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Sample records for plasmid-borne cpe gene

  1. Comparative genomic hybridization analysis shows different epidemiology of chromosomal and plasmid-borne cpe-carrying Clostridium perfringens type A.

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    Päivi Lahti

    Full Text Available Clostridium perfringens, one of the most common causes of food poisonings, can carry the enterotoxin gene, cpe, in its chromosome or on a plasmid. C. perfringens food poisonings are more frequently caused by the chromosomal cpe-carrying strains, while the plasmid-borne cpe-positive genotypes are more commonly found in the human feces and environmental samples. Different tolerance to food processing conditions by the plasmid-borne and chromosomal cpe-carrying strains has been reported, but the reservoirs and contamination routes of enterotoxin-producing C. perfringens remain unknown. A comparative genomic hybridization (CGH analysis with a DNA microarray based on three C. perfringens type A genomes was conducted to shed light on the epidemiology of C. perfringens food poisonings caused by plasmid-borne and chromosomal cpe-carrying strains by comparing chromosomal and plasmid-borne cpe-positive and cpe-negative C. perfringens isolates from human, animal, environmental, and food samples. The chromosomal and plasmid-borne cpe-positive C. perfringens genotypes formed two distinct clusters. Variable genes were involved with myo-inositol, ethanolamine and cellobiose metabolism, suggesting a new epidemiological model for C. perfringens food poisonings. The CGH results were complemented with growth studies, which demonstrated different myo-inositol, ethanolamine, and cellobiose metabolism between the chromosomal and plasmid-borne cpe-carrying strains. These findings support a ubiquitous occurrence of the plasmid-borne cpe-positive strains and their adaptation to the mammalian intestine, whereas the chromosomal cpe-positive strains appear to have a narrow niche in environments containing degrading plant material. Thus the epidemiology of the food poisonings caused by two populations appears different, the plasmid-borne cpe-positive strains probably contaminating foods via humans and the chromosomal strains being connected to plant material.

  2. Studies on the expression of plasmid-borne genes in the endosymbiotic state of Rhizobium leguminosarum

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    Krol, A.J.M.

    1982-01-01

    The subject matter of the research reported in this thesis is the role of plasmid-borne genes of Rhizobium in symbiosis and nitrogen fixation. Plasmid DNA was isolated from Rhizobium leguminosarum strain PRE and the expression of plasmid DNA in nitrogen fixing nodules was investigated by hybridizati

  3. Survival of Clostridium perfringens During Simulated Transport and Stability of Some Plasmid-borne Toxin Genes under Aerobic Conditions

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    Johansson K-E

    2005-12-01

    Full Text Available Clostridium perfringens is a pathogen of great concern in veterinary medicine, because it causes enteric diseases and different types of toxaemias in domesticated animals. It is important that bacteria in tissue samples, which have been collected in the field, survive and for the classification of C. perfringens into the correct toxin group, it is crucial that plasmid-borne genes are not lost during transportation or in the diagnostic laboratory. The objectives of this study were to investigate the survival of C. perfringens in a simulated transport of field samples and to determine the stability of the plasmid-borne toxin genes cpb1 and etx after storage at room temperature and at 4°C. Stability of the plasmid-borne genes cpb1 and etx of C. perfringens CCUG 2035, and cpb2 from C. perfringens CIP 106526, JF 2255 and 6 field isolates in aerobic atmosphere was also studied. Survival of C. perfringens was similar in all experiments. The cpb1 and etx genes were detected in all isolates from samples stored either at room temperature or at 4°C for 24–44 h. Repeated aerobic treatment of C. perfringens CCUG 2035 and CIP 106526 did not result in the loss of the plasmid-borne genes cpb1, cpb2 or etx. Plasmid-borne genes in C. perfringens were found to be more stable than generally reported. Therefore, C. perfringens toxinotyping by PCR can be performed reliably, as the risk of plasmid loss seems to be a minor problem.

  4. Organization of the cpe locus in CPE-positive clostridium perfringens type C and D isolates.

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    Jihong Li

    Full Text Available Clostridium perfringens enterotoxin (encoded by the cpe gene contributes to several important human, and possibly veterinary, enteric diseases. The current study investigated whether cpe locus organization in type C or D isolates resembles one of the three (one chromosomal and two plasmid-borne cpe loci commonly found amongst type A isolates. Multiplex PCR assays capable of detecting sequences in those type A cpe loci failed to amplify products from cpe-positive type C and D isolates, indicating these isolates possess different cpe locus arrangements. Therefore, restriction fragments containing the cpe gene were cloned and sequenced from two type C isolates and one type D isolate. The obtained cpe locus sequences were then used to construct an overlapping PCR assay to assess cpe locus diversity amongst other cpe-positive type C and D isolates. All seven surveyed cpe-positive type C isolates had a plasmid-borne cpe locus partially resembling the cpe locus of type A isolates carrying a chromosomal cpe gene. In contrast, all eight type D isolates shared the same plasmid-borne cpe locus, which differed substantially from the cpe locus present in other C. perfringens by containing two copies of an ORF with 67% identity to a transposase gene (COG4644 found in Tn1546, but not previously associated with the cpe gene. These results identify greater diversity amongst cpe locus organization than previously appreciated, providing new insights into cpe locus evolution. Finally, evidence for cpe gene mobilization was found for both type C and D isolates, which could explain their cpe plasmid diversity.

  5. Organization of the cpe Locus in CPE-Positive Clostridium perfringens Type C and D Isolates

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    Li, Jihong; Miyamoto, Kazuaki; Sayeed, Sameera; McClane, Bruce A.

    2010-01-01

    Clostridium perfringens enterotoxin (encoded by the cpe gene) contributes to several important human, and possibly veterinary, enteric diseases. The current study investigated whether cpe locus organization in type C or D isolates resembles one of the three (one chromosomal and two plasmid-borne) cpe loci commonly found amongst type A isolates. Multiplex PCR assays capable of detecting sequences in those type A cpe loci failed to amplify products from cpe-positive type C and D isolates, indicating these isolates possess different cpe locus arrangements. Therefore, restriction fragments containing the cpe gene were cloned and sequenced from two type C isolates and one type D isolate. The obtained cpe locus sequences were then used to construct an overlapping PCR assay to assess cpe locus diversity amongst other cpe-positive type C and D isolates. All seven surveyed cpe-positive type C isolates had a plasmid-borne cpe locus partially resembling the cpe locus of type A isolates carrying a chromosomal cpe gene. In contrast, all eight type D isolates shared the same plasmid-borne cpe locus, which differed substantially from the cpe locus present in other C. perfringens by containing two copies of an ORF with 67% identity to a transposase gene (COG4644) found in Tn1546, but not previously associated with the cpe gene. These results identify greater diversity amongst cpe locus organization than previously appreciated, providing new insights into cpe locus evolution. Finally, evidence for cpe gene mobilization was found for both type C and D isolates, which could explain their cpe plasmid diversity. PMID:20532170

  6. Evidence that plasmid-borne botulinum neurotoxin type B genes are widespread among Clostridium botulinum serotype B strains.

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    Giovanna Franciosa

    Full Text Available BACKGROUND: Plasmids that encode certain subtypes of the botulinum neurotoxin type B have recently been detected in some Clostridium botulinum strains. The objective of the present study was to investigate the frequency with which plasmid carriage of the botulinum neurotoxin type B gene (bont/B occurs in strains of C. botulinum type B, Ab, and A(B, and whether plasmid carriage is bont/B subtype-related. METHODOLOGY/PRINCIPAL FINDINGS: PCR-Restriction fragment length polymorphism was employed to identify subtypes of the bont/B gene. Pulsed-field gel electrophoresis and Southern blot hybridization with specific probes were performed to analyze the genomic location of the bont/B subtype genes. All five known bont/B subtype genes were detected among the strains; the most frequently detected subtype genes were bont/B1 and /B2. Surprisingly, the bont/B subtype gene was shown to be plasmid-borne in >50% of the total strains. The same bont/B subtype gene was associated with the chromosome in some strains, whereas it was associated with a plasmid in others. All five known bont/B subtype genes were in some cases found to reside on plasmids, though with varying frequency (e.g., most of the bont/B1 subtype genes were located on plasmids, whereas all but one of the bont/B2 subtypes were chromosomally-located. Three bivalent isolates carried both bont/A and /B genes on the same plasmid. The plasmids carrying the bont gene were five different sizes, ranging from approximately 55 kb to approximately 245 kb. CONCLUSIONS/SIGNIFICANCE: The unexpected finding of the widespread distribution of plasmids harboring the bont/B gene among C. botulinum serotype B strains provides a chance to examine their contribution to the dissemination of the bont genes among heterogeneous clostridia, with potential implications on issues related to pathogenesis and food safety.

  7. Bacillus stearothermophilus contains a plasmid-borne gene for alpha-amylase.

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    Mielenz, J R

    1983-01-01

    The gene for thermostable alpha-amylase from the thermophilic bacterium Bacillus stearothermophilus has been cloned and expressed in Escherichia coli. Each alpha-amylase-producing colony contained at least a 9.7-kilobase-pair (kb) chimeric plasmid composed of the vector pBR322 and a common 5.4-kb HindIII fragment of DNA. B. stearothermophilus contains four plasmids with sizes from 12 kb to over 108 kb. Restriction endonuclease analysis of these naturally occurring plasmids showed they also contain a 5.4-kb HindIII fragment of DNA. Cloning experiments with the four plasmids yielded alpha-amylase-producing E. coli that contained the same 9.7-kb chimeric plasmid. Restriction endonuclease analysis and further recombinant DNA experiments identified a 26-kb plasmid that contains the gene for alpha-amylase. A spontaneous mutant of B. stearothermophilus unable to produce alpha-amylase was missing the 26-kb plasmid but contained a 20-kb plasmid. A 6-kb deletion within the region of the 5.4-kb HindIII fragment yielded the 20-kb plasmid unable to code for alpha-amylase. A nick-translated probe for the alpha-amylase coding region did not hybridize to either plasmid or total cellular DNA from this mutant strain of B. stearothermophilus. These results demonstrate the gene for alpha-amylase is located exclusively on a 26-kb plasmid in B. stearothermophilus with no genetic counterpart present on the chromosome. Images PMID:6193526

  8. Plasmid-borne prokaryotic gene expression: Sources of variability and quantitative system characterization

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    Bagh, Sangram; Mazumder, Mostafizur; Velauthapillai, Tharsan; Sardana, Vandit; Dong, Guang Qiang; Movva, Ashok B.; Lim, Len H.; McMillen, David R.

    2008-02-01

    One aim of synthetic biology is to exert systematic control over cellular behavior, either for medical purposes or to “program” microorganisms. An engineering approach to the design of biological controllers demands a quantitative understanding of the dynamics of both the system to be controlled and the controllers themselves. Here we focus on a widely used method of exerting control in bacterial cells: plasmid vectors bearing gene-promoter pairs. We study two variants of the simplest such element, an unregulated promoter constitutively expressing its gene, against the varying genomic background of four Escherichia coli cell strains. Absolute protein numbers and rates of expression vary with both cell strain and plasmid type, as does the variability of expression across the population. Total variability is most strongly coupled to the cell division process, and after cell size is scaled away, plasmid copy number regulation emerges as a significant effect. We present simple models that capture the main features of the system behavior. Our results confirm that complex interactions between plasmids and their hosts can have significant effects on both expression and variability, even in deliberately simplified systems.

  9. Characterization of a Novel Plasmid-Borne Thiopeptide Gene Cluster in Staphylococcus epidermidis Strain 115

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    Bennallack, Philip R.; Burt, Scott R.; Heder, Michael J.

    2014-01-01

    Thiopeptides are small (12- to 17-amino-acid), heavily modified peptides of bacterial origin. This antibiotic family, with more than 100 known members, is characterized by the presence of sulfur-containing heterocyclic rings and dehydrated residues within a macrocyclic peptide structure. Thiopeptides, including micrococcin P1, have garnered significant attention in recent years for their potent antimicrobial activity against bacteria, fungi, and even protozoa. Micrococcin P1 is known to target the ribosome; however, like those of other thiopeptides, its biosynthesis and mechanisms of self-immunity are poorly characterized. We have discovered an isolate of Staphylococcus epidermidis harboring the genes for thiopeptide production and self-protection on a 24-kb plasmid. Here we report the characterization of this plasmid, identify the antimicrobial peptide that it encodes, and provide evidence of a target replacement-mediated mechanism of self-immunity. PMID:25313391

  10. Inducible colistin resistance via a disrupted plasmid-borne mcr-1 gene in a 2008 Vietnamese Shigella sonnei isolate

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    Pham Thanh, Duy; Thanh Tuyen, Ha; Nguyen Thi Nguyen, To; Chung The, Hao; Wick, Ryan R.; Thwaites, Guy E.; Baker, Stephen; Holt, Kathryn E.

    2016-01-01

    Objectives The objective of this study was to assess the presence of mcr-1 in Shigella sonnei isolated in Vietnam. Methods WGS data were analysed for the presence of the mcr-1 gene sequence. The association of mcr-1 with a plasmid was assessed by PCR and by conjugation. Results Through genome sequencing we identified a plasmid-associated inactive form of mcr-1 in a 2008 Vietnamese isolate of Shigella sonnei. The plasmid was conjugated into Escherichia coli and mcr-1 was activated upon exposure to colistin, resulting in highly colistin-resistant transconjugants. Conclusions This is the first description of the mcr-1 gene in Shigella, which is atypical given that colistin is not ordinarily used to treat diarrhoea. Our data suggest the mcr-1 gene has been circulating in human-restricted pathogens for some time but likely carries a selective fitness cost. PMID:27246235

  11. Occurrence of Plasmid Borne Multiple Antibiotic Resistant Genes in Escherichia coli Isolated from Well Water in Eku, Ethiope East Local Government Area, Delta State, Nigeria

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    E. Akponah

    2014-05-01

    Full Text Available Five wells in Eku were assessed for total heterotrophic bacterial and coliform counts from January to December. Sixty isolates of Escherichia coli were also obtained from the well water samples throughout the study period. It was observed that, values of total heterotrophic bacterial and coliform load obtained varied with seasons although the total heterotrophic bacterial counts were significantly higher than the coliform load at all times. During the dry season, values of the total heterotrophic bacterial count ranged from 2.08 to 5.48 (log cfu/mL while coliform counts ranged from 2.3 to 3.26 (log cfu/mL. On the other hand, total heterotrophic bacterial and coliform counts ranged from 3.34 to 7.14 (log cfu/mL and 3.15 to 3.98 (log cfu/mL respectively during the rainy season. Results obtained revealed that 76.6% of total Escherichia coli isolates evaluated, demonstrated multiple antibiotics resistance while 18.3% showed single antibiotics resistance. On curing, 83.3% of test Escherichia coli population lost their antibiotics resistant gene indicating that these genes resided on plasmid.

  12. Conjugative transfer of an IncA/C plasmid-borne blaCMY-2 gene through genetic re-arrangements with an IncX1 plasmid.

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    Wiesner, Magdalena; Fernández-Mora, Marcos; Cevallos, Miguel A; Zavala-Alvarado, Crispín; Zaidi, Mussaret B; Calva, Edmundo; Silva, Claudia

    2013-11-21

    Our observation that in the Mexican Salmonella Typhimurium population none of the ST19 and ST213 strains harbored both the Salmonella virulence plasmid (pSTV) and the prevalent IncA/C plasmid (pA/C) led us to hypothesize that restriction to horizontal transfer of these plasmids existed. We designed a conjugation scheme using ST213 strain YU39 as donor of the blaCMY-2 gene (conferring resistance to ceftriaxone; CRO) carried by pA/C, and two E. coli lab strains (DH5α and HB101) and two Typhimurium ST19 strains (SO1 and LT2) carrying pSTV as recipients. The aim of this study was to determine if the genetic background of the different recipient strains affected the transfer frequencies of pA/C. YU39 was able to transfer CRO resistance, via a novel conjugative mechanism, to all the recipient strains although at low frequencies (10-7 to 10-10). The presence of pSTV in the recipients had little effect on the conjugation frequency. The analysis of the transconjugants showed that three different phenomena were occurring associated to the transfer of blaCMY-2: 1) the co-integration of pA/C and pX1; 2) the transposition of the CMY region from pA/C to pX1; or 3) the rearrangement of pA/C. In addition, the co-lateral mobilization of a small (5 kb) ColE1-like plasmid was observed. The transconjugant plasmids involving pX1 re-arrangements (either via co-integration or ISEcp1-mediated transposition) obtained the capacity to conjugate at very high levels, similar to those found for pX1 (10-1). Two versions of the region containing blaCMY-2 were found to transpose to pX1: the large version was inserted into an intergenic region located where the "genetic load" operons are frequently inserted into pX1, while the short version was inserted into the stbDE operon involved in plasmid addiction system. This is the first study to report the acquisition of an extended spectrum cephalosporin (ESC)-resistance gene by an IncX1 plasmid. We showed that the transfer of the YU39 blaCMY-2 gene

  13. Trans activation of plasmid-borne promoters by adenovirus and several herpes group viruses.

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    Everett, R D; Dunlop, M

    1984-01-01

    This paper describes experiments to test the ability of a number of viruses of the Herpes group, and also Adenovirus-2 and SV40, to activate transcription from the Herpes simplex virus-1 glycoprotein D and the rabbit beta-globin promoters. Plasmids containing these genes were transfected into HeLa cells which were then infected with various viruses. Transcriptional activation in trans of the plasmid-borne promoters was monitored by quantitative S1 nuclease analysis of total cytoplasmic RNA is...

  14. In vitro cytotoxicity induced by Clostridium perfringens isolate carrying a chromosomal cpe gene is exclusively dependent on sporulation and enterotoxin production.

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    Yasugi, Mayo; Sugahara, Yuki; Hoshi, Hidenobu; Kondo, Kaori; Talukdar, Prabhat K; Sarker, Mahfuzur R; Yamamoto, Shigeki; Kamata, Yoichi; Miyake, Masami

    2015-08-01

    Clostridium perfringens type A is a common source of food poisoning (FP) and non-food-borne (NFB) gastrointestinal diseases in humans. In the intestinal tract, the vegetative cells sporulate and produce a major pathogenic factor, C. perfringens enterotoxin (CPE). Most type A FP isolates carry a chromosomal cpe gene, whereas NFB type A isolates typically carry a plasmid-encoded cpe. In vitro, the purified CPE protein binds to a receptor and forms pores, exerting a cytotoxic activity in epithelial cells. However, it remains unclear if CPE is indispensable for C. perfringens cytotoxicity. In this study, we examined the cytotoxicity of cpe-harboring C. perfringens isolates co-cultured with human intestinal epithelial Caco-2 cells. The FP strains showed severe cytotoxicity during sporulation and CPE production, but not during vegetative cell growth. While Caco-2 cells were intact during co-culturing with cpe-null mutant derivative of strain SM101 (a FP strain carrying a chromosomal cpe gene), the wild-type level cytotoxicity was observed with cpe-complemented strain. In contrast, both wild-type and cpe-null mutant derivative of the NFB strain F4969 induced Caco-2 cell death during both vegetative and sporulation growth. Collectively, the Caco-2 cell cytotoxicity caused by C. perfringens strain SM101 is considered to be exclusively dependent on CPE production, whereas some additional toxins should be involved in F4969-mediated in vitro cytotoxicity.

  15. Localization and physical mapping of a plasmid-borne 23-kb nif gene cluster from Enterobacter agglomerans showing homology to the entire nif gene cluster of Klebsiella pneumoniae M5a1.

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    Singh, M; Kreutzer, R; Acker, G; Klingmüller, W

    1988-01-01

    A physical and genetical map of the plasmid pEA3 indigenous to Enterobacter agglomerans is presented. pEA3 is a 111-kb large plasmid containing a 23-kb large cluster of nif genes which shows extensive homology (Southern hybridization and heteroduplex analysis) to the entire nif gene cluster of Klebsiella pneumoniae (Kp) M5a1. All the nif genes on pEA3 are organized in the same manner as in K. pneumoniae, except nifJ, which is located on the left end of pEA3 nif gene cluster (near nifQB). A BamHI restriction map of pEA3 and a detailed restriction map of the 23-kb nif region on pEA3 is also presented. The nif genes of pEA3 showed a low level of acetylene reduction in Escherichia coli, demonstrating that these genes are functional and contain the whole genetic information required to fix nitrogen. The origin of vegetative replication (OriV) of pEA3 was localized about 5.5 kb from the right end of the nif gene cluster. In addition to pEA3, large plasmids from four other strains of E. agglomerans showed homology to all the Kp nif genes tested, indicating that in diazotrophic strains of E. agglomerans nif genes are usually located on plasmids. In contrast, in most of the free-living, nitrogen-fixing bacteria the nif genes are on chromosome.

  16. The pleiotropic vegetative and sexual development phenotypes of Neurospora crassa arise from double mutants of the calcium signaling genes plc-1, splA2, and cpe-1.

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    Barman, Ananya; Tamuli, Ranjan

    2017-03-06

    We investigated phenotypes of the double mutants of the calcium (Ca(2+)) signaling genes plc-1, splA2, and cpe-1 encoding for a phospholipase C1 (PLC-1), a secretory phospholipase A2 (sPLA2), and a Ca(2+)/H(+) exchanger (CPE-1), respectively, to understand the cell functions regulated by their genetic interactions. Mutants lacking plc-1 and either splA2 or cpe-1 exhibited numerous defects including reduced colonial growth, stunted aerial hyphae, premature conidiation on plates with delayed germination, inappropriate conidiation in submerged culture, and lesser mycelial pigmentation. Moreover, the ∆plc-1; ∆splA2 and ∆plc-1; ∆cpe-1 double mutants were female-sterile when crossed with wild type as the male parent. In addition, ∆plc-1, ∆splA2, and ∆cpe-1 single mutants displayed higher carotenoid accumulation and an increased level of intracellular reactive oxygen species (ROS). Therefore, the pleiotropic phenotype of the double mutants of plc-1, splA2, and cpe-1 suggested that the genetic interaction of these genes plays a critical role for normal vegetative and sexual development in N. crassa.

  17. Prevalence and characterization of enterotoxin gene-carrying Clostridium perfringens isolates from retail meat products in Japan.

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    Miki, Yasuhiro; Miyamoto, Kazuaki; Kaneko-Hirano, Ikuko; Fujiuchi, Kanako; Akimoto, Shigeru

    2008-09-01

    Clostridium perfringens is an important anaerobic pathogen causing food-borne gastrointestinal (GI) diseases in humans and animals. It is thought that C. perfringens food poisoning isolates typically carry the enterotoxin gene (cpe) on their chromosome, while isolates from other GI diseases, such as antibiotic-associated diarrhea, carry cpe on a transferable plasmid. However, food-borne GI disease outbreaks associated with C. perfringens isolates carrying plasmid-borne cpe (plasmid cpe isolates) were recently reported in Japan and Europe. To investigate whether retail food can be a reservoir for food poisoning generally, we evaluated Japanese retail meat products for the presence of two genotypes of enterotoxigenic C. perfringens. Our results demonstrated that approximately 70% of the Japanese retail raw meat samples tested were contaminated with low numbers of C. perfringens bacteria and 4% were contaminated with cpe-positive C. perfringens. Most of the cpe-positive C. perfringens isolates obtained from Japanese retail meat carried cpe on a plasmid. The plasmid cpe isolates exhibited lower spore heat resistance than did chromosomal cpe isolates. Collectively, these plasmid cpe isolates might be causative agents of food poisoning when foods are contaminated with these isolates from equipment and/or the environment after cooking, or they may survive in food that has not been cooked at a high enough temperature.

  18. Prevalence and Characterization of Enterotoxin Gene-Carrying Clostridium perfringens Isolates from Retail Meat Products in Japan▿

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    Miki, Yasuhiro; Miyamoto, Kazuaki; Kaneko-Hirano, Ikuko; Fujiuchi, Kanako; Akimoto, Shigeru

    2008-01-01

    Clostridium perfringens is an important anaerobic pathogen causing food-borne gastrointestinal (GI) diseases in humans and animals. It is thought that C. perfringens food poisoning isolates typically carry the enterotoxin gene (cpe) on their chromosome, while isolates from other GI diseases, such as antibiotic-associated diarrhea, carry cpe on a transferable plasmid. However, food-borne GI disease outbreaks associated with C. perfringens isolates carrying plasmid-borne cpe (plasmid cpe isolates) were recently reported in Japan and Europe. To investigate whether retail food can be a reservoir for food poisoning generally, we evaluated Japanese retail meat products for the presence of two genotypes of enterotoxigenic C. perfringens. Our results demonstrated that approximately 70% of the Japanese retail raw meat samples tested were contaminated with low numbers of C. perfringens bacteria and 4% were contaminated with cpe-positive C. perfringens. Most of the cpe-positive C. perfringens isolates obtained from Japanese retail meat carried cpe on a plasmid. The plasmid cpe isolates exhibited lower spore heat resistance than did chromosomal cpe isolates. Collectively, these plasmid cpe isolates might be causative agents of food poisoning when foods are contaminated with these isolates from equipment and/or the environment after cooking, or they may survive in food that has not been cooked at a high enough temperature. PMID:18606797

  19. A Transmissible Plasmid-Borne Pathogenicity Island Confers Piscibactin Biosynthesis in the Fish Pathogen Photobacterium damselae subsp. piscicida

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    Rivas, Amable J.; Balado, Miguel; Fuentes-Monteverde, Juan Carlos; Rodríguez, Jaime; Jiménez, Carlos; Lemos, Manuel L.; Waldor, Matthew K.

    2015-01-01

    The fish pathogen Photobacterium damselae subsp. piscicida produces the siderophore piscibactin. A gene cluster that resembles the Yersinia high-pathogenicity island (HPI) encodes piscibactin biosynthesis. Here, we report that this HPI-like cluster is part of a hitherto-uncharacterized 68-kb plasmid dubbed pPHDP70. This plasmid lacks homologs of genes that mediate conjugation, but we found that it could be transferred at low frequencies from P. damselae subsp. piscicida to a mollusk pathogenic Vibrio alginolyticus strain and to other Gram-negative bacteria, likely dependent on the conjugative functions of the coresident plasmid pPHDP60. Following its conjugative transfer, pPHDP70 restored the capacity of a vibrioferrin mutant of V. alginolyticus to grow under low-iron conditions, and piscibactin became detectable in its supernatant. Thus, pPHDP70 appears to harbor all the genes required for piscibactin biosynthesis and transport. P. damselae subsp. piscicida strains cured of pPHDP70 no longer produced piscibactin, had impaired growth under iron-limited conditions, and exhibited markedly decreased virulence in fish. Collectively, our findings highlight the importance of pPHDP70, with its capacity for piscibactin-mediated iron acquisition, in the virulence of P. damselae subsp. piscicida. Horizontal transmission of this plasmid-borne piscibactin synthesis gene cluster in the marine environment may facilitate the emergence of new pathogens. PMID:26092457

  20. Performance of the BD MAX™ instrument with Check-Direct CPE real-time PCR for the detection of carbapenemase genes from rectal swabs, in a setting with endemic dissemination of carbapenemase-producing Enterobacteriaceae.

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    Antonelli, Alberto; Arena, Fabio; Giani, Tommaso; Colavecchio, Olga Lorenza; Valeva, Stoyanka Valentinova; Paule, Suzanne; Boleij, Peter; Rossolini, Gian Maria

    2016-09-01

    Carbapenemase-producing Enterobacteriaceae (CPE) represent an increasing public health issue and the early detection of colonization by CPE can help the implementation of infection control measures among inpatients. In this study, BD MAX Check-Direct CPE screen, with two different Master Mixes (BDMix and CPMix), using the automatic BD MAX(™) instrument, was evaluated for the detection of blaKPC, blaOXA-48, blaVIM and blaNDM genes, in comparison to selective broth enrichment and direct culture from rectal swabs. Among a total of 557 rectal swabs samples, 29 (5.2%) tested positive for CPE (23 for blaKPC, 5 for blaVIM and one for blaOXA-48). The sensitivity, specificity, positive and negative likelihood ratios values were 93.1%, 97.3%, 34.5 and 0.07, for BMix, and 100%, 97.1 %, 34.5 and 0 for CPMix, respectively. Five samples were positive with molecular methods only. The turn-around time was reduced from 18-24 hours (direct culture), or 48 h (broth enrichment) to only 3 h.

  1. Enumeration and isolation of cpe-positive Clostridium perfringens spores from feces.

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    Heikinheimo, Annamari; Lindström, Miia; Korkeala, Hannu

    2004-09-01

    A hydrophobic grid membrane filter-colony hybridization (HGMF-CH) method for the enumeration and isolation of cpe gene-carrying (cpe-positive) Clostridium perfringens spores from feces was developed. A 425-bp DNA probe specific for the cpe gene was sensitive and specific when tested with bacterial DNA and pure cultures. The enumeration of cpe-positive C. perfringens by the HGMF-CH method proved to be as sensitive as nested PCR combined with the most-probable number technique when tested with fecal samples from healthy individuals. With the aid of the HGMF-CH method, positive hybridization signals were detected from two out of seven fecal samples obtained from healthy individuals. Furthermore, cpe-positive C. perfringens was successfully isolated from both of these samples. The detection of cpe-positive C. perfringens by the HGMF-CH method is dependent on the ratio of cpe-positive C. perfringens colonies to total C. perfringens colonies growing on the HGMF-tryptose-sulfite-cycloserine plate. cpe-positive C. perfringens could be isolated if the ratio of cpe-positive C. perfringens spores to total C. perfringens spores was 6 x 10(-5) or higher. The HGMF-CH method provides an aid in the investigation of fecal samples of patients suffering from food poisoning or other diseases caused by cpe-positive C. perfringens. The method also offers a new approach in the investigation of the epidemiology of cpe-positive C. perfringens strains.

  2. Characterization of a Novel Plasmid-Borne Thiopeptide Gene Cluster in Staphylococcus epidermidis Strain 115

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    Bennallack, Philip R.; Burt, Scott R.; Heder, Michael J.; Richard A. Robison; Griffitts, Joel S.

    2014-01-01

    Thiopeptides are small (12- to 17-amino-acid), heavily modified peptides of bacterial origin. This antibiotic family, with more than 100 known members, is characterized by the presence of sulfur-containing heterocyclic rings and dehydrated residues within a macrocyclic peptide structure. Thiopeptides, including micrococcin P1, have garnered significant attention in recent years for their potent antimicrobial activity against bacteria, fungi, and even protozoa. Micrococcin P1 is known to targe...

  3. Enumeration and Isolation of cpe-Positive Clostridium perfringens Spores from Feces

    OpenAIRE

    Heikinheimo, A.; Lindström, M.; Korkeala, H

    2004-01-01

    A hydrophobic grid membrane filter-colony hybridization (HGMF-CH) method for the enumeration and isolation of cpe gene-carrying (cpe-positive) Clostridium perfringens spores from feces was developed. A 425-bp DNA probe specific for the cpe gene was sensitive and specific when tested with bacterial DNA and pure cultures. The enumeration of cpe-positive C. perfringens by the HGMF-CH method proved to be as sensitive as nested PCR combined with the most-probable number technique when tested with ...

  4. Noncytotoxic Clostridium perfringens enterotoxin (CPE) variants localize CPE intestinal binding and demonstrate a relationship between CPE-induced cytotoxicity and enterotoxicity.

    Science.gov (United States)

    Smedley, James G; Saputo, Juliann; Parker, Jacquelyn C; Fernandez-Miyakawa, Mariano E; Robertson, Susan L; McClane, Bruce A; Uzal, Francisco A

    2008-08-01

    Clostridium perfringens enterotoxin (CPE) causes the symptoms of a very common food poisoning. To assess whether CPE-induced cytotoxicity is necessary for enterotoxicity, a rabbit ileal loop model was used to compare the in vivo effects of native CPE or recombinant CPE (rCPE), both of which are cytotoxic, with those of the noncytotoxic rCPE variants rCPE D48A and rCPE(168-319). Both CPE and rCPE elicited significant fluid accumulation in rabbit ileal loops, along with severe mucosal damage that starts at villus tips and then progressively affects the entire villus, including necrosis of epithelium and lamina propria, villus blunting and fusion, and transmural edema and hemorrhage. Similar treatment of ileal loops with either of the noncytotoxic rCPE variants produced no visible histologic damage or fluid transport changes. Immunohistochemistry revealed strong CPE or rCPE(168-319) binding to villus tips, which correlated with the abundant presence of claudin-4, a known CPE receptor, in this villus region. These results support (i) cytotoxicity being necessary for CPE-induced enterotoxicity, (ii) the CPE sensitivity of villus tips being at least partially attributable to the abundant presence of receptors in this villus region, and (iii) claudin-4 being an important intestinal receptor for CPE. Finally, rCPE(168-319) was able to partially inhibit CPE-induced histologic damage, suggesting that noncytotoxic rCPE variants might be useful for protecting against some intestinal effects of CPE.

  5. Whole genome sequencing and analysis of Campylobacter coli YH502 from retail chicken reveals a plasmid-borne type VI secretion system

    Directory of Open Access Journals (Sweden)

    Sandeep Ghatak

    2017-03-01

    Full Text Available Campylobacter is a major cause of foodborne illnesses worldwide. Campylobacter infections, commonly caused by ingestion of undercooked poultry and meat products, can lead to gastroenteritis and chronic reactive arthritis in humans. Whole genome sequencing (WGS is a powerful technology that provides comprehensive genetic information about bacteria and is increasingly being applied to study foodborne pathogens: e.g., evolution, epidemiology/outbreak investigation, and detection. Herein we report the complete genome sequence of Campylobacter coli strain YH502 isolated from retail chicken in the United States. WGS, de novo assembly, and annotation of the genome revealed a chromosome of 1,718,974 bp and a mega-plasmid (pCOS502 of 125,964 bp. GC content of the genome was 31.2% with 1931 coding sequences and 53 non-coding RNAs. Multiple virulence factors including a plasmid-borne type VI secretion system and antimicrobial resistance genes (beta-lactams, fluoroquinolones, and aminoglycoside were found. The presence of T6SS in a mobile genetic element (plasmid suggests plausible horizontal transfer of these virulence genes to other organisms. The C. coli YH502 genome also harbors CRISPR sequences and associated proteins. Phylogenetic analysis based on average nucleotide identity and single nucleotide polymorphisms identified closely related C. coli genomes available in the NCBI database. Taken together, the analyzed genomic data of this potentially virulent strain of C. coli will facilitate further understanding of this important foodborne pathogen most likely leading to better control strategies. The chromosome and plasmid sequences of C. coli YH502 have been deposited in GenBank under the accession numbers CP018900.1 and CP018901.1, respectively.

  6. Noncytotoxic Clostridium perfringens Enterotoxin (CPE) Variants Localize CPE Intestinal Binding and Demonstrate a Relationship between CPE-Induced Cytotoxicity and Enterotoxicity▿

    Science.gov (United States)

    Smedley, James G.; Saputo, Juliann; Parker, Jacquelyn C.; Fernandez-Miyakawa, Mariano E.; Robertson, Susan L.; McClane, Bruce A.; Uzal, Francisco A.

    2008-01-01

    Clostridium perfringens enterotoxin (CPE) causes the symptoms of a very common food poisoning. To assess whether CPE-induced cytotoxicity is necessary for enterotoxicity, a rabbit ileal loop model was used to compare the in vivo effects of native CPE or recombinant CPE (rCPE), both of which are cytotoxic, with those of the noncytotoxic rCPE variants rCPE D48A and rCPE168-319. Both CPE and rCPE elicited significant fluid accumulation in rabbit ileal loops, along with severe mucosal damage that starts at villus tips and then progressively affects the entire villus, including necrosis of epithelium and lamina propria, villus blunting and fusion, and transmural edema and hemorrhage. Similar treatment of ileal loops with either of the noncytotoxic rCPE variants produced no visible histologic damage or fluid transport changes. Immunohistochemistry revealed strong CPE or rCPE168-319 binding to villus tips, which correlated with the abundant presence of claudin-4, a known CPE receptor, in this villus region. These results support (i) cytotoxicity being necessary for CPE-induced enterotoxicity, (ii) the CPE sensitivity of villus tips being at least partially attributable to the abundant presence of receptors in this villus region, and (iii) claudin-4 being an important intestinal receptor for CPE. Finally, rCPE168-319 was able to partially inhibit CPE-induced histologic damage, suggesting that noncytotoxic rCPE variants might be useful for protecting against some intestinal effects of CPE. PMID:18505809

  7. Plasmid-Borne Antimicrobial Resistance of Staphylococcus aureus Isolated in a Hospital in Lisbon, Portugal.

    Science.gov (United States)

    Costa, Sofia Santos; Palma, Cláudia; Kadlec, Kristina; Fessler, Andrea T; Viveiros, Miguel; Melo-Cristino, José; Schwarz, Stefan; Couto, Isabel

    2016-12-01

    Plasmids play a key role in the genetic plasticity and survival of Staphylococcus aureus in challenging environments. Although many S. aureus plasmids have been described, still few studies portray the plasmid content of a given S. aureus population. The aim of this work was to characterize the plasmids carried by a collection of 53 S. aureus isolates collected in a large hospital in Lisbon, Portugal, and investigate their role in conferring resistance to several antimicrobial agents. Plasmids were present in 44 out of the 53 isolates and were grouped into eleven AccI restriction profiles. Plasmid curing of representative strains and comparison of antimicrobial susceptibility profiles between pairs of isogenic strains proved to be a valuable guidance tool in the identification of plasmid-located resistance genes. The plasmids harbored several resistance genes, namely blaZ (resistance to β-lactams), erm(C) (resistance to macrolides, lincosamides, and streptogramin B), cadA (resistance to cadmium and zinc), cadD (resistance to cadmium), and qacA and smr (resistance to biocides and dyes). This study demonstrates the impact of plasmids on the resistance properties of S. aureus, highlighting their role in the dissemination of antibiotic, heavy metal, and biocide resistance genes, and survival of this major pathogen in the hospital environment.

  8. A NOVEL ADAPTIVE ALGORITHM OF CPE CORRECTION FOR OFDM SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    Cai Zejian; Ge Jianhua; Wu Guohang

    2005-01-01

    On the basis of the analysis of the effect of PHase Noise (PHN) and Common Phase Error (CPE) on Orthogonal Frequency Division Multiplexing (OFDM) systems, a cost function is constructed. By the cost function and the idea of Least-Mean-Square (LMS) adaptive algorithm, the adaptive algorithm for the correction of CPE is presented. The simulations have been performed to investigate the performance for tracking PHN and estimating CPE, the results show that the algorithm performs soundly.

  9. CPE OF URANIUM (VI USING IONIC LIQUID

    Directory of Open Access Journals (Sweden)

    SANAA NAÏT-TAHAR

    2016-07-01

    Full Text Available Cloud point extraction (CPE was used to extract uranium (VI from an aqueous solution in acetate media. The methodology used is based on the formation of uranyl-ionic liquid (I complexes and uranyl-D2EHPA soluble in a micellar phase of non-ionic surfactant (Triton X-100. The uranium (VI complexes are then extracted into the surfactant-rich phase at ambient temperature. The ionic liquid (IL used as a chelating agent was synthesized and characterized in this study. It is composed of N-butyl N’-triethoxy methyl imidazolium cation and diethylhexylphosphate (D2EHPA-H as anion. The effect of the IL on the extraction efficiency was studied in presence and in absence of IL’s cation in acetate medium.

  10. The Learning Organization and CPE: Some Philosophical Considerations.

    Science.gov (United States)

    Battersby, David

    1999-01-01

    Continuing professional education (CPE) must assume a new agenda consistent with emancipatory and transformative perspectives of the learning organization. Principles from the work of Gramsci and Freire inform this agenda, focused on the why more than the how of CPE and professional practice. (SK)

  11. Emergence and Spread of Plasmid-Borne tet(B)::ISCR2 in Minocycline-Resistant Acinetobacter baumannii Isolates

    OpenAIRE

    Vilacoba, Elisabet; Almuzara, Marisa; Gulone, Lucía; Traglia, German Matias; Figueroa, Silvia A.; Sly, Gabriela Edith; Fernandez, Analia; Centron, Daniela; Ramirez, Maria Soledad

    2013-01-01

    Resistance to minocycline has emerged in multidrug-resistant Acinetobacter baumannii isolates from Buenos Aires Hospitals. Few reports about the description and dispersion of tet genes were published in this species. We observed the presence of tet(B) in all minocycline resistant isolates. This gene was found associated to the ISCR2 mobile element, which could in part explain its dispersion. Fil: Vilacoba, Elisabet. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Co...

  12. Emergence and Spread of Plasmid-Borne tet(B)::ISCR2 in Minocycline-Resistant Acinetobacter baumannii Isolates

    OpenAIRE

    Vilacoba, Elisabet; Almuzara, Marisa; Gulone, Lucía; Traglia, German Matias; Figueroa, Silvia A.; Sly, Gabriela Edith; Fernandez, Analia; Centron, Daniela; Ramirez, Maria Soledad

    2015-01-01

    Resistance to minocycline has emerged in multidrug-resistant Acinetobacter baumannii isolates from Buenos Aires Hospitals. Few reports about the description and dispersion of tet genes were published in this species. We observed the presence of tet(B) in all minocycline resistant isolates. This gene was found associated to the ISCR2 mobile element, which could in part explain its dispersion. Fil: Vilacoba, Elisabet. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Co...

  13. Comparison of chromogenic media for recovery of carbapenemase-producing enterobacteriaceae (CPE) and evaluation of CPE prevalence at a tertiary care academic medical center.

    Science.gov (United States)

    Pence, Morgan A; Hink, Tiffany; Burnham, Carey-Ann D

    2015-02-01

    We evaluated the performance characteristics of chromID CARBA and HardyCHROM Carbapenemase for the detection of carbapenemase-producing Enterobacteriaceae (CPE). A CPE prevalence study was conducted using chromID CARBA; this demonstrated that in low-prevalence settings, CPE screening agars may lack specificity, and confirmation of putative isolates is necessary.

  14. Claudin-binder C-CPE mutants enhance permeability of insulin across human nasal epithelial cells.

    Science.gov (United States)

    Kojima, Takashi; Kondoh, Masuo; Keira, Takashi; Takano, Ken-Ichi; Kakuki, Takuya; Kaneko, Yakuto; Miyata, Ryo; Nomura, Kazuaki; Obata, Kazufumi; Kohno, Takayuki; Konno, Takumi; Sawada, Norimasa; Himi, Tetsuo

    2016-10-01

    Intranasal insulin administration has therapeutic potential for Alzheimer's disease and in intranasal administration across the nasal mucosa, the paracellular pathway regulated by tight junctions is important. The C-terminal fragment of Clostridium perfringens enterotoxin (C-CPE) binds the tight junction protein claudin and disrupts the tight junctional barrier without a cytotoxic effect. The C-CPE mutant called C-CPE 194 binds only to claudin-4, whereas the C-CPE 194 mutant called C-CPE m19 binds not only to claudin-4 but also to claudin-1. In the present study, to investigate the effects of C-CPE mutants on the tight junctional functions of human nasal epithelial cells (HNECs) and on the permeability of human recombinant insulin across the cells, HNECs were treated with C-CPE 194 and C-CPE m19. C-CPE 194 and C-CPE m19 disrupted the barrier and fence functions without changes in expression of claudin-1, -4, -7, and occludin or cytotoxicity, whereas they transiently increased the activity of ERK1/2 phosphorylation. The disruption of the barrier function caused by C-CPE 194 and C-CPE m19 was prevented by pretreatment with the MAPKK inhibitor U0126. Furthermore, C-CPE 194 and C-CPE m19 significantly enhanced the permeability of human recombinant insulin across HNECs and the permeability was also inhibited by U0126. These findings suggest that C-CPE mutants 194 and m19 can regulate the permeability of insulin across HNECs via the MAPK pathway and may play a crucial role in therapy for the diseases such as Alzheimer's disease via the direct intranasal insulin administration.

  15. Optimization of the use of carbon paste electrodes (CPE for electrochemical study of the chalcopyrite

    Directory of Open Access Journals (Sweden)

    Daniela G. Horta

    2009-01-01

    Full Text Available The use of carbon paste electrodes (CPE of mineral sulfides can be useful for electrochemical studies to overcome problems by using massive ones. Using CPE-chalcopyrite some variables were electrochemically evaluated. These variables were: (i the atmosphere of preparation (air or argon of CPE and elapsed time till its use; (ii scan rate for voltammetric measurements and (iii chalcopyrite concentration in the CPE. Based on cyclic voltammetry, open-circuit potential and electrochemical impedance results the recommendations are: oxygen-free atmosphere to prepare and kept the CPE until around two ours, scan rates from 10 to 40 mV s-1, and chalcopyrite concentrations > 20%.

  16. Truncating Homozygous Mutation of Carboxypeptidase E (CPE in a Morbidly Obese Female with Type 2 Diabetes Mellitus, Intellectual Disability and Hypogonadotrophic Hypogonadism.

    Directory of Open Access Journals (Sweden)

    Suzanne I M Alsters

    Full Text Available Carboxypeptidase E is a peptide processing enzyme, involved in cleaving numerous peptide precursors, including neuropeptides and hormones involved in appetite control and glucose metabolism. Exome sequencing of a morbidly obese female from a consanguineous family revealed homozygosity for a truncating mutation of the CPE gene (c.76_98del; p.E26RfsX68. Analysis detected no CPE expression in whole blood-derived RNA from the proband, consistent with nonsense-mediated decay. The morbid obesity, intellectual disability, abnormal glucose homeostasis and hypogonadotrophic hypogonadism seen in this individual recapitulates phenotypes in the previously described fat/fat and Cpe knockout mouse models, evidencing the importance of this peptide/hormone-processing enzyme in regulating body weight, metabolism, and brain and reproductive function in humans.

  17. The modification of the flexibility of radiation crosslinked PE by blending PE with EVA and CPE

    Science.gov (United States)

    Hui, Zhang; Jiufu, Xu

    1993-07-01

    Polyethylene (PE) is used as an insulation material for wires and cables because of its excellent electrical properties. Most of the properties of PE are improved greatly after irradiation, but, it was harden and split easily in low temperature. According to ethylene-vinyl acetate polymer (EVA) and chlor-poly-ethylene (CPE) possesing good flexibility. Blending of EVA/PE, CPE/PE systems were performed individually. As the results of experiment, suitable radiation dose and percentage of EVA/PE, CPE/PE systems have been determined to overcome the split of heat-shrinking tube after shrinkage.

  18. Necrotizing enterocolitis and death in a goat kid associated with enterotoxin (CPE)-producing Clostridium perfringens type A.

    Science.gov (United States)

    Miyakawa, Mariano E Fernandez; Saputo, Julian; Leger, Judy St; Puschner, Birgit; Fisher, Derek J; McClane, Bruce A; Uzal, Francisco A

    2007-12-01

    A goat kid died after being depressed for several days. No significant gross abnormalities were observed at postmortem examination, while histopathological analysis revealed diffuse necrotizing enterocolitis. Isolation of Clostridium perfringens type A secreting enterotoxin (CPE) and presence of CPE in the small intestine suggest that CPE contributed to the death of this kid.

  19. Necrotizing enterocolitis and death in a goat kid associated with enterotoxin (CPE)-producing Clostridium perfringens type A

    OpenAIRE

    2007-01-01

    A goat kid died after being depressed for several days. No significant gross abnormalities were observed at postmortem examination, while histopathological analysis revealed diffuse necrotizing enterocolitis. Isolation of Clostridium perfringens type A secreting enterotoxin (CPE) and presence of CPE in the small intestine suggest that CPE contributed to the death of this kid.

  20. Emergence of anxiety-like behaviours in depressive-like Cpe(fat/fat) mice.

    Science.gov (United States)

    Rodriguiz, Ramona M; Wilkins, John J; Creson, Thomas K; Biswas, Reeta; Berezniuk, Iryna; Fricker, Arun D; Fricker, Lloyd D; Wetsel, William C

    2013-08-01

    Cpe(fat/fat) mice have a point mutation in carboxypeptidase E (Cpe), an exopeptidase that removes C-terminal basic amino acids from intermediates to produce bioactive peptides. The mutation renders the enzyme inactive and unstable. The absence of Cpe activity in these mutants leads to abnormal processing of many peptides, with elevated levels of intermediates and greatly reduced levels of the mature peptides. Cpe(fat/fat) mice develop obesity, diabetes and infertility in adulthood. We examined whether anxiety- and/or depressive-like behaviours are also present. Anxiety-like responses are not evident in young Cpe(fat/fat) mice (∼60 d), but appear in older animals (>90 d). These behaviours are reversed by acute treatment with diazepam or fluoxetine. In contrast, increased immobilities in forced swim and tail suspension are evident in all age groups examined. These behaviours are reversed by acute administration of reboxetine. In comparison acute treatments with fluoxetine or bupropion are ineffective; however, immobility times are normalized with 2 wk treatment. These data demonstrate that Cpe(fat/fat) mice display depressive-like responses aged ∼60 d, whereas anxiety-like behaviours emerge ∼1 month later. In tail suspension, the reboxetine findings show that noradrenergic actions of antidepressants are intact in Cpe(fat/fat) mice. The ability of acute fluoxetine treatment to rescue anxiety-like while leaving depressive-like responses unaffected suggests that serotonin mechanisms underlying these behaviours are different. Since depressive-like responses in the Cpe(fat/fat) mice are rescued by 2 wk, but not acute, treatment with fluoxetine or bupropion, these mice may serve as a useful model that resembles human depression.

  1. DISRUPTION OF THE SACCHAROMYCES CEREVISIAE GENE FOR NADPH-CYTOCHROME P450-REDUCTASE CAUSES INCREASED SENSITIVITY TO KETOCONAZOLE

    Science.gov (United States)

    Strains of Saccharomyces cerevisiae deleted in the NADPH-cytochrome P450 reductase gene by transplacement are 200-fold more sensitive to ketoconazole, an inhibitor of the cytochrome P450 lanosterol 14-demethylase. Resistance is restored through complementation by the plasmid-born...

  2. Multiple cellular roles of Neurospora crassa plc-1, splA2, and cpe-1 in regulation of cytosolic free calcium, carotenoid accumulation, stress responses, and acquisition of thermotolerance.

    Science.gov (United States)

    Barman, Ananya; Tamuli, Ranjan

    2015-04-01

    Phospholipase C1 (PLC1), secretory phospholipase A2 (sPLA2) and Ca(2+)/H(+) exchanger proteins regulate calcium signaling and homeostasis in eukaryotes. In this study, we investigate functions for phospholipase C1 (plc-1), sPLA2 (splA2) and a Ca(2+)/H(+) exchanger (cpe-1) in the filamentous fungus Neurospora crassa. The Δplc-1, ΔsplA2, and Δcpe-1 mutants exhibited a growth defect on medium supplemented with the divalent ionophore A23187, suggesting that these genes might play a role in regulation of cytosolic free Ca(2+) concentration ([Ca(2+)](c)) in N. crassa. The strains lacking plc-1, splA2, and cpe-1 possessed higher carotenoid content than wild type at 8°C, 22°C, and 30°C, and showed increased ultraviolet (UV)-survival under conditions that induced carotenoid accumulation. Moreover, Δplc-1, ΔsplA2, and Δcpe-1 mutants showed reduced survival rate under hydrogen peroxide-induced oxidative stress and induced thermotolerance after exposure to heat shock temperatures. Thus, this study revealed multiple cellular roles for plc-1, splA2, and cpe-1 genes in regulation of [Ca(2+)](c), carotenoid accumulation, survival under stress conditions, and acquisition of thermotolerance induced by heat shock.

  3. Gene expression and functional annotation of the human and mouse choroid plexus epithelium.

    Directory of Open Access Journals (Sweden)

    Sarah F Janssen

    Full Text Available BACKGROUND: The choroid plexus epithelium (CPE is a lobed neuro-epithelial structure that forms the outer blood-brain barrier. The CPE protrudes into the brain ventricles and produces the cerebrospinal fluid (CSF, which is crucial for brain homeostasis. Malfunction of the CPE is possibly implicated in disorders like Alzheimer disease, hydrocephalus or glaucoma. To study human genetic diseases and potential new therapies, mouse models are widely used. This requires a detailed knowledge of similarities and differences in gene expression and functional annotation between the species. The aim of this study is to analyze and compare gene expression and functional annotation of healthy human and mouse CPE. METHODS: We performed 44k Agilent microarray hybridizations with RNA derived from laser dissected healthy human and mouse CPE cells. We functionally annotated and compared the gene expression data of human and mouse CPE using the knowledge database Ingenuity. We searched for common and species specific gene expression patterns and function between human and mouse CPE. We also made a comparison with previously published CPE human and mouse gene expression data. RESULTS: Overall, the human and mouse CPE transcriptomes are very similar. Their major functionalities included epithelial junctions, transport, energy production, neuro-endocrine signaling, as well as immunological, neurological and hematological functions and disorders. The mouse CPE presented two additional functions not found in the human CPE: carbohydrate metabolism and a more extensive list of (neural developmental functions. We found three genes specifically expressed in the mouse CPE compared to human CPE, being ACE, PON1 and TRIM3 and no human specifically expressed CPE genes compared to mouse CPE. CONCLUSION: Human and mouse CPE transcriptomes are very similar, and display many common functionalities. Nonetheless, we also identified a few genes and pathways which suggest that the CPE

  4. Phylogeny, clinical associations, and diagnostic utility of the pilin subunit gene (sfpA) of sorbitol-fermenting, enterohemorrhagic Escherichia coli O157:H-

    NARCIS (Netherlands)

    Friedrich, Alexander W; Nierhoff, Katja V; Bielaszewska, Martina; Mellmann, Alexander; Karch, Helge

    2004-01-01

    The plasmid-borne sfpA gene encodes the pilin subunit in sorbitol-fermenting (SF) enterohemorrhagic Escherichia coli (EHEC) O157:H-. We investigated the distribution of sfpA among 600 E. coli isolates comprising the complete E. coli standard reference (ECOR) and diarrheagenic E. coli (DEC) strain co

  5. Phylogeny, clinical associations, and diagnostic utility of the pilin subunit gene (sfpA) of sorbitol-fermenting, enterohemorrhagic Escherichia coli O157:H-

    NARCIS (Netherlands)

    Friedrich, Alexander W; Nierhoff, Katja V; Bielaszewska, Martina; Mellmann, Alexander; Karch, Helge

    2004-01-01

    The plasmid-borne sfpA gene encodes the pilin subunit in sorbitol-fermenting (SF) enterohemorrhagic Escherichia coli (EHEC) O157:H-. We investigated the distribution of sfpA among 600 E. coli isolates comprising the complete E. coli standard reference (ECOR) and diarrheagenic E. coli (DEC) strain co

  6. Evaluation of a novel procedure for rapid detection of carbapenemase-producing Enterobacteriaceae (CPE) using the LightMix® modular carbapenemase kits.

    Science.gov (United States)

    Oviaño, Marina; Torres, Isabel; González, Maria; Bou, Germán

    2016-12-01

    Evaluation of the LightMix(®) modular carbapenemase kits for the rapid detection of carbapenemase-producing Enterobacteriaceae (CPE) and the application of these kits to the direct detection of colonized patients and bacteraemias. The modular multiplex PCR kits targeting blaKPC, blaNDM, blaVIM, blaIMP and blaOXA-48-like carbapenem resistance genes were evaluated in terms of sensitivity and specificity for carbapenemase resistance in a set of 118 labelled clinical isolates. Among these, 96 were CPE genotypically characterized by PCR and sequencing. The limits of detection were calculated for the different carbapenem resistance genes in terms of cfu/mL. In addition, the kits were used to evaluate colonization of patients by CPE by comparing this assay with the Xpert(®) Carba-R Kit on 127 rectal, perirectal and pharyngeal samples. Blood cultures from bacteraemias (4) and spiked blood cultures (23) with genotypically characterized isolates were also evaluated. The overall sensitivity and specificity of the multiplex PCR assay was 99% and 100%, respectively. The limit of detection for blaKPC, blaVIM, blaIMP and blaOXA-48-like is 60 cfu/mL and for blaNDM 500 cfu/mL. The colonization and bacteraemia studies revealed a 100% agreement between the results obtained by this assay and the ones obtained by GeneXpert(®). The LightMix(®) modular carbapenemase kits are highly reliable and utilizable assays for both colonized and septic patients, and can help in the improvement of infection control. Their modular design facilitates cost-effective detection of CPE in hospital settings. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  7. Environmental stress cracking of PVC and PVC-CPE - Part III Crack growth

    NARCIS (Netherlands)

    Breen, J.

    1995-01-01

    The fracture toughness of Polyvinylchloride (PVC) and PVC modified with 10% chlorinated polyethylene (PVC-CPE) was studied in vapour and in liquid environments by crack growth measurements on single-edge notch specimens under three-point bending at 23°C. In addition, some results obtained in air at

  8. Preparation of Flame Resistant CPE/EPDM Cable Materials%阻燃型 CPE/EPDM 电缆母料研制

    Institute of Scientific and Technical Information of China (English)

    王波; 汤粤豫; 杨金明

    2015-01-01

    CPE/EPDM cable materials were prepared with CPE and EPDM as raw ma-terials,dicumyl peroxide (DCP)and triallyl isocyanurate (TAIC)as curing agents,white carbon black as reinforcement agent,Al(OH)3 and Mg(OH)2 as flame retardant and with the right amount of plasticizer,stabilizer and age resister.The results show that the vol-ume resistivity of cable materials can be up to 8.843 × 10 1 4 Ω· cm, the breakdown strength is 36.5 kV/mm, the elongation at break is 230% and the tensile strength is 3.88 MPa.The indicators meet the requirements and the performance can meet the need of cable materials.%以氯化聚乙烯/三元乙丙橡胶(CPE/EPDM)作为电缆料的原料,以过氧化二异丙苯(DCP)/三烯丙基氰尿酸酯(TAIC)为硫化剂,白炭黑为补强剂,Al(OH)3和 Mg(OH)2作为阻燃剂,并配以适量的增塑剂、稳定剂和防老剂,制备阻燃绝缘电缆料。经测试,电缆料的体积电阻率可达到8.843×1014Ω·cm,击穿强度为36.5 kV/mm,断裂伸长率为230%,拉伸强度为3.88 MPa。各项指标达到要求,性能满足电缆料需要。

  9. 耐低温CPE/EPDM护套配方研究%Investigation of the Formulation of Low Temperature Resistant CPE/EPDM Sheath

    Institute of Scientific and Technical Information of China (English)

    尚德义; 王启丰; 王强; 潘龙

    2012-01-01

    研究了适用于低温条件下使用的电缆护套材料,从基体材料的选择、配合剂的选择、工艺加工等方面进行了探讨.对护套性能进行了测定,实验结果表明,所研制的CPE/EPDM护套材料耐低温性能优良,工艺性能满足生产要求,可以作为风力发电用电缆护套使用.

  10. Claudins Overexpression in Ovarian Cancer: Potential Targets for Clostridium Perfringens Enterotoxin (CPE Based Diagnosis and Therapy

    Directory of Open Access Journals (Sweden)

    Diana P. English

    2013-05-01

    Full Text Available Claudins are a family of tight junction proteins regulating paracellular permeability and cell polarity with different patterns of expression in benign and malignant human tissues. There are approximately 27 members of the claudin family identified to date with varying cell and tissue-specific expression. Claudins-3, -4 and -7 represent the most highly differentially expressed claudins in ovarian cancer. While their exact role in ovarian tumors is still being elucidated, these proteins are thought to be critical for ovarian cancer cell invasion/dissemination and resistance to chemotherapy. Claudin-3 and claudin-4 are the natural receptors for the Clostridium perfringens enterotoxin (CPE, a potent cytolytic toxin. These surface proteins may therefore represent attractive targets for the detection and treatment of chemotherapy-resistant ovarian cancer and other aggressive solid tumors overexpressing claudin-3 and -4 using CPE-based theranostic agents.

  11. Non-enzymatic glucose sensor based on electrodeposited copper on carbon paste electrode (Cu/CPE)

    Energy Technology Data Exchange (ETDEWEB)

    Nurani, Dita Arifa, E-mail: d.arifa@sci.ui.ac.id; Wibowo, Rahmat; Fajri, Iqbal Farhan El [Department of Chemistry, FMIPA, Universitas Indonesia, Kampus UI Depok (Indonesia)

    2016-04-19

    The development of non-enzymatic glucose sensor has much attention due to their applications in glucose monitoring. In this research, copper oxide is used as a non-enzymatic glucose sensor by oxidizing glucose to gluconolactone. Copper was electrodeposited on Carbon paste electrode (CPE) at constant potential. The experimental condition was varied in electrodeposition of Cu with the following parameters: Electrodeposition time 60 s, 120 s and 180 s and potential reduction -0.166 V, -0.266 V and -0.366 V. The effective performance of these working electrodes in sensing glucose was investigated. The Cu/CPE which used -0.366 V potential reduction and 120 s electrodeposition time shows the best performance. The amperometric response current in concentration range 1.6-62.5 mM of glucose gives the good linearity R{sup 2} = 0.9988, low detection limit 0.6728 mM and high sensitivity 1183.59 µA mM{sup −1}cm{sup −2}. Furthermore this sensor exhibited a good repeatability with %RSD = 1.31% (n=10) and high stability with %RSD = 1.51% (n=5 days). The homogeneity of Cu particles on CPE was investigated by Scanning Electron Microscope (SEM).

  12. Characterization of the Basic Operational Properties of the Capillary Plasma Electrode (CPE) Discharge

    Science.gov (United States)

    Lopez, Jose; Zhu, Weidong; Figus, Margaret; Becker, Kurt

    2008-10-01

    Various approaches have been pursued to create stable atmospheric pressure discharges by extending the lifetime of the diffuse phase of the discharge to hundreds of microseconds. Previous research showed that the stability of the diffuse mode is dependent on the frequency (in the kHz range), gas type, power, mode of the excitation, and geometrical confinement. The Capillary Plasma Electrode (CPE) discharge is able to produce stable atmospheric pressure nonequilibrium plasmas. The CPE is similar in design to a barrier-electrode discharge, but has perforated dielectrics. This configuration, aside from exhibiting a diffuse mode of operation, also exhibits the so-called ``capillary jet'' mode, in which the capillaries ``turn on'' and a bright plasma jet emerges from the capillaries. The capillary jets from adjacent capillaries overlap so that the discharge appears uniform when the electrode contains an array of holes. There appears to be a threshold frequency for the capillary jet formation, which is strongly dependent on the L/D ratio of the capillaries, where D is the diameter of a capillary and L its length. This current work explores these modes of operation of the CPE by characterizing the electrical and optical emission properties of this discharge.

  13. FLAME RETARDANCE FUNCTION OF IFR TO TPU/CPE%IFR对TPU/CPE体系的阻燃作用

    Institute of Scientific and Technical Information of China (English)

    郭玉花; 赵鸣山

    2005-01-01

    采用国产热塑性聚氨酯弹性体(TPU)、氯化聚乙烯(CPE)在TPU/CPE二元共混改性体系的基础上,添加自行复配研制的膨胀型阻燃剂(IFR),对所构成的TPU/CPE/IFR进行了研究.结果表明:TPU/CPE/IFR阻燃体系阻燃性可达到FV-0级(IFR为19.2份),并具有较好的力学性能;该阻燃体系的拉伸强度、断裂伸长率分别保持了TPU/CPE的56%和73%.TPV/CPE/IFR体系随着IFR用量的增加,流动性变好.

  14. Altered Murine Tissue Colonization by Borrelia burgdorferi following Targeted Deletion of Linear Plasmid 17-Carried Genes

    OpenAIRE

    Casselli, Timothy; Tourand, Yvonne; Bankhead, Troy

    2012-01-01

    The causative agent of Lyme disease, Borrelia burgdorferi, possesses a segmented genome comprised of a single linear chromosome and upwards of 23 linear and circular plasmids. Much of what is known about plasmid-borne genes comes from studying laboratory clones that have spontaneously lost one or more plasmids during in vitro passage. Some plasmids, including the linear plasmid lp17, are never or rarely reported to be lost during routine culture; therefore, little is known about the requireme...

  15. First identification of a chromosomally located penicillinase gene in Kingella kingae species isolated in continental Europe.

    Science.gov (United States)

    Basmaci, Romain; Bidet, Philippe; Berçot, Béatrice; Jost, Christelle; Kwon, Thérésa; Gaumetou, Elodie; Bonacorsi, Stéphane

    2014-10-01

    Kingella kingae is the major pathogen causing osteoarticular infections (OAI) in young children in numerous countries. Plasmid-borne TEM-1 penicillinase production has been sporadically detected in a few countries but not in continental Europe, despite a high prevalence of K. kingae infections. We describe here for the first time a K. kingae β-lactamase-producing strain in continental Europe and demonstrate the novel chromosomal location of the blaTEM-1 gene in K. kingae species.

  16. First Identification of a Chromosomally Located Penicillinase Gene in Kingella kingae Species Isolated in Continental Europe

    OpenAIRE

    Basmaci, Romain; Bidet, Philippe; Berçot, Béatrice; Jost, Christelle; Kwon, Thérésa; Gaumetou, Elodie; Bonacorsi, Stéphane

    2014-01-01

    Kingella kingae is the major pathogen causing osteoarticular infections (OAI) in young children in numerous countries. Plasmid-borne TEM-1 penicillinase production has been sporadically detected in a few countries but not in continental Europe, despite a high prevalence of K. kingae infections. We describe here for the first time a K. kingae β-lactamase-producing strain in continental Europe and demonstrate the novel chromosomal location of the blaTEM-1 gene in K. kingae species.

  17. Study of the operational properties of the Capillary Plasma Electrode (CPE) discharges

    Science.gov (United States)

    Lopez, Jose; Jacome, David; Zhu, Wei-Dong; Figus, Margaret; Becker, Kurt H.

    2009-03-01

    Various approaches have been pursued to create stable atmospheric pressure discharges by extending the lifetime of the diffuse phase of the discharge to hundreds of microseconds. Previous research showed that the stability of the diffuse mode is dependent on the frequency (in the kHz range), gas type power, mode of the excitation, and geometrical confinement. Some of the most promising approaches are based on the recognition of the arc formation in high-pressure plasmas can be avoided and stable high-pressure plasma can be generated and maintained when the plasma are spatially constricted to the dimensions of tens to hundreds of microns. The Capillary Plasma Electrode (CPE) discharge is stable to produce stable atmospheric pressure nonequilibrium plasma. The CPE is similar in design to the Barrier Electrode Discharge, but has perforated dielectrics. The configuration, aside from exhibiting a diffuse mode of operation, also exhibits the so-called ``capillary jet'' mode, in which the capillaries “turn on” and a bright plasma jet emerges from the capillaries. The capillary jets from adjacent capillaries overlap so that the discharge appears uniform when the electrode contains an array of holes. There appears to be a threshold frequency for the capillary jet formation, which is strongly dependent on the L/D ratio of the capillaries, where D is diameter of the capillary and L its length. However, the operating principles and basic properties of this behavior are not well understood. The current work explores these modes of operations of the CPE by characterizing the electrical and optical emission properties of this discharge by examining a multi-hole discharge as well as a single capillary discharge reactor.

  18. Synthesis of histone proteins by CPE ligation using a recombinant peptide as the C-terminal building block.

    Science.gov (United States)

    Kawakami, Toru; Yoshikawa, Ryo; Fujiyoshi, Yuki; Mishima, Yuichi; Hojo, Hironobu; Tajima, Shoji; Suetake, Isao

    2015-11-01

    The post-translational modification of histones plays an important role in gene expression. We report herein on a method for synthesizing such modified histones by ligating chemically prepared N-terminal peptides and C-terminal recombinant peptide building blocks. Based on their chemical synthesis, core histones can be categorized as two types; histones H2A, H2B and H4 which contain no Cys residues, and histone H3 which contains a Cys residue(s) in the C-terminal region. A combination of native chemical ligation and desulphurization can be simply used to prepare histones without Cys residues. For the synthesis of histone H3, the endogenous Cys residue(s) must be selectively protected, while keeping the N-terminal Cys residue of the C-terminal building block that is introduced for purposes of chemical ligation unprotected. To this end, a phenacyl group was successfully utilized to protect endogenous Cys residue(s), and the recombinant peptide was ligated with a peptide containing a Cys-Pro ester (CPE) sequence as a thioester precursor. Using this approach it was possible to prepare all of the core histones H2A, H2B, H3 and H4 with any modifications. The resulting proteins could then be used to prepare a core histone library of proteins that have been post-translationally modified.

  19. Determination of cadmium at ultra-trace levels by CPE-molecular fluorescence combined methodology

    Energy Technology Data Exchange (ETDEWEB)

    Talio, Maria Carolina [Instituto de Quimica de San Luis (INQUISAL-CONICET), Chacabuco y Pedernera, 5700 San Luis (Argentina); Luconi, Marta O. [Area de Quimica Analitica, Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis, San Luis (Argentina); Masi, Adriana N. [Area de Bromatologia- Ensayo y Valoracion de Medicamentos, Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis, San Luis (Argentina); Instituto de Quimica de San Luis (INQUISAL-CONICET), Chacabuco y Pedernera, 5700 San Luis (Argentina); Fernandez, Liliana P., E-mail: lfernand@unsl.edu.ar [Area de Quimica Analitica, Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis, San Luis (Argentina); Instituto de Quimica de San Luis (INQUISAL-CONICET), Chacabuco y Pedernera, 5700 San Luis (Argentina)

    2009-10-15

    A highly sensitive micelle-mediated extraction methodology for the preconcentration and determination of trace levels of cadmium by molecular fluorescence has been developed. Metal was complexed with o-phenanthroline (o-phen) and eosin (eo) at pH 7.6 in buffer Tris medium and quantitatively extracted into a small volume of surfactant-rich phase of PONPE 7.5 after centrifugating. The chemical variables affecting cloud point extraction (CPE) were evaluated and optimized. The RSD for six replicates of cadmium determinations at 0.84 {mu}g L{sup -1} level was 1.17%. The linearity range using the preconcentration system was between 2.79 x 10{sup -3} {mu}g L{sup -1} and 2.81 {mu}g L{sup -1} with a correlation coefficient of 0.99. Under the optimal conditions, it obtained a LOD of 8.38 x 10{sup -4} {mu}g L{sup -1} and LOQ of 2.79 x 10{sup -3} {mu}g L{sup -1}. The method presented good sensitivity and selectivity and was applied to the determination of trace amounts of cadmium in commercially bottled mineral water, tap water and water well samples with satisfactory results. The proposed method is an innovative application of CPE-luminescence to metal analysis comparable in sensitivity and accuracy with atomic spectroscopies.

  20. The interplay between relatedness and horizontal gene transfer drives the evolution of plasmid-carried public goods.

    Science.gov (United States)

    Mc Ginty, Sorcha É; Lehmann, Laurent; Brown, Sam P; Rankin, Daniel J

    2013-06-22

    Plasmids carry a wide range of genes that are often involved in bacterial social behaviour. The question of why such genes are frequently mobile has received increasing attention. Here, we use an explicit population genetic approach to model the evolution of plasmid-borne bacterial public goods production. Our findings highlight the importance of both transmission and relatedness as factors driving the evolution of plasmid-borne public goods production. We partition the effects of plasmid transfer of social traits into those of infectivity and the effect of increased relatedness. Our results demonstrate that, owing to its effect on relatedness, plasmid mobility increases the invasion and stability of public goods, in a way not seen in individually beneficial traits. In addition, we show that plasmid transfer increases relatedness when public goods production is rare but this effect declines when production is common, with both scenarios leading to an increase in the frequency of plasmid-borne public goods. Plasmids remain important vectors for the spread of social genes involved in bacterial virulence thus an understanding of their dynamics is highly relevant from a public health perspective.

  1. Five phosphonate operon gene products as components of a multi-subunit complex of the carbon-phosphorus lyase pathway

    DEFF Research Database (Denmark)

    Jochimsen, Bjarne; Lolle, Signe; McSorley, Fern R.

    2011-01-01

    by expression in E. coli and purification of Phn-polypeptides. PhnG, PhnH, PhnI, PhnJ, and PhnK copurify as a protein complex by ion-exchange, size-exclusion, and affinity chromatography. The five polypeptides also comigrate in native-PAGE. Cross-linking of the purified protein complex reveals a close proximity...... is suggested to be PhnG4H2I2J2K. Deletion of individual phn genes reveals that a strain harboring plasmid-borne phnGHIJ produces a protein complex consisting of PhnG, PhnH, PhnI, and PhnJ, whereas a strain harboring plasmid-borne phnGIJK produces a protein complex consisting of PhnG and PhnI. We conclude...

  2. Critical Point Facility (CPE) Group in the Spacelab Payload Operations Control Center (SL POCC)

    Science.gov (United States)

    1992-01-01

    The primary payload for Space Shuttle Mission STS-42, launched January 22, 1992, was the International Microgravity Laboratory-1 (IML-1), a pressurized manned Spacelab module. The goal of IML-1 was to explore in depth the complex effects of weightlessness of living organisms and materials processing. Around-the-clock research was performed on the human nervous system's adaptation to low gravity and effects of microgravity on other life forms such as shrimp eggs, lentil seedlings, fruit fly eggs, and bacteria. Materials processing experiments were also conducted, including crystal growth from a variety of substances such as enzymes, mercury iodide, and a virus. The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Featured is the Critical Point Facility (CPE) group in the SL POCC during STS-42, IML-1 mission.

  3. Effect of Processing Technic on Damping Properties and Microstructures of CPE/AO2246 Composites%加工工艺对CPE/AO2246阻尼性能与形态结构的影响

    Institute of Scientific and Technical Information of China (English)

    姜生; 张慧萍; 晏雄; 蔡永东

    2012-01-01

    利用氯化聚乙烯(CPE)与有机小分子2,2亚甲基-双(4-甲基-6-叔丁基苯酚)(AO2246)采用不同工艺制备了有机杂化阻尼材料,通过动态力学分析(DMA)、差示扫描量热(DSC)、扫描电镜(SEM)和红外光谱(FT-IR)考察了材料的动态力学性能和微观结构。研究结果表明,AO2246在基体CPE中的分散状态对体系的阻尼性能影响较大。在未经热压的CPE/AO2246体系中,AO2246以三维谷粒结晶存在,造成体系的损耗因子(tanδ)比基体的还要低;而经过热压工艺的CPE/AO2246体系,AO2246与CPE产生了有机杂化,使体系的tanδ峰值获得较大的提高,同时玻璃化温度向高温方向移动,改善了体系的阻尼特性。红外光谱图表明,高温热压工艺的AO2246分子间产生了氢键作用的新的吸收峰,从而进一步提高了体系的阻尼性能。%The dynamic mechanical properties and microstructure of composites consisting of chlorinated polyethylene(CPE) and 2,2′-methylene-bis-(6-tert-butyl-4-methyl-phenol)(AO2246) were investigated by means of dynamic mechanical analysis(DMA),differential scanning calorimetry(DSC),scanning electron microscope(SEM) and Fourier transform infrared spectroscopy(FT-IR).The results show that dispersion states of AO2246 in CPE matrix have an important influence on the damping properties of CPE/AO2246 system.In unpressed CPE/AO2246 composite,most AO2246 moleculars exist in the form of crystals with three-dimensional grain shape,which lead to lower loss factor(tanδ) of unpressed CPE/AO2246 than that of pure CPE.Whereas organic hybrid of CPE and AO2246 is formed after hot-pressed and quenching process in pressed CPE/AO2246 system,which makes loss factor(tanδ) obtain improvement and glass transition temperature shift to higher temperature.In two varied hot-pressed process,it is seen that pressed CPE/AO2246 at higher temperature exhibits a new absorption peak from

  4. Speaking of "Competence": Toward a Cross-Translation for Human Resource Development (HRD) and Continuing Professional Education (CPE)

    Science.gov (United States)

    Jeris, Laurel; Johnson, Kathleen

    2004-01-01

    This paper compares and contrasts literature on competence that resides in the disciplines of HRD and CPE. Definitions, Purposes, Assessments and Achievements related to the competence conceptual framework are examined for contextual cues and connections between theory and practice in an effort to contribute to greater dialog and interdisciplinary…

  5. Measurements of Rotational Temperatures in Atmospheric-Pressure Capillary Plasma Electrode (CPE) Discharge

    Science.gov (United States)

    Figus, Margaret; Abramzon, Nina; Becker, Kurt

    2003-10-01

    We report the results of rotational temperature measurements in atmospheric-pressure capillary plasma electrode (CPE) discharges in ambient air using the unresolved N2 second positive band. Assuming that the emitting N2 molecules can be described by a Maxwell-Boltzmann distribution characterized by a single rotational temperature, this temperature is determined from a fit of the measured emission spectrum to a calculated spectrum. If the emitting species are in equilibrium with the bulk gas in the plasma, then this temperature can be interpreted as the gas kinetic temperature in the plasma. We determined rotational temperatures for three different plasma regions: inside the capillary by analyzing radiation emitted along the axis of the capillary, between the capillaries, and perpendicular to the axis of the capillary. Each region has a different plasma density and, therefore, a different gas temperature with the plasma inside the capillary being the hottest. We also measured the rotational temperatures in each region as a function of the plasma power. As expected, the rotational temperatures increase with increasing discharge power. Work supported by the NSF and by ARO through a DURIP award.

  6. Voltammetric Study and Determination of Phenylephrine Hydrochloride at INP-Nafion-Modified CPE Sensor Employing Differential Pulse Voltammetry

    Directory of Open Access Journals (Sweden)

    Zeinab Pourghobadi

    2014-03-01

    Full Text Available In this study, describes the voltammetric oxidation and determination of phenylephrine (PHE hydrochloride at a new chemically modified electrode. Iron nanoparticle (INPs was dispersed in Nafion solution to obtain a INP-Nafion-modified CPE for the voltammetric analysis of PHE .The electrochemical behaviour of PHE on INP-Nafion-modified CPE was studied, using cyclic voltammetry as a diagnostic technique. The effects of amount of INPs-Nafion dispersion, pH, and scan rate on the response of modified electrode for the oxidation of PHE were investigated. Using differential pulse voltammetry (DPV, the modified electrode indicated a dynamic linear range for quantitative determination of PHE in the range of 5 μM−130 μM, and the detection limit was estimated to be 0.76 μM. The method was developed for the determination of PHE in pharmaceutical samples with satisfactory results.

  7. NIa-Pro of Papaya ringspot virus interacts with Carica papaya eukaryotic translation initiation factor 3 subunit G (CpeIF3G).

    Science.gov (United States)

    Gao, Le; Tuo, Decai; Shen, Wentao; Yan, Pu; Li, Xiaoying; Zhou, Peng

    2015-02-01

    The interaction of papaya eukaryotic translation initiation factor 3 subunit G (CpeIF3G) with Papaya ringspot virus (PRSV) NIa-Pro was validated using a bimolecular fluorescence complementation assay in papaya protoplasts based on the previous yeast two-hybrid assay results. The C-terminal (residues 133-239) fragment of PRSV NIa-Pro and the central domain (residues 59-167) of CpeIF3G were required for effective interaction between NIa-Pro and CpeIF3G as shown by a Sos recruitment yeast two-hybrid system with several deletion mutants of NIa-Pro and CpeIF3G. The central domain of CpeIF3G, which contains a C2HC-type zinc finger motif, is required to bind to other eIFs of the translational machinery. In addition, quantitative real-time reverse transcription PCR assay confirmed that PRSV infection leads to a 2- to 4.5-fold up-regulation of CpeIF3G mRNA in papaya. Plant eIF3G is involved in various stress response by enhancing the translation of resistance-related proteins. It is proposed that the NIa-Pro-CpeIF3G interaction may impair translation preinitiation complex assembly of defense proteins and interfere with host defense.

  8. Phylogenetic analysis of bacterial and archaeal arsC gene sequences suggests an ancient, common origin for arsenate reductase

    Directory of Open Access Journals (Sweden)

    Dugas Sandra L

    2003-07-01

    Full Text Available Abstract Background The ars gene system provides arsenic resistance for a variety of microorganisms and can be chromosomal or plasmid-borne. The arsC gene, which codes for an arsenate reductase is essential for arsenate resistance and transforms arsenate into arsenite, which is extruded from the cell. A survey of GenBank shows that arsC appears to be phylogenetically widespread both in organisms with known arsenic resistance and those organisms that have been sequenced as part of whole genome projects. Results Phylogenetic analysis of aligned arsC sequences shows broad similarities to the established 16S rRNA phylogeny, with separation of bacterial, archaeal, and subsequently eukaryotic arsC genes. However, inconsistencies between arsC and 16S rRNA are apparent for some taxa. Cyanobacteria and some of the γ-Proteobacteria appear to possess arsC genes that are similar to those of Low GC Gram-positive Bacteria, and other isolated taxa possess arsC genes that would not be expected based on known evolutionary relationships. There is no clear separation of plasmid-borne and chromosomal arsC genes, although a number of the Enterobacteriales (γ-Proteobacteria possess similar plasmid-encoded arsC sequences. Conclusion The overall phylogeny of the arsenate reductases suggests a single, early origin of the arsC gene and subsequent sequence divergence to give the distinct arsC classes that exist today. Discrepancies between 16S rRNA and arsC phylogenies support the role of horizontal gene transfer (HGT in the evolution of arsenate reductases, with a number of instances of HGT early in bacterial arsC evolution. Plasmid-borne arsC genes are not monophyletic suggesting multiple cases of chromosomal-plasmid exchange and subsequent HGT. Overall, arsC phylogeny is complex and is likely the result of a number of evolutionary mechanisms.

  9. The urease gene cluster of Vibrio parahaemolyticus does not influence the expression of the thermostable direct hemolysin (TDH) gene or the TDH-related hemolysin gene.

    Science.gov (United States)

    Nakaguchi, Yoshitsugu; Okuda, Jun; Iida, Tetsuya; Nishibuchi, Mitsuaki

    2003-01-01

    In order to investigate why the thermostable direct hemolysin (TDH) and the TDH-related hemolysin (TRH) of Vibrio parahaemolyticus are produced at low levels from urease-positive strains, the effect of the functional urease gene cluster of V. parahaemolyticus on the expression of the tdh and trh genes was examined. Transcriptional lacZ fusions with the tdh1, tdh2, trh1 and trh2 genes representing variants of the tdh and trh genes were integrated into the chromosome of an Escherichia coli strain and a urease-negative V. parahaemolyticus strain. The plasmid-borne urease gene cluster introduced and expressed in these constructs did not affect expression of any of the fusion genes. The amount of TDH produced from a Kanagawa phenomenon-positive V. parahaemolyticus did not change by introduction of the urease gene cluster either. It was concluded therefore that the urease gene cluster is not involved in the regulation of tdh and trh expression.

  10. PVC/CPE/nano-CaCO3复合材料的性能研究%Performance study on PVC/CPE/nano-CaCO3 composite material

    Institute of Scientific and Technical Information of China (English)

    王玉龙; 杨琳; 王勇; 陈勤; 丁武绿; 李振中

    2015-01-01

    通过熔融共混法制备了不同配方含量的PVC/CPE/nano-CaCO3复合材料,并对其力学性能、耐热性能和热性能进行了分析,研究了不同碳酸钙含量对复合材料的拉伸强度、冲击强度、维卡软化点温度和热分解温度的影响规律.

  11. Determination of trace amounts of Brown HT as a food dye by a CPE-scanometry method

    Directory of Open Access Journals (Sweden)

    A. Shokrollahi

    2017-01-01

    Full Text Available In this study, trace amounts of Brown HT were extracted, pre-concentrated and determined by cloud point extraction-scanometry (CPE-scanometry as a simple, fast and inexpensive method. The procedure is based on CPE of Brown HT from an aqueous solution, diluting the extracted surfactant-rich phase with ethanol to 500 μL, transferring the appropriate volume to Plexiglas® cells and scanning the cells. Then, the colour of each cell was analyzed by software written in visual basic (VB 6 into red, green and blue values. Effective parameters for the extraction efficiency, such as the pH of the system, the concentration of surfactant, the equilibration temperature and equilibration time, were investigated and optimized. Under optimal conditions, the calibration curve was linear in the range of 0.06–2.60 mg L−1. The detection limit of the proposed method was 0.04 mg L−1. In addition, the effects of some foreign species, including cations, anions and dyes, were investigated. The method was applied successfully for the determination of Brown HT in some water samples.

  12. Multiplex Real-Time PCR Assay for Detection and Classification of Klebsiella pneumoniae Carbapenemase Gene (blaKPC) Variants▿

    OpenAIRE

    Chen, Liang; Mediavilla, José R.; Endimiani, Andrea; Rosenthal, Marnie E.; Zhao, Yanan; Robert A Bonomo; Kreiswirth, Barry N.

    2011-01-01

    Carbapenem resistance mediated by plasmid-borne Klebsiella pneumoniae carbapenemases (KPC) is an emerging problem of significant clinical importance in Gram-negative bacteria. Multiple KPC gene variants (blaKPC) have been reported, with KPC-2 (blaKPC-2) and KPC-3 (blaKPC-3) associated with epidemic outbreaks in New York City and various international settings. Here, we describe the development of a multiplex real-time PCR assay using molecular beacons (MB-PCR) for rapid and accurate identific...

  13. The Impact of the Rate and Variety of Uses of Fixed and Mobile Broadband on the Progress of CPE: A Chartered Accountant's Perspective

    Science.gov (United States)

    Rawashdeh, Awni; Al-namlah, Lamia

    2015-01-01

    To examine the impact of the usage of fixed and mobile broadband on the progress of continuing professional education (CPE) from the perspective of chartered accountants in Saudi Arabia, an e-mail survey was conducted. A random sampling of chartered accountants in Saudi Arabia was investigated. This research was aimed to identify any correlation…

  14. The locus theologicus of U.S. Hispanic/Latino/a Theology and its implications for Clinical Pastoral Education (CPE) curriculum development.

    Science.gov (United States)

    Meza, Francis Rivers

    2005-01-01

    The author examines the history of theological method based on the term locus theologicus, the refinement of this method by Liberation Theologians and U. S. Hispanic/Latino/a Theologians, and describes one experience of using contextual theology to develop curriculum for Second-Year Clinical Pastoral Education (CPE) Residents.

  15. Whole-body distribution and radiation dosimetry of the dopamine transporter radioligand [{sup 11}C]PE2I in healthy volunteers

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Maria-Joao [Service Hospitalier Frederic Joliot, Institut d' Imagerie Biomedicale, Direction des Sciences du Vivant, Commissariat a l' Energie Atomique, F-91406 Orsay (France)]. E-mail: maria-joao.ribeiro@cea.fr; Ricard, Marcel [Service de Physique, Institut Gustave Roussy, 39 rue Camille Desmoulins, 94805 Villejuif (France); Lievre, Marie-Angele [Service Hospitalier Frederic Joliot, Institut d' Imagerie Biomedicale, Direction des Sciences du Vivant, Commissariat a l' Energie Atomique, F-91406 Orsay (France); Bourgeois, Sandrine [Service Hospitalier Frederic Joliot, Institut d' Imagerie Biomedicale, Direction des Sciences du Vivant, Commissariat a l' Energie Atomique, F-91406 Orsay (France); Emond, Patrick [INSERM U316, Laboratoire de Biophysique medicale et pharmaceutique, UFR des Sciences Pharmaceutiques, 37200 Tours (France); Gervais, Philippe [Service Hospitalier Frederic Joliot, Institut d' Imagerie Biomedicale, Direction des Sciences du Vivant, Commissariat a l' Energie Atomique, F-91406 Orsay (France); Dolle, Frederic [Service Hospitalier Frederic Joliot, Institut d' Imagerie Biomedicale, Direction des Sciences du Vivant, Commissariat a l' Energie Atomique, F-91406 Orsay (France); Syrota, Andre [Service Hospitalier Frederic Joliot, Institut d' Imagerie Biomedicale, Direction des Sciences du Vivant, Commissariat a l' Energie Atomique, F-91406 Orsay (France)

    2007-05-15

    Introduction: This study reports on the biodistribution and radiation dosimetry of a cocaine analog, the (E)-N-(3-iodoprop-2-enyl)-2{beta}-carbomethoxy-3{beta}-(4'-tolyl)nortropane (PE2I), labeled with carbon 11 ([{sup 11}C]PE2I). [{sup 11}C]PE2I is used in positron emission tomography (PET) for examination of the dopamine neuronal transporter (DAT). DAT radioligands are often used to evaluate the progression of Parkinson's disease or the efficiency of neuroprotective therapeutics, and, typically, these studies required several successive PET scans. Methods: In three healthy male volunteers, whole-body scans were performed up to 2 h following intravenous injection of 321{+-}6 MBq of [{sup 11}C]PE2I. For each subject, regions of interest were defined over all visible organs to generate time-activity curves and calculate the percentage of injected activity. Time-activity data were fitted to a monoexponential model, as an uptake phase followed by a mono-exponential washout, or bi-exponential model to obtain residence times. With the use of the MIRD method, several source organs were considered in estimating residence time and mean effective radiation absorbed doses. Results: Blood pressure and ECG findings remained unchanged after radioligand injection. The primary route of clearance was renal. Ten minutes after injection, high activities were observed in the kidneys, urinary-bladder, stomach, liver, salivary glands and brain. The urine bladder wall, stomach and liver received the highest absorbed doses. The average effective dose of [{sup 11}C]PE2I was estimated to be 6.4{+-}0.6 {mu}Sv/MBq. Conclusion: The amount of [{sup 11}C]PE2I required for adequate DAT PET imaging results in an acceptable effective dose equivalent permitting two or three repeated cerebral PET studies, with the injection of 222 MBq for each study.

  16. 重组融合蛋白C-CPE-ETA′对卵巢癌细胞的细胞毒作用%Target-specific cytotoxic activity of recombinant fusion toxin C-CPE-ETA′ against CLDN-3, 4-overexpressing ovarian cancer cells

    Institute of Scientific and Technical Information of China (English)

    姚勤; 郑庆梅; 温君凤; 吕腾; 魏明谦; 戴淑真

    2010-01-01

    Objective The aim of this study was to explore the possibility of creating a toxin,C-CPE-ETA′, by fusing C-terminal high affinity binding domain of CPE(C-CPE)with a truncated form of Pseudomonas aeruginosa exotoxin A(ETA')and to examine whether C-CPE-ETA' could specifically target CLDN-3,4 molecule and the targeted toxin was cytotoxic against CLDN-3,4-overexpressing ovarian cancer.Methods CLDN-3 and CLDN-4 expressions were analyzed at the mRNA level in three ovarian cancer cell liues and epithelial ovarian cancer tissues from 20 patients. After transforming an expression plasmid of C-CPE-ETA′ into E. coli BL21(DE3)plysS strain, the recombinant protein was purified using His-Bind resin chromatography column and analyzed by Western blot and Coomassie blue staining. The specific binding, proapoptotic and cytolytic activities were evaluated by flow cytometry, fluorescence microscopy with the JC-1 probe and MTT assay in CLDN-3,4-overexpressing ovarian cancer cells. Results Quantitive RT-PCR results showed there existed high levels of CLDN-3 and CLDN-4 in ovarian cancer cells, CAOV3,OVCAR3 and SKOV3. Moreover, high expressions of CLDN-3 and CLDN-4 were observed in 90.0%(18/20)and 60.0%(12/20)of ovarian cancer tissues, with an expression level 10-fold higher than that in the normal ovarian tissue. A 58 000 recombinant protein C-CPE-ETA′ was demonstrated by Western blot and Coomassie blue staining. Purified and recombinant C-CPE-ETA' was bound with high affinity to CLDN-3,4-overexpressing ovarian cancer cells, CAOV3, OVCAR3 and SKOV3 cells. C-CPE-ETA′ was strongly proapoptotic and cytotoxic towards the CLDN-3,4-overexpressing ovarian cancer cells. The concentration of IC50 was 7. 364 ng/ml for CAOV3 cells, 8.110 ng/ml for OVCAR3 cells and 22. 340 ng/ml for SKOV3cells, respectively. However, control CLDN-3,4-deficient cell line HUVEC was not susceptible to the recombinant C-CPE-ETA' at a concentration up to 10 μg/ml. Conclusions The C-CPE-ETA' protein exhibits

  17. Frequency of biocide-resistant genes and susceptibility to chlorhexidine in high-level mupirocin-resistant, methicillin-resistant Staphylococcus aureus (MuH MRSA).

    Science.gov (United States)

    Liu, Qingzhong; Zhao, Huanqiang; Han, Lizhong; Shu, Wen; Wu, Qiong; Ni, Yuxing

    2015-08-01

    The aim of this study was to determine the prevalence of biocide-resistant determinants and the susceptibility to chlorhexidine in high-level mupirocin-resistant, methicillin-resistant Staphylococcus aureus (MuH MRSA). Fifty-three MuH MRSA isolates were analyzed for plasmid-borne genes (qacA/B, smr, qacG, qacH, and qacJ) by polymerase chain reaction (PCR); for chromosome-mediated genes (norA, norB, norC, mepA, mdeA, sepA, and sdrM) by PCR and quantitative reverse transcription-PCR (qRT-PCR); and for susceptibility to chlorhexidine by MIC and minimum bactericidal concentration (MBC). Furthermore, disinfectant efficacy was tested in the presence of 3.0% bovine serum albumin (BSA) in MBC detection. The plasmid-borne genes qacA/B (83.0%) and smr (77.4%) and overexpressions of chromosome-mediated genes norA (49.0%) and norB (28.8%) were predominantly found in isolates studied, and 90.6% of the isolates revealed tolerance to chlorhexidine. In the presence of BSA, the average MBC of chlorhexidine for these isolates rose to 256 μg/mL. Altogether, our results suggest that surveillance of sensitivity to biocides among MuH MRSA isolates is essential for hospital infection control.

  18. Synthesis and Structure Control of A New Kind of Inelastomer Impact Modifier with Core-shell Structure and Impact Modification to PVC/CPE

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A new kind of inelastomer impact modifier with a core-shell structure was synthesized by employing a multi-step composite emulsion polymerization technique, the size and morphology structure of the core-shell particles could be controlled by the multi-step composite emulsion polymerization technique. The study of the impact strength and the elongation at break of the PVC/CPE blend with different contents of core-shell particles(C-S) indicated that the mechanical properties of PVC/CPE/C-S composite were the best when the concentration of the particle was 2.5%(mass fraction) which showed the different regularities and characteristics of elastomer toughening plastic.

  19. Muusikamaailm : CPE Bachi käsikirjad tagasi Saksamaale. Täna uusooper Londonis. Theodorakise ooperid plaadil. David Golub lahkunud. Preemia Palle Mikkelborgile / Priit Kuusk

    Index Scriptorium Estoniae

    Kuusk, Priit, 1938-

    2001-01-01

    Ukraina nõustus tagastama Saksamaale C.P.E. Bachi muusikakäsikirjad, mis Nõukogude Liidu armee sealt II Maailmasõja ajal ära viis. Inglise Rahvusooperis lavastuvast D.Saweri ooperist "From Morning to Midnight". M.Theodorakise kolm ooperit (antiiktriloogia "Elektra", "Antigone" ja "Medeia") ilmusid seoses maestro 75. juubeliga kaheksal CD-plaadil. Lühidalt D.Golubist. Põhjamaade Nõukogu tänavuse muusikapreemia võitis P.Mikkelborg

  20. Detection and prevalence of pathogenic Yersinia enterocolitica in refrigerated and frozen dairy products by duplex PCR and dot hybridization targeting the virF and ail genes.

    Science.gov (United States)

    Ye, Y W; Ling, N; Han, Y J; Wu, Q P

    2014-11-01

    Pathogenic Yersinia enterocolitica is involved in yersiniosis through expression of chromosome-borne or plasmid-borne virulence factors. Yersinia enterocolitica is a cold-tolerant pathogen frequently isolated from refrigerated or frozen foods. However, little attention has been focused on the prevalence of pathogenic Y. enterocolitica in refrigerated or frozen dairy samples in China. In this study, we developed a new duplex PCR targeting the plasmid-borne virF gene and chromosome-borne ail gene for detection of pathogenic Y. enterocolitica isolates. We established a detection limit for the duplex PCR of 6.5 × 10(2)cfu/mL in artificially contaminated dairy samples. In addition, the duplex PCR could detect directly 4.5 to 5.7 cfu of Y. enterocolitica in 5 mL of brain heart infusion broth after 6 h of enrichment at 28 °C. A newly developed dot hybridization assay further confirmed specificity of the duplex PCR for detection of virulent Y. enterocolitica. Furthermore, 13 Y. enterocolitica and 5 pathogenic strains, from 88 commercial frozen or refrigerated dairy products, were detected successfully by the China National Standard method (GB/T4789.8-2008) and the duplex PCR, respectively. Finally, biotypes and serotypes of pathogenic Y. enterocolitica strains were further characterized. The duplex PCR developed here is reliable for large-scale screening, routine monitoring, and risk assessment of pathogenic Y. enterocolitica in refrigerated or frozen dairy products.

  1. 外在因素对TiO2膜电极/溶液界面CPE行为的影响%Effect of Extrinsic Factors on the CPE Behavior of Film TiO2 Electrode

    Institute of Scientific and Technical Information of China (English)

    郭源; 李永军; 夏熙; 张校刚; 何茂霞

    2001-01-01

    Under ideally polarizable conditions, TiO2 film electrode/solution electrolyte interface exhibited frequency dispersion, The effects of external factors such as the concentration of KNO3, various electrolytes and applied potentials near the flat band potential on the CPE behavior of TiO2 film electrode were studied in electrolyte solution by using A.C. impedance spectra. It was found that concentration of KNO3 had a significant effect on the CPE exponent n only when the concentration is smaller than 0.1 mol· L- 1. In this concentration range, the CPE exponent n went up with increase of KNO3 concentration, once the concentration was larger than this value, however, the CPE exponent n approached to a constant, irrelevant of the concentration. Near the flat band potential, the influence of applied potential on the exponent n depended on the selected frequency range. When the frequency was in lower range, that is smaller than 0.1 Hz, this influence was obvious,on the other hand, it bore no relation to applied potential in higher frequency. Types of electrolytes only affected the CPE constant Q, having nothing to do with the CPE exponentn.

  2. Positively regulated glycerol/G3P-dependent Bacillus subtilis gene expression system based on anti-termination.

    Science.gov (United States)

    Lewin, Anna; Su, Xiao-Dong; Hederstedt, Lars

    2009-01-01

    Plasmid pLALA was constructed for glycerol or glycerol-3-phosphate inducible plasmid-borne gene expression in Bacillus subtilis and closely related Gram-positive bacteria. Gene expression using pLALA is based on anti-termination of transcription and involves the B. subtilis GlpP protein that in the presence of glycerol-3-phosphate acts as an anti-terminator protein by binding to the 5'-untranslated region of glpD mRNA. Properties and the usefulness of the system, denoted LALA, were validated by inducible production in B. subtilis strains of two water-soluble proteins (beta-galactosidase and a protein phospho-tyrosine phosphatase), and one integral membrane protein (heme A synthase). Advantages with LALA is that it is based on positive control, does not involve a DNA-binding protein, and that glycerol, a cheap and stable compound, can be used as inducer of gene expression.

  3. Damping Properties of Piezoelectric and Electrical Conductive of BaTiO3/VGCF/CPE Composites: Effect of Carbon Fiber

    Institute of Scientific and Technical Information of China (English)

    晏雄; 张慧萍; 住田雅夫

    2001-01-01

    A new damping composite of CPE/BaTiO3/VGCF has been developed on the basis of the piezo- effect and conductivity mechanism. The conductivity of composites varied with the VGCF content are tested and analyzed.The results indicate that the conductivity of composites grows up slowly as the VGCF content is in the range of 10%-20%. It is very useful for industrial application to control the conductivity of composites by adjusting the VGCF content. In addition, at the range of - 50 - 120°C,the dependence of loss factor on the VGCF content varied with the temperature are tested and analyzed by dynamic mechanical and dielectric behavior measurement of the composites, and expected results are obtained.

  4. Evolution of the iss gene in Escherichia coli.

    Science.gov (United States)

    Johnson, Timothy J; Wannemuehler, Yvonne M; Nolan, Lisa K

    2008-04-01

    The increased serum survival gene iss has long been recognized for its role in extraintestinal pathogenic Escherichia coli (ExPEC) virulence. iss has been identified as a distinguishing trait of avian ExPEC but not of human ExPEC. This gene has been localized to large virulence plasmids and shares strong similarities with the bor gene from bacteriophage lambda. Here, we demonstrate that three alleles of iss occur among E. coli isolates that appear to have evolved from a common lambda bor precursor. In addition to the occurrence of iss on the ColV/BM virulence plasmids, at least two iss alleles occur within the E. coli chromosome. One of these alleles (designated type 3) was found to occur in the genomes of all currently sequenced ExPEC strains on a similar prophage element that also harbors the Sit iron and manganese transport system. When the prevalence of the three iss types was examined among 487 E. coli isolates, the iss type 3 gene was found to occur at a high frequency among ExPEC isolates, irrespective of the host source. The plasmid-borne iss allele (designated type 1) was highly prevalent among avian pathogenic E. coli and neonatal meningitis-associated E. coli isolates but not among uropathogenic E. coli isolates. This study demonstrates the evolution of iss in E. coli and provides an additional tool for discriminating among E. coli pathotypes through the differentiation of the three iss allele types and bor.

  5. Conjugative multi-resistant plasmids in Haihe River and their impacts on the abundance and spatial distribution of antibiotic resistance genes.

    Science.gov (United States)

    Dang, Bingjun; Mao, Daqing; Xu, Yan; Luo, Yi

    2017-03-15

    In this study, five classes of antibiotic resistance genes (ARGs) were quantified in sediment samples of Haihe River, China, with abundance ranging from 1.39 × 10(4) to 1.58 × 10(10) copies/g dry weight. Meanwhile, antibiotic resistant conjugative plasmids were also isolated from these samples through filter mating assays. In total, 202 transconjugants were isolated and tested for their antibiotic resistance phenotypes, among which 26 different types of conjugative plasmids were observed. The majority of these plasmids showed a multi-resistant phenotype and the most prevalent resistance was tetracycline resistance and sulfonamide resistance. Furthermore, we tested the transfer frequencies of these plasmids, determined their genotypes and then compared the plasmid-borne ARGs with their corresponding abundance in Haihe River. Most of the isolated plasmids exhibited high transfer frequencies to the recipient strain Escherichia coli J53. Plasmids isolated from the urban areas of Haihe River have higher transfer frequencies than the rural areas. Results from comprehensive analysis of plasmid genotypes, ARG abundance and plasmid sequencing confirmed that most of the plasmid-borne ARGs were the dominant genes in the Haihe River. Therefore, conjugative plasmids isolated from the Haihe River plays a crucial role in the dissemination, abundance and spatial distribution of ARGs in Haihe River, especially some unfrequent ARGs like blaGES-1. This study will help to increase the knowledge on the conjugative plasmid-mediated ARG propagation in the environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. CPE进化教学法在涉外文秘实训课堂教学中的应用%Application of CPE evolution pedagogy in Practice of Foreign-oriented Secretary course

    Institute of Scientific and Technical Information of China (English)

    钟小立

    2015-01-01

    According to the principle of CPE evolution pedagogy this paper points out that the application of CPE evolution pedagogy can effectively solve the problems in the practice of foreign⁃oriented secretary course taught by the traditional methods. CPE evolution pedagogy integrates the case pedagogy project pedagogy and evolution theory as one. This paper introduces its four advantages over the traditional single pedagogy and how to utilize the new pedagogy to design the teaching of practice of foreign⁃oriented secretary course as well as the matters needing attention while applying for it.%选用CPE进化教学法,旨在其可以有效解决传统涉外文秘实训课堂中教与学中普遍存在的问题,根据CPE进化教学法的理论原理,结合教学实践中的具体做法,对涉外文秘实训教学改革进行分析和思考。

  7. Determination of trace nickel in textiles with CPE-GFAAS%浊点萃取-石墨炉原子吸收法测定纺织品中微量镍

    Institute of Scientific and Technical Information of China (English)

    刘德驹; 仓金顺

    2011-01-01

    采用人工汗液浸泡-浊点萃取(CPE)-石墨炉原子吸收光谱法(GFAAS)测定纺织品中微量镍,探讨了影响浊点萃取及测定灵敏度的因素.在最佳条件下,镍的富集倍率为 20 倍,检出限为 0.5 ng/mL(n=11),回收率为 98.0%~102.5%,RSD 小于 2.8%(n=5),镍含量在1.0~500.0 ng/mL 时服从比尔定律.%The combined method of synthetic perspiration dipping, cloud point extraction ( CPE) and graphite furnace atomic absorption spectrometry ( GFAAS) is applied to determine trace nickel in textiles. Factors exerting influence on CPE and detecting sensitivity are analyzed. Under the optimized conditions, this method can be used for determination of trace nickel in textiles with enrichment factor of 20 times, detection limit of 0.5 ng/mL ( n = 11) , recovery rate of 98.0%~102.5%, relative standard deviation( RSD )less than 2.8% (n =5) , the nickel content obeys the Lamber-beer' s law in the range from 1.0 to 500.0 ng/mL.

  8. Plasmid selection in Escherichia coli using an endogenous essential gene marker

    Directory of Open Access Journals (Sweden)

    Good Liam

    2008-08-01

    Full Text Available Abstract Background Antibiotic resistance genes are widely used for selection of recombinant bacteria, but their use risks contributing to the spread of antibiotic resistance. In particular, the practice is inappropriate for some intrinsically resistant bacteria and in vaccine production, and costly for industrial scale production. Non-antibiotic systems are available, but require mutant host strains, defined media or expensive reagents. An unexplored concept is over-expression of a host essential gene to enable selection in the presence of a chemical inhibitor of the gene product. To test this idea in E. coli, we used the growth essential target gene fabI as the plasmid-borne marker and the biocide triclosan as the selective agent. Results The new cloning vector, pFab, enabled selection by triclosan at 1 μM. Interestingly, pFab out-performed the parent pUC19-ampicillin system in cell growth, plasmid stability and plasmid yield. Also, pFab was toxic to host cells in a way that was reversed by triclosan. Therefore, pFab and triclosan are toxic when used alone but in combination they enhance growth and plasmid production through a gene-inhibitor interaction. Conclusion The fabI-triclosan model system provides an alternative plasmid selection method based on essential gene over-expression, without the use of antibiotic-resistance genes and conventional antibiotics.

  9. A ketoreductase gene from Streptomyces mycarofaciens 1748 DNA involved in biosynthesis of a spore pigment

    Institute of Scientific and Technical Information of China (English)

    夏焕章; 王以光

    1997-01-01

    An efficient plasmid transformation system for S. mycarofaciens 1748 has been established. In order to determine the function of MKR gene in S. mycarofaciens 1748, the gene disruption experiment was carried out. For this purpose the plasmid pKC1139 was used. A recombinant strain with white spore appeared, in contrast to the grey-colour spore of S. mycarofaciens 1748. This suggested that homologous recombination between plasmid-borne MKR gene sequence and the chromosome of S. mycarofaciens 1748 had occurred. A Southern hybridization experiment using α- P-labelled MKR gene as probe indicated that the desired integration event had occurred in the re-combinant. The result of gene disruption showed that the alteration of this gene in the chromosome of S. mycarofa-ciens 1748 made sporulating colonies remain white instead of taking on the typical grey colour of sporulating wild type colonies, suggesting that MKR gene is involved in the biosynthesis of a spore pigment. The recombinant strain was in-cubated wit

  10. Esophageal cancer related gene-4 is a choroid plexus-derived injury response gene: evidence for a biphasic response in early and late brain injury.

    Directory of Open Access Journals (Sweden)

    Sonia Podvin

    Full Text Available By virtue of its ability to regulate the composition of cerebrospinal fluid (CSF, the choroid plexus (CP is ideally suited to instigate a rapid response to traumatic brain injury (TBI by producing growth regulatory proteins. For example, Esophageal Cancer Related Gene-4 (Ecrg4 is a tumor suppressor gene that encodes a hormone-like peptide called augurin that is present in large concentrations in CP epithelia (CPe. Because augurin is thought to regulate senescence, neuroprogenitor cell growth and differentiation in the CNS, we evaluated the kinetics of Ecrg4 expression and augurin immunoreactivity in CPe after CNS injury. Adult rats were injured with a penetrating cortical lesion and alterations in augurin immunoreactivity were examined by immunohistochemistry. Ecrg4 gene expression was characterized by in situ hybridization. Cell surface augurin was identified histologically by confocal microscopy and biochemically by sub-cellular fractionation. Both Ecrg4 gene expression and augurin protein levels were decreased 24-72 hrs post-injury but restored to uninjured levels by day 7 post-injury. Protein staining in the supraoptic nucleus of the hypothalamus, used as a control brain region, did not show a decrease of auguin immunoreactivity. Ecrg4 gene expression localized to CPe cells, and augurin protein to the CPe ventricular face. Extracellular cell surface tethering of 14 kDa augurin was confirmed by cell surface fractionation of primary human CPe cells in vitro while a 6-8 kDa fragment of augurin was detected in conditioned media, indicating release from the cell surface by proteolytic processing. In rat CSF however, 14 kDa augurin was detected. We hypothesize the initial release and proteolytic processing of augurin participates in the activation phase of injury while sustained Ecrg4 down-regulation is dysinhibitory during the proliferative phase. Accordingly, augurin would play a constitutive inhibitory function in normal CNS while down

  11. Natural transformation with synthetic gene cassettes: new tools for integron research and biotechnology.

    Science.gov (United States)

    Gestal, Alicia M; Liew, Elissa F; Coleman, Nicholas V

    2011-12-01

    Integrons are genetic elements that can capture and express genes packaged as gene cassettes. Here we report new methods that allow integrons to be studied and manipulated in their native bacterial hosts. Synthetic gene cassettes encoding gentamicin resistance (aadB) and green fluorescence (gfp), or lactose metabolism (lacZY), were made by PCR and self-ligation, converted to large tandem arrays by multiple displacement amplification, and introduced into Escherichia coli or Pseudomonas stutzeri strains via electroporation or natural transformation. Recombinants (Gm(R) or Lac(+)) were obtained at frequencies ranging from 10(1) to 10(6) c.f.u. (µg DNA)(-1). Cassettes were integrated by site-specific recombination at the integron attI site in nearly all cases examined (370/384), including both promoterless and promoter-containing cassettes. Fluorometric analysis of gfp-containing recombinants revealed that expression levels from the integron-associated promoter P(C) were five- to 10-fold higher in the plasmid-borne integron In3 compared with the P. stutzeri chromosomal integrons. Integration of lacZY cassettes into P. stutzeri integrons allowed the bacteria to grow on lactose, and the lacZY gene cassette was stably maintained in the absence of selection. This study is believed to be the first to show natural transformation by gene cassettes, and integron-mediated capture of catabolic gene cassettes.

  12. Altered murine tissue colonization by Borrelia burgdorferi following targeted deletion of linear plasmid 17-carried genes.

    Science.gov (United States)

    Casselli, Timothy; Tourand, Yvonne; Bankhead, Troy

    2012-05-01

    The causative agent of Lyme disease, Borrelia burgdorferi, possesses a segmented genome comprised of a single linear chromosome and upwards of 23 linear and circular plasmids. Much of what is known about plasmid-borne genes comes from studying laboratory clones that have spontaneously lost one or more plasmids during in vitro passage. Some plasmids, including the linear plasmid lp17, are never or rarely reported to be lost during routine culture; therefore, little is known about the requirement of these conserved plasmids for infectivity. In this study, the effects of deleting regions of lp17 were examined both in vitro and in vivo. A mutant strain lacking the genes bbd16 to bbd25 showed no deficiency in the ability to establish infection or disseminate to the bloodstream of mice; however, colonization of peripheral tissues was delayed. Despite the ability to colonize ear, heart, and joint tissues, this mutant exhibited a defect in bladder tissue colonization for up to 56 days postinfection. This phenotype was not observed in immunodeficient mice, suggesting that bladder colonization by the mutant strain was inhibited by an adaptive immune-based mechanism. Moreover, the mutant displayed increased expression of outer surface protein C in vitro, which was correlated with the absence of the gene bbd18. To our knowledge, this is the first report involving genetic manipulation of lp17 in an infectious clone of B. burgdorferi and reveals for the first time the effects of lp17 gene deletion during murine infection by the Lyme disease spirochete.

  13. nodSU, two new nod genes of the broad host range Rhizobium strain NGR234 encode host-specific nodulation of the tropical tree Leucaena leucocephala.

    Science.gov (United States)

    Lewin, A; Cervantes, E; Chee-Hoong, W; Broughton, W J

    1990-01-01

    Rhizobium species strain NGR234 nodulates at least 35 diverse genera of legumes as well as the nonlegume Parasponia andersonii. Most nodulation genes are located on the 500-kilobase pair symbiotic plasmid, pNGR234a. Previously, three plasmid-borne host range determinants (HsnI, HsnII, and HsnIII) were identified by their ability to extend the nodulation capacity of heterologous rhizobia to include Vigna unguiculata. In this study, we show that HsnII contains two new nod-box linked hsn genes, nodS and nodU.nodS controls nodulation of the tropical tree Leucaena leucocephala, while the nodSU genes regulate nodulation of the pasture legume Desmodium intortum and the grain legume V. unguiculata. Regulation of the nod-box upstream of nodSU by the flavonoid naringenin was shown using a fusion with a promoterless lacZ gene. Determination of the nucleotide sequence of the nodS gene did not reveal homology with any gene in the EMBL library, although Bradyrhizobium japonicum USDA110 contains both nodS and nodU (M. Göttfert, S. Hitz, and H. Hennecke, Molecular Plant-Microbe Interactions 3:308-316, 1990). We suggest that broad host range in NGR234 is controlled in part by a nodD gene which interacts with a wide range of flavonoids, and in part by host-specific nod genes such as nodS.

  14. Position effect on expression of dsd genes cloned onto multicopy plasmids.

    Science.gov (United States)

    Carothers, A M; Heincz, M C; McFall, E

    1980-04-01

    In the D-serine deaminase system of Escherichia coli, which is regulated by positive control, we have fouand a complete lack of trans activation in vivo with multicopy dsd hybrid plasmids. A PLASmid carrying the regulatory gene, dsdC+, did not promote expression of chromosomal dsdCO+A+ loci, nor did a chromosomal dsdC+ gene promote expression of plasmid-borne dsdC delta O+A+ (dsd regulatory gene negative) restriction fragments. However, hybrid plasmids that comprise the entire dsd system (dsdC+O+A+) are highly inducible for the enzyme. These dsd hybrid plasmid deoxyribonucleic acids functioned well as templates in the in vitro coupled transcription-translation system. In vitro-synthesized dsdC+ protein promoted expression of the dsdA+ operation efficiently. Exogenously purified dsdC+ protein also activated expression of several dsdC delta O+A+ plasmid deoxyribonucleic acid templates in vitro. An explanation that reconciles these results with previous dominance studies is presented.

  15. Plasticized Effect of Plasticizers on CPE Waterproofing Materials%增塑剂对氯化聚乙烯防水卷材增塑效果的研究

    Institute of Scientific and Technical Information of China (English)

    王新星; 苑会林; 李明昆

    2012-01-01

    分析了几种增塑剂[邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二辛酯(DOP)、邻苯二甲酸二异癸酯(DIDP)、癸二酸二辛酯(DOS)、偏苯三甲酸三辛酯(TOTM)以及氯化石蜡等]对氯化聚乙烯(CPE)防水卷材的增塑机理.在保持其他条件不变的前提下,选取增塑剂的份数为25份,并在此基础上从力学性能、耐温性能、流变性能以及微观结构四个方面比较各种增塑剂与CPE树脂的相容性,从而比较它们的增塑效果.结果表明:DSC以及电镜结果显示邻苯类增塑剂效果明显优于其他类型增塑剂;其中DOP为主增塑剂的体系综合性能最好;DOS作为主增塑剂时具有良好的耐低温析出性;DIDP作为主增塑剂时具有耐高温析出性;氯化石蜡可作为辅助增塑剂;以上增塑剂可根据各自特点复配使用.%The plasticizing mechanism of several plasticizers (DBP, DOP, DIDP, DOS, TOTM and chlorinated paraffin wax, etc,) to the chlorinated polyethylene (CPE) waterproofing materials was studied. Keeping other conditions under the same basis, the test selected the number of copies of plasticizer as 25. On this basis test compared the compatibility of these plasticizers and the CPE resin from mechanical properties, heat resistance, rheological properties and microstructure of the four aspects, inorder to compare the difference of plasticizing effect. DSC and SEM showed that the plastic effect of phthalic acid ester plasticizer was much better than other types of plasticizer, and the plastic effect of DOP was the best. When DOS was as the main plasticizer it can provide the material better low temperature resistance ability. If DIDP was as the main plasticizer it can provide the material better high temperature resistance ability. Chlorinated paraffin wax cannot be used as main plasticizer but as auxiliary plasticizer. These plasticizers can be used together according to their characteristics.

  16. Investigation on prevalence of Escherichia coli strains carrying virulence genes ipaH, estA, eaeA and bfpA isolated from different water sources

    Directory of Open Access Journals (Sweden)

    Reza Ranjbar

    2016-04-01

    Full Text Available Objective: To investigate prevalence of Escherichia coli (E. coli strains carrying virulence genes ipaH, estA, eaeA and bfpA, isolated from different water sources in Alborz Province. Methods: This study was carried out in 2014. The research included all E. coli strains isolated from different surface water sources in Alborz Province of Iran. E. coli isolates were detected and identified by standard microbiological and biochemical tests. The strains were evaluated for the presence of virulence genes ipaH, estA, eaeA and bfpA by PCR using specific primers. The PCR amplicons were visualized via electrophoresis and stained with ethidium bromide. Results: One hundred E. coli strains were isolated and included in the study. The PCR results showed that 97% of the strains harbored ipaH gene. Moreover, estA, eaeA and bfpA genes were found in 37%, 31% and 3% of the isolates. Conclusions: Our finding showed that the prevalence rates of virulence genes ipaH and estA were very high among E. coli strains isolated from different surface water sources in Alborz Province. Considering their plasmid-borne nature, the risk of transmission of these genes between other bacterial species could pose a high threat to public health.

  17. Allelic variation of bile salt hydrolase genes in Lactobacillus salivarius does not determine bile resistance levels.

    LENUS (Irish Health Repository)

    Fang, Fang

    2009-09-01

    Commensal lactobacilli frequently produce bile salt hydrolase (Bsh) enzymes whose roles in intestinal survival are unclear. Twenty-six Lactobacillus salivarius strains from different sources all harbored a bsh1 allele on their respective megaplasmids. This allele was related to the plasmid-borne bsh1 gene of the probiotic strain UCC118. A second locus (bsh2) was found in the chromosomes of two strains that had higher bile resistance levels. Four Bsh1-encoding allele groups were identified, defined by truncations or deletions involving a conserved residue. In vitro analyses showed that this allelic variation was correlated with widely varying bile deconjugation phenotypes. Despite very low activity of the UCC118 Bsh1 enzyme, a mutant lacking this protein had significantly lower bile resistance, both in vitro and during intestinal transit in mice. However, the overall bile resistance phenotype of this and other strains was independent of the bsh1 allele type. Analysis of the L. salivarius transcriptome upon exposure to bile and cholate identified a multiplicity of stress response proteins and putative efflux proteins that appear to broadly compensate for, or mask, the effects of allelic variation of bsh genes. Bsh enzymes with different bile-degrading kinetics, though apparently not the primary determinants of bile resistance in L. salivarius, may have additional biological importance because of varying effects upon bile as a signaling molecule in the host.

  18. Gene

    Data.gov (United States)

    U.S. Department of Health & Human Services — Gene integrates information from a wide range of species. A record may include nomenclature, Reference Sequences (RefSeqs), maps, pathways, variations, phenotypes,...

  19. Bacterial Toxins for Oncoleaking Suicidal Cancer Gene Therapy.

    Science.gov (United States)

    Pahle, Jessica; Walther, Wolfgang

    For suicide gene therapy, initially prodrug-converting enzymes (gene-directed enzyme-producing therapy, GDEPT) were employed to intracellularly metabolize non-toxic prodrugs into toxic compounds, leading to the effective suicidal killing of the transfected tumor cells. In this regard, the suicide gene therapy has demonstrated its potential for efficient tumor eradication. Numerous suicide genes of viral or bacterial origin were isolated, characterized, and extensively tested in vitro and in vivo, demonstrating their therapeutic potential even in clinical trials to treat cancers of different entities. Apart from this, growing efforts are made to generate more targeted and more effective suicide gene systems for cancer gene therapy. In this regard, bacterial toxins are an alternative to the classical GDEPT strategy, which add to the broad spectrum of different suicide approaches. In this context, lytic bacterial toxins, such as streptolysin O (SLO) or the claudin-targeted Clostridium perfringens enterotoxin (CPE) represent attractive new types of suicide oncoleaking genes. They permit as pore-forming proteins rapid and also selective toxicity toward a broad range of cancers. In this chapter, we describe the generation and use of SLO as well as of CPE-based gene therapies for the effective tumor cell eradication as promising, novel suicide gene approach particularly for treatment of therapy refractory tumors.

  20. Three classes of plasmid (47-63 kb) carry the type B neurotoxin gene cluster of group II Clostridium botulinum.

    Science.gov (United States)

    Carter, Andrew T; Austin, John W; Weedmark, Kelly A; Corbett, Cindi; Peck, Michael W

    2014-08-01

    Pulsed-field gel electrophoresis and DNA sequence analysis of 26 strains of Group II (nonproteolytic) Clostridium botulinum type B4 showed that 23 strains carried their neurotoxin gene cluster on a 47-63 kb plasmid (three strains lacked any hybridization signal for the neurotoxin gene, presumably having lost their plasmid). Unexpectedly, no neurotoxin genes were found on the chromosome. This apparent constraint on neurotoxin gene transfer to the chromosome stands in marked contrast to Group I C. botulinum, in which neurotoxin gene clusters are routinely found in both locations. The three main classes of type B4 plasmid identified in this study shared different regions of homology, but were unrelated to any Group I or Group III plasmid. An important evolutionary aspect firmly links plasmid class to geographical origin, with one class apparently dominant in marine environments, whereas a second class is dominant in European terrestrial environments. A third class of plasmid is a hybrid between the other two other classes, providing evidence for contact between these seemingly geographically separated populations. Mobility via conjugation has been previously demonstrated for the type B4 plasmid of strain Eklund 17B, and similar genes associated with conjugation are present in all type B4 plasmids now described. A plasmid toxin-antitoxin system pemI gene located close to the neurotoxin gene cluster and conserved in each type B4 plasmid class may be important in understanding the mechanism which regulates this unique and unexpected bias toward plasmid-borne neurotoxin genes in Group II C. botulinum type B4.

  1. The Formula Research of EPDM and CPE Common Insulation for Rubber Cable%橡套电缆用EPDM与CPE共用绝缘橡皮的配方研究

    Institute of Scientific and Technical Information of China (English)

    田维生

    2015-01-01

    The paper researched the insulation property of rubber cable,discussed the basic material system and ingredient system selection,confirmed the insulation rubber pre-production formula,tested insulation rubber property. The test result showed that the formula of EPDM and CPE common insulation fulfill the rubber cable mechanical property,processing property and production requirement.%研究了满足橡套电缆使用的绝缘橡皮的性能特点;探讨了基体材料体系、配合剂体系的选择;试验并确定了绝缘橡皮的中试配方;放线生产并检测了绝缘橡皮的性能。实验结果表明:研制的橡套电缆用EPDM与CPE共用绝缘橡皮,其力学性能、工艺性能均满足橡套电缆使用及生产要求。

  2. Three phylogenetic groups of nodA and nifH genes in Sinorhizobium and Mesorhizobium isolates from leguminous trees growing in Africa and Latin America.

    Science.gov (United States)

    Haukka, K; Lindström, K; Young, J P

    1998-02-01

    The diversity and phylogeny of nodA and nifH genes were studied by using 52 rhizobial isolates from Acacia senegal, Prosopis chilensis, and related leguminous trees growing in Africa and Latin America. All of the strains had similar host ranges and belonged to the genera Sinorhizobium and Mesorhizobium, as previously determined by 16S rRNA gene sequence analysis. The restriction patterns and a sequence analysis of the nodA and nifH genes divided the strains into the following three distinct groups: sinorhizobia from Africa, sinorhizobia from Latin America, and mesorhizobia from both regions. In a phylogenetic tree also containing previously published sequences, the nodA genes of our rhizobia formed a branch of their own, but within the branch no correlation between symbiotic genes and host trees was apparent. Within the large group of African sinorhizobia, similar symbiotic gene types were found in different chromosomal backgrounds, suggesting that transfer of symbiotic genes has occurred across species boundaries. Most strains had plasmids, and the presence of plasmid-borne nifH was demonstrated by hybridization for some examples. The nodA and nifH genes of Sinorhizobium teranga ORS1009T grouped with the nodA and nifH genes of the other African sinorhizobia, but Sinorhizobium saheli ORS609T had a totally different nodA sequence, although it was closely related based on the 16S rRNA gene and nifH data. This might be because this S. saheli strain was originally isolated from Sesbania sp., which belongs to a different cross-nodulation group than Acacia and Prosopis spp. The factors that appear to have influenced the evolution of rhizobial symbiotic genes vary in importance at different taxonomic levels.

  3. Sequential expression of bacterial virulence and plant defense genes during infection of tomato with Clavibacter michiganensis subsp. michiganensis.

    Science.gov (United States)

    Chalupowicz, L; Cohen-Kandli, M; Dror, O; Eichenlaub, R; Gartemann, K-H; Sessa, G; Barash, I; Manulis-Sasson, S

    2010-03-01

    The molecular interactions between Clavibacter michiganensis subsp. michiganensis and tomato plant were studied by following the expression of bacterial virulence and host-defense genes during early stages of infection. The C. michiganensis subsp. michiganensis genes included the plasmid-borne cellulase (celA) and the serine protease (pat-1), and the serine proteases chpC and ppaA, residing on the chp/tomA pathogenicity island (PAI). Gene expression was measured following tomato inoculation with Cmm382 (wild type), Cmm100 (lacking the plasmids pCM1 and pCM2), and Cmm27 (lacking the PAI). Transcriptional analysis revealed that celA and pat-1 were significantly induced in Cmm382 at initial 12 to 72 h, whereas chpC and ppaA were highly expressed only 96 h after inoculation. Interdependence between the expression of chromosomal and of plasmid-located genes was revealed: expression of celA and pat-1 was substantially reduced in the absence of the chp/tomA PAI, whereas chpC and ppaA expressions were reduced in the absence of the virulence plasmids. Transcription of chromosomal genes involved in cell wall degradation (i.e., pelA1, celB, xysA, and xysB), was also induced at early stages of infection. Expression of the host-defense genes, chitinase class II and pathogenesis-related protein-5 isoform was induced in the absence of the PAI at early stages of infection, suggesting that PAI-located genes are involved in suppression of tomato basal defenses.

  4. Roles of export genes cgmA and lysE for the production of L-arginine and L-citrulline by Corynebacterium glutamicum.

    Science.gov (United States)

    Lubitz, Dorit; Jorge, João M P; Pérez-García, Fernando; Taniguchi, Hironori; Wendisch, Volker F

    2016-10-01

    L-arginine is a semi-essential amino acid with application in cosmetic, pharmaceutical, and food industries. Metabolic engineering strategies have been applied for overproduction of L-arginine by Corynebacterium glutamicum. LysE was the only known L-arginine exporter of this bacterium. However, an L-arginine-producing strain carrying a deletion of lysE still accumulated about 10 mM L-arginine in the growth medium. Overexpression of the putative putrescine and cadaverine export permease gene cgmA was shown to compensate for the lack of lysE with regard to L-arginine export. Moreover, plasmid-borne overexpression of cgmA rescued the toxic effect caused by feeding of the dipeptide Arg-Ala to lysE-deficient C. glutamicum and argO-deficient Escherichia coli strains. Deletion of the repressor gene cgmR improved L-arginine titers by 5 %. Production of L-lysine and L-citrulline was not affected by cgmA overexpression. Taken together, CgmA may function as an export system not only for the diamine putrescine and cadaverine but also for L-arginine. The major export system for L-lysine and L-arginine LysE may also play a role in L-citrulline export since production of L-citrulline was reduced when lysE was deleted and improved by 45 % when lysE was overproduced.

  5. 浊点萃取-火焰原子吸收法(CPE-FAAS)测定蜂蜜中痕量锰%Determination of trace manganese in honey by cloud point extracton-flame absorption spectrometry

    Institute of Scientific and Technical Information of China (English)

    杜军良; 尤海霞; 胡杨; 王秀峰

    2013-01-01

    A new method for determination of trace manganese (Ⅱ) in honey by flame atomic absorption spectrometry combined with cloud point extraction was developed.The cloud point extraction system was based on TritonX-100 as surfactant and 8-Oxyquinoline as complexing agent.The parameters affecting cloud point extraction, including pH, extraction temperature, time, ionic strength, dosage of extraction agent and complexing agent were investigated and optimized.Under the optimum conditions, a good linear relationship was observed for manganese (Ⅱ) in the range of 100~700 ng/mL with the detection limit of 5.74 ng/mL and the relative standard deviations of 1.68% (n = 11 ).The recoveries were in the range of 97.3% ~98.6%.The method was rapid, accurate, simple and suitable to apply in the determination of manganese (Ⅱ) in honey.%研究了以8-羟基喹啉为络合剂,非离子表面活性剂TritonX-100为萃取剂的浊点萃取-火焰原子吸收光谱法(CPE-FAAS)测定蜂蜜中痕量Mn(Ⅱ)的方法.研究了pH值,平衡时间,离子强度,萃取剂用量,以及络合剂用量和共存离子干扰等对萃取效果的影响.方法线性范围为100 ~ 700 ng/mL,检出限为5.74 ng/mL,相对标准偏差为1.68% (n=11),回收率为97.3% ~98.6%.

  6. The 216-bp marB gene of the marRAB operon in Escherichia coli encodes a periplasmic protein which reduces the transcription rate of marA.

    Science.gov (United States)

    Vinué, Laura; McMurry, Laura M; Levy, Stuart B

    2013-08-01

    The marRAB operon is conserved in seven genera of enteric bacteria (Escherichia, Shigella, Klebsiella, Enterobacter, Salmonella, Cronobacter, and Citrobacter). MarA is a transcriptional regulator affecting many genes involved in resistance to stresses, and MarR is an autorepressor of the operon, but a role for the marB gene has been unclear. A recent work reported that deletion of marB causes resistance to certain stresses and increases the amount of marA transcript. We show here that the small (216 bp) marB gene encodes a protein, not an sRNA, because two different stop codons within the predicted open reading frame of marB prevented plasmid-borne marB from complementing ΔmarB::Kan. The ΔmarB::Kan mutation did not increase the stability of the marA transcript, suggesting that MarB does not destabilize the marA transcript but rather reduces its rate of transcription. Placing the putative signal sequence of MarB upstream of signal-sequence-less alkaline phosphatase guided the phosphatase to its normal periplasmic location. We conclude that MarB is a small periplasmic protein that represses the marRAB promoter by an indirect mechanism, possibly involving a signal to one of the cytoplasmic regulators of that promoter.

  7. The fire blight pathogen Erwinia amylovora requires the rpoN gene for pathogenicity in apple.

    Science.gov (United States)

    Ramos, Laura S; Lehman, Brian L; Sinn, Judith P; Pfeufer, Emily E; Halbrendt, Noemi O; McNellis, Timothy W

    2013-10-01

    RpoN is a σ(54) factor regulating essential virulence gene expression in several plant pathogenic bacteria, including Pseudomonas syringae and Pectobacterium carotovorum. In this study, we found that mutation of rpoN in the fire blight pathogen Erwinia amylovora caused a nonpathogenic phenotype. The E. amylovora rpoN Tn5 transposon mutant rpoN1250::Tn5 did not cause fire blight disease symptoms on shoots of mature apple trees. In detached immature apple fruits, the rpoN1250::Tn5 mutant failed to cause fire blight disease symptoms and grew to population levels 12 orders of magnitude lower than the wild-type. In addition, the rpoN1250::Tn5 mutant failed to elicit a hypersensitive response when infiltrated into nonhost tobacco plant leaves, and rpoN1250::Tn5 cells failed to express HrpN protein when grown in hrp (hypersensitive response and pathogenicity)-inducing liquid medium. A plasmid-borne copy of the wild-type rpoN gene complemented all the rpoN1250::Tn5 mutant phenotypes tested. The rpoN1250::Tn5 mutant was prototrophic on minimal solid and liquid media, indicating that the rpoN1250::Tn5 nonpathogenic phenotype was not caused by a defect in basic metabolism or growth. This study provides clear genetic evidence that rpoN is an essential virulence gene of E. amylovora, suggesting that rpoN has the same function in E. amylovora as in P. syringae and Pe. carotovorum.

  8. Mutation of the Erwinia amylovora argD gene causes arginine auxotrophy, nonpathogenicity in apples, and reduced virulence in pears.

    Science.gov (United States)

    Ramos, Laura S; Lehman, Brian L; Peter, Kari A; McNellis, Timothy W

    2014-11-01

    Fire blight is caused by Erwinia amylovora and is the most destructive bacterial disease of apples and pears worldwide. In this study, we found that E. amylovora argD(1000)::Tn5, an argD Tn5 transposon mutant that has the Tn5 transposon inserted after nucleotide 999 in the argD gene-coding region, was an arginine auxotroph that did not cause fire blight in apple and had reduced virulence in immature pear fruits. The E. amylovora argD gene encodes a predicted N-acetylornithine aminotransferase enzyme, which is involved in the production of the amino acid arginine. A plasmid-borne copy of the wild-type argD gene complemented both the nonpathogenic and the arginine auxotrophic phenotypes of the argD(1000)::Tn5 mutant. However, even when mixed with virulent E. amylovora cells and inoculated onto immature apple fruit, the argD(1000)::Tn5 mutant still failed to grow, while the virulent strain grew and caused disease. Furthermore, the pCR2.1-argD complementation plasmid was stably maintained in the argD(1000)::Tn5 mutant growing in host tissues without any antibiotic selection. Therefore, the pCR2.1-argD complementation plasmid could be useful for the expression of genes, markers, and reporters in E. amylovora growing in planta, without concern about losing the plasmid over time. The ArgD protein cannot be considered an E. amylovora virulence factor because the argD(1000)::Tn5 mutant was auxotrophic and had a primary metabolism defect. Nevertheless, these results are informative about the parasitic nature of the fire blight disease interaction, since they indicate that E. amylovora cannot obtain sufficient arginine from apple and pear fruit tissues or from apple vegetative tissues, either at the beginning of the infection process or after the infection has progressed to an advanced state.

  9. Prevalence of enteroaggregative Escherichia coli and its virulence-related genes in a case-control study among children from north-eastern Brazil.

    Science.gov (United States)

    Lima, Ila Fernanda Nunes; Boisen, Nadia; Quetz, Josiane da Silva; Havt, Alexandre; de Carvalho, Eunice Bobo; Soares, Alberto Melo; Lima, Noélia Leal; Mota, Rosa Maria Salani; Nataro, James P; Guerrant, Richard Littleton; Lima, Aldo Ângelo Moreira

    2013-05-01

    Enteroaggregative Escherichia coli (EAEC) is an important agent that causes endemic and epidemic diarrhoeal diseases worldwide. Several EAEC virulence-related genes (VRGs) have been described but their role in the clinical outcome of infection is not completely defined. This study investigated the prevalence of EAEC and potential associations of its VRGs with risk of or protection from diarrhoeal diseases in children from urban communities in north-eastern Brazil. The case-control study included 166 children, who had their stools evaluated for the EAEC diagnostic genes (aaiC and aatA) using PCR. Positive samples were further analysed by multiplex PCR and identified 18 VRGs. EAEC was found in the same proportion in both groups (41%). The plasmid-borne gene encoding a hexosyltransferase homologue (capU) was the most frequently detected (89.6%), followed by dispersin protein (aap, 58.2%) and EAEC HilA homologue (eilA, 57.8%). The AAF/III fimbrial subunit (agg3A) gene was observed at lower frequency (1.5%). Plasmid-encoded toxin (pet) or AAF/II fimbrial subunit (aafA) was associated significantly with disease. AAF/IV fimbrial subunit (agg4A) or hypothetical plasmid-encoded haemolysin (orf61) was detected significantly more in controls than in children with diarrhoea. In addition, one set of genes in combination, aaiC and agg3/4C but lacking agg4A and orf61, was associated with diarrhoea cases; and another one, orf61 in the absence of pet and aafA, was correlated with control children. These data confirm a high prevalence, endemicity and heterogeneity of EAEC strains in the developing urban areas of north-eastern Brazil. Statistical correlation between cases and controls was seen with either isolated or combined sets of genes, suggesting that the pathophysiology of EAEC infection involves a complex and dynamic modulation of several VRGs.

  10. Prevalence of enteroaggregative Escherichia coli and its virulence-related genes in a case–control study among children from north-eastern Brazil

    Science.gov (United States)

    Boisen, Nadia; Quetz, Josiane da Silva; Havt, Alexandre; de Carvalho, Eunice Bobo; Soares, Alberto Melo; Mota, Rosa Maria Salani; Nataro, James P.; Guerrant, Richard Littleton

    2013-01-01

    Enteroaggregative Escherichia coli (EAEC) is an important agent that causes endemic and epidemic diarrhoeal diseases worldwide. Several EAEC virulence-related genes (VRGs) have been described but their role in the clinical outcome of infection is not completely defined. This study investigated the prevalence of EAEC and potential associations of its VRGs with risk of or protection from diarrhoeal diseases in children from urban communities in north-eastern Brazil. The case–control study included 166 children, who had their stools evaluated for the EAEC diagnostic genes (aaiC and aatA) using PCR. Positive samples were further analysed by multiplex PCR and identified 18 VRGs. EAEC was found in the same proportion in both groups (41 %). The plasmid-borne gene encoding a hexosyltransferase homologue (capU) was the most frequently detected (89.6 %), followed by dispersin protein (aap, 58.2 %) and EAEC HilA homologue (eilA, 57.8 %). The AAF/III fimbrial subunit (agg3A) gene was observed at lower frequency (1.5 %). Plasmid-encoded toxin (pet) or AAF/II fimbrial subunit (aafA) was associated significantly with disease. AAF/IV fimbrial subunit (agg4A) or hypothetical plasmid-encoded haemolysin (orf61) was detected significantly more in controls than in children with diarrhoea. In addition, one set of genes in combination, aaiC and agg3/4C but lacking agg4A and orf61, was associated with diarrhoea cases; and another one, orf61 in the absence of pet and aafA, was correlated with control children. These data confirm a high prevalence, endemicity and heterogeneity of EAEC strains in the developing urban areas of north-eastern Brazil. Statistical correlation between cases and controls was seen with either isolated or combined sets of genes, suggesting that the pathophysiology of EAEC infection involves a complex and dynamic modulation of several VRGs. PMID:23429698

  11. PCR amplfication on a microarray of gel-immobilized oligonucleotides : detection of bacterial toxin- and drug-resistent genes and their mutations.

    Energy Technology Data Exchange (ETDEWEB)

    Strizhkov, B. N.; Drobyshev, A. L.; Mikhailovich, V. M.; Mirzabekov, A. D.; Biochip Technology Center; Engelhardt Inst. of Molecular Biology

    2000-10-01

    PCR amplification on a microarray of gel-immobilized primers (microchip) has been developed. One of a pair of PCR primers was immobilized inside a separate microchip polyacrylamide porous gel pad of 0.1 x 0.1 x 0.02 (or 0.04) micron in size and 0.2 (or 0.4) nL in volume. The amplification was carried out simultaneously both in solution covering the microchip array and inside gel pads. Each gel pad contained the immobilized forward primers, while the fluorescently labeled reverse primers, as well as all components of the amplification reaction, diffused into the gel pads from the solution. To increase the amplification efficiency, the forward primers were also added into the solution. The kinetics of amplification was measured in real time in parallel for all gel pads with a fluorescent microscope equipped with a charge-coupled device (CCD) camera. The accuracy of the amplification was assessed by using the melting curves obtained for the duplexes formed by the labeled amplification product and the gel-immobilized primers during the amplification process; alternatively, the duplexes were produced by hybridization of the extended immobilized primers with labeled oligonucleotide probes. The on-chip amplification was applied to detect the anthrax toxin genes and the plasmid-borne beta-lactamase gene responsible for bacterial ampicillin resistance. The allele-specific type of PCR amplification was used to identify the Shiga toxin gene and discriminate it from the Shiga-like one. The genomic mutations responsible for rifampicin resistance of the Mycobacterium tuberculosis strains were detected by the same type of PCR amplification of the rpoB gene fragment isolated from sputum of tuberculosis patients. The on-chip PCR amplification has been shown to be a rapid, inexpensive and powerful tool to test genes responsible for bacterial toxin production and drug resistance, as well as to reveal point nucleotide mutations.

  12. Effects of In-Feed Copper, Chlortetracycline, and Tylosin on the Prevalence of Transferable Copper Resistance Gene, tcrB, Among Fecal Enterococci of Weaned Piglets.

    Science.gov (United States)

    Amachawadi, Raghavendra G; Scott, H Morgan; Vinasco, Javier; Tokach, Mike D; Dritz, Steve S; Nelssen, Jim L; Nagaraja, Tiruvoor G

    2015-08-01

    Heavy metals, such as copper, are increasingly supplemented in swine diets as an alternative to antibiotics to promote growth. Enterococci, a common gut commensal, acquire plasmid-borne, transferable copper resistance (tcrB) gene-mediated resistance to copper. The plasmid also carried resistance genes to tetracyclines and macrolides. The potential genetic link between copper and antibiotic resistance suggests that copper supplementation may exert a selection pressure for antimicrobial resistance. Therefore, a longitudinal study was conducted to investigate the effects of in-feed copper, chlortetracycline, and tylosin alone or in combination on the selection and co-selection of antimicrobial-resistant enterococci. The study included 240 weaned piglets assigned randomly to 6 dietary treatment groups: control, copper, chlortetracycline, tylosin, copper and chlortetracycline, and copper and tylosin. Feces were collected before (day 0), during (days 7, 14, 21), and after (days 28 and 35) initiating treatment, and enterococcal isolates were obtained from each fecal sample and tested for genotypic and phenotypic resistance to copper and antibiotics. A total of 2592 enterococcal isolates were tested for tcrB by polymerase chain reaction. The overall prevalence of tcrB-positive enterococci was 14.3% (372/2592). Among the tcrB-positive isolates, 331 were Enterococcus faecium and 41 were E. faecalis. All tcrB-positive isolates contained both erm(B) and tet(M) genes. The median minimum inhibitory concentration of copper for tcrB-negative and tcrB-positive enterococci was 6 and 18 mM, respectively. The majority of isolates (95/100) were resistant to multiple antibiotics. In conclusion, supplementing copper or antibiotics alone did not increase copper-resistant enterococci; however, supplementing antibiotics with copper increased the prevalence of the tcrB gene among fecal enterococci of piglets.

  13. Identification and nitrogen regulation of the cyanase gene from the cyanobacteria Synechocystis sp. strain PCC 6803 and Synechococcus sp. strain PCC 7942.

    Science.gov (United States)

    Harano, Y; Suzuki, I; Maeda, S; Kaneko, T; Tabata, S; Omata, T

    1997-09-01

    An open reading frame (slr0899) on the genome of Synechocystis sp. strain PCC 6803 encodes a polypeptide of 149 amino acid residues, the sequence of which is 40% identical to that of cyanase from Escherichia coli. Introduction into a cyanase-deficient E. coli strain of a plasmid-borne slr0899 resulted in expression of low but significant activity of cyanase. Targeted interruption of a homolog of slr0899 from Synechococcus sp. strain PCC 7942, encoding a protein 77% identical to that encoded by slr0899, resulted in loss of cellular cyanase activity. These results indicated that slr0899 and its homolog in the strain PCC 7942 represent the cyanobacterial cyanase gene (designated cynS). While cynS of strain PCC 6803 is tightly clustered with the four putative molybdenum cofactor biosynthesis genes located downstream, cynS of strain PCC 7942 was found to be tightly clustered with the two genes located upstream, which encode proteins similar to the subunits of the cyanobacterial nitrate-nitrite transporter. In both strains, cynS was transcribed as a part of a large transcription unit and the transcription was negatively regulated by ammonium. Cyanase activity was low in ammonium-grown cells and was induced 7- to 13-fold by inhibition of ammonium fixation or by transfer of the cells to ammonium-free media. These findings indicated that cyanase is an ammonium-repressible enzyme in cyanobacteria, the expression of which is regulated at the level of transcription. Similar to other ammonium-repressible genes in cyanobacteria, expression of cynS required NtcA, a global nitrogen regulator of cyanobacteria.

  14. Sequencing of IncX-plasmids suggests ubiquity of mobile forms of a biofilm-promoting gene cassette recruited from Klebsiella pneumoniae.

    Directory of Open Access Journals (Sweden)

    Mette Burmølle

    Full Text Available Plasmids are a highly effective means with which genetic traits that influence human health, such as virulence and antibiotic resistance, are disseminated through bacterial populations. The IncX-family is a hitherto sparsely populated group of plasmids that are able to thrive within Enterobacteriaceae. In this study, a replicon-centric screening method was used to locate strains from wastewater sludge containing plasmids belonging to the IncX-family. A transposon aided plasmid capture method was then employed to transport IncX-plasmids from their original hosts (and co-hosted plasmids into a laboratory strain (Escherichia coli Genehogs® for further study. The nucleotide sequences of the three newly isolated IncX-plasmids (pLN126_33, pMO17_54, pMO440_54 and the hitherto un-sequenced type-plasmid R485 revealed a remarkable occurrence of whole or partial gene cassettes that promote biofilm-formation in Klebsiella pneumonia or E. coli, in all four instances. Two of the plasmids (R485 and pLN126_33 were shown to directly induce biofilm formation in a crystal violet retention assay in E. coli. Sequence comparison revealed that all plasmid-borne forms of the type 3 fimbriae encoding gene cassette mrkABCDF were variations of a composite transposon Tn6011 first described in the E. coli IncX plasmid pOLA52. In conclusion, IncX-plasmids isolated from Enterobacteriaceae over almost 40 years and on three different continents have all been shown to carry a type 3 fimbriae gene cassette mrkABCDF stemming from pathogenic K. pneumoniae. Apart from contributing general knowledge about IncX-plasmids, this study also suggests an apparent ubiquity of a mobile form of an important virulence factor and is an illuminating example of the recruitment, evolution and dissemination of genetic traits through plasmid-mediated horizontal gene transfer.

  15. Sequencing of IncX-plasmids suggests ubiquity of mobile forms of a biofilm-promoting gene cassette recruited from Klebsiella pneumoniae.

    Science.gov (United States)

    Burmølle, Mette; Norman, Anders; Sørensen, Søren J; Hansen, Lars Hestbjerg

    2012-01-01

    Plasmids are a highly effective means with which genetic traits that influence human health, such as virulence and antibiotic resistance, are disseminated through bacterial populations. The IncX-family is a hitherto sparsely populated group of plasmids that are able to thrive within Enterobacteriaceae. In this study, a replicon-centric screening method was used to locate strains from wastewater sludge containing plasmids belonging to the IncX-family. A transposon aided plasmid capture method was then employed to transport IncX-plasmids from their original hosts (and co-hosted plasmids) into a laboratory strain (Escherichia coli Genehogs®) for further study. The nucleotide sequences of the three newly isolated IncX-plasmids (pLN126_33, pMO17_54, pMO440_54) and the hitherto un-sequenced type-plasmid R485 revealed a remarkable occurrence of whole or partial gene cassettes that promote biofilm-formation in Klebsiella pneumonia or E. coli, in all four instances. Two of the plasmids (R485 and pLN126_33) were shown to directly induce biofilm formation in a crystal violet retention assay in E. coli. Sequence comparison revealed that all plasmid-borne forms of the type 3 fimbriae encoding gene cassette mrkABCDF were variations of a composite transposon Tn6011 first described in the E. coli IncX plasmid pOLA52. In conclusion, IncX-plasmids isolated from Enterobacteriaceae over almost 40 years and on three different continents have all been shown to carry a type 3 fimbriae gene cassette mrkABCDF stemming from pathogenic K. pneumoniae. Apart from contributing general knowledge about IncX-plasmids, this study also suggests an apparent ubiquity of a mobile form of an important virulence factor and is an illuminating example of the recruitment, evolution and dissemination of genetic traits through plasmid-mediated horizontal gene transfer.

  16. Na(+) dependent acid-base transporters in the choroid plexus; insights from slc4 and slc9 gene deletion studies.

    Science.gov (United States)

    Christensen, Henriette L; Nguyen, An T; Pedersen, Fredrik D; Damkier, Helle H

    2013-10-22

    The choroid plexus epithelium (CPE) is located in the ventricular system of the brain, where it secretes the majority of the cerebrospinal fluid (CSF) that fills the ventricular system and surrounds the central nervous system. The CPE is a highly vascularized single layer of cuboidal cells with an unsurpassed transepithelial water and solute transport rate. Several members of the slc4a family of bicarbonate transporters are expressed in the CPE. In the basolateral membrane the electroneutral Na(+) dependent Cl(-)/HCO3 (-) exchanger, NCBE (slc4a10) is expressed. In the luminal membrane, the electrogenic Na(+):HCO3 (-) cotransporter, NBCe2 (slc4a5) is expressed. The electroneutral Na(+):HCO3 (-) cotransporter, NBCn1 (slc4a7), has been located in both membranes. In addition to the bicarbonate transporters, the Na(+)/H(+) exchanger, NHE1 (slc9a1), is located in the luminal membrane of the CPE. Genetically modified mice targeting slc4a2, slc4a5, slc4a7, slc4a10, and slc9a1 have been generated. Deletion of slc4a5, 7 or 10, or slc9a1 has numerous impacts on CP function and structure in these mice. Removal of the transporters affects brain ventricle size (slc4a5 and slc4a10) and intracellular pH regulation (slc4a7 and slc4a10). In some instances, removal of the proteins from the CPE (slc4a5, 7, and 10) causes changes in abundance and localization of non-target transporters known to be involved in pH regulation and CSF secretion. The focus of this review is to combine the insights gathered from these knockout mice to highlight the impact of slc4 gene deletion on the CSF production and intracellular pH regulation resulting from the deletion of slc4a5, 7 and 10, and slc9a1. Furthermore, the review contains a comparison of the described human mutations of these genes to the findings in the knockout studies. Finally, the future perspective of utilizing these proteins as potential targets for the treatment of CSF disorders will be discussed.

  17. Multiplex real-time PCR assay for detection and classification of Klebsiella pneumoniae carbapenemase gene (bla KPC) variants.

    Science.gov (United States)

    Chen, Liang; Mediavilla, José R; Endimiani, Andrea; Rosenthal, Marnie E; Zhao, Yanan; Bonomo, Robert A; Kreiswirth, Barry N

    2011-02-01

    Carbapenem resistance mediated by plasmid-borne Klebsiella pneumoniae carbapenemases (KPC) is an emerging problem of significant clinical importance in Gram-negative bacteria. Multiple KPC gene variants (bla(KPC)) have been reported, with KPC-2 (bla(KPC-2)) and KPC-3 (bla(KPC-3)) associated with epidemic outbreaks in New York City and various international settings. Here, we describe the development of a multiplex real-time PCR assay using molecular beacons (MB-PCR) for rapid and accurate identification of bla(KPC) variants. The assay consists of six molecular beacons and two oligonucleotide primer pairs, allowing for detection and classification of all currently described bla(KPC) variants (bla(KPC-2) to bla(KPC-11)). The MB-PCR detection limit was 5 to 40 DNA copies per reaction and 4 CFU per reaction using laboratory-prepared samples. The MB-PCR probes were highly specific for each bla(KPC) variant, and cross-reactivity was not observed using DNA isolated from several bacterial species. A total of 457 clinical Gram-negative isolates were successfully characterized by our MB-PCR assay, with bla(KPC-3) and bla(KPC-2) identified as the most common types in the New York/New Jersey metropolitan region. The MB-PCR assay described herein is rapid, sensitive, and specific and should be useful for understanding the ongoing evolution of carbapenem resistance in Gram-negative bacteria. As novel bla(KPC) variants continue to emerge, the MB-PCR assay can be modified in response to epidemiologic developments.

  18. The 380 kb pCMU01 plasmid encodes chloromethane utilization genes and redundant genes for vitamin B12- and tetrahydrofolate-dependent chloromethane metabolism in Methylobacterium extorquens CM4: a proteomic and bioinformatics study.

    Directory of Open Access Journals (Sweden)

    Sandro Roselli

    Full Text Available Chloromethane (CH3Cl is the most abundant volatile halocarbon in the atmosphere and contributes to the destruction of stratospheric ozone. The only known pathway for bacterial chloromethane utilization (cmu was characterized in Methylobacterium extorquens CM4, a methylotrophic bacterium able to utilize compounds without carbon-carbon bonds such as methanol and chloromethane as the sole carbon source for growth. Previous work demonstrated that tetrahydrofolate and vitamin B12 are essential cofactors of cmuA- and cmuB-encoded methyltransferases of chloromethane dehalogenase, and that the pathway for chloromethane utilization is distinct from that for methanol. This work reports genomic and proteomic data demonstrating that cognate cmu genes are located on the 380 kb pCMU01 plasmid, which drives the previously defined pathway for tetrahydrofolate-mediated chloromethane dehalogenation. Comparison of complete genome sequences of strain CM4 and that of four other M. extorquens strains unable to grow with chloromethane showed that plasmid pCMU01 harbors unique genes without homologs in the compared genomes (bluB2, btuB, cobA, cbiD, as well as 13 duplicated genes with homologs of chromosome-borne genes involved in vitamin B12-associated biosynthesis and transport, or in tetrahydrofolate-dependent metabolism (folC2. In addition, the presence of both chromosomal and plasmid-borne genes for corrinoid salvaging pathways may ensure corrinoid coenzyme supply in challenging environments. Proteomes of M. extorquens CM4 grown with one-carbon substrates chloromethane and methanol were compared. Of the 49 proteins with differential abundance identified, only five (CmuA, CmuB, PurU, CobH2 and a PaaE-like uncharacterized putative oxidoreductase are encoded by the pCMU01 plasmid. The mainly chromosome-encoded response to chloromethane involves gene clusters associated with oxidative stress, production of reducing equivalents (PntAA, Nuo complex, conversion of

  19. Heterooligomeric phosphoribosyl diphosphate synthase of Saccharomyces cerevisiae: combinatorial expression of the five PRS genes in Escherichia coli.

    Science.gov (United States)

    Hove-Jensen, Bjarne

    2004-09-24

    The yeast Saccharomyces cerevisiae contains five phosphoribosyl diphosphate (PRPP) synthase-homologous genes (PRS1-5), which specify PRPP synthase subunits 1-5. Expression of the five S. cerevisiae PRS genes individually in an Escherichia coli PRPP-less strain (Deltaprs) showed that a single PRS gene product had no PRPP synthase activity. In contrast, expression of five pairwise combinations of PRS genes resulted in the formation of active PRPP synthase. These combinations were PRS1 PRS2, PRS1 PRS3, and PRS1 PRS4, as well as PRS5 PRS2 and PRS5 PRS4. None of the remaining five possible pairwise combinations of PRS genes appeared to produce active enzyme. Extract of an E. coli strain containing a plasmid-borne PRS1 gene and a chromosome-borne PRS3 gene contained detectable PRPP synthase activity, whereas extracts of strains containing PRS1 PRS2, PRS1 PRS4, PRS5 PRS2, or PRS5 PRS4 contained no detectable PRPP synthase activity. In contrast PRPP could be detected in growing cells containing PRS1 PRS2, PRS1 PRS3, PRS5 PRS2, or PRS5 PRS4. These apparent conflicting results indicate that, apart from the PRS1 PRS3-specified enzyme, PRS-specified enzyme is functional in vivo but unstable when released from the cell. Certain combinations of three PRS genes appeared to produce an enzyme that is stable in vitro. Thus, extracts of strains harboring PRS1 PRS2 PRS5, PRS1 PRS4 PRS5, or PRS2 PRS4 PRS5 as well as extracts of strains harboring combinations with PRS1 PRS3 contained readily assayable PRPP synthase activity. The data indicate that although certain pairwise combinations of subunits produce an active enzyme, yeast PRPP synthase requires at least three different subunits to be stable in vitro. The activity of PRPP synthases containing subunits 1 and 3 or subunits 1, 2, and 5 was found to be dependent on Pi, to be temperature-sensitive, and inhibited by ADP.

  20. Identification of ABC transporter genes conferring combined pleuromutilin-lincosamide-streptogramin A resistance in bovine methicillin-resistant Staphylococcus aureus and coagulase-negative staphylococci.

    Science.gov (United States)

    Wendlandt, Sarah; Kadlec, Kristina; Feßler, Andrea T; Schwarz, Stefan

    2015-06-12

    The aim of this study was to investigate the genetic basis of combined pleuromutilin-lincosamide-streptogramin A resistance in 26 unrelated methicillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative staphylococci (CoNS) from dairy cows suffering from mastitis. The 26 pleuromutilin-resistant staphylococcal isolates were screened for the presence of the genes vga(A), vga(B), vga(C), vga(E), vga(E) variant, sal(A), vmlR, cfr, lsa(A), lsa(B), lsa(C), and lsa(E) by PCR. None of the 26 isolates carried the genes vga(B), vga(C), vga(E), vga(E) variant, vmlR, cfr, lsa(A), lsa(B), or lsa(C). Two Staphylococcus haemolyticus and single Staphylococcus xylosus, Staphylococcus lentus, and Staphylococcus hominis were vga(A)-positive. Twelve S. aureus, two Staphylococcus warneri, as well as single S. lentus and S. xylosus carried the lsa(E) gene. Moreover, single S. aureus, S. haemolyticus, S. xylosus, and Staphylococcus epidermidis were positive for both genes, vga(A) and lsa(E). The sal(A) gene was found in a single Staphylococcus sciuri. All ABC transporter genes were located in the chromosomal DNA, except for a plasmid-borne vga(A) gene in the S. epidermidis isolate. The genetic environment of the lsa(E)-positive isolates was analyzed using previously described PCR assays. Except for the S. warneri and S. xylosus, all lsa(E)-positive isolates harbored a part of the previously described enterococcal multiresistance gene cluster. This is the first report of the novel lsa(E) gene in the aforementioned bovine CoNS species. This is also the first identification of the sal(A) gene in a S. sciuri from a case of bovine mastitis. Moreover, the sal(A) gene was shown to also confer pleuromutilin resistance. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Whole genome sequencing and analysis of Campylobacter coli YH502 from retail chicken reveals a plasmid-borne type VI secretion system

    Science.gov (United States)

    Campylobacter is a major cause of foodborne illnesses worldwide. Campylobacter infections, commonly caused by ingestion of undercooked poultry and meat products, can lead to gastroenteritis and chronic reactive arthritis in humans. Whole genome sequencing (WGS) is a powerful technology that provides...

  2. Genetic Association Analysis of 30 Genes Related to Obesity in a European American Population

    Science.gov (United States)

    Li, Peng; Tiwari, Hemant K.; Lin, Wan-Yu; Allison, David B.; Chung, Wendy K.; Leibel, Rudolph L.; Yi, Nengjun; Liu, Nianjun

    2013-01-01

    Objective Obesity, which is frequently associated with diabetes, hypertension, and cardiovascular diseases, is primarily the result of a net excess of caloric intake over energy expenditure. Human obesity is highly heritable, but the specific genes mediating susceptibility in non-syndromic obesity remain unclear. We tested candidate genes in pathways related to food intake and energy expenditure for association with body mass index (BMI). Methods We re-analyzed 355 common genetic variants of 30 candidate genes in 7 molecular pathways related to obesity in 1,982 unrelated European Americans from the New York Health Project. Data were analyzed by using a Bayesian hierarchical generalized linear model. The BMIs were log-transformed and then adjusted for covariates including age, age2, gender, and diabetes status. The single nucleotide polymorphisms (SNPs) were modeled as additive effects. Results With the stipulated adjustments, nine SNPs in eight genes were significantly associated with BMI: GHRL (rs35683), AGRP (rs5030980), CPE (rs1946816 and rs4481204), GLP1R (rs2268641), HTR2A (rs912127), NPY5R (Y5R1c52), SOCS3 (rs4969170), and STAT3 (rs4796793). We also found a gender-by-SNP interaction (rs1745837 in HTR2A), which indicated that variants in the gene HTR2A had a stronger association with BMI in males. In addition, NPY1R was detected as having a significant gene effect even though none of the SNPs in this gene was significant. Conclusion Variations in genes AGRP, CPE, GHRL, GLP1R, HTR2A, NPY1R, NPY5R, SOCS3, and STAT3 showed modest associations with BMI in European Americans. The pathways in which these genes participate regulate energy intake and thus these associations are mechanistically plausible in this context. PMID:23900445

  3. Genetic association analysis of 30 genes related to obesity in a European American population.

    Science.gov (United States)

    Li, P; Tiwari, H K; Lin, W-Y; Allison, D B; Chung, W K; Leibel, R L; Yi, N; Liu, N

    2014-05-01

    Obesity, which is frequently associated with diabetes, hypertension and cardiovascular diseases, is primarily the result of a net excess of caloric intake over energy expenditure. Human obesity is highly heritable, but the specific genes mediating susceptibility in non-syndromic obesity remain unclear. We tested candidate genes in pathways related to food intake and energy expenditure for association with body mass index (BMI). We reanalyzed 355 common genetic variants of 30 candidate genes in seven molecular pathways related to obesity in 1982 unrelated European Americans from the New York Cancer Project. Data were analyzed by using a Bayesian hierarchical generalized linear model. The BMIs were log-transformed and then adjusted for covariates, including age, age(2), gender and diabetes status. The single-nucleotide polymorphisms (SNPs) were modeled as additive effects. With the stipulated adjustments, nine SNPs in eight genes were significantly associated with BMI: ghrelin (GHRL; rs35683), agouti-related peptide (AGRP; rs5030980), carboxypeptidase E (CPE; rs1946816 and rs4481204), glucagon-like peptide-1 receptor (GLP1R; rs2268641), serotonin receptors (HTR2A; rs912127), neuropeptide Y receptor (NPY5R;Y5R1c52), suppressor of cytokine signaling 3 (SOCS3; rs4969170) and signal transducer and activator of transcription 3 (STAT3; rs4796793). We also found a gender-by-SNP interaction (rs1745837 in HTR2A), which indicated that variants in the gene HTR2A had a stronger association with BMI in males. In addition, NPY1R was detected as having a significant gene effect even though none of the SNPs in this gene was significant. Variations in genes AGRP, CPE, GHRL, GLP1R, HTR2A, NPY1R, NPY5R, SOCS3 and STAT3 showed modest associations with BMI in European Americans. The pathways in which these genes participate regulate energy intake, and thus these associations are mechanistically plausible in this context.

  4. Caracterización molecular y resistencia antimicrobiana de aislamientos de Clostridium perfringens de diferentes orígenes en Costa Rica

    Directory of Open Access Journals (Sweden)

    María del Mar Gamboa-Coronado

    2011-12-01

    Full Text Available Clostridium perfringens es un bacilo Gram positivo, esporulado, anaerobio, ampliamente distribuido en la naturaleza, que produce cuatro toxinas principales α, β, ε y ι, las cuales permiten su clasificación en cinco toxinotipos (A-E. Algunas cepas producen una enterotoxina (CPE, codificada por el gen cpe, que causa diarrea en seres humanos y en algunos animales. La presencia de los genes de estas toxinas y la sensibilidad a los antibióticos se determinó en 81 cepas de C. perfringens previamente aisladas y que habían sido mantenidas a -80°C; 20 de suelos, 20 de origen animal, 20 de origen humano y 21 de alimentos cocidos no relacionados con brotes alimentarios. De acuerdo con los resultados de PCR, todas las cepas fueron clasificadas como C. perfringens tipo A, debido a que solo se les detectó el gen de la toxina α, mientras que el gen de la enterotoxina (cpe se detectó en dos cepas (2.5% aisladas de alimentos, tal como ha sido descrito en otras regiones del mundo. El 44% de las cepas fue resistente a algún antibiótico; clindamicina (41%, cloranfenicol (25%, penicilina (22% y metronidazol (20%. En general, las cepas provenientes de suelos presentaron los mayores porcentajes de resistencia a casi todos los antibióticos. El 40% de las cepas de suelo presentó multiresistencia (a tres o más grupos de antibióticos, el 30% de las de origen humano, el 14% de las de alimentos y el 5% de las de origen animal. Las altas tasas de resistencia encontradas podrían deberse al amplio uso de antibióticos como promotores de crecimiento de plantas y animales y esas cepas resistentes podrían actuar como reservorio de genes de resistencia que pueden transferirse entre bacterias de diversos ambientes.Molecular characterization and antimicrobial resistance of Clostridium perfringens isolates of different origins from Costa Rica. Clostridium perfringens, a Gram positive, spore-forming anaerobe, is widely distributed in nature. Based upon their

  5. Genes and Gene Therapy

    Science.gov (United States)

    ... correctly, a child can have a genetic disorder. Gene therapy is an experimental technique that uses genes to ... or prevent disease. The most common form of gene therapy involves inserting a normal gene to replace an ...

  6. Cytopathic Effect (CPE) and Adaption of HFRS Virus Vaccine Strain E37 in Green Mondey kidney Cell%HFRS病毒Z37株在绿猴肾传代细胞的病变作用和传代适应

    Institute of Scientific and Technical Information of China (English)

    李敏红; 翁景清; 陆群英; 姚苹苹; 朱函坪; 朱智勇; 越芝雅; 傅桂明

    2001-01-01

    [目的]研究肾综合征出血热(HFRS)病毒Z37疫苗株在绿猴肾传代细胞(vero,vero-E6)上的病变和传代适应增殖情况,为应用vero细胞研制出血热疫苗提供科学依据.[方法]将肾综合征出血热疫苗株Z37适应在绿猴肾传代细胞(vero,vero-E6)上,对细胞进行细胞病变(CPE)的动态观察,并于不同的时间取样,测定病毒滴度,比较静置培养、转瓶培养滴度的差异情况.[结果]Z37株不使vero-E6细胞产生病变,用HEPES诱导,3d可见明显病变现象.Z37株不使vero细胞产生病变,用HEPES诱导病变现象未获成功,Z37株在vero细胞中可高滴度繁殖,滴度达到107/ml,转瓶培养病毒滴度略高于静置培养.[结论]应用vero细胞研制HFRS疫苗是可行的.

  7. A Multi-tracer Dopaminergic PET Study of Young-Onset Parkinsonian Patients With and Without Parkin Gene Mutations

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, M.J. [CEA, I2BM, Service Hospitalier Frederic Joliot, Orsay (France); Thobois, St.; Broussolle, E. [University of Lyon, Hospices Civils de Lyon, Neurological Hospital, Lyon (France); Lohmann, E.; Lesage, S.; Dubois, B.; Agid, Y.; Brice, A. [INSERM, Paris (France); Lohmann, E.; Agid, Y.; Brice, A. [Department of the Nervous System Disorders, AP-HP, Pitie-Salpetriere Hospital, Paris (France); Lohmann, E.; Lesage, S.; Dubois, B.; Agid, Y.; Brice, A. [UPMC University of Paris, Paris (France); Tezenas du Montcel, S. [Unit of de Biostatistics and Medical Information and Unit of Medical Research, AP-HP, Pitie-Salpetriere Hospital, Paris (France); Tezenas du Montcel, S. [Modelisation in Clinical Research, UPMC University of Paris, Paris (France); Pelissolo, A. [Department of Psychiatry, AP-HP, Pitie-Salpetriere Hospital, Paris (France); Dubois, B. [Centre de Reference sur la Maladie de Pick, AP-HP, Pitie-Salpetriere Hospital, Paris (France); Mallet, L. [Behaviour, Emotion and Basal Ganglia, Center of Clinical Investigation, INSERM Avenir Group, Paris (France); Pollak, P. [Department of Clinical and Biological Neurosciences, University Hospital of Grenoble, Grenoble (France); Agid, Y. [Clinical Investigation Center, AP-HP, Pitie-Salpetriere Hospital, Paris (France); Brice, A. [Department of Genetics and Cytogenetics, AP-HP, Pitie-Salpetriere Hospital, Paris (France); Remy, Ph. [CEA, I2BM, MIRCEN, URA CEA-CNRS 2210, Orsay (France); Remy, Ph. [CHU Henri Mondor, AP-HP and Faculte de Medecine Paris 12, Creteil (France)

    2009-07-01

    The impact of parkin gene mutations on nigrostriatal dopaminergic degeneration is not well established. The purpose of this study was to characterize by PET using {sup 18}F-fluoro-L-3, 4- dihydroxyphenylalanine ({sup 18}F-fluoro-L-DOPA), {sup 11}C-PE2I, and {sup 11}C-raclopride the pattern of dopaminergic lesions in young-onset Parkinson disease (YOPD) patients with or without mutations of the parkin gene and to correlate the clinical and neuro-psychologic characteristics of these patients with PET results. Methods: A total of 35 YOPD patients were enrolled (16 with parkin mutation, 19 without). The uptake constant (K{sub i}) of {sup 18}F-fluoro- L-DOPA and the binding potential (BP) of {sup 11}C-PE2I (BPDAT) and of {sup 11}C-raclopride (BPD2) were calculated in the striatum. Comparisons were made between the 2 groups of YOPD and between controls and patients. For each radiotracer, parametric images were obtained, and statistical parametric mapping (SPM) analysis using a voxel-by-voxel statistical t test was performed. Correlations between the cognitive and motor status and PET results were analyzed. Results: In YOPD patients, {sup 18}F-fluoro-L-DOPA K{sub i} values were reduced to 68% (caudate) and 40% (putamen) of normal values (P {<=} 0.0001). This decrease was symmetric and comparable for non-parkin and parkin patients. No correlation was found between the K{sub i} values and cognitive or motor status. {sup 11}C-PE2I BPDAT values in YOPD patients were decreased to 56% (caudate) and 41% (putamen) of normal values (P {<=} 0.0001) and did not differ between the 2 YOPD populations. The mean {sup 11}C-raclopride BPD2 values were reduced to 72% (caudate) and 84% (putamen) of the normal values (P {<=} 0.02) and did not differ between non-parkin and parkin patients. SPM analyses showed in patients an additional decrease of {sup 11}C-raclopride in the frontal cortex and a decrease of {sup 18}F-fluoro-L-DOPA and {sup 11}C-PE2I uptake in the substantia nigra bilaterally

  8. Comparison of toxicity neutralization-, ELISA- and PCR tests for typing of Clostridium perfringens and detection of the enterotoxin gene by PCR

    DEFF Research Database (Denmark)

    Møller, Kristian; Ahrens, Peter

    1996-01-01

    A polymerase chain reaction (PCR) was developed for the specific amplification of a part of each of the five Clostridium perfringens toxin genes: alpha (alpha), beta (beta), epsilon (epsilon), iota (iota), and enterotoxin (CPE). While the toxicity neutralization test (TNT) only showed limited...... ability to detect the or toxin, the lecithinase test and PCR test (PCR(alpha)) concordantly detected the ct toxin and the alpha toxin gene, respectively. A monoclonal enzyme linked immunosorbent assay (ELISA) and a PCR(beta) test were compared and were in accordance for the detection of the beta toxin...... (gene) from pure and mixed cultures from piglets suffering from necrotizing enteritis. However, the PCR(beta) test was superior to the ELISA for detection of the beta toxin (gene) in necrotic intestinal mucosa without culturing. An internal standard to be co-amplified with the beta toxin gene...

  9. Caracterización molecular y resistencia antimicrobiana de aislamientos de Clostridium perfringens de diferentes orígenes en Costa Rica

    Directory of Open Access Journals (Sweden)

    María del Mar Gamboa-Coronado

    2011-12-01

    Full Text Available Clostridium perfringens es un bacilo Gram positivo, esporulado, anaerobio, ampliamente distribuido en la naturaleza, que produce cuatro toxinas principales α, β, ε y ι, las cuales permiten su clasificación en cinco toxinotipos (A-E. Algunas cepas producen una enterotoxina (CPE, codificada por el gen cpe, que causa diarrea en seres humanos y en algunos animales. La presencia de los genes de estas toxinas y la sensibilidad a los antibióticos se determinó en 81 cepas de C. perfringens previamente aisladas y que habían sido mantenidas a -80°C; 20 de suelos, 20 de origen animal, 20 de origen humano y 21 de alimentos cocidos no relacionados con brotes alimentarios. De acuerdo con los resultados de PCR, todas las cepas fueron clasificadas como C. perfringens tipo A, debido a que solo se les detectó el gen de la toxina α, mientras que el gen de la enterotoxina (cpe se detectó en dos cepas (2.5% aisladas de alimentos, tal como ha sido descrito en otras regiones del mundo. El 44% de las cepas fue resistente a algún antibiótico; clindamicina (41%, cloranfenicol (25%, penicilina (22% y metronidazol (20%. En general, las cepas provenientes de suelos presentaron los mayores porcentajes de resistencia a casi todos los antibióticos. El 40% de las cepas de suelo presentó multiresistencia (a tres o más grupos de antibióticos, el 30% de las de origen humano, el 14% de las de alimentos y el 5% de las de origen animal. Las altas tasas de resistencia encontradas podrían deberse al amplio uso de antibióticos como promotores de crecimiento de plantas y animales y esas cepas resistentes podrían actuar como reservorio de genes de resistencia que pueden transferirse entre bacterias de diversos ambientes.

  10. Draft Genome of Multidrug-Resistant Klebsiella pneumoniae 223/14 Carrying KPC-6, Isolated from a General Hospital in Malaysia

    Science.gov (United States)

    Ahmad, Norazah; Chong, Teik Min; Hashim, Rohaidah; Shukor, Surianti; Yin, Wai-Fong; Chan, Kok-Gan

    2015-01-01

    We performed whole genome sequencing on a clinical multidrug-resistant Klebsiella pneumoniae strain 223/14. Investigation into its draft genome revealed the presence of KPC-6 variant, suggesting carbapenemase is present in this isolate. We found a plasmid-borne KPC gene (882 bp) inserted between two transposase genes in the genome of K. pneumoniae 223/14. PMID:26816553

  11. Comparison of in-house and commercial real time-PCR based carbapenemase gene detection methods in Enterobacteriaceae and non-fermenting gram-negative bacterial isolates.

    Science.gov (United States)

    Smiljanic, M; Kaase, M; Ahmad-Nejad, P; Ghebremedhin, B

    2017-07-10

    Carbapenemase-producing gram-negative bacteria are increasing globally and have been associated with outbreaks in hospital settings. Thus, the accurate detection of these bacteria in infections is mandatory for administering the adequate therapy and infection control measures. This study aimed to establish and evaluate a multiplex real-time PCR assay for the simultaneous detection of carbapenemase gene variants in gram-negative rods and to compare the performance with a commercial RT-PCR assay (Check-Direct CPE). 116 carbapenem-resistant Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter baumannii isolates were genotyped for carbapenemase genes by PCR and sequencing. The defined isolates were used for the validation of the in-house RT-PCR by use of designed primer pairs and probes. Among the carbapenem-resistant isolates the genes bla KPC, bla VIM, bla NDM or bla OXA were detected. Both RT-PCR assays detected all bla KPC, bla VIM and bla NDM in the isolates. The in-house RT-PCR detected 53 of 67 (79.0%) whereas the commercial assay detected only 29 (43.3%) of the OXA genes. The in-house sufficiently distinguished the most prevalent OXA types (23-like and 48-like) in the melting curve analysis and direct detection of the genes from positive blood culture vials. The Check-Direct CPE and the in-house RT-PCR assay detected the carbapenem resistance from solid culture isolates. Moreover, the in-house assay enabled the identification of carbapenemase genes directly from positive blood-culture vials. However, we observed insufficient detection of various OXA genes in both assays. Nevertheless, the in-house RT-PCR detected the majority of the OXA type genes in Enterobacteriaceae and A. baumannii.

  12. Detection of the pediocin gene pedA in strains from human faeces by real-time PCR and characterization of Pediococcus acidilactici UVA1

    Directory of Open Access Journals (Sweden)

    Cereghetti Tania

    2007-09-01

    Full Text Available Abstract Background Bacteriocin-producing lactic acid bacteria are commonly used as natural protective cultures. Among them, strains of the genus Pediococcus are particularly interesting for their ability to produce pediocin, a broad spectrum antimicrobial peptide with a strong antagonistic activity against the food-borne pathogen Listeria monocytogenes. Furthermore, there is increasing interest in isolating new bacteriocin-producing strains of human intestinal origin that could be developed for probiotic effects and inhibition of pathogenic bacteria in the gut. In this work, we typed a new strain, co-isolated from baby faeces together with a Bifidobacterium thermophilum strain, and characterized its proteinaceous compound with strong antilisterial activity. Results The newly isolated strain UVA1 was identified as a Pediococcus acidilactici by carbohydrate fermentation profile, growth at 50°C and 16S rDNA sequencing. The partially purified bacteriocin was heat resistant up to 100°C, active over a wide range of pH (2 to 9 and susceptible to proteolytic enzymes. The molecular weight, estimated by SDS-PAGE, was similar to that of pediocin AcH/PA-1 (4.5 kDa. P. acidilactici UVA1 harboured a 9.5-kb plasmid that could be cured easily, which resulted in the loss of the antimicrobial activity. Southern hybridization using the DIG-labelled pedA-probe established that the bacteriocin gene was plasmid-borne as for all pediocin described so far. Nucleotide sequence of the whole operon (3.5 kb showed almost 100 % similarity to the pediocin AcH/PA-1 operon. The mRNA transcript for pedA could be detected in P. acidilactici UVA1 but not in the cured derivative, confirming the expression of the pedA-gene in UVA1. Using a new real-time PCR assay, eleven out of seventeen human faecal samples tested were found to contain pedA-DNA. Conclusion We identified and characterised the first pediocin produced by a human intestinal Pediococcus acidilactici isolate and

  13. Novel plasmid conferring kanamycin and tetracycline resistance in turkey-derived Campylobacter jejuni strain 11601MD

    Science.gov (United States)

    In Campylobacter spp., resistance to the antibiotics kanamycin and tetracycline is frequently associated with plasmid-borne genes. However, relatively few plasmids of Campylobacter jejuni have been fully characterized to date. A novel plasmid (p11601MD; 44,095 bp.) harboring tet(O) was identified in...

  14. Approaching the axiomatic enrichment of the Gene Ontology from a lexical perspective.

    Science.gov (United States)

    Quesada-Martínez, Manuel; Mikroyannidi, Eleni; Fernández-Breis, Jesualdo Tomás; Stevens, Robert

    2015-09-01

    The main goal of this work is to measure how lexical regularities in biomedical ontology labels can be used for the automatic creation of formal relationships between classes, and to evaluate the results of applying our approach to the Gene Ontology (GO). In recent years, we have developed a method for the lexical analysis of regularities in biomedical ontology labels, and we showed that the labels can present a high degree of regularity. In this work, we extend our method with a cross-products extension (CPE) metric, which estimates the potential interest of a specific regularity for axiomatic enrichment in the lexical analysis, using information on exact matches in external ontologies. The GO consortium recently enriched the GO by using so-called cross-product extensions. Cross-products are generated by establishing axioms that relate a given GO class with classes from the GO or other biomedical ontologies. We apply our method to the GO and study how its lexical analysis can identify and reconstruct the cross-products that are defined by the GO consortium. The label of the classes of the GO are highly regular in lexical terms, and the exact matches with labels of external ontologies affect 80% of the GO classes. The CPE metric reveals that 31.48% of the classes that exhibit regularities have fragments that are classes into two external ontologies that are selected for our experiment, namely, the Cell Ontology and the Chemical Entities of Biological Interest ontology, and 18.90% of them are fully decomposable into smaller parts. Our results show that the CPE metric permits our method to detect GO cross-product extensions with a mean recall of 62% and a mean precision of 28%. The study is completed with an analysis of false positives to explain this precision value. We think that our results support the claim that our lexical approach can contribute to the axiomatic enrichment of biomedical ontologies and that it can provide new insights into the engineering of

  15. Expression of interferon and interferon--induced genes in Atlantic salmon Salmo salar cell lines SHK-1 and TO following infection with Salmon AlphaVirus SAV.

    Science.gov (United States)

    Gahlawat, Suresh K; Ellis, Anthony E; Collet, Bertrand

    2009-04-01

    Salmon AlphaVirus (SAV) is the aetiological agent of Salmon Pancreas Disease (SPD), a serious disease in farmed Atlantic salmon. Currently there is no available information on the ability of this virus to stimulate or suppress aspects of innate immunity in host cells. Two different Atlantic salmon cell lines (SHK-1 and TO), both derived from head kidney leucocytes, were infected with SAV and the kinetics and magnitude of gene expression were studied by real-time quantitative PCR. SAV nsP1 gene transcripts for strain P42P increased rapidly in TO cells with subsequent development of a cytopathic effect (CPE) while this virus strain hardly replicated at all SHK-1 cells causing no CPE. SAV P42P induced strong expression of type I IFN (IFN) and the antiviral IFN-induced gene MX transcripts in SHK-1 cells. Although the IFN response in infected TO cells was higher than in SHK-1 cells, the level of MX transcripts was lower. This may be because the virus was able to interfere with IFN-signaling and suppress MX transcription or that the TO cells are less able to transcribe the MX gene. Either way, it may account for why the SHK-1 cells suppress SAV replication while the TO cells are highly susceptible and succumb to the virus. The present results provide the first evidence for differential induction of expression of the interferon-induced antiviral gene, MX, correlating with resistant (SHK-1) and susceptible (TO) Atlantic salmon cell lines in response to infection by SAV.

  16. Studying Genes

    Science.gov (United States)

    ... NIGMS NIGMS Home > Science Education > Studying Genes Studying Genes Tagline (Optional) Middle/Main Content Area Other Fact Sheets What are genes? Genes are segments of DNA that contain instructions ...

  17. O-antigen structure of Shigella flexneri serotype Yv and effect of the lpt-O gene variation on phosphoethanolamine modification of S. flexneri O-antigens.

    Science.gov (United States)

    Knirel, Yuriy A; Lan, Ruiting; Senchenkova, Sof'ya N; Wang, Jianping; Shashkov, Alexander S; Wang, Yan; Perepelov, Andrei V; Xiong, Yanwen; Xu, Jianguo; Sun, Qiangzheng

    2013-04-01

    Shigella flexneri is the major human pathogen causing shigellosis. O-antigens of all S. flexneri serotypes (except for serotype 6) share the →2)-α-l-Rhap(III)-(1 → 2)-α-l-Rhap(II)-(1 → 3)-α-l-Rhap(I)-(1 → 3)-β-d-GlcpNAc-(1→ basic O-unit, whereas differences between the serotypes are conferred by phage-encoded glucosylation and/or O-acetylation at various positions. Recently, in serotype X and 4a variants called Xv and 4av, respectively, O-antigen modification with phosphoethanolamine (PEtN) has been identified, which is encoded by a plasmid-borne gene (lpt-O) for a PEtN-transferase and confers the monoclonal antibody IV-1(MASF IV-1) determinant to the bacteria. In this study, we elucidated the O-antigen structure of serotype Yv, another MASF IV-1-positive novel variant of S. flexneri. The serotype Yv O-antigen has the same basic carbohydrate backbone structure as that of the "classical" serotype Y, but differs in the presence of PEtN at position 3 of Rha(III) (major) or both Rha(II) and Rha(III) (minor). This pattern is similar to that of serotype 4av, but different from the pattern of serotype Xv, which is characterized by major PEtN modification on Rha(II). In serotype Yv, mono- and bisphosphorylated O-units generate a block-copolymeric structure, the former being partially O-acetylated at position 6 of GlcNAc and the latter lacking O-acetylation. Functional analysis revealed a correlation between the serotype-specific PEtN modification pattern and the lpt-O variation in different serotypes: lpt-O(RII) in serotype Xv is better tuned for phosphorylation of Rha(II) and lpt-O(RIII) in serotypes Yv and 4av for phosphorylation of Rha(III). These data enhance our knowledge of S. flexneri serotype conversion mechanisms and help to understand the biosynthesis process of the new O-antigen variants.

  18. Further EST analysis of endocrine genes that are preferentially expressed in the neural complex of Ciona intestinalis: receptor and enzyme genes associated with endocrine system in the neural complex.

    Science.gov (United States)

    Sekiguchi, Toshio; Kawashima, Takeshi; Satou, Yutaka; Satoh, Nori

    2007-01-15

    Identification of orthologs of vertebrate neuropeptides and hypothalamic hormones in the neural complex of ascidians suggests integral roles of the ascidian neural complex in the endocrine system. In the present study, we investigated endocrine-related genes expressed in the neural complex of Ciona intestinalis. Comprehensive analyses of 3'-end sequences of the neural complex cDNAs placed 10,029 clones into 4051 independent clusters or genes, 1524 of them being expressed preferentially in this organ. Comparison of the 1524 genes with the human proteome databank demonstrated that 476 matched previously identified human proteins with distinct functions. Further analyses of sequence similarity of the 476 genes demonstrated that 21 genes are candidates for those involved in the endocrine system. Although we cannot detect hormone or peptide candidates, we found 21 genes such as receptors for peptide ligands, receptor-modulating proteins, and processing enzymes. We then characterized the Ciona prohormone convertase 2 (Ci-PC2) and carboxypeptidase E (Ci-CPE), which are associated with endoproteolytic processing of peptide hormone precursors. Furthermore, genes encoding these transcripts are expressed specifically in the neural complex of young adult ascidians. These data provide the molecular basis for further functional studies of the endocrine role of the neural complex of ascidians.

  19. 伪狂犬病病毒主要毒力基因对其致细胞病变能力的影响%Effects of main virulent genes of pseudorabies virus on their cytopathogenicity

    Institute of Scientific and Technical Information of China (English)

    朱玲; 郭万柱; 王印; 阳爱国; 石恬; 徐凯; 赵玲

    2009-01-01

    The TK-deleted strain,the gI-gE-deleted strain and the TK-gI-gE-deleted strain of pseudo-rabies virus(PRV) and a PRV Fa strain were used to infect IBRS-2, Marc-145 ,ST,Vero and MDBK cells at dosage of 0.5 mL(1×10~6 PFU/mL). The cellular morphometric changes were observed at hours 0,8,12, 24,36 and 48 post-infection, respectively. All the four strains of virus could proliferate and induce cytopath-ic effect(CPE) on the five cell lines, but there was diversity in the emergence time and characteristics of CPE among them. The CPE resulted from PRV Fa strain was more serious than those from the other 3 strains. The results indicated that different virulence genes of PRV possessed different ability of CPE.%以伪狂犬病病毒(PRV)Fa株为对照,时PRV Fa株TK基因缺失株、PRV Fa株gI/gE双基因缺失株和PRV Fa株TK/gI/gE三基因缺失株进行了细胞培养特性的观察.包括对照毒株在内的4个毒株均按0.5 mL(1×10~6PFU)接种量分别感染IBRS-2、Marc-145、ST、Vero和MDBK等细胞系;选择在接种后第0、8、12、24、36和48 h观察感染细胞的形态学变化.结果显示,这4个毒株在这5种细胞上均能增殖并引起细胞病变,但PRV基因缺失株引起的病变程度均不及Fa株.表明,PRV的不同毒力基因对其致细胞病变能力不同.

  20. Immunoglobulin genes

    Energy Technology Data Exchange (ETDEWEB)

    Honjo, T. (Kyoto Univ. (Japan)); Alt, F.W. (Columbia Univ., Dobbs Ferry, NY (USA). Hudson Labs.); Rabbitts, T.H. (Medical Research Council, Cambridge (UK))

    1989-01-01

    This book reports on the structure, function, and expression of the genes encoding antibodies in normal and neoplastic cells. Topics covered are: B Cells; Organization and rearrangement of immunoglobin genes; Immunoglobin genes in disease; Immunoglobin gene expression; and Immunoglobin-related genes.

  1. Antimicrobial susceptibility testing in predicting the presence of carbapenemase genes in Enterobacteriaceae in South Africa.

    Science.gov (United States)

    Singh-Moodley, Ashika; Perovic, Olga

    2016-10-04

    Carbapenem-resistant Enterobacteriaceae (CRE) is a concern in South Africa and worldwide. It is therefore important that these organisms be accurately identified for infection prevention control purposes. In this study 1193 suspected CREs from 46 laboratories from seven provinces in South Africa were assessed to confirm the prevalence of carbapenemase genes from our referral diagnostic isolates for the period 2012 to 2015. We compared the antimicrobial susceptibility testing method used in the reference laboratory to the polymerase chain reaction (PCR) which is used as the gold standard. Organism identification and antimicrobial susceptibility testing were performed using automated systems and DNA was extracted using a crude boiling method. The presence of carbapenemase-producing genes (bla NDM, bla KPC, bla OXA-48&variants, bla GES, bla IMP and bla VIM) was screened for using a multiplex real-time PCR. Sixty-eight percent (n = 812) of the isolates harboured a carbapenemase-producing gene; the three most common genes included: bla NDM, bla OXA-48&variants and bla VIM. Majority of the carbapenemase producing Enterobacteriaceae (CPE) isolates were Klebsiella species (71 %). The Microscan® Walkaway system used for the screening of carbapenemase production was 98 % sensitive with a minimal inhibitory concentration (MIC) breakpoint of less than 0.5 as susceptible for ertapenem and a low specificity (13 %). From this study we can conclude that carbapenemase-producing Enterobacteriaceae is increasing in South Africa and the use of phenotypic methods for detection of CPEs showed good sensitivity but lacked specificity.

  2. OPTN gene: profile of patients with glaucoma from India.

    Science.gov (United States)

    Sripriya, S; Nirmaladevi, J; George, R; Hemamalini, A; Baskaran, M; Prema, R; Ve Ramesh, S; Karthiyayini, T; Amali, J; Job, S; Vijaya, L; Kumaramanickavel, G

    2006-07-24

    Optineurin gene (OPTN) mutations are reported in primary open angle glaucoma patients (POAG) from different populations. The coding and noncoding regions of OPTN were screened for mutations in 100 Indian high tension glaucoma patients (HTG). The frequency of the OPTN M98K mutation in an additional 120 patients (70 HTG and 50 normal tension glaucoma [NTG]) was analyzed by restriction enzyme digestion. The HTG patients (about 40 years of age) were characterized by open angles on gonioscopy, with raised intraocular pressure (IOP) more than 21 mmHg (A polymorphism was attempted with AliBaba software (version 2.1). Six sequence alterations were observed in the 100 POAG patients by direct sequencing. The M98K substitution was observed in a total of 10 patients (7/170 HTG and 3/50 NTG) contributing to 4.1% in HTG and 6% in the NTG group and not in the controls. The IVS7+24G>A nucleotide change showed a significant difference in the HTG group (7/100) when compared to the control group (0/100) and found to be associated with increased IOP at diagnosis (p=0.03). The IVS7+24G>A polymorphism resulted in the creation of binding sites for transcription factors NF-1 and CPE that were not present in the wild type. The current study suggests a possible role of SNPs rather than mutations in OPTN in POAG pathology in the Indian population.

  3. Characterization and functional analysis of seven flagellin genes in Rhizobium leguminosarum bv. viciae. Characterization of R. leguminosarum flagellins

    Directory of Open Access Journals (Sweden)

    Tambalo Dinah D

    2010-08-01

    Full Text Available Abstract Background Rhizobium leguminosarum bv. viciae establishes symbiotic nitrogen fixing partnerships with plant species belonging to the Tribe Vicieae, which includes the genera Vicia, Lathyrus, Pisum and Lens. Motility and chemotaxis are important in the ecology of R. leguminosarum to provide a competitive advantage during the early steps of nodulation, but the mechanisms of motility and flagellar assembly remain poorly studied. This paper addresses the role of the seven flagellin genes in producing a functional flagellum. Results R. leguminosarum strains 3841 and VF39SM have seven flagellin genes (flaA, flaB, flaC, flaD, flaE, flaH, and flaG, which are transcribed separately. The predicted flagellins of 3841 are highly similar or identical to the corresponding flagellins in VF39SM. flaA, flaB, flaC, and flaD are in tandem array and are located in the main flagellar gene cluster. flaH and flaG are located outside of the flagellar/motility region while flaE is plasmid-borne. Five flagellin subunits (FlaA, FlaB, FlaC, FlaE, and FlaG are highly similar to each other, whereas FlaD and FlaH are more distantly related. All flagellins exhibit conserved amino acid residues at the N- and C-terminal ends and are variable in the central regions. Strain 3841 has 1-3 plain subpolar flagella while strain VF39SM exhibits 4-7 plain peritrichous flagella. Three flagellins (FlaA/B/C and five flagellins (FlaA/B/C/E/G were detected by mass spectrometry in the flagellar filaments of strains 3841 and VF39SM, respectively. Mutation of flaA resulted in non-motile VF39SM and extremely reduced motility in 3841. Individual mutations of flaB and flaC resulted in shorter flagellar filaments and consequently reduced swimming and swarming motility for both strains. Mutant VF39SM strains carrying individual mutations in flaD, flaE, flaH, and flaG were not significantly affected in motility and filament morphology. The flagellar filament and the motility of 3841 strains

  4. Detection of bar gene encoding phosphinothricin herbicide resistance in plants by electrochemical biosensor.

    Science.gov (United States)

    Ligaj, Marta; Tichoniuk, Mariusz; Filipiak, Marian

    2008-11-01

    An electrochemical biosensor for the detection of bar gene coding phosphinothricin herbicide resistance is presented. The detection was based on hybridization reaction between the specific to bar gene 19-mer probe immobilized on the electrode surface and complementary DNA in a sample. Single-stranded DNA probe specific to bar gene was covalently attached by 5'-phosphate end to the surface of carbon paste electrode. Outer layer of a conventional CPE was provided with carboxyl groups of stearic acid. ssDNA was coupled to the electrode through ethylenediamine with the use of water-soluble 1-ethyl-3(3'-dimethylaminopropyl)-carbodiimide and N-hydroxy-sulfosuccinimide as activating reagents. Hybridization reaction at the electrode surface was detected via Co(bpy)(3)(3+), which possess a much higher affinity to the resulting DNA duplex compared to ssDNA probe. Detection limit of the sensor was 0.1 microM of target DNA fragments and its response was linear from 5 to 20 microM. Hybridization event was also detected by measuring guanine peak but this approach presented distinctly higher detection limit (1 muM) and lower reproducibility. Complete time of one measurement with the use of the biosensor including covalent attachment of ethylenediamine (linker) and ssDNA probe to the electrode, hybridization with target and interaction with electroactive indicator was about 70 min.

  5. Identification and nitrogen regulation of the cyanase gene from the cyanobacteria Synechocystis sp. strain PCC 6803 and Synechococcus sp. strain PCC 7942.

    OpenAIRE

    Harano, Y; Suzuki, I.; Maeda, S; Kaneko, T.; Tabata, S; Omata, T

    1997-01-01

    An open reading frame (slr0899) on the genome of Synechocystis sp. strain PCC 6803 encodes a polypeptide of 149 amino acid residues, the sequence of which is 40% identical to that of cyanase from Escherichia coli. Introduction into a cyanase-deficient E. coli strain of a plasmid-borne slr0899 resulted in expression of low but significant activity of cyanase. Targeted interruption of a homolog of slr0899 from Synechococcus sp. strain PCC 7942, encoding a protein 77% identical to that encoded b...

  6. Expression of energy metabolism related genes in the gastric tissue of obese individuals with non-alcoholic fatty liver disease.

    Science.gov (United States)

    Mehta, Rohini; Birerdinc, Aybike; Wang, Lei; Younoszai, Zahra; Moazzez, Amir; Elariny, Hazem; Goodman, Zachary; Chandhoke, Vikas; Baranova, Ancha; Younossi, Zobair M

    2014-04-09

    Stomach is an integral part of the energy balance regulating circuit. Studies exploring the effects of cross-system changes in the energy homeostasis in stomach tissue are scarce. The proximity of the stomach to liver--the most common secondary target affected by obesity--suggests that these two organs are exposed to each other's local secretion. Therefore, we aimed at expression profiling of energy metabolism associated genes in the gastric tissue of obese non-alcoholic fatty liver disease (NAFLD) patients. A total of 24 patients with histologically-proven NAFLD were included. In the gastric tissue, gene expression profiling of 84 energy metabolism associated genes was carried out. The accumulation of the fat in the liver parenchyma is accompanied by downregulation of genes encoding for carboxypeptidase E (CPE) and Interleukin 1B (IL1B) in the gastric mucosa of same patient. In patients with high grade hepatic steatosis, Interleukin 1 beta encoding gene with anorexigenic function, IL1B was downregulated. The levels expression of 21 genes, including ADRA2B, CNR1 and LEP were significantly altered in the gastric tissue of NAFLD patients with hepatic inflammation. There were also indications of an increase in the opioid signaling within gastric mucosa that may results in a shift to proinflammatory environment within this organ and contribute to systemic inflammation and the pathogenic processes in hepatic parenchyma. We have shown differential expression of energy metabolism associated genes in the gastric tissue of obese NAFLD patients. Importantly, these gene expression profiles are associated with changes in the hepatic parenchyma as reflected in increased scores for hepatic steatosis, inflammation, fibrosis and NASH. This study suggests the complex interplay of multiple organs in the pathogenesis of obesity-related complications such as NAFLD and provides further evidence supporting an important role for gastric tissue in promoting obesity-related complications.

  7. Gene therapy

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    2005147 CNHK200-hA-a gene-viral therapeutic system and its antitumor effect on lung cancer. WANG Wei-guo(王伟国),et al. Viral & Gene Ther Center, Eastern Hepatobilli Surg Instit 2nd Milit Univ, Shanghai 200438. Chin J Oncol,2005:27(2):69-72. Objective: To develop a novel vector system, which combines the advantages of the gene therapy,

  8. Trichoderma genes

    Science.gov (United States)

    Foreman, Pamela [Los Altos, CA; Goedegebuur, Frits [Vlaardingen, NL; Van Solingen, Pieter [Naaldwijk, NL; Ward, Michael [San Francisco, CA

    2012-06-19

    Described herein are novel gene sequences isolated from Trichoderma reesei. Two genes encoding proteins comprising a cellulose binding domain, one encoding an arabionfuranosidase and one encoding an acetylxylanesterase are described. The sequences, CIP1 and CIP2, contain a cellulose binding domain. These proteins are especially useful in the textile and detergent industry and in pulp and paper industry.

  9. Gene Therapy.

    Science.gov (United States)

    Thorne, Barb; Takeya, Ryan; Vitelli, Francesca; Swanson, Xin

    2017-03-14

    Gene therapy refers to a rapidly growing field of medicine in which genes are introduced into the body to treat or prevent diseases. Although a variety of methods can be used to deliver the genetic materials into the target cells and tissues, modified viral vectors represent one of the more common delivery routes because of its transduction efficiency for therapeutic genes. Since the introduction of gene therapy concept in the 1970s, the field has advanced considerably with notable clinical successes being demonstrated in many clinical indications in which no standard treatment options are currently available. It is anticipated that the clinical success the field observed in recent years can drive requirements for more scalable, robust, cost effective, and regulatory-compliant manufacturing processes. This review provides a brief overview of the current manufacturing technologies for viral vectors production, drawing attention to the common upstream and downstream production process platform that is applicable across various classes of viral vectors and their unique manufacturing challenges as compared to other biologics. In addition, a case study of an industry-scale cGMP production of an AAV-based gene therapy product performed at 2,000 L-scale is presented. The experience and lessons learned from this largest viral gene therapy vector production run conducted to date as discussed and highlighted in this review should contribute to future development of commercial viable scalable processes for vial gene therapies.

  10. Draft Genome Sequence of the blaOXA-436- and blaNDM-1-Harboring Shewanella putrefaciens SA70 Isolate.

    Science.gov (United States)

    Potter, Robert F; D'Souza, Alaric W; Wallace, Meghan A; Shupe, Angela; Patel, Sanket; Gul, Danish; Kwon, Jennie H; Andleeb, Saadia; Burnham, C A; Dantas, Gautam

    2017-07-20

    We sequenced a carbapenem-resistant Shewanella putrefaciens isolate cultured from the sink handle of a Pakistan hospital room. Assembly annotation indicates that the isolate has a chromosomal blaOXA-436 carbapenemase and a plasmid-borne blaNDM-1 gene. To our knowledge, this is the first report of a Shewanella species harboring blaNDM. Copyright © 2017 Potter et al.

  11. Evolution of a Heavy Metal Homeostasis/Resistance Island Reflects Increasing Copper Stress in Enterobacteria

    OpenAIRE

    Staehlin, Benjamin M; Gibbons, John G.; Rokas, Antonis; O'Halloran, Thomas V.; Slot, Jason C.

    2016-01-01

    Copper homeostasis in bacteria is challenged by periodic elevation of copper levels in the environment, arising from both natural sources and human inputs. Several mechanisms have evolved to efflux copper from bacterial cells, including the cus (copper sensing copper efflux system), and pco (plasmid-borne copper resistance system) systems. The genes belonging to these two systems can be physically clustered in a Copper Homeostasis and Silver Resistance Island (CHASRI) on both plasmids and chr...

  12. Gene Therapy

    Science.gov (United States)

    ... or improve your body's ability to fight disease. Gene therapy holds promise for treating a wide range of diseases, such as cancer, cystic fibrosis, heart disease, diabetes, hemophilia and AIDS. Researchers are still studying how and ...

  13. Genes V.

    Energy Technology Data Exchange (ETDEWEB)

    Lewin, B.

    1994-12-31

    This fifth edition book encompasses a wide range of topics covering 1,272 pages. The book is arranged into nine parts with a total of 36 chapters. These nine parts include Introduction; DNA as a Store of Information; Translation; Constructing Cells; Control of Prokaryotypic Gene Expression; Perpetuation of DNA; Organization of the Eukaryotypic Genome; Eukaryotypic Transcription and RNA Processing; The Dynamic Genome; and Genes in Development.

  14. Genetic characterization of type A enterotoxigenic Clostridium perfringens strains.

    Directory of Open Access Journals (Sweden)

    Agi Deguchi

    Full Text Available Clostridium perfringens type A, is both a ubiquitous environmental bacterium and a major cause of human gastrointestinal disease, which usually involves strains producing C. perfringens enterotoxin (CPE. The gene (cpe encoding this toxin can be carried on the chromosome or a large plasmid. Interestingly, strains carrying cpe on the chromosome and strains carrying cpe on a plasmid often exhibit different biological characteristics, such as resistance properties against heat. In this study, we investigated the genetic properties of C. perfringens by PCR-surveying 21 housekeeping genes and genes on representative plasmids and then confirmed those results by Southern blot assay (SB of five genes. Furthermore, sequencing analysis of eight housekeeping genes and multilocus sequence typing (MLST analysis were also performed. Fifty-eight C. perfringens strains were examined, including isolates from: food poisoning cases, human gastrointestinal disease cases, foods in Japan or the USA, or feces of healthy humans. In the PCR survey, eight of eleven housekeeping genes amplified positive reactions in all strains tested. However, by PCR survey and SB assay, one representative virulence gene, pfoA, was not detected in any strains carrying cpe on the chromosome. Genes involved in conjugative transfer of the cpe plasmid were also absent from almost all chromosomal cpe strains. MLST showed that, regardless of their geographic origin, date of isolation, or isolation source, chromosomal cpe isolates, i assemble into one definitive cluster ii lack pfoA and iii lack a plasmid related to the cpe plasmid. Similarly, independent of their origin, strains carrying a cpe plasmid also appear to be related, but are more variable than chromosomal cpe strains, possibly because of the instability of cpe-borne plasmid(s and/or the conjugative transfer of cpe-plasmid(s into unrelated C. perfringens strains.

  15. Light-dependent attenuation of phycoerythrin gene expression reveals convergent evolution of green light sensing in cyanobacteria.

    Science.gov (United States)

    Bezy, Ryan P; Wiltbank, Lisa; Kehoe, David M

    2011-11-08

    The colorful process of chromatic acclimation allows many cyanobacteria to change their pigmentation in response to ambient light color changes. In red light, cells produce red-absorbing phycocyanin (PC), whereas in green light, green-absorbing phycoerythrin (PE) is made. Controlling these pigment levels increases fitness by optimizing photosynthetic activity in different light color environments. The light color sensory system controlling PC expression is well understood, but PE regulation has not been resolved. In the filamentous cyanobacterium Fremyella diplosiphon UTEX 481, two systems control PE synthesis in response to light color. The first is the Rca pathway, a two-component system controlled by a phytochrome-class photoreceptor, which transcriptionally represses cpeCDESTR (cpeC) expression during growth in red light. The second is the Cgi pathway, which has not been characterized. We determined that the Cgi system also regulates PE synthesis by repressing cpeC expression in red light, but acts posttranscriptionally, requiring the region upstream of the CpeC translation start codon. cpeC RNA stability was comparable in F. diplosiphon cells grown in red and green light, and a short transcript that included the 5' region of cpeC was detected, suggesting that the Cgi system operates by transcription attenuation. The roles of four predicted stem-loop structures within the 5' region of cpeC RNA were analyzed. The putative stem-loop 31 nucleotides upstream of the translation start site was required for Cgi system function. Thus, the Cgi system appears to be a unique type of signal transduction pathway in which the attenuation of cpeC transcription is regulated by light color.

  16. DREB genes

    African Journals Online (AJOL)

    Unipar

    2015-03-12

    Mar 12, 2015 ... to AP2/ERF family, dehydration-responsive element-binding protein (DREB) genes, (CitsERF01 to ... Protein sequences of DREB subfamilies belonging to group I, .... position 37, and it was present in consensus in all protein.

  17. Incorporation of a Cationic Conjugated Polyelectrolyte CPE within an Aqueous Poly(vinyl alcohol) Sol

    DEFF Research Database (Denmark)

    Knaapila, Matti; Stewart, Beverly; Costa, Telma

    2016-01-01

    We report on a multiscale polymer-within-polymer structure of the cationic conjugated polyelectrolyte poly{[9,9-bis(6-N,N,N-trimethylammonium)hexyl]fluorene phenylene} (HTMAPFP) in aqueous poly(vinyl alcohol).(PVA) sol. Molecular dynamics simulations and small-angle neutron scattering (SANS) data...

  18. PVC/特种CPE的共混增韧%Blended Toughening of PVC/Special CPE

    Institute of Scientific and Technical Information of China (English)

    杜壮; 徐超; 闫志佩; 赵季若; 冯莺

    2011-01-01

    The special chlorinated polyethylene was synthesized from high density polyethylene(HDPE) through solid phase method,in which a new kind chlorinated polyethylene(CPE) with special chlorine distribution was obtained by controlling temperature and time of the chlorinating reaction.The special chlorinated polyethylene(SCPE) can be used as a new modifier to toughen poly(vinyl chloride)(PVC).In this article,the mechanical property and microcosmic structure of SCPE and the blended system were studied.The results show that tensile strength of the blends increases 4% and notch impact strength of the blends increases 62.5% contrast to pure PVC.Results of DSC and 1H-NMR indicate that chain segments of different chlorine content exist in molecular chains of SCPE.The toughness of PVC can be modified by SCPE blended onto PVC while tensile strength of blends is improved.The analysis of morphological structure shows that the sufficient amalgamation between PVC phase and SCPE phase is excellent to improve mechanical property of the blends.%采用固相法对高密度聚乙烯(HDPE)进行氯化,得到分子链上具有特殊氯分布的特种氯化聚乙烯(CPE)(SCPE),其可以作为增韧剂对聚氯乙烯(PVC)增韧。结果表明,在SCPE含量为5份时,PVC/SCPE共混物的拉伸强度相对于PVC没有降低,反而提高了4%左右;缺口冲击强度提高了62.5%(13 kJ/m2)。差示扫描量热(DSC)和核磁共振(1H-NMR)的结果表明,SCPE分子链上特殊的氯嵌段结构对材料的性能至关重要。材料断面扫描电镜(SEM)分析表明PVC相与SCPE相的充分融合是力学性能优异的原因之一。

  19. The effect of artificial accelerated weathering on the mechanical properties of maxillofacial polymers PDMS and CPE

    Energy Technology Data Exchange (ETDEWEB)

    Eleni, P N; Krokida, M K [Department of Chemical Engineering, National Technical University of Athens, Zografou, Campus, 15780 Athens (Greece); Polyzois, G L [Division of Removable Prosthodontics, University of Athens, Dental School, 2 Thivon Street, 11527 Athens (Greece)

    2009-06-15

    The effect of UVA-UVB irradiation on the mechanical properties of three different industrial types of polydimethylsiloxane and chlorinated polyethylene samples, used in maxillofacial prostheses, was investigated in this study. Mechanical properties and thermal analysis are commonly used to determine the structural changes and mechanical strength. An aging chamber was used in order to simulate the solar radiation and assess natural aging. Compression and tensile tests were conducted on a Zwick testing machine. Durometer Shore A hardness measurements were carried out in a CV digital Shore A durometer according to ASTM D 2240. Glass transition temperature was evaluated with a differential scanning calorimeter. Simple mathematical models were developed to correlate the measured properties with irradiation time. The effect of UVA-UVB irradiation on compressive behavior affected model parameters. Significant deterioration seems to occur due to irradiation in samples.

  20. Endothelial Genes

    Science.gov (United States)

    2005-06-01

    8217Department of Surgery, Division of Oncology , and 2Department of BRCA-l and BRCA-2 (breast cancer susceptibility genes), Pathology, University of...Suppression subtractive hybridization re- Cancer: principles and practice of oncology . Philadelphia: Lippincott- vealed an RNA sequence (GenBank accession...Lippman ME. Cancer of the breast: molecular biology angiogenesis in sarcomas and carcinomas. Clin Cancer Res 1999;5: of breast cancer. In: DeVita VT

  1. Gene Ontology

    Directory of Open Access Journals (Sweden)

    Gaston K. Mazandu

    2012-01-01

    Full Text Available The wide coverage and biological relevance of the Gene Ontology (GO, confirmed through its successful use in protein function prediction, have led to the growth in its popularity. In order to exploit the extent of biological knowledge that GO offers in describing genes or groups of genes, there is a need for an efficient, scalable similarity measure for GO terms and GO-annotated proteins. While several GO similarity measures exist, none adequately addresses all issues surrounding the design and usage of the ontology. We introduce a new metric for measuring the distance between two GO terms using the intrinsic topology of the GO-DAG, thus enabling the measurement of functional similarities between proteins based on their GO annotations. We assess the performance of this metric using a ROC analysis on human protein-protein interaction datasets and correlation coefficient analysis on the selected set of protein pairs from the CESSM online tool. This metric achieves good performance compared to the existing annotation-based GO measures. We used this new metric to assess functional similarity between orthologues, and show that it is effective at determining whether orthologues are annotated with similar functions and identifying cases where annotation is inconsistent between orthologues.

  2. Functional studies of the gene slr2049 from Synechocystis sp. PCC6803 and its site-directed mutation.

    Science.gov (United States)

    Liu, Bingjun; Chen, Sili; Zhang, Lei

    2015-06-01

    Phycobiliprotein is a homologous family of light-harvesting chromoproteins existing in cyanobacteria, red algae and cryptophytes. Phycobiliprotein is made up of phycobilin and its corresponding apophycobiliprotein, and they are covalently linked by the thioether bond with the bilin lyase. Using the software BLAST, we have found gene slr2049 in Synechocystis sp. PCC6803 homologous to the biliprotein lyase gene cpeS. This paper investigates the protein expressed by gene slr2049 to find the enzymatic activity characteristics. We cloned slr2049 and its related genes cpcB, ho1, and pcyA which are linked with the synthesis of phycocyanin. Special amino acid mutagenesis was performed on slr2049 to construct eight mutants slr2049 (H21S), slr2049 (L23S), slr2049 (A24S), slr2049 (F25S), slr2049 (W72L), slr2049 (G84S), slr2049 (R107S) and slr2049 (Y124S). These mutants were ligated with vectors pEDFDuet-1 and pET-23a to construct pCDF-cpcB-slr2049 wild-type, pCDF-cpcB-slr2049 mutants and pET-ho1-pcyA, for the purpose of protein expression and analysis. The results showed that the wild-type and mutants slr2049 (H21S), slr2049 (L23S), slr2049 (F25S), slr2049 (W72L), slr2049 (G84S), and slr2049 (Y124S) can catalyze CpcB to couple on PCB correctly and the products have unique spectral characteristics. However mutants slr2049 (A24S) and slr2049 (R107S) have no spectral characteristics. Thus, it is suggested that alanine at position 24 and arginine at position 107 are the active sites.

  3. Gene doping: gene delivery for olympic victory

    OpenAIRE

    2012-01-01

    With one recently recommended gene therapy in Europe and a number of other gene therapy treatments now proving effective in clinical trials it is feasible that the same technologies will soon be adopted in the world of sport by unscrupulous athletes and their trainers in so called ‘gene doping’. In this article an overview of the successful gene therapy clinical trials is provided and the potential targets for gene doping are highlighted. Depending on whether a doping gene product is secreted...

  4. Carbapenemase-producing Enterobacteriaceae in Europe: assessment by national experts from 38 countries, May 2015.

    Science.gov (United States)

    Albiger, Barbara; Glasner, Corinna; Struelens, Marc J; Grundmann, Hajo; Monnet, Dominique L

    2015-01-01

    In 2012, the European Centre for Disease Prevention and Control (ECDC) launched the 'European survey of carbapenemase-producing Enterobacteriaceae (EuSCAPE)' project to gain insights into the occurrence and epidemiology of carbapenemase-producing Enterobacteriaceae (CPE), to increase the awareness of the spread of CPE, and to build and enhance the laboratory capacity for diagnosis and surveillance of CPE in Europe. Data collected through a post-EuSCAPE feedback questionnaire in May 2015 documented improvement compared with 2013 in capacity and ability to detect CPE and identify the different carbapenemases genes in the 38 participating countries, thus contributing to their awareness of and knowledge about the spread of CPE. Over the last two years, the epidemiological situation of CPE worsened, in particular with the rapid spread of carbapenem-hydrolysing oxacillinase-48 (OXA-48)- and New Delhi metallo-beta-lactamase (NDM)-producing Enterobacteriaceae. In 2015, 13/38 countries reported inter-regional spread of or an endemic situation for CPE, compared with 6/38 in 2013. Only three countries replied that they had not identified one single case of CPE. The ongoing spread of CPE represents an increasing threat to patient safety in European hospitals, and a majority of countries reacted by establishing national CPE surveillances systems and issuing guidance on control measures for health professionals. However, 14 countries still lacked specific national guidelines for prevention and control of CPE in mid-2015.

  5. PSG gene expression is up-regulated by lysine acetylation involving histone and nonhistone proteins.

    Directory of Open Access Journals (Sweden)

    Soledad A Camolotto

    Full Text Available BACKGROUND: Lysine acetylation is an important post-translational modification that plays a central role in eukaryotic transcriptional activation by modifying chromatin and transcription-related factors. Human pregnancy-specific glycoproteins (PSG are the major secreted placental proteins expressed by the syncytiotrophoblast at the end of pregnancy and represent early markers of cytotrophoblast differentiation. Low PSG levels are associated with complicated pregnancies, thus highlighting the importance of studying the mechanisms that control their expression. Despite several transcription factors having been implicated as key regulators of PSG gene family expression; the role of protein acetylation has not been explored. METHODOLOGY/PRINCIPAL FINDINGS: Here, we explored the role of acetylation on PSG gene expression in the human placental-derived JEG-3 cell line. Pharmacological inhibition of histone deacetylases (HDACs up-regulated PSG protein and mRNA expression levels, and augmented the amount of acetylated histone H3 associated with PSG 5'regulatory regions. Moreover, PSG5 promoter activation mediated by Sp1 and KLF6, via the core promoter element motif (CPE, -147/-140, was markedly enhanced in the presence of the HDAC inhibitor trichostatin A (TSA. This effect correlated with an increase in Sp1 acetylation and KLF6 nuclear localization as revealed by immunoprecipitation and subcellular fractionation assays. The co-activators PCAF, p300, and CBP enhanced Sp1-dependent PSG5 promoter activation through their histone acetylase (HAT function. Instead, p300 and CBP acetyltransferase domain was dispensable for sustaining co-activation of PSG5 promoter by KLF6. CONCLUSIONS/SIGNIFICANCE: Results are consistent with a regulatory role of lysine acetylation on PSG expression through a relaxed chromatin state and an increase in the transcriptional activity of Sp1 and KLF6 following an augmented Sp1 acetylation and KLF6 nuclear localization.

  6. Characterization of cathepsin B gene from orange-spotted grouper, Epinephelus coioides involved in SGIV infection.

    Science.gov (United States)

    Wei, Shina; Huang, Youhua; Huang, Xiaohong; Cai, Jia; Yan, Yang; Guo, Chuanyu; Qin, Qiwei

    2014-01-01

    The lysosomal cysteine protease cathepsin B of papain family is a key regulator and signaling molecule that involves in various biological processes, such as the regulation of apoptosis and activation of virus. In the present study, cathepsin B gene (Ec-CB) was cloned and characterized from orange-spotted grouper, Epinephelus coioides. The full-length Ec-CB cDNA was composed of 1918 bp and encoded a polypeptide of 330 amino acids with higher identities to cathepsin B of teleosts and mammalians. Ec-CB possessed typical cathepsin B structural features including an N-terminal signal peptide, the propeptide region and the cysteine protease domain which were conserved in other cathepsin B sequences. Phylogenetic analysis revealed that Ec-CB was most closely related to Lutjanus argentimaculatus. RT-PCR analysis showed that Ec-CB transcript was expressed in all the examined tissues which abundant in spleen, kidney and gill. After challenged with Singapore grouper iridovirus (SGIV) stimulation, the mRNA expression of cathepsin B in E. coioides was up-regulated at 24 h post-infection. Subcellular localization analysis revealed that Ec-CB was distributed predominantly in the cytoplasm. When the fish cells (GS or FHM) were treated with the cathepsin B specific inhibitor CA-074Me, the occurrence of CPE induced by SGIV was delayed, and the viral gene transcription was significantly inhibited. Additionally, SGIV-induced typical apoptosis was also inhibited by CA-074Me in FHM cells. Taken together, our results demonstrated that the Ec-CB might play a functional role in SGIV infection.

  7. Quantitative analysis of pigment gene expression in pigment mutants of Porphyra haitanensis%坛紫菜色素突变体色素基因的表达定量分析

    Institute of Scientific and Technical Information of China (English)

    黄惠珍; 谢潮添; 纪德华; 徐燕; 陈昌生

    2012-01-01

    Phycoerythrin (PE), phycocyanin (PC), allophycocyanin (APC), and chlorophyll a(Chl.a) are the four major photosynthetic pigments of Porphyra haitanensis. Their contents and ratio determine the blade color of Porphyra. In this study, the relative expressed levels of four pigment genes (Cpea, Cpca, Apcβ, and Chl.a) in different growth phases (early phase, bloom phase, and final phase) were determined using quantitative real-time PCR (qPCR) in one wild line and six pigment mutant lines of P. haitanensis. In all the lines, the relative expression levels of the four pigment genes were in the sequence: Apcβ>Cpca> Chl.d>Cpea. The expressed level of Cpea varied significantly in the different phases in all the lines; however, the expressions of Cpca, Apcβ, and Chl.a. were stable in all phases in all lines. Furthermore, liner correlation and regression analysis indicated that the expression levels of the pigment genes had no relation to the pigment protein contents in any of the lines. In other words, the expression levels of the four pigment genes had no relation to the differences in blade color among the Porphyra lines. Based on these results, we speculate that the pigment mutation of P. haitanensis was induced by mutations in genes that affect the synthesis of the pigment proteins.%以野生型和6种不同色泽的坛紫菜色素突变体为材料,通过实时荧光定量PCR技术分析了4种主要色素基因(Cpeα、Cpcα、Apcβ、Chl.a)在不同色泽突变体不同生长期(初期、盛期、末期)的相对表达水平.结果表明在不同色泽不同生长期的坛紫菜色素突变体中,各色素基因表达水平由高到低均为Apcββ>Cpcα>Chl.a>Cpeα,且Cpeα基因的表达水平最不稳定,会随着生长过程发生显著变化,而Cpcα、Apcβ和Chl.a基因表达水平则相对稳定;此外,对色素突变体和野生型藻体中色素基因表达水平和相应色素蛋白含量的线性相关回归分析结果表明二者间没有相关

  8. GeneEd -- A Genetics Educational Resource

    Science.gov (United States)

    ... Javascript on. Feature: Genetics 101 GeneEd — A Genetics Educational Resource Past Issues / Summer 2013 Table of Contents Science ... The Hereditary Material of Life / GeneEd — A Genetics Educational Resource / Using The Genetics Home Reference Website / Understanding the ...

  9. Evidence That the Enterotoxin Gene Can Be Episomal in Clostridium perfringens Isolates Associated with Non-Food-Borne Human Gastrointestinal Diseases

    OpenAIRE

    1998-01-01

    Clostridium perfringens enterotoxin (CPE) is responsible for the diarrheal and cramping symptoms of human C. perfringens type A food poisoning. CPE-producing C. perfringens isolates have also recently been associated with several non-food-borne human gastrointestinal (GI) illnesses, including antibiotic-associated diarrhea and sporadic diarrhea. The current study has used restriction fragment length polymorphism (RFLP) and pulsed-field gel electrophoresis (PFGE) analyses to compare the genoty...

  10. Molecular cloning and characterization of c-type lysozyme gene in orange-spotted grouper, Epinephelus coioides.

    Science.gov (United States)

    Wei, Shina; Huang, Youhua; Cai, Jia; Huang, Xiaohong; Fu, Jing; Qin, Qiwei

    2012-08-01

    Lysozymes are key proteins of the host innate immune system against pathogen infection. In this study, a c-type lysozyme gene (Ec-lysC) was cloned and characterized from orange-spotted grouper, Epinephelus coioides. The full-length Ec-lysC cDNA is composed of 533 bp and encodes a polypeptide of 144-residue protein with 94% identity to lysC of Kelp grouper, Epinephelus bruneus. The genomic DNA of Ec-lysC consists of 4 exons and 3 introns, with a total length of 1897 bp. Amino acid sequence alignment showed that Ec-lysC possessed conserved catalytic residues (Glu50 and Asp67) and "GSTDYGIFQINS" motif. RT-PCR results showed that Ec-lysC transcript was most abundant in head kidney and less in muscle. The expression of Ec-lysC was differentially up-regulated in head kidney after stimulation with lipopolysaccharide (LPS), Vibrio alginolyticus and Singapore grouper iridovirus (SGIV). Subcellular localization analysis revealed that Ec-lysC was distributed predominantly in the cytoplasm. The recombinant Ec-lysC (rEc-lysC) had lytic activities against Gram-positive bacteria Micrococcus lysodeikticus, Staphylococcus aureus, Streptococcus iniae and Gram-negative bacteria V. alginolyticus. The lysozyme acted on M. lysodeikticus cell walls as shown by scanning electron microscopy (SEM). Furthermore, overexpression of Ec-lysC in grouper cells delayed the occurrence of CPE induced by SGIV and inhibited the viral gene transcription significantly. Taken together, Ec-lysC might play an important role in grouper innate immune responses to invasion of bacterial and viral pathogens. C-type lysozyme gene from E. coioides (Ec-lysC) was identified and characterized.

  11. Special Issue: Gene Conversion in Duplicated Genes

    Directory of Open Access Journals (Sweden)

    Hideki Innan

    2011-06-01

    Full Text Available Gene conversion is an outcome of recombination, causing non-reciprocal transfer of a DNA fragment. Several decades later than the discovery of crossing over, gene conversion was first recognized in fungi when non-Mendelian allelic distortion was observed. Gene conversion occurs when a double-strand break is repaired by using homologous sequences in the genome. In meiosis, there is a strong preference to use the orthologous region (allelic gene conversion, which causes non-Mendelian allelic distortion, but paralogous or duplicated regions can also be used for the repair (inter-locus gene conversion, also referred to as non-allelic and ectopic gene conversion. The focus of this special issue is the latter, interlocus gene conversion; the rate is lower than allelic gene conversion but it has more impact on phenotype because more drastic changes in DNA sequence are involved.

  12. Principles of gene therapy

    OpenAIRE

    Mammen Biju; Ramakrishnan T; Sudhakar Uma; Vijayalakshmi

    2007-01-01

    Genes are specific sequences of bases that encode instructions to make proteins. When genes are altered so that encoded proteins are unable to carry out their normal functions, genetic disorders can result. Gene therapy is designed to introduce genetic material into cells to compensate for abnormal genes or to make a beneficial protein. This article reviews the fundamentals in gene therapy and its various modes of administration with an insight into the role of gene therapy in Periodontics an...

  13. Organization of immunoglobulin genes.

    Science.gov (United States)

    Tonegawa, S; Brack, C; Hozumi, N; Pirrotta, V

    1978-01-01

    The nucleotide-sequence determination of a cloned, embryonic Vlambda gene directly demonstrated that V genes are separate from a corresponding C gene in embryonic cells. Analysis by restriction enzymes of total cellular DNA from various sources strongly suggested that the two separate immunoglobulin genes become continuous during differentiation of B lymphocytes. There seems to be a strict correlation between the joining event and activation of the joined genes. Cloning of more immunoglobulin genes from embryo and plasma cells will not only provide direct demonstration of such a gene-joining event but also help in the elucidation of a possible relationship of the event to gene activation mechanisms.

  14. Characterization of the porcine carboxypeptidase E cDNA

    DEFF Research Database (Denmark)

    Hreidarsdôttir, G.E.; Cirera, Susanna; Fredholm, Merete

    2007-01-01

    the sequence of the cDNA for the porcine CPE gene including all the coding region and the 3'-UTR region was generated. Comparisons with bovine, human, mouse, and rat CPE cDNA sequences showed that the coding regions of the gene are highly conserved both at the nucleotide and at the amino acid level. A very low...

  15. Gene doping: gene delivery for olympic victory.

    Science.gov (United States)

    Gould, David

    2013-08-01

    With one recently recommended gene therapy in Europe and a number of other gene therapy treatments now proving effective in clinical trials it is feasible that the same technologies will soon be adopted in the world of sport by unscrupulous athletes and their trainers in so called 'gene doping'. In this article an overview of the successful gene therapy clinical trials is provided and the potential targets for gene doping are highlighted. Depending on whether a doping gene product is secreted from the engineered cells or is retained locally to, or inside engineered cells will, to some extent, determine the likelihood of detection. It is clear that effective gene delivery technologies now exist and it is important that detection and prevention plans are in place.

  16. The differential antiviral activities of chicken interferon α (ChIFN-α and ChIFN-β are related to distinct interferon-stimulated gene expression.

    Directory of Open Access Journals (Sweden)

    Hongren Qu

    Full Text Available Chicken interferon α (ChIFN-α and ChIFN-β are type I IFNs that are important antiviral cytokines in the innate immune system. In the present study, we identified the virus-induced expression of ChIFN-α and ChIFN-β in chicken fibroblast DF-1 cells and systematically evaluated the antiviral activities of recombinant ChIFN-α and ChIFN-β by cytopathic-effect (CPE inhibition assays. We found that ChIFN-α exhibited stronger antiviral activity than ChIFN-β in terms of inhibiting the replication of vesicular stomatitis virus, Newcastle disease virus and avian influenza virus, respectively. To elucidate the mechanism of differential antiviral activities between the two ChIFNs, we measured the relative mRNA levels of IFN-stimulated genes (ISGs in IFN-treated DF-1 cells by real-time PCR. ChIFN-α displayed greater induction potency than ChIFN-β on several ISGs encoding antiviral proteins and MHC-I, whereas ChIFN-α was less potent than ChIFN-β for inducing ISGs involved in signaling pathways. In conclusion, ChIFN-α and ChIFN-β presented differential induction potency on various sets of ISGs, and the stronger antiviral activity of ChIFN-α is likely attributed to the greater expression levels of downstream antiviral ISGs.

  17. Gene Cluster Statistics with Gene Families

    Science.gov (United States)

    Durand, Dannie

    2009-01-01

    Identifying genomic regions that descended from a common ancestor is important for understanding the function and evolution of genomes. In distantly related genomes, clusters of homologous gene pairs are evidence of candidate homologous regions. Demonstrating the statistical significance of such “gene clusters” is an essential component of comparative genomic analyses. However, currently there are no practical statistical tests for gene clusters that model the influence of the number of homologs in each gene family on cluster significance. In this work, we demonstrate empirically that failure to incorporate gene family size in gene cluster statistics results in overestimation of significance, leading to incorrect conclusions. We further present novel analytical methods for estimating gene cluster significance that take gene family size into account. Our methods do not require complete genome data and are suitable for testing individual clusters found in local regions, such as contigs in an unfinished assembly. We consider pairs of regions drawn from the same genome (paralogous clusters), as well as regions drawn from two different genomes (orthologous clusters). Determining cluster significance under general models of gene family size is computationally intractable. By assuming that all gene families are of equal size, we obtain analytical expressions that allow fast approximation of cluster probabilities. We evaluate the accuracy of this approximation by comparing the resulting gene cluster probabilities with cluster probabilities obtained by simulating a realistic, power-law distributed model of gene family size, with parameters inferred from genomic data. Surprisingly, despite the simplicity of the underlying assumption, our method accurately approximates the true cluster probabilities. It slightly overestimates these probabilities, yielding a conservative test. We present additional simulation results indicating the best choice of parameter values for data

  18. Cinnamon polyphenol extract regulates tristetraprolin and related gene expression in mouse adipocytes

    Science.gov (United States)

    Cinnamon (Cinnamomum verum) has been widely used in spices, flavoring agents, and preservatives. Cinnamon polyphenol extract (CPE) may be important in the alleviation of chronic diseases, but the molecular evidence is not substantial. Tristetraprolin (TTP) family proteins have anti-inflammatory ef...

  19. Lateral gene transfer, rearrangement, reconciliation

    NARCIS (Netherlands)

    Patterson, M.D.; Szollosi, G.; Daubin, V.; Tannier, E.

    2013-01-01

    Background. Models of ancestral gene order reconstruction have progressively integrated different evolutionary patterns and processes such as unequal gene content, gene duplications, and implicitly sequence evolution via reconciled gene trees. These models have so far ignored lateral gene transfer,

  20. Emergence of Carbapenem-Resistant Serotype K1 Hypervirulent Klebsiella pneumoniae Strains in China.

    Science.gov (United States)

    Zhang, Rong; Lin, Dachuan; Chan, Edward Wai-Chi; Gu, Danxia; Chen, Gong-Xiang; Chen, Sheng

    2015-11-16

    We report the emergence of five carbapenem-resistant K1 hypervirulent Klebsiella pneumoniae (hvKP) strains which caused fatal infections in hospital patients in Zhejiang Province, China, upon entry through surgical wounds. Genotyping results revealed the existence of three genetically related strains which exhibited a new sequence type, ST1797, and revealed that all strains harbored the magA and wcaG virulence genes and a plasmid-borne bla(KPC-2) gene. These findings indicate that K1 hvKP is simultaneously hypervirulent, multidrug resistant, and transmissible.

  1. Clostridium perfringens Enterotoxin: Action, Genetics, and Translational Applications.

    Science.gov (United States)

    Freedman, John C; Shrestha, Archana; McClane, Bruce A

    2016-03-16

    Clostridium perfringens enterotoxin (CPE) is responsible for causing the gastrointestinal symptoms of several C. perfringens food- and nonfood-borne human gastrointestinal diseases. The enterotoxin gene (cpe) is located on either the chromosome (for most C. perfringens type A food poisoning strains) or large conjugative plasmids (for the remaining type A food poisoning and most, if not all, other CPE-producing strains). In all CPE-positive strains, the cpe gene is strongly associated with insertion sequences that may help to assist its mobilization and spread. During disease, CPE is produced when C. perfringens sporulates in the intestines, a process involving several sporulation-specific alternative sigma factors. The action of CPE starts with its binding to claudin receptors to form a small complex; those small complexes then oligomerize to create a hexameric prepore on the membrane surface. Beta hairpin loops from the CPE molecules in the prepore assemble into a beta barrel that inserts into the membrane to form an active pore that enhances calcium influx, causing cell death. This cell death results in intestinal damage that causes fluid and electrolyte loss. CPE is now being explored for translational applications including cancer therapy/diagnosis, drug delivery, and vaccination.

  2. Clostridium perfringens Enterotoxin: Action, Genetics, and Translational Applications

    Directory of Open Access Journals (Sweden)

    John C. Freedman

    2016-03-01

    Full Text Available Clostridium perfringens enterotoxin (CPE is responsible for causing the gastrointestinal symptoms of several C. perfringens food- and nonfood-borne human gastrointestinal diseases. The enterotoxin gene (cpe is located on either the chromosome (for most C. perfringens type A food poisoning strains or large conjugative plasmids (for the remaining type A food poisoning and most, if not all, other CPE-producing strains. In all CPE-positive strains, the cpe gene is strongly associated with insertion sequences that may help to assist its mobilization and spread. During disease, CPE is produced when C. perfringens sporulates in the intestines, a process involving several sporulation-specific alternative sigma factors. The action of CPE starts with its binding to claudin receptors to form a small complex; those small complexes then oligomerize to create a hexameric prepore on the membrane surface. Beta hairpin loops from the CPE molecules in the prepore assemble into a beta barrel that inserts into the membrane to form an active pore that enhances calcium influx, causing cell death. This cell death results in intestinal damage that causes fluid and electrolyte loss. CPE is now being explored for translational applications including cancer therapy/diagnosis, drug delivery, and vaccination.

  3. Gene doping in sports.

    Science.gov (United States)

    Unal, Mehmet; Ozer Unal, Durisehvar

    2004-01-01

    Gene or cell doping is defined by the World Anti-Doping Agency (WADA) as "the non-therapeutic use of genes, genetic elements and/or cells that have the capacity to enhance athletic performance". New research in genetics and genomics will be used not only to diagnose and treat disease, but also to attempt to enhance human performance. In recent years, gene therapy has shown progress and positive results that have highlighted the potential misuse of this technology and the debate of 'gene doping'. Gene therapies developed for the treatment of diseases such as anaemia (the gene for erythropoietin), muscular dystrophy (the gene for insulin-like growth factor-1) and peripheral vascular diseases (the gene for vascular endothelial growth factor) are potential doping methods. With progress in gene technology, many other genes with this potential will be discovered. For this reason, it is important to develop timely legal regulations and to research the field of gene doping in order to develop methods of detection. To protect the health of athletes and to ensure equal competitive conditions, the International Olympic Committee, WADA and International Sports Federations have accepted performance-enhancing substances and methods as being doping, and have forbidden them. Nevertheless, the desire to win causes athletes to misuse these drugs and methods. This paper reviews the current status of gene doping and candidate performance enhancement genes, and also the use of gene therapy in sports medicine and ethics of genetic enhancement.

  4. Human Gene Therapy: Genes without Frontiers?

    Science.gov (United States)

    Simon, Eric J.

    2002-01-01

    Describes the latest advancements and setbacks in human gene therapy to provide reference material for biology teachers to use in their science classes. Focuses on basic concepts such as recombinant DNA technology, and provides examples of human gene therapy such as severe combined immunodeficiency syndrome, familial hypercholesterolemia, and…

  5. Gene network inference and biochemical assessment delineates GPCR pathways and CREB targets in small intestinal neuroendocrine neoplasia.

    Directory of Open Access Journals (Sweden)

    Ignat Drozdov

    Full Text Available Small intestinal (SI neuroendocrine tumors (NET are increasing in incidence, however little is known about their biology. High throughput techniques such as inference of gene regulatory networks from microarray experiments can objectively define signaling machinery in this disease. Genome-wide co-expression analysis was used to infer gene relevance network in SI-NETs. The network was confirmed to be non-random, scale-free, and highly modular. Functional analysis of gene co-expression modules revealed processes including 'Nervous system development', 'Immune response', and 'Cell-cycle'. Importantly, gene network topology and differential expression analysis identified over-expression of the GPCR signaling regulators, the cAMP synthetase, ADCY2, and the protein kinase A, PRKAR1A. Seven CREB response element (CRE transcripts associated with proliferation and secretion: BEX1, BICD1, CHGB, CPE, GABRB3, SCG2 and SCG3 as well as ADCY2 and PRKAR1A were measured in an independent SI dataset (n = 10 NETs; n = 8 normal preparations. All were up-regulated (p<0.035 with the exception of SCG3 which was not differently expressed. Forskolin (a direct cAMP activator, 10(-5 M significantly stimulated transcription of pCREB and 3/7 CREB targets, isoproterenol (a selective ß-adrenergic receptor agonist and cAMP activator, 10(-5 M stimulated pCREB and 4/7 targets while BIM-53061 (a dopamine D(2 and Serotonin [5-HT(2] receptor agonist, 10(-6 M stimulated 100% of targets as well as pCREB; CRE transcription correlated with the levels of cAMP accumulation and PKA activity; BIM-53061 stimulated the highest levels of cAMP and PKA (2.8-fold and 2.5-fold vs. 1.8-2-fold for isoproterenol and forskolin. Gene network inference and graph topology analysis in SI NETs suggests that SI NETs express neural GPCRs that activate different CRE targets associated with proliferation and secretion. In vitro studies, in a model NET cell system, confirmed that transcriptional

  6. Genes and Hearing Loss

    Science.gov (United States)

    ... Find an ENT Doctor Near You Genes and Hearing Loss Genes and Hearing Loss Patient Health Information News media interested in covering ... One of the most common birth defects is hearing loss or deafness (congenital), which can affect as many ...

  7. Essential Bacillus subtilis genes

    DEFF Research Database (Denmark)

    Kobayashi, K.; Ehrlich, S.D.; Albertini, A.

    2003-01-01

    To estimate the minimal gene set required to sustain bacterial life in nutritious conditions, we carried out a systematic inactivation of Bacillus subtilis genes. Among approximate to4,100 genes of the organism, only 192 were shown to be indispensable by this or previous work. Another 79 genes were...... predicted to be essential. The vast majority of essential genes were categorized in relatively few domains of cell metabolism, with about half involved in information processing, one-fifth involved in the synthesis of cell envelope and the determination of cell shape and division, and one-tenth related...... to cell energetics. Only 4% of essential genes encode unknown functions. Most essential genes are present throughout a wide range of Bacteria, and almost 70% can also be found in Archaea and Eucarya. However, essential genes related to cell envelope, shape, division, and respiration tend to be lost from...

  8. Cochlear Gene Therapy

    OpenAIRE

    2012-01-01

    The purpose of this review is to highlight recent advances in cochlear gene therapy over the past several years. Cochlear gene therapy has undergone tremendous advances over the past decade. Beginning with some groundbreaking work in 2005 documenting hair cell regeneration using virallymediated delivery of the mouse atonal 1 gene, gene therapy is now being explored as a possible treatment for a variety of causes of hearing loss.

  9. Discovering genes underlying QTL

    Energy Technology Data Exchange (ETDEWEB)

    Vanavichit, Apichart [Kasetsart University, Kamphaengsaen, Nakorn Pathom (Thailand)

    2002-02-01

    A map-based approach has allowed scientists to discover few genes at a time. In addition, the reproductive barrier between cultivated rice and wild relatives has prevented us from utilizing the germ plasm by a map-based approach. Most genetic traits important to agriculture or human diseases are manifested as observable, quantitative phenotypes called Quantitative Trait Loci (QTL). In many instances, the complexity of the phenotype/genotype interaction and the general lack of clearly identifiable gene products render the direct molecular cloning approach ineffective, thus additional strategies like genome mapping are required to identify the QTL in question. Genome mapping requires no prior knowledge of the gene function, but utilizes statistical methods to identify the most likely gene location. To completely characterize genes of interest, the initially mapped region of a gene location will have to be narrowed down to a size that is suitable for cloning and sequencing. Strategies for gene identification within the critical region have to be applied after the sequencing of a potentially large clone or set of clones that contains this gene(s). Tremendous success of positional cloning has been shown for cloning many genes responsible for human diseases, including cystic fibrosis and muscular dystrophy as well as plant disease resistance genes. Genome and QTL mapping, positional cloning: the pre-genomics era, comparative approaches to gene identification, and positional cloning: the genomics era are discussed in the report. (M. Suetake)

  10. Reading and Generalist Genes

    Science.gov (United States)

    Haworth, Claire M. A.; Meaburn, Emma L.; Harlaar, Nicole; Plomin, Robert

    2007-01-01

    Twin-study research suggests that many (but not all) of the same genes contribute to genetic influence on diverse learning abilities and disabilities, a hypothesis called "generalist genes". This generalist genes hypothesis was tested using a set of 10 DNA markers (single nucleotide polymorphisms [SNPs]) found to be associated with early reading…

  11. Journey from Jumping Genes to Gene Therapy.

    Science.gov (United States)

    Whartenby, Katharine A

    2015-01-01

    Gene therapy for cancer is a still evolving approach that resulted from a long history of studies into genetic modification of organisms. The fascination with manipulating gene products has spanned hundreds if not thousands of years, beginning with observations of the hereditary nature of traits in plants and culminating to date in the alteration of genetic makeup in humans via modern technology. From early discoveries noting the potential for natural mobility of genetic material to the culmination of clinical trials in a variety of disease, gene transfer has had an eventful and sometimes tumultuous course. Within the present review is a brief history of the biology of gene transfer, how it came to be applied to genetic diseases, and its early applications to cancer therapies. Some of the different types of methods used to modify cells, the theories behind the approaches, and some of the limitations encountered along the way are reviewed.

  12. Gene conversion in human rearranged immunoglobulin genes.

    Science.gov (United States)

    Darlow, John M; Stott, David I

    2006-07-01

    Over the past 20 years, many DNA sequences have been published suggesting that all or part of the V(H) segment of a rearranged immunoglobulin gene may be replaced in vivo. Two different mechanisms appear to be operating. One of these is very similar to primary V(D)J recombination, involving the RAG proteins acting upon recombination signal sequences, and this has recently been proven to occur. Other sequences, many of which show partial V(H) replacements with no addition of untemplated nucleotides at the V(H)-V(H) joint, have been proposed to occur by an unusual RAG-mediated recombination with the formation of hybrid (coding-to-signal) joints. These appear to occur in cells already undergoing somatic hypermutation in which, some authors are convinced, RAG genes are silenced. We recently proposed that the latter type of V(H) replacement might occur by homologous recombination initiated by the activity of AID (activation-induced cytidine deaminase), which is essential for somatic hypermutation and gene conversion. The latter has been observed in other species, but not in human Ig genes, so far. In this paper, we present a new analysis of sequences published as examples of the second type of rearrangement. This not only shows that AID recognition motifs occur in recombination regions but also that some sequences show replacement of central sections by a sequence from another gene, similar to gene conversion in the immunoglobulin genes of other species. These observations support the proposal that this type of rearrangement is likely to be AID-mediated rather than RAG-mediated and is consistent with gene conversion.

  13. Gene therapy in periodontics

    Directory of Open Access Journals (Sweden)

    Anirban Chatterjee

    2013-01-01

    Full Text Available GENES are made of DNA - the code of life. They are made up of two types of base pair from different number of hydrogen bonds AT, GC which can be turned into instruction. Everyone inherits genes from their parents and passes them on in turn to their children. Every person′s genes are different, and the changes in sequence determine the inherited differences between each of us. Some changes, usually in a single gene, may cause serious diseases. Gene therapy is ′the use of genes as medicine′. It involves the transfer of a therapeutic or working gene copy into specific cells of an individual in order to repair a faulty gene copy. Thus it may be used to replace a faulty gene, or to introduce a new gene whose function is to cure or to favorably modify the clinical course of a condition. It has a promising era in the field of periodontics. Gene therapy has been used as a mode of tissue engineering in periodontics. The tissue engineering approach reconstructs the natural target tissue by combining four elements namely: Scaffold, signaling molecules, cells and blood supply and thus can help in the reconstruction of damaged periodontium including cementum, gingival, periodontal ligament and bone.

  14. Regulated Gene Therapy.

    Science.gov (United States)

    Breger, Ludivine; Wettergren, Erika Elgstrand; Quintino, Luis; Lundberg, Cecilia

    2016-01-01

    Gene therapy represents a promising approach for the treatment of monogenic and multifactorial neurological disorders. It can be used to replace a missing gene and mutated gene or downregulate a causal gene. Despite the versatility of gene therapy, one of the main limitations lies in the irreversibility of the process: once delivered to target cells, the gene of interest is constitutively expressed and cannot be removed. Therefore, efficient, safe and long-term gene modification requires a system allowing fine control of transgene expression.Different systems have been developed over the past decades to regulate transgene expression after in vivo delivery, either at transcriptional or post-translational levels. The purpose of this chapter is to give an overview on current regulatory system used in the context of gene therapy for neurological disorders. Systems using external regulation of transgenes using antibiotics are commonly used to control either gene expression using tetracycline-controlled transcription or protein levels using destabilizing domain technology. Alternatively, specific promoters of genes that are regulated by disease mechanisms, increasing expression as the disease progresses or decreasing expression as disease regresses, are also examined. Overall, this chapter discusses advantages and drawbacks of current molecular methods for regulated gene therapy in the central nervous system.

  15. Gene therapy: An overview

    Directory of Open Access Journals (Sweden)

    Sudip Indu

    2013-01-01

    Full Text Available Gene therapy "the use of genes as medicine" involves the transfer of a therapeutic or working copy of a gene into specific cells of an individual in order to repair a faulty gene copy. The technique may be used to replace a faulty gene, or to introduce a new gene whose function is to cure or to favorably modify the clinical course of a condition. The objective of gene therapy is to introduce new genetic material into target cells while causing no damage to the surrounding healthy cells and tissues, hence the treatment related morbidity is decreased. The delivery system includes a vector that delivers a therapeutic gene into the patient′s target cell. Functional proteins are created from the therapeutic gene causing the cell to return to a normal stage. The vectors used in gene therapy can be viral and non-viral. Gene therapy, an emerging field of biomedicine, is still at infancy and much research remains to be done before this approach to the treatment of condition will realize its full potential.

  16. Gene therapy in periodontics.

    Science.gov (United States)

    Chatterjee, Anirban; Singh, Nidhi; Saluja, Mini

    2013-03-01

    GENES are made of DNA - the code of life. They are made up of two types of base pair from different number of hydrogen bonds AT, GC which can be turned into instruction. Everyone inherits genes from their parents and passes them on in turn to their children. Every person's genes are different, and the changes in sequence determine the inherited differences between each of us. Some changes, usually in a single gene, may cause serious diseases. Gene therapy is 'the use of genes as medicine'. It involves the transfer of a therapeutic or working gene copy into specific cells of an individual in order to repair a faulty gene copy. Thus it may be used to replace a faulty gene, or to introduce a new gene whose function is to cure or to favorably modify the clinical course of a condition. It has a promising era in the field of periodontics. Gene therapy has been used as a mode of tissue engineering in periodontics. The tissue engineering approach reconstructs the natural target tissue by combining four elements namely: Scaffold, signaling molecules, cells and blood supply and thus can help in the reconstruction of damaged periodontium including cementum, gingival, periodontal ligament and bone.

  17. Cyanobacterial signature genes.

    Science.gov (United States)

    Martin, Kirt A; Siefert, Janet L; Yerrapragada, Sailaja; Lu, Yue; McNeill, Thomas Z; Moreno, Pedro A; Weinstock, George M; Widger, William R; Fox, George E

    2003-01-01

    A comparison of 8 cyanobacterial genomes reveals that there are 181 shared genes that do not have obvious orthologs in other bacteria. These signature genes define aspects of the genotype that are uniquely cyanobacterial. Approximately 25% of these genes have been associated with some function. These signature genes may or may not be involved in photosynthesis but likely they will be in many cases. In addition, several examples of widely conserved gene order involving two or more signature genes were observed. This suggests there may be regulatory processes that have been preserved throughout the long history of the cyanobacterial phenotype. The results presented here will be especially useful because they identify which of the many genes of unassigned function are likely to be of the greatest interest.

  18. Sensitivity of Listeria monocytogenes to sanitizers used in the meat processing industry.

    Science.gov (United States)

    Romanova, Nadya; Favrin, Stacy; Griffiths, Mansel W

    2002-12-01

    Nineteen Listeria monocytogenes strains were characterized by automated ribotyping, pulsed-field gel electrophoresis, and plasmid profiling to determine the relationship between genotype and sanitizer resistance. Isolates within a ribogroup had a consistent sensitivity or resistance phenotype except for ribogroup C isolates. All isolates with resistance phenotypes harbored two plasmids. The sensitivity of L. monocytogenes strains to quaternary ammonium compounds (QACs) was correlated with sensitivity to sanitizers and antibiotics with other modes of action. All isolates tested contained the mdrL gene, which encodes an efflux pump that confers resistance to QACs and is both chromosome and plasmid borne.

  19. Two paediatric cases of skin and soft-tissue infections due to clindamycin-resistant Staphylococcus aureus carrying a plasmid-encoded vga(A) allelic variant for a putative efflux pump.

    Science.gov (United States)

    Qin, Xuan; Poon, Brian; Kwong, Justin; Niles, Denver; Schmidt, Byron Z; Rajagopal, Lakshmi; Gantt, Soren

    2011-07-01

    Two clinical Staphylococcus aureus isolates were investigated due to their unusual antimicrobial susceptibility pattern, i.e. erythromycin-susceptible but clindamycin-resistant. These isolates harboured identical copies of a plasmid-borne vga(A)(LC) gene not previously described in S. aureus. The native plasmids carrying vga(A)(LC) were transferable to a susceptible laboratory strain of S. aureus in vitro, in which they conferred resistance patterns similar to the parent isolates. Copyright © 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  20. Characterization of the flagellar biosynthesis regulatory geneflbD in Azospirillum brasilense

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A flagellar gene cluster fragment includingflbD of Azospirillum brasilense was cloned and sequenced, The flbD mutant strain was found to be nonmotile-losing both polar and lateral flagella (Fla-Laf-), Motility and flagella were regained by complementation with plasmid-borne multicopy flbD, but altered with larger swarming circle and fewer lateral flagella on the semisolid plate, This result indicated that FIbD plays an important role in the regulation of both polar and lateral flagellar biosynthesis in A.brasilense.

  1. Primetime for Learning Genes

    Science.gov (United States)

    Keifer, Joyce

    2017-01-01

    Learning genes in mature neurons are uniquely suited to respond rapidly to specific environmental stimuli. Expression of individual learning genes, therefore, requires regulatory mechanisms that have the flexibility to respond with transcriptional activation or repression to select appropriate physiological and behavioral responses. Among the mechanisms that equip genes to respond adaptively are bivalent domains. These are specific histone modifications localized to gene promoters that are characteristic of both gene activation and repression, and have been studied primarily for developmental genes in embryonic stem cells. In this review, studies of the epigenetic regulation of learning genes in neurons, particularly the brain-derived neurotrophic factor gene (BDNF), by methylation/demethylation and chromatin modifications in the context of learning and memory will be highlighted. Because of the unique function of learning genes in the mature brain, it is proposed that bivalent domains are a characteristic feature of the chromatin landscape surrounding their promoters. This allows them to be “poised” for rapid response to activate or repress gene expression depending on environmental stimuli. PMID:28208656

  2. Primetime for Learning Genes.

    Science.gov (United States)

    Keifer, Joyce

    2017-02-11

    Learning genes in mature neurons are uniquely suited to respond rapidly to specific environmental stimuli. Expression of individual learning genes, therefore, requires regulatory mechanisms that have the flexibility to respond with transcriptional activation or repression to select appropriate physiological and behavioral responses. Among the mechanisms that equip genes to respond adaptively are bivalent domains. These are specific histone modifications localized to gene promoters that are characteristic of both gene activation and repression, and have been studied primarily for developmental genes in embryonic stem cells. In this review, studies of the epigenetic regulation of learning genes in neurons, particularly the brain-derived neurotrophic factor gene (BDNF), by methylation/demethylation and chromatin modifications in the context of learning and memory will be highlighted. Because of the unique function of learning genes in the mature brain, it is proposed that bivalent domains are a characteristic feature of the chromatin landscape surrounding their promoters. This allows them to be "poised" for rapid response to activate or repress gene expression depending on environmental stimuli.

  3. An Ontology of Gene

    OpenAIRE

    Masuya, Hiroshi; Mizoguchi, Riichiro

    2012-01-01

    The concept of a gene was established in the era of classical genetics and is now essential for life science for elucidating the molecular basis of the coding of genetic information necessary to realize the body of an organism and its biological functions. However, an ontology fully representing multiple aspects of a gene is still not available. In this study, we dissected the biological and ontological definitions of bearers of genetic information, including genes and alleles. Based on this ...

  4. Placental gene therapy

    OpenAIRE

    David, A. L.; Ashcroft, R

    2009-01-01

    Gene therapy uses genetic material as a drug delivery vehicle to express therapeutic proteins. Placental gene therapy may be useful for correction of two important obstetric conditions, foetal growth restriction and pre-eclampsia in which there is a failure of the physiological trophoblast remodelling of the uterine spiral arteries in early pregnancy. The patient in this scenario is the foetus. Placental gene therapy might be justifiable when: there is reasonable certainty that the foetus wil...

  5. Complex integrons containing qnrB4-ampC (bla(DHA-1)) in plasmids of multidrug-resistant Citrobacter freundii from wastewater.

    Science.gov (United States)

    Yim, Grace; Kwong, Waldan; Davies, Julian; Miao, Vivian

    2013-02-01

    Microbial populations in wastewater treatment plants (WWTPs) are increasingly being recognized as environmental reservoirs of antibiotic resistance genes. PCR amplicons for plasmid-mediated quinolone resistance determinants qnrA, qnrB, and qnrS were recorded in samples from a WWTP in Vancouver, British Columbia. Six strains of ciprofloxacin-resistant Citrobacter freundii were isolated and found to carry mutations in gyrA and parC, as well as multiple plasmid-borne resistance genes, collectively including qnrB; aac(6')-Ib-cr; β-lactamase-encoding genes from molecular classes A (blaTEM-1), C (ampC), D (blaOXA-1, blaOXA-10); and genes for resistance to 5 other types of antibiotics. In 3 strains, large (>60 kb) plasmids carried qnrB4 and ampC as part of a complex integron in a 14 kb arrangement that has been reported worldwide but, until recently, only among pathogenic strains of Klebsiella. Analysis of single-nucleotide polymorphisms in the qnrB4-ampC regions infers 2 introductions into the WWTP environment. These results suggest recent passage of plasmid-borne fluoroquinolone and β-lactam resistance genes from pathogens to bacteria that may be indigenous inhabitants of WWTPs, thus contributing to an environmental pool of antibiotic resistance.

  6. Antisense gene silencing

    DEFF Research Database (Denmark)

    Nielsen, Troels T; Nielsen, Jørgen E

    2013-01-01

    Since the first reports that double-stranded RNAs can efficiently silence gene expression in C. elegans, the technology of RNA interference (RNAi) has been intensively exploited as an experimental tool to study gene function. With the subsequent discovery that RNAi could also be applied to mammal......Since the first reports that double-stranded RNAs can efficiently silence gene expression in C. elegans, the technology of RNA interference (RNAi) has been intensively exploited as an experimental tool to study gene function. With the subsequent discovery that RNAi could also be applied...

  7. History of gene therapy.

    Science.gov (United States)

    Wirth, Thomas; Parker, Nigel; Ylä-Herttuala, Seppo

    2013-08-10

    Two decades after the initial gene therapy trials and more than 1700 approved clinical trials worldwide we not only have gained much new information and knowledge regarding gene therapy in general, but also learned to understand the concern that has persisted in society. Despite the setbacks gene therapy has faced, success stories have increasingly emerged. Examples for these are the positive recommendation for a gene therapy product (Glybera) by the EMA for approval in the European Union and the positive trials for the treatment of ADA deficiency, SCID-X1 and adrenoleukodystrophy. Nevertheless, our knowledge continues to grow and during the course of time more safety data has become available that helps us to develop better gene therapy approaches. Also, with the increased understanding of molecular medicine, we have been able to develop more specific and efficient gene transfer vectors which are now producing clinical results. In this review, we will take a historical view and highlight some of the milestones that had an important impact on the development of gene therapy. We will also discuss briefly the safety and ethical aspects of gene therapy and address some concerns that have been connected with gene therapy as an important therapeutic modality.

  8. Using CPE Function to Size Capacitor Storage for Electric Vehicles and Quantifying Battery Degradation during Different Driving Cycles

    OpenAIRE

    Cong Zhang; Haitao Min; Yuanbin Yu; Dai Wang; Justin Luke; Daniel Opila; Samveg Saxena

    2016-01-01

    Range anxiety and battery cycle life are two major factors which restrict the development of electric vehicles. Battery degradation can be reduced by adding supercapacitors to create a Hybrid Energy Storage System. This paper proposes a systematic approach to configure the hybrid energy storage system and quantifies the battery degradation for electric vehicles when using supercapacitors. A continuous power-energy function is proposed to establish supercapacitor size based on national househo...

  9. Using CPE Function to Size Capacitor Storage for Electric Vehicles and Quantifying Battery Degradation during Different Driving Cycles

    Directory of Open Access Journals (Sweden)

    Cong Zhang

    2016-11-01

    Full Text Available Range anxiety and battery cycle life are two major factors which restrict the development of electric vehicles. Battery degradation can be reduced by adding supercapacitors to create a Hybrid Energy Storage System. This paper proposes a systematic approach to configure the hybrid energy storage system and quantifies the battery degradation for electric vehicles when using supercapacitors. A continuous power-energy function is proposed to establish supercapacitor size based on national household travel survey statistics. By analyzing continuous driving action in standard driving cycles and special driving phases (start up and acceleration, the supercapacitor size is calculated to provide a compromise between the capacitor size and battery degradation. Estimating the battery degradation after 10 years, the battery capacity loss value decreases 17.55% and 21.6%, respectively, under the urban dynamometer driving schedule and the US06. Furthermore, the battery lifespan of the continuous power-energy configured system is prolonged 28.62% and 31.39%, respectively, compared with the battery alone system.

  10. Using CPE Function to Size Capacitor Storage for Electric Vehicles and Quantifying Battery Degradation during Different Driving Cycles

    OpenAIRE

    Cong Zhang; Haitao Min; Yuanbin Yu; Dai Wang; Justin Luke; Daniel Opila; Samveg Saxena

    2016-01-01

    Range anxiety and battery cycle life are two major factors which restrict the development of electric vehicles. Battery degradation can be reduced by adding supercapacitors to create a Hybrid Energy Storage System. This paper proposes a systematic approach to configure the hybrid energy storage system and quantifies the battery degradation for electric vehicles when using supercapacitors. A continuous power-energy function is proposed to establish supercapacitor size based on national househo...

  11. Delivery Systems in Gene Therapy

    Institute of Scientific and Technical Information of China (English)

    Liu Hu; Anas El-Aneed; Cui Guohui

    2005-01-01

    1 Gene therapy Gene therapy includes the treatment of both genetically based and infectious diseases by introducing genetic materials which have therapeutic effects[1~3]. In its simplest terms, a wild type gene (which is non-functional in the cell leading to disease development) is introduced into the somatic cell lacking this gene to restore the normal gene function in this cell. Many gene therapy strategies, however, utilize genes to destroy specific cells.

  12. Gene promoters dictate histone occupancy within genes.

    Science.gov (United States)

    Perales, Roberto; Erickson, Benjamin; Zhang, Lian; Kim, Hyunmin; Valiquett, Elan; Bentley, David

    2013-10-01

    Spt6 is a transcriptional elongation factor and histone chaperone that reassembles transcribed chromatin. Genome-wide H3 mapping showed that Spt6 preferentially maintains nucleosomes within the first 500 bases of genes and helps define nucleosome-depleted regions in 5' and 3' flanking sequences. In Spt6-depleted cells, H3 loss at 5' ends correlates with reduced pol II density suggesting enhanced transcription elongation. Consistent with its 'Suppressor of Ty' (Spt) phenotype, Spt6 inactivation caused localized H3 eviction over 1-2 nucleosomes at 5' ends of Ty elements. H3 displacement differed between genes driven by promoters with 'open'/DPN and 'closed'/OPN chromatin conformations with similar pol II densities. More eviction occurred on genes with 'closed' promoters, associated with 'noisy' transcription. Moreover, swapping of 'open' and 'closed' promoters showed that they can specify distinct downstream patterns of histone eviction/deposition. These observations suggest a novel function for promoters in dictating histone dynamics within genes possibly through effects on transcriptional bursting or elongation rate.

  13. Smart Genes, Stupid Science.

    Science.gov (United States)

    Randerson, Sherman; Mahadeva, Madhu N.

    1983-01-01

    Because many people still believe that specific, identifiable genes dictate the level of human intelligence and that the number/quality of these genes can be evaluated, presents evidence from human genetics (related to nervous system development) to counter this view. Also disputes erroneous assumptions made in "heritability studies" of human…

  14. XLMR genes: update 2000.

    NARCIS (Netherlands)

    Chiurazzi, P.; Hamel, B.C.J.; Neri, G.

    2001-01-01

    This is the sixth edition of the catalogue of XLMR genes, ie X-linked genes whose malfunctioning causes mental retardation. The cloning era is not yet concluded, actually much remains to be done to account for the 202 XLMR conditions listed in this update. Many of these may eventually prove to be du

  15. Glaucoma Genes and Mechanisms.

    Science.gov (United States)

    Wiggs, Janey L

    2015-01-01

    Genetic studies have yielded important genes contributing to both early-onset and adult-onset forms of glaucoma. The proteins encoded by the current collection of glaucoma genes participate in a broad range of cellular processes and biological systems. Approximately half the glaucoma-related genes function in the extracellular matrix, however proteins involved in cytokine signaling, lipid metabolism, membrane biology, regulation of cell division, autophagy, and ocular development also contribute to the disease pathogenesis. While the function of these proteins in health and disease are not completely understood, recent studies are providing insight into underlying disease mechanisms, a critical step toward the development of gene-based therapies. In this review, genes known to cause early-onset glaucoma or contribute to adult-onset glaucoma are organized according to the cell processes or biological systems that are impacted by the function of the disease-related protein product.

  16. Gene therapy for hemophilia.

    Science.gov (United States)

    Chuah, M K; Evens, H; VandenDriessche, T

    2013-06-01

    Hemophilia A and B are X-linked monogenic disorders resulting from deficiencies of factor VIII and FIX, respectively. Purified clotting factor concentrates are currently intravenously administered to treat hemophilia, but this treatment is non-curative. Therefore, gene-based therapies for hemophilia have been developed to achieve sustained high levels of clotting factor expression to correct the clinical phenotype. Over the past two decades, different types of viral and non-viral gene delivery systems have been explored for hemophilia gene therapy research with a variety of target cells, particularly hepatocytes, hematopoietic stem cells, skeletal muscle cells, and endothelial cells. Lentiviral and adeno-associated virus (AAV)-based vectors are among the most promising vectors for hemophilia gene therapy. In preclinical hemophilia A and B animal models, the bleeding phenotype was corrected with these vectors. Some of these promising preclinical results prompted clinical translation to patients suffering from a severe hemophilic phenotype. These patients receiving gene therapy with AAV vectors showed long-term expression of therapeutic FIX levels, which is a major step forwards in this field. Nevertheless, the levels were insufficient to prevent trauma or injury-induced bleeding episodes. Another challenge that remains is the possible immune destruction of gene-modified cells by effector T cells, which are directed against the AAV vector antigens. It is therefore important to continuously improve the current gene therapy approaches to ultimately establish a real cure for hemophilia. © 2013 International Society on Thrombosis and Haemostasis.

  17. Gene amplification in carcinogenesis

    Directory of Open Access Journals (Sweden)

    Lucimari Bizari

    2006-01-01

    Full Text Available Gene amplification increases the number of genes in a genome and can give rise to karyotype abnormalities called double minutes (DM and homogeneously staining regions (HSR, both of which have been widely observed in human tumors but are also known to play a major role during embryonic development due to the fact that they are responsible for the programmed increase of gene expression. The etiology of gene amplification during carcinogenesis is not yet completely understood but can be considered a result of genetic instability. Gene amplification leads to an increase in protein expression and provides a selective advantage during cell growth. Oncogenes such as CCND1, c-MET, c-MYC, ERBB2, EGFR and MDM2 are amplified in human tumors and can be associated with increased expression of their respective proteins or not. In general, gene amplification is associated with more aggressive tumors, metastases, resistance to chemotherapy and a decrease in the period during which the patient stays free of the disease. This review discusses the major role of gene amplification in the progression of carcinomas, formation of genetic markers and as possible therapeutic targets for the development of drugs for the treatment of some types of tumors.

  18. Analysis of HPV-16 early gene regulationin cellular differentiation, includingcharacterisation of the possiblerole of CPEB proteins

    DEFF Research Database (Denmark)

    Hansen, Christina Neigaard

    cytoplasmic polyadenylation elements (CPEs) situated in the distal part of the messengers. These CPE sequences bind the CPE-binding protein CPEB. In this study, the mRNA levels of the 4 CPEBs in primary keratinocytes, in 8 different cell lines, and in both normal and cancer genital tissues have been analysed....... Huge variations among both the different cell types and the 4 CPEBs were observed. Interestingly, in ovarian cancer we found downregulated mRNA levels of CPEB1, a protein that previously has been suggested to be a tumor suppressor protein. We also found a tendency for the CPEB3 mRNA to be downregulated...... E6/E7 expression. HPV-16 preferably infects the proliferating cells of the continually renewing stratified epithelium lining the genital tract. These proliferating cells will differentiate as they are pushed upwards in the epithelium by newly produced daughter cells. The virus life cycle is tightly...

  19. Antisense gene silencing

    DEFF Research Database (Denmark)

    Nielsen, Troels T; Nielsen, Jørgen E

    2013-01-01

    Since the first reports that double-stranded RNAs can efficiently silence gene expression in C. elegans, the technology of RNA interference (RNAi) has been intensively exploited as an experimental tool to study gene function. With the subsequent discovery that RNAi could also be applied...... to mammalian cells, the technology of RNAi expanded from being a valuable experimental tool to being an applicable method for gene-specific therapeutic regulation, and much effort has been put into further refinement of the technique. This review will focus on how RNAi has developed over the years and how...

  20. Gene Therapy of Cancerous Diseases

    OpenAIRE

    Valenčáková, A.; Dziaková, A.; Hatalová, E.

    2015-01-01

    Gene therapy of cancerous diseases provides new means of curing patients with oncologic illnesses. There are several approaches in treating cancer by gene therapy. Most commonly used methods are: cancer immunogene therapy, suicide gene therapy, application of tumor-suppressor genes, antiangiogenic therapy, mesenchymal stem cells used as vectors, gene directed enzyme/prodrug therapy and bacteria used as anti-cancer agents. Cancer gene immunotherapy uses several immunologic agents for the purp...

  1. "Bad genes" & criminal responsibility.

    Science.gov (United States)

    González-Tapia, María Isabel; Obsuth, Ingrid

    2015-01-01

    The genetics of the accused is trying to break into the courts. To date several candidate genes have been put forward and their links to antisocial behavior have been examined and documented with some consistency. In this paper, we focus on the so called "warrior gene", or the low-activity allele of the MAOA gene, which has been most consistently related to human behavior and specifically to violence and antisocial behavior. In preparing this paper we had two objectives. First, to summarize and analyze the current scientific evidence, in order to gain an in depth understanding of the state of the issue and determine whether a dominant line of generally accepted scientific knowledge in this field can be asserted. Second, to derive conclusions and put forward recommendations related to the use of genetic information, specifically the presence of the low-activity genotype of the MAOA gene, in modulation of criminal responsibility in European and US courts.

  2. Gene Expression Omnibus (GEO)

    Data.gov (United States)

    U.S. Department of Health & Human Services — Gene Expression Omnibus is a public functional genomics data repository supporting MIAME-compliant submissions of array- and sequence-based data. Tools are provided...

  3. Gene therapy in ophthalmology.

    Science.gov (United States)

    Uthra, Satagopan; Kumaramanickavel, Govindasamy

    2009-09-01

    It has been more than a year since ophthalmologists and scientists under Dr. Robin Ali's team at the Moorsfield Eye Hospital and the Institute of Ophthalmology, University College London, successfully treated patients with a severely blinding disease, Leber's congenital amaurosis (LCA) using gene therapy. This success does not look to be transient, and this achievement in gene replacement therapy clinical trial for LCA has instilled hope in numerous families with patients suffering from this and similar retinal degenerative diseases, for whom restoration of lost vision has remained a distant dream so far. The encouragement that this success has given is expected to also lead to start of clinical trials for other blinding ocular diseases for which gene therapy experiments at the laboratory and animal levels have been successful. This article reviews the various studies that have led to the understanding of gene therapy outcomes in human ocular diseases and attempts to provide a brief sketch of successful clinical trials.

  4. Gene therapy for hemophilia.

    Science.gov (United States)

    Hortelano, G; Chang, P L

    2000-01-01

    Hemophilia A and B are X-linked genetic disorders caused by deficiency of the coagulation factors VIII and IX, respectively. Because of the health hazards and costs of current product replacement therapy, much effort is devoted to the development of gene therapy for these disorders. Approaches to gene therapy for the hemophilias include: ex vivo gene therapy in which cells from the intended recipients are explanted, genetically modified to secrete Factor VIII or IX, and reimplanted into the donor; in vivo gene therapy in which Factor VIII or IX encoding vectors are directly injected into the recipient; and non-autologous gene therapy in which universal cell lines engineered to secrete Factor VIII or IX are enclosed in immuno-protective devices before implantation into recipients. Research into these approaches is aided by the many murine and canine models available. While problems of achieving high and sustained levels of factor delivery, and issues related to efficacy, safety and cost are still to be resolved, progress in gene therapy for the hemophilias has been encouraging and is likely to reach human clinical trial in the foreseeable future.

  5. Evidence for homosexuality gene

    Energy Technology Data Exchange (ETDEWEB)

    Pool, R.

    1993-07-16

    A genetic analysis of 40 pairs of homosexual brothers has uncovered a region on the X chromosome that appears to contain a gene or genes for homosexuality. When analyzing the pedigrees of homosexual males, the researcheres found evidence that the trait has a higher likelihood of being passed through maternal genes. This led them to search the X chromosome for genes predisposing to homosexuality. The researchers examined the X chromosomes of pairs of homosexual brothers for regions of DNA that most or all had in common. Of the 40 sets of brothers, 33 shared a set of five markers in the q28 region of the long arm of the X chromosome. The linkage has a LOD score of 4.0, which translates into a 99.5% certainty that there is a gene or genes in this area that predispose males to homosexuality. The chief researcher warns, however, that this one site cannot explain all instances of homosexuality, since there were some cases where the trait seemed to be passed paternally. And even among those brothers where there was no evidence that the trait was passed paternally, seven sets of brothers did not share the Xq28 markers. It seems likely that homosexuality arises from a variety of causes.

  6. Gene-gene, gene-environment, gene-nutrient interactionsand single nucleotide polymorphisms of inflammatorycytokines

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Inflammation plays a significant role in the etiologyof type 2 diabetes mellitus (T2DM). The rise in thepro-inflammatory cytokines is the essential step inglucotoxicity and lipotoxicity induced mitochondrialinjury, oxidative stress and beta cell apoptosis inT2DM. Among the recognized markers are interleukin(IL)-6, IL-1, IL-10, IL-18, tissue necrosis factor-alpha(TNF-α), C-reactive protein, resistin, adiponectin, tissueplasminogen activator, fibrinogen and heptoglobins.Diabetes mellitus has firm genetic and very strongenvironmental influence; exhibiting a polygenic modeof inheritance. Many single nucleotide polymorphisms(SNPs) in various genes including those of pro and antiinflammatorycytokines have been reported as a riskfor T2DM. Not all the SNPs have been confirmed byunifying results in different studies and wide variationshave been reported in various ethnic groups. Theinter-ethnic variations can be explained by the factthat gene expression may be regulated by gene-gene,gene-environment and gene-nutrient interactions. Thisreview highlights the impact of these interactions ondetermining the role of single nucleotide polymorphismof IL-6, TNF-α, resistin and adiponectin in pathogenesisof T2DM.

  7. Identification of four soybean reference genes for gene expression normalization

    Science.gov (United States)

    Gene expression analysis requires the use of reference genes stably expressed independently of specific tissues or environmental conditions. Housekeeping genes (e.g., actin, tubulin, ribosomal, polyubiquitin and elongation factor 1-alpha) are commonly used as reference genes with the assumption tha...

  8. The Mycoplasma hominis vaa gene displays a mosaic gene structure

    DEFF Research Database (Denmark)

    Boesen, Thomas; Emmersen, Jeppe M. G.; Jensen, Lise T.;

    1998-01-01

    Mycoplasma hominis contains a variable adherence-associated (vaa) gene. To classify variants of the vaa genes, we examined 42 M. hominis isolated by PCR, DNA sequencing and immunoblotting. This uncovered the existence of five gene categories. Comparison of the gene types revealed a modular compos...

  9. Hox genes and study of Hox genes in crustacean

    Institute of Scientific and Technical Information of China (English)

    HOU Lin; CHEN Zhijuan; XU Mingyu; LIN Shengguo; WANG Lu

    2004-01-01

    Homeobox genes have been discovered in many species. These genes are known to play a major role in specifying regional identity along the anterior-posterior axis of animals from a wide range of phyla.The products of the homeotic genes are a set of evolutionarily conserved transcription factors that control elaborate developmental processes and specify cell fates in metazoans. Crustacean, presenting a variety of body plans not encountered in any other class or phylum of the Metazoa, has been shown to possess a single set of homologous Hox genes like insect. The ancestral crustacean Hox gene complex comprised ten genes: eight homologous to the hometic Hox genes and two related to nonhomeotic genes presented within the insect Hox complexes. The crustacean in particular exhibits an abundant diversity segment specialization and tagmosis. This morphological diversity relates to the Hox genes. In crustacean body plan, different Hox genes control different segments and tagmosis.

  10. Entrez Gene: gene-centered information at NCBI

    OpenAIRE

    Maglott, Donna; Ostell, Jim; Pruitt, Kim D; Tatusova, Tatiana

    2006-01-01

    Entrez Gene () is NCBI's database for gene-specific information. Entrez Gene includes records from genomes that have been completely sequenced, that have an active research community to contribute gene-specific information or that are scheduled for intense sequence analysis. The content of Entrez Gene represents the result of both curation and automated integration of data from NCBI's Reference Sequence project (RefSeq), from collaborating model organism databases and from other databases wit...

  11. Gene therapy for brain tumors.

    Science.gov (United States)

    Bansal, K; Engelhard, H H

    2000-09-01

    "Gene therapy" can be defined as the transfer of genetic material into a patient's cells for therapeutic purposes. To date, a diverse and creative assortment of treatment strategies utilizing gene therapy have been devised, including gene transfer for modulating the immune system, enzyme prodrug ("suicide gene") therapy, oncolytic therapy, replacement/therapeutic gene transfer, and antisense therapy. For malignant glioma, gene-directed prodrug therapy using the herpes simplex virus thymidine kinase gene was the first gene therapy attempted clinically. A variety of different strategies have now been pursued experimentally and in clinical trials. Although, to date, gene therapy for brain tumors has been found to be reasonably safe, concerns still exist regarding issues related to viral delivery, transduction efficiency, potential pathologic response of the brain, and treatment efficacy. Improved viral vectors are being sought, and potential use of gene therapy in combination with other treatments is being investigated.

  12. Introns in higher plant genes

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The intron is an important component of eukaryotic gene. Extensive studies have been conducted to get a better understanding of its structure and function. This paper presents a brief review of the structure and function of introns in higher plant genes. It is shown that higher plant introns possess structural properties shared by all eukaryotic introns, however, they also exhibit a striking degree of diversity. The process of intron splicing in higher plant genes involves interaction between multiple cis-acting elements and trans-acting factors, such as 5′ splicing site, 3′ splicing site and many protein factors. The process of intron splicing is an important level at which gene expression is regulated. Especially alternative splicing of intron can regulate time and space of gene expression. In addition, some introns in higher plant genes also regulate gene expression by affecting the pattern of gene expression, enhancing the level of gene expression and driving the gene expression.

  13. Gene therapy prospects--intranasal delivery of therapeutic genes.

    Science.gov (United States)

    Podolska, Karolina; Stachurska, Anna; Hajdukiewicz, Karolina; Małecki, Maciej

    2012-01-01

    Gene therapy is recognized to be a novel method for the treatment of various disorders. Gene therapy strategies involve gene manipulation on broad biological processes responsible for the spreading of diseases. Cancer, monogenic diseases, vascular and infectious diseases are the main targets of gene therapy. In order to obtain valuable experimental and clinical results, sufficient gene transfer methods are required. Therapeutic genes can be administered into target tissues via gene carriers commonly defined as vectors. The retroviral, adenoviral and adeno-associated virus based vectors are most frequently used in the clinic. So far, gene preparations may be administered directly into target organs or by intravenous, intramuscular, intratumor or intranasal injections. It is common knowledge that the number of gene therapy clinical trials has rapidly increased. However, some limitations such as transfection efficiency and stable and long-term gene expression are still not resolved. Consequently, great effort is focused on the evaluation of new strategies of gene delivery. There are many expectations associated with intranasal delivery of gene preparations for the treatment of diseases. Intranasal delivery of therapeutic genes is regarded as one of the most promising forms of pulmonary gene therapy research. Gene therapy based on inhalation of gene preparations offers an alternative way for the treatment of patients suffering from such lung diseases as cystic fibrosis, alpha-1-antitrypsin defect, or cancer. Experimental and first clinical trials based on plasmid vectors or recombinant viruses have revealed that gene preparations can effectively deliver therapeutic or marker genes to the cells of the respiratory tract. The noninvasive intranasal delivery of gene preparations or conventional drugs seems to be very encouraging, although basic scientific research still has to continue.

  14. FunGene: the Functional Gene Pipeline and Repository

    Directory of Open Access Journals (Sweden)

    Jordan A. Fish

    2013-10-01

    Full Text Available Ribosomal RNA genes have become the standard molecular markers for microbial community analysis for good reasons, including universal occurrence in cellular organisms, availability of large databases, and ease of rRNA gene region amplification and analysis. As markers, however, rRNA genes have some significant limitations. The rRNA genes are often present in multiple copies, unlike most protein-coding genes. The slow rate of change in rRNA genes means that multiple species sometimes share identical 16S rRNA gene sequences, while many more species share identical sequences in the short 16S rRNA regions commonly analyzed. In addition, the genes involved in many important processes are not distributed in a phylogenetically coherent manner, potentially due to gene loss or horizontal gene transfer.While rRNA genes remain the most commonly used markers, key genes in ecologically important pathways, e.g., those involved in carbon and nitrogen cycling, can provide important insights into community composition and function not obtainable through rRNA analysis. However, working with ecofunctional gene data requires some tools beyond those required for rRNA analysis. To address this, our Functional Gene Pipeline and Repository (FunGene; http://fungene.cme.msu.edu/ offers databases of many common ecofunctional genes and proteins, as well as integrated tools that allow researchers to browse these collections and choose subsets for further analysis, build phylogenetic trees, test primers and probes for coverage, and download aligned sequences. Additional FunGene tools are specialized to process coding gene amplicon data. For example, FrameBot produces frameshift-corrected protein and DNA sequences from raw reads while finding the most closely related protein reference sequence. These tools can help provide better insight into microbial communities by directly studying key genes involved in important ecological processes.

  15. Gene decay in archaea

    Directory of Open Access Journals (Sweden)

    M. W. J. van Passel

    2007-01-01

    Full Text Available The gene-dense chromosomes of archaea and bacteria were long thought to be devoid of pseudogenes, but with the massive increase in available genome sequences, whole genome comparisons between closely related species have identified mutations that have rendered numerous genes inactive. Comparative analyses of sequenced archaeal genomes revealed numerous pseudogenes, which can constitute up to 8.6% of the annotated coding sequences in some genomes. The largest proportion of pseudogenes is created by gene truncations, followed by frameshift mutations. Within archaeal genomes, large numbers of pseudogenes contain more than one inactivating mutation, suggesting that pseudogenes are deleted from the genome more slowly in archaea than in bacteria. Although archaea seem to retain pseudogenes longer than do bacteria, most archaeal genomes have unique repertoires of pseudogenes.

  16. A review on microcephaly genes

    Directory of Open Access Journals (Sweden)

    Irshad S.

    2012-06-01

    Full Text Available This review aims to summarize the recent findings regarding microcephaly genes. We have discussed the molecular genetics studies of microcephaly genes including a comprehensive appraisal of the seven mapped loci (MCPH1–MCPH7, their corresponding genes and protein products of the genes, their likely role in normal brain development and the details of the mutations reported in these genes.

  17. Gene therapy for skin diseases.

    Science.gov (United States)

    Gorell, Emily; Nguyen, Ngon; Lane, Alfred; Siprashvili, Zurab

    2014-04-01

    The skin possesses qualities that make it desirable for gene therapy, and studies have focused on gene therapy for multiple cutaneous diseases. Gene therapy uses a vector to introduce genetic material into cells to alter gene expression, negating a pathological process. This can be accomplished with a variety of viral vectors or nonviral administrations. Although results are promising, there are several potential pitfalls that must be addressed to improve the safety profile to make gene therapy widely available clinically.

  18. Gene Therapy for Skin Diseases

    OpenAIRE

    2014-01-01

    The skin possesses qualities that make it desirable for gene therapy, and studies have focused on gene therapy for multiple cutaneous diseases. Gene therapy uses a vector to introduce genetic material into cells to alter gene expression, negating a pathological process. This can be accomplished with a variety of viral vectors or nonviral administrations. Although results are promising, there are several potential pitfalls that must be addressed to improve the safety profile to make gene thera...

  19. Correlating Expression Data with Gene Function Using Gene Ontology

    Institute of Scientific and Technical Information of China (English)

    LIU,Qi; DENG,Yong; WANG,Chuan; SHI,Tie-Liu; LI,Yi-Xue

    2006-01-01

    Clustering is perhaps one of the most widely used tools for microarray data analysis. Proposed roles for genes of unknown function are inferred from clusters of genes similarity expressed across many biological conditions.However, whether function annotation by similarity metrics is reliable or not and to what extent the similarity in gene expression patterns is useful for annotation of gene functions, has not been evaluated. This paper made a comprehensive research on the correlation between the similarity of expression data and of gene functions using Gene Ontology. It has been found that although the similarity in expression patterns and the similarity in gene functions are significantly dependent on each other, this association is rather weak. In addition, among the three categories of Gene Ontology, the similarity of expression data is more useful for cellular component annotation than for biological process and molecular function. The results presented are interesting for the gene functions prediction research area.

  20. The gene tree delusion.

    Science.gov (United States)

    Springer, Mark S; Gatesy, John

    2016-01-01

    Higher-level relationships among placental mammals are mostly resolved, but several polytomies remain contentious. Song et al. (2012) claimed to have resolved three of these using shortcut coalescence methods (MP-EST, STAR) and further concluded that these methods, which assume no within-locus recombination, are required to unravel deep-level phylogenetic problems that have stymied concatenation. Here, we reanalyze Song et al.'s (2012) data and leverage these re-analyses to explore key issues in systematics including the recombination ratchet, gene tree stoichiometry, the proportion of gene tree incongruence that results from deep coalescence versus other factors, and simulations that compare the performance of coalescence and concatenation methods in species tree estimation. Song et al. (2012) reported an average locus length of 3.1 kb for the 447 protein-coding genes in their phylogenomic dataset, but the true mean length of these loci (start codon to stop codon) is 139.6 kb. Empirical estimates of recombination breakpoints in primates, coupled with consideration of the recombination ratchet, suggest that individual coalescence genes (c-genes) approach ∼12 bp or less for Song et al.'s (2012) dataset, three to four orders of magnitude shorter than the c-genes reported by these authors. This result has general implications for the application of coalescence methods in species tree estimation. We contend that it is illogical to apply coalescence methods to complete protein-coding sequences. Such analyses amalgamate c-genes with different evolutionary histories (i.e., exons separated by >100,000 bp), distort true gene tree stoichiometry that is required for accurate species tree inference, and contradict the central rationale for applying coalescence methods to difficult phylogenetic problems. In addition, Song et al.'s (2012) dataset of 447 genes includes 21 loci with switched taxonomic names, eight duplicated loci, 26 loci with non-homologous sequences that are

  1. Neighboring Genes Show Correlated Evolution in Gene Expression

    Science.gov (United States)

    Ghanbarian, Avazeh T.; Hurst, Laurence D.

    2015-01-01

    When considering the evolution of a gene’s expression profile, we commonly assume that this is unaffected by its genomic neighborhood. This is, however, in contrast to what we know about the lack of autonomy between neighboring genes in gene expression profiles in extant taxa. Indeed, in all eukaryotic genomes genes of similar expression-profile tend to cluster, reflecting chromatin level dynamics. Does it follow that if a gene increases expression in a particular lineage then the genomic neighbors will also increase in their expression or is gene expression evolution autonomous? To address this here we consider evolution of human gene expression since the human-chimp common ancestor, allowing for both variation in estimation of current expression level and error in Bayesian estimation of the ancestral state. We find that in all tissues and both sexes, the change in gene expression of a focal gene on average predicts the change in gene expression of neighbors. The effect is highly pronounced in the immediate vicinity (genes increasing their expression in humans tend to avoid nuclear lamina domains and be enriched for the gene activator 5-hydroxymethylcytosine, we conclude that, most probably owing to chromatin level control of gene expression, a change in gene expression of one gene likely affects the expression evolution of neighbors, what we term expression piggybacking, an analog of hitchhiking. PMID:25743543

  2. Genotipificacion y subtipificacion molecular de cepas de Clostridium perfringens aisladas en alpacas muertas por enterotoxemia

    National Research Council Canada - National Science Library

    Perez, David; Maturrano, Lenin; Rosadio, Raul

    2012-01-01

    ...), asi como la deteccion de genes secundarios codificantes de la enterotoxina (cpe) y toxina [beta]2 (subtipificacion). El ADN bacteriano de las 47 cepas fue sometido a prueba de PCR multiple evidenciando que 46/47...

  3. Searching for speciation genes

    DEFF Research Database (Denmark)

    Holt, Benjamin George; Côté, Isabelle M; Emerson, Brent C

    2011-01-01

    Closely related species that show clear phenotypic divergence, but without obvious geographic barriers, can provide opportunities to study how diversification can occur when opportunities for allopatric speciation are limited. We examined genetic divergence in the coral reef fish genus Hypoplectr...... evidence for genes that may be associated with colour morphotype in the genus Hypoplectrus....

  4. Gene therapy in ophthalmology

    Directory of Open Access Journals (Sweden)

    Satagopan Uthra

    2009-01-01

    Full Text Available It has been more than a year since ophthalmologists and scientists under Dr. Robin Ali′s team at the Moorsfield Eye Hospital and the Institute of Ophthalmology, University College London, successfully treated patients with a severely blinding disease, Leber′s congenital amaurosis (LCA using gene therapy. This success does not look to be transient, and this achievement in gene replacement therapy clinical trial for LCA has instilled hope in numerous families with patients suffering from this and similar retinal degenerative diseases, for whom restoration of lost vision has remained a distant dream so far. The encouragement that this success has given is expected to also lead to start of clinical trials for other blinding ocular diseases for which gene therapy experiments at the laboratory and animal levels have been successful. This article reviews the various studies that have led to the understanding of gene therapy outcomes in human ocular diseases and attempts to provide a brief sketch of successful clinical trials.

  5. Old genes experience stronger translational selection than young genes.

    Science.gov (United States)

    Yin, Hongyan; Ma, Lina; Wang, Guangyu; Li, Mengwei; Zhang, Zhang

    2016-09-15

    Selection on synonymous codon usage for translation efficiency and/or accuracy has been identified as a widespread mechanism in many living organisms. However, it remains unknown whether translational selection associates closely with gene age and acts differentially on genes with different evolutionary ages. To address this issue, here we investigate the strength of translational selection acting on different aged genes in human. Our results show that old genes present stronger translational selection than young genes, demonstrating that translational selection correlates positively with gene age. We further explore the difference of translational selection in duplicates vs. singletons and in housekeeping vs. tissue-specific genes. We find that translational selection acts comparably in old singletons and old duplicates and stronger translational selection in old genes is contributed primarily by housekeeping genes. For young genes, contrastingly, singletons experience stronger translational selection than duplicates, presumably due to redundant function of duplicated genes during their early evolutionary stage. Taken together, our results indicate that translational selection acting on a gene would not be constant during all stages of evolution, associating closely with gene age. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Genes2FANs: connecting genes through functional association networks

    Directory of Open Access Journals (Sweden)

    Dannenfelser Ruth

    2012-07-01

    Full Text Available Abstract Background Protein-protein, cell signaling, metabolic, and transcriptional interaction networks are useful for identifying connections between lists of experimentally identified genes/proteins. However, besides physical or co-expression interactions there are many ways in which pairs of genes, or their protein products, can be associated. By systematically incorporating knowledge on shared properties of genes from diverse sources to build functional association networks (FANs, researchers may be able to identify additional functional interactions between groups of genes that are not readily apparent. Results Genes2FANs is a web based tool and a database that utilizes 14 carefully constructed FANs and a large-scale protein-protein interaction (PPI network to build subnetworks that connect lists of human and mouse genes. The FANs are created from mammalian gene set libraries where mouse genes are converted to their human orthologs. The tool takes as input a list of human or mouse Entrez gene symbols to produce a subnetwork and a ranked list of intermediate genes that are used to connect the query input list. In addition, users can enter any PubMed search term and then the system automatically converts the returned results to gene lists using GeneRIF. This gene list is then used as input to generate a subnetwork from the user’s PubMed query. As a case study, we applied Genes2FANs to connect disease genes from 90 well-studied disorders. We find an inverse correlation between the counts of links connecting disease genes through PPI and links connecting diseases genes through FANs, separating diseases into two categories. Conclusions Genes2FANs is a useful tool for interpreting the relationships between gene/protein lists in the context of their various functions and networks. Combining functional association interactions with physical PPIs can be useful for revealing new biology and help form hypotheses for further experimentation. Our

  7. Industrial scale gene synthesis.

    Science.gov (United States)

    Notka, Frank; Liss, Michael; Wagner, Ralf

    2011-01-01

    The most recent developments in the area of deep DNA sequencing and downstream quantitative and functional analysis are rapidly adding a new dimension to understanding biochemical pathways and metabolic interdependencies. These increasing insights pave the way to designing new strategies that address public needs, including environmental applications and therapeutic inventions, or novel cell factories for sustainable and reconcilable energy or chemicals sources. Adding yet another level is building upon nonnaturally occurring networks and pathways. Recent developments in synthetic biology have created economic and reliable options for designing and synthesizing genes, operons, and eventually complete genomes. Meanwhile, high-throughput design and synthesis of extremely comprehensive DNA sequences have evolved into an enabling technology already indispensable in various life science sectors today. Here, we describe the industrial perspective of modern gene synthesis and its relationship with synthetic biology. Gene synthesis contributed significantly to the emergence of synthetic biology by not only providing the genetic material in high quality and quantity but also enabling its assembly, according to engineering design principles, in a standardized format. Synthetic biology on the other hand, added the need for assembling complex circuits and large complexes, thus fostering the development of appropriate methods and expanding the scope of applications. Synthetic biology has also stimulated interdisciplinary collaboration as well as integration of the broader public by addressing socioeconomic, philosophical, ethical, political, and legal opportunities and concerns. The demand-driven technological achievements of gene synthesis and the implemented processes are exemplified by an industrial setting of large-scale gene synthesis, describing production from order to delivery.

  8. Endovascular Gene Delivery from a Stent Platform: Gene- Eluting Stents.

    Science.gov (United States)

    Fishbein, Ilia; Chorny, Michael; Adamo, Richard F; Forbes, Scott P; Corrales, Ricardo A; Alferiev, Ivan S; Levy, Robert J

    A synergistic impact of research in the fields of post-angioplasty restenosis, drug-eluting stents and vascular gene therapy over the past 15 years has shaped the concept of gene-eluting stents. Gene-eluting stents hold promise of overcoming some biological and technical problems inherent to drug-eluting stent technology. As the field of gene-eluting stents matures it becomes evident that all three main design modules of a gene-eluting stent: a therapeutic transgene, a vector and a delivery system are equally important for accomplishing sustained inhibition of neointimal formation in arteries treated with gene delivery stents. This review summarizes prior work on stent-based gene delivery and discusses the main optimization strategies required to move the field of gene-eluting stents to clinical translation.

  9. Tumor-specific gene expression patterns with gene expression profiles

    Institute of Scientific and Technical Information of China (English)

    RUAN Xiaogang; LI Yingxin; LI Jiangeng; GONG Daoxiong; WANG Jinlian

    2006-01-01

    Gene expression profiles of 14 common tumors and their counterpart normal tissues were analyzed with machine learning methods to address the problem of selection of tumor-specific genes and analysis of their differential expressions in tumor tissues. First, a variation of the Relief algorithm, "RFE_Relief algorithm" was proposed to learn the relations between genes and tissue types. Then, a support vector machine was employed to find the gene subset with the best classification performance for distinguishing cancerous tissues and their counterparts. After tissue-specific genes were removed, cross validation experiments were employed to demonstrate the common deregulated expressions of the selected gene in tumor tissues. The results indicate the existence of a specific expression fingerprint of these genes that is shared in different tumor tissues, and the hallmarks of the expression patterns of these genes in cancerous tissues are summarized at the end of this paper.

  10. Entrez Gene: gene-centered information at NCBI.

    Science.gov (United States)

    Maglott, Donna; Ostell, Jim; Pruitt, Kim D; Tatusova, Tatiana

    2011-01-01

    Entrez Gene (http://www.ncbi.nlm.nih.gov/gene) is National Center for Biotechnology Information (NCBI)'s database for gene-specific information. Entrez Gene maintains records from genomes which have been completely sequenced, which have an active research community to submit gene-specific information, or which are scheduled for intense sequence analysis. The content represents the integration of curation and automated processing from NCBI's Reference Sequence project (RefSeq), collaborating model organism databases, consortia such as Gene Ontology and other databases within NCBI. Records in Entrez Gene are assigned unique, stable and tracked integers as identifiers. The content (nomenclature, genomic location, gene products and their attributes, markers, phenotypes and links to citations, sequences, variation details, maps, expression, homologs, protein domains and external databases) is available via interactive browsing through NCBI's Entrez system, via NCBI's Entrez programming utilities (E-Utilities) and for bulk transfer by FTP.

  11. Gene set analysis for longitudinal gene expression data

    Directory of Open Access Journals (Sweden)

    Piepho Hans-Peter

    2011-07-01

    Full Text Available Abstract Background Gene set analysis (GSA has become a successful tool to interpret gene expression profiles in terms of biological functions, molecular pathways, or genomic locations. GSA performs statistical tests for independent microarray samples at the level of gene sets rather than individual genes. Nowadays, an increasing number of microarray studies are conducted to explore the dynamic changes of gene expression in a variety of species and biological scenarios. In these longitudinal studies, gene expression is repeatedly measured over time such that a GSA needs to take into account the within-gene correlations in addition to possible between-gene correlations. Results We provide a robust nonparametric approach to compare the expressions of longitudinally measured sets of genes under multiple treatments or experimental conditions. The limiting distributions of our statistics are derived when the number of genes goes to infinity while the number of replications can be small. When the number of genes in a gene set is small, we recommend permutation tests based on our nonparametric test statistics to achieve reliable type I error and better power while incorporating unknown correlations between and within-genes. Simulation results demonstrate that the proposed method has a greater power than other methods for various data distributions and heteroscedastic correlation structures. This method was used for an IL-2 stimulation study and significantly altered gene sets were identified. Conclusions The simulation study and the real data application showed that the proposed gene set analysis provides a promising tool for longitudinal microarray analysis. R scripts for simulating longitudinal data and calculating the nonparametric statistics are posted on the North Dakota INBRE website http://ndinbre.org/programs/bioinformatics.php. Raw microarray data is available in Gene Expression Omnibus (National Center for Biotechnology Information with

  12. Optimal Reference Genes for Gene Expression Normalization in Trichomonas vaginalis.

    Science.gov (United States)

    dos Santos, Odelta; de Vargas Rigo, Graziela; Frasson, Amanda Piccoli; Macedo, Alexandre José; Tasca, Tiana

    2015-01-01

    Trichomonas vaginalis is the etiologic agent of trichomonosis, the most common non-viral sexually transmitted disease worldwide. This infection is associated with several health consequences, including cervical and prostate cancers and HIV acquisition. Gene expression analysis has been facilitated because of available genome sequences and large-scale transcriptomes in T. vaginalis, particularly using quantitative real-time polymerase chain reaction (qRT-PCR), one of the most used methods for molecular studies. Reference genes for normalization are crucial to ensure the accuracy of this method. However, to the best of our knowledge, a systematic validation of reference genes has not been performed for T. vaginalis. In this study, the transcripts of nine candidate reference genes were quantified using qRT-PCR under different cultivation conditions, and the stability of these genes was compared using the geNorm and NormFinder algorithms. The most stable reference genes were α-tubulin, actin and DNATopII, and, conversely, the widely used T. vaginalis reference genes GAPDH and β-tubulin were less stable. The PFOR gene was used to validate the reliability of the use of these candidate reference genes. As expected, the PFOR gene was upregulated when the trophozoites were cultivated with ferrous ammonium sulfate when the DNATopII, α-tubulin and actin genes were used as normalizing gene. By contrast, the PFOR gene was downregulated when the GAPDH gene was used as an internal control, leading to misinterpretation of the data. These results provide an important starting point for reference gene selection and gene expression analysis with qRT-PCR studies of T. vaginalis.

  13. Dominance from the perspective of gene-gene and gene-chemical interactions.

    Science.gov (United States)

    Gladki, Arkadiusz; Zielenkiewicz, Piotr; Kaczanowski, Szymon

    2016-02-01

    In this study, we used genetic interaction (GI) and gene-chemical interaction (GCI) data to compare mutations with different dominance phenotypes. Our analysis focused primarily on Saccharomyces cerevisiae, where haploinsufficient genes (HI; genes with dominant loss-of-function mutations) were found to be participating in gene expression processes, namely, the translation and regulation of gene transcription. Non-ribosomal HI genes (mainly regulators of gene transcription) were found to have more GIs and GCIs than haplosufficient (HS) genes. Several properties seem to lead to the enrichment of interactions, most notably, the following: importance, pleiotropy, gene expression level and gene expression variation. Importantly, after these properties were appropriately considered in the analysis, the correlation between dominance and GI/GCI degrees was still observed. Strikingly, for the GCIs of heterozygous strains, haploinsufficiency was the only property significantly correlated with the number of GCIs. We found ribosomal HI genes to be depleted in GIs/GCIs. This finding can be explained by their high variation in gene expression under different genetic backgrounds and environmental conditions. We observed the same distributions of GIs among non-ribosomal HI, ribosomal HI and HS genes in three other species: Schizosaccharomyces pombe, Drosophila melanogaster and Homo sapiens. One potentially interesting exception was the lack of significant differences in the degree of GIs between non-ribosomal HI and HS genes in Schizosaccharomyces pombe.

  14. Gene-gene interaction between tuberculosis candidate genes in a South African population.

    Science.gov (United States)

    de Wit, Erika; van der Merwe, Lize; van Helden, Paul D; Hoal, Eileen G

    2011-02-01

    In a complex disease such as tuberculosis (TB) it is increasingly evident that gene-gene interactions play a far more important role in an individual's susceptibility to develop the disease than single polymorphisms on their own, as one gene can enhance or hinder the expression of another gene. Gene-gene interaction analysis is a new approach to elucidate susceptibility to TB. The possibility of gene-gene interactions was assessed, focusing on 11 polymorphisms in nine genes (DC-SIGN, IFN-γ, IFNGR1, IL-8, IL-1Ra, MBL, NRAMP1, RANTES, and SP-D) that have been associated with TB, some repeatedly. An optimal model, which best describes and predicts TB case-control status, was constructed. Significant interactions were detected between eight pairs of variants. The models fitted the observed data extremely well, with p activation is greatly enhanced by IFN-γ and IFN-γ response elements that are present in the human NRAMP1 promoter region, providing further evidence for their interaction. This study enabled us to test the theory that disease outcome may be due to interaction of several gene effects. With eight instances of statistically significant gene-gene interactions, the importance of epistasis is clearly identifiable in this study. Methods for studying gene-gene interactions are based on a multilocus and multigene approach, consistent with the nature of complex-trait diseases, and may provide the paradigm for future genetic studies of TB.

  15. Gene doping in modern sport.

    Directory of Open Access Journals (Sweden)

    MAREK SAWCZUK

    2009-01-01

    Full Text Available Background: The subject of this paper is gene doping, which should be understood as "he non-therapeutic use of cells, genes, genetic elements, or of the modulation of gene expression, having the capacity to improve athletic performance". The authors of this work, based on the review of literature and previous research, make an attempt at wider characterization of gene doping and the discussion of related potential threats.Methods: This is a comprehensive survey of literature on the latest applications of molecular biology in medicine. The analysis involves a dozen scientific databases examined in order to find genes used in gene therapy and potentially useful in gene doping. Results: The obtained results enable better recognition of gene doping and indicate genes used in medicine that could be used in gene doping. This paper describes potential effects of their use and associated risk, and predicts the possible developments of gene doping in the future. Conclusion: Gene doping is undoubtedly a part of modern sport. Although WADA included gene doping on the list of banned methods as early as 2004, as previously stated above, it has not managed to develop efficient methods of detection.

  16. [Gene pool and gene geography of the USSR population].

    Science.gov (United States)

    Rychkov, Iu G; Balanovskaia, E V

    1992-01-01

    Gene pool and gene geography are discussed from the point of view of their conceptual history beginning from the original concept of A.S. Serebrovskiĭ (1928). Difference between the present-day gene geography and gene geography of gene pool is accentuated: the former only represents a portion of the latter. Historical and territorial integrity of the USSR population gene pool, in conjunction with its huge diversity, is the main problem being analysed by various means of computerized genetic cartography. Coupled with the gene frequency mapping, following methods were also used: mapping of average heterozygosity, of interpopulation differentiation, of principal component scores and mapping of geographical trend for each mapped genetic parameter. The work is based on 100 allelic genes and haplotypes from 30 independent loci studied on the average in 225 local populations. Statistical analysis of gene geographical maps is based on 3975 nodes of regular cartographic net for the USSR territory. The wind rose of systematic changes in the USSR gene pool has three main geographic orientations: W-E, SW-NE and S-N. At the same time, there are only two main systematic forces of gene pool evolution: the force of social history with predominant W-E orientation and the force of natural history with predominant S-N orientation of their actions. The heterozygosity level of gene pool declines strictly in accordance with the resultant in the SW-NE direction.

  17. Immunotherapy and gene therapy.

    Science.gov (United States)

    Simpson, Elizabeth

    2004-02-01

    The Immunotherapy and Gene Therapy meeting of the Academy of Medical Sciences reviewed the state-of-the-art and translational prospects for therapeutic interventions aimed at killing tumor cells, correcting genetic defects and developing vaccines for chronic infections. Crucial basic science concepts and information about dendritic cells, the structure and function of T-cell receptors, and manipulation of the immune response by cytokine antagonists and peptides were presented. This information underpins vaccine design and delivery, as well as attempts to immunomodulate autoimmune disease. Results from studies using anticancer DNA vaccines, which include appropriate signals for both the innate and adaptive immune response, were presented in several talks. The vaccines incorporated helper epitopes and cancer target epitopes such as immunoglobulin idiotypes (for lymphomas and myelomas), melanoma-associated antigens (for melanoma and other solid tumors) and minor histocompatibility antigens (for leukemia). The results of using vaccines employing similar principles and designed to reduce viral load in HIV/AIDS patients were also presented. The introduction of suicide genes incorporating the bacterial enzyme nitroreductase gene (ntr) targeted at tumor cells prior to administration of the prodrug CB-1954, converted by ntr into a toxic alkylating agent, was discussed against the background of clinical trials and improved suicide gene design. The introduction into hematopoietic stem cells of missing genes for the common gamma-chain, deficiency of which causes severe combined immunodeficiency (SCID), used similar retroviral transduction. The outcome of treating six SCID patients in the UK, and ten in France was successful immune reconstitution in the majority of patients, but in two of the French cases a complication of lymphoproliferative disease due to insertional mutagenesis was observed. The adoptive transfer of T-cells specific for minor histocompatibility antigens (for

  18. Bacterial Genome Editing with CRISPR-Cas9: Deletion, Integration, Single Nucleotide Modification, and Desirable "Clean" Mutant Selection in Clostridium beijerinckii as an Example.

    Science.gov (United States)

    Wang, Yi; Zhang, Zhong-Tian; Seo, Seung-Oh; Lynn, Patrick; Lu, Ting; Jin, Yong-Su; Blaschek, Hans P

    2016-07-15

    CRISPR-Cas9 has been demonstrated as a transformative genome engineering tool for many eukaryotic organisms; however, its utilization in bacteria remains limited and ineffective. Here we explored Streptococcus pyogenes CRISPR-Cas9 for genome editing in Clostridium beijerinckii (industrially significant but notorious for being difficult to metabolically engineer) as a representative attempt to explore CRISPR-Cas9 for genome editing in microorganisms that previously lacked sufficient genetic tools. By combining inducible expression of Cas9 and plasmid-borne editing templates, we successfully achieved gene deletion and integration with high efficiency in single steps. We further achieved single nucleotide modification by applying innovative two-step approaches, which do not rely on availability of Protospacer Adjacent Motif sequences. Severe vector integration events were observed during the genome engineering process, which is likely difficult to avoid but has never been reported by other researchers for the bacterial genome engineering based on homologous recombination with plasmid-borne editing templates. We then further successfully employed CRISPR-Cas9 as an efficient tool for selecting desirable "clean" mutants in this study. The approaches we developed are broadly applicable and will open the way for precise genome editing in diverse microorganisms.

  19. SOX genes: architects of development.

    Science.gov (United States)

    Prior, H M; Walter, M A

    1996-07-01

    Development in higher organisms involves complex genetic regulation at the molecular level. The emerging picture of development control includes several families of master regulatory genes which can affect the expression of down-stream target genes in developmental cascade pathways. One new family of such development regulators is the SOX gene family. The SOX genes are named for a shared motif called the SRY box a region homologous to the DNA-binding domain of SRY, the mammalian sex determining gene. Like SRY, SOX genes play important roles in chordate development. At least a dozen human SOX genes have been identified and partially characterized (Tables 1 and 2). Mutations in SOX9 have recently been linked to campomelic dysplasia and autosomal sex reversal, and other SOX genes may also be associated with human disease.

  20. Brains, genes, and primates.

    Science.gov (United States)

    Izpisua Belmonte, Juan Carlos; Callaway, Edward M; Caddick, Sarah J; Churchland, Patricia; Feng, Guoping; Homanics, Gregg E; Lee, Kuo-Fen; Leopold, David A; Miller, Cory T; Mitchell, Jude F; Mitalipov, Shoukhrat; Moutri, Alysson R; Movshon, J Anthony; Okano, Hideyuki; Reynolds, John H; Ringach, Dario; Sejnowski, Terrence J; Silva, Afonso C; Strick, Peter L; Wu, Jun; Zhang, Feng

    2015-05-06

    One of the great strengths of the mouse model is the wide array of genetic tools that have been developed. Striking examples include methods for directed modification of the genome, and for regulated expression or inactivation of genes. Within neuroscience, it is now routine to express reporter genes, neuronal activity indicators, and opsins in specific neuronal types in the mouse. However, there are considerable anatomical, physiological, cognitive, and behavioral differences between the mouse and the human that, in some areas of inquiry, limit the degree to which insights derived from the mouse can be applied to understanding human neurobiology. Several recent advances have now brought into reach the goal of applying these tools to understanding the primate brain. Here we describe these advances, consider their potential to advance our understanding of the human brain and brain disorders, discuss bioethical considerations, and describe what will be needed to move forward.

  1. Alphaviruses in Gene Therapy

    Directory of Open Access Journals (Sweden)

    Kenneth Lundstrom

    2009-04-01

    Full Text Available Alphaviruses are enveloped single stranded RNA viruses, which as gene therapy vectors provide high-level transient gene expression. Semliki Forest virus (SFV, Sindbis virus (SIN and Venezuelan Equine Encephalitis (VEE virus have been engineered as efficient replication-deficient and -competent expression vectors. Alphavirus vectors have frequently been used as vehicles for tumor vaccine generation. Moreover, SFV and SIN vectors have been applied for intratumoral injections in animals implanted with tumor xenografts. SIN vectors have demonstrated natural tumor targeting, which might permit systemic vector administration. Another approach for systemic delivery of SFV has been to encapsulate replication-deficient viral particles in liposomes, which can provide passive targeting to tumors and allow repeated administration without host immune responses. This approach has demonstrated safe delivery of encapsulated SFV particles to melanoma and kidney carcinoma patients in a phase I trial. Finally, the prominent neurotropism of alphaviruses make them attractive for the treatment of CNS-related diseases.

  2. Gene Disease Diagnostic System

    Institute of Scientific and Technical Information of China (English)

    黄国亮; 张腾飞; 程京; 周玉祥; 刘诚迅; 金国藩; 邬敏贤; 严瑛白; 杨蓉

    2002-01-01

    Binary optics, where the optical element can be fabricated on a thin glass plate with micro-ion-etching film layer, has been widely applied in recent years. A novel optical scanning system for gene disease diagnostics described in this paper has four kinds of optical devices, including beam splitters, an array lens, an array filter and detection arrays. A software was developed to design the binary optics system using an iterative method. Two beam splitters were designed and fabricated, which can divide a beam into a 9×9 array or into a 13×13 array. The beam splitters have good diffraction efficiencies (>70%) and an even energy distribution. The gene disease diagnostic system is a portable biochip and binary optics technology. The binary optical devices in the non-confocal scanning system can raise the fluorescence detection sensitivity of the micro-array hybrid biochip.

  3. Gene therapy for mucopolysaccharidosis

    Science.gov (United States)

    Ponder, Katherine P; Haskins, Mark E

    2012-01-01

    Mucopolysaccharidoses (MPS) are due to deficiencies in activities of lysosomal enzymes that degrade glycosaminoglycans. Some attempts at gene therapy for MPS in animal models have involved intravenous injection of vectors derived from an adeno-associated virus (AAV), adenovirus, retrovirus or a plasmid, which primarily results in expression in liver and secretion of the relevant enzyme into blood. Most vectors can correct disease in liver and spleen, although correction in other organs including the brain requires high enzyme activity in the blood. Alternative approaches are to transduce hematopoietic stem cells, or to inject a vector locally into difficult-to-reach sites such as the brain. Gene therapy holds great promise for providing a long-lasting therapeutic effect for MPS if safety issues can be resolved. PMID:17727324

  4. Gene Porter Bridwell

    Science.gov (United States)

    1994-01-01

    Gene Porter Bridwell served as the director of the Marshall Space Flight Center from January 6, 1994 until February 3, 1996, when he retired from NASA after thirty-four years service. Bridwell, a Marshall employee since 1962, had been Marshall's Space Shuttle Projects Office Director and Space Station Redesign Team deputy manager. Under Bridwell, Marshall worked to develop its role as a Center of Excellence for propulsion and for providing access to space.

  5. Gene Porter Bridwell

    Science.gov (United States)

    1994-01-01

    Gene Porter Bridwell served as the director of the Marshall Space Flight Center from January 6, 1994 until February 3, 1996, when he retired from NASA after thirty-four years service. Bridwell, a Marshall employee since 1962, had been Marshall's Space Shuttle Projects Office Director and Space Station Redesign Team deputy manager. Under Bridwell, Marshall worked to develop its role as a Center of Excellence for propulsion and for providing access to space.

  6. Epigenetics: beyond genes

    CSIR Research Space (South Africa)

    Fossey, A

    2009-06-01

    Full Text Available to neighbouring euchromatic genes, known as position effect variegation and can be transmitted through mitosis, forming the basis of epigenetic inheritance from one cell generation to another; creating cellular memory (Brzeski and Jerzmanowski, 2004... life form, supports meiosis that produces haploid male and female spores and initiates the gametophytic generation. Gametogenesis and subsequent fertilisation take place when gametophytic and sporophytic structures interact. The product...

  7. PRRT2 gene mutations

    Science.gov (United States)

    Gardiner, Alice R.; Bhatia, Kailash P.; Stamelou, Maria; Dale, Russell C.; Kurian, Manju A.; Schneider, Susanne A.; Wali, G.M.; Counihan, Tim; Schapira, Anthony H.; Spacey, Sian D.; Valente, Enza-Maria; Silveira-Moriyama, Laura; Teive, Hélio A.G.; Raskin, Salmo; Sander, Josemir W.; Lees, Andrew; Warner, Tom; Kullmann, Dimitri M.; Wood, Nicholas W.; Hanna, Michael

    2012-01-01

    ABSTRACT Objective: The proline-rich transmembrane protein (PRRT2) gene was recently identified using exome sequencing as the cause of autosomal dominant paroxysmal kinesigenic dyskinesia (PKD) with or without infantile convulsions (IC) (PKD/IC syndrome). Episodic neurologic disorders, such as epilepsy, migraine, and paroxysmal movement disorders, often coexist and are thought to have a shared channel-related etiology. To investigate further the frequency, spectrum, and phenotype of PRRT2 mutations, we analyzed this gene in 3 large series of episodic neurologic disorders with PKD/IC, episodic ataxia (EA), and hemiplegic migraine (HM). Methods: The PRRT2 gene was sequenced in 58 family probands/sporadic individuals with PKD/IC, 182 with EA, 128 with HM, and 475 UK and 96 Asian controls. Results: PRRT2 genetic mutations were identified in 28 out of 58 individuals with PKD/IC (48%), 1/182 individuals with EA, and 1/128 individuals with HM. A number of loss-of-function and coding missense mutations were identified; the most common mutation found was the p.R217Pfs*8 insertion. Males were more frequently affected than females (ratio 52:32). There was a high proportion of PRRT2 mutations found in families and sporadic cases with PKD associated with migraine or HM (10 out of 28). One family had EA with HM and another large family had typical HM alone. Conclusions: This work expands the phenotype of mutations in the PRRT2 gene to include the frequent occurrence of migraine and HM with PKD/IC, and the association of mutations with EA and HM and with familial HM alone. We have also extended the PRRT2 mutation type and frequency in PKD and other episodic neurologic disorders. PMID:23077024

  8. Gene therapy in gastric cancer

    Institute of Scientific and Technical Information of China (English)

    Xu Chang-tai; Guo Xue-gang; Pan Bo-rong

    2003-01-01

    @@ 1 Introduction We have reviewed the gene therapy in gastrointestinal diseases[1]. Gastric cancer is common in China[2~20] ,and its early diagnosis andtreatment are still difficult up to now[13~36]. The expression of anexogenous gene introduced by gene therapy into patients with gliomascan be monitored non- invasively by positron- emission tomography[4]. In recent years, gene study in cancer is a hotspot, and great progress hasbeen achieved[33~41].

  9. Gene therapy for gastric diseases.

    OpenAIRE

    Fumoto, Shintaro; Nishi, Junya; Nakamura, Junzo; Nishida, Koyo

    2008-01-01

    Gene therapy for gastric cancer and gastric ulcer is a rationalized strategy since various genes correlate with these diseases. Since gene expressions in non-target tissues/cells cause side effects, a selective gene delivery system targeted to the stomach and/or cancer must be developed. The route of vector transfer (direct injection, systemic, intraperitoneal, gastric serosal surface and oral administration) is an important issue which can determine efficacy and safety. Strategies for cancer...

  10. Genealogy and gene trees.

    Science.gov (United States)

    Rasmuson, Marianne

    2008-02-01

    Heredity can be followed in persons or in genes. Persons can be identified only a few generations back, but simplified models indicate that universal ancestors to all now living persons have occurred in the past. Genetic variability can be characterized as variants of DNA sequences. Data are available only from living persons, but from the pattern of variation gene trees can be inferred by means of coalescence models. The merging of lines backwards in time leads to a MRCA (most recent common ancestor). The time and place of living for this inferred person can give insights in human evolutionary history. Demographic processes are incorporated in the model, but since culture and customs are known to influence demography the models used ought to be tested against available genealogy. The Icelandic data base offers a possibility to do so and points to some discrepancies. Mitochondrial DNA and Y chromosome patterns give a rather consistent view of human evolutionary history during the latest 100 000 years but the earlier epochs of human evolution demand gene trees with longer branches. The results of such studies reveal as yet unsolved problems about the sources of our genome.

  11. Gene-gene and gene-environmental interactions of childhood asthma: a multifactor dimension reduction approach.

    Directory of Open Access Journals (Sweden)

    Ming-Wei Su

    Full Text Available BACKGROUND: The importance of gene-gene and gene-environment interactions on asthma is well documented in literature, but a systematic analysis on the interaction between various genetic and environmental factors is still lacking. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a population-based, case-control study comprised of seventh-grade children from 14 Taiwanese communities. A total of 235 asthmatic cases and 1,310 non-asthmatic controls were selected for DNA collection and genotyping. We examined the gene-gene and gene-environment interactions between 17 single-nucleotide polymorphisms in antioxidative, inflammatory and obesity-related genes, and childhood asthma. Environmental exposures and disease status were obtained from parental questionnaires. The model-free and non-parametrical multifactor dimensionality reduction (MDR method was used for the analysis. A three-way gene-gene interaction was elucidated between the gene coding glutathione S-transferase P (GSTP1, the gene coding interleukin-4 receptor alpha chain (IL4Ra and the gene coding insulin induced gene 2 (INSIG2 on the risk of lifetime asthma. The testing-balanced accuracy on asthma was 57.83% with a cross-validation consistency of 10 out of 10. The interaction of preterm birth and indoor dampness had the highest training-balanced accuracy at 59.09%. Indoor dampness also interacted with many genes, including IL13, beta-2 adrenergic receptor (ADRB2, signal transducer and activator of transcription 6 (STAT6. We also used likelihood ratio tests for interaction and chi-square tests to validate our results and all tests showed statistical significance. CONCLUSIONS/SIGNIFICANCE: The results of this study suggest that GSTP1, INSIG2 and IL4Ra may influence the lifetime asthma susceptibility through gene-gene interactions in schoolchildren. Home dampness combined with each one of the genes STAT6, IL13 and ADRB2 could raise the asthma risk.

  12. Gene therapy of cancer and development of therapeutic target gene

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang Min; Kwon, Hee Chung

    1998-04-01

    We applied HSV-tk/GCV strategy to orthotopic rat hepatoma model and showed anticancer effects of hepatoma. The increased expression of Lac Z gene after adenovirus-mediated gene delivery throughout hepatic artery was thought that is increased the possibility of gene therapy for curing hepatoma. With the construction of kGLP-laboratory, it is possible to produce a good quantity and quality of adenovirus in lage-scale production and purification of adenovirus vector. Also, the analysis of hepatoma related genes by PCR-LOH could be used for the diagnosis of patients and the development of therapeutic gene.

  13. Independent Gene Discovery and Testing

    Science.gov (United States)

    Palsule, Vrushalee; Coric, Dijana; Delancy, Russell; Dunham, Heather; Melancon, Caleb; Thompson, Dennis; Toms, Jamie; White, Ashley; Shultz, Jeffry

    2010-01-01

    A clear understanding of basic gene structure is critical when teaching molecular genetics, the central dogma and the biological sciences. We sought to create a gene-based teaching project to improve students' understanding of gene structure and to integrate this into a research project that can be implemented by instructors at the secondary level…

  14. Compositional gradients in Gramineae genes

    DEFF Research Database (Denmark)

    Wong, Gane Ka-Shu; Wang, Jun; Tao, Lin

    2002-01-01

    In this study, we describe a property of Gramineae genes, and perhaps all monocot genes, that is not observed in eudicot genes. Along the direction of transcription, beginning at the junction of the 5'-UTR and the coding region, there are gradients in GC content, codon usage, and amino-acid usage...

  15. Decationized polyplexes for gene delivery

    NARCIS (Netherlands)

    Novo, L.; Mastrobattista, E.; Nostrum, van C.F.; Lammers, T.G.G.M.; Hennink, W.E.

    2015-01-01

    Gene therapy has received much attention in the field of drug delivery. Synthetic, nonviral gene delivery systems have gained increasing attention as vectors for gene therapy mainly due to a favorable immunogenicity profile and ease of manufacturing as compared to viral vectors. The great majority o

  16. Ascidian gene-expression profiles

    OpenAIRE

    Jeffery, William R.

    2002-01-01

    With the advent of gene-expression profiling, a large number of genes can now be investigated simultaneously during critical stages of development. This approach will be particularly informative in studies of ascidians, basal chordates whose genomes and embryology are uniquely suited for mapping developmental gene networks.

  17. Gene electrotransfer in clinical trials

    DEFF Research Database (Denmark)

    Gehl, Julie

    2014-01-01

    Electroporation is increasingly being used for delivery of chemotherapy to tumors. Likewise, gene delivery by electroporation is rapidly gaining momentum for both vaccination purposes and for delivery of genes coding for other therapeutic molecules, such as chronic diseases or cancer. This chapte...... describes how gene therapy may be performed using electric pulses to enhance uptake and expression.......Electroporation is increasingly being used for delivery of chemotherapy to tumors. Likewise, gene delivery by electroporation is rapidly gaining momentum for both vaccination purposes and for delivery of genes coding for other therapeutic molecules, such as chronic diseases or cancer. This chapter...

  18. Gene therapy of liver cancer

    Institute of Scientific and Technical Information of China (English)

    Ruben Hernandez-Alcoceba; Bruno Sangro; Jesus Prieto

    2006-01-01

    The application of gene transfer technologies to the treatment of cancer has led to the development of new experimental approaches like gene directed enzyme/prodrug therapy (GDEPT), inhibition of oncogenes and restoration of tumor-suppressor genes. In addition,gene therapy has a big impact on other fields like cancer immunotherapy, anti-angiogenic therapy and virotherapy.These strategies are being evaluated for the treatment of primary and metastatic liver cancer and some of them have reached clinical phases. We present a review on the basis and the actual status of gene therapy approaches applied to liver cancer.

  19. Novel plasmid conferring kanamycin and tetracycline resistance in the turkey-derived Campylobacter jejuni strain 11601MD.

    Science.gov (United States)

    Crespo, M D; Altermann, E; Olson, J; Miller, W G; Chandrashekhar, K; Kathariou, S

    2016-07-01

    In Campylobacter spp., resistance to the antimicrobials kanamycin and tetracycline is frequently associated with plasmid-borne genes. However, relatively few plasmids of Campylobacter jejuni have been fully characterized to date. A novel plasmid (p11601MD; 44,095nt) harboring tet(O) was identified in C. jejuni strain 11601MD, which was isolated from the jejunum of a turkey produced conventionally in North Carolina. Analysis of the p11601MD sequence revealed the presence of a high-GC content cassette with four genes that included tet(O) and a putative aminoglycoside transferase gene (aphA-3) highly similar to kanamycin resistance determinants. Several genes putatively involved in conjugative transfer were also identified on the plasmid. These findings will contribute to a better understanding of the distribution of potentially self-mobilizing plasmids harboring antibiotic resistance determinants in Campylobacter spp. from turkeys and other sources.

  20. Classifying genes to the correct Gene Ontology Slim term in Saccharomyces cerevisiae using neighbouring genes with classification learning

    OpenAIRE

    Tsatsoulis Costas; Amthauer Heather A

    2010-01-01

    Abstract Background There is increasing evidence that gene location and surrounding genes influence the functionality of genes in the eukaryotic genome. Knowing the Gene Ontology Slim terms associated with a gene gives us insight into a gene's functionality by informing us how its gene product behaves in a cellular context using three different ontologies: molecular function, biological process, and cellular component. In this study, we analyzed if we could classify a gene in Saccharomyces ce...

  1. Gene finding in novel genomes

    Directory of Open Access Journals (Sweden)

    Korf Ian

    2004-05-01

    Full Text Available Abstract Background Computational gene prediction continues to be an important problem, especially for genomes with little experimental data. Results I introduce the SNAP gene finder which has been designed to be easily adaptable to a variety of genomes. In novel genomes without an appropriate gene finder, I demonstrate that employing a foreign gene finder can produce highly inaccurate results, and that the most compatible parameters may not come from the nearest phylogenetic neighbor. I find that foreign gene finders are more usefully employed to bootstrap parameter estimation and that the resulting parameters can be highly accurate. Conclusion Since gene prediction is sensitive to species-specific parameters, every genome needs a dedicated gene finder.

  2. Na(+) dependent acid-base transporters in the choroid plexus; insights from slc4 and slc9 gene deletion studies

    DEFF Research Database (Denmark)

    Christensen, Henriette L; Nguyen, An T; Pedersen, Fredrik D

    2013-01-01

    H regulation (slc4a7 and slc4a10). In some instances, removal of the proteins from the CPE (slc4a5, 7, and 10) causes changes in abundance and localization of non-target transporters known to be involved in pH regulation and CSF secretion. The focus of this review is to combine the insights gathered from...... with an unsurpassed transepithelial water and solute transport rate. Several members of the slc4a family of bicarbonate transporters are expressed in the CPE. In the basolateral membrane the electroneutral Na(+) dependent Cl(-)/HCO3 (-) exchanger, NCBE (slc4a10) is expressed. In the luminal membrane, the electrogenic...... Na(+):HCO3 (-) cotransporter, NBCe2 (slc4a5) is expressed. The electroneutral Na(+):HCO3 (-) cotransporter, NBCn1 (slc4a7), has been located in both membranes. In addition to the bicarbonate transporters, the Na(+)/H(+) exchanger, NHE1 (slc9a1), is located in the luminal membrane of the CPE...

  3. GeneDistiller--distilling candidate genes from linkage intervals.

    Directory of Open Access Journals (Sweden)

    Dominik Seelow

    Full Text Available BACKGROUND: Linkage studies often yield intervals containing several hundred positional candidate genes. Different manual or automatic approaches exist for the determination of the gene most likely to cause the disease. While the manual search is very flexible and takes advantage of the researchers' background knowledge and intuition, it may be very cumbersome to collect and study the relevant data. Automatic solutions on the other hand usually focus on certain models, remain "black boxes" and do not offer the same degree of flexibility. METHODOLOGY: We have developed a web-based application that combines the advantages of both approaches. Information from various data sources such as gene-phenotype associations, gene expression patterns and protein-protein interactions was integrated into a central database. Researchers can select which information for the genes within a candidate interval or for single genes shall be displayed. Genes can also interactively be filtered, sorted and prioritised according to criteria derived from the background knowledge and preconception of the disease under scrutiny. CONCLUSIONS: GeneDistiller provides knowledge-driven, fully interactive and intuitive access to multiple data sources. It displays maximum relevant information, while saving the user from drowning in the flood of data. A typical query takes less than two seconds, thus allowing an interactive and explorative approach to the hunt for the candidate gene. ACCESS: GeneDistiller can be freely accessed at http://www.genedistiller.org.

  4. RANGE: Gene Transfer of Reversibly Controlled Polycistronic Genes

    Directory of Open Access Journals (Sweden)

    Yiwei Chen

    2013-01-01

    Full Text Available We developed a single vector recombinant adeno-associated viral (rAAV expression system for spatial and reversible control of polycistronic gene expression. Our approach (i integrates the advantages of the tetracycline (Tet-controlled transcriptional silencer tTSKid and the self-cleaving 2A peptide bridge, (ii combines essential regulatory components as an autoregulatory loop, (iii simplifies the gene delivery scheme, and (iv regulates multiple genes in a synchronized manner. Controlled by an upstream Tet-responsive element (TRE, both the ubiquitous chicken β-actin promoter (CAG and the neuron-specific synapsin-1 promoter (Syn could regulate expression of tTSKid together with two 2A-linked reporter genes. Transduction in vitro exhibited maximally 50-fold regulation by doxycycline (Dox. Determined by gene delivery method as well as promoter, highly specific tissues were transduced in vivo. Bioluminescence imaging (BLI visualized reversible “ON/OFF” gene switches over repeated “Doxy-Cycling” in living mice. Thus, the reversible rAAV-mediated N-cistronic gene expression system, termed RANGE, may serve as a versatile tool to achieve reversible polycistronic gene regulation for the study of gene function as well as gene therapy.

  5. RANGE: Gene Transfer of Reversibly Controlled Polycistronic Genes.

    Science.gov (United States)

    Chen, Yiwei; Cao, Liji; Luo, Chonglin; Ditzel, Désirée Aw; Peter, Jörg; Sprengel, Rolf

    2013-04-09

    We developed a single vector recombinant adeno-associated viral (rAAV) expression system for spatial and reversible control of polycistronic gene expression. Our approach (i) integrates the advantages of the tetracycline (Tet)-controlled transcriptional silencer tTS(Kid) and the self-cleaving 2A peptide bridge, (ii) combines essential regulatory components as an autoregulatory loop, (iii) simplifies the gene delivery scheme, and (iv) regulates multiple genes in a synchronized manner. Controlled by an upstream Tet-responsive element (TRE), both the ubiquitous chicken β-actin promoter (CAG) and the neuron-specific synapsin-1 promoter (Syn) could regulate expression of tTS(Kid) together with two 2A-linked reporter genes. Transduction in vitro exhibited maximally 50-fold regulation by doxycycline (Dox). Determined by gene delivery method as well as promoter, highly specific tissues were transduced in vivo. Bioluminescence imaging (BLI) visualized reversible "ON/OFF" gene switches over repeated "Doxy-Cycling" in living mice. Thus, the reversible rAAV-mediated N-cistronic gene expression system, termed RANGE, may serve as a versatile tool to achieve reversible polycistronic gene regulation for the study of gene function as well as gene therapy.Molecular Therapy - Nucleic Acids (2013) 2, e85; doi:10.1038/mtna.2013.15; published online 9 April 2013.

  6. Molecular cloning and characterization of a new G-type lysozyme gene (Ec-lysG) in orange-spotted grouper, Epinephelus coioides.

    Science.gov (United States)

    Wei, Shina; Huang, Youhua; Huang, Xiaohong; Cai, Jia; Wei, Jingguang; Li, Pengfei; Ouyang, Zhengliang; Qin, Qiwei

    2014-10-01

    Lysozyme acts as an innate immunity molecule against pathogen infection. In this study, a new G-type lysozyme gene with a typical G-type lysozyme domain (designated as Ec-lysG) was cloned and characterized from the orange-spotted grouper, Epinephelus coioides. The full-length Ec-lysG cDNA contains 1419 bp and encodes a 256-residue protein containing a 25-residue signal peptide at the N-terminus. BLAST analysis reveals Ec-lysG shares 64% identity with Siniperca chuatsi, but 63% to another reported G-type lysozyme from orange-spotted grouper (OSG-lysG). The genomic DNA of Ec-lysG contains four exons and three introns, with a total length of 2062 bp. An amino acid sequence alignment showed that Ec-lysG shares the fundamental structural features of G-type lysozyme, including the catalytic residues, substrate binding sites, and soluble lytic transglycosylase domain. Quantitative PCR showed that Ec-lysG transcript is most abundant in the head kidney, and less abundant in the heart. The expression of Ec-lysG was differentially upregulated in the head kidney after stimulation with lipopolysaccharide, Vibrio alginolyticus, and Singapore grouper iridovirus (SGIV). A subcellular localization analysis showed that Ec-lysG is distributed predominantly in the cytoplasm. Recombinant Ec-lysG (rEc-lysG) has optimal activity at pH 7.5 and 35°C. rEc-lysG showed lytic activities against Gram-positive bacterium Streptococcus iniae, Staphylococcus aureus, and Micrococcus lysodeikticus, and the Gram-negative bacterium V. alginolyticus. Scanning electron microscopy (SEM) showed that rEc-lysG acts on M. lysodeikticus cell walls. The overexpression of Ec-lysG in grouper cells did not significantly delay the occurrence of the cytopathic effect (CPE) induced by SGIV, and did not inhibit viral gene transcription. In conclusion, Ec-lysG might be a potent antibacterial protein, with a role in innate immunity.

  7. Detection and epidemiology of carbapenemase producing Enterobacteriaceae in the Netherlands in 2013-2014.

    Science.gov (United States)

    Vlek, A L M; Frentz, D; Haenen, A; Bootsma, H J; Notermans, D W; Frakking, F N J; de Greeff, S C; Leenstra, T

    2016-07-01

    Laboratory detection of carbapenemase-producing Enterobacteriaceae (CPE) is complicated. Screening with MIC values below clinical breakpoints followed by genotypic confirmation is recommended. We evaluated the application of recommended CPE screening and confirmation methods and provide an overview of CPE epidemiology in E. coli and K. pneumoniae in the Netherlands. Data on E. coli and K. pneumoniae isolates with elevated meropenem (>0.25 mg/L) and/or imipenem (>1 mg/L) MIC values in 2013-2014 were selected from the Infectious Disease Surveillance Information System for Antibiotic Resistance. Laboratories were requested to provide additional results of any confirmatory testing performed. Confirmation of elevated carbapenem MIC values using gradient testing was performed in 59.8 % of eligible isolates. Confirmatory testing showed elevated MIC values in 8 % of E. coli and 32 % of K. pneumoniae isolates. The overall proportion of confirmed non-susceptible E. coli and K. pneumoniae was 0.01 % and 0.16 %, respectively. Genotypic confirmation was performed in 61.0 % of isolates with confirmed elevated carbapenem MIC values. A carbapenemase gene was identified in 47 % of E. coli and 65 % of K. pneumoniae isolates. OXA-48, NDM and KPC were the most frequently found carbapenemase genes. The majority (62 %) of CPE isolates was detected through targeted screening. CPE are a rare finding in the Netherlands. Adherence to the national guideline is suboptimal and differs between laboratories, implying a risk of inadequate CPE detection. Since accurate identification of CPE is the first step in prevention of CPE spread, successful implementation of guidelines for testing and reporting of CPE is essential.

  8. Genes, Children and Pediatricians

    Directory of Open Access Journals (Sweden)

    Joana Correia

    2017-01-01

    Full Text Available A male newborn, presenting hipotonia and posterior parietal bossing, developed, in the first 12 hours of life, refusal to feed and hypoglycaemia. A cranial ultrasound, skull X-ray and CT scan revealed an occipital and parietal fracture with an underlying haematoma and extensive extracranial soft-tissue swelling. He was submitted to surgical drainage. After 24 hours: new intracerebral bleeding. At the age of two-months he presented abnormal skin and sparse kinky hair. Serum copper and caeruloplasmin levels were below the normal range. Molecular diagnosis of Menkes disease was made by the identification of a new mutation in ATP7A gene.

  9. MUTATIONS IN CALMODULIN GENES

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to an isolated polynucleotide encoding at least a part of calmodulin and an isolated polypeptide comprising at least a part of a calmodulin protein, wherein the polynucleotide and the polypeptide comprise at least one mutation associated with a cardiac disorder. The ...... the binding of calmodulin to ryanodine receptor 2 and use of such compound in a treatment of an individual having a cardiac disorder. The invention further provides a kit that can be used to detect specific mutations in calmodulin encoding genes....

  10. MUTATIONS IN CALMODULIN GENES

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to an isolated polynucleotide encoding at least a part of calmodulin and an isolated polypeptide comprising at least a part of a calmodulin protein, wherein the polynucleotide and the polypeptide comprise at least one mutation associated with a cardiac disorder...... the binding of calmodulin to ryanodine receptor 2 and use of such compound in a treatment of an individual having a cardiac disorder. The invention further provides a kit that can be used to detect specific mutations in calmodulin encoding genes....

  11. Genes and Disease: Prader-Willi Syndrome

    Science.gov (United States)

    ... MD): National Center for Biotechnology Information (US); 1998-. Genes and Disease [Internet]. Show details National Center for ... 45K) PDF version of this title (3.8M) Gene sequence Genome view see gene locations Entrez Gene ...

  12. Alcoholism: genes and mechanisms.

    Science.gov (United States)

    Oroszi, Gabor; Goldman, David

    2004-12-01

    Alcoholism is a chronic relapsing/remitting disease that is frequently unrecognized and untreated, in part because of the partial efficacy of treatment. Only approximately one-third of patients remain abstinent and one-third have fully relapsed 1 year after withdrawal from alcohol, with treated patients doing substantially better than untreated [1]. The partial effectiveness of strategies for prevention and treatment, and variation in clinical course and side effects, represent a challenge and an opportunity to better understand the neurobiology of addiction. The strong heritability of alcoholism suggests the existence of inherited functional variants of genes that alter the metabolism of alcohol and variants of other genes that alter the neurobiologies of reward, executive cognitive function, anxiety/dysphoria, and neuronal plasticity. Each of these neurobiologies has been identified as a critical domain in the addictions. Functional alleles that alter alcoholism-related intermediate phenotypes include common alcohol dehydrogenase 1B and aldehyde dehydrogenase 2 variants that cause the aversive flushing reaction; catechol-O-methyltransferase (COMT) Val158Met leading to differences in three aspects of neurobiology: executive cognitive function, stress/anxiety response, and opioid function; opioid receptor micro1 (OPRM1) Asn40Asp, which may serve as a gatekeeper molecule in the action of naltrexone, a drug used in alcoholism treatment; and HTTLPR, which alters serotonin transporter function and appears to affect stress response and anxiety/dysphoria, which are factors relevant to initial vulnerability, the process of addiction, and relapse.

  13. Tetraspanin genes in plants.

    Science.gov (United States)

    Wang, Feng; Vandepoele, Klaas; Van Lijsebettens, Mieke

    2012-07-01

    Tetraspanins represent a four-transmembrane protein superfamily with a conserved structure and amino acid residues that are present in mammals, insects, fungi and plants. Tetraspanins interact with each other or with other membrane proteins to form tetraspanin-enriched microdomains that play important roles in development, pathogenesis and immune responses via facilitating cell-cell adhesion and fusion, ligand binding and intracellular trafficking. Here, we emphasize evolutionary aspects within the plant kingdom based on genomic sequence information. A phylogenetic tree based on 155 tetraspanin genes of 11 plant species revealed ancient and fast evolving clades. Tetraspanins were only present in multicellular plants, were often duplicated in the plant genomes and predicted by the electronic Fluorescent Pictograph for gene expression analysis to be either functionally redundant or divergent. Tetraspanins contain a large extracellular loop with conserved cysteines that provide the binding sites for the interactions. The Arabidopsis thaliana TETRASPANIN1/TORNADO2/EKEKO has a function in leaf and root patterning and TETRASPANIN3 was identified in the plasmodesmatal proteome, suggesting a role in cell-cell communication during plant development.

  14. Improvements to cardiovascular gene ontology.

    Science.gov (United States)

    Lovering, Ruth C; Dimmer, Emily C; Talmud, Philippa J

    2009-07-01

    Gene Ontology (GO) provides a controlled vocabulary to describe the attributes of genes and gene products in any organism. Although one might initially wonder what relevance a 'controlled vocabulary' might have for cardiovascular science, such a resource is proving highly useful for researchers investigating complex cardiovascular disease phenotypes as well as those interpreting results from high-throughput methodologies. GO enables the current functional knowledge of individual genes to be used to annotate genomic or proteomic datasets. In this way, the GO data provides a very effective way of linking biological knowledge with the analysis of the large datasets of post-genomics research. Consequently, users of high-throughput methodologies such as expression arrays or proteomics will be the main beneficiaries of such annotation sets. However, as GO annotations increase in quality and quantity, groups using small-scale approaches will gradually begin to benefit too. For example, genome wide association scans for coronary heart disease are identifying novel genes, with previously unknown connections to cardiovascular processes, and the comprehensive annotation of these novel genes might provide clues to their cardiovascular link. At least 4000 genes, to date, have been implicated in cardiovascular processes and an initiative is underway to focus on annotating these genes for the benefit of the cardiovascular community. In this article we review the current uses of Gene Ontology annotation to highlight why Gene Ontology should be of interest to all those involved in cardiovascular research.

  15. Chromatin analysis of occluded genes

    Science.gov (United States)

    Lee, Jae Hyun; Gaetz, Jedidiah; Bugarija, Branimir; Fernandes, Croydon J.; Snyder, Gregory E.; Bush, Eliot C.; Lahn, Bruce T.

    2009-01-01

    We recently described two opposing states of transcriptional competency. One is termed ‘competent’ whereby a gene is capable of responding to trans-acting transcription factors of the cell, such that it is active if appropriate transcriptional activators are present, though it can also be silent if activators are absent or repressors are present. The other is termed ‘occluded’ whereby a gene is silenced by cis-acting, chromatin-based mechanisms in a manner that blocks it from responding to trans-acting factors, such that it is silent even when activators are present in the cellular milieu. We proposed that gene occlusion is a mechanism by which differentiated cells stably maintain their phenotypic identities. Here, we describe chromatin analysis of occluded genes. We found that DNA methylation plays a causal role in maintaining occlusion for a subset of occluded genes. We further examined a variety of other chromatin marks typically associated with transcriptional silencing, including histone variants, covalent histone modifications and chromatin-associated proteins. Surprisingly, we found that although many of these marks are robustly linked to silent genes (which include both occluded genes and genes that are competent but silent), none is linked specifically to occluded genes. Although the observation does not rule out a possible causal role of these chromatin marks in occlusion, it does suggest that these marks might be secondary effect rather than primary cause of the silent state in many genes. PMID:19380460

  16. Identification of genes and gene products necessary for bacterial bioluminescence.

    OpenAIRE

    Engebrecht, J; Silverman, M.

    1984-01-01

    Expression of luminescence in Escherichia coli was recently achieved by cloning genes from the marine bacterium Vibrio fischeri. One DNA fragment on a hybrid plasmid encoded regulatory functions and enzymatic activities necessary for light production. We report the results of a genetic analysis to identify the luminescence genes (lux) that reside on this recombinant plasmid. lux gene mutations were generated by hydroxylamine treatment, and these mutations were ordered on a linear map by compl...

  17. GENE MUTATIONS, GENETIC DISEASE AND PHARMACOGENETIC GENES DISORDER

    OpenAIRE

    Ishak

    2010-01-01

    Somatic cell mutation is able to create genetic variance in a cell population and can induce cancer and tumor when gene mutations took place at repressor gene in controlling cell cycles such as p53 gene. Whereas germline cell mutation can cause genetic disease such as sickle cell anemia, breast cancer, thalassemia, parkinson’s as well as defect of biochemical pathway that influence drug-receptor interaction, which has negative effect and lead to hospitalized of patient. Most of reports mentio...

  18. PROAPOPTOTIC FUNCTION OF FHIT GENE

    Institute of Scientific and Technical Information of China (English)

    QIU Zhe-fu; HAN De-min; ZHANG Luo; ZHANG Wei

    2006-01-01

    Tumor suppressor gene plays an important role in maintaining the homeostasis between cell loss and growth. Fragile in maintaining the homeostasis between cell loss and growth. Fragile histidine triad (FHIT) gene found recently was studied in a deep going way; it becomes the focus as a result of its roleof ep going way; it becomes the focus as a result of its roleof anti-tumor in human various type of tissue. Due to the high efficiency of FHIT gene benefiting the anti-tumor, it is proposed gh efficiency of FHIT gene benefiting the anti-tumor, it is proposed as a candidate of tumor suppressor gene though there are several opposite opinions.several opposite opinions. We stress the summary of some properties of FHIT gene on proapoptosis according to the published data which showed gene on proapoptosis according to the published data which showed the stronger proapoptotic function of FHIT gene; the apoptosis induced by FHIT depends on the expression level and status of ene; the apoptosis induced by FHIT depends on the expression level and status of FHIT; and FHIT gene can alternate the cell cycling properties and reduce the tumorigenic potential; the apoptotic process e can alternate the cell cycling properties and reduce the tumorigenic potential; the apoptotic process induced by FHIT has no relation to p53 gene. In a ward, in consideration of its multiple functions against malignancies, FHIT in consideration of its multiple functions against malignancies, FHIT gene deserves attention and exploration as a selective target for searching the mechanism of tumorigenesis and clinical et for searching the mechanism of tumorigenesis and clinical therapeutic applications in further.le histidine triad (FHIT) gene; Apoptosis; Tumorigenesis; Tumor suppressor gene deserves attention and exploration as a selective target for searching the mechanism of tumorigenesis and clinical therapeutic applications in further.

  19. Regulation of gene expression by Goodwin's loop with many genes

    Science.gov (United States)

    Sielewiesiuk, Jan; Łopaciuk, Agata

    2012-01-01

    The paper presents a simple analysis of a long Goodwin's loop containing many genes. The genes form a closed series. The rate of transcription of any gene is up or down regulated by theprotein product of the preceding gene. We describe the loop with a system of ordinary differential equations of order s. Oscillatory solutions of the system are possible at the odd number of repressions and any number of inductions if the product of all Hill's coefficients, related to both repressions and inductions, is larger than:

  20. Gene: a gene-centered information resource at NCBI.

    Science.gov (United States)

    Brown, Garth R; Hem, Vichet; Katz, Kenneth S; Ovetsky, Michael; Wallin, Craig; Ermolaeva, Olga; Tolstoy, Igor; Tatusova, Tatiana; Pruitt, Kim D; Maglott, Donna R; Murphy, Terence D

    2015-01-01

    The National Center for Biotechnology Information's (NCBI) Gene database (www.ncbi.nlm.nih.gov/gene) integrates gene-specific information from multiple data sources. NCBI Reference Sequence (RefSeq) genomes for viruses, prokaryotes and eukaryotes are the primary foundation for Gene records in that they form the critical association between sequence and a tracked gene upon which additional functional and descriptive content is anchored. Additional content is integrated based on the genomic location and RefSeq transcript and protein sequence data. The content of a Gene record represents the integration of curation and automated processing from RefSeq, collaborating model organism databases, consortia such as Gene Ontology, and other databases within NCBI. Records in Gene are assigned unique, tracked integers as identifiers. The content (citations, nomenclature, genomic location, gene products and their attributes, phenotypes, sequences, interactions, variation details, maps, expression, homologs, protein domains and external databases) is available via interactive browsing through NCBI's Entrez system, via NCBI's Entrez programming utilities (E-Utilities and Entrez Direct) and for bulk transfer by FTP.

  1. Gene expression analysis identifies global gene dosage sensitivity in cancer

    DEFF Research Database (Denmark)

    Fehrmann, Rudolf S. N.; Karjalainen, Juha M.; Krajewska, Malgorzata;

    2015-01-01

    expression. We reanalyzed 77,840 expression profiles and observed a limited set of 'transcriptional components' that describe well-known biology, explain the vast majority of variation in gene expression and enable us to predict the biological function of genes. On correcting expression profiles...... for these components, we observed that the residual expression levels (in 'functional genomic mRNA' profiling) correlated strongly with copy number. DNA copy number correlated positively with expression levels for 99% of all abundantly expressed human genes, indicating global gene dosage sensitivity. By applying...

  2. PDMAEMA based gene delivery materials

    Directory of Open Access Journals (Sweden)

    Seema Agarwal

    2012-09-01

    Full Text Available Gene transfection is the transfer of genetic material like DNA into cells. Cationic polymers which form nanocomplexes with DNA, so-called non-viral gene vectors, are a highly promising platform for efficient gene transfection. Despite intensive research efforts and some of the on-going clinical trials on gene transfection, none of the existing cationic polymer systems are generally acceptable for human gene therapy. Since the process of gene transfection is complex and puts different challenges and demands on the delivery system, there is a strong requirement for the design and development of a multifunctional system in a simple way. This review will discuss recent efforts in design, synthesis, and performance of poly(2-dimethylaminoethyl methacrylate (PDMAEMA nanocomplexes with DNA.

  3. Gene targeting with retroviral vectors

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, J.; Bernstein, A. (Toronto Univ., ON (Canada))

    1989-04-01

    The authors have designed and constructed integration-defective retroviral vectors to explore their potential for gene targeting in mammalian cells. Two nonoverlapping deletion mutants of the bacterial neomycin resistance (neo) gene were used to detect homologous recombination events between viral and chromosomal sequences. Stable neo gene correction events were selected at a frequency of approximately 1 G418/sup r/ cell per 3 x 10/sup 6/ infected cells. Analysis of the functional neo gene in independent targeted cell clones indicated that unintegrated retroviral linear DNA recombined with the target by gene conversion for variable distances into regions of nonhomology. In addition, transient neo gene correction events which were associated with the complete loss of the chromosomal target sequences were observed. These results demonstrated that retroviral vectors can recombine with homologous chromosomal sequences in rodent and human cells.

  4. Brief isoflurane anaesthesia affects differential gene expression, gene ontology and gene networks in rat brain.

    Science.gov (United States)

    Lowes, Damon A; Galley, Helen F; Moura, Alessandro P S; Webster, Nigel R

    2017-01-15

    Much is still unknown about the mechanisms of effects of even brief anaesthesia on the brain and previous studies have simply compared differential expression profiles with and without anaesthesia. We hypothesised that network analysis, in addition to the traditional differential gene expression and ontology analysis, would enable identification of the effects of anaesthesia on interactions between genes. Rats (n=10 per group) were randomised to anaesthesia with isoflurane in oxygen or oxygen only for 15min, and 6h later brains were removed. Differential gene expression and gene ontology analysis of microarray data was performed. Standard clustering techniques and principal component analysis with Bayesian rules were used along with social network analysis methods, to quantitatively model and describe the gene networks. Anaesthesia had marked effects on genes in the brain with differential regulation of 416 probe sets by at least 2 fold. Gene ontology analysis showed 23 genes were functionally related to the anaesthesia and of these, 12 were involved with neurotransmitter release, transport and secretion. Gene network analysis revealed much greater connectivity in genes from brains from anaesthetised rats compared to controls. Other importance measures were also altered after anaesthesia; median [range] closeness centrality (shortest path) was lower in anaesthetized animals (0.07 [0-0.30]) than controls (0.39 [0.30-0.53], pgenes after anaesthesia and suggests future targets for investigation. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. How eukaryotic genes are transcribed

    OpenAIRE

    Venters, Bryan J; Pugh, B. Franklin

    2009-01-01

    Regulation of eukaryotic gene expression is far more complex than one might have imagined thirty years ago. However, progress towards understanding gene regulatory mechanisms has been rapid and comprehensive, which has made the integration of detailed observations into broadly connected concepts a challenge. This review attempts to integrate the following concepts: 1) a well-defined organization of nucleosomes and modification states at most genes, 2) regulatory networks of sequence-specific ...

  6. Gene set analysis for GWAS

    DEFF Research Database (Denmark)

    Debrabant, Birgit; Soerensen, Mette

    2014-01-01

    Abstract We discuss the use of modified Kolmogorov-Smirnov (KS) statistics in the context of gene set analysis and review corresponding null and alternative hypotheses. Especially, we show that, when enhancing the impact of highly significant genes in the calculation of the test statistic...... parameter and the genesis and distribution of the gene-level statistics, and illustrate the effects of differential weighting in a real-life example....

  7. Gene and genome parameters of mammalian liver circadian genes (LCGs.

    Directory of Open Access Journals (Sweden)

    Gang Wu

    Full Text Available The mammalian circadian system controls various physiology processes and behavior responses by regulating thousands of circadian genes with rhythmic expressions. In this study, we redefined circadian-regulated genes based on published results in the mouse liver and compared them with other gene groups defined relative to circadian regulations, especially the non-circadian-regulated genes expressed in liver at multiple molecular levels from gene position to protein expression based on integrative analyses of different datasets from the literature. Based on the intra-tissue analysis, the liver circadian genes or LCGs show unique features when compared to other gene groups. First, LCGs in general have less neighboring genes and larger in both genomic and 3'-UTR lengths but shorter in CDS (coding sequence lengths. Second, LCGs have higher mRNA and protein abundance, higher temporal expression variations, and shorter mRNA half-life. Third, more than 60% of LCGs form major co-expression clusters centered in four temporal windows: dawn, day, dusk, and night. In addition, larger and smaller LCGs are found mainly expressed in the day and night temporal windows, respectively, and we believe that LCGs are well-partitioned into the gene expression regulatory network that takes advantage of gene size, expression constraint, and chromosomal architecture. Based on inter-tissue analysis, more than half of LCGs are ubiquitously expressed in multiple tissues but only show rhythmical expression in one or limited number of tissues. LCGs show at least three-fold lower expression variations across the temporal windows than those among different tissues, and this observation suggests that temporal expression variations regulated by the circadian system is relatively subtle as compared with the tissue expression variations formed during development. Taken together, we suggest that the circadian system selects gene parameters in a cost effective way to improve tissue

  8. Testing for gene-gene interaction with AMMI models.

    Science.gov (United States)

    Barhdadi, Amina; Dubé, Marie-Pierre

    2010-01-01

    Studies have shown that many common diseases are influenced by multiple genes and their interactions. There is currently a strong interest in testing for association between combinations of these genes and disease, in particular because genes that affect the risk of disease only in the presence of another genetic variant may not be detected in marginal analysis. In this paper we propose the use of additive main effect and multiplicative interaction (AMMI) models to detect and to quantify gene-gene interaction effects for a quantitative trait. The objective of the present research is to demonstrate the practical advantages of these models to describe complex interaction between two unlinked loci. Although gene-gene interactions have often been defined as a deviance from additive genetic effects, the residual term has generally not been appropriately treated. The AMMI models allow for the analysis of a two way factorial data structure and combine the analysis of variance of the two main genotype effects with a principal component analysis of the residual multiplicative interaction. The AMMI models for gene-gene interaction presented here allow for the testing of non additivity between the two loci, and also describe how their interaction structure fits the existing non-additivity. Moreover, these models can be used to identify the specific two genotypes combinations that contribute to the significant gene-gene interaction. We describe the use of the biplot to display the structure of the interaction and evaluate the performance of the AMMI and the special cases of the AMMI previously described by Tukey and Mandel with simulated data sets. Our simulated study showed that the AMMI model is as powerful as general linear models when the interaction is not modeled in the presence of marginal effects. However, in the presence of pure epitasis, i.e. in the absence of marginal effects, the AMMI method was not found to be superior to other tested regression methods.

  9. Introduction: Cancer Gene Networks.

    Science.gov (United States)

    Clarke, Robert

    2017-01-01

    Constructing, evaluating, and interpreting gene networks generally sits within the broader field of systems biology, which continues to emerge rapidly, particular with respect to its application to understanding the complexity of signaling in the context of cancer biology. For the purposes of this volume, we take a broad definition of systems biology. Considering an organism or disease within an organism as a system, systems biology is the study of the integrated and coordinated interactions of the network(s) of genes, their variants both natural and mutated (e.g., polymorphisms, rearrangements, alternate splicing, mutations), their proteins and isoforms, and the organic and inorganic molecules with which they interact, to execute the biochemical reactions (e.g., as enzymes, substrates, products) that reflect the function of that system. Central to systems biology, and perhaps the only approach that can effectively manage the complexity of such systems, is the building of quantitative multiscale predictive models. The predictions of the models can vary substantially depending on the nature of the model and its inputoutput relationships. For example, a model may predict the outcome of a specific molecular reaction(s), a cellular phenotype (e.g., alive, dead, growth arrest, proliferation, and motility), a change in the respective prevalence of cell or subpopulations, a patient or patient subgroup outcome(s). Such models necessarily require computers. Computational modeling can be thought of as using machine learning and related tools to integrate the very high dimensional data generated from modern, high throughput omics technologies including genomics (next generation sequencing), transcriptomics (gene expression microarrays; RNAseq), metabolomics and proteomics (ultra high performance liquid chromatography, mass spectrometry), and "subomic" technologies to study the kinome, methylome, and others. Mathematical modeling can be thought of as the use of ordinary

  10. Genes, evolution and intelligence.

    Science.gov (United States)

    Bouchard, Thomas J

    2014-11-01

    I argue that the g factor meets the fundamental criteria of a scientific construct more fully than any other conception of intelligence. I briefly discuss the evidence regarding the relationship of brain size to intelligence. A review of a large body of evidence demonstrates that there is a g factor in a wide range of species and that, in the species studied, it relates to brain size and is heritable. These findings suggest that many species have evolved a general-purpose mechanism (a general biological intelligence) for dealing with the environments in which they evolved. In spite of numerous studies with considerable statistical power, we know of very few genes that influence g and the effects are very small. Nevertheless, g appears to be highly polygenic. Given the complexity of the human brain, it is not surprising that that one of its primary faculties-intelligence-is best explained by the near infinitesimal model of quantitative genetics.

  11. Gene-environment interaction.

    Science.gov (United States)

    Manuck, Stephen B; McCaffery, Jeanne M

    2014-01-01

    With the advent of increasingly accessible technologies for typing genetic variation, studies of gene-environment (G×E) interactions have proliferated in psychological research. Among the aims of such studies are testing developmental hypotheses and models of the etiology of behavioral disorders, defining boundaries of genetic and environmental influences, and identifying individuals most susceptible to risk exposures or most amenable to preventive and therapeutic interventions. This research also coincides with the emergence of unanticipated difficulties in detecting genetic variants of direct association with behavioral traits and disorders, which may be obscured if genetic effects are expressed only in predisposing environments. In this essay we consider these and other rationales for positing G×E interactions, review conceptual models meant to inform G×E interpretations from a psychological perspective, discuss points of common critique to which G×E research is vulnerable, and address the role of the environment in G×E interactions.

  12. Angiogenin gene polymorphism

    Institute of Scientific and Technical Information of China (English)

    Hongli Wang; Dongsheng Fan; Yingshuang Zhang

    2013-01-01

    Angiogenin is associated with the pathogenesis of diabetic peripheral neuropathy. Here, we se-quenced the coding region of the angiogenin gene in genomic DNA from 207 patients with type 2 diabetes mel itus (129 diabetic peripheral neuropathy patients and 78 diabetic non-neuropathy pa-tients) and 268 healthy controls. Al subjects were from the Han population of northern China. No mutations were found. We then compared the genotype and allele frequencies of the angiogenin synonymous single nucleotide polymorphism rs11701 between the diabetic peripheral neuropathy patients and controls, and between the diabetic neuropathy and non-neuropathy patients, using a case-control design. We detected no statistical y significant genetic associations. Angiogenin may not be associated with genetic susceptibility to diabetic peripheral neuropathy in the Han population of northern China.

  13. Gene therapy in the cornea.

    Science.gov (United States)

    Mohan, Rajiv R; Sharma, Ajay; Netto, Marcelo V; Sinha, Sunilima; Wilson, Steven E

    2005-09-01

    Technological advances in the field of gene therapy has prompted more than three hundred phase I and phase II gene-based clinical trials for the treatment of cancer, AIDS, macular degeneration, cardiovascular, and other monogenic diseases. Besides treating diseases, gene transfer technology has been utilized for the development of preventive and therapeutic vaccines for malaria, tuberculosis, hepatitis A, B and C viruses, AIDS, and influenza. The potential therapeutic applications of gene transfer technology are enormous. The cornea is an excellent candidate for gene therapy because of its accessibility and immune-privileged nature. In the last two decades, various viral vectors, such as adeno, adeno-associated, retro, lenti, and herpes simplex, as well as non-viral methods, were examined for introducing DNA into corneal cells in vitro, in vivo and ex vivo. Most of these studies used fluorescent or non-fluorescent marker genes to track the level and duration of transgene expression in corneal cells. However, limited studies were directed to evaluate prospects of gene-based interventions for corneal diseases or disorders such as allograft rejection, laser-induced post-operative haze, herpes simplex keratitis, and wound healing in animal models. We will review the successes and obstacles impeding gene therapy approaches used for delivering genes into the cornea.

  14. Are TMEM genes potential candidate genes for panic disorder?

    DEFF Research Database (Denmark)

    Gregersen, Noomi O; Buttenschøn, Henriette Nørmølle; Hedemand, Anne

    2014-01-01

    We analysed single nucleotide polymorphisms in two transmembrane genes (TMEM98 and TMEM132E) in panic disorder (PD) patients and control individuals from the Faroe Islands, Denmark and Germany. The genes encode single-pass membrane proteins and are located within chromosome 17q11.2-q12...

  15. Gene-gene Interaction Analyses for Atrial Fibrillation

    NARCIS (Netherlands)

    Lin, Honghuang; Mueller-Nurasyid, Martina; Smith, Albert V; Arking, Dan E; Barnard, John; Bartz, Traci M; Lunetta, Kathryn L; Lohman, Kurt; Kleber, Marcus E; Lubitz, Steven A; Geelhoed, Bastiaan; Trompet, Stella; Niemeijer, Maartje N; Kacprowski, Tim; Chasman, Daniel I; Klarin, Derek; Sinner, Moritz F; Waldenberger, Melanie; Meitinger, Thomas; Harris, Tamara B; Launer, Lenore J; Soliman, Elsayed Z; Chen, Lin Y; Smith, Jonathan D; Van Wagoner, David R; Rotter, Jerome I; Psaty, Bruce M; Xie, Zhijun; Hendricks, Audrey E; Ding, Jingzhong; Delgado, Graciela E; Verweij, Niek; van der Harst, Pim; Macfarlane, Peter W; Ford, Ian; Hofman, Albert; Uitterlinden, André; Heeringa, Jan; Franco, Oscar H; Kors, Jan A; Weiss, Stefan; Völzke, Henry; Rose, Lynda M; Natarajan, Pradeep; Kathiresan, Sekar; Kääb, Stefan; Gudnason, Vilmundur; Alonso, Alvaro; Chung, Mina K; Heckbert, Susan R; Benjamin, Emelia J; Liu, Yongmei; März, Winfried; Rienstra, Michiel; Jukema, J Wouter; Stricker, Bruno H; Dörr, Marcus; Albert, Christine M; Ellinor, Patrick T

    2016-01-01

    Atrial fibrillation (AF) is a heritable disease that affects more than thirty million individuals worldwide. Extensive efforts have been devoted to the study of genetic determinants of AF. The objective of our study is to examine the effect of gene-gene interaction on AF susceptibility. We performed

  16. Gene-gene Interaction Analyses for Atrial Fibrillation

    NARCIS (Netherlands)

    H. Lin (Honghuang); M. Mueller-Nurasyid; A.V. Smith (Albert Vernon); D.E. Arking (Dan); J. Barnard (John); T.M. Bartz (Traci M.); K.L. Lunetta (Kathryn); K. Lohman (Kurt); M.E. Kleber (Marcus); S.A. Lubitz (Steven); Geelhoed, B. (Bastiaan); S. Trompet (Stella); M.N. Niemeijer (Maartje); T. Kacprowski (Tim); D.I. Chasman (Daniel); Klarin, D. (Derek); M.F. Sinner (Moritz); M. Waldenberger (Melanie); T. Meitinger (Thomas); T.B. Harris (Tamara); Launer, L.J. (Lenore J.); E.Z. Soliman (Elsayed Z.); L. Chen (Lin); J.D. Smith (Jonathan); D.R. van Wagoner (David); Rotter, J.I. (Jerome I.); B.M. Psaty (Bruce); Xie, Z. (Zhijun); A.E. Hendricks (Audrey E.); Ding, J. (Jingzhong); G.E. Delgado (Graciela E.); N. Verweij (Niek); P. van der Harst (Pim); P.W. MacFarlane (Peter); I. Ford (Ian); A. Hofman (Albert); A.G. Uitterlinden (André); J. Heeringa (Jan); O.H. Franco (Oscar); J.A. Kors (Jan); Weiss, S. (Stefan); H. Völzke (Henry); L.M. Rose (Lynda); Natarajan, P. (Pradeep); S. Kathiresan (Sekar); S. Kääb (Stefan); V. Gudnason (Vilmundur); A. Alonso (Alvaro); M.K. Chung (Mina); S.R. Heckbert (Susan); E.J. Benjamin (Emelia); Y. Liu (Yongmei); W. März (Winfried); S.A. Rienstra; J.W. Jukema (Jan Wouter); B.H.Ch. Stricker (Bruno); M. Dörr (Marcus); C.M. Albert (Christine); P.T. Ellinor (Patrick)

    2016-01-01

    textabstractAtrial fibrillation (AF) is a heritable disease that affects more than thirty million individuals worldwide. Extensive efforts have been devoted to the study of genetic determinants of AF. The objective of our study is to examine the effect of gene-gene interaction on AF susceptibility.

  17. Classifying genes to the correct Gene Ontology Slim term in Saccharomyces cerevisiae using neighbouring genes with classification learning

    Directory of Open Access Journals (Sweden)

    Tsatsoulis Costas

    2010-05-01

    Full Text Available Abstract Background There is increasing evidence that gene location and surrounding genes influence the functionality of genes in the eukaryotic genome. Knowing the Gene Ontology Slim terms associated with a gene gives us insight into a gene's functionality by informing us how its gene product behaves in a cellular context using three different ontologies: molecular function, biological process, and cellular component. In this study, we analyzed if we could classify a gene in Saccharomyces cerevisiae to its correct Gene Ontology Slim term using information about its location in the genome and information from its nearest-neighbouring genes using classification learning. Results We performed experiments to establish that the MultiBoostAB algorithm using the J48 classifier could correctly classify Gene Ontology Slim terms of a gene given information regarding the gene's location and information from its nearest-neighbouring genes for training. Different neighbourhood sizes were examined to determine how many nearest neighbours should be included around each gene to provide better classification rules. Our results show that by just incorporating neighbour information from each gene's two-nearest neighbours, the percentage of correctly classified genes to their correct Gene Ontology Slim term for each ontology reaches over 80% with high accuracy (reflected in F-measures over 0.80 of the classification rules produced. Conclusions We confirmed that in classifying genes to their correct Gene Ontology Slim term, the inclusion of neighbour information from those genes is beneficial. Knowing the location of a gene and the Gene Ontology Slim information from neighbouring genes gives us insight into that gene's functionality. This benefit is seen by just including information from a gene's two-nearest neighbouring genes.

  18. Classifying genes to the correct Gene Ontology Slim term in Saccharomyces cerevisiae using neighbouring genes with classification learning.

    Science.gov (United States)

    Amthauer, Heather A; Tsatsoulis, Costas

    2010-05-28

    There is increasing evidence that gene location and surrounding genes influence the functionality of genes in the eukaryotic genome. Knowing the Gene Ontology Slim terms associated with a gene gives us insight into a gene's functionality by informing us how its gene product behaves in a cellular context using three different ontologies: molecular function, biological process, and cellular component. In this study, we analyzed if we could classify a gene in Saccharomyces cerevisiae to its correct Gene Ontology Slim term using information about its location in the genome and information from its nearest-neighbouring genes using classification learning. We performed experiments to establish that the MultiBoostAB algorithm using the J48 classifier could correctly classify Gene Ontology Slim terms of a gene given information regarding the gene's location and information from its nearest-neighbouring genes for training. Different neighbourhood sizes were examined to determine how many nearest neighbours should be included around each gene to provide better classification rules. Our results show that by just incorporating neighbour information from each gene's two-nearest neighbours, the percentage of correctly classified genes to their correct Gene Ontology Slim term for each ontology reaches over 80% with high accuracy (reflected in F-measures over 0.80) of the classification rules produced. We confirmed that in classifying genes to their correct Gene Ontology Slim term, the inclusion of neighbour information from those genes is beneficial. Knowing the location of a gene and the Gene Ontology Slim information from neighbouring genes gives us insight into that gene's functionality. This benefit is seen by just including information from a gene's two-nearest neighbouring genes.

  19. On meme--gene coevolution.

    Science.gov (United States)

    Bull, L; Holland, O; Blackmore, S

    2000-01-01

    In this article we examine the effects of the emergence of a new replicator, memes, on the evolution of a pre-existing replicator, genes. Using a version of the NKCS model we examine the effects of increasing the rate of meme evolution in relation to the rate of gene evolution, for various degrees of interdependence between the two replicators. That is, the effects of memes' (suggested) more rapid rate of evolution in comparison to that of genes is investigated using a tunable model of coevolution. It is found that, for almost any degree of interdependence between the two replicators, as the rate of meme evolution increases, a phase transition-like dynamic occurs under which memes have a significantly detrimental effect on the evolution of genes, quickly resulting in the cessation of effective gene evolution. Conversely, the memes experience a sharp increase in benefit from increasing their rate of evolution. We then examine the effects of enabling genes to reduce the percentage of gene-detrimental evolutionary steps taken by memes. Here a critical region emerges as the comparative rate of meme evolution increases, such that if genes cannot effectively select memes a high percentage of the time, they suffer from meme evolution as if they had almost no selective capability.

  20. Susceptibility Genes in Thyroid Autoimmunity

    Directory of Open Access Journals (Sweden)

    Yoshiyuki Ban

    2005-01-01

    Full Text Available The autoimmune thyroid diseases (AITD are complex diseases which are caused by an interaction between susceptibility genes and environmental triggers. Genetic susceptibility in combination with external factors (e.g. dietary iodine is believed to initiate the autoimmune response to thyroid antigens. Abundant epidemiological data, including family and twin studies, point to a strong genetic influence on the development of AITD. Various techniques have been employed to identify the genes contributing to the etiology of AITD, including candidate gene analysis and whole genome screening. These studies have enabled the identification of several loci (genetic regions that are linked with AITD, and in some of these loci, putative AITD susceptibility genes have been identified. Some of these genes/loci are unique to Graves' disease (GD and Hashimoto's thyroiditis (HT and some are common to both the diseases, indicating that there is a shared genetic susceptibility to GD and HT. The putative GD and HT susceptibility genes include both immune modifying genes (e.g. HLA, CTLA-4 and thyroid specific genes (e.g. TSHR, Tg. Most likely, these loci interact and their interactions may influence disease phenotype and severity.

  1. The flow of gene expression.

    Science.gov (United States)

    Misteli, Tom

    2004-03-01

    Gene expression is a highly interconnected multistep process. A recent meeting in Iguazu Falls, Argentina, highlighted the need to uncover both the molecular details of each single step as well as the mechanisms of coordination among processes in order to fully understand the expression of genes.

  2. Phytochrome-regulated Gene Expression

    Institute of Scientific and Technical Information of China (English)

    Peter H. Quail

    2007-01-01

    Identification of all genes involved in the phytochrome (phy)-mediated responses of plants to their light environment is an important goal in providing an overall understanding of light-regulated growth and development. This article highlights and integrates the central findings of two recent comprehensive studies in Arabidopsis that have identified the genome-wide set of phy-regulated genes that respond rapidly to red-light signals upon first exposure of dark-grown seedlings, and have tested the functional relevance to normal seedling photomorphogenesis of an initial subset of these genes. The data: (a) reveal considerable complexity in the channeling of the light signals through the different phy-family members (phyA to phyE) to responsive genes; (b) identify a diversity of transcription-factor-encoding genes as major early, if not primary, targets of phy signaling, and, therefore, as potentially important regulators in the transcriptional-network hierarchy; and (c) identify auxin-related genes as the dominant class among rapidly-regulated, hormone-related genes. However, reverse-genetic functional profiling of a selected subset of these genes reveals that only a limited fraction are necessary for optimal phy-induced seedling deetiolation.

  3. Candidate genes for behavioural ecology

    NARCIS (Netherlands)

    Fitzpatrick, M.J.; Ben-Sahar, Y.; Smid, H.M.; Vet, L.E.M.; Robinson, G.E.; Sokolowski, M.B.

    2005-01-01

    In spite of millions of years of evolutionary divergence, the conservation of gene function is common across distant lineages. As such, genes that are known to influence behaviour in one organism are likely to influence similar behaviours in other organisms. Recent studies of the evolution of behavi

  4. Candidate gene prioritization with Endeavour.

    Science.gov (United States)

    Tranchevent, Léon-Charles; Ardeshirdavani, Amin; ElShal, Sarah; Alcaide, Daniel; Aerts, Jan; Auboeuf, Didier; Moreau, Yves

    2016-07-08

    Genomic studies and high-throughput experiments often produce large lists of candidate genes among which only a small fraction are truly relevant to the disease, phenotype or biological process of interest. Gene prioritization tackles this problem by ranking candidate genes by profiling candidates across multiple genomic data sources and integrating this heterogeneous information into a global ranking. We describe an extended version of our gene prioritization method, Endeavour, now available for six species and integrating 75 data sources. The performance (Area Under the Curve) of Endeavour on cross-validation benchmarks using 'gold standard' gene sets varies from 88% (for human phenotypes) to 95% (for worm gene function). In addition, we have also validated our approach using a time-stamped benchmark derived from the Human Phenotype Ontology, which provides a setting close to prospective validation. With this benchmark, using 3854 novel gene-phenotype associations, we observe a performance of 82%. Altogether, our results indicate that this extended version of Endeavour efficiently prioritizes candidate genes. The Endeavour web server is freely available at https://endeavour.esat.kuleuven.be/.

  5. Determining Semantically Related Significant Genes.

    Science.gov (United States)

    Taha, Kamal

    2014-01-01

    GO relation embodies some aspects of existence dependency. If GO term xis existence-dependent on GO term y, the presence of y implies the presence of x. Therefore, the genes annotated with the function of the GO term y are usually functionally and semantically related to the genes annotated with the function of the GO term x. A large number of gene set enrichment analysis methods have been developed in recent years for analyzing gene sets enrichment. However, most of these methods overlook the structural dependencies between GO terms in GO graph by not considering the concept of existence dependency. We propose in this paper a biological search engine called RSGSearch that identifies enriched sets of genes annotated with different functions using the concept of existence dependency. We observe that GO term xcannot be existence-dependent on GO term y, if x- and y- have the same specificity (biological characteristics). After encoding into a numeric format the contributions of GO terms annotating target genes to the semantics of their lowest common ancestors (LCAs), RSGSearch uses microarray experiment to identify the most significant LCA that annotates the result genes. We evaluated RSGSearch experimentally and compared it with five gene set enrichment systems. Results showed marked improvement.

  6. Nonviral Vectors for Gene Delivery

    Science.gov (United States)

    Baoum, Abdulgader Ahmed

    2011-12-01

    The development of nonviral vectors for safe and efficient gene delivery has been gaining considerable attention recently. An ideal nonviral vector must protect the gene against degradation by nuclease in the extracellular matrix, internalize the plasma membrane, escape from the endosomal compartment, unpackage the gene at some point and have no detrimental effects. In comparison to viruses, nonviral vectors are relatively easy to synthesize, less immunogenic, low in cost, and have no limitation in the size of a gene that can be delivered. Significant progress has been made in the basic science and applications of various nonviral gene delivery vectors; however, the majority of nonviral approaches are still inefficient and often toxic. To this end, two nonviral gene delivery systems using either biodegradable poly(D,L-lactide- co-glycolide) (PLG) nanoparticles or cell penetrating peptide (CPP) complexes have been designed and studied using A549 human lung epithelial cells. PLG nanoparticles were optimized for gene delivery by varying particle surface chemistry using different coating materials that adsorb to the particle surface during formation. A variety of cationic coating materials were studied and compared to more conventional surfactants used for PLG nanoparticle fabrication. Nanoparticles (˜200 nm) efficiently encapsulated plasmids encoding for luciferase (80-90%) and slowly released the same for two weeks. After a delay, moderate levels of gene expression appeared at day 5 for certain positively charged PLG particles and gene expression was maintained for at least two weeks. In contrast, gene expression mediated by polyethyleneimine (PEI) ended at day 5. PLG particles were also significantly less cytotoxic than PEI suggesting the use of these vehicles for localized, sustained gene delivery to the pulmonary epithelium. On the other hand, a more simple method to synthesize 50-200 nm complexes capable of high transfection efficiency or high gene knockdown was

  7. Delivery systems for gene therapy

    Directory of Open Access Journals (Sweden)

    Shrikant Mali

    2013-01-01

    Full Text Available The structure of DNA was unraveled by Watson and Crick in 1953, and two decades later Arber, Nathans and Smith discovered DNA restriction enzymes, which led to the rapid growth in the field of recombinant DNA technology. From expressing cloned genes in bacteria to expressing foreign DNA in transgenic animals, DNA is now slated to be used as a therapeutic agent to replace defective genes in patients suffering from genetic disorders or to kill tumor cells in cancer patients. Gene therapy provides modern medicine with new perspectives that were unthinkable two decades ago. Progress in molecular biology and especially, molecular medicine is now changing the basics of clinical medicine. A variety of viral and non-viral possibilities are available for basic and clinical research. This review summarizes the delivery routes and methods for gene transfer used in gene therapy.

  8. Function analysis of unknown genes

    DEFF Research Database (Denmark)

    Rogowska-Wrzesinska, A.

    2002-01-01

      This thesis entitled "Function analysis of unknown genes" presents the use of proteome analysis for the characterisation of yeast (Saccharomyces cerevisiae) genes and their products (proteins especially those of unknown function). This study illustrates that proteome analysis can be used...... to describe different aspects of molecular biology of the cell, to study changes that occur in the cell due to overexpression or deletion of a gene and to identify various protein modifications. The biological questions and the results of the described studies show the diversity of the information that can...... genes and proteins. It reports the first global proteome database collecting 36 yeast single gene deletion mutants and selecting over 650 differences between analysed mutants and the wild type strain. The obtained results show that two-dimensional gel electrophoresis and mass spectrometry based proteome...

  9. Nanoparticles for retinal gene therapy.

    Science.gov (United States)

    Conley, Shannon M; Naash, Muna I

    2010-09-01

    Ocular gene therapy is becoming a well-established field. Viral gene therapies for the treatment of Leber's congentinal amaurosis (LCA) are in clinical trials, and many other gene therapy approaches are being rapidly developed for application to diverse ophthalmic pathologies. Of late, development of non-viral gene therapies has been an area of intense focus and one technology, polymer-compacted DNA nanoparticles, is especially promising. However, development of pharmaceutically and clinically viable therapeutics depends not only on having an effective and safe vector but also on a practical treatment strategy. Inherited retinal pathologies are caused by mutations in over 220 genes, some of which contain over 200 individual disease-causing mutations, which are individually very rare. This review will focus on both the progress and future of nanoparticles and also on what will be required to make them relevant ocular pharmaceutics. Copyright 2010 Elsevier Ltd. All rights reserved.

  10. Gene targeting in malaria parasites.

    Science.gov (United States)

    Ménard, R; Janse, C

    1997-10-01

    Gene targeting, which permits alteration of a chosen gene in a predetermined way by homologous recombination, is an emerging technology in malaria research. Soon after the development of techniques for stable transformation of red blood cell stages of Plasmodium falciparum and Plasmodium berghei, genes of interest were disrupted in the two species. The main limitations of gene targeting in malaria parasites result from the intracellular growth and slow replication of these parasites. On the other hand, the technology is facilitated by the very high rate of homologous recombination following transformation with targeting constructs (approximately 100%). Here, we describe (i) the vector design and the type of mutation that may be generated in a target locus, (ii) the selection and screening strategies that can be used to identify clones with the desired modification, and (iii) the protocol that was used for disrupting the circumsporozoite protein (CS) and thrombospondin-related anonymous protein (TRAP) genes of P. berghei.

  11. Gene expression profiling: can we identify the right target genes?

    Directory of Open Access Journals (Sweden)

    J. E. Loyd

    2008-12-01

    Full Text Available Gene expression profiling allows the simultaneous monitoring of the transcriptional behaviour of thousands of genes, which may potentially be involved in disease development. Several studies have been performed in idiopathic pulmonary fibrosis (IPF, which aim to define genetic links to the disease in an attempt to improve the current understanding of the underlying pathogenesis of the disease and target pathways for intervention. Expression profiling has shown a clear difference in gene expression between IPF and normal lung tissue, and has identified a wide range of candidate genes, including those known to encode for proteins involved in extracellular matrix formation and degradation, growth factors and chemokines. Recently, familial pulmonary fibrosis cohorts have been examined in an attempt to detect specific genetic mutations associated with IPF. To date, these studies have identified families in which IPF is associated with mutations in the gene encoding surfactant protein C, or with mutations in genes encoding components of telomerase. Although rare and clearly not responsible for the disease in all individuals, the nature of these mutations highlight the importance of the alveolar epithelium in disease pathogenesis and demonstrate the potential for gene expression profiling in helping to advance the current understanding of idiopathic pulmonary fibrosis.

  12. Genes, Economics, and Happiness *

    Science.gov (United States)

    De Neve, Jan-Emmanuel; Christakis, Nicholas A.; Fowler, James H.; Frey, Bruno S.

    2012-01-01

    We explore the influence of genetic variation on subjective well-being by employing a twin design and genetic association study. In a nationally-representative twin sample, we first show that about 33% of the variation in life satisfaction is explained by genetic variation. Although previous studies have shown that baseline happiness is significantly heritable, little research has considered molecular genetic associations with subjective well-being. We study the relationship between a functional polymorphism on the serotonin transporter gene (5-HTTLPR) and life satisfaction. We initially find that individuals with the longer, transcriptionally more efficient variant of this genotype report greater life satisfaction (n=2,545, p=0.012). However, our replication attempts on independent samples produce mixed results indicating that more work needs to be done to better understand the relationship between this genotype and subjective well-being. This work has implications for how economists think about the determinants of utility, and the extent to which exogenous shocks might affect individual well-being. PMID:24349601

  13. Genes, Economics, and Happiness.

    Science.gov (United States)

    De Neve, Jan-Emmanuel; Christakis, Nicholas A; Fowler, James H; Frey, Bruno S

    2012-11-01

    We explore the influence of genetic variation on subjective well-being by employing a twin design and genetic association study. In a nationally-representative twin sample, we first show that about 33% of the variation in life satisfaction is explained by genetic variation. Although previous studies have shown that baseline happiness is significantly heritable, little research has considered molecular genetic associations with subjective well-being. We study the relationship between a functional polymorphism on the serotonin transporter gene (5-HTTLPR) and life satisfaction. We initially find that individuals with the longer, transcriptionally more efficient variant of this genotype report greater life satisfaction (n=2,545, p=0.012). However, our replication attempts on independent samples produce mixed results indicating that more work needs to be done to better understand the relationship between this genotype and subjective well-being. This work has implications for how economists think about the determinants of utility, and the extent to which exogenous shocks might affect individual well-being.

  14. Gene Prediction Using Multinomial Probit Regression with Bayesian Gene Selection

    Directory of Open Access Journals (Sweden)

    Xiaodong Wang

    2004-01-01

    Full Text Available A critical issue for the construction of genetic regulatory networks is the identification of network topology from data. In the context of deterministic and probabilistic Boolean networks, as well as their extension to multilevel quantization, this issue is related to the more general problem of expression prediction in which we want to find small subsets of genes to be used as predictors of target genes. Given some maximum number of predictors to be used, a full search of all possible predictor sets is combinatorially prohibitive except for small predictors sets, and even then, may require supercomputing. Hence, suboptimal approaches to finding predictor sets and network topologies are desirable. This paper considers Bayesian variable selection for prediction using a multinomial probit regression model with data augmentation to turn the multinomial problem into a sequence of smoothing problems. There are multiple regression equations and we want to select the same strongest genes for all regression equations to constitute a target predictor set or, in the context of a genetic network, the dependency set for the target. The probit regressor is approximated as a linear combination of the genes and a Gibbs sampler is employed to find the strongest genes. Numerical techniques to speed up the computation are discussed. After finding the strongest genes, we predict the target gene based on the strongest genes, with the coefficient of determination being used to measure predictor accuracy. Using malignant melanoma microarray data, we compare two predictor models, the estimated probit regressors themselves and the optimal full-logic predictor based on the selected strongest genes, and we compare these to optimal prediction without feature selection.

  15. Therapeutic genes for anti-HIV/AIDS gene therapy.

    Science.gov (United States)

    Bovolenta, Chiara; Porcellini, Simona; Alberici, Luca

    2013-01-01

    The multiple therapeutic approaches developed so far to cope HIV-1 infection, such as anti-retroviral drugs, germicides and several attempts of therapeutic vaccination have provided significant amelioration in terms of life-quality and survival rate of AIDS patients. Nevertheless, no approach has demonstrated efficacy in eradicating this lethal, if untreated, infection. The curative power of gene therapy has been proven for the treatment of monogenic immunodeficiensies, where permanent gene modification of host cells is sufficient to correct the defect for life-time. No doubt, a similar concept is not applicable for gene therapy of infectious immunodeficiensies as AIDS, where there is not a single gene to be corrected; rather engineered cells must gain immunotherapeutic or antiviral features to grant either short- or long-term efficacy mostly by acquisition of antiviral genes or payloads. Anti-HIV/AIDS gene therapy is one of the most promising strategy, although challenging, to eradicate HIV-1 infection. In fact, genetic modification of hematopoietic stem cells with one or multiple therapeutic genes is expected to originate blood cell progenies resistant to viral infection and thereby able to prevail on infected unprotected cells. Ultimately, protected cells will re-establish a functional immune system able to control HIV-1 replication. More than hundred gene therapy clinical trials against AIDS employing different viral vectors and transgenes have been approved or are currently ongoing worldwide. This review will overview anti-HIV-1 infection gene therapy field evaluating strength and weakness of the transgenes and payloads used in the past and of those potentially exploitable in the future.

  16. Progress of gene targeting in mouse

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Gene targeting is a powerful approach of study- ing the genefunction in vivo. Specific genetic modifications, including simple gene disruption, point mutations, large chromosomal deletions and rearrangements, targeted incor- poration of foreign genes, could be introduced into the mouse genome by gene targeting. Recent studies make it possible to do the gene targeting with temporal and spatial control.

  17. Human Lacrimal Gland Gene Expression

    Science.gov (United States)

    Aakalu, Vinay Kumar; Parameswaran, Sowmya; Maienschein-Cline, Mark; Bahroos, Neil; Shah, Dhara; Ali, Marwan; Krishnakumar, Subramanian

    2017-01-01

    Background The study of human lacrimal gland biology and development is limited. Lacrimal gland tissue is damaged or poorly functional in a number of disease states including dry eye disease. Development of cell based therapies for lacrimal gland diseases requires a better understanding of the gene expression and signaling pathways in lacrimal gland. Differential gene expression analysis between lacrimal gland and other embryologically similar tissues may be helpful in furthering our understanding of lacrimal gland development. Methods We performed global gene expression analysis of human lacrimal gland tissue using Affymetrix ® gene expression arrays. Primary data from our laboratory was compared with datasets available in the NLM GEO database for other surface ectodermal tissues including salivary gland, skin, conjunctiva and corneal epithelium. Results The analysis revealed statistically significant difference in the gene expression of lacrimal gland tissue compared to other ectodermal tissues. The lacrimal gland specific, cell surface secretory protein encoding genes and critical signaling pathways which distinguish lacrimal gland from other ectodermal tissues are described. Conclusions Differential gene expression in human lacrimal gland compared with other ectodermal tissue types revealed interesting patterns which may serve as the basis for future studies in directed differentiation among other areas. PMID:28081151

  18. Comprehensive resource: Skeletal gene database.

    Science.gov (United States)

    Jia, L; Ho, N C; Park, S S; Powell, J; Francomano, C A

    2001-01-01

    The Skeletal Gene Database (SGD) is an integrated resource that provides comprehensive information about bone-related genes, mRNA, and proteins expressed in human and mouse, with rich links to numerous other electronic tools. SGD contains expressed sequence tag (EST) data from all the skeletal-related cDNA libraries that are available to the public. It supplies the query/data access analytic tools for users to search and compare each gene expressed in skeletal tissue(s). The results derived from EST tissue expression profiling will allow users to get the data on the mRNA copy numbers of each gene expressed in each tissue and its normalized value. From the SGD, researchers can obtain information regarding the name, symbol, size, exon/intron number, chromosomal location, LocusLink, and related disease (if any is known) of each gene. This electronic compendium also furnishes information on the protein of the corresponding gene including the protein size (amino acid number and molecular weight). It provides swift and ready access to other useful databases including OMIM, UniGene and PUBMED. The data will be updated regularly in step with current and future research, thereby providing what we hope will serve as a highly useful source of information and a powerful analytic tool to the scientific community.

  19. GENES IN SPORT AND DOPING

    Directory of Open Access Journals (Sweden)

    Andrzej Pokrywka

    2013-06-01

    Full Text Available Genes control biological processes such as muscle production of energy, mitochondria biogenesis, bone formation erythropoiesis, angiogenesis, vasodilation, neurogenesis, etc. DNA profiling for athletes reveals genetic variations that may be associated with endurance ability, muscle performance and power exercise, tendon susceptibility to injuries and psychological aptitude. Already, over 200 genes relating to physical performance have been identified by several research groups. Athletes’ genotyping is developing as a tool for the formulation of personalized training and nutritional programmes to optimize sport training as well as for the prediction of exercise-related injuries. On the other hand, development of molecular technology and gene therapy creates a risk of non-therapeutic use of cells, genes and genetic elements to improve athletic performance. Therefore, the World Anti-Doping Agency decided to include prohibition of gene doping within their World Anti-Doping Code in 2003. In this review article, we will provide a current overview of genes for use in athletes’ genotyping and gene doping possibilities, including their development and detection techniques.

  20. Approaches for skeletal gene therapy.

    Science.gov (United States)

    Niyibizi, Christopher; Wallach, Corey J; Mi, Zhibao; Robbins, Paul D

    2002-01-01

    The role of gene therapy in the treatment of musculoskeletal disorders continues to be an active area of research. As the etiology of many musculoskeletal diseases becomes increasingly understood, advances in cellular and gene therapy maybe applied to their potential treatment This review focuses on current investigational strategies to treat osteogenesis imperfecta (OI). OI is a varied group of genetic disorders that result in the diminished integrity of connective tissues as a result of alterations in the genes that encode for either the pro alpha1 or pro alpha2 component of type I collagen. Because most forms of OI result from dominant negative mutations, isolated gene replacement therapy is not a logical treatment option. The combined use of genetic manipulation and cellular transplantation, however, may provide a means to overcome this obstacle. This article describes the recent laboratory and clinical advances in cell therapy, highlights potential techniques being investigated to suppress the expression of the mutant allele with antisense gene therapy, and attempts to deliver collagen genes to bone cells. The challenges that the investigators face in their quest for the skeletal gene therapy are also discussed.

  1. Linking Genes to Cardiovascular Diseases: Gene Action and Gene-Environment Interactions.

    Science.gov (United States)

    Pasipoularides, Ares

    2015-12-01

    A unique myocardial characteristic is its ability to grow/remodel in order to adapt; this is determined partly by genes and partly by the environment and the milieu intérieur. In the "post-genomic" era, a need is emerging to elucidate the physiologic functions of myocardial genes, as well as potential adaptive and maladaptive modulations induced by environmental/epigenetic factors. Genome sequencing and analysis advances have become exponential lately, with escalation of our knowledge concerning sometimes controversial genetic underpinnings of cardiovascular diseases. Current technologies can identify candidate genes variously involved in diverse normal/abnormal morphomechanical phenotypes, and offer insights into multiple genetic factors implicated in complex cardiovascular syndromes. The expression profiles of thousands of genes are regularly ascertained under diverse conditions. Global analyses of gene expression levels are useful for cataloging genes and correlated phenotypes, and for elucidating the role of genes in maladies. Comparative expression of gene networks coupled to complex disorders can contribute insights as to how "modifier genes" influence the expressed phenotypes. Increasingly, a more comprehensive and detailed systematic understanding of genetic abnormalities underlying, for example, various genetic cardiomyopathies is emerging. Implementing genomic findings in cardiology practice may well lead directly to better diagnosing and therapeutics. There is currently evolving a strong appreciation for the value of studying gene anomalies, and doing so in a non-disjointed, cohesive manner. However, it is challenging for many-practitioners and investigators-to comprehend, interpret, and utilize the clinically increasingly accessible and affordable cardiovascular genomics studies. This survey addresses the need for fundamental understanding in this vital area.

  2. Viral vectors for gene transfer: current status of gene therapeutics.

    Science.gov (United States)

    Heilbronn, Regine; Weger, Stefan

    2010-01-01

    Gene therapy for the correction of inherited or acquired disease has gained increasing importance in recent years. Successful treatment of children suffering from severe combined immunodeficiency (SCID) was achieved using retrovirus vectors for gene transfer. Encouraging improvements of vision were reported in a genetic eye disorder (LCA) leading to early childhood blindness. Adeno-associated virus (AAV) vectors were used for gene transfer in these trials. This chapter gives an overview of the design and delivery of viral vectors for the transport of a therapeutic gene into a target cell or tissue. The construction and production of retrovirus, lentivirus, and AAV vectors are covered. The focus is on production methods suitable for biopharmaceutical upscaling and for downstream processing. Quality control measures and biological safety considerations for the use of vectors in clinical trials are discussed.

  3. [Pathogenicity and pneumococcal capsular genes].

    Science.gov (United States)

    García, E; García, P; López, R

    1994-01-01

    Pneumococci remain to be one of the most prominent human pathogens. Increasing efforts are being dedicated to the development of improved vaccines with wider specificity. Since a clear understanding of the genetics of capsular types in Streptococcus pneumoniae is missing, our efforts are oriented to characterize, at the molecular level, the genes involved in capsular polysaccharide biosynthesis. We have cloned and sequenced a chromosomal DNA fragment of a clinical isolate of type 3 pneumococcus and showed that it contains a type 3 specific gene as well as genes common to other serotypes.

  4. Panspermia and horizontal gene transfer

    Science.gov (United States)

    Klyce, Brig

    2009-08-01

    Evidence that extremophiles are hardy and ubiquitous is helping to make panspermia a respectable theory. But even if life on Earth originally came from space, biologists assume that the subsequent evolution of life is still governed by the darwinian paradigm. In this review we show how panspermia could amend darwinism and point to a cosmic source for, not only extremophiles but, all of life. This version of panspermia can be called "strong panspermia." To support this theory we will discuss recent evidence pertaining to horizontal gene transfer, viruses, genes apparently older than the Earthly evolution of the features they encode, and primate-specific genes without identifiable precursors.

  5. An archaeal CRISPR type III-B system exhibiting distinctive RNA targeting features and mediating dual RNA and DNA interference

    DEFF Research Database (Denmark)

    Peng, Wenfang; Feng, Mingxia; Feng, Xu;

    2015-01-01

    CRISPR-Cas systems provide a small RNA-based mechanism to defend against invasive genetic elements in archaea and bacteria. To investigate the in vivo mechanism of RNA interference by two type III-B systems (Cmr-α and Cmr-β) in Sulfolobus islandicus, a genetic assay was developed using plasmids...... carrying an artificial mini-CRISPR (AC) locus with a single spacer. After pAC plasmids were introduced into different strains, Northern analyses confirmed that mature crRNAs were produced from the plasmid-borne CRISPR loci, which then guided gene silencing to target gene expression. Spacer mutagenesis....... islandicus Cmr-α mediated transcription-dependent DNA interference, the Cmr-α constitutes the first CRISPR system exhibiting dual targeting of RNA and DNA....

  6. An archaeal CRISPR type III-B system exhibiting distinctive RNA targeting features and mediating dual RNA and DNA interference

    DEFF Research Database (Denmark)

    Peng, Wenfang; Feng, Mingxia; Feng, Xu

    2015-01-01

    CRISPR-Cas systems provide a small RNA-based mechanism to defend against invasive genetic elements in archaea and bacteria. To investigate the in vivo mechanism of RNA interference by two type III-B systems (Cmr-α and Cmr-β) in Sulfolobus islandicus, a genetic assay was developed using plasmids...... carrying an artificial mini-CRISPR (AC) locus with a single spacer. After pAC plasmids were introduced into different strains, Northern analyses confirmed that mature crRNAs were produced from the plasmid-borne CRISPR loci, which then guided gene silencing to target gene expression. Spacer mutagenesis....... islandicus Cmr-α mediated transcription-dependent DNA interference, the Cmr-α constitutes the first CRISPR system exhibiting dual targeting of RNA and DNA....

  7. First environmental sample containing plasmid-mediated colistin-resistant ESBL-producing Escherichia coli detected in Norway.

    Science.gov (United States)

    Jørgensen, Silje Bakken; Søraas, Arne; Arnesen, Lotte Stenfors; Leegaard, Truls; Sundsfjord, Arnfinn; Jenum, Pål A

    2017-09-01

    We hereby report the detection of the plasmid borne mcr-1 gene conferring colistin resistance in an extended-spectrum β-lactamase (ESBL) producing Escherichia coli ST10 strain retrieved from seawater at a public beach in Norway. The sample was collected in September 2010 and was investigated by whole-genome sequencing in 2016. This report illustrates that E. coli strains carrying plasmid-mediated colistin resistance genes have also reached areas where this drug is hardly used at all. Surveillance of colistin resistance in environmental, veterinary, and human strains is warranted also in countries where colistin resistance is rare in clinical settings. © 2017 APMIS. Published by John Wiley & Sons Ltd.

  8. The Gene Ontology (GO) project in 2006

    National Research Council Canada - National Science Library

    2006-01-01

    The Gene Ontology (GO) project (http://www.geneontology.org) develops and uses a set of structured, controlled vocabularies for community use in annotating genes, gene products and sequences (also see http://song.sourceforge.net...

  9. The Gene Ontology project in 2008

    National Research Council Canada - National Science Library

    The Gene Ontology (GO) project (http://www.geneontology.org/) provides a set of structured, controlled vocabularies for community use in annotating genes, gene products and sequences (also see http://www.sequenceontology.org...

  10. Integrating Gene Ontology and Blast to predict gene functions

    Institute of Scientific and Technical Information of China (English)

    WANG Cheng-gang; MO Zhi-hong

    2007-01-01

    A GoBlast system was built to predict gene function by integrating Blast search and Gene Ontology (GO) annotations together. The operation system was based on Debian Linux 3.1, with Apache as the web server and Mysql database as the data storage system. FASTA files with GO annotations were taken as the sequence source for blast alignment, which were formatted by wu-formatdb program. The GoBlast system includes three Bioperl modules in Perl: a data input module, a data process module and a data output module. A GoBlast query starts with an amino acid or nucleotide sequence. It ends with an output in an html page, presenting high scoring gene products which are of a high homology to the queried sequence and listing associated GO terms beside respective gene poducts. A simple click on a GO term leads to the detailed explanation of the specific gene function. This avails gene function prediction by Blast. GoBlast can be a very useful tool for functional genome research and is available for free at http://bioq.org/goblast.

  11. Gene function prediction based on the Gene Ontology hierarchical structure.

    Science.gov (United States)

    Cheng, Liangxi; Lin, Hongfei; Hu, Yuncui; Wang, Jian; Yang, Zhihao

    2014-01-01

    The information of the Gene Ontology annotation is helpful in the explanation of life science phenomena, and can provide great support for the research of the biomedical field. The use of the Gene Ontology is gradually affecting the way people store and understand bioinformatic data. To facilitate the prediction of gene functions with the aid of text mining methods and existing resources, we transform it into a multi-label top-down classification problem and develop a method that uses the hierarchical relationships in the Gene Ontology structure to relieve the quantitative imbalance of positive and negative training samples. Meanwhile the method enhances the discriminating ability of classifiers by retaining and highlighting the key training samples. Additionally, the top-down classifier based on a tree structure takes the relationship of target classes into consideration and thus solves the incompatibility between the classification results and the Gene Ontology structure. Our experiment on the Gene Ontology annotation corpus achieves an F-value performance of 50.7% (precision: 52.7% recall: 48.9%). The experimental results demonstrate that when the size of training set is small, it can be expanded via topological propagation of associated documents between the parent and child nodes in the tree structure. The top-down classification model applies to the set of texts in an ontology structure or with a hierarchical relationship.

  12. How eukaryotic genes are transcribed.

    Science.gov (United States)

    Venters, Bryan J; Pugh, B Franklin

    2009-06-01

    Regulation of eukaryotic gene expression is far more complex than one might have imagined 30 years ago. However, progress towards understanding gene regulatory mechanisms has been rapid and comprehensive, which has made the integration of detailed observations into broadly connected concepts a challenge. This review attempts to integrate the following concepts: (1) a well-defined organization of nucleosomes and modification states at most genes; (2) regulatory networks of sequence-specific transcription factors; (3) chromatin remodeling coupled to promoter assembly of the general transcription factors and RNA polymerase II; and (4) phosphorylation states of RNA polymerase II coupled to chromatin modification states during transcription. The wealth of new insights arising from the tools of biochemistry, genomics, cell biology, and genetics is providing a remarkable view into the mechanics of gene regulation.

  13. Gene Variants Reduce Opioid Risks

    Science.gov (United States)

    ... Opioids Prescription Drugs & Cold Medicines Steroids (Anabolic) Synthetic Cannabinoids (K2/Spice) Synthetic Cathinones (Bath Salts) Tobacco/Nicotine ... variant of the gene for the μ-opioid receptor (OPRM1) with a decreased risk for addiction to ...

  14. Gene therapy in ocular diseases

    Directory of Open Access Journals (Sweden)

    Singh Vijay

    2002-01-01

    Full Text Available Gene therapy is a novel form of drug delivery that enlists the synthetic machinery of the patient′s cells to produce a therapeutic agent. Genes may be delivered into cells in vitro or in vivo utilising viral or non-viral vectors. Recent technical advances have led to the demonstration of the molecular basis of various ocular diseases. Ocular disorders with the greatest potential for benefit of gene therapy include hereditary diseases such as retinitis pigmentosa, tumours such as retinoblastoma or melanoma, and acquired proliferative and neovascular retinal disorders. Gene transfer into ocular tissues has been demonstrated with growing functional success and may develop into a new therapeutic tool for clinical ophthalmology in future.

  15. Plant gene technology: social considerations

    African Journals Online (AJOL)

    Administrator

    African Journal of Biotechnology Vol. 3 (3), pp. 156-158 ... The genetic modification of plants by gene technology is of immense potential benefits, but there may ... this modern age. ... advantages over the current rate of food production and.

  16. Genes That Influence Blood Pressure

    Science.gov (United States)

    ... Influence Blood Pressure Gene Linked to Optimism and Self-Esteem Designing New Diabetes Drugs Connect with Us Subscribe to get NIH Research Matters by email RSS Feed Facebook Email us Mailing Address: NIH Research Matters Bldg. ...

  17. MADS-box gene evolution - structure and transcription patterns

    DEFF Research Database (Denmark)

    Johansen, Bo; Pedersen, Louise Buchholt; Skipper, Martin;

    2002-01-01

    Mads-box genes, ABC model, Evolution, Phylogeny, Transcription patterns, Gene structure, Conserved motifs......Mads-box genes, ABC model, Evolution, Phylogeny, Transcription patterns, Gene structure, Conserved motifs...

  18. The evolution of resistance gene in plants

    Institute of Scientific and Technical Information of China (English)

    BEN Haiyan; LIU Xuemin; LI Lijun; LIU Li

    2007-01-01

    Resistance genes enable plants to fight against plant pathogens. Plant resistance genes (R gene) are organized complexly in genome. Some resistance gene sequence data enable an insight into R gene structure and gene evolution. Some sites like Leucine-Rich Repeat (LRR) are of specific interest since homologous recombination can happen. Crossing over, transposon insertion and excision and mutation can produce new specificity. Three models explaining R gene evolution were discussed. More information needed for dissection of R gene evolution though some step can be inferred from genetic and sequence analysis.

  19. The Insect SNMP Gene Family

    Science.gov (United States)

    2009-01-01

    B 1 ( b o v ) Clade 3 - SNMPs Clade 2 Clade 1 CD36 Insect (Holometabola) CD36 Gene family Holometabola Phylogeny (11 Orders) Tribolium castaneum...melanogaster genes (see Nichols and Vogt, 2008). Bootstrap support (1000 replicates) is indicated for the major clades. B. Phylogeny of holometabolous...A. aegypti eggs were graciously provided by Mark Brown (University of Georgia, Department of Entomology) and raised on a larval diet (pond fish food

  20. Rice's Salt Tolerance Gene Cloned

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ In cooperation with US colleagues, CAS researchers have made significant progress in their studies into functional genes for key agronomic traits by cloning SKC1, a salt-tolerant functional gene of rice and making clear its biological functions and mechanisms. This pioneering work,which was reported in the Oct. issue of Nature Genetics (37:1141-1146), is believed to hold promise to increase the output of the crop plant in this country.

  1. Genes de defensa en plantas

    OpenAIRE

    Carbonero Zalduegui, Pilar; García Olmedo, Francisco

    1994-01-01

    Se revisan los avances realizados en la caracterización de los genes que codifican para ciertas familias de proteínas vegetales que son tóxicas o inhibitorias frente a insectos, hongos y bacterias. La caracterización incluye el estudio in vitro de las propiedades de las proteínas purificadas y la experimentación in vivo con plantas transgénicas que expresan los genes correspondientes.

  2. Gene mutations in hepatocellular adenomas

    DEFF Research Database (Denmark)

    Raft, Marie B; Jørgensen, Ernö N; Vainer, Ben

    2015-01-01

    is associated with bi-allelic mutations in the TCF1 gene and morphologically has marked steatosis. β-catenin activating HCA has increased activity of the Wnt/β-catenin pathway and is associated with possible malignant transformation. Inflammatory HCA is characterized by an oncogene-induced inflammation due....... This review offers an overview of the reported gene mutations associated with hepatocellular adenomas together with a discussion of the diagnostic and prognostic value....

  3. Routine active surveillance for carbapenemase-producing Enterobacteriaceae from rectal swabs: diagnostic implications of multiplex polymerase chain reaction.

    Science.gov (United States)

    Lowman, W; Marais, M; Ahmed, K; Marcus, L

    2014-10-01

    Screening for carriage of carbapenemase-producing Enterobacteriaceae (CPE) is considered an important infection prevention and control strategy. To date, screening has relied primarily on culture although polymerase chain reaction (PCR)-based screening is gaining momentum. Currently there is no gold standard screening method and consequently it is important to consider the implications of different diagnostic strategies used in active surveillance. To assess the utility of a multiplex PCR screening strategy, as a component of active surveillance, for detection of CPE in patients admitted to various hospitals. A single rectal swab was collected from patients at various hospitals, considered to be at risk of colonization with CPE. Comparison of a modified US Centers for Disease Control and Prevention culture protocol with a PCR-based assay for the detection of the blaNDM, blaKPC, blaOxA-48-like, blaVIM, blaIMP, and blaGES genes was performed. Of the 251 consecutive rectal swabs collected, 30 were PCR positive for one or more carbapenemase genes. Fifteen (50%) were culture positive and CPE only accounted for six isolates. PCR demonstrated excellent sensitivity (100%), specificity (89.8%), and negative predictive value (100%) for detection of CPE, but a positive predictive value of only 46.6% and 16.6% for detection of carbapenemase-producing Gram-negatives and CPE, respectively. The apparent excellent performance characteristics of PCR for detection of CPE from rectal swabs must be tempered by knowledge of CPE prevalence and be interpreted within a defined epidemiological context. Further comparative research with culture, evaluating the clinical utility of PCR-based assays as a screening tool, is needed. Copyright © 2014 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  4. Immunoglobulin genes of the turtles.

    Science.gov (United States)

    Magadán-Mompó, Susana; Sánchez-Espinel, Christian; Gambón-Deza, Francisco

    2013-03-01

    The availability of reptile genomes for the use of the scientific community is an exceptional opportunity to study the evolution of immunoglobulin genes. The genome of Chrysemys picta bellii and Pelodiscus sinensis is the first one that has been reported for turtles. The scanning for immunoglobulin genes resulted in the presence of a complex locus for the immunoglobulin heavy chain (IGH). This IGH locus in both turtles contains genes for 13 isotypes in C. picta bellii and 17 in P. sinensis. These correspond with one immunoglobulin M, one immunoglobulin D, several immunoglobulins Y (six in C. picta bellii and eight in P. sinensis), and several immunoglobulins that are similar to immunoglobulin D2 (five in C. picta belli and seven in P. sinensis) that was previously described in Eublepharis macularius. It is worthy to note that IGHD2 are placed in an inverted transcriptional orientation and present sequences for two immunoglobulin domains that are similar to bird IgA domains. Furthermore, its phylogenetic analysis allows us to consider about the presence of IGHA gene in a primitive reptile, so we would be dealing with the memory of the gene that originated from the bird IGHA. In summary, we provide a clear picture of the immunoglobulins present in a turtle, whose analysis supports the idea that turtles emerged from the evolutionary line from the differentiation of birds and the presence of the IGHA gene present in a common ancestor.

  5. Gene expression in colorectal cancer

    DEFF Research Database (Denmark)

    Birkenkamp-Demtroder, Karin; Christensen, Lise Lotte; Olesen, Sanne Harder

    2002-01-01

    Understanding molecular alterations in colorectal cancer (CRC) is needed to define new biomarkers and treatment targets. We used oligonucleotide microarrays to monitor gene expression of about 6,800 known genes and 35,000 expressed sequence tags (ESTs) on five pools (four to six samples in each p...... with a high frequency of loss of heterozygosity. The genes and ESTs presented in this study encode new potential tumor markers as well as potential novel therapeutic targets for prevention or therapy of CRC.......Understanding molecular alterations in colorectal cancer (CRC) is needed to define new biomarkers and treatment targets. We used oligonucleotide microarrays to monitor gene expression of about 6,800 known genes and 35,000 expressed sequence tags (ESTs) on five pools (four to six samples in each...... pool) of total RNA from left-sided sporadic colorectal carcinomas. We compared normal tissue to carcinoma tissue from Dukes' stages A-D (noninvasive to distant metastasis) and identified 908 known genes and 4,155 ESTs that changed remarkably from normal to tumor tissue. Based on intensive filtering 226...

  6. Gene Polymorphisms in Chronic Periodontitis

    Directory of Open Access Journals (Sweden)

    Marja L. Laine

    2010-01-01

    Full Text Available We aimed to conduct a review of the literature for gene polymorphisms associated with chronic periodontitis (CP susceptibility. A comprehensive search of the literature in English was performed using the keywords: periodontitis, periodontal disease, combined with the words genes, mutation, or polymorphism. Candidate gene polymorphism studies with a case-control design and reported genotype frequencies in CP patients were searched and reviewed. There is growing evidence that polymorphisms in the IL1, IL6, IL10, vitamin D receptor, and CD14 genes may be associated with CP in certain populations. However, carriage rates of the rare (-allele of any polymorphism varied considerably among studies and most of the studies appeared under-powered and did not correct for other risk factors. Larger cohorts, well-defined phenotypes, control for other risk factors, and analysis of multiple genes and polymorphisms within the same pathway are needed to get a more comprehensive insight into the contribution of gene polymorphisms in CP.

  7. Homologous gene replacement in Physarum

    Energy Technology Data Exchange (ETDEWEB)

    Burland, T.G. [Univ. of Wisconsin, Madison, WI (United States); Pallotta, D. [Laval Univ., Quebec (Canada)

    1995-01-01

    The protist Physarum polycephalum is useful for analysis of several aspects of cellular and developmental biology. To expand the opportunities for experimental analysis of this organism, we have developed a method for gene replacement. We transformed Physarum amoebae with plasmid DNA carrying a mutant allele, ardD{Delta}1, of the ardD actin gene; ardD{Delta}1 mutates the critical carboxy-terminal region of the gene product. Because ardD is not expressed in the amoeba, replacement of ardD{sup +} with ardD{Delta}1 should not be lethal for this cell type. Transformants were obtained only when linear plasmid DNA was used. Most transformants carried one copy of ardD{Delta}1 in addition to ardD{sup +}, but in two (5%), ardD{sup +} was replaced by a single copy of ardD{Delta}1. This is the first example of homologous gene replacement in Physarum. ardD{Delta}1 was stably maintained in the genome through growth, development and meiosis. We found no effect of ardD{Delta}l on viability, growth, or development of any of the various cell types of Physarum. Thus, the carboxy-terminal region of the ardD product appears not to perform a unique essential role in growth or development. Nevertheless, this method for homologous gene replacement can be applied to analyze the function of any cloned gene. 38 refs., 6 figs., 1 tab.

  8. Cationic Bolaamphiphiles for Gene Delivery

    Science.gov (United States)

    Tan, Amelia Li Min; Lim, Alisa Xue Ling; Zhu, Yiting; Yang, Yi Yan; Khan, Majad

    2014-05-01

    Advances in medical research have shed light on the genetic cause of many human diseases. Gene therapy is a promising approach which can be used to deliver therapeutic genes to treat genetic diseases at its most fundamental level. In general, nonviral vectors are preferred due to reduced risk of immune response, but they are also commonly associated with low transfection efficiency and high cytotoxicity. In contrast to viral vectors, nonviral vectors do not have a natural mechanism to overcome extra- and intracellular barriers when delivering the therapeutic gene into cell. Hence, its design has been increasingly complex to meet challenges faced in targeting of, penetration of and expression in a specific host cell in achieving more satisfactory transfection efficiency. Flexibility in design of the vector is desirable, to enable a careful and controlled manipulation of its properties and functions. This can be met by the use of bolaamphiphile, a special class of lipid. Unlike conventional lipids, bolaamphiphiles can form asymmetric complexes with the therapeutic gene. The advantage of having an asymmetric complex lies in the different purposes served by the interior and exterior of the complex. More effective gene encapsulation within the interior of the complex can be achieved without triggering greater aggregation of serum proteins with the exterior, potentially overcoming one of the great hurdles faced by conventional single-head cationic lipids. In this review, we will look into the physiochemical considerations as well as the biological aspects of a bolaamphiphile-based gene delivery system.

  9. Origin and evolution of new genes

    Institute of Scientific and Technical Information of China (English)

    LI Xin; YANG Shuang; PENG Lixin; CHEN Hong; WANG Wen

    2004-01-01

    Organisms have variable genome sizes andcontain different numbers of genes. This difference demonstrates that new gene origination is a fundamental process in evolutionary biology. Though the study of the origination of new genes dated back more than half a century ago, it is not until the 1990s when the first young genejingwei was found that empirical investigation of the molecular mechanisms of origination of new genes became possible. In the recent years,several young genes were identified and the studies on these genes have greatly enriched the knowledge of this field. Yet more details in a general picture of new genes origination are to be clarified. We have developed a systematic approach to searching for young genes at the genomic level, in the hope to summarize a general pattern of the origination and evolution of new genes, such as the rate of new gene appearance, impact of new genes on their host genomes, etc.

  10. Aphids acquired symbiotic genes via lateral gene transfer

    Directory of Open Access Journals (Sweden)

    Nakabachi Atsushi

    2009-03-01

    Full Text Available Abstract Background Aphids possess bacteriocytes, which are cells specifically differentiated to harbour the obligate mutualist Buchnera aphidicola (γ-Proteobacteria. Buchnera has lost many of the genes that appear to be essential for bacterial life. From the bacteriocyte of the pea aphid Acyrthosiphon pisum, we previously identified two clusters of expressed sequence tags that display similarity only to bacterial genes. Southern blot analysis demonstrated that they are encoded in the aphid genome. In this study, in order to assess the possibility of lateral gene transfer, we determined the full-length sequences of these transcripts, and performed detailed structural and phylogenetic analyses. We further examined their expression levels in the bacteriocyte using real-time quantitative RT-PCR. Results Sequence similarity searches demonstrated that these fully sequenced transcripts are significantly similar to the bacterial genes ldcA (product, LD-carboxypeptidase and rlpA (product, rare lipoprotein A, respectively. Buchnera lacks these genes, whereas many other bacteria, including Escherichia coli, a close relative of Buchnera, possess both ldcA and rlpA. Molecular phylogenetic analysis clearly demonstrated that the aphid ldcA was derived from a rickettsial bacterium closely related to the extant Wolbachia spp. (α-Proteobacteria, Rickettsiales, which are intracellular symbionts of various lineages of arthropods. The evolutionary origin of rlpA was not fully resolved, but it was clearly demonstrated that its double-ψ β-barrel domain is of bacterial origin. Real-time quantitative RT-PCR demonstrated that ldcA and rlpA are expressed 11.6 and 154-fold higher in the bacteriocyte than in the whole body, respectively. LdcA is an enzyme required for recycling murein (peptidoglycan, which is a component of the bacterial cell wall. As Buchnera possesses a cell wall composed of murein but lacks ldcA, a high level of expression of the aphid ldcA in the

  11. Newer Gene Editing Technologies toward HIV Gene Therapy

    Directory of Open Access Journals (Sweden)

    Premlata Shankar

    2013-11-01

    Full Text Available Despite the great success of highly active antiretroviral therapy (HAART in ameliorating the course of HIV infection, alternative therapeutic approaches are being pursued because of practical problems associated with life-long therapy. The eradication of HIV in the so-called “Berlin patient” who received a bone marrow transplant from a CCR5-negative donor has rekindled interest in genome engineering strategies to achieve the same effect. Precise gene editing within the cells is now a realistic possibility with recent advances in understanding the DNA repair mechanisms, DNA interaction with transcription factors and bacterial defense mechanisms. Within the past few years, four novel technologies have emerged that can be engineered for recognition of specific DNA target sequences to enable site-specific gene editing: Homing Endonuclease, ZFN, TALEN, and CRISPR/Cas9 system. The most recent CRISPR/Cas9 system uses a short stretch of complementary RNA bound to Cas9 nuclease to recognize and cleave target DNA, as opposed to the previous technologies that use DNA binding motifs of either zinc finger proteins or transcription activator-like effector molecules fused to an endonuclease to mediate sequence-specific DNA cleavage. Unlike RNA interference, which requires the continued presence of effector moieties to maintain gene silencing, the newer technologies allow permanent disruption of the targeted gene after a single treatment. Here, we review the applications, limitations and future prospects of novel gene-editing strategies for use as HIV therapy.

  12. Sequencing and Gene Expression Analysis of Leishmania tropica LACK Gene.

    Directory of Open Access Journals (Sweden)

    Nour Hammoudeh

    2014-12-01

    Full Text Available Leishmania Homologue of receptors for Activated C Kinase (LACK antigen is a 36-kDa protein, which provokes a very early immune response against Leishmania infection. There are several reports on the expression of LACK through different life-cycle stages of genus Leishmania, but only a few of them have focused on L.tropica.The present study provides details of the cloning, DNA sequencing and gene expression of LACK in this parasite species. First, several local isolates of Leishmania parasites were typed in our laboratory using PCR technique to verify of Leishmania parasite species. After that, LACK gene was amplified and cloned into a vector for sequencing. Finally, the expression of this molecule in logarithmic and stationary growth phase promastigotes, as well as in amastigotes, was evaluated by Reverse Transcription-PCR (RT-PCR technique.The typing result confirmed that all our local isolates belong to L.tropica. LACK gene sequence was determined and high similarity was observed with the sequences of other Leishmania species. Furthermore, the expression of LACK gene in both promastigotes and amastigotes forms was confirmed.Overall, the data set the stage for future studies of the properties and immune role of LACK gene products.

  13. The biology of novel animal genes: Mouse APEX gene knockout

    Energy Technology Data Exchange (ETDEWEB)

    MacInnes, M.; Altherr, M.R.; Ludwig, D. [Los Alamos National Lab., NM (United States); Pedersen, R.; Mold, C. [Univ. of California, San Francisco, CA (United States)

    1997-07-01

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The controlled breeding of novel genes into mice, including the gene knockout (KO), or conversely by adding back transgenes provide powerful genetic technologies that together suffice to determine in large part the biological role(s) of novel genes. Inbred mouse remains the best understood and most useful mammalian experimental system available for tackling the biology of novel genes. The major mammalian apurinic/apyrimidinic (AP) endonuclease (APE), is involved in a key step in the repair of spontaneous and induced AP sites in DNA. Efficient repair of these lesions is imperative to prevent the stable incorporation of mutations into the cellular genome which may lead to cell death or transformation. Loss or modulation of base excison repair activity in vivo may elevate the spontaneous mutation rate in cells, and may lead to a substantial increase in the incidence of cancer. Despite extensive biochemical analysis, however, the significance of these individual APE functions in vivo has not been elucidated. Mouse embryonic stem (ES) cells heterozygous for a deletion mutation in APE have been generated and whole animals containing the APE mutation have been derived from these ES cells. Animals homozygous for the APE null mutation die early in gestation, underscoring the biological significance of this DNA repair gene.

  14. Newer gene editing technologies toward HIV gene therapy.

    Science.gov (United States)

    Manjunath, N; Yi, Guohua; Dang, Ying; Shankar, Premlata

    2013-11-14

    Despite the great success of highly active antiretroviral therapy (HAART) in ameliorating the course of HIV infection, alternative therapeutic approaches are being pursued because of practical problems associated with life-long therapy. The eradication of HIV in the so-called "Berlin patient" who received a bone marrow transplant from a CCR5-negative donor has rekindled interest in genome engineering strategies to achieve the same effect. Precise gene editing within the cells is now a realistic possibility with recent advances in understanding the DNA repair mechanisms, DNA interaction with transcription factors and bacterial defense mechanisms. Within the past few years, four novel technologies have emerged that can be engineered for recognition of specific DNA target sequences to enable site-specific gene editing: Homing Endonuclease, ZFN, TALEN, and CRISPR/Cas9 system. The most recent CRISPR/Cas9 system uses a short stretch of complementary RNA bound to Cas9 nuclease to recognize and cleave target DNA, as opposed to the previous technologies that use DNA binding motifs of either zinc finger proteins or transcription activator-like effector molecules fused to an endonuclease to mediate sequence-specific DNA cleavage. Unlike RNA interference, which requires the continued presence of effector moieties to maintain gene silencing, the newer technologies allow permanent disruption of the targeted gene after a single treatment. Here, we review the applications, limitations and future prospects of novel gene-editing strategies for use as HIV therapy.

  15. [Developments in gene delivery vectors for ocular gene therapy].

    Science.gov (United States)

    Khabou, Hanen; Dalkara, Deniz

    2015-05-01

    Gene therapy is quickly becoming a reality applicable in the clinic for inherited retinal diseases. Its remarkable success in safety and efficacy, in clinical trials for Leber's congenital amaurosis (LCA) type II generated significant interest and opened up possibilities for a new era of retinal gene therapies. Success in these clinical trials was mainly due to the favorable characteristics of the retina as a target organ. The eye offers several advantages as it is readily accessible and has some degree of immune privilege making it suitable for application of viral vectors. The viral vectors most frequently used for retinal gene delivery are lentivirus, adenovirus and adeno-associated virus (AAV). Here we will discuss the use of these viral vectors in retinal gene delivery with a strong focus on favorable properties of AAV. Thanks to its small size, AAV diffuses well in the inter-neural matrix making it suitable for applications in neural retina. Building on this initial clinical success with LCA II, we have now many opportunities to extend this proof-of-concept to other retinal diseases using AAV as a vector. This article will discuss what are some of the most imminent cellular targets for such therapies and the AAV toolkit that has been built to target these cells successfully. We will also discuss some of the challenges that we face in translating AAV-based gene therapies to the clinic. © 2015 médecine/sciences – Inserm.

  16. Reduced rates of gene loss, gene silencing, and gene mutation in Dnmt1-deficient embryonic stem cells

    NARCIS (Netherlands)

    Chan, M.F.; van Amerongen, R.; Nijjar, T.; Cuppen, E.; Jones, P.A.; Laird, P.W.

    2001-01-01

    Tumor suppressor gene inactivation is a crucial event in oncogenesis. Gene inactivation mechanisms include events resulting in loss of heterozygosity (LOH), gene mutation, and transcriptional silencing. The contribution of each of these different pathways varies among tumor suppressor genes and by c

  17. Characterizing gene-gene interactions in a statistical epistasis network of twelve candidate genes for obesity.

    Science.gov (United States)

    De, Rishika; Hu, Ting; Moore, Jason H; Gilbert-Diamond, Diane

    2015-01-01

    Recent findings have reemphasized the importance of epistasis, or gene-gene interactions, as a contributing factor to the unexplained heritability of obesity. Network-based methods such as statistical epistasis networks (SEN), present an intuitive framework to address the computational challenge of studying pairwise interactions between thousands of genetic variants. In this study, we aimed to analyze pairwise interactions that are associated with Body Mass Index (BMI) between SNPs from twelve genes robustly associated with obesity (BDNF, ETV5, FAIM2, FTO, GNPDA2, KCTD15, MC4R, MTCH2, NEGR1, SEC16B, SH2B1, and TMEM18). We used information gain measures to identify all SNP-SNP interactions among and between these genes that were related to obesity (BMI > 30 kg/m(2)) within the Framingham Heart Study Cohort; interactions exceeding a certain threshold were used to build an SEN. We also quantified whether interactions tend to occur more between SNPs from the same gene (dyadicity) or between SNPs from different genes (heterophilicity). We identified a highly connected SEN of 709 SNPs and 1241 SNP-SNP interactions. Combining the SEN framework with dyadicity and heterophilicity analyses, we found 1 dyadic gene (TMEM18, P-value = 0.047) and 3 heterophilic genes (KCTD15, P-value = 0.045; SH2B1, P-value = 0.003; and TMEM18, P-value = 0.001). We also identified a lncRNA SNP (rs4358154) as a key node within the SEN using multiple network measures. This study presents an analytical framework to characterize the global landscape of genetic interactions from genome-wide arrays and also to discover nodes of potential biological significance within the identified network.

  18. Combining Hierarchical and Associative Gene Ontology Relations with Textual Evidence in Estimating Gene and Gene Product Similarity

    Energy Technology Data Exchange (ETDEWEB)

    Sanfilippo, Antonio P.; Posse, Christian; Gopalan, Banu; Riensche, Roderick M.; Beagley, Nathaniel; Baddeley, Bob L.; Tratz, Stephen C.; Gregory, Michelle L.

    2007-03-01

    Gene and gene product similarity is a fundamental diagnostic measure in analyzing biological data and constructing predictive models for functional genomics. With the rising influence of the Gene Ontology, two complementary approaches have emerged where the similarity between two genes or gene products is obtained by comparing Gene Ontology (GO) annotations associated with the genes or gene products. One approach captures GO-based similarity in terms of hierarchical relations within each gene subontology. The other approach identifies GO-based similarity in terms of associative relations across the three gene subontologies. We propose a novel methodology where the two approaches can be merged with ensuing benefits in coverage and accuracy, and demonstrate that further improvements can be obtained by integrating textual evidence extracted from relevant biomedical literature.

  19. Gene expression profiles in skeletal muscle after gene electrotransfer

    DEFF Research Database (Denmark)

    Hojman, Pernille; Zibert, John R; Gissel, Hanne;

    2007-01-01

    with the control muscles. Most interestingly, no changes in the expression of proteins involved in inflammatory responses or muscle regeneration was detected, indicating limited muscle damage and regeneration. Histological analysis revealed structural changes with loss of cell integrity and striation pattern......BACKGROUND: Gene transfer by electroporation (DNA electrotransfer) to muscle results in high level long term transgenic expression, showing great promise for treatment of e.g. protein deficiency syndromes. However little is known about the effects of DNA electrotransfer on muscle fibres. We have......) followed by a long low voltage pulse (LV, 100 V/cm, 400 ms); a pulse combination optimised for efficient and safe gene transfer. Muscles were transfected with green fluorescent protein (GFP) and excised at 4 hours, 48 hours or 3 weeks after treatment. RESULTS: Differentially expressed genes were...

  20. Imaging reporter gene for monitoring gene therapy; Imagerie par gene rapporteur: un atout pour la therapie genique

    Energy Technology Data Exchange (ETDEWEB)

    Beco, V. de; Baillet, G.; Tamgac, F.; Tofighi, M.; Weinmann, P.; Vergote, J.; Moretti, J.L. [Centre Hospitalier Universitaire Avicenne, Service Central de Medecine Nucleaire et Biophysique, UPRES 2360, 93 - Bobigny (France); Tamgac, G. [Univetsite d' Uludag, Service de Medecine Nucleaire, Bursa (Turkey)

    2002-06-01

    Scintigraphic images can be obtained to document gene function at cellular level. This approach is presented here and the use of a reporter gene to monitor gene therapy is described. Two main ways are presented: either the use of a reporter gene coding for an enzyme the action of which will be monitored by radiolabeled pro-drug, or a cellular receptor gene, the action of which is documented by a radio labeled cognate receptor ligand. (author)

  1. COGNATE: comparative gene annotation characterizer.

    Science.gov (United States)

    Wilbrandt, Jeanne; Misof, Bernhard; Niehuis, Oliver

    2017-07-17

    The comparison of gene and genome structures across species has the potential to reveal major trends of genome evolution. However, such a comparative approach is currently hampered by a lack of standardization (e.g., Elliott TA, Gregory TR, Philos Trans Royal Soc B: Biol Sci 370:20140331, 2015). For example, testing the hypothesis that the total amount of coding sequences is a reliable measure of potential proteome diversity (Wang M, Kurland CG, Caetano-Anollés G, PNAS 108:11954, 2011) requires the application of standardized definitions of coding sequence and genes to create both comparable and comprehensive data sets and corresponding summary statistics. However, such standard definitions either do not exist or are not consistently applied. These circumstances call for a standard at the descriptive level using a minimum of parameters as well as an undeviating use of standardized terms, and for software that infers the required data under these strict definitions. The acquisition of a comprehensive, descriptive, and standardized set of parameters and summary statistics for genome publications and further analyses can thus greatly benefit from the availability of an easy to use standard tool. We developed a new open-source command-line tool, COGNATE (Comparative Gene Annotation Characterizer), which uses a given genome assembly and its annotation of protein-coding genes for a detailed description of the respective gene and genome structure parameters. Additionally, we revised the standard definitions of gene and genome structures and provide the definitions used by COGNATE as a working draft suggestion for further reference. Complete parameter lists and summary statistics are inferred using this set of definitions to allow down-stream analyses and to provide an overview of the genome and gene repertoire characteristics. COGNATE is written in Perl and freely available at the ZFMK homepage ( https://www.zfmk.de/en/COGNATE ) and on github ( https

  2. Analysis of Duplicate Genes in Soybean

    Institute of Scientific and Technical Information of China (English)

    C.M. Cai; K.J. Van; M.Y. Kim; S.H. Lee

    2007-01-01

    @@ Gene duplication is a major determinant of the size and gene complement of eukaryotic genomes (Lockton and Gaut, 2005). There are a number of different ways in which duplicate genes can arise (Sankoff, 2001), but the most spectacular method of gene duplication may be whole genome duplication via polyploidization.

  3. Synthetic promoter libraries- tuning of gene expression

    DEFF Research Database (Denmark)

    Hammer, Karin; Mijakovic, Ivan; Jensen, Peter Ruhdal

    2006-01-01

    The study of gene function often requires changing the expression of a gene and evaluating the consequences. In principle, the expression of any given gene can be modulated in a quasi-continuum of discrete expression levels but the traditional approaches are usually limited to two extremes: gene ...

  4. Deregulated genes in sporadic vestibular schwannomas

    DEFF Research Database (Denmark)

    Cayé-Thomasen, Per; Helweg-Larsen, Rehannah Holga Andrea; Stangerup, Sven-Eric;

    2010-01-01

    In search of genes associated with vestibular schwannoma tumorigenesis, this study examines the gene expression in human vestibular nerve versus vestibular schwannoma tissue samples using microarray technology.......In search of genes associated with vestibular schwannoma tumorigenesis, this study examines the gene expression in human vestibular nerve versus vestibular schwannoma tissue samples using microarray technology....

  5. Deregulated genes in sporadic vestibular schwannomas

    DEFF Research Database (Denmark)

    Cayé-Thomasen, Per; Helweg-Larsen, Rehannah Holga Andrea; Stangerup, Sven-Eric

    2010-01-01

    In search of genes associated with vestibular schwannoma tumorigenesis, this study examines the gene expression in human vestibular nerve versus vestibular schwannoma tissue samples using microarray technology.......In search of genes associated with vestibular schwannoma tumorigenesis, this study examines the gene expression in human vestibular nerve versus vestibular schwannoma tissue samples using microarray technology....

  6. Gene Therapy Applications in Gastroenterology and Hepatology

    Directory of Open Access Journals (Sweden)

    Catherine H Wu

    2000-01-01

    Full Text Available Advantages and disadvantages of viral vectors and nonviral vectors for gene delivery to digestive organs are reviewed. Advances in systems for the introduction of new gene expression are described, including self-deleting retroviral transfer vectors, chimeric viruses and chimeric oligonucleotides. Systems for inhibition of gene expression are discussed, including antisense oligonucleotides, ribozymes and dominant-negative genes.

  7. Using GenePattern for Gene Expression Analysis

    Science.gov (United States)

    Kuehn, Heidi; Liberzon, Arthur; Reich, Michael; Mesirov, Jill P.

    2013-01-01

    The abundance of genomic data now available in biomedical research has stimulated the development of sophisticated statistical methods for interpreting the data, and of special visualization tools for displaying the results in a concise and meaningful manner. However, biologists often find these methods and tools difficult to understand and use correctly. GenePattern is a freely available software package that addresses this issue by providing more than 100 analysis and visualization tools for genomic research in a comprehensive user-friendly environment for users at all levels of computational experience and sophistication. This unit demonstrates how to prepare and analyze microarray data in GenePattern. PMID:18551415

  8. The KCNE genes in hypertrophic cardiomyopathy: a candidate gene study

    DEFF Research Database (Denmark)

    Hedley, Paula L; Haundrup, Ole; Andersen, Paal S

    2011-01-01

    The gene family KCNE1-5, which encode modulating β-subunits of several repolarising K+-ion channels, has been associated with genetic cardiac diseases such as long QT syndrome, atrial fibrillation and Brugada syndrome. The minK peptide, encoded by KCNE1, is attached to the Z-disc of the sarcomere...... as well as the T-tubules of the sarcolemma. It has been suggested that minK forms part of an "electro-mechanical feed-back" which links cardiomyocyte stretching to changes in ion channel function. We examined whether mutations in KCNE genes were associated with hypertrophic cardiomyopathy (HCM), a genetic...

  9. Gene replacement in Penicillium roqueforti.

    Science.gov (United States)

    Goarin, Anne; Silar, Philippe; Malagnac, Fabienne

    2015-05-01

    Most cheese-making filamentous fungi lack suitable molecular tools to improve their biotechnology potential. Penicillium roqueforti, a species of high industrial importance, would benefit from functional data yielded by molecular genetic approaches. This work provides the first example of gene replacement by homologous recombination in P. roqueforti, demonstrating that knockout experiments can be performed in this fungus. To do so, we improved the existing transformation method to integrate transgenes into P. roqueforti genome. In the meantime, we cloned the PrNiaD gene, which encodes a NADPH-dependent nitrate reductase that reduces nitrate to nitrite. Then, we performed a deletion of the PrNiaD gene from P. roqueforti strain AGO. The ΔPrNiaD mutant strain is more resistant to chlorate-containing medium than the wild-type strain, but did not grow on nitrate-containing medium. Because genomic data are now available, we believe that generating selective deletions of candidate genes will be a key step to open the way for a comprehensive exploration of gene function in P. roqueforti.

  10. Gene Ontology Consortium: going forward.

    Science.gov (United States)

    2015-01-01

    The Gene Ontology (GO; http://www.geneontology.org) is a community-based bioinformatics resource that supplies information about gene product function using ontologies to represent biological knowledge. Here we describe improvements and expansions to several branches of the ontology, as well as updates that have allowed us to more efficiently disseminate the GO and capture feedback from the research community. The Gene Ontology Consortium (GOC) has expanded areas of the ontology such as cilia-related terms, cell-cycle terms and multicellular organism processes. We have also implemented new tools for generating ontology terms based on a set of logical rules making use of templates, and we have made efforts to increase our use of logical definitions. The GOC has a new and improved web site summarizing new developments and documentation, serving as a portal to GO data. Users can perform GO enrichment analysis, and search the GO for terms, annotations to gene products, and associated metadata across multiple species using the all-new AmiGO 2 browser. We encourage and welcome the input of the research community in all biological areas in our continued effort to improve the Gene Ontology. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  11. Gene Ontology Consortium: going forward

    Science.gov (United States)

    2015-01-01

    The Gene Ontology (GO; http://www.geneontology.org) is a community-based bioinformatics resource that supplies information about gene product function using ontologies to represent biological knowledge. Here we describe improvements and expansions to several branches of the ontology, as well as updates that have allowed us to more efficiently disseminate the GO and capture feedback from the research community. The Gene Ontology Consortium (GOC) has expanded areas of the ontology such as cilia-related terms, cell-cycle terms and multicellular organism processes. We have also implemented new tools for generating ontology terms based on a set of logical rules making use of templates, and we have made efforts to increase our use of logical definitions. The GOC has a new and improved web site summarizing new developments and documentation, serving as a portal to GO data. Users can perform GO enrichment analysis, and search the GO for terms, annotations to gene products, and associated metadata across multiple species using the all-new AmiGO 2 browser. We encourage and welcome the input of the research community in all biological areas in our continued effort to improve the Gene Ontology. PMID:25428369

  12. Clock Genes in Glia Cells

    Science.gov (United States)

    Chi-Castañeda, Donají

    2016-01-01

    Circadian rhythms are periodic patterns in biological processes that allow the organisms to anticipate changes in the environment. These rhythms are driven by the suprachiasmatic nucleus (SCN), the master circadian clock in vertebrates. At a molecular level, circadian rhythms are regulated by the so-called clock genes, which oscillate in a periodic manner. The protein products of clock genes are transcription factors that control their own and other genes’ transcription, collectively known as “clock-controlled genes.” Several brain regions other than the SCN express circadian rhythms of clock genes, including the amygdala, the olfactory bulb, the retina, and the cerebellum. Glia cells in these structures are expected to participate in rhythmicity. However, only certain types of glia cells may be called “glial clocks,” since they express PER-based circadian oscillators, which depend of the SCN for their synchronization. This contribution summarizes the current information about clock genes in glia cells, their plausible role as oscillators and their medical implications. PMID:27666286

  13. Melatonin Receptor Genes in Vertebrates

    Directory of Open Access Journals (Sweden)

    Hua Dong Yin

    2013-05-01

    Full Text Available Melatonin receptors are members of the G protein-coupled receptor (GPCR family. Three genes for melatonin receptors have been cloned. The MT1 (or Mel1a or MTNR1A and MT2 (or Mel1b or MTNR1B receptor subtypes are present in humans and other mammals, while an additional melatonin receptor subtype, Mel1c (or MTNR1C, has been identified in fish, amphibians and birds. Another melatonin related orphan receptor, GPR50, which does not bind melatonin, is found exclusively in mammals. The hormone melatonin is secreted primarily by the pineal gland, with highest levels occurring during the dark period of a circadian cycle. This hormone acts systemically in numerous organs. In the brain, it is involved in the regulation of various neural and endocrine processes, and it readjusts the circadian pacemaker, the suprachiasmatic nucleus. This article reviews recent studies of gene organization, expression, evolution and mutations of melatonin receptor genes of vertebrates. Gene polymorphisms reveal that numerous mutations are associated with diseases and disorders. The phylogenetic analysis of receptor genes indicates that GPR50 is an outgroup to all other melatonin receptor sequences. GPR50 may have separated from a melatonin receptor ancestor before the split between MTNR1C and the MTNR1A/B ancestor.

  14. An encyclopedia of mouse genes.

    Science.gov (United States)

    Marra, M; Hillier, L; Kucaba, T; Allen, M; Barstead, R; Beck, C; Blistain, A; Bonaldo, M; Bowers, Y; Bowles, L; Cardenas, M; Chamberlain, A; Chappell, J; Clifton, S; Favello, A; Geisel, S; Gibbons, M; Harvey, N; Hill, F; Jackson, Y; Kohn, S; Lennon, G; Mardis, E; Martin, J; Mila, L; McCann, R; Morales, R; Pape, D; Person, B; Prange, C; Ritter, E; Soares, M; Schurk, R; Shin, T; Steptoe, M; Swaller, T; Theising, B; Underwood, K; Wylie, T; Yount, T; Wilson, R; Waterston, R

    1999-02-01

    The laboratory mouse is the premier model system for studies of mammalian development due to the powerful classical genetic analysis possible (see also the Jackson Laboratory web site, http://www.jax.org/) and the ever-expanding collection of molecular tools. To enhance the utility of the mouse system, we initiated a program to generate a large database of expressed sequence tags (ESTs) that can provide rapid access to genes. Of particular significance was the possibility that cDNA libraries could be prepared from very early stages of development, a situation unrealized in human EST projects. We report here the development of a comprehensive database of ESTs for the mouse. The project, initiated in March 1996, has focused on 5' end sequences from directionally cloned, oligo-dT primed cDNA libraries. As of 23 October 1998, 352,040 sequences had been generated, annotated and deposited in dbEST, where they comprised 93% of the total ESTs available for mouse. EST data are versatile and have been applied to gene identification, comparative sequence analysis, comparative gene mapping and candidate disease gene identification, genome sequence annotation, microarray development and the development of gene-based map resources.

  15. Molecular Studies on Preproinsulin Gene

    Directory of Open Access Journals (Sweden)

    Sabir Sarah

    2016-01-01

    Full Text Available Insulin plays an important role in maintaining the blood glucose level of the body. The β-cells of pancreas produce insulin in the form of precursor that is preproinsulin. The gene of preproinsulin provides an interesting system for addressing question related to molecular evolution. Recombinant DNA technology has made it possible to isolate and sequence the chromosomal genes coding for unique protein products. Although preproinsulin of various organism has been isolated and cloned, but there is no report from buffalo (Bubalus bubalis that is our major livestock. The genomic DNA of buffalo was isolated using Laura-Lee-Boodram method. The part of preproinsulin gene (596bp and 520bp using BPPI-UPS and bpiful_F as forward and BC1-C as reverse primer was amplified. Cloning of amplified fragments of gene were performed in pCR 2.1 vector. Positive clones were screened on the basis of blue white selection. The band obtained on 596bp and 520bp after colony PCR confirmed the successful cloning of preproinsulin gene in pCR 2.1 vector.

  16. Comparative genomic analysis of eutherian kallikrein genes

    Directory of Open Access Journals (Sweden)

    Marko Premzl

    2017-03-01

    Full Text Available The present study made attempts to update and revise eutherian kallikrein genes implicated in major physiological and pathological processes and in medical molecular diagnostics. Using eutherian comparative genomic analysis protocol and free available genomic sequence assemblies, the tests of reliability of eutherian public genomic sequences annotated most comprehensive curated third party data gene data set of eutherian kallikrein genes including 121 complete coding sequences among 335 potential coding sequences. The present analysis first described 13 major gene clusters of eutherian kallikrein genes, and explained their differential gene expansion patterns. One updated classification and nomenclature of eutherian kallikrein genes was proposed, as new framework of future experiments.

  17. Endogenous mutagenesis in recombinant sulfolobus plasmids.

    Science.gov (United States)

    Sakofsky, Cynthia J; Grogan, Dennis W

    2013-06-01

    Low rates of replication errors in chromosomal genes of Sulfolobus spp. demonstrate that these extreme thermoacidophiles can maintain genome integrity in environments with high temperature and low pH. In contrast to this genetic stability, we observed unusually frequent mutation of the β-D-glycosidase gene (lacS) of a shuttle plasmid (pJlacS) propagated in Sulfolobus acidocaldarius. The resulting Lac(-) mutants also grew faster than the Lac(+) parent, thereby amplifying the impact of the frequent lacS mutations on the population. We developed a mutant accumulation assay and corrections for the effects of copy number and differential growth for this system; the resulting measurements and calculations yielded a corrected rate of 5.1 × 10(-4) mutational events at the lacS gene per plasmid replication. Analysis of independent lacS mutants revealed three types of mutations: (i) G · C-to-A · T transitions, (ii) slipped-strand events, and (iii) deletions. These mutations were frequent in plasmid-borne lacS expressed at a high level but not in single-copy lacS in the chromosome or at lower levels of expression in a plasmid. Substitution mutations arose at only two of 12 potential priming sites of the DNA primase of the pRN1 replicon, but nearly all these mutations created nonsense (chain termination) codons. The spontaneous mutation rate of plasmid-borne lacS was 175-fold higher under high-expression than under low-expression conditions. The results suggest that important DNA repair or replication fidelity functions are impaired or overwhelmed in pJlacS, with results analogous to those of the "transcription-associated mutagenesis" seen in bacteria and eukaryotes.

  18. Advancement and prospects of tumor gene therapy

    Institute of Scientific and Technical Information of China (English)

    Chao Zhang; Qing-Tao Wang; He Liu; Zhen-Zhu Zhang; Wen-Lin Huang

    2011-01-01

    Gene therapy is one of the most attractive fields in tumor therapy. In past decades, significant progress has been achieved. Various approaches, such as viral and non-viral vectors and physical methods, have been developed to make gene delivery safer and more efficient. Several therapeutic strategies have evolved, including gene-based (tumor suppressor genes, suicide genes, antiangiogenic genes, cytokine and oxidative stress-based genes) and RNA-based (antisense oligonucieotides and RNA interference) approaches. In addition, immune response-based strategies (dendritic cell- and T cell-based therapy) are also under investigation in tumor gene therapy. This review highlights the progress and recent developments in gene delivery systems, therapeutic strategies, and possible clinical directions for gene therapy.

  19. Novel genes in LDL metabolism

    DEFF Research Database (Denmark)

    Christoffersen, Mette; Tybjærg-Hansen, Anne

    2015-01-01

    -exome sequencing and 'exome chip' studies have additionally suggested several novel genes in LDL metabolism including insulin-induced gene 2, signal transducing adaptor family member 1, lysosomal acid lipase A, patatin-like phospholipase domain-containing protein 5 and transmembrane 6 superfamily member 2. Most......PURPOSE OF REVIEW: To summarize recent findings from genome-wide association studies (GWAS), whole-exome sequencing of patients with familial hypercholesterolemia and 'exome chip' studies pointing to novel genes in LDL metabolism. RECENT FINDINGS: The genetic loci for ATP-binding cassette...... transporters G5 and G8, Niemann-Pick C1-Like protein 1, sortilin-1, ABO blood-group glycosyltransferases, myosin regulatory light chain-interacting protein and cholesterol 7α-hydroxylase have all consistently been associated with LDL cholesterol levels and/or coronary artery disease in GWAS. Whole...

  20. Gene Therapy for Bone Engineering

    Directory of Open Access Journals (Sweden)

    Elizabeth eRosado Balmayor

    2015-02-01

    Full Text Available Bone has an intrinsic healing capacity that may be exceeded when the fracture gap is too big or unstable. In that moment, osteogenic measures needs to be taken by physicians. It is important to combine cells, scaffolds and growth factors and the correct mechanical conditions. Growth factors are clinically administered as recombinant proteins. They are, however, expensive and needed in high supraphysiological doses. Moreover, their half-life is short when administered to the fracture. Therefore, gene therapy may be an alternative. Cells can constantly produce the protein of interest in the correct folding, with the physiological glycosylation and in the needed amounts. Genes can be delivered in vivo or ex vivo by viral or non-viral methods. Adenovirus is mostly used. For the non-viral methods, hydrogels and recently sonoporation seem to be promising means. This review will give an overview of recent advancements in gene therapy approaches for bone regeneration strategies.

  1. The plant ADH gene family.

    Science.gov (United States)

    Strommer, Judith

    2011-04-01

    The structures, evolution and functions of alcohol dehydrogenase gene families and their products have been scrutinized for half a century. Our understanding of the enzyme structure and catalytic activity of plant alcohol dehydrogenase (ADH-P) is based on the vast amount of information available for its animal counterpart. The probable origins of the enzyme from a simple β-coil and eventual emergence from a glutathione-dependent formaldehyde dehydrogenase have been well described. There is compelling evidence that the small ADH gene families found in plants today are the survivors of multiple rounds of gene expansion and contraction. To the probable original function of their products in the terminal reaction of anaerobic fermentation have been added roles in yeast-like aerobic fermentation and the production of characteristic scents that act to attract animals that serve as pollinators or agents of seed dispersal and to protect against herbivores.

  2. Candidate genes in panic disorder

    DEFF Research Database (Denmark)

    Howe, A. S.; Buttenschön, Henriette N; Bani-Fatemi, A.

    2016-01-01

    The utilization of molecular genetics approaches in examination of panic disorder (PD) has implicated several variants as potential susceptibility factors for panicogenesis. However, the identification of robust PD susceptibility genes has been complicated by phenotypic diversity, underpowered...... association studies and ancestry-specific effects. In the present study, we performed a succinct review of case-control association studies published prior to April 2015. Meta-analyses were performed for candidate gene variants examined in at least three studies using the Cochrane Mantel-Haenszel fixed......-effect model. Secondary analyses were also performed to assess the influences of sex, agoraphobia co-morbidity and ancestry-specific effects on panicogenesis. Meta-analyses were performed on 23 variants in 20 PD candidate genes. Significant associations after correction for multiple testing were observed...

  3. Simplifying gene trees for easier comprehension

    OpenAIRE

    Mundry Marvin; Lott Paul-Ludwig; Sassenberg Christoph; Lorkowski Stefan; Fuellen Georg

    2006-01-01

    Abstract Background In the genomic age, gene trees may contain large amounts of data making them hard to read and understand. Therefore, an automated simplification is important. Results We present a simplification tool for gene trees called TreeSimplifier. Based on species tree information and HUGO gene names, it summarizes "monophyla". These monophyla correspond to subtrees of the gene tree where the evolution of a gene follows species phylogeny, and they are simplified to single leaves in ...

  4. Genes Contributing to the Development of Alcoholism

    OpenAIRE

    Edenberg, Howard J.

    2012-01-01

    Genetic factors (i.e., variations in specific genes) account for a substantial portion of the risk for alcoholism. However, identifying those genes and the specific variations involved is challenging. Researchers have used both case–control and family studies to identify genes related to alcoholism risk. In addition, different strategies such as candidate gene analyses and genome-wide association studies have been used. The strongest effects have been found for specific variants of genes that...

  5. Activities of Human Gene Nomenclature Committee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-16

    The objective of this project, shared between NIH and DOE, has been and remains to enable the medical genetics communities to use common names for genes that are discovered by different gene hunting groups, in different species. This effort provides consistent gene nomenclature and approved gene symbols to the community at large. This contributes to a uniform and consistent understanding of genomes, particularly the human as well as functional genomics based on comparisons between homologous genes in related species (human and mice).

  6. Electroporation-mediated gene delivery.

    Science.gov (United States)

    Young, Jennifer L; Dean, David A

    2015-01-01

    Electroporation has been used extensively to transfer DNA to bacteria, yeast, and mammalian cells in culture for the past 30 years. Over this time, numerous advances have been made, from using fields to facilitate cell fusion, delivery of chemotherapeutic drugs to cells and tissues, and most importantly, gene and drug delivery in living tissues from rodents to man. Electroporation uses electrical fields to transiently destabilize the membrane allowing the entry of normally impermeable macromolecules into the cytoplasm. Surprisingly, at the appropriate field strengths, the application of these fields to tissues results in little, if any, damage or trauma. Indeed, electroporation has even been used successfully in human trials for gene delivery for the treatment of tumors and for vaccine development. Electroporation can lead to between 100 and 1000-fold increases in gene delivery and expression and can also increase both the distribution of cells taking up and expressing the DNA as well as the absolute amount of gene product per cell (likely due to increased delivery of plasmids into each cell). Effective electroporation depends on electric field parameters, electrode design, the tissues and cells being targeted, and the plasmids that are being transferred themselves. Most importantly, there is no single combination of these variables that leads to greatest efficacy in every situation; optimization is required in every new setting. Electroporation-mediated in vivo gene delivery has proven highly effective in vaccine production, transgene expression, enzyme replacement, and control of a variety of cancers. Almost any tissue can be targeted with electroporation, including muscle, skin, heart, liver, lung, and vasculature. This chapter will provide an overview of the theory of electroporation for the delivery of DNA both in individual cells and in tissues and its application for in vivo gene delivery in a number of animal models.

  7. The frustrated gene: origins of eukaryotic gene expression

    OpenAIRE

    Madhani, Hiten D.

    2013-01-01

    Eukarytotic gene expression is frustrated by a series of steps that are generally not observed in prokaryotes and are therefore not essential for the basic chemistry of transcription and translation. Their evolution may have been driven by the need to defend against parasitic nucleic acids.

  8. Candidate Gene Identification of Flowering Time Genes in Cotton

    Directory of Open Access Journals (Sweden)

    Corrinne E. Grover

    2015-07-01

    Full Text Available Flowering time control is critically important to all sexually reproducing angiosperms in both natural ecological and agronomic settings. Accordingly, there is much interest in defining the genes involved in the complex flowering-time network and how these respond to natural and artificial selection, the latter often entailing transitions in day-length responses. Here we describe a candidate gene analysis in the cotton genus , which uses homologs from the well-described flowering network to bioinformatically and phylogenetically identify orthologs in the published genome sequence from Ulbr., one of the two model diploid progenitors of the commercially important allopolyploid cottons, L. and L. Presence and patterns of expression were evaluated from 13 aboveground tissues related to flowering for each of the candidate genes using allopolyploid as a model. Furthermore, we use a comparative context to determine copy number variability of each key gene family across 10 published angiosperm genomes. Data suggest a pattern of repeated loss of duplicates following ancient whole-genome doubling events in diverse lineages. The data presented here provide a foundation for understanding both the parallel evolution of day-length neutrality in domesticated cottons and the flowering-time network, in general, in this important crop plant.

  9. The KCNE genes in hypertrophic cardiomyopathy: a candidate gene study

    Directory of Open Access Journals (Sweden)

    Moolman-Smook Johanna C

    2011-10-01

    Full Text Available Abstract Background The gene family KCNE1-5, which encode modulating β-subunits of several repolarising K+-ion channels, has been associated with genetic cardiac diseases such as long QT syndrome, atrial fibrillation and Brugada syndrome. The minK peptide, encoded by KCNE1, is attached to the Z-disc of the sarcomere as well as the T-tubules of the sarcolemma. It has been suggested that minK forms part of an "electro-mechanical feed-back" which links cardiomyocyte stretching to changes in ion channel function. We examined whether mutations in KCNE genes were associated with hypertrophic cardiomyopathy (HCM, a genetic disease associated with an improper hypertrophic response. Results The coding regions of KCNE1, KCNE2, KCNE3, KCNE4, and KCNE5 were examined, by direct DNA sequencing, in a cohort of 93 unrelated HCM probands and 188 blood donor controls. Fifteen genetic variants, four previously unknown, were identified in the HCM probands. Eight variants were non-synonymous and one was located in the 3'UTR-region of KCNE4. No disease-causing mutations were found and no significant difference in the frequency of genetic variants was found between HCM probands and controls. Two variants of likely functional significance were found in controls only. Conclusions Mutations in KCNE genes are not a common cause of HCM and polymorphisms in these genes do not seem to be associated with a propensity to develop arrhythmia

  10. From gene to disease; hypophosphataemic rickets and the PHEX gene

    NARCIS (Netherlands)

    Jansen, M; van Dael, C.M.L.; Verrijn Stuart, A.A.; van der Hout, A.H.; Rump, P.

    2006-01-01

    X-linked hypophosphataemic rickets is associated with mutations in the PHEX gene on the short arm of the X chromosome, encoding a membrane-bound endoprotease which is predominantly expressed in osteoblasts. Defective PHEX function leaves phosphaturic peptides such as FGF23 uncleaved, enabling these

  11. Genomics of local adaptation with gene flow.

    Science.gov (United States)

    Tigano, Anna; Friesen, Vicki L

    2016-05-01

    Gene flow is a fundamental evolutionary force in adaptation that is especially important to understand as humans are rapidly changing both the natural environment and natural levels of gene flow. Theory proposes a multifaceted role for gene flow in adaptation, but it focuses mainly on the disruptive effect that gene flow has on adaptation when selection is not strong enough to prevent the loss of locally adapted alleles. The role of gene flow in adaptation is now better understood due to the recent development of both genomic models of adaptive evolution and genomic techniques, which both point to the importance of genetic architecture in the origin and maintenance of adaptation with gene flow. In this review, we discuss three main topics on the genomics of adaptation with gene flow. First, we investigate selection on migration and gene flow. Second, we discuss the three potential sources of adaptive variation in relation to the role of gene flow in the origin of adaptation. Third, we explain how local adaptation is maintained despite gene flow: we provide a synthesis of recent genomic models of adaptation, discuss the genomic mechanisms and review empirical studies on the genomics of adaptation with gene flow. Despite predictions on the disruptive effect of gene flow in adaptation, an increasing number of studies show that gene flow can promote adaptation, that local adaptations can be maintained despite high gene flow, and that genetic architecture plays a fundamental role in the origin and maintenance of local adaptation with gene flow.

  12. Gene expression throughout a vertebrate's embryogenesis

    Directory of Open Access Journals (Sweden)

    Hinton David E

    2011-02-01

    Full Text Available Abstract Background Describing the patterns of gene expression during embryonic development has broadened our understanding of the processes and patterns that define morphogenesis. Yet gene expression patterns have not been described throughout vertebrate embryogenesis. This study presents statistical analyses of gene expression during all 40 developmental stages in the teleost Fundulus heteroclitus using four biological replicates per stage. Results Patterns of gene expression for 7,000 genes appear to be important as they recapitulate developmental timing. Among the 45% of genes with significant expression differences between pairs of temporally adjacent stages, significant differences in gene expression vary from as few as five to more than 660. Five adjacent stages have disproportionately more significant changes in gene expression (> 200 genes relative to other stages: four to eight and eight to sixteen cell stages, onset of circulation, pre and post-hatch, and during complete yolk absorption. The fewest differences among adjacent stages occur during gastrulation. Yet, at stage 16, (pre-mid-gastrulation the largest number of genes has peak expression. This stage has an over representation of genes in oxidative respiration and protein expression (ribosomes, translational genes and proteases. Unexpectedly, among all ribosomal genes, both strong positive and negative correlations occur. Similar correlated patterns of expression occur among all significant genes. Conclusions These data provide statistical support for the temporal dynamics of developmental gene expression during all stages of vertebrate development.

  13. Gene therapy: Myth or reality?

    Science.gov (United States)

    Fischer, Alain

    2016-01-01

    Gene therapy has become a reality, although still a fragile one. Clinical benefit has been achieved over the last 17years in a limited number of medical conditions for which pathophysiological studies determined that they were favorable settings. They include inherited disorders of the immune system, leukodystrophies, possibly hemoglobinopathies, hemophilia B, and retinal dystrophies. Advances in the treatment of B-cell leukemias and lymphomas have also been achieved. Advances in vector development and possible usage of gene editing may lead to significant advances over the next years. Copyright © 2016. Published by Elsevier SAS.

  14. JavaGenes Molecular Evolution

    Science.gov (United States)

    Lohn, Jason; Smith, David; Frank, Jeremy; Globus, Al; Crawford, James

    2007-01-01

    JavaGenes is a general-purpose, evolutionary software system written in Java. It implements several versions of a genetic algorithm, simulated annealing, stochastic hill climbing, and other search techniques. This software has been used to evolve molecules, atomic force field parameters, digital circuits, Earth Observing Satellite schedules, and antennas. This version differs from version 0.7.28 in that it includes the molecule evolution code and other improvements. Except for the antenna code, JaveGenes is available for NASA Open Source distribution.

  15. Zipf's Law in Gene Expression

    CERN Document Server

    Furusawa, C; Furusawa, Chikara; Kaneko, Kunihiko

    2002-01-01

    Using data from gene expression databases on various organisms and tissues, including yeast, nematodes, human normal and cancer tissues, and embryonic stem cells, we found that the abundances of expressed genes exhibit a power-law distribution with an exponent close to -1, i.e., they obey Zipf's law. Furthermore, by simulations of a simple model with an intra-cellular reaction network, we found that Zipf's law of chemical abundance is a universal feature of cells where such a network optimizes the efficiency and faithfulness of self-reproduction. These findings provide novel insights into the nature of the organization of reaction dynamics in living cells.

  16. Zipf's Law in Gene Expression

    Science.gov (United States)

    Furusawa, Chikara; Kaneko, Kunihiko

    2003-02-01

    Using data from gene expression databases on various organisms and tissues, including yeast, nematodes, human normal and cancer tissues, and embryonic stem cells, we found that the abundances of expressed genes exhibit a power-law distribution with an exponent close to -1; i.e., they obey Zipf’s law. Furthermore, by simulations of a simple model with an intracellular reaction network, we found that Zipf’s law of chemical abundance is a universal feature of cells where such a network optimizes the efficiency and faithfulness of self-reproduction. These findings provide novel insights into the nature of the organization of reaction dynamics in living cells.

  17. FunGeneClusterS

    DEFF Research Database (Denmark)

    Vesth, Tammi Camilla; Brandl, Julian; Andersen, Mikael Rørdam

    2016-01-01

    and industrial biotechnology applications. We have previously published a method for accurate prediction of clusters from genome and transcriptome data, which could also suggest cross-chemistry, however, this method was limited both in the number of parameters which could be adjusted as well as in user......Secondary metabolites of fungi are receiving an increasing amount of interest due to their prolific bioactivities and the fact that fungal biosynthesis of secondary metabolites often occurs from co-regulated and co-located gene clusters. This makes the gene clusters attractive for synthetic biology...

  18. Correction of gene expression data

    DEFF Research Database (Denmark)

    Darbani Shirvanehdeh, Behrooz; Stewart, C. Neal, Jr.; Noeparvar, Shahin;

    2014-01-01

    This report investigates for the first time the potential inter-treatment bias source of cell number for gene expression studies. Cell-number bias can affect gene expression analysis when comparing samples with unequal total cellular RNA content or with different RNA extraction efficiencies...... an analytical approach to examine the suitability of correction methods by considering the inter-treatment bias as well as the inter-replicate variance, which allows use of the best correction method with minimum residual bias. Analyses of RNA sequencing and microarray data showed that the efficiencies...

  19. Clock genes, chronotypes and diseases

    Directory of Open Access Journals (Sweden)

    Bogdan I. Voinescu

    2009-08-01

    Full Text Available Many common diseases in humans (such as cancer, heart disease, diabetes mellitus orpsychiatric disorders, such as depression seem to be linked to disruptions of circadian cycles and toclock genes variation. It is unlikely that such diseases to be caused by a genetic variation within a singlegene. They must be influenced by complex interactions among multiple genes, as well as environmentaland lifestyle factors. Therefore, it is important to understand how the resulting perturbations in ourcircadian biology could affect our physiological processes and susceptibility to disease. Associationsbetween the polymorphisms of the main components of the circadian molecular clock, circadian type(also known as diurnal preference or chronotype and diseases are presented.

  20. Detecting Sequence Homology at the Gene Cluster Level with MultiGeneBlast

    NARCIS (Netherlands)

    Medema, Marnix H.; Takano, Eriko; Breitling, Rainer; Nowick, Katja

    2013-01-01

    The genes encoding many biomolecular systems and pathways are genomically organized in operons or gene clusters. With MultiGeneBlast, we provide a user-friendly and effective tool to perform homology searches with operons or gene clusters as basic units, instead of single genes. The contextualizatio

  1. Detecting Sequence Homology at the Gene Cluster Level with MultiGeneBlast

    NARCIS (Netherlands)

    Medema, Marnix H.; Takano, Eriko; Breitling, Rainer; Nowick, Katja

    The genes encoding many biomolecular systems and pathways are genomically organized in operons or gene clusters. With MultiGeneBlast, we provide a user-friendly and effective tool to perform homology searches with operons or gene clusters as basic units, instead of single genes. The

  2. A gene-based information gain method for detecting gene-gene interactions in case-control studies.

    Science.gov (United States)

    Li, Jin; Huang, Dongli; Guo, Maozu; Liu, Xiaoyan; Wang, Chunyu; Teng, Zhixia; Zhang, Ruijie; Jiang, Yongshuai; Lv, Hongchao; Wang, Limei

    2015-11-01

    Currently, most methods for detecting gene-gene interactions (GGIs) in genome-wide association studies are divided into SNP-based methods and gene-based methods. Generally, the gene-based methods can be more powerful than SNP-based methods. Some gene-based entropy methods can only capture the linear relationship between genes. We therefore proposed a nonparametric gene-based information gain method (GBIGM) that can capture both linear relationship and nonlinear correlation between genes. Through simulation with different odds ratio, sample size and prevalence rate, GBIGM was shown to be valid and more powerful than classic KCCU method and SNP-based entropy method. In the analysis of data from 17 genes on rheumatoid arthritis, GBIGM was more effective than the other two methods as it obtains fewer significant results, which was important for biological verification. Therefore, GBIGM is a suitable and powerful tool for detecting GGIs in case-control studies.

  3. Integrones: los coleccionistas de genes Integrons: gene collectors

    Directory of Open Access Journals (Sweden)

    J. A. Di Conza

    2010-02-01

    Full Text Available Los integrones son estructuras genéticas que han despertado gran interés, debido a que algunos de ellos vehiculizan genes de resistencia a los antimicrobianos. Están formados por un fragmento que codifica una integrasa (intI y, a continuación, una secuencia attI a la que se unen los genes en casetes que codifican diferentes mecanismos de resistencia. Dentro de intI, en su extremo 3´, hay una secuencia promotora Pc a partir de la cual se transcriben los casetes de resistencia integrados, ya que estos genes carecen de promotor. Sin embargo, estos casetes presentan una secuencia específica denominada attC, la cual es reconocida por la integrasa que se une, por recombinación, a la secuencia attI del integrón en la orientación adecuada para su expresión. Los integrones se han clasificado según la secuencia de su integrasa, pero en la actualidad se prefiere clasificarlos según su localización. Se habla, en general, de "integrones móviles" para referirse a aquellos asociados a secuencias de inserción, transposones y/o plásmidos conjugativos, los que en su mayoría median mecanismos de resistencia, y de "superintegrones", de localización cromosómica y con grandes arreglos de genes en casetes. Los integrones móviles de clase 1 son los más abundantes en aislamientos clínicos y suelen estar asociados a transposones del subgrupo Tn21, seguidos por los de clase 2, derivados principalmente de Tn7. Estos elementos no son móviles por sí mismos, pero su asociación con elementos que sí lo son facilita su transferencia horizontal, lo que explica su amplia difusión entre las bacterias. Esta revisión intenta recopilar la información disponible acerca de los integrones móviles descritos en Argentina hasta la fecha.Integrons gained great interest due to their participation in resistance gene recruitment and expression. Their basic structure includes a fragment that encodes an integrase (intI followed by a recognition sequence (attI into

  4. Dominance of IMP-4-Producing Enterobacter cloacae among Carbapenemase-Producing Enterobacteriaceae in Australia

    Science.gov (United States)

    Townell, Nicola; Nimmo, Graeme R.; George, Narelle M.; Robson, Jennifer; Vohra, Renu; Davis, Louise; Heney, Claire; Paterson, David L.

    2015-01-01

    The prevalence of carbapenemase-producing Enterobacteriaceae (CPE) has been increasing worldwide. blaIMP has been reported to be the predominant carbapenemase-encoding gene within Enterobacteriaceae in Australia. However, there are limited data currently available on CPE from Queensland, Australia. A total of 58 CPE isolates were isolated between July 2009 and March 2014 from Queensland hospitals. The clonality of isolates was determined by Diversilab repetitive sequence-based PCR. The isolates were investigated for the resistance mechanisms carbapenemase, extended-spectrum β-lactamase, and AmpC β-lactamase and for aminoglycoside resistance and plasmid-mediated quinolone resistance genes by PCR. The plasmid types associated with carbapenemase-encoding genes were characterized. The majority of the CPE were Enterobacter cloacae (n = 29). The majority of Queensland CPE isolates were IMP producers and comprised 11 species (n = 48). Nine NDM-producing Enterobacteriaceae were identified. One NDM-producing Klebsiella pneumoniae isolate coproduced OXA-48. One K. pneumoniae isolate was an OXA-181 producer. The incidence of IMP producers increased significantly in 2013. blaIMP-4 was found in all IMP-producing isolates. blaTEM, qnrB, and aacA4 were common among IMP-4 producers. The HI2 (67%) and L/M (21%) replicons were associated with blaIMP-4. All HI2 plasmids were of sequence type 1 (ST1). All but one of the NDM producers possessed blaCTX-M-15. The 16S rRNA methylase genes found among NDM producers were armA, rmtB, rmtC, and rmtF. The substantial increase in the prevalence of CPE in Queensland has been associated mainly with the emergence E. cloacae strains possessing HI2 plasmids carrying blaIMP-4 over the past 2 years. The importation of NDM producers and/or OXA-48-like producers in patients also contributed to the increased emergence of CPE. PMID:25918153

  5. Gene therapy on demand: site specific regulation of gene therapy.

    Science.gov (United States)

    Jazwa, Agnieszka; Florczyk, Urszula; Jozkowicz, Alicja; Dulak, Jozef

    2013-08-10

    Since 1990 when the first clinical gene therapy trial was conducted, much attention and considerable promise have been given to this form of treatment. Gene therapy has been used with success in patients suffering from severe combined immunodeficiency syndromes (X-SCID and ADA-deficiency), Leber's congenital amaurosis, hemophilia, β-thalassemia and adrenoleukodystrophy. Last year, the first therapeutic vector (Glybera) for treatment of lipoprotein lipase deficiency has been registered in the European Union. Nevertheless, there are still several numerous issues that need to be improved to make this technique more safe, effective and easily accessible for patients. Introduction of the therapeutic gene to the given cells should provide the level of expression which will restore the production of therapeutic protein to normal values or will provide therapeutic efficacy despite not fully physiological expression. However, in numerous diseases the expression of therapeutic genes has to be kept at certain level for some time, and then might be required to be switched off to be activated again when worsening of the symptoms may aggravate the risk of disease relapse. In such cases the promoters which are regulated by local conditions may be more required. In this article the special emphasis is to discuss the strategies of regulation of gene expression by endogenous stimuli. Particularly, the hypoxia- or miRNA-regulated vectors offer the possibilities of tight but, at the same time, condition-dependent and cell-specific expression. Such means have been already tested in certain pathophysiological conditions. This creates the chance for the translational approaches required for development of effective treatments of so far incurable diseases.

  6. Model-driven discovery of synergistic inhibitors against E. coli and S. enterica serovar Typhimurium targeting a novel synthetic lethal pair, aldA and prpC

    Directory of Open Access Journals (Sweden)

    Ramy Karam Aziz

    2015-09-01

    Full Text Available Mathematical models of biochemical networks form a cornerstone of bacterial systems biology. Inconsistencies between simulation output and experimental data point to gaps in knowledge about the fundamental biology of the organism. One such inconsistency centers on the gene aldA in Escherichia coli: it is essential in a computational model of E. coli metabolism, but experimentally it is not. Here we reconcile this disparity by providing evidence that aldA and prpC form a synthetic lethal pair, as the double knockout could only be created through complementation with a plasmid-borne copy of aldA. Moreover, virtual and biological screening against the two proteins led to a set of compounds that inhibited the growth of E. coli and Salmonella enterica serovar Typhimurium synergistically at 100 – 200 μM individual concentrations. These results highlight the power of metabolic models to drive basic biological discovery and their potential use to discover new combination antibiotics.

  7. Model-driven discovery of synergistic inhibitors against E. coli and S. enterica serovar Typhimurium targeting a novel synthetic lethal pair, aldA and prpC.

    Science.gov (United States)

    Aziz, Ramy K; Khaw, Valerie L; Monk, Jonathan M; Brunk, Elizabeth; Lewis, Robert; Loh, Suh I; Mishra, Arti; Nagle, Amrita A; Satyanarayana, Chitkala; Dhakshinamoorthy, Saravanakumar; Luche, Michele; Kitchen, Douglas B; Andrews, Kathleen A; Palsson, Bernhard Ø; Charusanti, Pep

    2015-01-01

    Mathematical models of biochemical networks form a cornerstone of bacterial systems biology. Inconsistencies between simulation output and experimental data point to gaps in knowledge about the fundamental biology of the organism. One such inconsistency centers on the gene aldA in Escherichia coli: it is essential in a computational model of E. coli metabolism, but experimentally it is not. Here, we reconcile this disparity by providing evidence that aldA and prpC form a synthetic lethal pair, as the double knockout could only be created through complementation with a plasmid-borne copy of aldA. Moreover, virtual and biological screening against the two proteins led to a set of compounds that inhibited the growth of E. coli and Salmonella enterica serovar Typhimurium synergistically at 100-200 μM individual concentrations. These results highlight the power of metabolic models to drive basic biological discovery and their potential use to discover new combination antibiotics.

  8. The emergence of bacterial "hopeful monsters".

    Science.gov (United States)

    Croucher, Nicholas J; Klugman, Keith P

    2014-07-29

    The global spread of antibiotic-resistant bacteria has largely been driven by the dissemination of successful lineages. A particularly important example is sequence type (ST) 258 of Klebsiella pneumoniae, a common cause of health care-associated infections. Representatives of this lineage carry a variable array of plasmid-borne resistance genes, typically including a carbapenemase effective against the full range of clinically important β-lactams. In their recent mBio article, Chen et al. [mBio 5(3):e01355-14] described how ST258 emerged through "hybridization" between two other strains, with a second recombination resulting in the diversification of a key antigen. This commentary describes the findings in the context of other examples where saltational evolution has resulted in the sudden emergence of important pathogenic bacteria. Copyright © 2014 Croucher and Klugman.

  9. State-of-the-art human gene therapy: part I. Gene delivery technologies.

    Science.gov (United States)

    Wang, Dan; Gao, Guangping

    2014-01-01

    Safe and effective gene delivery is a prerequisite for successful gene therapy. In the early age of human gene therapy, setbacks due to problematic gene delivery vehicles plagued the exciting therapeutic outcome. However, gene delivery technologies rapidly evolved ever since. With the advancement of gene delivery techniques, gene therapy clinical trials surged during the past decade. As the first gene therapy product (Glybera) has obtained regulatory approval and reached clinic, human gene therapy finally realized the promise that genes can be medicines. The diverse gene delivery techniques available today have laid the foundation for gene therapy applications in treating a wide range of human diseases. Some of the most urgent unmet medical needs, such as cancer and pandemic infectious diseases, have been tackled by gene therapy strategies with promising results. Furthermore, combining gene transfer with other breakthroughs in biomedical research and novel biotechnologies opened new avenues for gene therapy. Such innovative therapeutic strategies are unthinkable until now, and are expected to be revolutionary. In part I of this review, we introduced recent development of non-viral and viral gene delivery technology platforms. As cell-based gene therapy blossomed, we also summarized the diverse types of cells and vectors employed in ex vivo gene transfer. Finally, challenges in current gene delivery technologies for human use were discussed.

  10. Gene Expression in Trypanosomatid Parasites

    Directory of Open Access Journals (Sweden)

    Santiago Martínez-Calvillo

    2010-01-01

    Full Text Available The parasites Leishmania spp., Trypanosoma brucei, and Trypanosoma cruzi are the trypanosomatid protozoa that cause the deadly human diseases leishmaniasis, African sleeping sickness, and Chagas disease, respectively. These organisms possess unique mechanisms for gene expression such as constitutive polycistronic transcription of protein-coding genes and trans-splicing. Little is known about either the DNA sequences or the proteins that are involved in the initiation and termination of transcription in trypanosomatids. In silico analyses of the genome databases of these parasites led to the identification of a small number of proteins involved in gene expression. However, functional studies have revealed that trypanosomatids have more general transcription factors than originally estimated. Many posttranslational histone modifications, histone variants, and chromatin modifying enzymes have been identified in trypanosomatids, and recent genome-wide studies showed that epigenetic regulation might play a very important role in gene expression in this group of parasites. Here, we review and comment on the most recent findings related to transcription initiation and termination in trypanosomatid protozoa.

  11. Ethics of Gene Therapy Debated.

    Science.gov (United States)

    Borman, Stu

    1991-01-01

    Presented are the highlights of a press conference featuring biomedical ethicist LeRoy Walters of Georgetown University and attorney Andrew Kimbrell of the Foundation on Economic Trends. The opposing points of view of these two speakers serve to outline the pros and cons of the gene therapy issue. (CW)

  12. Patching genes to fight disease

    Energy Technology Data Exchange (ETDEWEB)

    Holzman, D.

    1990-09-03

    The National Institutes of Health has approved the first gene therapy experiments, one of which will try to cure cancer by bolstering the immune system. The applications of such therapy are limited, but the potential aid to people with genetic diseases is great.

  13. Codon Adaptation of Plastid Genes

    Science.gov (United States)

    Suzuki, Haruo; Morton, Brian R.

    2016-01-01

    Codon adaptation is codon usage bias that results from selective pressure to increase the translation efficiency of a gene. Codon adaptation has been studied across a wide range of genomes and some early analyses of plastids have shown evidence for codon adaptation in a limited set of highly expressed plastid genes. Here we study codon usage bias across all fully sequenced plastid genomes which includes representatives of the Rhodophyta, Alveolata, Cryptophyta, Euglenozoa, Glaucocystophyceae, Rhizaria, Stramenopiles and numerous lineages within the Viridiplantae, including Chlorophyta and Embryophyta. We show evidence that codon adaptation occurs in all genomes except for two, Theileria parva and Heicosporidium sp., both of which have highly reduced gene contents and no photosynthesis genes. We also show evidence that selection for codon adaptation increases the representation of the same set of codons, which we refer to as the adaptive codons, across this wide range of taxa, which is probably due to common features descended from the initial endosymbiont. We use various measures to estimate the relative strength of selection in the different lineages and show that it appears to be fairly strong in certain Stramenopiles and Chlorophyta lineages but relatively weak in many members of the Rhodophyta, Euglenozoa and Embryophyta. Given these results we propose that codon adaptation in plastids is widespread and displays the same general features as adaptation in eubacterial genomes. PMID:27196606

  14. Codon Adaptation of Plastid Genes.

    Directory of Open Access Journals (Sweden)

    Haruo Suzuki

    Full Text Available Codon adaptation is codon usage bias that results from selective pressure to increase the translation efficiency of a gene. Codon adaptation has been studied across a wide range of genomes and some early analyses of plastids have shown evidence for codon adaptation in a limited set of highly expressed plastid genes. Here we study codon usage bias across all fully sequenced plastid genomes which includes representatives of the Rhodophyta, Alveolata, Cryptophyta, Euglenozoa, Glaucocystophyceae, Rhizaria, Stramenopiles and numerous lineages within the Viridiplantae, including Chlorophyta and Embryophyta. We show evidence that codon adaptation occurs in all genomes except for two, Theileria parva and Heicosporidium sp., both of which have highly reduced gene contents and no photosynthesis genes. We also show evidence that selection for codon adaptation increases the representation of the same set of codons, which we refer to as the adaptive codons, across this wide range of taxa, which is probably due to common features descended from the initial endosymbiont. We use various measures to estimate the relative strength of selection in the different lineages and show that it appears to be fairly strong in certain Stramenopiles and Chlorophyta lineages but relatively weak in many members of the Rhodophyta, Euglenozoa and Embryophyta. Given these results we propose that codon adaptation in plastids is widespread and displays the same general features as adaptation in eubacterial genomes.

  15. Homeobox gene expression in Brachiopoda

    DEFF Research Database (Denmark)

    Altenburger, Andreas; Martinez, Pedro; Wanninger, Andreas

    2011-01-01

    The molecular control that underlies brachiopod ontogeny is largely unknown. In order to contribute to this issue we analyzed the expression pattern of two homeobox containing genes, Not and Cdx, during development of the rhynchonelliform (i.e., articulate) brachiopod Terebratalia transversa. Not...

  16. Positional cloning of deafness genes

    NARCIS (Netherlands)

    Kremer, H.; Cremers, F.P.M.

    2009-01-01

    The identification of the majority of the known causative genes involved in nonsyndromic sensorineural hearing loss (NSHL) started with linkage analysis as part of a positional cloning procedure. The human and mouse genome projects in combination with technical developments on genotyping, transcript

  17. [From gene to disease: cystinosis

    NARCIS (Netherlands)

    Levtchenko, E.N.; Wilmer, M.J.G.; Graaf-Hess, A.C. de; Heuvel, L.P.W.J. van den; Blom, H.J.; Monnens, L.A.H.

    2004-01-01

    Cystinosis is an autosomal recessive disorder caused by an impaired transport of cystine out of lysosomes. The most severe infantile form of cystinosis starts with Fanconi syndrome at the age of 3-6 months. Untreated patients develop renal failure before the age of 10. The cystinosis gene (CTNS) map

  18. Gene expression studies using microarrays

    NARCIS (Netherlands)

    Burgess, Janette

    2001-01-01

    1. The rapid progression of the collaborative sequencing programmes that are unravelling the complete genome sequences of many organisms are opening pathways for new approaches to gene analysis. As the sequence data become available, the bottleneck in biological research will shift to understanding

  19. Gene Testing for Hereditary Ataxia

    Science.gov (United States)

    ... should be reviewed. • Psychological assessment/Counseling – prior to testing, psychological evaluation is recommended to ensure the person being tested is as prepared as possible to receive the test results, and to ... Before gene testing is ordered, the coordinating physician may choose to ...

  20. Gene therapy and respiratory neuroplasticity.

    Science.gov (United States)

    Mantilla, Carlos B

    2017-01-01

    Breathing is a life-sustaining behavior that in mammals is accomplished by activation of dedicated muscles responsible for inspiratory and expiratory forces acting on the lung and chest wall. Motor control is exerted by specialized pools of motoneurons in the medulla and spinal cord innervated by projections from multiple centers primarily in the brainstem that act in concert to generate both the rhythm and pattern of ventilation. Perturbations that prevent the accomplishment of the full range of motor behaviors by respiratory muscles commonly result in significant morbidity and increased mortality. Recent developments in gene therapy and novel targeting strategies have contributed to deeper understanding of the organization of respiratory motor systems. Gene therapy has received widespread attention and substantial progress has been made in recent years with the advent of improved tools for vector design. Genes can be delivered via a variety of plasmids, synthetic or viral vectors and cell therapies. In recent years, adeno-associated viruses (AAV) have become one of the most commonly used vector systems, primarily because of the extensive characterization conducted to date and the versatility in targeting strategies. Recent studies highlight the power of using AAV to selectively and effectively transduce respiratory motoneurons and muscle fibers with promising therapeutic effects. This brief review summarizes current evidence for the use of gene therapy in respiratory disorders with a primary focus on interventions that address motor control and neuroplasticity, including regeneration, in the respiratory system.

  1. Homeobox genes and melatonin synthesis

    DEFF Research Database (Denmark)

    Rohde, Kristian; Møller, Morten; Rath, Martin Fredensborg

    2014-01-01

    ) transcription factor is believed to control pineal-specific Aanat expression. Based on recent advances in our understanding of Crx in the rodent pineal gland, we here suggest that homeobox genes play a role in adult pineal physiology both by ensuring pineal-specific Aanat expression and by facilitating cAMP...

  2. Gene therapy for heart failure.

    Science.gov (United States)

    Greenberg, Barry

    2017-04-01

    Novel strategies are needed to treat the growing population of heart failure patients. While new drug and device based therapies have improved outcomes over the past several decades, heart failure patients continue to experience amongst the lowest quality of life of any chronic disease, high likelihood of being hospitalized and marked reduction in survival. Better understanding of many of the basic mechanisms involved in the development of heart failure has helped identify abnormalities that could potentially be targeted by gene transfer. Despite success in experimental animal models, translating gene transfer strategies from the laboratory to the clinic remains at an early stage. This review provides an introduction to gene transfer as a therapy for treating heart failure, describes some of the many factors that need to be addressed in order for it to be successful and discusses some of the recent studies that have been carried out in heart failure patients. Insights from these studies highlight both the enormous promise of gene transfer and the obstacles that still need to be overcome for this treatment approach to be successful. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Amplification of kinetic oscillations in gene expression

    Science.gov (United States)

    Zhdanov, V. P.

    2008-10-01

    Because of the feedbacks between the DNA transcription and mRNA translation, the gene expression in cells may exhibit bistability and oscillations. The deterministic and stochastic calculations presented illustrate how the bistable kinetics of expression of one gene in a cell can be influenced by the kinetic oscillations in the expression of another gene. Due to stability of the states of the bistable kinetics of gene 1 and the relatively small difference between the maximum and minimum protein amounts during the oscillations of gene 2, the induced oscillations of gene 1 are found to typically be related either to the low-or high-reactive state of this gene. The quality of the induced oscillations may be appreciably better than that of the inducing oscillations. This means that gene 1 can serve as an amplifier of the kinetic oscillations of gene 2.

  4. Genome-wide Analysis of Gene Regulation

    DEFF Research Database (Denmark)

    Chen, Yun

    cells are capable of regulating their gene expression, so that each cell can only express a particular set of genes yielding limited numbers of proteins with specialized functions. Therefore a rigid control of differential gene expression is necessary for cellular diversity. On the other hand, aberrant...... gene regulation will disrupt the cell’s fundamental processes, which in turn can cause disease. Hence, understanding gene regulation is essential for deciphering the code of life. Along with the development of high throughput sequencing (HTS) technology and the subsequent large-scale data analysis......, genome-wide assays have increased our understanding of gene regulation significantly. This thesis describes the integration and analysis of HTS data across different important aspects of gene regulation. Gene expression can be regulated at different stages when the genetic information is passed from gene...

  5. Evidence based selection of housekeeping genes.

    Directory of Open Access Journals (Sweden)

    Hendrik J M de Jonge

    Full Text Available For accurate and reliable gene expression analysis, normalization of gene expression data against housekeeping genes (reference or internal control genes is required. It is known that commonly used housekeeping genes (e.g. ACTB, GAPDH, HPRT1, and B2M vary considerably under different experimental conditions and therefore their use for normalization is limited. We performed a meta-analysis of 13,629 human gene array samples in order to identify the most stable expressed genes. Here we show novel candidate housekeeping genes (e.g. RPS13, RPL27, RPS20 and OAZ1 with enhanced stability among a multitude of different cell types and varying experimental conditions. None of the commonly used housekeeping genes were present in the top 50 of the most stable expressed genes. In addition, using 2,543 diverse mouse gene array samples we were able to confirm the enhanced stability of the candidate novel housekeeping genes in another mammalian species. Therefore, the identified novel candidate housekeeping genes seem to be the most appropriate choice for normalizing gene expression data.

  6. Evolution of the chicken Toll-like receptor gene family: A story of gene gain and gene loss

    Directory of Open Access Journals (Sweden)

    Paton Ian R

    2008-02-01

    Full Text Available Abstract Background Toll-like receptors (TLRs perform a vital role in disease resistance through their recognition of pathogen associated molecular patterns (PAMPs. Recent advances in genomics allow comparison of TLR genes within and between many species. This study takes advantage of the recently sequenced chicken genome to determine the complete chicken TLR repertoire and place it in context of vertebrate genomic evolution. Results The chicken TLR repertoire consists of ten genes. Phylogenetic analyses show that six of these genes have orthologs in mammals and fish, while one is only shared by fish and three appear to be unique to birds. Furthermore the phylogeny shows that TLR1-like genes arose independently in fish, birds and mammals from an ancestral gene also shared by TLR6 and TLR10. All other TLRs were already present prior to the divergence of major vertebrate lineages 550 Mya (million years ago and have since been lost in certain lineages. Phylogenetic analysis shows the absence of TLRs 8 and 9 in chicken to be the result of gene loss. The notable exception to the tendency of gene loss in TLR evolution is found in chicken TLRs 1 and 2, each of which underwent gene duplication about 147 and 65 Mya, respectively. Conclusion Comparative phylogenetic analysis of vertebrate TLR genes provides insight into their patterns and processes of gene evolution, with examples of both gene gain and gene loss. In addition, these comparisons clarify the nomenclature of TLR genes in vertebrates.

  7. Gene transfer therapy in vascular diseases.

    Science.gov (United States)

    McKay, M J; Gaballa, M A

    2001-01-01

    Somatic gene therapy of vascular diseases is a promising new field in modern medicine. Recent advancements in gene transfer technology have greatly evolved our understanding of the pathophysiologic role of candidate disease genes. With this knowledge, the expression of selective gene products provides the means to test the therapeutic use of gene therapy in a multitude of medical conditions. In addition, with the completion of genome sequencing programs, gene transfer can be used also to study the biologic function of novel genes in vivo. Novel genes are delivered to targeted tissue via several different vehicles. These vectors include adenoviruses, retroviruses, plasmids, plasmid/liposomes, and oligonucleotides. However, each one of these vectors has inherent limitations. Further investigations into developing delivery systems that not only allow for efficient, targeted gene transfer, but also are stable and nonimmunogenic, will optimize the clinical application of gene therapy in vascular diseases. This review further discusses the available mode of gene delivery and examines six major areas in vascular gene therapy, namely prevention of restenosis, thrombosis, hypertension, atherosclerosis, peripheral vascular disease in congestive heart failure, and ischemia. Although we highlight some of the recent advances in the use of gene therapy in treating vascular disease discovered primarily during the past two years, many excellent studies published during that period are not included in this review due to space limitations. The following is a selective review of practical uses of gene transfer therapy in vascular diseases. This review primarily covers work performed in the last 2 years. For earlier work, the reader may refer to several excellent review articles. For instance, Belalcazer et al. (6) reviewed general aspects of somatic gene therapy and the different vehicles used for the delivery of therapeutic genes. Gene therapy in restenosis and stimulation of

  8. Empirical study of supervised gene screening

    Directory of Open Access Journals (Sweden)

    Ma Shuangge

    2006-12-01

    Full Text Available Abstract Background Microarray studies provide a way of linking variations of phenotypes with their genetic causations. Constructing predictive models using high dimensional microarray measurements usually consists of three steps: (1 unsupervised gene screening; (2 supervised gene screening; and (3 statistical model building. Supervised gene screening based on marginal gene ranking is commonly used to reduce the number of genes in the model building. Various simple statistics, such as t-statistic or signal to noise ratio, have been used to rank genes in the supervised screening. Despite of its extensive usage, statistical study of supervised gene screening remains scarce. Our study is partly motivated by the differences in gene discovery results caused by using different supervised gene screening methods. Results We investigate concordance and reproducibility of supervised gene screening based on eight commonly used marginal statistics. Concordance is assessed by the relative fractions of overlaps between top ranked genes screened using different marginal statistics. We propose a Bootstrap Reproducibility Index, which measures reproducibility of individual genes under the supervised screening. Empirical studies are based on four public microarray data. We consider the cases where the top 20%, 40% and 60% genes are screened. Conclusion From a gene discovery point of view, the effect of supervised gene screening based on different marginal statistics cannot be ignored. Empirical studies show that (1 genes passed different supervised screenings may be considerably different; (2 concordance may vary, depending on the underlying data structure and percentage of selected genes; (3 evaluated with the Bootstrap Reproducibility Index, genes passed supervised screenings are only moderately reproducible; and (4 concordance cannot be improved by supervised screening based on reproducibility.

  9. Gene functional similarity search tool (GFSST

    Directory of Open Access Journals (Sweden)

    Russo James J

    2006-03-01

    Full Text Available Abstract Background With the completion of the genome sequences of human, mouse, and other species and the advent of high throughput functional genomic research technologies such as biomicroarray chips, more and more genes and their products have been discovered and their functions have begun to be understood. Increasing amounts of data about genes, gene products and their functions have been stored in databases. To facilitate selection of candidate genes for gene-disease research, genetic association studies, biomarker and drug target selection, and animal models of human diseases, it is essential to have search engines that can retrieve genes by their functions from proteome databases. In recent years, the development of Gene Ontology (GO has established structured, controlled vocabularies describing gene functions, which makes it possible to develop novel tools to search genes by functional similarity. Results By using a statistical model to measure the functional similarity of genes based on the Gene Ontology directed acyclic graph, we developed a novel Gene Functional Similarity Search Tool (GFSST to identify genes with related functions from annotated proteome databases. This search engine lets users design their search targets by gene functions. Conclusion An implementation of GFSST which works on the UniProt (Universal Protein Resource for the human and mouse proteomes is available at GFSST Web Server. GFSST provides functions not only for similar gene retrieval but also for gene search by one or more GO terms. This represents a powerful new approach for selecting similar genes and gene products from proteome databases according to their functions.

  10. Vascular Gene Expression: A Hypothesis

    Directory of Open Access Journals (Sweden)

    Angélica Concepción eMartínez-Navarro

    2013-07-01

    Full Text Available The phloem is the conduit through which photoassimilates are distributed from autotrophic to heterotrophic tissues and is involved in the distribution of signaling molecules that coordinate plant growth and responses to the environment. Phloem function depends on the coordinate expression of a large array of genes. We have previously identified conserved motifs in upstream regions of the Arabidopsis genes, encoding the homologs of pumpkin phloem sap mRNAs, displaying expression in vascular tissues. This tissue-specific expression in Arabidopsis is predicted by the overrepresentation of GA/CT-rich motifs in gene promoters. In this work we have searched for common motifs in upstream regions of the homologous genes from plants considered to possess a primitive vascular tissue (a lycophyte, as well as from others that lack a true vascular tissue (a bryophyte, and finally from chlorophytes. Both lycophyte and bryophyte display motifs similar to those found in Arabidopsis with a significantly low E-value, while the chlorophytes showed either a different conserved motif or no conserved motif at all. These results suggest that these same genes are expressed coordinately in non- vascular plants; this coordinate expression may have been one of the prerequisites for the development of conducting tissues in plants. We have also analyzed the phylogeny of conserved proteins that may be involved in phloem function and development. The presence of CmPP16, APL, FT and YDA in chlorophytes suggests the recruitment of ancient regulatory networks for the development of the vascular tissue during evolution while OPS is a novel protein specific to vascular plants.

  11. STATE-OF-THE-ART HUMAN GENE THERAPY: PART II. GENE THERAPY STRATEGIES AND APPLICATIONS

    OpenAIRE

    2014-01-01

    In Part I of this Review, we introduced recent advances in gene delivery technologies and explained how they have powered some of the current human gene therapy applications. In Part II, we expand the discussion on gene therapy applications, focusing on some of the most exciting clinical uses. To help readers to grasp the essence and to better organize the diverse applications, we categorize them under four gene therapy strategies: (1) gene replacement therapy for monogenic diseases, (2) gene...

  12. Quantifying and resolving multiple vector transformants in S. cerevisiae plasmid libraries

    Directory of Open Access Journals (Sweden)

    Gray Elizabeth C

    2009-11-01

    Full Text Available Abstract Background In addition to providing the molecular machinery for transcription and translation, recombinant microbial expression hosts maintain the critical genotype-phenotype link that is essential for high throughput screening and recovery of proteins encoded by plasmid libraries. It is known that Escherichia coli cells can be simultaneously transformed with multiple unique plasmids and thusly complicate recombinant library screening experiments. As a result of their potential to yield misleading results, bacterial multiple vector transformants have been thoroughly characterized in previous model studies. In contrast to bacterial systems, there is little quantitative information available regarding multiple vector transformants in yeast. Saccharomyces cerevisiae is the most widely used eukaryotic platform for cell surface display, combinatorial protein engineering, and other recombinant library screens. In order to characterize the extent and nature of multiple vector transformants in this important host, plasmid-born gene libraries constructed by yeast homologous recombination were analyzed by DNA sequencing. Results It was found that up to 90% of clones in yeast homologous recombination libraries may be multiple vector transformants, that on average these clones bear four or more unique mutant genes, and that these multiple vector cells persist as a significant proportion of library populations for greater than 24 hours during liquid outgrowth. Both vector concentration and vector to insert ratio influenced the library proportion of multiple vector transformants, but their population frequency was independent of transformation efficiency. Interestingly, the average number of plasmids born by multiple vector transformants did not vary with their library population proportion. Conclusion These results highlight the potential for multiple vector transformants to dominate yeast libraries constructed by homologous recombination. The

  13. Gene doping: the hype and the harm.

    Science.gov (United States)

    McKanna, Trudy A; Toriello, Helga V

    2010-06-01

    "Gene doping" is the term used to describe the potential abuse of gene therapy as a performance-enhancing agent. Gene doping would apply the techniques used in gene therapy to provide altered expression of genes that would promote physical superiority. For example, insulin-like growth factor 1 (IGF-1) is a primary target for growth hormone; overexpression of IGF-1 can lead to increased muscle mass and power. Although gene doping is still largely theoretical, its implications for sports, health, ethics, and medical genetics are significant.

  14. Msx homeobox gene family and craniofacial development

    Institute of Scientific and Technical Information of China (English)

    SYLVIA ALAPPAT; ZUN YI ZHANG; YI PING CHEN

    2003-01-01

    Vertebrate Msx genes are unlinked,homeobox-containing genes that bear homology to the Drosophila muscle segment homeobox gene.These genes are expressed at multiple sites of tissue-tissue interactions during vertebrate embryonic development.Inductive interactions mediated by the Msx genes are essential for normal craniofacial,limb and ectodermal organ morphogenesis,and are also essential to survival in mice,as manifested by the phenotypic abnormalities shown in knockout mice and in humans.This review summarizes studies on the expression,regulation,and functional analysis of Msx genes that bear relevance to craniofacial development in humans and mice.

  15. Reshaping of global gene expression networks and sex‐biased gene expression by integration of a young gene

    National Research Council Canada - National Science Library

    Chen, Sidi; Ni, Xiaochun; Krinsky, Benjamin H; Zhang, Yong E; Vibranovski, Maria D; White, Kevin P; Long, Manyuan

    2012-01-01

    ...‐biased gene expression in Drosophila . This 4–6 million‐year‐old factor, named Zeus for its role in male fecundity, originated through retroposition of a highly conserved housekeeping gene, Caf40...

  16. GenePRIMP: A GENE PRediction IMprovement Pipeline for Prokaryotic genomes

    Energy Technology Data Exchange (ETDEWEB)

    Pati, Amrita; Ivanova, Natalia N.; Mikhailova, Natalia; Ovchinnikova, Galina; Hooper, Sean D.; Lykidis, Athanasios; Kyrpides, Nikos C.

    2010-04-01

    We present 'gene prediction improvement pipeline' (GenePRIMP; http://geneprimp.jgi-psf.org/), a computational process that performs evidence-based evaluation of gene models in prokaryotic genomes and reports anomalies including inconsistent start sites, missed genes and split genes. We found that manual curation of gene models using the anomaly reports generated by GenePRIMP improved their quality, and demonstrate the applicability of GenePRIMP in improving finishing quality and comparing different genome-sequencing and annotation technologies.

  17. Genes from scratch – the evolutionary fate of de novo genes

    Science.gov (United States)

    Schlötterer, Christian

    2015-01-01

    Although considered an extremely unlikely event, many genes emerge from previously noncoding genomic regions. This review covers the entire life cycle of such de novo genes. Two competing hypotheses about the process of de novo gene birth are discussed as well as the high death rate of de novo genes. Despite the high death rate, some de novo genes are retained and remain functional, even in distantly related species, through their integration into gene networks. Further studies combining gene expression with ribosome profiling in multiple populations across different species will be instrumental for an improved understanding of the evolutionary processes operating on de novo genes. PMID:25773713

  18. Detection of gene x gene interactions in genome-wide association studies of human population data

    National Research Council Canada - National Science Library

    Musani, Solomon K; Shriner, Daniel; Liu, Nianjun; Feng, Rui; Coffey, Christopher S; Yi, Nengjun; Tiwari, Hemant K; Allison, David B

    2007-01-01

    Empirical evidence supporting the commonality of gene x gene interactions, coupled with frequent failure to replicate results from previous association studies, has prompted statisticians to develop...

  19. Detection of gene expression pattern in the early stage after spinal cord injury by gene chip

    Institute of Scientific and Technical Information of China (English)

    刘成龙; 靳安民; 童斌辉

    2003-01-01

    Objective: To study the changes of the gene expression pattern of spinal cord tissues in the early stage after injury by DNA microarray (gene chip). Methods: The contusion model of rat spinal cord was established according to Allen's falling strike method and the gene expression patterns of normal and injured spinal cord tissues were studied by gene chip. Results: The expression of 45 genes was significantly changed in the early stage after spinal cord injury, in which 22 genes up-regulated and 23 genes down-regulated. Conclusions: The expression of some genes changes significantly in the early stage after spinal cord injury, which indicates the complexity of secondary spinal cord injury.

  20. The relationship among gene expression, the evolution of gene dosage, and the rate of protein evolution.

    Directory of Open Access Journals (Sweden)

    Jean-François Gout

    2010-05-01

    Full Text Available The understanding of selective constraints affecting genes is a major issue in biology. It is well established that gene expression level is a major determinant of the rate of protein evolution, but the reasons for this relationship remain highly debated. Here we demonstrate that gene expression is also a major determinant of the evolution of gene dosage: the rate of gene losses after whole genome duplications in the Paramecium lineage is negatively correlated to the level of gene expression, and this relationship is not a byproduct of other factors known to affect the fate of gene duplicates. This indicates that changes in gene dosage are generally more deleterious for highly expressed genes. This rule also holds for other taxa: in yeast, we find a clear relationship between gene expression level and the fitness impact of reduction in gene dosage. To explain these observations, we propose a model based on the fact that the optimal expression level of a gene corresponds to a trade-off between the benefit and cost of its expression. This COSTEX model predicts that selective pressure against mutations changing gene expression level or affecting the encoded protein should on average be stronger in highly expressed genes and hence that both the frequency of gene loss and the rate of protein evolution should correlate negatively with gene expression. Thus, the COSTEX model provides a simple and common explanation for the general relationship observed between the level of gene expression and the different facets of gene evolution.

  1. Genome-wide analysis of homeobox genes from Mesobuthus martensii reveals Hox gene duplication in scorpions.

    Science.gov (United States)

    Di, Zhiyong; Yu, Yao; Wu, Yingliang; Hao, Pei; He, Yawen; Zhao, Huabin; Li, Yixue; Zhao, Guoping; Li, Xuan; Li, Wenxin; Cao, Zhijian

    2015-06-01

    Homeobox genes belong to a large gene group, which encodes the famous DNA-binding homeodomain that plays a key role in development and cellular differentiation during embryogenesis in animals. Here, one hundred forty-nine homeobox genes were identified from the Asian scorpion, Mesobuthus martensii (Chelicerata: Arachnida: Scorpiones: Buthidae) based on our newly assembled genome sequence with approximately 248 × coverage. The identified homeobox genes were categorized into eight classes including 82 families: 67 ANTP class genes, 33 PRD genes, 11 LIM genes, five POU genes, six SINE genes, 14 TALE genes, five CUT genes, two ZF genes and six unclassified genes. Transcriptome data confirmed that more than half of the genes were expressed in adults. The homeobox gene diversity of the eight classes is similar to the previously analyzed Mandibulata arthropods. Interestingly, it is hypothesized that the scorpion M. martensii may have two Hox clusters. The first complete genome-wide analysis of homeobox genes in Chelicerata not only reveals the repertoire of scorpion, arachnid and chelicerate homeobox genes, but also shows some insights into the evolution of arthropod homeobox genes.

  2. Genes from scratch--the evolutionary fate of de novo genes.

    Science.gov (United States)

    Schlötterer, Christian

    2015-04-01

    Although considered an extremely unlikely event, many genes emerge from previously noncoding genomic regions. This review covers the entire life cycle of such de novo genes. Two competing hypotheses about the process of de novo gene birth are discussed as well as the high death rate of de novo genes. Despite the high death rate, some de novo genes are retained and remain functional, even in distantly related species, through their integration into gene networks. Further studies combining gene expression with ribosome profiling in multiple populations across different species will be instrumental for an improved understanding of the evolutionary processes operating on de novo genes.

  3. Newer Gene Editing Technologies toward HIV Gene Therapy

    OpenAIRE

    2013-01-01

    Despite the great success of highly active antiretroviral therapy (HAART) in ameliorating the course of HIV infection, alternative therapeutic approaches are being pursued because of practical problems associated with life-long therapy. The eradication of HIV in the so-called “Berlin patient” who received a bone marrow transplant from a CCR5-negative donor has rekindled interest in genome engineering strategies to achieve the same effect. Precise gene editing within the cells is now a realist...

  4. Database for exchangeable gene trap clones: pathway and gene ontology analysis of exchangeable gene trap clone mouse lines.

    Science.gov (United States)

    Araki, Masatake; Nakahara, Mai; Muta, Mayumi; Itou, Miharu; Yanai, Chika; Yamazoe, Fumika; Miyake, Mikiko; Morita, Ayaka; Araki, Miyuki; Okamoto, Yoshiyuki; Nakagata, Naomi; Yoshinobu, Kumiko; Yamamura, Ken-ichi; Araki, Kimi

    2014-02-01

    Gene trapping in embryonic stem (ES) cells is a proven method for large-scale random insertional mutagenesis in the mouse genome. We have established an exchangeable gene trap system, in which a reporter gene can be exchanged for any other DNA of interest through Cre/mutant lox-mediated recombination. We isolated trap clones, analyzed trapped genes, and constructed the database for Exchangeable Gene Trap Clones (EGTC) [http://egtc.jp]. The number of registered ES cell lines was 1162 on 31 August 2013. We also established 454 mouse lines from trap ES clones and deposited them in the mouse embryo bank at the Center for Animal Resources and Development, Kumamoto University, Japan. The EGTC database is the most extensive academic resource for gene-trap mouse lines. Because we used a promoter-trap strategy, all trapped genes were expressed in ES cells. To understand the general characteristics of the trapped genes in the EGTC library, we used Kyoto Encyclopedia of Genes and Genomes (KEGG) for pathway analysis and found that the EGTC ES clones covered a broad range of pathways. We also used Gene Ontology (GO) classification data provided by Mouse Genome Informatics (MGI) to compare the functional distribution of genes in each GO term between trapped genes in the EGTC mouse lines and total genes annotated in MGI. We found the functional distributions for the trapped genes in the EGTC mouse lines and for the RefSeq genes for the whole mouse genome were similar, indicating that the EGTC mouse lines had trapped a wide range of mouse genes. © 2014 The Authors Development, Growth & Differentiation © 2014 Japanese Society of Developmental Biologists.

  5. cis sequence effects on gene expression

    Directory of Open Access Journals (Sweden)

    Jacobs Kevin

    2007-08-01

    Full Text Available Abstract Background Sequence and transcriptional variability within and between individuals are typically studied independently. The joint analysis of sequence and gene expression variation (genetical genomics provides insight into the role of linked sequence variation in the regulation of gene expression. We investigated the role of sequence variation in cis on gene expression (cis sequence effects in a group of genes commonly studied in cancer research in lymphoblastoid cell lines. We estimated the proportion of genes exhibiting cis sequence effects and the proportion of gene expression variation explained by cis sequence effects using three different analytical approaches, and compared our results to the literature. Results We generated gene expression profiling data at N = 697 candidate genes from N = 30 lymphoblastoid cell lines for this study and used available candidate gene resequencing data at N = 552 candidate genes to identify N = 30 candidate genes with sufficient variance in both datasets for the investigation of cis sequence effects. We used two additive models and the haplotype phylogeny scanning approach of Templeton (Tree Scanning to evaluate association between individual SNPs, all SNPs at a gene, and diplotypes, with log-transformed gene expression. SNPs and diplotypes at eight candidate genes exhibited statistically significant (p cis sequence effects in our study, respectively. Conclusion Based on analysis of our results and the extant literature, one in four genes exhibits significant cis sequence effects, and for these genes, about 30% of gene expression variation is accounted for by cis sequence variation. Despite diverse experimental approaches, the presence or absence of significant cis sequence effects is largely supported by previously published studies.

  6. Gene set analysis using variance component tests

    Science.gov (United States)

    2013-01-01

    Background Gene set analyses have become increasingly important in genomic research, as many complex diseases are contributed jointly by alterations of numerous genes. Genes often coordinate together as a functional repertoire, e.g., a biological pathway/network and are highly correlated. However, most of the existing gene set analysis methods do not fully account for the correlation among the genes. Here we propose to tackle this important feature of a gene set to improve statistical power in gene set analyses. Results We propose to model the effects of an independent variable, e.g., exposure/biological status (yes/no), on multiple gene expression values in a gene set using a multivariate linear regression model, where the correlation among the genes is explicitly modeled using a working covariance matrix. We develop TEGS (Test for the Effect of a Gene Set), a variance component test for the gene set effects by assuming a common distribution for regression coefficients in multivariate linear regression models, and calculate the p-values using permutation and a scaled chi-square approximation. We show using simulations that type I error is protected under different choices of working covariance matrices and power is improved as the working covariance approaches the true covariance. The global test is a special case of TEGS when correlation among genes in a gene set is ignored. Using both simulation data and a published diabetes dataset, we show that our test outperforms the commonly used approaches, the global test and gene set enrichment analysis (GSEA). Conclusion We develop a gene set analyses method (TEGS) under the multivariate regression framework, which directly models the interdependence of the expression values in a gene set using a working covariance. TEGS outperforms two widely used methods, GSEA and global test in both simulation and a diabetes microarray data. PMID:23806107

  7. Gene Therapy and Gene Editing for the Corneal Dystrophies.

    Science.gov (United States)

    Williams, Keryn A; Irani, Yazad D

    2016-01-01

    Despite ever-increasing understanding of the genetic underpinnings of many corneal dystrophies, gene therapy designed to ameliorate disease has not yet been reported in any human patient. In this review, we explore the likely reasons for this apparent failure of translation. We identify the requirements for success: the genetic defect involved must have been identified and mapped, vision in the affected patient must be significantly impaired or likely to be impaired, no better or equivalently effective treatment must be available, the treatment must be capable of modulating corneal pathology, and delivery of the construct to the appropriate cell must be practicable. We consider which of the corneal dystrophies might be amenable to treatment by genetic manipulations, summarize existing therapeutic options for treatment, and explore gene editing using clustered regularly interspaced short palindromic repeat/Cas and other similar transformative technologies as the way of the future. We then summarize recent laboratory-based advances in gene delivery and the development of in vitro and in vivo models of the corneal dystrophies. Finally, we review recent experimental work that has increased our knowledge of the pathobiology of these conditions.

  8. Sequence and gene expression evolution of paralogous genes in willows.

    Science.gov (United States)

    Harikrishnan, Srilakshmy L; Pucholt, Pascal; Berlin, Sofia

    2015-12-22

    Whole genome duplications (WGD) have had strong impacts on species diversification by triggering evolutionary novelties, however, relatively little is known about the balance between gene loss and forces involved in the retention of duplicated genes originating from a WGD. We analyzed putative Salicoid duplicates in willows, originating from the Salicoid WGD, which took place more than 45 Mya. Contigs were constructed by de novo assembly of RNA-seq data derived from leaves and roots from two genotypes. Among the 48,508 contigs, 3,778 pairs were, based on fourfold synonymous third-codon transversion rates and syntenic positions, predicted to be Salicoid duplicates. Both copies were in most cases expressed in both tissues and 74% were significantly differentially expressed. Mean Ka/Ks was 0.23, suggesting that the Salicoid duplicates are evolving by purifying selection. Gene Ontology enrichment analyses showed that functions related to DNA- and nucleic acid binding were over-represented among the non-differentially expressed Salicoid duplicates, while functions related to biosynthesis and metabolism were over-represented among the differentially expressed Salicoid duplicates. We propose that the differentially expressed Salicoid duplicates are regulatory neo- and/or subfunctionalized, while the non-differentially expressed are dose sensitive, hence, functionally conserved. Multiple evolutionary processes, thus drive the retention of Salicoid duplicates in willows.

  9. Gene based therapies for kidney regeneration.

    Science.gov (United States)

    Janssen, Manoe J; Arcolino, Fanny O; Schoor, Perry; Kok, Robbert Jan; Mastrobattista, Enrico

    2016-11-05

    In this review we provide an overview of the expanding molecular toolbox that is available for gene based therapies and how these therapies can be used for a large variety of kidney diseases. Gene based therapies range from restoring gene function in genetic kidney diseases to steering complex molecular pathways in chronic kidney disorders, and can provide a treatment or cure for diseases that otherwise may not be targeted. This approach involves the delivery of recombinant DNA sequences harboring therapeutic genes to improve cell function and thereby promote kidney regeneration. Depending on the therapy, the recombinant DNA will express a gene that directly plays a role in the function of the cell (gene addition), that regulates the expression of an endogenous gene (gene regulation), or that even changes the DNA sequence of endogenous genes (gene editing). Some interventions involve permanent changes in the genome whereas others are only temporary and leave no trace. Efficient and safe delivery are important steps for all gene based therapies and also depend on the mode of action of the therapeutic gene. Here we provide examples on how the different methods can be used to treat various diseases, which technologies are now emerging (such as gene repair through CRISPR/Cas9) and what the opportunities, perspectives, potential and the limitations of these therapies are for the treatment of kidney diseases.

  10. Genomic evidence for adaptation by gene duplication.

    Science.gov (United States)

    Qian, Wenfeng; Zhang, Jianzhi

    2014-08-01

    Gene duplication is widely believed to facilitate adaptation, but unambiguous evidence for this hypothesis has been found in only a small number of cases. Although gene duplication may increase the fitness of the involved organisms by doubling gene dosage or neofunctionalization, it may also result in a simple division of ancestral functions into daughter genes, which need not promote adaptation. Hence, the general validity of the adaptation by gene duplication hypothesis remains uncertain. Indeed, a genome-scale experiment found similar fitness effects of deleting pairs of duplicate genes and deleting individual singleton genes from the yeast genome, leading to the conclusion that duplication rarely results in adaptation. Here we contend that the above comparison is unfair because of a known duplication bias among genes with different fitness contributions. To rectify this problem, we compare homologous genes from the budding yeast Saccharomyces cerevisiae and the fission yeast Schizosaccharomyces pombe. We discover that simultaneously deleting a duplicate gene pair in S. cerevisiae reduces fitness significantly more than deleting their singleton counterpart in S. pombe, revealing post-duplication adaptation. The duplicates-singleton difference in fitness effect is not attributable to a potential increase in gene dose after duplication, suggesting that the adaptation is owing to neofunctionalization, which we find to be explicable by acquisitions of binary protein-protein interactions rather than gene expression changes. These results provide genomic evidence for the role of gene duplication in organismal adaptation and are important for understanding the genetic mechanisms of evolutionary innovation.

  11. Thesaurus-based disambiguation of gene symbols

    Directory of Open Access Journals (Sweden)

    Wain Hester M

    2005-06-01

    Full Text Available Abstract Background Massive text mining of the biological literature holds great promise of relating disparate information and discovering new knowledge. However, disambiguation of gene symbols is a major bottleneck. Results We developed a simple thesaurus-based disambiguation algorithm that can operate with very little training data. The thesaurus comprises the information from five human genetic databases and MeSH. The extent of the homonym problem for human gene symbols is shown to be substantial (33% of the genes in our combined thesaurus had one or more ambiguous symbols, not only because one symbol can refer to multiple genes, but also because a gene symbol can have many non-gene meanings. A test set of 52,529 Medline abstracts, containing 690 ambiguous human gene symbols taken from OMIM, was automatically generated. Overall accuracy of the disambiguation algorithm was up to 92.7% on the test set. Conclusion The ambiguity of human gene symbols is substantial, not only because one symbol may denote multiple genes but particularly because many symbols have other, non-gene meanings. The proposed disambiguation approach resolves most ambiguities in our test set with high accuracy, including the important gene/not a gene decisions. The algorithm is fast and scalable, enabling gene-symbol disambiguation in massive text mining applications.

  12. Genes2GO: A web application for querying gene sets for specific GO terms.

    Science.gov (United States)

    Chawla, Konika; Kuiper, Martin

    2016-01-01

    Gene ontology annotations have become an essential resource for biological interpretations of experimental findings. The process of gathering basic annotation information in tables that link gene sets with specific gene ontology terms can be cumbersome, in particular if it requires above average computer skills or bioinformatics expertise. We have therefore developed Genes2GO, an intuitive R-based web application. Genes2GO uses the biomaRt package of Bioconductor in order to retrieve custom sets of gene ontology annotations for any list of genes from organisms covered by the Ensembl database. Genes2GO produces a binary matrix file, indicating for each gene the presence or absence of specific annotations for a gene. It should be noted that other GO tools do not offer this user-friendly access to annotations. Genes2GO is freely available and listed under http://www.semantic-systems-biology.org/tools/externaltools/.

  13. Progress in Chimeric Vector and Chimeric Gene Based Cardiovascular Gene Therapy

    Institute of Scientific and Technical Information of China (English)

    HU Chun-Song; YOON Young-sup; ISNER Jeffrey M.; LOSORDO Douglas W.

    2003-01-01

    Gene therapy for cardiovascular diseases has developed from preliminary animal experiments to clinical trials. However, vectors and target genes used currently in gene therapy are mainly focused on viral, nonviral vector and single target gene or monogene. Each vector system has a series of advantages and limitations. Chimeric vectors which combine the advantages of viral and nonviral vector,chimeric target genes which combine two or more target genes and novel gene delivery modes are being developed. In this article, we summarized the progress in chimeric vectors and chimeric genes based cardiovascular gene therapy, which including proliferative or occlusive vascular diseases such as atheroslerosis and restenosis, hypertonic vascular disease such as hypertension and cardiac diseases such as myocardium ischemia, dilated cardiomyopathy and heart failure, even heart transplantation. The development of chimeric vector, chimeric gene and their cardiovascular gene therapy is promising.

  14. Gene therapy for stroke: 2006 overview.

    Science.gov (United States)

    Chu, Yi; Miller, Jordan D; Heistad, Donald D

    2007-03-01

    Gene therapy is a promising approach for treatment of stroke and other cerebrovascular diseases, although it may take many years to realize. Gene therapy could occur prior to a stroke (eg, to stabilize atherosclerotic plaques) and/or following a stroke (eg, to prevent vasospasm after subarachnoid hemorrhage or reduce injury to neurons by ischemic insult). We have transferred the gene coding for vasoactive calcitonin gene-related peptide via cerebrospinal fluid, and demonstrated attenuation of vasospasm after SAH. Transfer of neuroprotective genes or small interfering RNA for neurotoxic genes has good potential for ischemic stroke. In this brief report, we review recent developments in experimental gene therapy for stroke. Fundamental advances, including development of safer, more specific gene transfer vectors, are discussed.

  15. NIH Researchers Identify OCD Risk Gene

    Science.gov (United States)

    ... News From NIH NIH Researchers Identify OCD Risk Gene Past Issues / Summer 2006 Table of Contents For ... and Alcoholism (NIAAA) have identified a previously unknown gene variant that doubles an individual's risk for obsessive- ...

  16. Mutation analysis of the preproghrelin gene

    DEFF Research Database (Denmark)

    Larsen, Lesli H; Gjesing, Anette P; Sørensen, Thorkild I A;

    2005-01-01

    To investigate the preproghrelin gene for variants and their association with obesity and type 2 diabetes.......To investigate the preproghrelin gene for variants and their association with obesity and type 2 diabetes....

  17. A fruit quality gene map of Prunus

    National Research Council Canada - National Science Library

    Ogundiwin, Ebenezer A; Peace, Cameron P; Gradziel, Thomas M; Parfitt, Dan E; Bliss, Fredrick A; Crisosto, Carlos H

    2009-01-01

    ... to marketing and consumption. Here we present an integrated fruit quality gene map of Prunus containing 133 genes putatively involved in the determination of fruit texture, pigmentation, flavor, and chilling injury resistance...

  18. Rogue Genes May Cause Some ALS Cases

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_166795.html Rogue Genes May Cause Some ALS Cases Most people with ... 21, 2017 WEDNESDAY, June 21, 2017 (HealthDay News) -- Gene mutations may cause up to 17 percent of ...

  19. Scientists Spot Genes Behind Crohn's, Ulcerative Colitis

    Science.gov (United States)

    ... medlineplus.gov/news/fullstory_166957.html Scientists Spot Genes Behind Crohn's, Ulcerative Colitis Large study finds key ... Researchers say they've come closer to pinpointing genes linked with inflammatory bowel diseases such as Crohn's ...

  20. Bioinformatics methods for identifying candidate disease genes

    NARCIS (Netherlands)

    Driel, M.A. van; Brunner, H.G.

    2006-01-01

    With the explosion in genomic and functional genomics information, methods for disease gene identification are rapidly evolving. Databases are now essential to the process of selecting candidate disease genes. Combining positional information with disease characteristics and functional information i

  1. What Is a Gene? (For Kids)

    Science.gov (United States)

    ... tested is replacing sick genes with healthy ones. Gene therapy trials — where the research is tested on people — and ... ON THIS TOPIC How to Deal With Hemophilia What's the Right Weight for Me? Do You ...

  2. Immunoglobulins and immunoglobulin genes of the horse.

    Science.gov (United States)

    Wagner, Bettina

    2006-01-01

    Antibodies of the horse were studied intensively by many notable immunologists throughout the past century until the early 1970's. After a large gap of interest in horse immunology, additional basic studies on horse immunoglobulin genes performed during the past 10 years have resulted in new insights into the equine humoral immune system. These include the characterization of the immunoglobulin lambda and kappa light chain genes, the immunoglobulin heavy chain constant (IGHC) gene regions, and initial studies regarding the heavy chain variable genes. Horses express predominately lambda light chains and seem to have a relatively restricted germline repertoire of both lambda and kappa chain variable genes. The IGHC region contains eleven constant heavy chain genes, seven of which are gamma heavy chain genes. It is suggested that all seven genes encoding IgG isotypes are expressed and have distinct functions in equine immune responses.

  3. New Cholesterol Fighting Meds Target Key Gene

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_165942.html New Cholesterol Fighting Meds Target Key Gene Two trials show ... New gene-based therapies appear to significantly decrease cholesterol levels in people, and could even cut down ...

  4. Gene therapy for obesity: progress and prospects.

    Science.gov (United States)

    Gao, Mingming; Liu, Dexi

    2014-06-01

    Advances in understanding the molecular basis of obesity and obesity-associated diseases have made gene therapy a vital approach in coping with this world-wide epidemic. Gene therapy for obesity aims to increase or decrease gene product in favor of lipolysis and energy expenditure, leading toward fat reduction and loss of body weight. It involves successful delivery and expression of therapeutic genes in appropriate cells. The ultimate goal of gene therapy is to restore and maintain energy homeostasis. Here we summarize progress made in recent years in identifying genes responsible for obesity and present examples where the gene therapy approach has been applied to treating or preventing obesity. Discussion on advantages and limitations of gene therapy strategies employed is provided. The intent of this review is to inspire further studies toward the development of new strategies for successful treatment of obesity and obesity-associated diseases.

  5. Biodegradable nanoparticles for gene therapy technology

    Energy Technology Data Exchange (ETDEWEB)

    Hosseinkhani, Hossein, E-mail: hosseinkhani@mail.ntust.edu.tw; He, Wen-Jie [National Taiwan University of Science and Technology (Taiwan Tech), Graduate Institute of Biomedical Engineering (China); Chiang, Chiao-Hsi [School of Pharmacy, National Defense Medical Center (China); Hong, Po-Da [National Taiwan University of Science and Technology (Taiwan Tech), Graduate Institute of Biomedical Engineering (China); Yu, Dah-Shyong [Nanomedicine Research Center, National Defense Medical Center (China); Domb, Abraham J. [The Hebrew University of Jerusalem, Institute of Drug Research, School of Pharmacy, Faculty of Medicine, Center for Nanoscience and Nanotechnology and The Alex Grass Center for Drug Design and Synthesis (Israel); Ou, Keng-Liang [College of Oral Medicine, Taipei Medical University, Research Center for Biomedical Devices and Prototyping Production (China)

    2013-07-15

    Rapid propagations in materials technology together with biology have initiated great hopes in the possibility of treating many diseases by gene therapy technology. Viral and non-viral gene carriers are currently applied for gene delivery. Non-viral technology is safe and effective for the delivery of genetic materials to cells and tissues. Non-viral systems are based on plasmid expression containing a gene encoding a therapeutic protein and synthetic biodegradable nanoparticles as a safe carrier of gene. Biodegradable nanoparticles have shown great interest in drug and gene delivery systems as they are easy to be synthesized and have no side effect in cells and tissues. This review provides a critical view of applications of biodegradable nanoparticles on gene therapy technology to enhance the localization of in vitro and in vivo and improve the function of administered genes.

  6. Researchers Pinpoint More Genes Linked to Vitiligo

    Science.gov (United States)

    ... 161452.html Researchers Pinpoint More Genes Linked to Vitiligo Genetic clues to this autoimmune disease could lead ... identified more genes linked to the autoimmune disease vitiligo, which causes patches of white skin and hair. ...

  7. BRCA1 and BRCA2 gene testing

    Science.gov (United States)

    ... of br east ca ncer. What is the BRCA Gene Mutation? BRCA1 and BRCA2 are genes that ... even negative results, with your genetic counselor. References BRCA and BRCA2: Cancer Risk and Genetic Testing. National ...

  8. In The Genes? Searching for Methuselah

    Science.gov (United States)

    ... Current Issue Past Issues Special Section In The Genes? Searching for Methuselah Past Issues / Winter 2007 Table ... 18 million effort to learn more about the genes, lifestyle or other factors that contribute to long, ...

  9. 'Uncombable' Hair? Maybe Genes Are to Blame

    Science.gov (United States)

    ... gov/news/fullstory_162727.html 'Uncombable' Hair? Maybe Genes Are to Blame Condition is rare, tends to ... combed normally. Now researchers say they've found genes linked to what's known as "uncombable hair syndrome." " ...

  10. Modulation of gene expression made easy

    DEFF Research Database (Denmark)

    Solem, Christian; Jensen, Peter Ruhdal

    2002-01-01

    A new approach for modulating gene expression, based on randomization of promoter (spacer) sequences, was developed. The method was applied to chromosomal genes in Lactococcus lactis and shown to generate libraries of clones with broad ranges of expression levels of target genes. In one example...... beta-glucuronidase, resulting in an operon structure in which both genes are transcribed from a common promoter. We show that there is a linear correlation between the expressions of the two genes, which facilitates screening for mutants with suitable enzyme activities. In a second example, we show......, overexpression was achieved by introducing an additional gene copy into a phage attachment site on the chromosome. This resulted in a series of strains with phosphofructokinase activities from 1.4 to 11 times the wild-type activity level. In this example, the pfk gene was cloned upstream of a gusA gene encoding...

  11. Phenotypic deconstruction of gene circuitry.

    Science.gov (United States)

    Lomnitz, Jason G; Savageau, Michael A

    2013-06-01

    It remains a challenge to obtain a global perspective on the behavioral repertoire of complex nonlinear gene circuits. In this paper, we describe a method for deconstructing complex systems into nonlinear sub-systems, based on mathematically defined phenotypes, which are then represented within a system design space that allows the repertoire of qualitatively distinct phenotypes of the complex system to be identified, enumerated, and analyzed. This method efficiently characterizes large regions of system design space and quickly generates alternative hypotheses for experimental testing. We describe the motivation and strategy in general terms, illustrate its use with a detailed example involving a two-gene circuit with a rich repertoire of dynamic behavior, and discuss experimental means of navigating the system design space.

  12. Mitochondriogenesis genes and extreme longevity.

    Science.gov (United States)

    Santiago, Catalina; Garatachea, Nuria; Yvert, Thomas; Rodríguez-Romo, Gabriel; Santos-Lozano, Alejandro; Fiuza-Luces, Carmen; Lucia, Alejandro

    2013-02-01

    Genes of the proliferator-activated receptor delta (PPARD)-peroxisome proliferator-activated receptor γ coactivator 1α (PPARGC1A, also termed PGC1-α)-nuclear respiratory factor (NRF)-mitochondrial transcription Factor A (TFAM) mitochondriogenesis pathway can influence health/disease phenotypes, yet their association with extreme longevity is not known. We studied the association of five common polymorphisms in genes of this pathway (rs2267668, rs8192678, rs6949152, rs12594956, rs1937) and extreme longevity using a case (107 centenarians)-control (284 young adults) design. We found no between-group differences in allele/genotype frequencies, except for CC genotype in rs1937 (p=0.003), with no representation in controls (0%), versus 2.8% in centenarians (2 men, 1 woman). In summary, the studied genetic variants of the PPARD-PPARGC1A-NRF-TFAM pathway were not associated with extreme longevity, yet a marginal association could exist for rs1937.

  13. Pumilio genes from the Platyhelminthes.

    Science.gov (United States)

    Koziol, Uriel; Marín, Monica; Castillo, Estela

    2008-01-01

    Pumilio proteins are proposed to have a conserved primordial function in the maintenance of proliferation in stem cells through post-transcriptional regulation. In this work, a search for pumilio homology domain (PUM-HD) sequences of pumilio genes from several Platyhelminthes species was performed, including representatives form Cestoda, Trematoda and Tricladida. Only one PUM-HD sequence was found in each triclad species; however, two PUM-HD homologues were found in all the parasitic species. These sequences formed two clearly separated clades: PlatyPum1, with sequences from all species, and PlatyPum2, composed exclusively of neodermatan sequences. Therefore, at least one duplication of the pumilio gene must have occurred before the divergence of cestodes and trematodes. Further duplications of PUM-HD were found in Fasciola hepatica, but these consist of retropseudogenes. This is the first comparative analysis of PUM-HD sequences in the Platyhelminthes and, more generally, in any lophotrochozoan phylum.

  14. Gene myths in public perceptions.

    Science.gov (United States)

    Svalastog, Anna Lydia

    2012-05-01

    In this article I examine myths in the gene science debate, and their use as a tool in analysis of popular perceptions and public opinion of genetic science and gene technology. In daily language myth means something untrue, though theories of myth present them as carriers of knowledge and truth. I understand myth as a narrative, a cultural construct that aims to describe the world, its origin, and its constituent elements. I compare scholars' usage of myths, considering their implications. I conclude that i) As an analytical tool the concept of myth is too loosely defined, or understood through theories which leave out context, social relations and interaction. This provides limited insight about myths and myth-making in present day society. ii) An updated understanding of myths, including location/context and interaction/process would enrich analysis.

  15. Gene coexpression network analysis as a source of functional annotation for rice genes.

    Directory of Open Access Journals (Sweden)

    Kevin L Childs

    Full Text Available With the existence of large publicly available plant gene expression data sets, many groups have undertaken data analyses to construct gene coexpression networks and functionally annotate genes. Often, a large compendium of unrelated or condition-independent expression data is used to construct gene networks. Condition-dependent expression experiments consisting of well-defined conditions/treatments have also been used to create coexpression networks to help examine particular biological processes. Gene networks derived from either condition-dependent or condition-independent data can be difficult to interpret if a large number of genes and connections are present. However, algorithms exist to identify modules of highly connected and biologically relevant genes within coexpression networks. In this study, we have used publicly available rice (Oryza sativa gene expression data to create gene coexpression networks using both condition-dependent and condition-independent data and have identified gene modules within these networks using the Weighted Gene Coexpression Network Analysis method. We compared the number of genes assigned to modules and the biological interpretability of gene coexpression modules to assess the utility of condition-dependent and condition-independent gene coexpression networks. For the purpose of providing functional annotation to rice genes, we found that gene modules identified by coexpression analysis of condition-dependent gene expression experiments to be more useful than gene modules identified by analysis of a condition-independent data set. We have incorporated our results into the MSU Rice Genome Annotation Project database as additional expression-based annotation for 13,537 genes, 2,980 of which lack a functional annotation description. These results provide two new types of functional annotation for our database. Genes in modules are now associated with groups of genes that constitute a collective functional

  16. Classification with binary gene expressions

    OpenAIRE

    Tuna, Salih; Niranjan, Mahesan

    2009-01-01

    Microarray gene expression measurements are reported, used and archived usually to high numerical precision. However, properties of mRNA molecules, such as their low stability and availability in small copy numbers, and the fact that measurements correspond to a population of cells, rather than a single cell, makes high precision meaningless. Recent work shows that reducing measurement precision leads to very little loss of information, right down to binary levels. In this paper we show how p...

  17. Gene Therapy for Fracture Repair

    Science.gov (United States)

    2007-05-01

    case, the external catheter hub is visible (D), though the internal tubing cannot be visualized by X-Ray. 11 MLV-based vector with BMP-2/4...catheter) injection. Top: A fluoroscope was used to visualize a radio- opaque contrast dye during a percutaneous injection from the lateral aspect...analysis was performed using ImaGene software (BioDiscovery, El Segundo, CA), that used an internal statistical analysis of the signal intensity of

  18. : Reelin gene variants in autism

    OpenAIRE

    Krebs, Marie-Odile; Betancur, Catalina; Leroy, Sophie; Bourdel, Marie-Chantal; Gillberg, Christopher; Leboyer, Marion

    2002-01-01

    Autism is a complex neurodevelopmental disorder with severe cognitive and communication disabilities, that has a strong genetic predisposition. Reelin, a protein involved in neuronal migration during development, is encoded by a gene located on 7q22, within the candidate region on 7q showing increased allele sharing in previous genome scans. A case/control and family-based association study recently reported a positive association between a trinucleotide repeat polymorphism (GGC) located in t...

  19. Gene Therapy for Childhood Neurofibromatosis

    Science.gov (United States)

    2014-05-01

    of cells heterozygous for the neurofibromin ( NF1 ) gene. Cells with two functional alleles of NF1 did not support tumor growth. The treatment...objective was therefore to increase the level of expression from the one active copy of NF1 to complement the haploinsufficiency in the cells of the tumor... NF1 ), artificial transcription factor, TALE DNA-binding protein, bacterial delivery vector 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF

  20. Genes for super-intelligence?

    Science.gov (United States)

    Sofaer, J A; Emery, A E

    1981-12-01

    The results of a postal questionnaire distributed to British members of Mensa failed to confirm an association of superior intelligence with torsion dystonia, retinoblastoma, or phenylketonuria, but were consistent with real associations between high IQ and infantile autism, gout, and myopia. Further confirmation of these findings in other populations might well indicate that genes producing these disorders have more or less direct effects on cerebral development and function.