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Genetics and Genomics

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Selected Works

2014

Articles 1 - 11 of 11

Full-Text Articles in Biology

Regulation Of Three Nitrogenase Gene Clusters In The Cyanobacterium Anabaena Variabilis Atcc 29413, Teresa Thiel, Brenda S. Pratte Dec 2014

Regulation Of Three Nitrogenase Gene Clusters In The Cyanobacterium Anabaena Variabilis Atcc 29413, Teresa Thiel, Brenda S. Pratte

Teresa Thiel

The filamentous cyanobacterium Anabaena variabilis ATCC 29413 fixes nitrogen under aerobic conditions in specialized cells called heterocysts that form in response to an environmental deficiency in combined nitrogen. Nitrogen fixation is mediated by the enzyme nitrogenase, which is very sensitive to oxygen. Heterocysts are microxic cells that allow nitrogenase to function in a filament comprised primarily of vegetative cells that produce oxygen by photosynthesis. A. variabilis is unique among well-characterized cyanobacteria in that it has three nitrogenase gene clusters that encode different nitrogenases, which function under different environmental conditions. The nif1 genes encode a Mo-nitrogenase that functions only in heterocysts, …

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Cloning And Expression Analysis Of Drosophila Extracellular Cu Zn Superoxide Dismutase, Michael J. Blackney, Rebecca Cox, David Shepherd, Joel D. Parker Dec 2014

Cloning And Expression Analysis Of Drosophila Extracellular Cu Zn Superoxide Dismutase, Michael J. Blackney, Rebecca Cox, David Shepherd, Joel D. Parker

Joel D Parker

In the present study, we cloned and sequenced the mRNAs of the Sod3 [extracellular Cu Zn SOD (superoxide dismutase)] gene in Drosophila and identified two mRNA products formed by alternative splicing. These products code for a long and short protein derived from the four transcripts found in global expression studies (Flybase numbers Dmel\CG9027, FBgn0033631). Both mRNA process variants contain an extracellular signalling sequence, a region of high homology to the Sod1 (cytoplasmic Cu Zn SOD) including a conserved AUG start, with the longer form also containing a hydrophobic tail. The two fully processed transcripts are homologous to Caenorhabditis elegans Sod3 …

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An Rnai-Based Suppressor Screen Identifies Interactors Of The Myt1 Ortholog Of Caenorhabditis Elegans, Anna K. Allen, Jessica E. Nesmith, Andy Golden Sep 2014

An Rnai-Based Suppressor Screen Identifies Interactors Of The Myt1 Ortholog Of Caenorhabditis Elegans, Anna K. Allen, Jessica E. Nesmith, Andy Golden

Anna Allen

Oocyte maturation in all species is controlled by a protein complex termed the maturation promoting factor (MPF). MPF is comprised of a cyclin-dependent kinase (CDK) and its partner cyclin, and is regulated by dueling regulatory phosphorylation events on the CDK. In Caenorhabditis elegans, the Wee1/Myt1 ortholog WEE-1.3 provides the inhibitory phosphorylations on CDK-1 that keep MPF inactive and halts meiosis. Prior work has shown that depletion of WEE-1.3 in C. elegans results in precocious oocyte maturation in vivo and a highly penetrant infertility phenotype. This study sought to further define the precocious maturation phenotype and to identify novel interactors with …

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Global Population-Specific Variation In Mirna Associated With Cancer Risk And Clinical Biomarkers, Renata A. Rawlings-Goss, Michael C. Campbell, Sarah A. Tishkoff Jul 2014

Global Population-Specific Variation In Mirna Associated With Cancer Risk And Clinical Biomarkers, Renata A. Rawlings-Goss, Michael C. Campbell, Sarah A. Tishkoff

Michael C. Campbell

Background: MiRNA expression profiling is being actively investigated as a clinical biomarker and diagnostic tool to detect multiple cancer types and stages as well as other complex diseases. Initial investigations, however, have not comprehensively taken into account genetic variability affecting miRNA expression and/or function in populations of different ethnic backgrounds. Therefore, more complete surveys of miRNA genetic variability are needed to assess global patterns of miRNA variation within and between diverse human populations and their effect on clinically relevant miRNA genes.

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Differential Expression Of Cyclin G2, Cyclin Dependent Kinase Inhibitor 2c And Peripheral Myelin Protein 22 Genes During Adipogenesis..Pdf, Jibin Zhang, Yeunsu Suh, Young Min Choi, Jinsoo Ahn, Michael E. Davis, Kichoon Lee May 2014

Differential Expression Of Cyclin G2, Cyclin Dependent Kinase Inhibitor 2c And Peripheral Myelin Protein 22 Genes During Adipogenesis..Pdf, Jibin Zhang, Yeunsu Suh, Young Min Choi, Jinsoo Ahn, Michael E. Davis, Kichoon Lee

Jibin Zhang

Increase of fat cells (FCs) in adipose tissue is attributed to proliferation of preadipocytes or immature adipocytes in the early stage, as well as adipogenic differentiation in the later stage of adipose development. Although both events are involved in the FC increase, they are contrary to each other, because the former requires cell cycle activity, whereas the latter requires cell cycle withdrawal. Therefore, appropriate regulation of cell cycle inhibition is critical to adipogenesis. In order to explore the important cell cycle inhibitors and study their expression in adipogenesis, we adopted a strategy combining the Gene Expression Omnibus (GEO) database available …

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Limited Evidence For Adaptive Evolution And Functional Effect Of Allelic Variation At Rs702424 In The Promoter Of The Tas2r16 Bitter Taste Receptor Gene In Africa, Michael C. Campbell Mar 2014

Limited Evidence For Adaptive Evolution And Functional Effect Of Allelic Variation At Rs702424 In The Promoter Of The Tas2r16 Bitter Taste Receptor Gene In Africa, Michael C. Campbell

Michael C. Campbell

Bitter taste perception, mediated by receptors encoded by the TAS2R loci, has important roles in human health and nutrition. Prior studies have demonstrated that nonsynonymous variation at site 516 in the coding exon of TAS2R16, a bitter taste receptor gene on chromosome 7, has been subject to positive selection and is strongly correlated with differences in sensitivity to salicin, a bitter anti-inflammatory compound, in human populations. However, a recent study suggested that the derived G-allele at rs702424 in the TAS2R16 promoter has also been the target of recent selection and may have an additional effect on the levels of salicin …

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Genetic Origins Of Lactase Persistence And The Spread Of Pastoralism In Africa, Michael C. Campbell Feb 2014

Genetic Origins Of Lactase Persistence And The Spread Of Pastoralism In Africa, Michael C. Campbell

Michael C. Campbell

In humans, the ability to digest lactose, the sugar in milk, declines after weaning because of decreasing levels of the enzyme lactase-phlorizin hydrolase, encoded by LCT. However, some individuals maintain high enzyme amounts and are able to digest lactose into adulthood (i.e., they have the lactase-persistence [LP] trait). It is thought that selection has played a major role in maintaining this genetically determined phenotypic trait in different human populations that practice pastoralism. To identify variants associated with the LP trait and to study its evolutionary history in Africa, we sequenced MCM6 introns 9 and 13 and ∼2 kb of the …

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A Comprehensive Microrna Expression Profile Of The Backfat Tissue From Castrated And Intact Full-Sib Pair Male Pigs.Pdf, Ying Bai, Jinming Huang, Gang Liu, Jibin Zhang, Jianying Wang, Chengkun Liu, Meiying Fang Jan 2014

A Comprehensive Microrna Expression Profile Of The Backfat Tissue From Castrated And Intact Full-Sib Pair Male Pigs.Pdf, Ying Bai, Jinming Huang, Gang Liu, Jibin Zhang, Jianying Wang, Chengkun Liu, Meiying Fang

Jibin Zhang

Background: It is widely known that castration has a significant effect on the accumulation of adipose tissue. microRNAs (miRNAs) are known to be involved in fat deposition and to be regulated by the androgen-induced androgen receptor (AR). However, there is little understanding of the relationship between miRNAs and fat deposition after castration. In this study, the high-throughput SOLiD sequencing approach was used to identify and characterize miRNA expression in backfat from intact and castrated full-sib male 23-week-old pigs. The patterns of adipogenesis and fat deposition were compared between castrated and intact male pigs.
Results: A total of 366 unique miRNA …

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Comparative Genomics Of Closely Related Salmonella Enterica Serovar Typhi Strains Reveals Genome Dynamics And The Acquisition Of Novel Pathogenic Elements, Kien-Pong Yap Jan 2014

Comparative Genomics Of Closely Related Salmonella Enterica Serovar Typhi Strains Reveals Genome Dynamics And The Acquisition Of Novel Pathogenic Elements, Kien-Pong Yap

Kien-Pong Yap

Background Typhoid fever is an infectious disease of global importance that is caused by Salmonella enterica subsp. enterica serovar Typhi (S. Typhi). This disease causes an estimated 200,000 deaths per year and remains a serious global health threat. S. Typhi is strictly a human pathogen, and some recovered individuals become long-term carriers who continue to shed the bacteria in their faeces, thus becoming main reservoirs of infection.

Results A comparative genomics analysis combined with a phylogenomic analysis revealed that the strains from the outbreak and carrier were closely related with microvariations and possibly derived from a common ancestor. Additionally, the …

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Frequency-Dependent Mate Selection In The Guppy (Poeciliidae: Poecilia Reticulata), Andre Porter, Jack Frankel Dec 2013

Frequency-Dependent Mate Selection In The Guppy (Poeciliidae: Poecilia Reticulata), Andre Porter, Jack Frankel

Jack Frankel

Heterogeneity within a population enhances its long-term survival. A fundamental method of maintaining population heterogeneity is the retention of rare or uncommon phenotypes by selective mating strategies. Employing two color morphs, red tuxedo and red, of the guppy (Poecilia reticulata, Poeciliidae), this study was designed to investigate whether P. reticulata females would preferentially seek out heterogeneous groupings of males exhibiting two color morphs. Adult female guppies were exposed simultaneously to two groups of males (n=10); one comprised of only the tuxedo color morph (n=5) and the other of both color morphs (n=5). For the latter group, the ratio of males …

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Complete Genome Sequence Of Anabaena Variabilis Atcc 29413, Teresa Thiel, Brenda S. Pratte, Jinshun Zhong, Lynne Goodwin, Alex Copeland, Susan Lucas, Cliff Han, Sam Pitluck, Miriam L. Land, Nikos C. Kyrpides, Tanja Woyke Dec 2013

Complete Genome Sequence Of Anabaena Variabilis Atcc 29413, Teresa Thiel, Brenda S. Pratte, Jinshun Zhong, Lynne Goodwin, Alex Copeland, Susan Lucas, Cliff Han, Sam Pitluck, Miriam L. Land, Nikos C. Kyrpides, Tanja Woyke

Teresa Thiel

Anabaena variabilis ATCC 29413 is a filamentous, heterocyst-forming cyanobacterium that has served as a model organism, with an extensive literature extending over 40 years. The strain has three distinct nitrogenases that function under different environmental conditions and is capable of photoautotrophic growth in the light and true heterotrophic growth in the dark using fructose as both carbon and energy source. While this strain was first isolated in 1964 in Mississippi and named Anabaena flos-aquae MSU A-37, it clusters phylogenetically with cyanobacteria of the genus Nostoc. The strain is a moderate thermophile, growing well at approximately 40° C. Here we provide …

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