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388 A Structure Of Cytoplasmic Polyhedrosis Virus By Cryo-Electron Microscopy, Xuekui Yu, Lei Jin, Z Hong Zhou

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Cytoplasmic polyhedrosis virus (CPV) is unique within the Reoviridae family in having a turreted single-layer capsid contained within polyhedrin inclusion bodies, yet being fully capable of cell entry and endogenous RNA transcription. Biochemical data have shown that the amino-terminal 79 residues of the CPV turret protein (TP) is sufficient to bring CPV or engineered proteins into the polyhedrin matrix for micro-encapsulation. Here we report the three-dimensional structure of CPV at 3.88 A resolution using single-particle cryo-electron microscopy. Our map clearly shows the turns and deep grooves of alpha-helices, the strand separation in beta-sheets, and densities for loops and many bulky …

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

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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 …

Diviva Is Required For Polar Growth In The Mreb-Lacking Rod-Shaped Actinomycete Corynebacterium Glutamicum, Michal Letek, Efrén Ordóñez, José Vaquera, William Margolin, Klas Flärdh, Luis M Mateos, José A Gil

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The actinomycete Corynebacterium glutamicum grows as rod-shaped cells by zonal peptidoglycan synthesis at the cell poles. In this bacterium, experimental depletion of the polar DivIVA protein (DivIVA(Cg)) resulted in the inhibition of polar growth; consequently, these cells exhibited a coccoid morphology. This result demonstrated that DivIVA is required for cell elongation and the acquisition of a rod shape. DivIVA from Streptomyces or Mycobacterium localized to the cell poles of DivIVA(Cg)-depleted C. glutamicum and restored polar peptidoglycan synthesis, in contrast to DivIVA proteins from Bacillus subtilis or Streptococcus pneumoniae, which localized at the septum of C. glutamicum. This confirmed that DivIVAs …

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

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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 …

Enterococcus Faecalis Pcfc, A Spatially Localized Substrate Receptor For Type Iv Secretion Of The Pcf10 Transfer Intermediate, Yuqing Chen, Xiaolin Zhang, Dawn Manias, Hye-Jeong Yeo, Gary M Dunny, Peter J Christie

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Upon sensing of peptide pheromone, Enterococcus faecalis efficiently transfers plasmid pCF10 through a type IV secretion (T4S) system to recipient cells. The PcfF accessory factor and PcfG relaxase initiate transfer by catalyzing strand-specific nicking at the pCF10 origin of transfer sequence (oriT). Here, we present evidence that PcfF and PcfG spatially coordinate docking of the pCF10 transfer intermediate with PcfC, a membrane-bound putative ATPase related to the coupling proteins of gram-negative T4S machines. PcfC and PcfG fractionated with the membrane and PcfF with the cytoplasm, yet all three proteins formed several punctate foci at the peripheries of pheromone-induced cells as …

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

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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 …

Drug Metabolism In Human Brain: High Levels Of Cytochrome P4503a43 In Brain And Metabolism Of Anti-Anxiety Drug Alprazolam To Its Active Metabolite, Varsha Agarwal, Reddy P. Kommaddi, Khader Valli, Daniel Ryder, Thomas M. Hyde, Joel E. Kleinman, Henry W. Strobel, Vijayalakshmi Ravindranath

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Cytochrome P450 (P450) is a super-family of drug metabolizing enzymes. P450 enzymes have dual function; they can metabolize drugs to pharmacologically inactive metabolites facilitating their excretion or biotransform them to pharmacologically active metabolites which may have longer half-life than the parent drug. The variable pharmacological response to psychoactive drugs typically seen in population groups is often not accountable by considering dissimilarities in hepatic metabolism. Metabolism in brain specific nuclei may play a role in pharmacological modulation of drugs acting on the CNS and help explain some of the diverse response to these drugs seen in patient population. P450 enzymes are …

The Effect Of Dexmedetomidine On The Mini-Cog Score And High-Mobility Group Box 1 Levels In Elderly Patients With Postoperative Neurocognitive Disorders Undergoing Orthopedic Surgery, Joan M Mastrobattista, Mark A Klebanoff, J Christopher Carey, John C Hauth, Cora A Macpherson, J Ernest, Margaret Cotroneo, Kenneth J Leveno, Ronald Wapner, Michael Varner, Jay D Iams, Atef Moawad, Baha M Sibai, Menachem Miodovnik, Mitchell Dombrowski, Mary J O'Sullivan, J Peter Vandorsten, Oded Langer

Faculty, Staff and Student Publications

Our objective was to determine the effect of body mass index (BMI) on response to bacterial vaginosis (BV) treatment. A secondary analysis was conducted of two multicenter trials of therapy for BV and TRICHOMONAS VAGINALIS. Gravida were screened for BV between 8 and 22 weeks and randomized between 16 and 23 weeks to metronidazole or placebo. Of 1497 gravida with asymptomatic BV and preconceptional BMI, 738 were randomized to metronidazole; BMI was divided into categories: < 25, 25 to 29.9, and > or = 30. Rates of BV persistence at follow-up were compared using the Mantel-Haenszel chi square. Multiple logistic regression was used to evaluate the effect …

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 …

Verb Generation In Children With Spina Bifida, Maureen Dennis, Derryn Jewell, Ross Hetherington, Christine Burton, Michael E. Brandt, Susan E. Blaser, Jack M Fletcher

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We investigated verb generation in children with spina bifida meningomyelocele (SBM; n = 55) and in typically developing controls (n = 32). Participants completed 6 blocks (40 trials each) of a task requiring them to produce a semantically related verb in response to a target noun and an additional 40 trials on which they were simply required to read target nouns aloud. After controlling for reading response time, groups did not differ significantly in verb generation response time or learning. Children with SBM produced more non-verb errors than controls and tended to repeat their mistakes over blocks. Verb generation performance …

Unique Structures In A Tumor Herpesvirus Revealed By Cryo-Electron Tomography And Microscopy, Wei Dai, Qingmei Jia, Eric Bortz, Sanket Shah, Jun Liu, Ivo Atanasov, Xudong Li, Kenneth A Taylor, Ren Sun, Z Hong Zhou

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Gammaherpesviruses, including the human pathogens Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus, are causative agents of lymphomas and other malignancies. The structural characterization of these viruses has been limited due to difficulties in obtaining adequate amount of virion particles. Here we report the first three-dimensional structural characterization of a whole gammaherpesvirus virion by an emerging integrated approach of cryo-electron tomography combined with single-particle cryo-electron microscopy, using murine gammaherpesvirus-68 (MHV-68) as a model system. We found that the MHV-68 virion consists of distinctive envelope and tegument compartments, and a highly conserved nucleocapsid. Two layers of tegument are identified: an inner tegument layer …

Cryo-Electron Tomography Of Kaposi's Sarcoma-Associated Herpesvirus Capsids Reveals Dynamic Scaffolding Structures Essential To Capsid Assembly And Maturation, Binbin Deng, Christine M O'Connor, Dean H Kedes, Z Hong Zhou

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Kaposi's sarcoma-associated herpesvirus (KSHV) is a recently discovered DNA tumor virus that belongs to the gamma-herpesvirus subfamily. Though numerous studies on KSHV and other herpesviruses, in general, have revealed much about their multilayered organization and capsid structure, the herpesvirus capsid assembly and maturation pathway remains poorly understood. Structural variability or irregularity of the capsid internal scaffolding core and the lack of adequate tools to study such structures have presented major hurdles to earlier investigations employing more traditional cryo-electron microscopy (cryoEM) single particle reconstruction. In this study, we used cryo-electron tomography (cryoET) to obtain 3D reconstructions of individual KSHV capsids, allowing …

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

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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

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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 …

Focal White Matter Changes In Spasmodic Dysphonia: A Combined Diffusion Tensor Imaging And Neuropathological Study, Kristina Simonyan, Fernanda Tovar-Moll, John Ostuni, Mark Hallett, Victor F Kalasinsky, Michael R Lewin-Smith, Elisabeth J Rushing, Alexander O Vortmeyer, Christy L Ludlow

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Spasmodic dysphonia is a neurological disorder characterized by involuntary spasms in the laryngeal muscles during speech production. Although the clinical symptoms are well characterized, the pathophysiology of this voice disorder is unknown. We describe here, for the first time to our knowledge, disorder-specific brain abnormalities in these patients as determined by a combined approach of diffusion tensor imaging (DTI) and postmortem histopathology. We used DTI to identify brain changes and to target those brain regions for neuropathological examination. DTI showed right-sided decrease of fractional anisotropy in the genu of the internal capsule and bilateral increase of overall water diffusivity in …

Molecular Studies In Treponema Pallidum Evolution: Toward Clarity?, Connie J. Mulligan, Steven J. Norris, Sheila A. Lukehart

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No abstract provided.

Repeat Length And Rna Expression Level Are Not Primary Determinants In Cug Expansion Toxicity In Drosophila Models, Gwenn Le Mée, Nader Ezzeddine, Michèle Capri, Ounissa Aït-Ahmed

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Evidence for an RNA gain-of-function toxicity has now been provided for an increasing number of human pathologies. Myotonic dystrophies (DM) belong to a class of RNA-dominant diseases that result from RNA repeat expansion toxicity. Specifically, DM of type 1 (DM1), is caused by an expansion of CUG repeats in the 3'UTR of the DMPK protein kinase mRNA, while DM of type 2 (DM2) is linked to an expansion of CCUG repeats in an intron of the ZNF9 transcript (ZNF9 encodes a zinc finger protein). In both pathologies the mutant RNA forms nuclear foci. The mechanisms that underlie the RNA pathogenicity …

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

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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 …

Multifactor Effects And Evidence Of Potential Interaction Between Complement Factor H Y402h And Loc387715 A69s In Age-Related Macular Degeneration, Sanna P. Seitsonen, Päivi Onkamo, Gang Peng, Momiao Xiong, Petri V. Tommila, Päivi H. Ranta, Juha M. Holopainen, Jukka A. Moilanen, Tapani Palosaari, Kai Kaarniranta, Seppo Meri, Ilkka R. Immonen, Irma E. Järvelä

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BACKGROUND: Variants in the complement cascade genes and the LOC387715/HTRA1, have been widely reported to associate with age-related macular degeneration (AMD), the most common cause of visual impairment in industrialized countries. METHODS/PRINCIPAL FINDINGS: We investigated the association between the LOC387715 A69S and complement component C3 R102G risk alleles in the Finnish case-control material and found a significant association with both variants (OR 2.98, p = 3.75 x 10(-9); non-AMD controls and OR 2.79, p = 2.78 x 10(-19), blood donor controls and OR 1.83, p = 0.008; non-AMD controls and OR 1.39, p = 0.039; blood donor controls), respectively. Previously, …

Differential Dynamic Properties Of Scleroderma Fibroblasts In Response To Perturbation Of Environmental Stimuli, Momiao Xiong, Frank C. Arnett, Xinjian Guo, Hao Xiong, Xiaodong Zhou

Faculty, Staff and Student Publications

Diseases are believed to arise from dysregulation of biological systems (pathways) perturbed by environmental triggers. Biological systems as a whole are not just the sum of their components, rather ever-changing, complex and dynamic systems over time in response to internal and external perturbation. In the past, biologists have mainly focused on studying either functions of isolated genes or steady-states of small biological pathways. However, it is systems dynamics that play an essential role in giving rise to cellular function/dysfunction which cause diseases, such as growth, differentiation, division and apoptosis. Biological phenomena of the entire organism are not only determined by …

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

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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 …

The Role Of Sse1 In The De Novo Formation And Variant Determination Of The [Psi+] Prion, Jaou-Chen Huang

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In several species, a family of nuclear receptors, the peroxisome proliferator-activated receptors (PPARs) composed of three isotypes, is expressed in somatic cells and germ cells of the ovary as well as the testis. Invalidation of these receptors in mice or stimulation of these receptors in vivo or in vitro showed that each receptor has physiological roles in the gamete maturation or the embryo development. In addition, synthetic PPAR gamma ligands are recently used to induce ovulation in women with polycystic ovary disease. These results reveal the positive actions of PPAR in reproduction. On the other hand, xenobiotics molecules (in herbicides, …

Genes In Glucose Metabolism And Association With Spina Bifida, Christina M Davidson, Hope Northrup, Terri M King, Jack M Fletcher, Irene Townsend, Gayle H Tyerman, Kit Sing Au

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The authors test single nucleotide polymorphisms (SNPs) in coding sequences of 12 candidate genes involved in glucose metabolism and obesity for associations with spina bifida. Genotyping was performed on 507 children with spina bifida and their parents plus anonymous control DNAs from Hispanic and Caucasian individuals. The transmission disequilibrium test was performed to test for genetic associations between transmission of alleles and spina bifida in the offspring (P < .05). A statistically significant association between Lys481 of HK1 (G allele), Arg109Lys of LEPR (G allele), and Pro196 of GLUT1 (A allele) was found ( P = .019, .039, and .040, respectively). Three SNPs on 3 genes involved with glucose metabolism and obesity may be associated with increased susceptibility to spina bifida.

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

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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

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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 …

Neurogranin Controls The Spatiotemporal Pattern Of Postsynaptic Ca2+/Cam Signaling, Yoshihisa Kubota, John A Putkey, M Neal Waxham

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Neurogranin (Ng) is a postsynaptic IQ-motif containing protein that accelerates Ca(2+) dissociation from calmodulin (CaM), a key regulator of long-term potentiation and long-term depression in CA1 pyramidal neurons. The exact physiological role of Ng, however, remains controversial. Two genetic knockout studies of Ng showed opposite outcomes in terms of the induction of synaptic plasticity. To understand its function, we test the hypothesis that Ng could regulate the spatial range of action of Ca(2+)/CaM based on its ability to accelerate the dissociation of Ca(2+) from CaM. Using a mathematical model constructed on the known biochemistry of Ng, we calculate the cycle …

Wingless Activity In The Precursor Cells Specifies Neuronal Migratory Behavior In The Drosophila Nerve Cord, Krishna Moorthi Bhat

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Neurons and their precursor cells are formed in different regions within the developing CNS, but they migrate and occupy very specific sites in the mature CNS. The ultimate position of neurons is crucial for establishing proper synaptic connectivity in the brain. In Drosophila, despite its extensive use as a model system to study neurogenesis, we know almost nothing about neuronal migration or its regulation. In this paper, I show that one of the most studied neuronal pairs in the Drosophila nerve cord, RP2/sib, has a complicated migratory route. Based on my studies on Wingless (Wg) signaling, I report that the …

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

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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 …

The Routine Use Of Preoperative Non-Contrast Chest Computerized Tomography And Carotid Arteries Doppler Prior To Cardiac Surgery, Qing Fan, Kyung-Won Park, Zhiqiang Du, Kevin A Morano, Liming Li

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Yeast prions are a group of non-Mendelian genetic elements transmitted as altered and self-propagating conformations. Extensive studies in the last decade have provided valuable information on the mechanisms responsible for yeast prion propagation. How yeast prions are formed de novo and what cellular factors are required for determining prion "strains" or variants--a single polypeptide capable of existing in multiple conformations to result in distinct heritable phenotypes--continue to defy our understanding. We report here that Sse1, the yeast ortholog of the mammalian heat-shock protein 110 (Hsp110) and a nucleotide exchange factor for Hsp70 proteins, plays an important role in regulating [PSI+] …

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

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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 …