spongiform encephalopathy (BSE) prions were responsible for an unforeseen epizootic in cattle which had a vast social, economic, and public health impact. This was primarily because BSE prions were found to be transmissible to humans. Other species were also susceptible to BSE either by natural infection (e.g., felids, caprids) or in experimental settings (e.g., sheep, mice). However, certain species closely related to humans, such as canids and leporids, were apparently resistant to BSE. In vitro prion amplification techniques (saPMCA) were used to successfully misfold the cellular prion protein (PrP(c)) of these allegedly resistant species into a BSE-type prion protein. The biochemical and biological properties of the new prions generated in vitro after seeding rabbit and dog brain homogenates with classical BSE were studied. Pathobiological features of the resultant prion strains were determined after their inoculation into transgenic mice expressing bovine and human PrP(C). Strain characteristics of the in vitro-adapted rabbit and dog BSE agent remained invariable with respect to the original cattle BSE prion, suggesting that the naturally low susceptibility of rabbits and dogs to prion infections should not alter their zoonotic potential if these animals became infected with BSE. This study provides a sound basis for risk assessment regarding prion diseases in purportedly resistant species.

  2. Microparticulation of whey protein: related factors affecting the solubility.

    Science.gov (United States)

    Lieske, B; Konrad, G

    1994-10-01

    Solubility of Simplesse 100, the only whey-based fat substitute, was found to be good, considering the fact that technology for preparation of Simplesse 100 is a sequence of thermal steps. To characterize this phenomen, gel chromatography on Sephadex G-100, Sephacryl S-1000 and SDS-PAGE were used, supported by high-speed separation, UV studies and analytical procedures. Results show that the unusual solubility characteristic of microparticulated whey protein is related to two molecular effects: (1) optimal defolding of protein molecules and (2) stabilization of the defolded status by carbohydrate. Both effects were considered to favour non-covalent bonds, which contribute to the outstanding physico-functional and nutritive properties of microparticles.

  3. Sensitivity of protein adsorption to architectural variations in a protein-resistant polymer brush containing engineered nanoscale adhesive sites.

    Science.gov (United States)

    Gon, Saugata; Santore, Maria M

    2011-12-20

    Patchy polymer brushes contain nanoscale (5-15 nm) adhesive elements, such as polymer coils or nanoparticles, embedded at their base at random positions on the surface. The competition between the brush's steric (protein resistant) repulsions and the attractions from the discrete adhesive elements provides a precise means to control bioadhesion. This differs from the classical approach, where functionality is placed on the brush's periphery. The current study demonstrates the impact of poly(etheylene glycol) (PEG) brush architecture and ionic strength on fibrinogen adsorption on brushes containing embedded poly-l-lysine (PLL, 20K MW) coils or "patches". The consistent appearance of a fibrinogen adsorption threshold, a minimum loading of patches on the surface, below which protein adsorption does not occur, suggests multivalent protein capture: Adsorbing proteins simultaneously engage several patches. The surface composition (patch loading) at the threshold is extremely sensitive to the brush height and ionic strength, varying up to a factor of 5 in the surface loading of the PLL patches (~50% of the range of possible surfaces). Variations in ionic strength have a similar effect, with the smallest thresholds seen for the largest Debye lengths. While trends with brush height were the clearest and most dominant, consideration of the PEG loading within the brush or its persistence length did not reveal a critical brush parameter for the onset of adsorption. The lack of straightforward correlation on brush physics was likely a result of multivalent binding, (producing an additional dependence on patch loading), and might be resolved for univalent adsorption onto more strongly binding patches. While studies with similar brushes placed uniformly on a surface revealed that the PEG loading within the brush is the best indicator of protein resistance, the current results suggest that brush height is more important for patchy brushes. Likely the interactions producing brush

  4. Pathogenesis-related proteins protect extrafloral nectar from microbial infestation.

    Science.gov (United States)

    González-Teuber, Marcia; Eilmus, Sascha; Muck, Alexander; Svatos, Ales; Heil, Martin

    2009-05-01

    Plants in more than 300 genera produce extrafloral nectar (EFN) to attract carnivores as a means of indirect defence against herbivores. As EFN is secreted at nectaries that are not physically protected from the environment, and contains carbohydrates and amino acids, EFN must be protected from infestation by micro-organisms. We investigated the proteins and anti-microbial activity in the EFN of two Central American Acacia myrmecophytes (A. cornigera and A. hindsii) and two related non-myrmecophytes (A. farnesiana and Prosopis juliflora). Acacia myrmecophytes secrete EFN constitutively at high rates to nourish the ants inhabiting these plants as symbiotic mutualists, while non-myrmecophytes secrete EFN only in response to herbivore damage to attract non-symbiotic ants. Thus, the quality and anti-microbial protection of the EFN secreted by these two types of plants were likely to differ. Indeed, myrmecophyte EFN contained significantly more proteins than the EFN of non-myrmecophytes, and was protected effectively from microbial infestation. We found activity for three classes of pathogenesis-related (PR) enzymes: chitinase, beta-1,3-glucanase and peroxidase. Chitinases and beta-1,3-glucanases were significantly more active in myrmecophyte EFN, and chitinase at the concentrations found in myrmecophyte EFN significantly inhibited yeast growth. Of the 52 proteins found in A. cornigera EFN, 28 were annotated using nanoLC-MS/MS data, indicating that chitinases and glucanases contribute more than 50% of the total protein content in the EFN of this myrmecophyte. Our study demonstrates that PR enzymes play an important role in protecting EFN from microbial infestation.

  5. Beta-lactam resistance response triggered by inactivation of a nonessential penicillin-binding protein.

    Directory of Open Access Journals (Sweden)

    Bartolomé Moya

    2009-03-01

    Full Text Available It has long been recognized that the modification of penicillin-binding proteins (PBPs to reduce their affinity for beta-lactams is an important mechanism (target modification by which Gram-positive cocci acquire antibiotic resistance. Among Gram-negative rods (GNR, however, this mechanism has been considered unusual, and restricted to clinically irrelevant laboratory mutants for most species. Using as a model Pseudomonas aeruginosa, high up on the list of pathogens causing life-threatening infections in hospitalized patients worldwide, we show that PBPs may also play a major role in beta-lactam resistance in GNR, but through a totally distinct mechanism. Through a detailed genetic investigation, including whole-genome analysis approaches, we demonstrate that high-level (clinical beta-lactam resistance in vitro, in vivo, and in the clinical setting is driven by the inactivation of the dacB-encoded nonessential PBP4, which behaves as a trap target for beta-lactams. The inactivation of this PBP is shown to determine a highly efficient and complex beta-lactam resistance response, triggering overproduction of the chromosomal beta-lactamase AmpC and the specific activation of the CreBC (BlrAB two-component regulator, which in turn plays a major role in resistance. These findings are a major step forward in our understanding of beta-lactam resistance biology, and, more importantly, they open up new perspectives on potential antibiotic targets for the treatment of infectious diseases.

  6. Transgenic Sugarcane Resistant to Sorghum mosaic virus Based on Coat Protein Gene Silencing by RNA Interference

    Directory of Open Access Journals (Sweden)

    Jinlong Guo

    2015-01-01

    Full Text Available As one of the critical diseases of sugarcane, sugarcane mosaic disease can lead to serious decline in stalk yield and sucrose content. It is mainly caused by Potyvirus sugarcane mosaic virus (SCMV and/or Sorghum mosaic virus (SrMV, with additional differences in viral strains. RNA interference (RNAi is a novel strategy for producing viral resistant plants. In this study, based on multiple sequence alignment conducted on genomic sequences of different strains and isolates of SrMV, the conserved region of coat protein (CP genes was selected as the target gene and the interference sequence with size of 423 bp in length was obtained through PCR amplification. The RNAi vector pGII00-HACP with an expression cassette containing both hairpin interference sequence and cp4-epsps herbicide-tolerant gene was transferred to sugarcane cultivar ROC22 via Agrobacterium-mediated transformation. After herbicide screening, PCR molecular identification, and artificial inoculation challenge, anti-SrMV positive transgenic lines were successfully obtained. SrMV resistance rate of the transgenic lines with the interference sequence was 87.5% based on SrMV challenge by artificial inoculation. The genetically modified SrMV-resistant lines of cultivar ROC22 provide resistant germplasm for breeding lines and can also serve as resistant lines having the same genetic background for study of resistance mechanisms.

  7. Identifying Novel Candidate Genes Related to Apoptosis from a Protein-Protein Interaction Network

    Directory of Open Access Journals (Sweden)

    Baoman Wang

    2015-01-01

    Full Text Available Apoptosis is the process of programmed cell death (PCD that occurs in multicellular organisms. This process of normal cell death is required to maintain the balance of homeostasis. In addition, some diseases, such as obesity, cancer, and neurodegenerative diseases, can be cured through apoptosis, which produces few side effects. An effective comprehension of the mechanisms underlying apoptosis will be helpful to prevent and treat some diseases. The identification of genes related to apoptosis is essential to uncover its underlying mechanisms. In this study, a computational method was proposed to identify novel candidate genes related to apoptosis. First, protein-protein interaction information was used to construct a weighted graph. Second, a shortest path algorithm was applied to the graph to search for new candidate genes. Finally, the obtained genes were filtered by a permutation test. As a result, 26 genes were obtained, and we discuss their likelihood of being novel apoptosis-related genes by collecting evidence from published literature.

  8. The overexpression of MRP4 is related to multidrug resistance in osteosarcoma cells

    Directory of Open Access Journals (Sweden)

    Zhonghui He

    2015-01-01

    Full Text Available Doxorubicin (Adriamycin, ADM is an antimitotic drug used in the treatment of a wide range of malignant tumors, including acute leukemia, lymphoma, osteosarcoma, breast cancer, and lung cancer. Multidrug resistance-associated proteins (MRPs are members of a superfamily of ATP-binding cassette (ABC transporters, which can transport various molecules across extra- and intra-cellular membranes. The aim of this study was to investigate whether there was a correlation between MRP4 and primary ADM resistance in osteosarcoma cells. In this paper, we chose the human osteosarcoma cell line MG63, ADM resistant cell line MG63/DOX, and the patient′s primary cell GSF-0686. We checked the ADM sensitivity and cytotoxicity of all the three cells by cell proliferation assay. The intracellular drug concentrations were measured by using LC-MS/MS. We also examined MRP4 gene expression by RT-PCR and Western Blot. We found that the intracellular ADM concentration of the parent osteosarcoma cell line MG63 was higher than the ADM resistant osteosarcoma MG63/DOX cell line or the GSF-0686 cell after ADM treatment (P < 0.05. In addition, MRP4 mRNA and protein levels in ADM resistant osteosarcoma cells were higher than in MG63 cell (P < 0.05. Taking together, this work suggests that overexpression of MRP4 may confer ADM resistance in osteosarcoma cells.

  9. A TolC-Like Protein of Actinobacillus pleuropneumoniae Is Involved in Antibiotic Resistance and Biofilm Formation

    Science.gov (United States)

    Li, Ying; Cao, Sanjie; Zhang, Luhua; Lau, Gee W.; Wen, Yiping; Wu, Rui; Zhao, Qin; Huang, Xiaobo; Yan, Qigui; Huang, Yong; Wen, Xintian

    2016-01-01

    Actinobacillus pleuropneumoniae is the etiologic agent of porcine contagious pleuropneumonia, a significant disease that causes serious economic losses to the swine industry worldwide. Persistent infections caused by bacterial biofilms are recalcitrant to treat because of the particular drug resistance of biofilm-dwelling cells. TolC, a key component of multidrug efflux pumps, are responsible for multidrug resistance (MDR) in many Gram-negative bacteria. In this study, we identified two TolC-like proteins, TolC1 and TolC2, in A. pleuropneumoniae. Deletion of tolC1, but not tolC2, caused a significant reduction in biofilm formation, as well as increased drug sensitivity of both planktonic and biofilm cells. The genetic-complementation of the tolC1 mutation restored the competent biofilm and drug resistance. Besides, biofilm formation was inhibited and drug sensitivity was increased by the addition of phenylalanine-arginine beta-naphthylamide (PAβN), a well-known efflux pump inhibitor (EPI), suggesting a role for EPI in antibacterial strategies toward drug tolerance of A. pleuropneumoniae. Taken together, TolC1 is required for biofilm formation and is a part of the MDR machinery of both planktonic and biofilm cells, which could supplement therapeutic strategies for resistant bacteria and biofilm-related infections of A. pleuropneumoniae clinical isolate SC1516. PMID:27822201

  10. 革兰氏阴性细菌外膜蛋白耐药功能及其抑菌策略研究进展%An review on the antibiotics resistance function of outer membrane protein in gram-negative bacterial and related antimicrobial strategies

    Institute of Scientific and Technical Information of China (English)

    李碗芯; 孙莉娜; 林向民

    2015-01-01

    The emergence of bacterial resistance to drug use has posed serious problem worldwide. Generally, the drug resistance ca-pability of gram-negative bacteria is stronger than that of gram-positive, which is partially attributed to the antibiotics resistance of the outer membrane proteins ( OMPs) . It is well known that the specific OMPs efflux antibiotics out or inhibits uptakes of antibiot-ics, while the regulation mechanism remains uncertain. With the development of modern science and technology, especially the ap-plication of structure biology, molecular biology and proteomics, many progressive studies have unveiled the mechanisms underlying the antibiotic resistance of OMPs. This review focuses on the recent advances in the structure and antibiotic resistance mechanisms of OMP, which provides helpful insight into manufacture of new OMPs-targeting antimicrobial drug.%当前细菌耐药的形势日益严峻,已引起全世界的广泛关注.革兰氏阴性细菌的耐药性普遍比革兰氏阳性细菌强,这与镶嵌或锚定在革兰氏阴性细菌外膜上的蛋白耐药功能密切相关.目前已知外膜蛋白能够阻碍抗生素通过外膜以及将抗生素排出胞外等方式使细菌产生耐药性,但具体的耐药与调控机制还有待进一步研究.近年来,随着现代科学技术的不断发展,特别是结构生物学、分子生物学与蛋白质组学在该领域的充分运用,有关外膜蛋白功能的研究和技术取得了很大的进步.本文对近年来国内外在细菌外膜蛋白的结构与耐药机理、耐药新功能及新机制等方面的研究进展进行了概述,为揭示革兰氏阴性菌耐药形成机制奠定基础.

  11. Drought resistance of Ailanthus altissima: root hydraulics and water relations.

    Science.gov (United States)

    Trifilò, P; Raimondo, F; Nardini, A; Lo Gullo, M A; Salleo, S

    2004-01-01

    Drought resistance of Ailanthus altissima (Mill.) Swingle is a major factor underlying the impressively wide expansion of this species in Europe and North America. We studied the specific mechanism used by A. altissima to withstand drought by subjecting potted seedlings to four irrigation regimes. At the end of the 13-week treatment period, soil water potential was -0.05 MPa for well-watered control seedlings (W) and -0.4, -0.8 and -1.7 MPa for drought-stressed seedlings (S) in irrigation regimes S1, S2 and S3, respectively. Root and shoot biomass production did not differ significantly among the four groups. A progressively marked stomatal closure was observed in drought-stressed seedlings, leading to homeostasis of leaf water potential, which was maintained well above the turgor loss point. Root and shoot hydraulics were measured with a high-pressure flow meter. When scaled by leaf surface area, shoot hydraulic conductance did not differ among the treated seedlings, whereas root hydraulic conductance decreased by about 20% in S1 and S2 seedlings and by about 70% in S3 seedlings, with respect to the well-watered control value. Similar differences were observed when root hydraulic conductance was scaled by root surface area, suggesting that roots had become less permeable to water. Anatomical observations of root cross sections revealed that S3 seedlings had shrunken cortical cells and a multilayer endodermal-like tissue that probably impaired soil-to-root stele water transport. We conclude that A. altissima seedlings are able to withstand drought by employing a highly effective water-saving mechanism that involves reduced water loss by leaves and reduced root hydraulic conductance. This water-saving mechanism helps explain how A. altissima successfully competes with native vegetation.

  12. Parathyroid hormone-related protein promotes epithelial-mesenchymal transition.

    Science.gov (United States)

    Ardura, Juan Antonio; Rayego-Mateos, Sandra; Rámila, David; Ruiz-Ortega, Marta; Esbrit, Pedro

    2010-02-01

    Epithelial-mesenchymal transition (EMT) is an important process that contributes to renal fibrogenesis. TGF-beta1 and EGF stimulate EMT. Recent studies suggested that parathyroid hormone-related protein (PTHrP) promotes fibrogenesis in the damaged kidney, apparently dependent on its interaction with vascular endothelial growth factor (VEGF), but whether it also interacts with TGF-beta and EGF to modulate EMT is unknown. Here, PTHrP(1-36) increased TGF-beta1 in cultured tubuloepithelial cells and TGF-beta blockade inhibited PTHrP-induced EMT-related changes, including upregulation of alpha-smooth muscle actin and integrin-linked kinase, nuclear translocation of Snail, and downregulation of E-cadherin and zonula occludens-1. PTHrP(1-36) also induced EGF receptor (EGFR) activation; inhibition of protein kinase C and metalloproteases abrogated this activation. Inhibition of EGFR activation abolished these EMT-related changes, the activation of ERK1/2, and upregulation of TGF-beta1 and VEGF by PTHrP(1-36). Moreover, inhibition of ERK1/2 blocked EMT induced by either PTHrP(1-36), TGF-beta1, EGF, or VEGF. In vivo, obstruction of mouse kidneys led to changes consistent with EMT and upregulation of TGF-beta1 mRNA, p-EGFR protein, and PTHrP. Taken together, these data suggest that PTHrP, TGF-beta, EGF, and VEGF might cooperate through activation of ERK1/2 to induce EMT in renal tubuloepithelial cells.

  13. Parathyroid Hormone–Related Protein Promotes Epithelial–Mesenchymal Transition

    Science.gov (United States)

    Ardura, Juan Antonio; Rayego-Mateos, Sandra; Rámila, David; Ruiz-Ortega, Marta

    2010-01-01

    Epithelial–mesenchymal transition (EMT) is an important process that contributes to renal fibrogenesis. TGF-β1 and EGF stimulate EMT. Recent studies suggested that parathyroid hormone–related protein (PTHrP) promotes fibrogenesis in the damaged kidney, apparently dependent on its interaction with vascular endothelial growth factor (VEGF), but whether it also interacts with TGF-β and EGF to modulate EMT is unknown. Here, PTHrP(1-36) increased TGF-β1 in cultured tubuloepithelial cells and TGF-β blockade inhibited PTHrP-induced EMT-related changes, including upregulation of α-smooth muscle actin and integrin-linked kinase, nuclear translocation of Snail, and downregulation of E-cadherin and zonula occludens-1. PTHrP(1-36) also induced EGF receptor (EGFR) activation; inhibition of protein kinase C and metalloproteases abrogated this activation. Inhibition of EGFR activation abolished these EMT-related changes, the activation of ERK1/2, and upregulation of TGF-β1 and VEGF by PTHrP(1-36). Moreover, inhibition of ERK1/2 blocked EMT induced by either PTHrP(1-36), TGF-β1, EGF, or VEGF. In vivo, obstruction of mouse kidneys led to changes consistent with EMT and upregulation of TGF-β1 mRNA, p-EGFR protein, and PTHrP. Taken together, these data suggest that PTHrP, TGF-β, EGF, and VEGF might cooperate through activation of ERK1/2 to induce EMT in renal tubuloepithelial cells. PMID:19959711

  14. Protein interactions among Fe65, the low-density lipoprotein receptor-related protein, and the amyloid precursor protein.

    Science.gov (United States)

    Mulvihill, Melinda M; Guttman, Miklos; Komives, Elizabeth A

    2011-07-19

    The adapter protein Fe65 has been proposed to be the link between the intracellular domains of the amyloid precursor protein, APP (AICD), and the low-density lipoprotein receptor-related protein (LRP-CT). Functional linkage between these two proteins has been established, and mutations within LRP-CT affect the amount of Aβ produced from APP. Previous work showed that AICD binds to protein interaction domain 2 (PID2) of Fe65. Although the structure of PID1 was determined recently, all attempts to demonstrate LRP-CT binding to this domain failed. We used biophysical experiments and binding studies to investigate the binding among these three proteins. Full-length Fe65 bound more weakly to AICD than did N-terminally truncated forms; however, the intramolecular domain-domain interactions that had been proposed to inhibit binding could not be observed using amide H-D exchange. Surprisingly, when LRP-CT is phosphorylated at Tyr4507, it bound to Fe65 PID1 despite the fact that this domain belongs to the Dab-like subclass of PIDs that are not supposed to be phosphorylation-dependent. Mutation of a critical arginine abolished binding, providing further proof of the phosphorylation dependence. Fe65 PID1 thus provides a link between the Dab-like class and the IRS-like class of PIDs and is the first Dab-like family member to show phosphorylation-dependent binding.

  15. Importance of detecting multidrug resistance proteins in acute leukemia prognosis and therapy.

    Science.gov (United States)

    de Moraes, Ana Carolina Rabello; Maranho, Caroline Klein; Rauber, Gabriela Schneider; Santos-Silva, Maria Cláudia

    2013-01-01

    Multidrug resistance (MDR) is a multifactorial phenomenon and the role of these proteins in generating the MDR phenotype is controversial. With this in mind, this review compiled the current data on the role of ABCB1, ABCC1, and LRP proteins in the prognosis of hematologic neoplasms and their influence on the choice of therapy. Literature showed that the detection of these proteins, mainly ABCB1, is important in the AL prognosis. However, there is controversy regarding the methodology used for their detection. In summary, the expression and activity profiles of ABCB1, ABCC1, and LRP, proteins capable of promoting the efflux of a variety of chemotherapeutic agents from the cell cytoplasm represent one of the greatest causes of failure in AL treatment.

  16. Protein Profiles Associated with Anoikis Resistance of Metastatic MDA-MB-231 Breast Cancer Cells.

    Science.gov (United States)

    Akekawatchai, Chareeporn; Roytrakul, Sittiruk; Kittisenachai, Suthathip; Isarankura-Na-Ayudhya, Patcharee; Jitrapakdee, Sarawut

    2016-01-01

    Resistance to anoikis, a cell-detachment induced apoptosis, is one of the malignant phenotypes which support tumor metastasis. Molecular mechanisms underlying the establishment of this phenotype require further investigation. This study aimed at exploring protein expression profiles associated with anoikis resistance of a metastatic breast cancer cell. Cell survival of suspension cultures of non-metastatic MCF-7 and metastatic MDA-MB-231 cells were compared with their adherent cultures. Trypan blue exclusion assays demonstrated a significantly higher percentage of viable cells in MDA-MB-231 than MCF-7 cell cultures, consistent with analysis of annexin V-7-AAD stained cells indicating that MDA-MB-231 possess anti-apoptotic ability 1.7 fold higher than MCF-7 cells. GeLC-MS/MS analysis of protein lysates of MDA-MB-231 and MCF-7 cells grown under both culture conditions identified 925 proteins which are differentially expressed, 54 of which were expressed only in suspended and adherent MDA-MB-231 but not in MCF-7 cells. These proteins have been implicated in various cellular processes, including DNA replication and repair, transcription, translation, protein modification, cytoskeleton, transport and cell signaling. Analysis based on the STITCH database predicted the interaction of phospholipases, PLC and PLD, and 14-3-3 beta/alpha, YWHAB, with the intrinsic and extrinsic apoptotic signaling network, suggesting putative roles in controlling anti-anoikis ability. MDA-MB-231 cells grown in the presence of inhibitors of phospholipase C, U73122, and phospholipase D, FIPI, demonstrated reduced ability to survive in suspension culture, indicating functional roles of PLC and PLD in the process of anti-anoikis. Our study identified intracellular mediators potentially associated with establishment of anoikis resistance of metastatic cells. These proteins require further clarification as prognostic and therapeutic targets for advanced breast cancer.

  17. Sedentary lifestyle and its relation to cardiovascular risk factors, insulin resistance and inflammatory profile.

    Science.gov (United States)

    León-Latre, Montserrat; Moreno-Franco, Belén; Andrés-Esteban, Eva M; Ledesma, Marta; Laclaustra, Martín; Alcalde, Víctor; Peñalvo, José L; Ordovás, José M; Casasnovas, José A

    2014-06-01

    To analyze the association between sitting time and biomarkers of insulin resistance and inflammation in a sample of healthy male workers. Cross-sectional study carried out in a sample of 929 volunteers belonging to the Aragon Workers' Health Study cohort. Sociodemographic, anthropometric, pharmacological and laboratory data were collected: lipids-total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, apolipoproteins A-1 and B-100, lipoprotein (a)-, insulin resistance-glucose, glycated hemoglobin, homeostasis model assessment of insulin resistance, insulin, and triglyceride/high-density lipoprotein cholesterol ratio-, and inflammatory profile-C-reactive protein and leukocytes. Information on sitting time and physical activity was assessed using a questionnaire. Sedentary behavior was analyzed in terms of prevalences and medians, according to tertiles, using a multivariate model (crude and adjusted linear regression) with biomarkers of inflammation and insulin resistance. The most sedentary individuals had higher body mass index, greater waist circumference, and higher systolic blood pressure, with a significant upward trend in each tertile. Likewise, they had a worse lipid profile with a higher C-reactive protein level, homeostasis model assessment of insulin resistance index, triglyceride/high-density lipoprotein cholesterol ratio, and insulin concentration. In the multivariate analysis, we observed a significant association between the latter parameters and sitting time in hours (log C-reactive protein [β = 0.07], log homeostasis model assessment of insulin resistance index [β = 0.05], triglyceride/high-density lipoprotein cholesterol ratio [β = 0.23], and insulin [β = 0.44]), which remained after adjustment for metabolic equivalents-h/week. Workers who spend more time sitting show a worse inflammatory and insulin resistance profile independently of the physical activity performed. Copyright © 2013

  18. Expression of Multidrug Resistance-Associated Markers, Their Relation to Quantitative Pathologic Tumour Characteristics and Prognosis in Advanced Ovarian Cancer

    Directory of Open Access Journals (Sweden)

    Mariël Brinkhuis

    2002-01-01

    Full Text Available Mean nuclear area has been consistently shown by different researchers to be a strong and independent prognostic factor in advanced ovarian carcinoma. However, the biological background of the prognostic value of nuclear area remains unclear. Others have found that the multidrug‐resistance (MDR related protein LRP has strong prognostic value. In the present study we have analysed whether the mean nuclear area and LRP are related in tumour tissue of the ovary obtained at the debulking operation before the administration of chemotherapy in 40 patients. The mitotic activity index, volume percentage epithelium, standard deviation of nuclear area and the other MDR‐related proteins P‐glycoprotein (JSB‐1, MRK‐16 and MRP have been investigated additionally for correlations and prognostic value. No correlations were found between the morphometrical features and MDR‐related proteins. Mean nuclear area tended to be larger in LRP positive tumours, but the correlation was not significant. In multivariate analysis LRP‐protein expression and mean nuclear area had independent prognostic value. Further studies are required to elucidate the biological background of the strong prognostic value of mean nuclear area in advanced ovarian cancer.

  19. Glyphosate-Resistant Parthenium hysterophorus in the Caribbean Islands: Non Target Site Resistance and Target Site Resistance in Relation to Resistance Levels

    Science.gov (United States)

    Bracamonte, Enzo; Fernández-Moreno, Pablo T.; Barro, Francisco; De Prado, Rafael

    2016-01-01

    Glyphosate has been the most intensely herbicide used worldwide for decades, and continues to be a single tool for controlling weeds in woody crops. However, the adoption of this herbicide in a wide range of culture systems has led to the emergence of resistant weeds. Glyphosate has been widely used primarily on citrus in the Caribbean area, but a study of resistance in the Caribbean islands of Cuba and the Dominican Republic has never been carried out. Unfortunately, Parthenium hysterophorus has developed glyphosate-resistance in both islands, independently. The resistance level and mechanisms of different P. hysterophorus accessions (three collected in Cuba (Cu-R) and four collected in the Dominican Republic (Do-R) have been studied under greenhouse and laboratory conditions. In in vivo assays (glyphosate dose causing 50% reduction in above-ground vegetative biomass and survival), the resistance factor levels showed susceptible accessions (Cu-S ≥ Do-S), low-resistance accessions (Cu-R3 resistance accessions (Do-R3 resistance accessions (Do-R1 resistance factor levels were similar to those found in the shikimic acid accumulation at 1000 μM of glyphosate (Cu-R1 ≥ Do-R1 > Do-R2 > Cu-R2 > Do-R3 > Do-R4 > Cu-R3 >> Cu-S ≥ Do-S). Glyphosate was degraded to aminomethylphosphonic acid, glyoxylate and sarcosine by >88% in resistant accessions except in Cu-R3 and Do-R4 resistant accessions (51.12 and 44.21, respectively), whereas a little glyphosate (resistance levels in P. hysterophorus accessions. One amino acid substitution was found at position 106 in EPSPS, consisting of a proline to serine change in Cu-R1, Do-R1 Do-R2. The above-mentioned results indicate that high resistance values are determined by the number of defense mechanisms (target-site and non-target-site resistance) possessed by the different P. hysterophorus accessions, concurrently. PMID:27999586

  20. Acute post-exercise myofibrillar protein synthesis is not correlated with resistance training-induced muscle hypertrophy in young men.

    Science.gov (United States)

    Mitchell, Cameron J; Churchward-Venne, Tyler A; Parise, Gianni; Bellamy, Leeann; Baker, Steven K; Smith, Kenneth; Atherton, Philip J; Phillips, Stuart M

    2014-01-01

    Muscle hypertrophy following resistance training (RT) involves activation of myofibrillar protein synthesis (MPS) to expand the myofibrillar protein pool. The degree of hypertrophy following RT is, however, highly variable and thus we sought to determine the relationship between the acute activation of MPS and RT-induced hypertrophy. We measured MPS and signalling protein activation after the first session of resistance exercise (RE) in untrained men (n = 23) and then examined the relation between MPS with magnetic resonance image determined hypertrophy. To measure MPS, young men (24±1 yr; body mass index  = 26.4±0.9 kg•m²) underwent a primed constant infusion of L-[ring-¹³C₆] phenylalanine to measure MPS at rest, and acutely following their first bout of RE prior to 16 wk of RT. Rates of MPS were increased 235±38% (Pmuscle volume and acute rates of MPS measured over 1-3 h (r = 0.02), 3-6 h (r = 0.16) or the aggregate 1-6 h post-exercise period (r = 0.10). Hypertrophy after chronic RT was correlated (r = 0.42, P = 0.05) with phosphorylation of 4E-BP1(Thr37/46) at 1 hour post RE. We conclude that acute measures of MPS following an initial exposure to RE in novices are not correlated with muscle hypertrophy following chronic RT.

  1. A Peroxiredoxin Promotes H2O2 Signaling and Oxidative Stress Resistance by Oxidizing a Thioredoxin Family Protein

    Directory of Open Access Journals (Sweden)

    Jonathon D. Brown

    2013-12-01

    Full Text Available H2O2 can cause oxidative damage associated with age-related diseases such as diabetes and cancer but is also used to initiate diverse responses, including increased antioxidant gene expression. Despite significant interest, H2O2-signaling mechanisms remain poorly understood. Here, we present a mechanism for the propagation of an H2O2 signal that is vital for the adaptation of the model yeast, Schizosaccharomyces pombe, to oxidative stress. Peroxiredoxins are abundant peroxidases with conserved antiaging and anticancer activities. Remarkably, we find that the only essential function for the thioredoxin peroxidase activity of the Prx Tpx1(hPrx1/2 in resistance to H2O2 is to inhibit a conserved thioredoxin family protein Txl1(hTxnl1/TRP32. Thioredoxins regulate many enzymes and signaling proteins. Thus, our discovery that a Prx amplifies an H2O2 signal by driving the oxidation of a thioredoxin-like protein has important implications, both for Prx function in oxidative stress resistance and for responses to H2O2.

  2. Biological improvement of radiation resistance

    Energy Technology Data Exchange (ETDEWEB)

    Chun, K. J.; Lee, Y. K.; Kim, J. S.; Kim, J. K.; Lee, S. J

    2000-08-01

    To investigate the mechanisms of gene action related to the radiation resistance in microorganisms could be essentially helpful for the development of radiation protectants and hormeric effects of low dose radiation. This book described isolation of radiation-resistant microorganisms, induction of radiation-resistant and functionally improved mutants by gamma-ray radiation, cloning and analysis of the radiation resistance related genes and analysis of the expressed proteins of the radiation resistant related genes.

  3. Establishment of a paclitaxel resistant human breast cancer cell strain (MCF-7/Taxol) and intracellular paclitaxel binding protein analysis.

    Science.gov (United States)

    Zuo, K-Q; Zhang, X-P; Zou, J; Li, D; Lv, Z-W

    2010-01-01

    Multidrug resistance of tumours is one of the most important factors that leads to chemotherapy failure. A multidrug-resistant breast cancer cell line, MCF-7/Taxol, was established from the drug-sensitive parent cell line MCF-7. The biological properties of MCF-7/Taxol, including its drug resistance profile and profile of paclitaxel binding proteins, were analysed and compared with the parent cell line. A number of paclitaxel binding proteins were present in MCF-7 cells but absent from MCF-7/Taxol cells, namely heat shock protein 90, actinin and dermcidin precursor. The identification of differential paclitaxel binding proteins between the multidrug-resistant MCF-7/Taxol cell line and the parent drug-sensitive cell line MCF-7 provides insight into possible mechanisms involved in resistance to these chemotherapy drugs.

  4. Mutations in the bacterial ribosomal protein l3 and their association with antibiotic resistance

    DEFF Research Database (Denmark)

    Klitgaard, Rasmus N; Ntokou, Eleni; Nørgaard, Katrine

    2015-01-01

    Different groups of antibiotics bind to the peptidyl transferase center (PTC) in the large subunit of the bacterial ribosome. Resistance to these groups of antibiotics has often been linked with mutations or methylations of the 23S rRNA. In recent years, there has been a rise in the number...... of studies where mutations have been found in the ribosomal protein L3 in bacterial strains resistant to PTC-targeting antibiotics but there is often no evidence that these mutations actually confer antibiotic resistance. In this study, a plasmid exchange system was used to replace plasmid-carried wild...... background. Ten plasmid-carried mutated L3 genes were constructed, and their effect on growth and antibiotic susceptibility was investigated. Additionally, computational modeling of the impact of L3 mutations in E. coli was used to assess changes in 50S structure and antibiotic binding. All mutations...

  5. Posttranslational modification of autophagy-related proteins in macroautophagy.

    Science.gov (United States)

    Xie, Yangchun; Kang, Rui; Sun, Xiaofang; Zhong, Meizuo; Huang, Jin; Klionsky, Daniel J; Tang, Daolin

    2015-01-01

    Macroautophagy is an intracellular catabolic process involved in the formation of multiple membrane structures ranging from phagophores to autophagosomes and autolysosomes. Dysfunction of macroautophagy is implicated in both physiological and pathological conditions. To date, 38 autophagy-related (ATG) genes have been identified as controlling these complicated membrane dynamics during macroautophagy in yeast; approximately half of these genes are clearly conserved up to human, and there are additional genes whose products function in autophagy in higher eukaryotes that are not found in yeast. The function of the ATG proteins, in particular their ability to interact with a number of macroautophagic regulators, is modulated by posttranslational modifications (PTMs) such as phosphorylation, glycosylation, ubiquitination, acetylation, lipidation, and proteolysis. In this review, we summarize our current knowledge of the role of ATG protein PTMs and their functional relevance in macroautophagy. Unraveling how these PTMs regulate ATG protein function during macroautophagy will not only reveal fundamental mechanistic insights into the regulatory process, but also provide new therapeutic targets for the treatment of autophagy-associated diseases.

  6. Macrophage replication screen identifies a novel Francisella hydroperoxide resistance protein involved in virulence.

    Directory of Open Access Journals (Sweden)

    Anna C Llewellyn

    Full Text Available Francisella tularensis is a gram-negative facultative intracellular pathogen and the causative agent of tularemia. Recently, genome-wide screens have identified Francisella genes required for virulence in mice. However, the mechanisms by which most of the corresponding proteins contribute to pathogenesis are still largely unknown. To further elucidate the roles of these virulence determinants in Francisella pathogenesis, we tested whether each gene was required for replication of the model pathogen F. novicida within macrophages, an important virulence trait. Fifty-three of the 224 genes tested were involved in intracellular replication, including many of those within the Francisella pathogenicity island (FPI, validating our results. Interestingly, over one third of the genes identified are annotated as hypothetical, indicating that F. novicida likely utilizes novel virulence factors for intracellular replication. To further characterize these virulence determinants, we selected two hypothetical genes to study in more detail. As predicted by our screen, deletion mutants of FTN_0096 and FTN_1133 were attenuated for replication in macrophages. The mutants displayed differing levels of attenuation in vivo, with the FTN_1133 mutant being the most attenuated. FTN_1133 has sequence similarity to the organic hydroperoxide resistance protein Ohr, an enzyme involved in the bacterial response to oxidative stress. We show that FTN_1133 is required for F. novicida resistance to, and degradation of, organic hydroperoxides as well as resistance to the action of the NADPH oxidase both in macrophages and mice. Furthermore, we demonstrate that F. holarctica LVS, a strain derived from a highly virulent human pathogenic species of Francisella, also requires this protein for organic hydroperoxide resistance as well as replication in macrophages and mice. This study expands our knowledge of Francisella's largely uncharacterized intracellular lifecycle and

  7. A systemic resistance inducing antiviral protein with N-glycosidase activity from Bougainvillea xbuttiana leaves.

    Science.gov (United States)

    Narwal, S; Balasubrahmanyam, A; Sadhna, P; Kapoor, H; Lodha, M L

    2001-06-01

    An antiviral protein from Bougainvillea xbuttiana leaves induced systemic resistance in host plants N. glutinosa and Cyamopsis tetragonoloba against TMV and SRV, respectively which was reversed by actinomycin D, when applied immediately or shortly after antiviral protein treatment. When the inhibitor was applied to the host plant leaves post inoculation, it was effective if applied upto 4 h after virus infection. It also delayed the expression of symptoms in systemic hosts of TMV. The inhibitor showed characteristic N-glycosidase activity on 25S rRNA of tobacco ribosomes, suggesting that it could also be interfering with virus multiplication through ribosome-inactivation process.

  8. Metabolic responses to high protein diet in Korean elite bodybuilders with high-intensity resistance exercise

    Directory of Open Access Journals (Sweden)

    Choue Ryowon

    2011-07-01

    Full Text Available Abstract Background High protein diet has been known to cause metabolic acidosis, which is manifested by increased urinary excretion of nitrogen and calcium. Bodybuilders habitually consumed excessive dietary protein over the amounts recommended for them to promote muscle mass accretion. This study investigated the metabolic response to high protein consumption in the elite bodybuilders. Methods Eight elite Korean bodybuilders within the age from 18 to 25, mean age 21.5 ± 2.6. For data collection, anthropometry, blood and urinary analysis, and dietary assessment were conducted. Results They consumed large amounts of protein (4.3 ± 1.2 g/kg BW/day and calories (5,621.7 ± 1,354.7 kcal/day, as well as more than the recommended amounts of vitamins and minerals, including potassium and calcium. Serum creatinine (1.3 ± 0.1 mg/dl and potassium (5.9 ± 0.8 mmol/L, and urinary urea nitrogen (24.7 ± 9.5 mg/dl and creatinine (2.3 ± 0.7 mg/dl were observed to be higher than the normal reference ranges. Urinary calcium (0.3 ± 0.1 mg/dl, and phosphorus (1.3 ± 0.4 mg/dl were on the border of upper limit of the reference range and the urine pH was in normal range. Conclusions Increased urinary excretion of urea nitrogen and creatinine might be due to the high rates of protein metabolism that follow high protein intake and muscle turnover. The obvious evidence of metabolic acidosis in response to high protein diet in the subjects with high potassium intake and intensive resistance exercise were not shown in this study results. However, this study implied that resistance exercise with adequate mineral supplementation, such as potassium and calcium, could reduce or offset the negative effects of protein-generated metabolic changes. This study provides preliminary information of metabolic response to high protein intake in bodybuilders who engaged in high-intensity resistance exercise. Further studies will be needed to determine the effects of the intensity

  9. Chromosome engineering techniques for targeted introgression of rust resistance from wild wheat relatives

    Science.gov (United States)

    Hexaploid wheat has relatively narrow genetic diversity due to its evolution and domestication processes compared to its wild relatives that often carry agronomically important traits including resistance to biotic and abiotic stresses. Many genes have been introgressed into wheat from wild relative...

  10. Characterisation of the protein corona using tunable resistive pulse sensing: determining the change and distribution of a particle's surface charge.

    Science.gov (United States)

    Blundell, Emma L C J; Healey, Matthew J; Holton, Elizabeth; Sivakumaran, Muttuswamy; Manstana, Sarabjit; Platt, Mark

    2016-08-01

    The zeta potential of the protein corona around carboxyl particles has been measured using tunable resistive pulse sensing (TRPS). A simple and rapid assay for characterising zeta potentials within buffer, serum and plasma is presented monitoring the change, magnitude and distribution of proteins on the particle surface. First, we measure the change in zeta potential of carboxyl-functionalised nanoparticles in solutions that contain biologically relevant concentrations of individual proteins, typically constituted in plasma and serum, and observe a significant difference in distributions and zeta values between room temperature and 37 °C assays. The effect is protein dependent, and the largest difference between the two temperatures is recorded for the γ-globulin protein where the mean zeta potential changes from -16.7 to -9.0 mV for 25 and 37 °C, respectively. This method is further applied to monitor particles placed into serum and/or plasma. A temperature-dependent change is again observed with serum showing a 4.9 mV difference in zeta potential between samples incubated at 25 and 37 °C; this shift was larger than that observed for samples in plasma (0.4 mV). Finally, we monitor the kinetics of the corona reorientation for particles initially placed into serum and then adding 5 % (V/V) plasma. The technology presented offers an interesting insight into protein corona structure and kinetics of formation measured in biologically relevant solutions, i.e. high protein, high salt levels, and its particle-by-particle analysis gives a measure of the distribution of particle zeta potential that may offer a better understanding of the behaviour of nanoparticles in solution. Graphical Abstract The relative velocity of a nanoparticle as it traverses a nanopore can be used to determine its zeta potential. Monitoring the changes in translocation speeds can therefore be used to follow changes to the surface chemistry/composition of 210 nm particles that were placed

  11. Glutathione depletion regulates both extrinsic and intrinsic apoptotic signaling cascades independent from multidrug resistance protein 1

    OpenAIRE

    2014-01-01

    Glutathione (GSH) depletion is an important hallmark of apoptosis. We previously demonstrated that GSH depletion, by its efflux, regulates apoptosis by modulation of executioner caspase activity. However, both the molecular identity of the GSH transporter(s) involved and the signaling cascades regulating GSH loss remain obscure. We sought to determine the role of multidrug resistance protein 1 (MRP1) in GSH depletion and its regulatory role on extrinsic and intrinsic pathways of apoptosis. In...

  12. Modulation of function of multidrug resistance associated-proteins by Kaempferia parviflora extracts and their components

    OpenAIRE

    Patanasethanont, Denpong; NAGAI, Junya; Matsuura, Chie; Fukui, Kyoko; Sutthanut, Khaetthareeya; Sripanidkulchai, Bung-Orn; Yumoto, Ryoko; Takano, Mikihisa

    2007-01-01

    In this study, the effects of extracts and flavone derivatives from the rhizome of Kaempferia parviflora on multidrug resistance associated-proteins (MRP)-mediated transport in A549 cells were examined. The cells employed express MRP1 and MRP2, but not P-glycoprotein. The cellular accumulation of calcein, an MRP substrate, was significantly increased by various MRP inhibitors without being affected by verapamil, a typical P-glycoprotein inhibitor. Ethanol and aqueous extracts from Kaempferia ...

  13. Whey protein consumption after resistance exercise reduces energy intake at a post-exercise meal.

    Science.gov (United States)

    Monteyne, Alistair; Martin, Alex; Jackson, Liam; Corrigan, Nick; Stringer, Ellen; Newey, Jack; Rumbold, Penny L S; Stevenson, Emma J; James, Lewis J

    2016-11-10

    Protein consumption after resistance exercise potentiates muscle protein synthesis, but its effects on subsequent appetite in this context are unknown. This study examined appetite and energy intake following consumption of protein- and carbohydrate-containing drinks after resistance exercise. After familiarisation, 15 resistance training males (age 21 ± 1 years, body mass 78.0 ± 11.9 kg, stature 1.78 ± 0.07 m) completed two randomised, double-blind trials, consisting of lower-body resistance exercise, followed by consumption of a whey protein (PRO 23.9 ± 3.6 g protein) or dextrose (CHO 26.5 ± 3.8 g carbohydrate) drink in the 5 min post-exercise. An ad libitum meal was served 60 min later, with subjective appetite measured throughout. Drinks were flavoured and matched for energy content and volume. The PRO drink provided 0.3 g/kg body mass protein. Ad libitum energy intake (PRO 3742 ± 994 kJ; CHO 4172 ± 1132 kJ; P = 0.007) and mean eating rate (PRO 339 ± 102 kJ/min; CHO 405 ± 154 kJ/min; P = 0.009) were lower during PRO. The change in eating rate was associated with the change in energy intake (R = 0.661, P = 0.007). No interaction effects were observed for subjective measures of appetite. The PRO drink was perceived as creamier and thicker, and less pleasant, sweet and refreshing (P consumption after resistance exercise reduces subsequent energy intake, and this might be partially mediated by a reduced eating rate. Whilst this reduced energy intake is unlikely to impair hypertrophy, it may be of value in supporting an energy deficit for weight loss.

  14. Evaluation of iTRAQ and SWATH-MS for the Quantification of Proteins Associated with Insulin Resistance in Human Duodenal Biopsy Samples.

    Science.gov (United States)

    Bourassa, Sylvie; Fournier, Frédéric; Nehmé, Benjamin; Kelly, Isabelle; Tremblay, André; Lemelin, Valéry; Lamarche, Benoit; Couture, Patrick; Droit, Arnaud

    2015-01-01

    Insulin resistance (IR) is associated with increased production of triglyceride-rich lipoproteins of intestinal origin. In order to assess whether insulin resistance affects the proteins involved in lipid metabolism, we used two mass spectrometry based quantitative proteomics techniques to compare the intestinal proteome of 14 IR patients to that of 15 insulin sensitive (IS) control patients matched for age and waist circumference. A total of 3886 proteins were identified by the iTRAQ (Isobaric Tags for Relative and Absolute Quantitation) mass spectrometry approach and 2290 by the SWATH-MS strategy (Serial Window Acquisition of Theoretical Spectra). Using these two methods, 208 common proteins were identified with a confidence corresponding to FDR < 1%, and quantified with p-value < 0.05. The quantification of those 208 proteins has a Pearson correlation coefficient (r2) of 0.728 across the two techniques. Gene Ontology analyses of the differentially expressed proteins revealed that annotations related to lipid metabolic process and oxidation reduction process are overly represented in the set of under-expressed proteins in IR subjects. Furthermore, both methods quantified proteins of relevance to IR. These data also showed that SWATH-MS is a promising and compelling alternative to iTRAQ for protein quantitation of complex mixtures.

  15. Protein supplementation augments the adaptive response of skeletal muscle to resistance-type exercise training: a meta-analysis

    NARCIS (Netherlands)

    Cermak, N.M.; Res, P.T.; Groot, de C.P.G.M.; Saris, W.H.M.; Loon, van L.J.C.

    2012-01-01

    Background: Protein ingestion after a single bout of resistance-type exercise stimulates net muscle protein accretion during acute postexercise recovery. Consequently, it is generally accepted that protein supplementation is required to maximize the adaptive response of the skeletal muscle to prolon

  16. Protein supplementation augments the adaptive response of skeletal muscle to resistance-type exercise training: a meta-analysis

    NARCIS (Netherlands)

    Cermak, N.M.; Res, P.T.; Groot, de C.P.G.M.; Saris, W.H.M.; Loon, van L.J.C.

    2012-01-01

    Background: Protein ingestion after a single bout of resistance-type exercise stimulates net muscle protein accretion during acute postexercise recovery. Consequently, it is generally accepted that protein supplementation is required to maximize the adaptive response of the skeletal muscle to

  17. [Structure analysis of disease-related proteins using vibrational spectroscopy].

    Science.gov (United States)

    Hiramatsu, Hirotsugu

    2014-01-01

    Analyses of the structure and properties of identified pathogenic proteins are important for elucidating the molecular basis of diseases and in drug discovery research. Vibrational spectroscopy has advantages over other techniques in terms of sensitivity of detection of structural changes. Spectral analysis, however, is complicated because the spectrum involves a substantial amount of information. This article includes examples of structural analysis of disease-related proteins using vibrational spectroscopy in combination with additional techniques that facilitate data acquisition and analysis. Residue-specific conformation analysis of an amyloid fibril was conducted using IR absorption spectroscopy in combination with (13)C-isotope labeling, linear dichroism measurement, and analysis of amide I band features. We reveal a pH-dependent property of the interacting segment of an amyloidogenic protein, β2-microglobulin, which causes dialysis-related amyloidosis. We also reveal the molecular mechanisms underlying pH-dependent sugar-binding activity of human galectin-1, which is involved in cell adhesion, using spectroscopic techniques including UV resonance Raman spectroscopy. The decreased activity at acidic pH was attributed to a conformational change in the sugar-binding pocket caused by protonation of His52 (pKa 6.3) and the cation-π interaction between Trp68 and the protonated His44 (pKa 5.7). In addition, we show that the peak positions of the Raman bands of the C4=C5 stretching mode at approximately 1600 cm(-1) and the Nπ-C2-Nτ bending mode at approximately 1405 cm(-1) serve as markers of the His side-chain structure. The Raman signal was enhanced 12 fold using a vertical flow apparatus.

  18. Resistance in tomato and wild relatives to crown and root rot caused by Phytophthora capsici.

    Science.gov (United States)

    Quesada-Ocampo, L M; Hausbeck, M K

    2010-06-01

    Phytophthora capsici causes root, crown, and fruit rot of tomato, a major vegetable crop grown worldwide. The objective of this study was to screen tomato cultivars and wild relatives of tomato for resistance to P. capsici. Four P. capsici isolates were individually used to inoculate 6-week-old seedlings (1 g of P. capsici-infested millet seed per 10 g of soilless medium) of 42 tomato cultivars and wild relatives of tomato in a greenhouse. Plants were evaluated daily for wilting and death. All P. capsici isolates tested caused disease in seedlings but some isolates were more pathogenic than others. A wild relative of cultivated tomato, Solanum habrochaites accession LA407, was resistant to all P. capsici isolates tested. Moderate resistance to all isolates was identified in the host genotypes Ha7998, Fla7600, Jolly Elf, and Talladega. P. capsici was frequently recovered from root and crown tissue of symptomatic inoculated seedlings but not from leaf tissue or asymptomatic or control plants. The phenotype of the recovered isolate matched the phenotype of the inoculum. Pathogen presence was confirmed in resistant and moderately resistant tomato genotypes by species-specific polymerase chain reaction of DNA from infected crown and root tissue. Amplified fragment length polymorphisms of tomato genotypes showed a lack of correlation between genetic clusters and susceptibility to P. capsici, indicating that resistance is distributed in several tomato lineages. The results of this study create a baseline for future development of tomato cultivars resistant to P. capsici.

  19. Crystallization and preliminary X-ray diffraction analyses of the TIR domains of three TIR-NB-LRR proteins that are involved in disease resistance in Arabidopsis thaliana.

    Science.gov (United States)

    Wan, Li; Zhang, Xiaoxiao; Williams, Simon J; Ve, Thomas; Bernoux, Maud; Sohn, Kee Hoon; Jones, Jonathan D G; Dodds, Peter N; Kobe, Bostjan

    2013-11-01

    The Toll/interleukin-1 receptor (TIR) domain is a protein-protein interaction domain that is found in both animal and plant immune receptors. The N-terminal TIR domain from the nucleotide-binding (NB)-leucine-rich repeat (LRR) class of plant disease-resistance (R) proteins has been shown to play an important role in defence signalling. Recently, the crystal structure of the TIR domain from flax R protein L6 was determined and this structure, combined with functional studies, demonstrated that TIR-domain homodimerization is a requirement for function of the R protein L6. To advance the molecular understanding of the function of TIR domains in R-protein signalling, the protein expression, purification, crystallization and X-ray diffraction analyses of the TIR domains of the Arabidopsis thaliana R proteins RPS4 (resistance to Pseudomonas syringae 4) and RRS1 (resistance to Ralstonia solanacearum 1) and the resistance-like protein SNC1 (suppressor of npr1-1, constitutive 1) are reported here. RPS4 and RRS1 function cooperatively as a dual resistance-protein system that prevents infection by three distinct pathogens. SNC1 is implicated in resistance pathways in Arabidopsis and is believed to be involved in transcriptional regulation through its interaction with the transcriptional corepressor TPR1 (Topless-related 1). The TIR domains of all three proteins have successfully been expressed and purified as soluble proteins in Escherichia coli. Plate-like crystals of the RPS4 TIR domain were obtained using PEG 3350 as a precipitant; they diffracted X-rays to 2.05 Å resolution, had the symmetry of space group P1 and analysis of the Matthews coefficient suggested that there were four molecules per asymmetric unit. Tetragonal crystals of the RRS1 TIR domain were obtained using ammonium sulfate as a precipitant; they diffracted X-rays to 1.75 Å resolution, had the symmetry of space group P4(1)2(1)2 or P4(3)2(1)2 and were most likely to contain one molecule per asymmetric

  20. A preliminary study of genes related to concomitant chemoradiotherapy resistance in advanced uterine cervical squamous cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    AN Ju-sheng; HUANG Man-ni; SONG Yong-mei; LI Nan; WU Ling-ying; ZHAN Qi-min

    2013-01-01

    Background Tumor intrinsic chemoradiotherapy resistance is the primary factor in concomitant chemoradiotherapy failure in advanced uterine cervical squamous cell carcinoma.This study aims to identify a set of genes and molecular pathways related to this condition.Methods Forty patients with uterine cervical squamous cell carcinoma in International Federation of Gynecology and Obstetrics stage lib or IIIb,treated with platinum-based concomitant chemoradiotherapy between May 2007 and December 2012,were enrolled in this trial.Patients included chemoradiotherapy resistant (n=20) and sensitive (n=20) groups.Total RNA was extracted from fresh tumor tissues obtained by biopsy before treatment and microarray analysis was performed to identify genes differentially expressed between the two groups.Results Microarray analysis identified 108 genes differentially expressed between concomitant chemoradiotherapy resistant and sensitive patients.Functional pathway cluster analysis of these genes revealed that DNA damage repair,apoptosis,cell cycle,Map kinase signal transduction,anaerobic glycolysis and glutathione metabolism were the most relevant pathways.Platelet-derived growth factor receptor alpha (PDGFRA) and protein kinase A type 1A (PRKAR1A)were significantly upregulated in the chemoradiosensitive group,while lactate dehydrogenase A (LDHA),bcl2 antagonist/killer 1 (BAK1),bcl2/adenovirus E1B 19 kDa interacting protein 3 (BNIP3),single-strand-selective monofunctional uracilDNA glycosylase 1 (SMUG1),and cyclin-dependent kinase 7 (CDK7) were upregulated in the chemoradiotherapy resistant group.Conclusion We have identified seven genes that are differentially expressed in concomitant chemoradiotherapy resistant and sensitive uterine cervical squamous cell carcinomas,which may represent primary predictors for this condition.

  1. Membrane protein resistance of oligo(ethylene oxide) self-assembled monolayers.

    Science.gov (United States)

    Vaish, Amit; Vanderah, David J; Vierling, Ryan; Crawshaw, Fay; Gallagher, D Travis; Walker, Marlon L

    2014-10-01

    As part of an effort to develop biointerfaces for structure-function studies of integral membrane proteins (IMPs) a series of oligo(ethylene oxide) self-assembled monolayers (OEO-SAMs) were evaluated for their resistance to protein adsorption (RPA) of IMPs on Au and Pt. Spectroscopic ellipsometry (SE) was used to determine SAM thicknesses and compare the RPA of HS(CH2)3O(CH2CH2O)6CH3 (1), HS(CH2)3O(CH2CH2O)6H (2), [HS(CH2)3]2CHO(CH2CH2O)6CH3 (3) and [HS(CH2)3]2CHO(CH2CH2O)6H (4), assembled from water. For both substrates, SAM thicknesses for 1 to 4 were found to be comparable indicating SAMs with similar surface coverages and OEO chain order and packing densities. Fibrinogen (Fb), a soluble plasma protein, and rhodopsin (Rd), an integral membrane G-protein coupled receptor, adsorbed to the SAMs of 1, as expected from previous reports, but not to the hydroxy-terminated SAMs of 2 and 4. The methoxy-terminated SAMs of 3 were resistant to Fb but, surprisingly, not to Rd. The stark difference between the adsorption of Rd to the SAMs of 3 and 4 clearly indicate that a hydroxy-terminus of the OEO chain is essential for high RPA of IMPs. The similar thicknesses and high RPA of the SAMs of 2 and 4 show the conditions of protein resistance (screening the underlying substrate, packing densities, SAM order, and conformational mobility of the OEO chains) defined from previous studies on Au are applicable to Pt. In addition, the SAMs of 4, exhibiting the highest resistance to Fb and Rd, were placed in contact with undiluted fetal bovine serum for 2h. Low protein adsorption (≈12.4ng/cm(2)), obtained under these more challenging conditions, denote a high potential of the SAMs of 4 for various applications requiring the suppression of non-specific protein adsorption.

  2. SynProt: A Comprehensive Database for Proteins of the Detergent-Resistant Synaptic Junctions Fraction

    Directory of Open Access Journals (Sweden)

    Rainer ePielot

    2012-06-01

    Full Text Available Chemical synapses are highly specialized cell-cell contacts for communication between neurons in the CNS characterized by complex and dynamic protein networks at both synaptic membranes. The cytomatrix at the active zone (CAZ organizes the apparatus for the regulated release of transmitters from the presynapse. At the postsynaptic side, the postsynaptic density constitutes the machinery for detection, integration and transduction of the transmitter signal. Both pre- and postsynaptic protein networks represent the molecular substrates for synaptic plasticity. Their function can be altered both by regulating their composition and by post-translational modification of their components. For a comprehensive understanding of synaptic networks the entire ensemble of synaptic proteins has to be considered. To support this, we established a comprehensive database for synaptic junction proteins (SynProt database primarily based on proteomics data obtained from biochemical preparations of detergent-resistant synaptic junctions. The database currently contains 2,788 non-redundant entries of rat, mouse and some human proteins, which mainly have been manually extracted from twelve proteomic studies and annotated for synaptic subcellular localization. Each dataset is completed with manually added information including protein classifiers as well as automatically retrieved and updated information from public databases (UniProt and PubMed. We intend that the database will be used to support modeling of synaptic protein networks and rational experimental design.

  3. Overexpression of uncoupling protein 3 in skeletal muscle protects against fat-induced insulin resistance

    Science.gov (United States)

    Choi, Cheol Soo; Fillmore, Jonathan J.; Kim, Jason K.; Liu, Zhen-Xiang; Kim, Sheene; Collier, Emily F.; Kulkarni, Ameya; Distefano, Alberto; Hwang, Yu-Jin; Kahn, Mario; Chen, Yan; Yu, Chunli; Moore, Irene K.; Reznick, Richard M.; Higashimori, Takamasa; Shulman, Gerald I.

    2007-01-01

    Insulin resistance is a major factor in the pathogenesis of type 2 diabetes and is strongly associated with obesity. Increased concentrations of intracellular fatty acid metabolites have been postulated to interfere with insulin signaling by activation of a serine kinase cascade involving PKCθ in skeletal muscle. Uncoupling protein 3 (UCP3) has been postulated to dissipate the mitochondrial proton gradient and cause metabolic inefficiency. We therefore hypothesized that overexpression of UCP3 in skeletal muscle might protect against fat-induced insulin resistance in muscle by conversion of intramyocellular fat into thermal energy. Wild-type mice fed a high-fat diet were markedly insulin resistant, a result of defects in insulin-stimulated glucose uptake in skeletal muscle and hepatic insulin resistance. Insulin resistance in these tissues was associated with reduced insulin-stimulated insulin receptor substrate 1– (IRS-1–) and IRS-2–associated PI3K activity in muscle and liver, respectively. In contrast, UCP3-overexpressing mice were completely protected against fat-induced defects in insulin signaling and action in these tissues. Furthermore, these changes were associated with a lower membrane-to-cytosolic ratio of diacylglycerol and reduced PKCθ activity in whole-body fat–matched UCP3 transgenic mice. These results suggest that increasing mitochondrial uncoupling in skeletal muscle may be an excellent therapeutic target for type 2 diabetes mellitus. PMID:17571165

  4. Mechanosensitive molecular networks involved in transducing resistance exercise-signals into muscle protein accretion

    Directory of Open Access Journals (Sweden)

    Emil Rindom

    2016-11-01

    Full Text Available Loss of skeletal muscle myofibrillar protein with disease and/or inactivity can severely deteriorate muscle strength and function. Strategies to counteract wasting of muscle myofibrillar protein are therefore desirable and invite for considerations on the potential superiority of specific modes of resistance exercise and/or the adequacy of low load resistance exercise regimens as well as underlying mechanisms. In this regard, delineation of the potentially mechanosensitive molecular mechanisms underlying muscle protein synthesis (MPS, may contribute to understanding on how differentiated resistance exercise can transduce a mechanical signal into stimulation of muscle accretion. Recent findings suggest specific upstream exercise-induced mechano-sensitive myocellular signaling pathways to converge on mammalian target of rapamycin complex 1 (mTORC1, to influence MPS. This may e.g. implicate mechanical activation of signaling through a diacylglycerol kinase (DGKζ-phosphatidic acid (PA axis or implicate integrin deformation to signal through a Focal adhesion kinase (FAK-Tuberous Sclerosis Complex 2TSC2-Ras homolog enriched in brain (Rheb axis. Moreover, since initiation of translation is reliant on mRNA, it is also relevant to consider potentially mechanosensitive signaling pathways involved in muscle myofibrillar gene transcription and whether some of these pathways converge with those affecting mTORC1 activation for MPS. In this regard, recent findings suggest how mechanical stress may implicate integrin deformation and/or actin dynamics to signal through a Ras homolog gene family member A protein (RhoA-striated muscle activator of Rho signaling (STARS axis or how it may implicate deformation of Notch to affect Bone Morphogenetic Protein (BMP signaling through a small mother of decapentaplegic (Smad axis.

  5. Mechanosensitive Molecular Networks Involved in Transducing Resistance Exercise-Signals into Muscle Protein Accretion

    Science.gov (United States)

    Rindom, Emil; Vissing, Kristian

    2016-01-01

    Loss of skeletal muscle myofibrillar protein with disease and/or inactivity can severely deteriorate muscle strength and function. Strategies to counteract wasting of muscle myofibrillar protein are therefore desirable and invite for considerations on the potential superiority of specific modes of resistance exercise and/or the adequacy of low load resistance exercise regimens as well as underlying mechanisms. In this regard, delineation of the potentially mechanosensitive molecular mechanisms underlying muscle protein synthesis (MPS), may contribute to an understanding on how differentiated resistance exercise can transduce a mechanical signal into stimulation of muscle accretion. Recent findings suggest specific upstream exercise-induced mechano-sensitive myocellular signaling pathways to converge on mammalian target of rapamycin complex 1 (mTORC1), to influence MPS. This may e.g. implicate mechanical activation of signaling through a diacylglycerol kinase (DGKζ)-phosphatidic acid (PA) axis or implicate integrin deformation to signal through a Focal adhesion kinase (FAK)-Tuberous Sclerosis Complex 2 (TSC2)-Ras homolog enriched in brain (Rheb) axis. Moreover, since initiation of translation is reliant on mRNA, it is also relevant to consider potentially mechanosensitive signaling pathways involved in muscle myofibrillar gene transcription and whether some of these pathways converge with those affecting mTORC1 activation for MPS. In this regard, recent findings suggest how mechanical stress may implicate integrin deformation and/or actin dynamics to signal through a Ras homolog gene family member A protein (RhoA)-striated muscle activator of Rho signaling (STARS) axis or implicate deformation of Notch to affect Bone Morphogenetic Protein (BMP) signaling through a small mother of decapentaplegic (Smad) axis. PMID:27909410

  6. Mechanosensitive Molecular Networks Involved in Transducing Resistance Exercise-Signals into Muscle Protein Accretion.

    Science.gov (United States)

    Rindom, Emil; Vissing, Kristian

    2016-01-01

    Loss of skeletal muscle myofibrillar protein with disease and/or inactivity can severely deteriorate muscle strength and function. Strategies to counteract wasting of muscle myofibrillar protein are therefore desirable and invite for considerations on the potential superiority of specific modes of resistance exercise and/or the adequacy of low load resistance exercise regimens as well as underlying mechanisms. In this regard, delineation of the potentially mechanosensitive molecular mechanisms underlying muscle protein synthesis (MPS), may contribute to an understanding on how differentiated resistance exercise can transduce a mechanical signal into stimulation of muscle accretion. Recent findings suggest specific upstream exercise-induced mechano-sensitive myocellular signaling pathways to converge on mammalian target of rapamycin complex 1 (mTORC1), to influence MPS. This may e.g. implicate mechanical activation of signaling through a diacylglycerol kinase (DGKζ)-phosphatidic acid (PA) axis or implicate integrin deformation to signal through a Focal adhesion kinase (FAK)-Tuberous Sclerosis Complex 2 (TSC2)-Ras homolog enriched in brain (Rheb) axis. Moreover, since initiation of translation is reliant on mRNA, it is also relevant to consider potentially mechanosensitive signaling pathways involved in muscle myofibrillar gene transcription and whether some of these pathways converge with those affecting mTORC1 activation for MPS. In this regard, recent findings suggest how mechanical stress may implicate integrin deformation and/or actin dynamics to signal through a Ras homolog gene family member A protein (RhoA)-striated muscle activator of Rho signaling (STARS) axis or implicate deformation of Notch to affect Bone Morphogenetic Protein (BMP) signaling through a small mother of decapentaplegic (Smad) axis.

  7. Adaptive Resistance and Differential Protein Expression of Salmonella enterica Serovar Enteritidis Biofilms Exposed to Benzalkonium Chloride▿

    Science.gov (United States)

    Mangalappalli-Illathu, Anil K.; Korber, Darren R.

    2006-01-01

    The development of adaptive resistance of Salmonella enterica serovar Enteritidis ATCC 4931 biofilms following exposure to benzalkonium chloride (BC) either continuously (1 μg ml−1) or intermittently (10 μg ml−1 for 10 min daily) was examined. Biofilms adapted to BC over a 144-h period could survive a normally lethal BC challenge (500 μg ml−1 for 10 min) and then regrow, as determined by increases in biofilm thickness, total biomass, and the ratio of the viable biomass to the nonviable biomass. Exposure of untreated control biofilms to the lethal BC challenge resulted in biofilm erosion and cell death. Proteins found to be up-regulated following BC adaptation were those involved in energy metabolism (TpiA and Eno), amino acid and protein biosynthesis (WrbA, TrxA, RplL, Tsf, Tuf, DsbA, and RpoZ), nutrient binding (FruB), adaptation (CspA), detoxification (Tpx, SodB, and a probable peroxidase), and degradation of 1,2-propanediol (PduJ and PduA). A putative universal stress protein (YnaF) was also found to be up-regulated. Proteins involved in proteolysis (DegQ), cell envelope formation (RfbH), adaptation (UspA), heat shock response (DnaK), and broad regulatory functions (Hns) were found to be down-regulated following adaptation. An overall increase in cellular protein biosynthesis was deduced from the significant up-regulation of ribosomal subunit proteins, translation elongation factors, and amino acid biosynthesis protein and down-regulation of serine endoprotease. The cold shock response, stress response, and detoxification are suggested to play roles in the adaptive resistance of Salmonella serovar Enteritidis biofilms to BC. PMID:16940079

  8. Inhibition of neuraminidase inhibitor-resistant influenza virus by DAS181, a novel sialidase fusion protein.

    Directory of Open Access Journals (Sweden)

    Gallen B Triana-Baltzer

    Full Text Available Antiviral drug resistance for influenza therapies remains a concern due to the high prevalence of H1N1 2009 seasonal influenza isolates which display H274Y associated oseltamivir-resistance. Furthermore, the emergence of novel H1N1 raises the potential that additional reassortments can occur, resulting in drug resistant virus. Thus, additional antiviral approaches are urgently needed. DAS181 (Fludase, a sialidase fusion protein, has been shown to have inhibitory activity against a large number of seasonal influenza strains and a highly pathogenic avian influenza (HPAI strain (H5N1. Here, we examine the in vitro activity of DAS181 against a panel of 2009 oseltamivir-resistant seasonal H1N1 clinical isolates. The activity of DAS181 against nine 2009, two 2007, and two 2004 clinical isolates of seasonal IFV H1N1 was examined using plaque number reduction assay on MDCK cells. DAS181 strongly inhibited all tested isolates. EC50 values remained constant against isolates from 2004, 2007, and 2009, suggesting that there was no change in DAS181 sensitivity over time. As expected, all 2007 and 2009 isolates were resistant to oseltamivir, consistent with the identification of the H274Y mutation in the NA gene of all these isolates. Interestingly, several of the 2007 and 2009 isolates also exhibited reduced sensitivity to zanamivir, and accompanying HA mutations near the sialic acid binding site were observed. DAS181 inhibits IFV that is resistant to NAIs. Thus, DAS181 may offer an alternative therapeutic option for seasonal or pandemic IFVs that become resistant to currently available antiviral drugs.

  9. Systemic acquired resistance in soybean is regulated by two proteins, Orthologous to Arabidopsis NPR1

    Directory of Open Access Journals (Sweden)

    Sandhu Devinder

    2009-08-01

    Full Text Available Abstract Background Systemic acquired resistance (SAR is induced in non-inoculated leaves following infection with certain pathogenic strains. SAR is effective against many pathogens. Salicylic acid (SA is a signaling molecule of the SAR pathway. The development of SAR is associated with the induction of pathogenesis related (PR genes. Arabidopsis non-expressor of PR1 (NPR1 is a regulatory gene of the SA signal pathway 123. SAR in soybean was first reported following infection with Colletotrichum trancatum that causes anthracnose disease. We investigated if SAR in soybean is regulated by a pathway, similar to the one characterized in Arabidopsis. Results Pathogenesis-related gene GmPR1 is induced following treatment of soybean plants with the SAR inducer, 2,6-dichloroisonicotinic acid (INA or infection with the oomycete pathogen, Phytophthora sojae. In P. sojae-infected plants, SAR was induced against the bacterial pathogen, Pseudomonas syringae pv. glycinea. Soybean GmNPR1-1 and GmNPR1-2 genes showed high identities to Arabidopsis NPR1. They showed similar expression patterns among the organs, studied in this investigation. GmNPR1-1 and GmNPR1-2 are the only soybean homologues of NPR1and are located in homoeologous regions. In GmNPR1-1 and GmNPR1-2 transformed Arabidopsis npr1-1 mutant plants, SAR markers: (i PR-1 was induced following INA treatment and (ii BGL2 following infection with Pseudomonas syringae pv. tomato (Pst, and SAR was induced following Pst infection. Of the five cysteine residues, Cys82, Cys150, Cys155, Cys160, and Cys216 involved in oligomer-monomer transition in NPR1, Cys216 in GmNPR1-1 and GmNPR1-2 proteins was substituted to Ser and Leu, respectively. Conclusion Complementation analyses in Arabidopsis npr1-1 mutants revealed that homoeologous GmNPR1-1 and GmNPR1-2 genes are orthologous to Arabidopsis NPR1. Therefore, SAR pathway in soybean is most likely regulated by GmNPR1 genes. Substitution of Cys216 residue, essential

  10. Hinge Atlas: relating protein sequence to sites of structural flexibility

    Directory of Open Access Journals (Sweden)

    Yang Julie

    2007-05-01

    Full Text Available Abstract Background Relating features of protein sequences to structural hinges is important for identifying domain boundaries, understanding structure-function relationships, and designing flexibility into proteins. Efforts in this field have been hampered by the lack of a proper dataset for studying characteristics of hinges. Results Using the Molecular Motions Database we have created a Hinge Atlas of manually annotated hinges and a statistical formalism for calculating the enrichment of various types of residues in these hinges. Conclusion We found various correlations between hinges and sequence features. Some of these are expected; for instance, we found that hinges tend to occur on the surface and in coils and turns and to be enriched with small and hydrophilic residues. Others are less obvious and intuitive. In particular, we found that hinges tend to coincide with active sites, but unlike the latter they are not at all conserved in evolution. We evaluate the potential for hinge prediction based on sequence. Motions play an important role in catalysis and protein-ligand interactions. Hinge bending motions comprise the largest class of known motions. Therefore it is important to relate the hinge location to sequence features such as residue type, physicochemical class, secondary structure, solvent exposure, evolutionary conservation, and proximity to active sites. To do this, we first generated the Hinge Atlas, a set of protein motions with the hinge locations manually annotated, and then studied the coincidence of these features with the hinge location. We found that all of the features have bearing on the hinge location. Most interestingly, we found that hinges tend to occur at or near active sites and yet unlike the latter are not conserved. Less surprisingly, we found that hinge residues tend to be small, not hydrophobic or aliphatic, and occur in turns and random coils on the surface. A functional sequence based hinge predictor was

  11. Effects of Electro-acupuncture on Insulin Resistance and Hypothalamic Agouti Gene-related Protein and Neuropeptide Y in Obesity Rats%电针对单纯性肥胖大鼠胰岛素抵抗及下丘脑刺鼠基因相关蛋白、神经肽Y的影响

    Institute of Scientific and Technical Information of China (English)

    刘霞; 何军锋; 屈娅婷; 刘志君; 蒲庆阳; 郭胜童; 杜佳; 蒋鹏飞

    2016-01-01

    目的:观察电针对饮食诱导的单纯性肥胖大鼠体质量、胰岛素抵抗及下丘脑刺鼠基因相关蛋白(AGRP)、神经肽Y(NPY)基因表达的影响,探讨电针治疗肥胖症的相关机制。方法50只SD雄性大鼠随机分为低脂组10只和高脂组40只,高脂组大鼠造模成功后,随机分为模型组、电针组、西药组,每组10只。电针组电针“后三里”和“曲池”,每日1次,每次20 min,连续28 d;西药组予奥利司他灌胃,低脂组和模型组不做治疗。每日记录大鼠体质量,检测空腹血糖和胰岛素,RT-qPCR检测下丘脑AGRP和NPY基因表达水平,HE染色观察脂肪组织和肝脏形态。结果治疗后电针组和西药组体质量、胰岛素抵抗指数、AGRP、NPY、脂肪细胞直径均低于模型组(P<0.05),2组比较差异无统计学意义。电针组和西药组肝脏脂变情况均得到改善。结论电针通过改善胰岛素抵抗,抑制NPY和AGRP神经元的表达,达到控制体质量增长的目的。%Objective To observe the effects of electro-acupuncture (EA) on body weight, insulin resistance, hypothalamic agouti gene-related protein (AGRP) and neuropeptide Y (NPY) in diet induced obesity (DIO) rats; To discuss its mechanism for DIO.Methods Fifty SD male rats were randomly divided into low fat diet groups (LFD) and high fat diet group. After the DIO models were established, the successful model rats were randomly divided into model group, EA group and Orlistat (OLST) group. EA was applied to “Zusanli” (ST36) and “Quchi” (LI11) for 20 minutes. The treatment was done once a day for 28 days. OLST was treated with orlistat by gavage. LFD and model did not receive treatment. Body weight was recorded every day. FPG and FINS were detected. The expressions of AGRP and NPY were detected by RT-QPCR. Morphological changes of adipocyte and liver were examined by HE staining.Results The body weight, HOMA-IR, AGRP, NPY and

  12. Polygalacturonase inhibitor protein from fruits of anthracnose resistant and susceptible varieties of Chilli (Capsicum annuum L).

    Science.gov (United States)

    Shivashankar, S; Thimmareddy, C; Roy, Tapas K

    2010-08-01

    Chilli fruit is highly susceptible to anthracnose infection at the stage of harvest maturity, due to which the fruit yield in the leading commercial variety Byadgi is severely affected. Field studies on screening of several varieties for resistance to anthracnose have shown that a variety of chilli AR-4/99K is resistant to anthracnose infection. In many crops, resistance to fungal attack has been correlated with PGIP activity in developing fruits based on which transgenic varieties have been developed with resistance to fungi. The present study was carried out to determine whether anthracnose resistance in AR-4/99K was due to the increased levels of PGIP alone and/ or due to differences, if any, in the properties of PGIP. Hence, a comparative study of the properties of polygalacturonase inhibitor protein (PGIP) isolated from fruits of anthracnose resistant chilli var AR-4/99K and a susceptible variety Byadgi was conducted with the objective of utilizing the information in genetic transformation studies. Both the PGIPs from anthracnose resistant and susceptible varieties of chilli exhibited similarities in the elution pattern on Sephadex gel, DEAE cellulose, PAGE and SDS-PAGE. The two PGIPs were active over a wide range of pH and temperature. Both PGIPs showed differential inhibitory activity against polygalacturonase (PG) secreted by Colletotrichum gleosporoides, C. capsici, C. lindemuthianum, Fusarium moniliforme and Sclerotium rolfsii. The inhibitory activity of PGIP from both resistant and susceptible varieties was the highest (82% and 76%, respectively) against the PG from Colletotrichum capsici, a pathogen causing anthracnose rot of chilli, while the activity was lower (1.27 to 12.3%) on the other fungal PGs. Although PGIP activity decreased with fruit maturation in both the varieties, the resistant variety maintained a higher activity at 45 days after flowering (DAF) as compared to the susceptible variety which helped it to overcome the infection by

  13. Identification of Resistance Gene to PVY and Its Relation to Marketable Tuber Yield of PVY Resistant Potato Genotypes

    Directory of Open Access Journals (Sweden)

    Hassan Hassanabadi

    2016-10-01

    Full Text Available In this study, the Rysto gene, originaly found in wild potato (Solanum stoloniferum, confers extreme resistance against PVY. It was identified in 21 potato clones and varieties and they were evaluated for some agronomic traits. For this purpose five trials were conducted. In first trial 320 potato genotypes were planted on the farm and 55 symptomless clone and cultivars were selected. In second trial, 55 genotypes along with sensitive control genotype (Desireh were planted in 20 cm pots in the greenhouse at 15-20 °C with three replications. After five weeks, upper leaves were infected artificially with sap from tobacco fresh leaves checked for infection with PVYNTN and additional infections were repeated after 48 hours. Symptoms were recorded and all plants were tested by enzyme-linked immunosorbent assay (ELISA about 4 weeks after inoculation. Plants that showed visual symptoms or/and gave at least a positive ELISA result were considered as susceptible and symptomless response with negative ELISA results were considered as resistant. In third trial, 23 genotypes were planted in the greenhouse and the PVY infected young tobacco shoots were grafted to symptomless genotypes with negative ELISA results with three replications and were selected as resistance genotypes. In fourth trial, all the PVY resistant genotypes were checked by molecular marker (STM0003 for detection of Rysto gene. Finally four potato varieties (Jelly, Sante, White Lady and Savalan cultivars and 19 advanced clones were regarded as carriers of Rysto gene. In the fifth experiment genotypes were evaluated for marketable tuber yield of varieties and clones resistant to virus PVY in field conditions and 397009-8 clone was selected as high-yielding and tolerant genotype to PVY virus. Also, This clone did also have appropriate quality traits like oval-round tuber shape, uniform tubers, short stolon length, light yellow flesh color, yellow skin color, good tuber dry matter percent

  14. Localization of serum resistance-associated protein in Trypanosoma brucei rhodesiense and transgenic Trypanosoma brucei brucei.

    Science.gov (United States)

    Bart, Jean-Mathieu; Cordon-Obras, Carlos; Vidal, Isabel; Reed, Jennifer; Perez-Pastrana, Esperanza; Cuevas, Laureano; Field, Mark C; Carrington, Mark; Navarro, Miguel

    2015-10-01

    African trypanosomes infect a broad range of mammals, but humans and some higher primates are protected by serum trypanosome lytic factors that contain apolipoprotein L1 (ApoL1). In the human-infective subspecies of Trypanosoma brucei, Trypanosoma brucei rhodesiense, a gene product derived from the variant surface glycoprotein gene family member, serum resistance-associated protein (SRA protein), protects against ApoL1-mediated lysis. Protection against trypanosome lytic factor requires the direct interaction between SRA protein and ApoL1 within the endocytic apparatus of the trypanosome, but some uncertainty remains as to the precise mechanism and location of this interaction. In order to provide more insight into the mechanism of SRA-mediated resistance to trypanosome lytic factor, we assessed the localization of SRA in T. b. rhodesiense EATRO3 using a novel monoclonal antibody raised against SRA together with a set of well-characterized endosomal markers. By three-dimensional deconvolved immunofluorescence single-cell analysis, combined with double-labelling immunoelectron microscopy, we found that ≈ 50% of SRA protein localized to the lysosome, with the remaining population being distributed through the endocytic pathway, but apparently absent from the flagellar pocket membrane. These data suggest that the SRA/trypanolytic factor interaction is intracellular, with the concentration within the endosomes potentially crucial for ensuring a high efficiency.

  15. Testing Taxonomic Predictivity of Foliar and Tuber Resistance to Phytophthora infestans in Wild Relatives of Potato.

    Science.gov (United States)

    Khiutti, A; Spooner, D M; Jansky, S H; Halterman, D A

    2015-09-01

    Potato late blight, caused by the oomycete phytopathogen Phytophthora infestans, is a devastating disease found in potato-growing regions worldwide. Long-term management strategies to control late blight include the incorporation of host resistance to predominant strains. However, due to rapid genetic changes within pathogen populations, rapid and recurring identification and integration of novel host resistance traits is necessary. Wild relatives of potato offer a rich source of desirable traits, including late blight resistance, but screening methods can be time intensive. We tested the ability of taxonomy, ploidy, crossing group, breeding system, and geography to predict the presence of foliar and tuber late blight resistance in wild Solanum spp. Significant variation for resistance to both tuber and foliar late blight was found within and among species but there was no discernable predictive power based on taxonomic series, clade, ploidy, breeding system, elevation, or geographic location. We observed a moderate but significant correlation between tuber and foliar resistance within species. Although previously uncharacterized sources of both foliar and tuber resistance were identified, our study does not support an assumption that taxonomic or geographic data can be used to predict sources of late blight resistance in wild Solanum spp.

  16. Characterisation of a cell wall-anchored protein of Staphylococcus saprophyticus associated with linoleic acid resistance.

    Science.gov (United States)

    King, Nathan P; Sakinç, Türkan; Ben Zakour, Nouri L; Totsika, Makrina; Heras, Begoña; Simerska, Pavla; Shepherd, Mark; Gatermann, Sören G; Beatson, Scott A; Schembri, Mark A

    2012-01-15

    The Gram-positive bacterium Staphylococcus saprophyticus is the second most frequent causative agent of community-acquired urinary tract infections (UTI), accounting for up to 20% of cases. A common feature of staphylococci is colonisation of the human skin. This involves survival against innate immune defenses including antibacterial unsaturated free fatty acids such as linoleic acid which act by disrupting bacterial cell membranes. Indeed, S. saprophyticus UTI is usually preceded by perineal skin colonisation. In this study we identified a previously undescribed 73.5 kDa cell wall-anchored protein of S. saprophyticus, encoded on plasmid pSSAP2 of strain MS1146, which we termed S. saprophyticus surface protein F (SssF). The sssF gene is highly prevalent in S. saprophyticus clinical isolates and we demonstrate that the SssF protein is expressed at the cell surface. However, unlike all other characterised cell wall-anchored proteins of S. saprophyticus, we were unable to demonstrate a role for SssF in adhesion. SssF shares moderate sequence identity to a surface protein of Staphylococcus aureus (SasF) recently shown to be an important mediator of linoleic acid resistance. Using a heterologous complementation approach in a S. aureus sasF null genetic background, we demonstrate that SssF is associated with resistance to linoleic acid. We also show that S. saprophyticus strains lacking sssF are more sensitive to linoleic acid than those that possess it. Every staphylococcal genome sequenced to date encodes SssF and SasF homologues. Proteins in this family share similar predicted secondary structures consisting almost exclusively of α-helices in a probable coiled-coil formation. Our data indicate that SssF is a newly described and highly prevalent surface-localised protein of S. saprophyticus that contributes to resistance against the antibacterial effects of linoleic acid. SssF is a member of a protein family widely disseminated throughout the staphylococci.

  17. Characterisation of a cell wall-anchored protein of Staphylococcus saprophyticus associated with linoleic acid resistance

    Directory of Open Access Journals (Sweden)

    King Nathan P

    2012-01-01

    Full Text Available Abstract Background The Gram-positive bacterium Staphylococcus saprophyticus is the second most frequent causative agent of community-acquired urinary tract infections (UTI, accounting for up to 20% of cases. A common feature of staphylococci is colonisation of the human skin. This involves survival against innate immune defenses including antibacterial unsaturated free fatty acids such as linoleic acid which act by disrupting bacterial cell membranes. Indeed, S. saprophyticus UTI is usually preceded by perineal skin colonisation. Results In this study we identified a previously undescribed 73.5 kDa cell wall-anchored protein of S. saprophyticus, encoded on plasmid pSSAP2 of strain MS1146, which we termed S. saprophyticus surface protein F (SssF. The sssF gene is highly prevalent in S. saprophyticus clinical isolates and we demonstrate that the SssF protein is expressed at the cell surface. However, unlike all other characterised cell wall-anchored proteins of S. saprophyticus, we were unable to demonstrate a role for SssF in adhesion. SssF shares moderate sequence identity to a surface protein of Staphylococcus aureus (SasF recently shown to be an important mediator of linoleic acid resistance. Using a heterologous complementation approach in a S. aureus sasF null genetic background, we demonstrate that SssF is associated with resistance to linoleic acid. We also show that S. saprophyticus strains lacking sssF are more sensitive to linoleic acid than those that possess it. Every staphylococcal genome sequenced to date encodes SssF and SasF homologues. Proteins in this family share similar predicted secondary structures consisting almost exclusively of α-helices in a probable coiled-coil formation. Conclusions Our data indicate that SssF is a newly described and highly prevalent surface-localised protein of S. saprophyticus that contributes to resistance against the antibacterial effects of linoleic acid. SssF is a member of a protein family

  18. Extraction, separation, and purification of wheat gluten proteins and related proteins of barley, rye, and oats.

    Science.gov (United States)

    Tatham, A S; Gilbert, S M; Fido, R J; Shewry, P R

    2000-01-01

    The wheat proteins, which are active in celiac disease and other glutenrelated conditions, are defined as prolamins, in that they are soluble as individual subunits in alcohol-water mixtures, such as 50% (v/v) aqueous propan-1-ol or 60-70% (v/v) aqueous ethanol. However, in wheat grain and flour, about half of these subunits are present in polymers that are not soluble in alcohol-water mixtures unless disulfide bonds between the component subunits are reduced using an agent such as 2-mercaptoethanol (2-ME) or dithiothreitol (DTT). These alcohol-insoluble polymers are traditionally called glutenins and the related alcohol-soluble monomers are called gliadins; the two groups of proteins together form the major part of the gluten fraction. Gluten can be readily prepared from wheat by washing dough to remove the bulk of the starch, cell-wall material, and soluble components. It is a cohesive viscoelastic mass that contains, in addition to the gluten proteins, small amounts of other proteins, residual starch (about 25% dry wt), and lipid.

  19. Hypertension and insulin resistance are not directly related in obese dogs.

    Science.gov (United States)

    Rocchini, Albert P; Yang, John Q; Gokee, Amy

    2004-05-01

    In dogs fed a high-fat diet, we determined whether there was a direct relation between obesity-induced insulin resistance and obesity-induced hypertension. Thirty-six adult mongrel dogs were chronically instrumented and assigned to receive either a high-fat diet alone (n=7) or a high-fat diet combined with a low-sodium diet plus furosemide (n=6), prazosin plus atenolol (n=7), clonidine (n=10), or aspirin (n=6). Blood pressure, heart rate, and body weight were measured daily. Insulin resistance was assessed with a single-dose euglycemic hyperinsulinemic clamp (2 mU x kg(-1) x min(-1)) before and after 1, 3, and 6 weeks of the high-fat diet. The low-salt diet plus furosemide, prazosin plus atenolol, and clonidine treatments prevented the hypertension associated with feeding the dogs a high-fat diet. Only clonidine treatment totally prevented the development of insulin resistance, and high-dose aspirin, known to prevent insulin resistance by inhibition of the activity of IkappaB kinase-beta, decreased the degree of insulin resistance by almost 70%. However, aspirin had no effect on the development of hypertension. We conclude that obesity-induced hypertension and obesity-induced insulin resistance are not directly related. In addition, there is a suggestion that insulin resistance in this experimental model is mediated through the central and or peripheral alpha2-adrenoceptors, whereas hypertension is mediated through the alpha1- and or beta-adrenoceptors.

  20. Gas productivity related to cleat volumes derived from focused resistivity tools in coalbed methane (CBM) fields

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Y.H.; Peeters, M.; Cloud, T.A.; Van Kirk, C.W. [Kerr McGee Rocky Mountain Corporation, Denver, CO (United States)

    2006-06-15

    Cleats are critical for coal-bed methane (CBM) production, but operators usually lack a viable method to determine productivity except for costly well tests. Wireline logs, run over the CBM deposits of the Drunkards Wash Unit located in the Uinta Basin of Utah, were used to develop a new method to relate productivity to the cleat volume. The latter is derived from a focused resistivity log and the wellbore-fluid resistivity. Induction tools are unsuitable for this method, because they are dominated by borehole effects in high resistivity coals and low resistivity mud. Moreover, they read too deep to be significantly affected by the substitution of formation fluid by borehole fluid in the cleats on which the method is based. The method was demonstrated by relating cleat volume to CBM gas productivity in 24 wells, an exercise that clearly separated good from poor producers.

  1. Serum liver fatty acid binding protein levels correlate positively with obesity and insulin resistance in Chinese young adults.

    Directory of Open Access Journals (Sweden)

    Juan Shi

    Full Text Available BACKGROUND: Liver fatty acid-binding protein (FABP1 plays an inconclusive role in adiposity. We investigated the association of serum FABP1 levels with obesity and insulin resistance in Chinese young people under 30 years old. METHODOLOGY AND PRINCIPAL FINDINGS: Cross-sectional analysis including 200 obese and 172 normal-weight subjects matched for age and sex, anthropometric measurements were performed and serum FABP1 and biochemical characteristics were measured. Insulin resistance was determined by homeostasis model assessment of insulin resistance (HOMA-IR and by the insulin sensitivity index (S(i derived from Bergman's minimal model. FABP1 levels in obese subjects were significantly higher than those in normal-weight subjects (p<0.001 and the significance remained after adjustment for age, gender, alanine and aspartate aminotransferases (p<0.001. Serum FABP1 levels were significantly correlated with many metabolic-related parameters, with BMI and triglycerides as the independent determinants. FABP1 levels remained an independent risk factor of insulin resistance assessed by binary S(i (OR = 1.868 per SD unit, 95% CI [1.035-3.373], p = 0.038 after adjustment for age, sex, BMI, waist circumference, systolic blood pressure, serum triacylglycerol, total cholesterol, HDL- and LDL-cholesterol,. FABP1 levels were also elevated with an increasing number of components of the metabolic syndrome (p for trend <0.001. Multiple regression modeling for the MetS and its components demonstrated that hypertriglyceridemia and low HDL-cholesterol were significantly correlated to serum FABP1 levels. CONCLUSIONS AND SIGNIFICANCE: Serum FABP1 correlates positively with obesity and insulin resistance in Chinese young adults. Our data supports the fact that FABP1 might be an important mediator participating in fatty acid metabolism and energy balance.

  2. Activation of Pathogenesis-related Genes by the Rhizobacterium, Bacillus sp. JS, Which Induces Systemic Resistance in Tobacco Plants

    Directory of Open Access Journals (Sweden)

    Ji-Seong Kim

    2015-06-01

    Full Text Available Plant growth promoting rhizobacteria (PGPR are known to confer disease resistance to plants. Bacillus sp. JS demonstrated antifungal activities against five fungal pathogens in in vitro assays. To verify whether the volatiles of Bacillus sp. JS confer disease resistance, tobacco leaves pre-treated with the volatiles were damaged by the fungal pathogen, Rhizoctonia solani and oomycete Phytophthora nicotianae. Pre-treated tobacco leaves had smaller lesion than the control plant leaves. In pathogenesis-related (PR gene expression analysis, volatiles of Bacillus sp. JS caused the up-regulation of PR-2 encoding β-1,3-glucanase and acidic PR-3 encoding chitinase. Expression of acidic PR-4 encoding chitinase and acidic PR-9 encoding peroxidase increased gradually after exposure of the volatiles to Bacillus sp. JS. Basic PR-14 encoding lipid transfer protein was also increased. However, PR-1 genes, as markers of salicylic acid (SA induced resistance, were not expressed. These results suggested that the volatiles of Bacillus sp. JS confer disease resistance against fungal and oomycete pathogens through PR genes expression.

  3. Investigation of cell wall composition related to stem lodging resistance in wheat (Triticum aestivum L.) by FTIR spectroscopy.

    Science.gov (United States)

    Wang, Jian; Zhu, Jinmao; Huang, RuZhu; Yang, YuSheng

    2012-07-01

    We explored the rapid qualitative analysis of wheat cultivars with good lodging resistances by Fourier transform infrared resonance (FTIR) spectroscopy and multivariate statistical analysis. FTIR imaging showing that wheat stem cell walls were mainly composed of cellulose, pectin, protein, and lignin. Principal components analysis (PCA) was used to eliminate multicollinearity among multiple peak absorptions. PCA revealed the developmental internodes of wheat stems could be distributed from low to high along the load of the second principal component, which was consistent with the corresponding bands of cellulose in the FTIR spectra of the cell walls. Furthermore, four distinct stem populations could also be identified by spectral features related to their corresponding mechanical properties via PCA and cluster analysis. Histochemical staining of four types of wheat stems with various abilities to resist lodging revealed that cellulose contributed more than lignin to the ability to resist lodging. These results strongly suggested that the main cell wall component responsible for these differences was cellulose. Therefore, the combination of multivariate analysis and FTIR could rapidly screen wheat cultivars with good lodging resistance. Furthermore, the application of these methods to a much wider range of cultivars of unknown mechanical properties promises to be of interest.

  4. Insecticide resistance and activities of relative enzymes in different populations of the white backed planthopper

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@ White backed planthopper (WBPH), Sogatella furcifera (Horvath), is one of the most devastating insect pests on rice in Asia. Its control mainly depended on the chemical pesticides. Surveys of insecticide susceptibility revealed that organophosphorus and carbamate resistance has emerged since early 1980s in China and Japan. WBPH has the long distance migration property, and Heinrichs(1994) considered that the migration might influence the resistance level of planthoppers. So we conducted the comparative studies on insecticide susceptibility and activities of resistance relative enzymes in four WBPH populations collected from Zhejiang, Yunnan, and Hainan provinces of China in 1997.

  5. Sulfur activation-related extracellular proteins of Acidithiobacillus ferrooxidans

    Institute of Scientific and Technical Information of China (English)

    ZHANG Cheng-gui; ZHANG Rui-yong; XIA Jin-lan; ZHANG Qian; NIE Zhen-yuan

    2008-01-01

    The fractions of the extracellular proteins of Acidithiobacillus ferrooxidans grown on two different energy substrates,elemental sulfur and ferrous sulfate,were selectively prepared with hot water treatment and distinctly shown by two-dimensional gel electrophoresis.Some protein spots with apparently higher abundance in sulfur energy substrate than in ferrous sulfate energy substrate were identified by using MALDI-TOF/TOF.Based on peptide mass fingerprints and bioinformatical analysis,the extracellular proteins were classified according to their functions as conjugal transfer protein,pilin,vacJ lipoprotein,polysaccharide deacetylase family protein,Ser/Thr protein phosphatase family protein and hypothetical proteins.Several extracellular proteins were found abundant in thiol groups and with CXXC functional motif,these proteins may be directly involved in the sulfur activation by use of their thiol group (Pr-SH) to bond the elemental sulfur.

  6. Uncoupling of Obesity from Insulin Resistance Through a Targeted Mutation in aP2, the Adipocyte Fatty Acid Binding Protein

    Science.gov (United States)

    Hotamisligil, Gokhan S.; Johnson, Randall S.; Distel, Robert J.; Ellis, Ramsey; Papaioannou, Virginia E.; Spiegelman, Bruce M.

    1996-11-01

    Fatty acid binding proteins (FABPs) are small cytoplasmic proteins that are expressed in a highly tissue-specific manner and bind to fatty acids such as oleic and retinoic acid. Mice with a null mutation in aP2, the gene encoding the adipocyte FABP, were developmentally and metabolically normal. The aP2-deficient mice developed dietary obesity but, unlike control mice, they did not develop insulin resistance or diabetes. Also unlike their obese wild-type counterparts, obese aP2-/- animals failed to express in adipose tissue tumor necrosis factor-α (TNF-α), a molecule implicated in obesity-related insulin resistance. These results indicate that aP2 is central to the pathway that links obesity to insulin resistance, possibly by linking fatty acid metabolism to expression of TNF-α.

  7. Expression of parathyroid hormone-related protein in ameloblastomas.

    Science.gov (United States)

    Ohtsuru, Mitsunobu

    2005-12-01

    Parathyroid hormone-related protein (PTHrP) was first discovered as a causative protein for hypercalcemia, which is often seen in the malignant tumor. PTHrP binds to the parathyroid hormone 1 receptor (PTH1R) for signal transduction. PTHrP-PTH1R interactions were associated with bone resorption. The present study, therefore, sought to clarify the expression of PTHrP, parathyroid hormone (PTH) and PTH1R in ameloblastoma, using RT-PCR (N = 8), immunohistochemistry (N = 23) and ELISA (N = 11) techniques. PTHrP and B-actin mRNA were detected in the all samples. Expression of PTHrP was also seen in all of the 23 cases in ameloblastoma by immunohistochemistry. There was a significant difference in PTHrP concentration by ELISA between typical unicystic type and solid type including unicystic type 3 (p = 0.0427). Only one exhibited the weak expression of PTH1R mRNA. PTH1R was observed on osteoblasts in bone around the tumor but no expression was observed on ameloblastoma cells in tumor parenchyma by immunohistochemistry. PTH was not detected in ameloblastoma by RT-PCR, immunohistochemistory as well as ELISA. In addition, hypercalcemia and increase of serum PTHrP level was observed in one case of 8 ameloblastomas. It was suggested that PTHrP level may be associated with local bone infiltration and hypercalcemia in ameloblastoma.

  8. Deficient hippocampal insulin signaling and augmented Tau phosphorylation is related to obesity- and age-induced peripheral insulin resistance: a study in Zucker rats.

    Science.gov (United States)

    Špolcová, Andrea; Mikulášková, Barbora; Kršková, Katarína; Gajdošechová, Lucia; Zórad, Štefan; Olszanecki, Rafał; Suski, Maciej; Bujak-Giżycka, Beata; Železná, Blanka; Maletínská, Lenka

    2014-09-25

    Insulin signaling and Tau protein phosphorylation in the hippocampi of young and old obese Zucker fa/fa rats and their lean controls were assessed to determine whether obesity-induced peripheral insulin resistance and aging are risk factors for central insulin resistance and whether central insulin resistance is related to the pathologic phosphorylation of the Tau protein. Aging and obesity significantly attenuated the phosphorylation of the insulin cascade kinases Akt (protein kinase B, PKB) and GSK-3β (glycogen synthase kinase 3β) in the hippocampi of the fa/fa rats. Furthermore, the hyperphosphorylation of Tau Ser396 alone and both Tau Ser396 and Thr231 was significantly augmented by aging and obesity, respectively, in the hippocampi of these rats. Both age-induced and obesity-induced peripheral insulin resistance are associated with central insulin resistance that is linked to hyperTau phosphorylation. Peripheral hyperinsulinemia, rather than hyperglycemia, appears to promote central insulin resistance and the Tau pathology in fa/fa rats.

  9. The Arabidopsis Tellurite resistance C protein together with ALB3 is involved in photosystem II protein synthesis.

    Science.gov (United States)

    Schneider, Anja; Steinberger, Iris; Strissel, Henning; Kunz, Hans-Henning; Manavski, Nikolay; Meurer, Jörg; Burkhard, Gabi; Jarzombski, Sabine; Schünemann, Danja; Geimer, Stefan; Flügge, Ulf-Ingo; Leister, Dario

    2014-04-01

    Assembly of photosystem II (PSII) occurs sequentially and requires several auxiliary proteins, such as ALB3 (ALBINO3). Here, we describe the role of the Arabidopsis thaliana thylakoid membrane protein Tellurite resistance C (AtTerC) in this process. Knockout of AtTerC was previously shown to be seedling-lethal. This phenotype was rescued by expressing TerC fused C-terminally to GFP in the terc-1 background, and the resulting terc-1TerC- GFP line and an artificial miRNA-based knockdown allele (amiR-TerC) were used to analyze the TerC function. The alterations in chlorophyll fluorescence and thylakoid ultrastructure observed in amiR-TerC plants and terc-1TerC- GFP were attributed to defects in PSII. We show that this phenotype resulted from a reduction in the rate of de novo synthesis of PSII core proteins, but later steps in PSII biogenesis appeared to be less affected. Yeast two-hybrid assays showed that TerC interacts with PSII proteins. In particular, its interaction with the PSII assembly factor ALB3 has been demonstrated by co-immunoprecipitation. ALB3 is thought to assist in incorporation of CP43 into PSII via interaction with Low PSII Accumulation2 (LPA2) Low PSII Accumulation3 (LPA3). Homozygous lpa2 mutants expressing amiR-TerC displayed markedly exacerbated phenotypes, leading to seedling lethality, indicating an additive effect. We propose a model in which TerC, together with ALB3, facilitates de novo synthesis of thylakoid membrane proteins, for instance CP43, at the membrane insertion step.

  10. Antibiotic resistance in healthcare-related and nosocomial spontaneous bacterial peritonitis.

    Science.gov (United States)

    Lutz, Philipp; Nischalke, Hans Dieter; Krämer, Benjamin; Goeser, Felix; Kaczmarek, Dominik J; Schlabe, Stefan; Parcina, Marijo; Nattermann, Jacob; Hoerauf, Achim; Strassburg, Christian P; Spengler, Ulrich

    2017-01-01

    Spontaneous bacterial peritonitis (SBP) can be life threatening in patients with liver cirrhosis. In contrast to community-acquired SBP, no standard treatment has been established for healthcare-related and nosocomial SBP. We prospectively collected healthcare-related and nosocomial SBP cases from March 2012 till February 2016 at the Department of Internal Medicine I of the University of Bonn and analysed the prevalence of antibiotic resistance among the isolated bacteria. SBP was diagnosed according to international guidelines. Ciprofloxacin, ceftriaxone and meropenem were used as reference substance for resistance to quinolones, third-generation cephalosporins and carbapenems, respectively. Ninety-two SBP episodes in 86 patients were identified: 63 episodes (69%) were nosocomial. Escherichia coli, Klebsiella species, enterococci and streptococci were most frequently isolated. Frequencies of these microorganisms were comparable for healthcare-related and nosocomial SBP (14% vs. 11%, 14% vs. 8%, 14% vs. 5% and 10% vs. 6%, respectively). In general, antibiotic resistance was higher in isolates from nosocomial than from healthcare-related SBP (50% vs. 18% for quinolones, 30% vs. 11% for piperacillin-tazobactam; P > 0·05), but comparable concerning third-generation cephalosporins (30% vs. 33%). All microorganisms were sensitive to carbapenems apart from nosocomial infections with Enterococcus faecium (n = 3) and Candida albicans (n = 1) due to intrinsic resistance or lack of microbiological efficacy, respectively. No multidrug-resistant microorganisms were detected. Resistance to initial antibiotic treatment affected 30-day survival negatively (18% vs. 68%; P = 0·002). Resistance to initial antibiotic treatment was associated with increased mortality. With resistance to cephalosporins being frequent, piperacillin-tazobactam or carbapenems might be preferred as treatment of SBP. © 2016 Stichting European Society for Clinical Investigation Journal Foundation.

  11. Expression and functional activity of the ABC-transporter proteins P-glycoprotein and multidrug-resistance protein 1 in human brain tumor cells and astrocytes.

    Science.gov (United States)

    Spiegl-Kreinecker, Sabine; Buchroithner, Johanna; Elbling, Leonilla; Steiner, Elisabeth; Wurm, Gabriele; Bodenteich, Angelika; Fischer, Johannes; Micksche, Michael; Berger, Walter

    2002-03-01

    The poor prognosis of glioma patients is partly based on the minor success obtained from chemotherapeutic treatments. Resistance mechanisms at the tumor cell level may be, in addition to the blood-brain barrier, involved in the intrinsic chemo-insensitivity of brain tumors. We investigated the expression of the drug-transporter proteins P-glycoprotein (P-gp) and multidrug-resistance protein 1 (MRP1) in cell lines (N = 24) and primary cell cultures (N = 36) from neuroectodermal tumors, as well as in brain tumor extracts (N = 18) and normal human astrocytes (N = 1). We found that a considerable expression of P-gp was relatively rare in glioma cells, in contrast to MRP1, which was constitutively overexpressed in cells derived from astrocytomas as well as glioblastomas. Also, normal astrocytes cultured in vitro expressed high amounts of MRPI but no detectable P-gp. Meningioma cells frequently co-expressed P-gp and MRP1, while, most of the neuroblastoma cell lines express higher P-gp but lower MRP1 levels as compared to the other tumor types. Both, a drug-exporting and a chemoprotective function of P-gp as well as MRP1 could be demonstrated in selected tumor cells by a significant upregulation of cellular 3H-daunomycin accumulation and daunomycin cytotoxicity via administration of transporter antagonists. Summing up, our data suggest that P-gp contributes to cellular resistance merely in a small subgroup of gliomas, but frequently in neuroblastomas and meningiomas. In contrast, MRP1 is demonstrated to play a constitutive role in the intrinsic chemoresistance of gliomas and their normal cell counterpart.

  12. Structure-function analysis of the NB-ARC domain of plant disease resistance proteins.

    Science.gov (United States)

    van Ooijen, Gerben; Mayr, Gabriele; Kasiem, Mobien M A; Albrecht, Mario; Cornelissen, Ben J C; Takken, Frank L W

    2008-01-01

    Resistance (R) proteins in plants are involved in pathogen recognition and subsequent activation of innate immune responses. Most resistance proteins contain a central nucleotide-binding domain. This so-called NB-ARC domain consists of three subdomains: NB, ARC1, and ARC2. The NB-ARC domain is a functional ATPase domain, and its nucleotide-binding state is proposed to regulate activity of the R protein. A highly conserved methionine-histidine-aspartate (MHD) motif is present at the carboxy-terminus of ARC2. An extensive mutational analysis of the MHD motif in the R proteins I-2 and Mi-1 is reported. Several novel autoactivating mutations of the MHD invariant histidine and conserved aspartate were identified. The combination of MHD mutants with autoactivating hydrolysis mutants in the NB subdomain showed that the autoactivation phenotypes are not additive. This finding indicates an important regulatory role for the MHD motif in the control of R protein activity. To explain these observations, a three-dimensional model of the NB-ARC domain of I-2 was built, based on the APAF-1 template structure. The model was used to identify residues important for I-2 function. Substitution of the selected residues resulted in the expected distinct phenotypes. Based on the model, it is proposed that the MHD motif fulfils the same function as the sensor II motif found in AAA+ proteins (ATPases associated with diverse cellular activities)-co-ordination of the nucleotide and control of subdomain interactions. The presented 3D model provides a framework for the formulation of hypotheses on how mutations in the NB-ARC exert their effects.

  13. Parathyroid hormone related protein (PTHrP) in tumor progression.

    Science.gov (United States)

    Kremer, Richard; Li, Jiarong; Camirand, Anne; Karaplis, Andrew C

    2011-01-01

    Parathyroid hormone-related protein (PTHrP) is widely expressed in fetal and adult tissues and is a key regulator for cellular calcium transport and smooth muscle cell contractility, as well as a crucial control factor in cell proliferation, development and differentiation. PTHrP stimulates or inhibits apoptosis in an autocrine/paracrine and intracrine fashion, and is particularly important for hair follicle and bone development, mammary epithelial development and tooth eruption. PTHrP's dysregulated expression has traditionally been associated with oncogenic pathologies as the major causative agent of malignancy-associated hypercalcemia, but recent evidence revealed a driving role in skeletal metastasis progression. Here, we demonstrate that PTHrP is also closely involved in breast cancer initiation, growth and metastasis through mechanisms separate from its bone turnover action, and we suggest that PTHrP as a facilitator of oncogenes would be a novel target for therapeutic purposes.

  14. Myocardin-related transcription factor regulates Nox4 protein expression

    DEFF Research Database (Denmark)

    Rozycki, Matthew; Bialik, Janne Folke; Speight, Pam

    2016-01-01

    TGFβ-induced expression of the NADPH oxidase Nox4 is essential for fibroblast-myofibroblast transition. Rho has been implicated in Nox4 regulation, but the underlying mechanisms are largely unknown. Myocardin-related transcription factor (MRTF), a Rho/actin polymerization-controlled coactivator...... translocation of MRTF. Because the Nox4 promoter harbors a serum response factor/MRTF cis-element (CC(A/T)6GG box), we asked if MRTF (and thus cytoskeleton organization) could regulate Nox4 expression. We show that Nox4 protein is robustly induced in kidney tubular cells exclusively by combined application...... of contact uncoupling and TGFβ. Nox4 knockdown abrogates epithelial-myofibroblast transition-associated reactive oxygen species production. Laser capture microdissection reveals increased Nox4 expression in the tubular epithelium also during obstructive nephropathy. MRTF down-regulation/inhibition suppresses...

  15. Effects of hypergravity on the expression of multidrug resistance proteins in human melanocytic cells

    Science.gov (United States)

    Lambers, B.; Stieber, C.; Grigorieva, O.; Block, I.; Bromeis, B.; Buravkova, L.; Gerzer, R.; Ivanova, K.

    In humans the skin serves as a barrier against potentially harmful effects of the environment Human melanocytes constitute the principal cells for skin pigmentation by synthesizing the pigment melanin Melanin acts as a scavenger for free radicals that may arise during metabolic stress The melanocytes are also able to secrete a wide range of signal molecules In previous studies we found that normal human melanocytes NHMs and non-metastatic melanoma cells respond to long-time exposure to hypergravity up to 5 g for 24 h with elevated efflux of guanosine 3 5 -cyclic monophosphate cGMP in the presence of phosphodiesterase PDE inhibitors e g 3-isobutyl-1-methylxanthine Cyclic GMP is known to play a signaling role in human melanocyte physiology It controls the signaling activities of nitric oxide NO in relation to melanogenesis as well as in melanocyte-extracellular matrix interactions that may be important for some pathological processes including metastasis The present study investigated the effects of hypergravity on the expression of the multidrug resistance proteins MRP 4 and 5 as highly selective cGMP exporters in non-stimulated and NO-stimulated NHMs and melanoma cells MCs on mRNA levels using semi-quantitative RT-PCR analysis Hypergravity up to 5 g for 24 h was produced by horizontal centrifugal acceleration The NONOate DETA-NO 0 1 mM was used as a direct NO donor for cell stimulation For 5-g experiments the mRNA levels for the highly specific cGMP transporter MRP5 appeared to be

  16. Highly Sensitive Functionalized Conducting Copolypyrrole Film for DNA Sensing and Protein-resistant%Highly Sensitive Functionalized Conducting Copolypyrrole Film for DNA Sensing and Protein-resistant

    Institute of Scientific and Technical Information of China (English)

    Zhang, Zhihong; Li, Guijuan; Yan, Fufeng; Zhang, Zhonghou; Fang, Shaoming

    2012-01-01

    In order to exploit the applications ofpolypyrrole (PPy) derivatives in biosensors and bioelectronics, the different immobilization mechanisms of biomolecules onto differently functionalized conducting PPy films are investigated. Pyrrole and pyrrole derivatives with carboxyl and amino groups were copolymerized with ω-(N-pyrrolyl)-octylthiol self-assembled on Au surface by the method of the chemical polymerization to form a layer of the copolymer film, i.e., poly[pyrrole-co-(N-pyrrolyl)-caproic acid] (poly(Py-co-PyCA)) and poly[pyrrole-co-(