Medicine and Health Sciences Commons^™

The Synthetic Triterpenoid Cddo-Methyl Ester Modulates Microglial Activities, Inhibits Tnf Production, And Provides Dopaminergic Neuroprotection, Thi A. Tran, Melissa K. Mccoy, Michael B. Sporn, Malú G. Tansey

Dartmouth Scholarship

Recent animal and human studies implicate chronic activation of microglia in the progressive loss of CNS neurons. The inflammatory mechanisms that have neurotoxic effects and contribute to neurodegeneration need to be elucidated and specifically targeted without interfering with the neuroprotective effects of glial activities. Synthetic triterpenoid analogs of oleanolic acid, such as methyl-2-cyano-3,12-dioxooleana-1,9-dien-28-oate (CDDO-Me, RTA 402) have potent anti-proliferative and differentiating effects on tumor cells, and anti-inflammatory activities on activated macrophages. We hypothesized that CDDO-Me may be able to suppress neurotoxic microglial activities while enhancing those that promote neuronal survival. Therefore, the aims of our study were to identify specific …

Rest Maintains Self-Renewal And Pluripotency Of Embryonic Stem Cells, Sanjay K Singh, Mohamedi N Kagalwala, Jan Parker-Thornburg, Henry Adams, Sadhan Majumder

Faculty, Staff and Student Publications

The neuronal repressor REST (RE1-silencing transcription factor; also called NRSF) is expressed at high levels in mouse embryonic stem (ES) cells, but its role in these cells is unclear. Here we show that REST maintains self-renewal and pluripotency in mouse ES cells through suppression of the microRNA miR-21. We found that, as with known self-renewal markers, the level of REST expression is much higher in self-renewing mouse ES cells than in differentiating mouse ES (embryoid body, EB) cells. Heterozygous deletion of Rest (Rest+/-) and its short-interfering-RNA-mediated knockdown in mouse ES cells cause a loss of self-renewal-even when these cells are …

Cd73-Generated Adenosine Restricts Lymphocyte Migration Into Draining Lymph Nodes, Masahide Takedachi, Dongfeng Qu, Yukihiko Ebisuno, Hiroyuki Oohara, Michelle L Joachims, Stephanie T Mcgee, Emiko Maeda, Rodger P Mcever, Toshiyuki Tanaka, Masayuki Miyasaka, Shinya Murakami, Thomas Krahn, Michael R Blackburn, Linda F Thompson

Faculty, Staff and Student Publications

After an inflammatory stimulus, lymphocyte migration into draining lymph nodes increases dramatically to facilitate the encounter of naive T cells with Ag-loaded dendritic cells. In this study, we show that CD73 (ecto-5'-nucleotidase) plays an important role in regulating this process. CD73 produces adenosine from AMP and is expressed on high endothelial venules (HEV) and subsets of lymphocytes. Cd73(-/-) mice have normal sized lymphoid organs in the steady state, but approximately 1.5-fold larger draining lymph nodes and 2.5-fold increased rates of L-selectin-dependent lymphocyte migration from the blood through HEV compared with wild-type mice 24 h after LPS administration. Migration rates of …

Maternal Cocaine Administration In Mice Alters Dna Methylation And Gene Expression In Hippocampal Neurons Of Neonatal And Prepubertal Offspring, Svetlana I. Novikova, Fang He, Jie Bai, Nicholas J. Cutrufello, Michael S. Lidow, Ashiwel S. Undieh

College of Pharmacy Faculty Papers

Previous studies documented significant behavioral changes in the offspring of cocaine-exposed mothers. We now explore the hypothesis that maternal cocaine exposure could alter the fetal epigenetic machinery sufficiently to cause lasting neurochemical and functional changes in the offspring. Pregnant CD1 mice were administered either saline or 20 mg/kg cocaine twice daily on gestational days 8-19. Male pups from each of ten litters of the cocaine and control groups were analyzed at 3 (P3) or 30 (P30) days postnatum. Global DNA methylation, methylated DNA immunoprecipitation followed by CGI(2) microarray profiling and bisulfite sequencing, as well as quantitative real-time RT-PCR gene expression …

Ly2109761, A Novel Transforming Growth Factor Beta Receptor Type I And Type Ii Dual Inhibitor, As A Therapeutic Approach To Suppressing Pancreatic Cancer Metastasis, Davide Melisi, Satoshi Ishiyama, Guido M Sclabas, Jason B Fleming, Qianghua Xia, Giampaolo Tortora, James L Abbruzzese, Paul J Chiao

Faculty, Staff and Student Publications

Most pancreatic cancer patients present with inoperable disease or develop metastases after surgery. Conventional therapies are usually ineffective in treating metastatic disease. It is evident that novel therapies remain to be developed. Transforming growth factor beta (TGF-beta) plays a key role in cancer metastasis, signaling through the TGF-beta type I/II receptors (TbetaRI/II). We hypothesized that targeting TbetaRI/II kinase activity with the novel inhibitor LY2109761 would suppress pancreatic cancer metastatic processes. The effect of LY2109761 has been evaluated on soft agar growth, migration, invasion using a fibroblast coculture model, and detachment-induced apoptosis (anoikis) by Annexin V flow cytometric analysis. The efficacy …

Disruption Of C-Jun Reduces Cellular Migration And Invasion Through Inhibition Of C-Src And Hyperactivation Of Rock Ii Kinase., Xuanmao Jiao, Sanjay Katiyar, Manran Liu, Susette C Mueller, Michael P. Lisanti, Anping Li, Timothy G Pestell, Kongming Wu, Xiaoming Ju, Zhiping Li, Erwin F Wagner, Tatsuo Takeya, Chenguang Wang, Richard G Pestell

Kimmel Cancer Center Faculty Papers

The spread of metastatic tumors to different organs is associated with poor prognosis. The metastatic process requires migration and cellular invasion. The protooncogene c-jun encodes the founding member of the activator protein-1 family and is required for cellular proliferation and DNA synthesis in response to oncogenic signals and plays an essential role in chemical carcinogenesis. The role of c-Jun in cellular invasion remains to be defined. Genetic deletion of c-Jun in transgenic mice is embryonic lethal; therefore, transgenic mice encoding a c-Jun gene flanked by LoxP sites (c-jun(f/f)) were used. c-jun gene deletion reduced c-Src expression, hyperactivated ROCK II signaling, …

Trail Mediates Liver Injury By The Innate Immune System In The Bile Duct-Ligated Mouse., Alisan Kahraman, Fernando J. Barreyro, Steven F. Bronk, Nathan W. Werneburg, Justin L. Mott, Yuko Akazawa, Howard C Masuoka, Charles L Howe, Gregory J. Gores

Journal Articles: Biochemistry & Molecular Biology

The contribution of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a death ligand expressed by cells of the innate immune system, to cholestatic liver injury has not been explored. Our aim was to ascertain if TRAIL contributes to liver injury in the bile duct-ligated (BDL) mouse. C57/BL6 wild-type (wt), TRAIL heterozygote (TRAIL(+/-)), and TRAIL knockout (TRAIL(-/-)) mice were used for these studies. Liver injury and fibrosis were examined 7 and 14 days after BDL, respectively. Hepatic TRAIL messenger RNA (mRNA) was 6-fold greater in BDL animals versus sham-operated wt animals (P < 0.01). The increased hepatic TRAIL expression was accompanied by an increase in liver accumulation of natural killer 1.1 (NK 1.1)-positive NK and natural killer T (NKT) cells, the predominant cell types expressing TRAIL. Depletion of NK 1.1-positive cells reduced hepatic TRAIL mRNA expression and serum alanine aminotransferase (ALT) values. Consistent with a role for NK/NKT cells in this model of liver injury, stress ligands necessary for their recognition of target cells were also up-regulated in hepatocytes following BDL. Compared to sham-operated wt mice, BDL mice displayed a 13-fold increase in terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and an 11-fold increase in caspase 3/7-positive hepatocytes (P < 0.01). The number of TUNEL and caspase 3/7-positive cells was reduced by >80% in BDL TRAIL knockout animals (P < 0.05). Likewise, liver histology, number of bile infarcts, serum ALT values, hepatic fibrosis, and animal survival were also improved in BDL TRAIL(-/-) animals as compared to wt animals. Conclusion: These observations support a pivotal role for TRAIL in cholestatic liver injury mediated by NK 1.1-positive NK/NKT cells.

Excess Adenosine In Murine Penile Erectile Tissues Contributes To Priapism Via A2b Adenosine Receptor Signaling, Tiejuan Mi, Shahrzad Abbasi, Hong Zhang, Karen Uray, Janci L Chunn, Ling Wei Xia, Jose G Molina, Norman W Weisbrodt, Rodney E Kellems, Michael R Blackburn, Yang Xia

Faculty, Staff and Student Publications

Priapism, abnormally prolonged penile erection in the absence of sexual excitation, is associated with ischemia-mediated erectile tissue damage and subsequent erectile dysfunction. It is common among males with sickle cell disease (SCD), and SCD transgenic mice are an accepted model of the disorder. Current strategies to manage priapism suffer from a poor fundamental understanding of the molecular mechanisms underlying the disorder. Here we report that mice lacking adenosine deaminase (ADA), an enzyme necessary for the breakdown of adenosine, displayed unexpected priapic activity. ADA enzyme therapy successfully corrected the priapic activity both in vivo and in vitro, suggesting that it was …

Renin Inhibition Reduces Hypercholesterolemia-Induced Atherosclerosis In Mice, Hong Lu, Debra L. Rateri, David L. Feldman, Richard Charnigo, Akiyoshi Fukamizu, Junji Ishida, Elizabeth Grace Oesterling, Lisa A. Cassis, Alan Daugherty

Saha Cardiovascular Research Center Faculty Publications

The role of the renin angiotensin system (RAS) in atherosclerosis is complex because of the involvement of multiple peptides and receptors. Renin is the rate-limiting enzyme in the production of all angiotensin peptides. To determine the effects of renin inhibition on atherosclerosis, we administered the novel renin inhibitor aliskiren over a broad dose range to fat-fed LDL receptor-deficient (Ldlr^-/-) mice. Renin inhibition resulted in striking reductions of atherosclerotic lesion size in both the aortic arch and the root. Subsequent studies demonstrated that cultured macrophages expressed all components of the RAS. To determine the role of macrophage-derived angiotensin in …

Preimplantation Embryo Programming: Transcription, Epigenetics, And Culture Environment., Veronique Duranthon, Andrew J Watson, Patrick Lonergan

Obstetrics & Gynaecology Publications

Preimplantation development directs the formation of an implantation- or attachment-competent embryo so that metabolic interactions with the uterus can occur, pregnancy can be initiated, and fetal development can be sustained. The preimplantation embryo exhibits a form of autonomous development fueled by products provided by the oocyte and also from activation of the embryo's genome. Despite this autonomy, the preimplantation embryo is highly influenced by factors in the external environment and in extreme situations, such as those presented by embryo culture or nuclear transfer, the ability of the embryo to adapt to the changing environmental conditions or chromatin to become reprogrammed …

Fibulin-2 Is Dispensable For Mouse Development And Elastic Fiber Formation, Francois-Xavier Sicot, Takeshi Tsuda, Dessislava Markova, John Klement, Machiko Arita, Rui-Zhu Zhang, Te-Cheng Pan, Robert P. Mecham, David E. Birk, Mon-Li Chu

Department of Dermatology and Cutaneous Biology Faculty Papers

Fibulin-2 is an extracellular matrix protein belonging to the five-member fibulin family, of which two members have been shown to play essential roles in elastic fiber formation during development. Fibulin-2 interacts with two major constituents of elastic fibers, tropoelastin and fibrillin-1, in vitro and localizes to elastic fibers in many tissues in vivo. The protein is prominently expressed during morphogenesis of the heart and aortic arch vessels and at early stages of cartilage development. To examine its role in vivo, we generated mice that do not express the fibulin-2 gene (Fbln2) through homologous recombination of embryonic stem cells. Unexpectedly, the …

Trk: A Neuromodulator Of Age-Specific Behavioral And Neurochemical Responses To Cocaine In Mice., Michelle Niculescu, Shane A Perrine, Jonathan S Miller, Michelle E Ehrlich, Ellen M Unterwald

Farber Institute for Neuroscience Faculty Papers

Responses to psychostimulants vary with age, but the molecular etiologies of these differences are largely unknown. The goal of the present research was to identify age-specific behavioral and molecular adaptations to cocaine and to elucidate the mechanisms involved therein. Postweanling, periadolescent, and adult male CD-1 mice were exposed to cocaine (20 mg/kg) for 7 d. The rewarding effects of cocaine were assessed, as were the response to a Trk antagonist and the regulation of dopamine and cAMP-regulated phosphoprotein, 32 kDa (DARPP-32). Cocaine was rewarding in both periadolescent and adult mice using a conditioned place preference procedure. In contrast, postweanling mice …

Nitrated Alpha-Synuclein Immunity Accelerates Degeneration Of Nigral Dopaminergic Neurons., Eric J. Benner, Rebecca Banerjee, Ashley D. Reynolds, Simon Sherman, Vladimir M. Pisarev, Vladislav Tsiperson, Craig Nemachek, Pawel Ciborowski, Serge Przedborski, R. Lee Mosley, Howard Gendelman

Journal Articles: Eppley Institute

BACKGROUND: The neuropathology of Parkinson's disease (PD) includes loss of dopaminergic neurons in the substantia nigra, nitrated alpha-synuclein (N-alpha-Syn) enriched intraneuronal inclusions or Lewy bodies and neuroinflammation. While the contribution of innate microglial inflammatory activities to disease are known, evidence for how adaptive immune mechanisms may affect the course of PD remains obscure. We reasoned that PD-associated oxidative protein modifications create novel antigenic epitopes capable of peripheral adaptive T cell responses that could affect nigrostriatal degeneration.

METHODS AND FINDINGS: Nitrotyrosine (NT)-modified alpha-Syn was detected readily in cervical lymph nodes (CLN) from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxicated mice. Antigen-presenting cells within the CLN …

Targeting Nf-Kappab: A Promising Molecular Therapy In Inflammatory Arthritis., Jorge A. Roman-Blas, Sergio A. Jimenez

Scleroderma Center Faculty Papers

The nuclear factor-kappa B family of transcription factors is intimately involved in the regulation of the inflammatory responses that play a fundamental role in the damage of articular tissues. Thus, many studies have examined the important contributions of components of the NF-kappaB signaling pathways to the pathogenesis of various rheumatic diseases and their pharmacologic modulation. Currently available therapeutic agents including nonsteroidal anti-inflammatory drugs, corticosteroids, nutraceuticals, and disease-modifying antirheumatic drugs, as well as novel specific small-molecule inhibitors have been employed. In addition, promising nucleic acid-based strategies have shown encouraging results. However, further research will be needed before NF-kappaB-aimed strategies become an …

Novel Implications Of The Kallikrein-Kinin System In Diabetic Vasculopathy: A Proposed Role Of Prekallikrein In The Causation And Development Of Vascular Pathology In Diabetics, Rany Abdallah

MUSC Theses and Dissertations

Despite the clear association between diabetes and atherosclerotic vascular disease, the factors and mechanisms underlying the association between the two diseases are not well understood. Our preliminary studies, based on data obtained from the national Diabetes Control and Complication Trial/Epidemiology of Diabetes and Complications (DCCT/EDIC) cohort of type 1 diabetes subjects, suggest that diabetic atherosclerosis is linked to defects in the Kallikrein-Kinin System (KKS). Our research also found that apoliporotein E (ApoE) knockout mice, which have marked increase in total plasma cholesterol levels and a higher number of atherosclerotic lesions compared to wild type mice, have markedly higher plasma prekallikrein …

Sr-Bi Protects Against Endotoxemia In Mice Through Its Roles In Glucocorticoid Production And Hepatic Clearance, Lei Cai, Ailing Ji, Frederick C. De Beer, Lisa R. Tannock, Deneys R. Van Der Westhuyzen

Internal Medicine Faculty Publications

Septic shock results from an uncontrolled inflammatory response, mediated primarily by LPS. Cholesterol transport plays an important role in the host response to LPS, as LPS is neutralized by lipoproteins and adrenal cholesterol uptake is required for antiinflammatory glucocorticoid synthesis. In this study, we show that scavenger receptor B-I (SR-BI), an HDL receptor that mediates HDL cholesterol ester uptake into cells, is required for the normal antiinflammatory response to LPS-induced endotoxic shock. Despite elevated plasma HDL levels, SR-BI–null mice displayed an uncontrollable inflammatory cytokine response and a markedly higher lethality rate than control mice in response to LPS. In addition, …

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

Faculty, Staff and Student Publications

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 …

Elucidating A Normal Function Of Huntingtin By Functional And Microarray Analysis Of Huntingtin-Null Mouse Embryonic Fibroblasts., Hua Zhang, Sudipto Das, Quan-Zhen Li, Ioannis Dragatsis, Joyce Repa, Scott Zeitlin, György Hajnóczky, Ilya Bezprozvanny

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: The polyglutamine expansion in huntingtin (Htt) protein is a cause of Huntington's disease (HD). Htt is an essential gene as deletion of the mouse Htt gene homolog (Hdh) is embryonic lethal in mice. Therefore, in addition to elucidating the mechanisms responsible for polyQ-mediated pathology, it is also important to understand the normal function of Htt protein for both basic biology and for HD. RESULTS: To systematically search for a mouse Htt function, we took advantage of the Hdh +/- and Hdh-floxed mice and generated four mouse embryonic fibroblast (MEF) cells lines which contain a single copy of the Hdh …

Cyan Fluorescent Protein Expression In Ganglion And Amacrine Cells In A Thy1-Cfp Transgenic Mouse Retina, Iona D Raymond, Alejandro Vila, Uyen-Chi N Huynh, Nicholas C Brecha

Faculty, Staff and Student Publications

PURPOSE: To characterize cyan fluorescent protein (CFP) expression in the retina of the thy1-CFP (B6.Cg-Tg(Thy1-CFP)23Jrs/J) transgenic mouse line.

METHODS: CFP expression was characterized using morphometric methods and immunohistochemistry with antibodies to neurofilament light (NF-L), neuronal nuclei (NeuN), POU-domain protein (Brn3a) and calretinin, which immunolabel ganglion cells, and syntaxin 1 (HPC-1), glutamate decarboxylase 67 (GAD(67)), GABA plasma membrane transporter-1 (GAT-1), and choline acetyltransferase (ChAT), which immunolabel amacrine cells.

RESULTS: CFP was extensively expressed in the inner retina, primarily in the inner plexiform layer (IPL), ganglion cell layer (GCL), nerve fiber layer, and optic nerve. CFP fluorescent cell bodies were in all …

Application Of In Vivo Induced Antigen Technology (Iviat) To Bacillus Anthracis, Sean M Rollins, Amanda Peppercorn, John S Young, Melissa Drysdale, Andrea Baresch, Margaret V Bikowski, David A Ashford, Conrad P Quinn, Martin Handfield, Jeffrey D Hillman, C Rick Lyons, Theresa M Koehler, Stephen B Calderwood, Edward T Ryan

Faculty, Staff and Student Publications

In vivo induced antigen technology (IVIAT) is an immuno-screening technique that identifies bacterial antigens expressed during infection and not during standard in vitro culturing conditions. We applied IVIAT to Bacillus anthracis and identified PagA, seven members of a N-acetylmuramoyl-L-alanine amidase autolysin family, three P60 family lipoproteins, two transporters, spore cortex lytic protein SleB, a penicillin binding protein, a putative prophage holin, respiratory nitrate reductase NarG, and three proteins of unknown function. Using quantitative real-time PCR comparing RNA isolated from in vitro cultured B. anthracis to RNA isolated from BALB/c mice infected with virulent Ames strain B. anthracis, we confirmed induced …

Large Scale Variation In Enterococcus Faecalis Illustrated By The Genome Analysis Of Strain Og1rf, Agathe Bourgogne, Danielle A Garsin, Xiang Qin, Kavindra V Singh, Jouko Sillanpaa, Shailaja Yerrapragada, Yan Ding, Shannon Dugan-Rocha, Christian Buhay, Hua Shen, Guan Chen, Gabrielle Williams, Donna Muzny, Arash Maadani, Kristina A Fox, Jason Gioia, Lei Chen, Yue Shang, Cesar A Arias, Sreedhar R Nallapareddy, Meng Zhao, Vittal P Prakash, Shahreen Chowdhury, Huaiyang Jiang, Richard A Gibbs, Barbara E Murray, Sarah K Highlander, George M Weinstock

Faculty, Staff and Student Publications

BACKGROUND: Enterococcus faecalis has emerged as a major hospital pathogen. To explore its diversity, we sequenced E. faecalis strain OG1RF, which is commonly used for molecular manipulation and virulence studies.

RESULTS: The 2,739,625 base pair chromosome of OG1RF was found to contain approximately 232 kilobases unique to this strain compared to V583, the only publicly available sequenced strain. Almost no mobile genetic elements were found in OG1RF. The 64 areas of divergence were classified into three categories. First, OG1RF carries 39 unique regions, including 2 CRISPR loci and a new WxL locus. Second, we found nine replacements where a sequence …

Mice Deficient In Involucrin, Envoplakin, And Periplakin Have A Defective Epidermal Barrier., Lisa M Sevilla, Rachida Nachat, Karen R Groot, John F Klement, Jouni Uitto, Philippe Djian, Arto Määttä, Fiona M Watt

Department of Dermatology and Cutaneous Biology Faculty Papers

The cornified envelope is assembled from transglutaminase cross-linked proteins and lipids in the outermost epidermal layers and is essential for skin barrier function. Involucrin, envoplakin, and periplakin form the protein scaffold on which the envelope assembles. To examine their combined function, we generated mice deficient in all three genes. The triple knockouts have delayed embryonic barrier formation and postnatal hyperkeratosis (abnormal accumulation of cornified cells) resulting from impaired desquamation. Cornified envelopes form but are ultrastructurally abnormal, with reduced lipid content and decreased mechanical integrity. Expression of proteases is reduced and the protease inhibitor, serpina1b, is highly upregulated, resulting in defective …

A Novel Inhibitory Mechanism Of Mitochondrion-Dependent Apoptosis By A Herpesviral Protein, Pinghui Feng, Chengyu Liang, Young C. Shin, Xiaofei E, Weijun Zhang, Robyn Gravel, Ting-Ting Wu, Ren Sun, Edward Usherwood, Jae U. Jung

Dartmouth Scholarship

Upon viral infection, cells undergo apoptosis as a defense against viral replication. Viruses, in turn, have evolved elaborate mechanisms to subvert apoptotic processes. Here, we report that a novel viral mitochondrial anti-apoptotic protein (vMAP) of murine gamma-herpesvirus 68 (gammaHV-68) interacts with Bcl-2 and voltage-dependent anion channel 1 (VDAC1) in a genetically separable manner. The N-terminal region of vMAP interacted with Bcl-2, and this interaction markedly increased not only Bcl-2 recruitment to mitochondria but also its avidity for BH3-only pro-apoptotic proteins, thereby suppressing Bax mitochondrial translocation and activation. In addition, the central and C-terminal hydrophobic regions of vMAP interacted with VDAC1. …

Human Tob, An Antiproliferative Transcription Factor, Is A Poly(A)-Binding Protein-Dependent Positive Regulator Of Cytoplasmic Mrna Deadenylation, Nader Ezzeddine, Tsung-Cheng Chang, Wenmiao Zhu, Akio Yamashita, Chyi-Ying A Chen, Zhenping Zhong, Yukiko Yamashita, Dinghai Zheng, Ann-Bin Shyu

Faculty, Staff and Student Publications

In mammalian cells, mRNA decay begins with deadenylation, which involves two consecutive phases mediated by the PAN2-PAN3 and the CCR4-CAF1 complexes, respectively. The regulation of the critical deadenylation step and its relationship with RNA-processing bodies (P-bodies), which are thought to be a site where poly(A)-shortened mRNAs get degraded, are poorly understood. Using the Tet-Off transcriptional pulsing approach to investigate mRNA decay in mouse NIH 3T3 fibroblasts, we found that TOB, an antiproliferative transcription factor, enhances mRNA deadenylation in vivo. Results from glutathione S-transferase pull-down and coimmunoprecipitation experiments indicate that TOB can simultaneously interact with the poly(A) nuclease complex CCR4-CAF1 and …

Relative Contributions Of Enterococcus Faecalis Og1rf Sortase-Encoding Genes, Srta And Bps (Srtc), To Biofilm Formation And A Murine Model Of Urinary Tract Infection, Kelvin D Kemp, Kavindra V Singh, Sreedhar R Nallapareddy, Barbara E Murray

Faculty, Staff and Student Publications

Deletion mutants of the two sortase genes of Enterococcus faecalis OG1RF were constructed. srtC (renamed here bps for biofilm and pilus-associated sortase) was previously shown to be necessary for the production of Ebp pili and important for biofilm formation and endocarditis. Here, we report that a srtA deletion mutant showed a small (5%) yet significant (P = 0.037) reduction in biofilm relative to OG1RF, while a DeltasrtA Deltabps double mutant showed a much greater reduction (74% versus OG1RF and 44% versus the Deltabps mutant). In a murine urinary tract infection (UTI), the 50% infective doses of both the DeltasrtA Deltabps …

Osteopontin Mediates Obesity-Induced Adipose Tissue Macrophage Infiltration And Insulin Resistance In Mice, Takashi Nomiyama, Diego Perez-Tilve, Daisuke Ogawa, Florence Gizard, Yue Zhao, Elizabeth B. Heywood, Karrie L. Jones, Ryuzo Kawamori, Lisa A. Cassis, Matthias H. Tschöp, Dennis Bruemmer

Internal Medicine Faculty Publications

Obesity is associated with a state of chronic, low-grade inflammation characterized by abnormal cytokine production and macrophage infiltration into adipose tissue, which may contribute to the development of insulin resistance. During immune responses, tissue infiltration by macrophages is dependent on the expression of osteopontin, an extracellular matrix protein and proinflammatory cytokine that promotes monocyte chemotaxis and cell motility. In the present study, we used a murine model of diet-induced obesity to examine the role of osteopontin in the accumulation of adipose tissue macrophages and the development of insulin resistance during obesity. Mice exposed to a high-fat diet exhibited increased plasma …

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

Faculty, Staff and Student Publications

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 …

Mutations In The Cofilin Partner Aip1/Wdr1 Cause Autoinflammatory Disease And Macrothrombocytopenia, Benjamin T Kile, Athanasia D Panopoulos, Roslynn A Stirzaker, Douglas F Hacking, Lubna H Tahtamouni, Tracy A Willson, Lisa A Mielke, Katya J Henley, Jian-Guo Zhang, Ian P Wicks, William S Stevenson, Paquita Nurden, Stephanie S Watowich, Monica J Justice

Faculty, Staff and Student Publications

A pivotal mediator of actin dynamics is the protein cofilin, which promotes filament severing and depolymerization, facilitating the breakdown of existing filaments, and the enhancement of filament growth from newly created barbed ends. It does so in concert with actin interacting protein 1 (Aip1), which serves to accelerate cofilin's activity. While progress has been made in understanding its biochemical functions, the physiologic processes the cofilin/Aip1 complex regulates, particularly in higher organisms, are yet to be determined. We have generated an allelic series for WD40 repeat protein 1 (Wdr1), the mammalian homolog of Aip1, and report that reductions in Wdr1 function …

All-Trans Retinoic Acid Mediates Enhanced T Reg Cell Growth, Differentiation, And Gut Homing In The Face Of High Levels Of Co-Stimulation, Micah J. Benson, Karina Pino-Lagos, Mario Rosemblatt, Randolph J. Noelle

Dartmouth Scholarship

We demonstrate that all-trans retinoic acid (RA) induces FoxP3(+) adaptive T regulatory cells (A-Tregs) to acquire a gut-homing phenotype (alpha 4 beta 7(+) CC chemokine receptor 9(+)) and the capacity to home to the lamina propria of the small intestine. Under conditions that favor the differentiation of A-Tregs (transforming growth factor-beta1 and interleukin 2) in vitro, the inclusion of RA induces nearly all activated CD4(+) T cells to express FoxP3 and greatly increases the accumulation of these cells. In the absence of RA, A-Treg differentiation is abruptly impaired by proficient antigen presenting cells or through direct co-stimulation. In the presence …

Molecular Determinants Of Mg2+ And Ca2+ Permeability And Ph Sensitivity In Trpm6 And Trpm7*S, Mingjiang Li, Jianyang Du, Jianmin Jiang, William J. Ratzan, Li-Ting Su, Loren W. Runnels, Lixia Yue

UCHC Articles - Research

The channel kinases TRPM6 and TRPM7 have recently been discovered to play important roles in Mg²⁺ and Ca²⁺ homeostasis, which is critical to both human health and cell viability. However, the molecular basis underlying these channels’ unique Mg²⁺ and Ca²⁺ permeability and pH sensitivity remains unknown. Here we have created a series of amino acid substitutions in the putative pore of TRPM7 to evaluate the origin of the permeability of the channel and its regulation by pH. Two mutants of TRPM7, E1047Q and E1052Q, produced dramatic changes in channel properties. The I–V relations of E1052Q and …