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Full-Text Articles in Medicine and Health Sciences

Factors Associated With Blood Mercury Concentrations And Their Interactions With Three Glutathione S-Transferase Genes (Gstt1, Gstm1, And Gstp1): An Exposure Assessment Study Of Typically Developing Jamaican Children., Sheikh Farzana Zaman, Maureen Samms-Vaughan, Sepideh Saroukhani, Jan Bressler, Manouchehr Hessabi, Megan L Grove, Sydonnie Shakespeare Pellington, Katherine A Loveland, Mohammad H Rahbar Jan 2024

Factors Associated With Blood Mercury Concentrations And Their Interactions With Three Glutathione S-Transferase Genes (Gstt1, Gstm1, And Gstp1): An Exposure Assessment Study Of Typically Developing Jamaican Children., Sheikh Farzana Zaman, Maureen Samms-Vaughan, Sepideh Saroukhani, Jan Bressler, Manouchehr Hessabi, Megan L Grove, Sydonnie Shakespeare Pellington, Katherine A Loveland, Mohammad H Rahbar

Journal Articles

BACKGROUND: Jamaican soil is abundant in heavy metals including mercury (Hg). Due to availability and ease of access, fish is a traditional dietary component in Jamaica and a significant source of Hg exposure. Mercury is a xenobiotic and known neuro-toxicant that affects children's neurodevelopment. Human glutathione S-transferase (GST) genes, including GSTT1, GSTM1, and GSTP1, affect Hg conjugation and elimination mechanisms.

METHODS: In this exposure assessment study we used data from 375 typically developing (TD) 2-8-year-old Jamaican children to explore the association between environmental Hg exposure, GST genes, and their interaction effects on blood Hg concentrations (BHgCs). We used multivariable general …


Integrative Analysis Of Clinical And Epigenetic Biomarkers Of Mortality, Tianxiao Huan, Steve Nguyen, Elena Colicino, Carolina Ochoa-Rosales, W David Hill, Jennifer A Brody, Mette Soerensen, Yan Zhang, Antoine Baldassari, Mohamed Ahmed Elhadad, Tanaka Toshiko, Yinan Zheng, Arce Domingo-Relloso, Dong Heon Lee, Jiantao Ma, Chen Yao, Chunyu Liu, Shih-Jen Hwang, Roby Joehanes, Myriam Fornage, Jan Bressler, Joyce B J Van Meurs, Birgit Debrabant, Jonas Mengel-From, Jacob Hjelmborg, Kaare Christensen, Pantel Vokonas, Joel Schwartz, Sina A Gahrib, Nona Sotoodehnia, Colleen M Sitlani, Sonja Kunze, Christian Gieger, Annette Peters, Melanie Waldenberger, Ian J Deary, Luigi Ferrucci, Yishu Qu, Philip Greenland, Donald M Lloyd-Jones, Lifang Hou, Stefania Bandinelli, Trudy Voortman, Brenner Hermann, Andrea Baccarelli, Eric Whitsel, James S Pankow, Daniel Levy Jun 2022

Integrative Analysis Of Clinical And Epigenetic Biomarkers Of Mortality, Tianxiao Huan, Steve Nguyen, Elena Colicino, Carolina Ochoa-Rosales, W David Hill, Jennifer A Brody, Mette Soerensen, Yan Zhang, Antoine Baldassari, Mohamed Ahmed Elhadad, Tanaka Toshiko, Yinan Zheng, Arce Domingo-Relloso, Dong Heon Lee, Jiantao Ma, Chen Yao, Chunyu Liu, Shih-Jen Hwang, Roby Joehanes, Myriam Fornage, Jan Bressler, Joyce B J Van Meurs, Birgit Debrabant, Jonas Mengel-From, Jacob Hjelmborg, Kaare Christensen, Pantel Vokonas, Joel Schwartz, Sina A Gahrib, Nona Sotoodehnia, Colleen M Sitlani, Sonja Kunze, Christian Gieger, Annette Peters, Melanie Waldenberger, Ian J Deary, Luigi Ferrucci, Yishu Qu, Philip Greenland, Donald M Lloyd-Jones, Lifang Hou, Stefania Bandinelli, Trudy Voortman, Brenner Hermann, Andrea Baccarelli, Eric Whitsel, James S Pankow, Daniel Levy

Journal Articles

DNA methylation (DNAm) has been reported to be associated with many diseases and with mortality. We hypothesized that the integration of DNAm with clinical risk factors would improve mortality prediction. We performed an epigenome-wide association study of whole blood DNAm in relation to mortality in 15 cohorts (n = 15,013). During a mean follow-up of 10 years, there were 4314 deaths from all causes including 1235 cardiovascular disease (CVD) deaths and 868 cancer deaths. Ancestry-stratified meta-analysis of all-cause mortality identified 163 CpGs in European ancestry (EA) and 17 in African ancestry (AA) participants at p < 1 × 10


Elucidating Mechanisms Of Genetic Cross-Disease Associations At The Procr Vascular Disease Locus., David Stacey, Lingyan Chen, Paulina J Stanczyk, Joanna M M Howson, Amy M Mason, Stephen Burgess, Stephen Macdonald, Jonathan Langdown, Harriett Mckinney, Kate Downes, Neda Farahi, James E Peters, Saonli Basu, James S Pankow, Weihong Tang, Nathan Pankratz, Maria Sabater-Lleal, Paul S De Vries, Nicholas L Smith, Amy D Gelinas, Daniel J Schneider, Nebojsa Janjic, Nilesh J Samani, Shu Ye, Charlotte Summers, Edwin R Chilvers, John Danesh, Dirk S Paul Mar 2022

Elucidating Mechanisms Of Genetic Cross-Disease Associations At The Procr Vascular Disease Locus., David Stacey, Lingyan Chen, Paulina J Stanczyk, Joanna M M Howson, Amy M Mason, Stephen Burgess, Stephen Macdonald, Jonathan Langdown, Harriett Mckinney, Kate Downes, Neda Farahi, James E Peters, Saonli Basu, James S Pankow, Weihong Tang, Nathan Pankratz, Maria Sabater-Lleal, Paul S De Vries, Nicholas L Smith, Amy D Gelinas, Daniel J Schneider, Nebojsa Janjic, Nilesh J Samani, Shu Ye, Charlotte Summers, Edwin R Chilvers, John Danesh, Dirk S Paul

Journal Articles

Many individual genetic risk loci have been associated with multiple common human diseases. However, the molecular basis of this pleiotropy often remains unclear. We present an integrative approach to reveal the molecular mechanism underlying the PROCR locus, associated with lower coronary artery disease (CAD) risk but higher venous thromboembolism (VTE) risk. We identify PROCR-p.Ser219Gly as the likely causal variant at the locus and protein C as a causal factor. Using genetic analyses, human recall-by-genotype and in vitro experimentation, we demonstrate that PROCR-219Gly increases plasma levels of (activated) protein C through endothelial protein C receptor (EPCR) ectodomain shedding in endothelial cells, …


The Impact Of The Th17:Treg Axis On The Iga-Biome Across The Glycemic Spectrum, Heather T Essigmann, Kristi L Hoffman, Joseph F Petrosino, Goo Jun, David Aguilar, Craig L Hanis, Herbert L Dupont, Eric L Brown Jan 2021

The Impact Of The Th17:Treg Axis On The Iga-Biome Across The Glycemic Spectrum, Heather T Essigmann, Kristi L Hoffman, Joseph F Petrosino, Goo Jun, David Aguilar, Craig L Hanis, Herbert L Dupont, Eric L Brown

Journal Articles

Secretory IgA (SIgA) is released into mucosal surfaces where its function extends beyond that of host defense to include the shaping of resident microbial communities by mediating exclusion/inclusion of respective microbes and regulating bacterial gene expression. In this capacity, SIgA acts as the fulcrum on which host immunity and the health of the microbiota are balanced. We recently completed an analysis of the gut and salivary IgA-Biomes (16S rDNA sequencing of SIgA-coated/uncoated bacteria) in Mexican-American adults that identified IgA-Biome differences across the glycemic spectrum. As Th17:Treg ratio imbalances are associated with gut microbiome dysbiosis and chronic inflammatory conditions such as …


A Primer On A Comprehensive Genetic Approach To Vascular Anomalies, A. J. Borst, T. A. Nakano, F. Blei, D. M. Adams, J. Duis Jan 2020

A Primer On A Comprehensive Genetic Approach To Vascular Anomalies, A. J. Borst, T. A. Nakano, F. Blei, D. M. Adams, J. Duis

Journal Articles

No abstract provided.


De Novo Mutations In Congenital Heart Disease With Neurodevelopmental And Other Congenital Anomalies, J. Homsy, S. Zaidi, Y. Shen, J. S. Ware, K. E. Samocha, K. J. Karczewski, S. R. Depalma, D. Mckean, A. Romano-Adesman, W. K. Chung, +31 Additional Authors Jan 2015

De Novo Mutations In Congenital Heart Disease With Neurodevelopmental And Other Congenital Anomalies, J. Homsy, S. Zaidi, Y. Shen, J. S. Ware, K. E. Samocha, K. J. Karczewski, S. R. Depalma, D. Mckean, A. Romano-Adesman, W. K. Chung, +31 Additional Authors

Journal Articles

Congenital heart disease (CHD) patients have an increased prevalence of extracardiac congenital anomalies (CAs) and risk of neurodevelopmental disabilities (NDDs). Exome sequencing of 1213 CHD parent-offspring trios identified an excess of protein-damaging de novo mutations, especially in genes highly expressed in the developing heart and brain. These mutations accounted for 20% of patients with CHD, NDD, and CA but only 2% of patients with isolated CHD. Mutations altered genes involved in morphogenesis, chromatin modification, and transcriptional regulation, including multiple mutations in RBFOX2, a regulator of mRNA splicing. Genes mutated in other cohorts examined for NDD were enriched in CHD cases, …


Highly Variable Recessive Lethal Or Nearly Lethal Mutation Rates During Germ-Line Development Of Male Drosophila Melanogaster., Jian-Jun Gao, Xue-Rong Pan, Jing Hu, Li Ma, Jian-Min Wu, Ye-Lin Shao, Sara A Barton, Ronny C Woodruff, Ya-Ping Zhang, Yun-Xin Fu Sep 2011

Highly Variable Recessive Lethal Or Nearly Lethal Mutation Rates During Germ-Line Development Of Male Drosophila Melanogaster., Jian-Jun Gao, Xue-Rong Pan, Jing Hu, Li Ma, Jian-Min Wu, Ye-Lin Shao, Sara A Barton, Ronny C Woodruff, Ya-Ping Zhang, Yun-Xin Fu

Journal Articles

Each cell of higher organism adults is derived from a fertilized egg through a series of divisions, during which mutations can occur. Both the rate and timing of mutations can have profound impacts on both the individual and the population, because mutations that occur at early cell divisions will affect more tissues and are more likely to be transferred to the next generation. Using large-scale multigeneration screening experiments for recessive lethal or nearly lethal mutations of Drosophila melanogaster and recently developed statistical analysis, we show for male D. melanogaster that (i) mutation rates (for recessive lethal or nearly lethal) are …


Foxm1b Transcriptionally Regulates Vascular Endothelial Growth Factor Expression And Promotes The Angiogenesis And Growth Of Glioma Cells., Yujian Zhang, Nu Zhang, Bingbing Dai, Mingguang Liu, Raymond Sawaya, Keping Xie, Suyun Huang Nov 2008

Foxm1b Transcriptionally Regulates Vascular Endothelial Growth Factor Expression And Promotes The Angiogenesis And Growth Of Glioma Cells., Yujian Zhang, Nu Zhang, Bingbing Dai, Mingguang Liu, Raymond Sawaya, Keping Xie, Suyun Huang

Journal Articles

We previously found that FoxM1B is overexpressed in human glioblastomas and that forced FoxM1B expression in anaplastic astrocytoma cells leads to the formation of highly angiogenic glioblastoma in nude mice. However, the molecular mechanisms by which FoxM1B enhances glioma angiogenesis are currently unknown. In this study, we found that vascular endothelial growth factor (VEGF) is a direct transcriptional target of FoxM1B. FoxM1B overexpression increased VEGF expression, whereas blockade of FoxM1 expression suppressed VEGF expression in glioma cells. Transfection of FoxM1 into glioma cells directly activated the VEGF promoter, and inhibition of FoxM1 expression by FoxM1 siRNA suppressed VEGF promoter activation. …


The Ubiquitin-Proteasome System Is Necessary For Long-Term Synaptic Depression In Aplysia, Diasinou Fioravante, Rong-Yu Liu, John H. Byrne Oct 2008

The Ubiquitin-Proteasome System Is Necessary For Long-Term Synaptic Depression In Aplysia, Diasinou Fioravante, Rong-Yu Liu, John H. Byrne

Journal Articles

The neuropeptide Phe-Met-Arg-Phe-NH(2) (FMRFa) can induce transcription-dependent long-term synaptic depression (LTD) in Aplysia sensorimotor synapses. We investigated the role of the ubiquitin-proteasome system and the regulation of one of its components, ubiquitin C-terminal hydrolase (ap-uch), in LTD. LTD was sensitive to presynaptic inhibition of the proteasome and was associated with upregulation of ap-uch mRNA and protein. This upregulation appeared to be mediated by CREB2, which is generally regarded as a transcription repressor. Binding of CREB2 to the promoter region of ap-uch was accompanied by histone hyperacetylation, suggesting that CREB2 cannot only inhibit but also promote gene expression. CREB2 was phosphorylated …


Genetic Variation In Genes For The Xenobiotic-Metabolizing Enzymes Cyp1a1, Ephx1, Gstm1, Gstt1, And Gstp1 And Susceptibility To Colorectal Cancer In Lynch Syndrome., Mala Pande, Christopher I Amos, Daniel R Osterwisch, Jinyun Chen, Patrick M Lynch, Russell Broaddus, Marsha L Frazier Sep 2008

Genetic Variation In Genes For The Xenobiotic-Metabolizing Enzymes Cyp1a1, Ephx1, Gstm1, Gstt1, And Gstp1 And Susceptibility To Colorectal Cancer In Lynch Syndrome., Mala Pande, Christopher I Amos, Daniel R Osterwisch, Jinyun Chen, Patrick M Lynch, Russell Broaddus, Marsha L Frazier

Journal Articles

Individuals with Lynch syndrome are predisposed to cancer due to an inherited DNA mismatch repair gene mutation. However, there is significant variability observed in disease expression likely due to the influence of other environmental, lifestyle, or genetic factors. Polymorphisms in genes encoding xenobiotic-metabolizing enzymes may modify cancer risk by influencing the metabolism and clearance of potential carcinogens from the body. In this retrospective analysis, we examined key candidate gene polymorphisms in CYP1A1, EPHX1, GSTT1, GSTM1, and GSTP1 as modifiers of age at onset of colorectal cancer among 257 individuals with Lynch syndrome. We found that subjects heterozygous for CYP1A1 I462V …


An Sp1/Sp3 Binding Polymorphism Confers Methylation Protection., Yanis A. Boumber, Yutaka Kondo, Xuqi Chen, Lanlan Shen, Yi Guo, Carmen Tellez, Marcos R H Estécio, Saira Ahmed, Jean-Pierre J. Issa Aug 2008

An Sp1/Sp3 Binding Polymorphism Confers Methylation Protection., Yanis A. Boumber, Yutaka Kondo, Xuqi Chen, Lanlan Shen, Yi Guo, Carmen Tellez, Marcos R H Estécio, Saira Ahmed, Jean-Pierre J. Issa

Journal Articles

Hundreds of genes show aberrant DNA hypermethylation in cancer, yet little is known about the causes of this hypermethylation. We identified RIL as a frequent methylation target in cancer. In search for factors that influence RIL hypermethylation, we found a 12-bp polymorphic sequence around its transcription start site that creates a long allele. Pyrosequencing of homozygous tumors revealed a 2.1-fold higher methylation for the short alleles (P<0.001). Bisulfite sequencing of cancers heterozygous for RIL showed that the short alleles are 3.1-fold more methylated than the long (P<0.001). The comparison of expression levels between unmethylated long and short EBV-transformed cell lines showed no difference in expression in vivo. Electrophorectic mobility shift assay showed that the inserted region of the long allele binds Sp1 and Sp3 transcription factors, a binding that is absent in the short allele. Transient transfection of RIL allele-specific transgenes showed no effects of the additional Sp1 site on transcription early on. However, stable transfection of methylation-seeded constructs showed gradually decreasing transcription levels from the short allele with eventual spreading of de novo methylation. In contrast, the long allele showed stable levels of expression over time as measured by luciferase and approximately 2-3-fold lower levels of methylation by bisulfite sequencing (P<0.001), suggesting that the polymorphic Sp1 site protects against time-dependent silencing. Our finding demonstrates that, in some genes, hypermethylation in cancer is dictated by protein-DNA interactions at the promoters and provides a novel mechanism by which genetic polymorphisms can influence an epigenetic state.


Rtr1 Is The Saccharomyces Cerevisiae Homolog Of A Novel Family Of Rna Polymerase Ii-Binding Proteins, Patrick A Gibney, Thomas Fries, Susanne M Bailer, Kevin A Morano Jun 2008

Rtr1 Is The Saccharomyces Cerevisiae Homolog Of A Novel Family Of Rna Polymerase Ii-Binding Proteins, Patrick A Gibney, Thomas Fries, Susanne M Bailer, Kevin A Morano

Journal Articles

Cells must rapidly sense and respond to a wide variety of potentially cytotoxic external stressors to survive in a constantly changing environment. In a search for novel genes required for stress tolerance in Saccharomyces cerevisiae, we identified the uncharacterized open reading frame YER139C as a gene required for growth at 37 degrees C in the presence of the heat shock mimetic formamide. YER139C encodes the closest yeast homolog of the human RPAP2 protein, recently identified as a novel RNA polymerase II (RNAPII)-associated factor. Multiple lines of evidence support a role for this gene family in transcription, prompting us to rename …


Activation Of Heat Shock And Antioxidant Responses By The Natural Product Celastrol: Transcriptional Signatures Of A Thiol-Targeted Molecule, Amy Trott, James D West, Lada Klaić, Sandy D Westerheide, Richard B Silverman, Richard I Morimoto, Kevin A Morano Mar 2008

Activation Of Heat Shock And Antioxidant Responses By The Natural Product Celastrol: Transcriptional Signatures Of A Thiol-Targeted Molecule, Amy Trott, James D West, Lada Klaić, Sandy D Westerheide, Richard B Silverman, Richard I Morimoto, Kevin A Morano

Journal Articles

Stress response pathways allow cells to sense and respond to environmental changes and adverse pathophysiological states. Pharmacological modulation of cellular stress pathways has implications in the treatment of human diseases, including neurodegenerative disorders, cardiovascular disease, and cancer. The quinone methide triterpene celastrol, derived from a traditional Chinese medicinal herb, has numerous pharmacological properties, and it is a potent activator of the mammalian heat shock transcription factor HSF1. However, its mode of action and spectrum of cellular targets are poorly understood. We show here that celastrol activates Hsf1 in Saccharomyces cerevisiae at a similar effective concentration seen in mammalian cells. Transcriptional …


Sp1 Up-Regulates Camp-Response-Element-Binding Protein Expression During Retinoic Acid-Induced Mucous Differentiation Of Normal Human Bronchial Epithelial Cells., Jeong Soo Hong, Seung-Wook Kim, Ja Seok Koo Feb 2008

Sp1 Up-Regulates Camp-Response-Element-Binding Protein Expression During Retinoic Acid-Induced Mucous Differentiation Of Normal Human Bronchial Epithelial Cells., Jeong Soo Hong, Seung-Wook Kim, Ja Seok Koo

Journal Articles

CREB [CRE (cAMP-response element)-binding protein] is an important transcription factor that is differentially regulated in cells of various types. We recently reported that RA (retinoic acid) rapidly activates CREB without using RARs (RA receptors) or RXRs (retinoid X receptors) in NHTBE cells (normal human tracheobronchial epithelial cells). However, little is known about the role of RA in the physiological regulation of CREB expression in the early mucous differentiation of NHTBE cells. In the present study, we report that RA up-regulates CREB gene expression and that, using 5'-serial deletion promoter analysis and mutagenesis analyses, two Sp1 (specificity protein 1)-binding sites located …


Eomesodermin, A Target Gene Of Pou4f2, Is Required For Retinal Ganglion Cell And Optic Nerve Development In The Mouse., Chai-An Mao, Takae Kiyama, Ping Pan, Yasuhide Furuta, Anna-Katerina Hadjantonakis, William H Klein Jan 2008

Eomesodermin, A Target Gene Of Pou4f2, Is Required For Retinal Ganglion Cell And Optic Nerve Development In The Mouse., Chai-An Mao, Takae Kiyama, Ping Pan, Yasuhide Furuta, Anna-Katerina Hadjantonakis, William H Klein

Journal Articles

The mechanisms regulating retinal ganglion cell (RGC) development are crucial for retinogenesis and for the establishment of normal vision. However, these mechanisms are only vaguely understood. RGCs are the first neuronal lineage to segregate from pluripotent progenitors in the developing retina. As output neurons, RGCs display developmental features very distinct from those of the other retinal cell types. To better understand RGC development, we have previously constructed a gene regulatory network featuring a hierarchical cascade of transcription factors that ultimately controls the expression of downstream effector genes. This has revealed the existence of a Pou domain transcription factor, Pou4f2, that …


Messenger Rna Half-Life Measurements In Mammalian Cells, Chyi-Ying A Chen, Nader Ezzeddine, Ann-Bin Shyu Jan 2008

Messenger Rna Half-Life Measurements In Mammalian Cells, Chyi-Ying A Chen, Nader Ezzeddine, Ann-Bin Shyu

Journal Articles

The recognition of the importance of mRNA turnover in regulating eukaryotic gene expression has mandated the development of reliable, rigorous, and "user-friendly" methods to accurately measure changes in mRNA stability in mammalian cells. Frequently, mRNA stability is studied indirectly by analyzing the steady-state level of mRNA in the cytoplasm; in this case, changes in mRNA abundance are assumed to reflect only mRNA degradation, an assumption that is not always correct. Although direct measurements of mRNA decay rate can be performed with kinetic labeling techniques and transcriptional inhibitors, these techniques often introduce significant changes in cell physiology. Furthermore, many critical mechanistic …


Versatile Applications Of Transcriptional Pulsing To Study Mrna Turnover In Mammalian Cells, Chyi-Ying A Chen, Yukiko Yamashita, Tsung-Cheng Chang, Akio Yamashita, Wenmiao Zhu, Zhenping Zhong, Ann-Bin Shyu Oct 2007

Versatile Applications Of Transcriptional Pulsing To Study Mrna Turnover In Mammalian Cells, Chyi-Ying A Chen, Yukiko Yamashita, Tsung-Cheng Chang, Akio Yamashita, Wenmiao Zhu, Zhenping Zhong, Ann-Bin Shyu

Journal Articles

Development of transcriptional pulsing approaches using the c-fos and Tet-off promoter systems greatly facilitated studies of mRNA turnover in mammalian cells. However, optimal protocols for these approaches vary for different cell types and/or physiological conditions, limiting their widespread application. In this study, we have further optimized transcriptional pulsing systems for different cell lines and developed new protocols to facilitate investigation of various aspects of mRNA turnover. We apply the Tet-off transcriptional pulsing strategy to investigate ARE-mediated mRNA decay in human erythroleukemic K562 cells arrested at various phases of the cell cycle by pharmacological inhibitors. This application facilitates studies of the …


Computational Identification And Functional Validation Of Regulatory Motifs In Cartilage-Expressed Genes, Sherri R Davies, Li-Wei Chang, Debabrata Patra, Xiaoyun Xing, Karen Posey, Jacqueline Hecht, Gary D Stormo, Linda J Sandell Oct 2007

Computational Identification And Functional Validation Of Regulatory Motifs In Cartilage-Expressed Genes, Sherri R Davies, Li-Wei Chang, Debabrata Patra, Xiaoyun Xing, Karen Posey, Jacqueline Hecht, Gary D Stormo, Linda J Sandell

Journal Articles

Chondrocyte gene regulation is important for the generation and maintenance of cartilage tissues. Several regulatory factors have been identified that play a role in chondrogenesis, including the positive transacting factors of the SOX family such as SOX9, SOX5, and SOX6, as well as negative transacting factors such as C/EBP and delta EF1. However, a complete understanding of the intricate regulatory network that governs the tissue-specific expression of cartilage genes is not yet available. We have taken a computational approach to identify cis-regulatory, transcription factor (TF) binding motifs in a set of cartilage characteristic genes to better define the transcriptional regulatory …


Agrobacterium Para/Mind-Like Virc1 Spatially Coordinates Early Conjugative Dna Transfer Reactions, Krishnamohan Atmakuri, Eric Cascales, Oliver T Burton, Lois M Banta, Peter J Christie May 2007

Agrobacterium Para/Mind-Like Virc1 Spatially Coordinates Early Conjugative Dna Transfer Reactions, Krishnamohan Atmakuri, Eric Cascales, Oliver T Burton, Lois M Banta, Peter J Christie

Journal Articles

Agrobacterium tumefaciens translocates T-DNA through a polar VirB/D4 type IV secretion (T4S) system. VirC1, a factor required for efficient T-DNA transfer, bears a deviant Walker A and other sequence motifs characteristic of ParA and MinD ATPases. Here, we show that VirC1 promotes conjugative T-DNA transfer by stimulating generation of multiple copies per cell of the T-DNA substrate (T-complex) through pairwise interactions with the processing factors VirD2 relaxase, VirC2, and VirD1. VirC1 also associates with the polar membrane and recruits T-complexes to cell poles, the site of VirB/D4 T4S machine assembly. VirC1 Walker A mutations abrogate T-complex generation and polar recruitment, …


Dynamics Of A Minimal Model Of Interlocked Positive And Negative Feedback Loops Of Transcriptional Regulation By Camp-Response Element Binding Proteins, Hao Song, Paul Smolen, Evyatar Av-Ron, Douglas A Baxter, John H Byrne May 2007

Dynamics Of A Minimal Model Of Interlocked Positive And Negative Feedback Loops Of Transcriptional Regulation By Camp-Response Element Binding Proteins, Hao Song, Paul Smolen, Evyatar Av-Ron, Douglas A Baxter, John H Byrne

Journal Articles

cAMP-response element binding (CREB) proteins are involved in transcriptional regulation in a number of cellular processes (e.g., neural plasticity and circadian rhythms). The CREB family contains activators and repressors that may interact through positive and negative feedback loops. These loops can be generated by auto- and cross-regulation of expression of CREB proteins, via CRE elements in or near their genes. Experiments suggest that such feedback loops may operate in several systems (e.g., Aplysia and rat). To understand the functional implications of such feedback loops, which are interlocked via cross-regulation of transcription, a minimal model with a positive and negative loop …


Single-Stranded Dna-Binding Proteins Regulate The Abundance Of Lim Domain And Lim Domain-Binding Proteins., Zhixiong Xu, Xianzhang Meng, Ying Cai, Hong Liang, Lalitha Nagarajan, Stephen J Brandt Apr 2007

Single-Stranded Dna-Binding Proteins Regulate The Abundance Of Lim Domain And Lim Domain-Binding Proteins., Zhixiong Xu, Xianzhang Meng, Ying Cai, Hong Liang, Lalitha Nagarajan, Stephen J Brandt

Journal Articles

The LIM domain-binding protein Ldb1 is an essential cofactor of LIM-homeodomain (LIM-HD) and LIM-only (LMO) proteins in development. The stoichiometry of Ldb1, LIM-HD, and LMO proteins is tightly controlled in the cell and is likely a critical determinant of their biological actions. Single-stranded DNA-binding proteins (SSBPs) were recently shown to interact with Ldb1 and are also important in developmental programs. We establish here that two mammalian SSBPs, SSBP2 and SSBP3, contribute to an erythroid DNA-binding complex that contains the transcription factors Tal1 and GATA-1, the LIM domain protein Lmo2, and Ldb1 and binds a bipartite E-box-GATA DNA sequence motif. In …


A Pure Population Of Lung Alveolar Epithelial Type Ii Cells Derived From Human Embryonic Stem Cells, Dachun Wang, David L Haviland, Alan R Burns, Eva Zsigmond, Rick A Wetsel Mar 2007

A Pure Population Of Lung Alveolar Epithelial Type Ii Cells Derived From Human Embryonic Stem Cells, Dachun Wang, David L Haviland, Alan R Burns, Eva Zsigmond, Rick A Wetsel

Journal Articles

Alveolar epithelial type II (ATII) cells are small, cuboidal cells that constitute approximately 60% of the pulmonary alveolar epithelium. These cells are crucial for repair of the injured alveolus by differentiating into alveolar epithelial type I cells. ATII cells derived from human ES (hES) cells are a promising source of cells that could be used therapeutically to treat distal lung diseases. We have developed a reliable transfection and culture procedure, which facilitates, via genetic selection, the differentiation of hES cells into an essentially pure (>99%) population of ATII cells (hES-ATII). Purity, as well as biological features and morphological characteristics …


Aldosterone-Induced Sgk1 Relieves Dot1a-Af9-Mediated Transcriptional Repression Of Epithelial Na+ Channel Alpha, Wenzheng Zhang, Xuefeng Xia, Mary Rose Reisenauer, Timo Rieg, Florian Lang, Dietmar Kuhl, Volker Vallon, Bruce C Kone Mar 2007

Aldosterone-Induced Sgk1 Relieves Dot1a-Af9-Mediated Transcriptional Repression Of Epithelial Na+ Channel Alpha, Wenzheng Zhang, Xuefeng Xia, Mary Rose Reisenauer, Timo Rieg, Florian Lang, Dietmar Kuhl, Volker Vallon, Bruce C Kone

Journal Articles

Aldosterone plays a major role in the regulation of salt balance and the pathophysiology of cardiovascular and renal diseases. Many aldosterone-regulated genes--including that encoding the epithelial Na+ channel (ENaC), a key arbiter of Na+ transport in the kidney and other epithelia--have been identified, but the mechanisms by which the hormone modifies chromatin structure and thus transcription remain unknown. We previously described the basal repression of ENaCalpha by a complex containing the histone H3 Lys79 methyltransferase disruptor of telomeric silencing alternative splice variant a (Dot1a) and the putative transcription factor ALL1-fused gene from chromosome 9 (Af9) as well as the release …


Genome Sequence Of Fusobacterium Nucleatum Subspecies Polymorphum - A Genetically Tractable Fusobacterium, Sandor E Karpathy, Xiang Qin, Jason Gioia, Huaiyang Jiang, Yamei Liu, Joseph F Petrosino, Shailaja Yerrapragada, George E Fox, Susan Kinder Haake, George M Weinstock, Sarah K Highlander Jan 2007

Genome Sequence Of Fusobacterium Nucleatum Subspecies Polymorphum - A Genetically Tractable Fusobacterium, Sandor E Karpathy, Xiang Qin, Jason Gioia, Huaiyang Jiang, Yamei Liu, Joseph F Petrosino, Shailaja Yerrapragada, George E Fox, Susan Kinder Haake, George M Weinstock, Sarah K Highlander

Journal Articles

Fusobacterium nucleatum is a prominent member of the oral microbiota and is a common cause of human infection. F. nucleatum includes five subspecies: polymorphum, nucleatum, vincentii, fusiforme, and animalis. F. nucleatum subsp. polymorphum ATCC 10953 has been well characterized phenotypically and, in contrast to previously sequenced strains, is amenable to gene transfer. We sequenced and annotated the 2,429,698 bp genome of F. nucleatum subsp. polymorphum ATCC 10953. Plasmid pFN3 from the strain was also sequenced and analyzed. When compared to the other two available fusobacterial genomes (F. nucleatum subsp. nucleatum, and F. nucleatum subsp. vincentii) 627 open reading frames unique …


Ligand-Signaled Upregulation Of Enterococcus Faecalis Ace Transcription, A Mechanism For Modulating Host-E Faecalis Interaction, Sreedhar R Nallapareddy, Barbara E Murray Sep 2006

Ligand-Signaled Upregulation Of Enterococcus Faecalis Ace Transcription, A Mechanism For Modulating Host-E Faecalis Interaction, Sreedhar R Nallapareddy, Barbara E Murray

Journal Articles

Enterococcus faecalis, the third most frequent cause of bacterial endocarditis, appears to be equipped with diverse surface-associated proteins showing structural-fold similarity to the immunoglobulin-fold family of staphylococcal adhesins. Among the putative E. faecalis surface proteins, the previously characterized adhesin Ace, which shows specific binding to collagen and laminin, was detectable in surface protein preparations only after growth at 46 degrees C, mirroring the finding that adherence was observed in 46 degrees C, but not 37 degrees C, grown E. faecalis cultures. To elucidate the influence of different growth and host parameters on ace expression, we investigated ace expression using E. …


Role Of A2b Adenosine Receptor Signaling In Adenosine-Dependent Pulmonary Inflammation And Injury, Chun-Xiao Sun, Hongyan Zhong, Amir Mohsenin, Eva Morschl, Janci L Chunn, Jose G Molina, Luiz Belardinelli, Dewan Zeng, Michael R Blackburn Aug 2006

Role Of A2b Adenosine Receptor Signaling In Adenosine-Dependent Pulmonary Inflammation And Injury, Chun-Xiao Sun, Hongyan Zhong, Amir Mohsenin, Eva Morschl, Janci L Chunn, Jose G Molina, Luiz Belardinelli, Dewan Zeng, Michael R Blackburn

Journal Articles

Adenosine has been implicated in the pathogenesis of chronic lung diseases such as asthma and chronic obstructive pulmonary disease. In vitro studies suggest that activation of the A2B adenosine receptor (A2BAR) results in proinflammatory and profibrotic effects relevant to the progression of lung diseases; however, in vivo data supporting these observations are lacking. Adenosine deaminase-deficient (ADA-deficient) mice develop pulmonary inflammation and injury that are dependent on increased lung adenosine levels. To investigate the role of the A2BAR in vivo, ADA-deficient mice were treated with the selective A2BAR antagonist CVT-6883, and pulmonary inflammation, fibrosis, and airspace integrity were assessed. Untreated and …


Transcriptional Regulation Of The Borrelia Burgdorferi Antigenically Variable Vlse Surface Protein, Tomasz Bykowski, Kelly Babb, Kate Von Lackum, Sean P Riley, Steven J Norris, Brian Stevenson Jul 2006

Transcriptional Regulation Of The Borrelia Burgdorferi Antigenically Variable Vlse Surface Protein, Tomasz Bykowski, Kelly Babb, Kate Von Lackum, Sean P Riley, Steven J Norris, Brian Stevenson

Journal Articles

The Lyme disease agent Borrelia burgdorferi can persistently infect humans and other animals despite host active immune responses. This is facilitated, in part, by the vls locus, a complex system consisting of the vlsE expression site and an adjacent set of 11 to 15 silent vls cassettes. Segments of nonexpressed cassettes recombine with the vlsE region during infection of mammalian hosts, resulting in combinatorial antigenic variation of the VlsE outer surface protein. We now demonstrate that synthesis of VlsE is regulated during the natural mammal-tick infectious cycle, being activated in mammals but repressed during tick colonization. Examination of cultured B. …


Constitutive Nf-Kappab And Nfat Activation Leads To Stimulation Of The Blys Survival Pathway In Aggressive B-Cell Lymphomas., Lingchen Fu, Yen-Chiu Lin-Lee, Lan V Pham, Archito Tamayo, Linda Yoshimura, Richard J Ford Jun 2006

Constitutive Nf-Kappab And Nfat Activation Leads To Stimulation Of The Blys Survival Pathway In Aggressive B-Cell Lymphomas., Lingchen Fu, Yen-Chiu Lin-Lee, Lan V Pham, Archito Tamayo, Linda Yoshimura, Richard J Ford

Journal Articles

B-lymphocyte stimulator (BLyS), a relatively recently recognized member of the tumor necrosis factor ligand family (TNF), is a potent cell-survival factor expressed in many hematopoietic cells. BLyS binds to 3 TNF-R receptors, TACI, BCMA, BAFF-R, to regulate B-cell survival, differentiation, and proliferation. The mechanisms involved in BLYS gene expression and regulation are still incompletely understood. In this study, we examined BLYS gene expression, function, and regulation in B-cell non-Hodgkin lymphoma (NHL-B) cells. Our studies indicate that BLyS is constitutively expressed in aggressive NHL-B cells, including large B-cell lymphoma (LBCL) and mantle cell lymphoma (MCL), playing an important role in the …


Translational Regulation Of Nuclear Gene Cox4 Expression By Mitochondrial Content Of Phosphatidylglycerol And Cardiolipin In Saccharomyces Cerevisiae, Xuefeng Su, William Dowhan Feb 2006

Translational Regulation Of Nuclear Gene Cox4 Expression By Mitochondrial Content Of Phosphatidylglycerol And Cardiolipin In Saccharomyces Cerevisiae, Xuefeng Su, William Dowhan

Journal Articles

Previous results indicated that translation of four mitochondrion-encoded genes and one nucleus-encoded gene (COX4) is repressed in mutants (pgs1Delta) of Saccharomyces cerevisiae lacking phosphatidylglycerol and cardiolipin. COX4 translation was studied here using a mitochondrially targeted green fluorescence protein (mtGFP) fused to the COX4 promoter and its 5' and 3' untranslated regions (UTRs). Lack of mtGFP expression independent of carbon source and strain background was established to be at the translational level. The translational defect was not due to deficiency of mitochondrial respiratory function but was rather caused directly by the lack of phosphatidylglycerol and cardiolipin in mitochondrial membranes. Reintroduction of …


Construction Of Improved Temperature-Sensitive And Mobilizable Vectors And Their Use For Constructing Mutations In The Adhesin-Encoding Acm Gene Of Poorly Transformable Clinical Enterococcus Faecium Strains, Sreedhar R Nallapareddy, Kavindra V Singh, Barbara E Murray Jan 2006

Construction Of Improved Temperature-Sensitive And Mobilizable Vectors And Their Use For Constructing Mutations In The Adhesin-Encoding Acm Gene Of Poorly Transformable Clinical Enterococcus Faecium Strains, Sreedhar R Nallapareddy, Kavindra V Singh, Barbara E Murray

Journal Articles

Inactivation by allelic exchange in clinical isolates of the emerging nosocomial pathogen Enterococcus faecium has been hindered by lack of efficient tools, and, in this study, transformation of clinical isolates was found to be particularly problematic. For this reason, a vector for allelic replacement (pTEX5500ts) was constructed that includes (i) the pWV01-based gram-positive repAts replication region, which is known to confer a high degree of temperature intolerance, (ii) Escherichia coli oriR from pUC18, (iii) two extended multiple-cloning sites located upstream and downstream of one of the marker genes for efficient cloning of flanking regions for double-crossover mutagenesis, (iv) transcriptional terminator …