Medical Sciences Commons^™

Direct Inhibition Of Cdk9 Blocks Hiv-1 Replication Without Preventing T Cell Activation In Primary Human Peripheral Blood Lymphocytes, Dominic Salerno, Muneer G Hasham, Renee Marshall Demarest, Judit Garriga, Alexander Y Tsygankov, Xavier Graña

Rowan-Virtua School of Osteopathic Medicine Departmental Research

HIV-1 transcription is essential for the virus replication cycle. HIV-1 Tat is a viral transactivator that strongly stimulates the processivity of RNA polymerase II (RNAPII) via recruitment of the cyclin T1/CDK9 positive transcription elongation factor, which phosphorylates the C-terminal domain (CTD) of RNAPII. Consistently, HIV-1 replication in transformed cells is very sensitive to direct CDK9 inhibition. Thus, CDK9 could be a potential target for anti-HIV-1 therapy. A clearer understanding of the requirements for CDK9 activity in primary human T cells is needed to assess whether the CDK9-dependent step in HIV-1 transcription can be targeted clinically. We have investigated the effects …

Mir-29 Regulates Mcl-1 Protein Expression And Apoptosis., Justin L. Mott, Shogo Kobayashi, Steven F. Bronk, Gregory J. Gores

Journal Articles: Biochemistry & Molecular Biology

Cellular expression of Mcl-1, an anti-apoptotic Bcl-2 family member, is tightly regulated. Recently, Bcl-2 expression was shown to be regulated by microRNAs, small endogenous RNA molecules that regulate protein expression through sequence-specific interaction with messenger RNA. By analogy, we reasoned that Mcl-1 expression may also be regulated by microRNAs. We chose human immortalized, but non-malignant, H69 cholangiocyte and malignant KMCH cholangiocarcinoma cell lines for these studies, because Mcl-1 is dysregulated in cells with the malignant phenotype. By in silico analysis, we identified a putative target site in the Mcl-1 mRNA for the mir-29 family, and found that mir-29b was highly …

Recent Advances In Cancer Stem/Progenitor Cell Research: Therapeutic Implications For Overcoming Resistance To The Most Aggressive Cancers., M. Mimeault, Ralph Hauke, Parmender P. Mehta, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

Overcoming intrinsic and acquired resistance of cancer stem/progenitor cells to current clinical treatments represents a major challenge in treating and curing the most aggressive and metastatic cancers. This review summarizes recent advances in our understanding of the cellular origin and molecular mechanisms at the basis of cancer initiation and progression as well as the heterogeneity of cancers arising from the malignant transformation of adult stem/progenitor cells. We describe the critical functions provided by several growth factor cascades, including epidermal growth factor receptor (EGFR), platelet-derived growth factor receptor (PDGFR), stem cell factor (SCF) receptor (KIT), hedgehog and Wnt/beta-catenin signalling pathways that …

Human Muc4 Mucin Induces Ultra-Structural Changes And Tumorigenicity In Pancreatic Cancer Cells., N. Moniaux, P. Chaturvedi, G. C. Varshney, Jane L. Meza, J. F. Rodriguez-Sierra, J-P Aubert, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

MUC4 is a type-1 transmembrane glycoprotein and is overexpressed in many carcinomas. It is a heterodimeric protein of 930 kDa, composed of a mucin-type subunit, MUC4alpha, and a membrane-bound growth factor-like subunit, MUC4beta. MUC4 mRNA contains unique 5' and 3' coding sequences along with a large variable number of tandem repeat (VNTR) domain of 7-19 kb. A direct association of MUC4 overexpression has been established with the degree of invasiveness and poor prognosis of pancreatic cancer. To understand the precise role of MUC4 in pancreatic cancer, we engineered a MUC4 complementary DNA construct, mini-MUC4, whose deduced protein (320 kDa) is …

Molecular Mechanism Of Tetraspanin Cd9 Mediated Cell Motility, Jayaprakash Kotha

Theses and Dissertations (ETD)

CD9, a member of the tetraspanin superfamily of proteins participates in the regulation of cell adhesive functions such as cell migration. The mechanisms underlying CD9 mediated cell migration are not known. In the current study, we investigated the molecular basis for the CD9 promoted cell migration. Our findings show that the phosphatidylinositol-3 kinase (PI-3K) inhibitors, wortamannin and LY294002 inhibited CD9 promoted cell motility in Chinese hamster ovary (CHO) cells. In contrast, inhibitors targeting protein kinase C or mitogen-activated protein kinase had no effect on CD9 driven CHO cell motility. Furthermore, inhibition of PI-3K activity in CHO cells by dominant/negative PI-3K …

Alzheimer's Disease: Cholesterol, Membrane Rafts, Isoprenoids And Statins, Patrick C. Reid, Yasuomi Urano, Tatsuhiko Kodama, Takao Hamakubo

Dartmouth Scholarship

Alzheimer's disease (AD) is a heterogeneous neurodegenerative disorder and the most prevalent form of dementia worldwide. AD is characterized pathologically by amyloid-? plaques, neurofibrillary tangles and neuronal loss, and clinically by a progressive loss of cognitive abilities. At present, the fundamental molecular mechanisms underlying the disease are unclear and no treatment for AD is known. Epidemiological evidence continues to mount linking vascular diseases, such as hypertension and diabetes, and hypercholesterolaemia with an increased risk for developing AD. A growing amount of evidence suggests a mechanistic link between cholesterol metabolism in the brain and the formation of amyloid plaques in AD …

Cpg Hypomethylation In A Large Domain Encompassing The Embryonic Β-Like Globin Genes In Primitive Erythrocytes, Mei Hsu, Rodwell R. Mabaera, Christopher H. Lowrey, David I. K. Martin, Steven Fiering

Dartmouth Scholarship

There is little evidence addressing the role of CpG methylation in transcriptional control of genes that do not contain CpG islands. This is reflected in the ongoing debate about whether CpG methylation merely suppresses retroelements or if it also plays a role in developmental and tissue-specific gene regulation. The genes of the β-globin locus are an important model of mammalian developmental gene regulation and do not contain CpG islands. We have analyzed the methylation status of regions in the murine β-like globin locus in uncultured primitive and definitive erythroblasts and other cultured primary and transformed cell types. A large (∼20-kb) …

The Notch Regulator Maml1 Interacts With P53 And Functions As A Coactivator., Yongtong Zhao, Rebecca B. Katzman, Laurie M. Delmolino, Ishfaq Bhat, Ying Zhang, Channabasavaiah B. Gurumurthy, Aleksandra Germaniuk-Kurowska, Honey V. Reddi, Aharon Solomon, Mu-Sheng Zeng, Aisha Kung, Hui Ma, Qingshen Gao, Goberdhan Dimri, Adina Stanculescu, Lucio Miele, Lizi Wu, James D. Griffin, David E. Wazer, Hamid Band, Vimla Band

Journal Articles: Biochemistry & Molecular Biology

Members of the evolutionarily conserved Mastermind (MAM) protein family, including the three related mammalian Mastermind-like (MAML) proteins MAML1-3, function as crucial coactivators of Notch-mediated transcriptional activation. Given the recent evidence of cross-talk between the p53 and Notch signal transduction pathways, we have investigated whether MAML1 may also be a transcriptional coactivator of p53. Indeed, we show here that MAML1 is able to interact with p53. We show that MAML1-p53 interaction involves the N-terminal region of MAML1 and the DNA-binding domain of p53, and we use a chromatin immunoprecipitation assay to show that MAML1 is part of the activator complex that …

An Essential Role Of Human Ada3 In P53 Acetylation., Alo Nag, Aleksandra Germaniuk-Kurowska, Manjari Dimri, Michael A. Sassack, Channabasavaiah B. Gurumurthy, Qingshen Gao, Goberdhan Dimri, Hamid Band, Vimla Band

Journal Articles: Biochemistry & Molecular Biology

The p53 tumor suppressor protein functions as a critical component of genotoxic stress response by regulating the expression of effector gene products that control the fate of a cell following DNA damage. Unstressed cells maintain p53 at low levels through regulated degradation, and p53 levels and activity are rapidly elevated upon genotoxic stress. Biochemical mechanisms that control the levels and activity of p53 are therefore of great interest. We and others have recently identified hAda3 (human homologue of yeast alteration/deficiency in activation 3) as a p53-interacting protein and enhancer of p53 activity. Here, we show that endogenous levels of p53 …

Role Of Protein Kinase Phosphorylation On Sert Oligomerization: A Novel Mechanistic View, Eric Richard Buck

MUSC Theses and Dissertations

The serotonin transporter (SERT) is the primary mechanism for the termination of synaptic signaling. It is of clinical relevance because it is a high-affinity target for therapeutics such as anti-depressants (SSRIs) and drugs of abuse such as cocaine, amphetamine, and 3,4 methylenedioxymethamphetamine (ecstasy). It is also seen as a protein potentially involved in the etiology underlying disorders such as clinical depression, autism, anxiety-related disorders, obsessive compulsive disorder, and anorexia nervosa among others. SERT has also been found to be a target of protein kinases that exert their effects through phosphorylation. For example, activation of protein kinase C (PKC) decreases SERT …

Sustained Il-6/Stat-3 Signaling In Cholangiocarcinoma Cells Due To Socs-3 Epigenetic Silencing., Hajime Isomoto, Justin L. Mott, Shogo Kobayashi, Nathan W. Werneburg, Steve F. Bronk, Serge Haan, Gregory J. Gores

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND & AIMS: Interleukin 6 (IL-6)-mediated signal transducers and activators of transcription 3 (STAT-3) phosphorylation (activation) is aberrantly sustained in cholangiocarcinoma cells resulting in enhanced myeloid cell leukemia 1 (Mcl-1) expression and resistance to apoptosis. Because suppressor of cytokine signaling 3 (SOCS) controls the IL-6/STAT-3 signaling pathway by a classic feedback loop, the aims of this study were to examine SOCS-3 regulation in human cholangiocarcinoma.

METHODS: SOCS-3 expression was assessed in human cholangiocarcinoma tissue and the Mz-ChA-1 and CCLP1 human cholangiocarcinoma cell lines.

RESULTS: An inverse correlation was observed between phospho-STAT-3 and SOCS-3 protein expression in cholangiocarcinoma. In those cancers …

Su.32. Myelin-Specific Regulatory T Cells Accumulate In The Central Nervous System, But Fail To Suppress Pathogenic Effector T Cells At The Peak Of Autoimmune Inflammation [Abstract Only], Thomas Korn, Mohamed Oukka, Jay Reddy, Estelle Betelli, Amit Awasthi, Raymond Sobel, Kai Wucherpfennig, Vijay K. Kuchroo

Jay Reddy Publications

Treatment with ex vivo generated regulatory T cells (Treg) has been regarded as highly attractive therapeutic approach for autoimmune diseases. However, the dynamics and function of T-reg in autoimmunity are not well understood. Thus, we developed Foxp3gfp “knock-in” mice and myelin oligodendrocyte glycoprotein (MOG)35–55/IAb tetramers to track autoantigen-specific effector T cells (T-eff) and T-reg in vivo during experimental autoimmune encephalomyelitis, an animal model for multiple sclerosis. Following immunization with the encephalitogenic peptide MOG35–55 emulsified in complete Freund's adjuvant, MOG35–55-tetramer-reactive, Foxp3+ T-reg expanded in the peripheral lymphoid compartment and readily accumulated in the central nervous system (CNS), but did not prevent …

Androgen-Regulated Formation And Degradation Of Gap Junctions In Androgen-Responsive Human Prostate Cancer Cells., Shalini Mitra, Lakshmanan Annamalai, Souvik Chakraborty, Kristen E. Johnson, Xiao-Hong Song, Surinder K. Batra, Parmender P. Mehta

Journal Articles: Biochemistry & Molecular Biology

The constituent proteins of gap junctions, called connexins (Cxs), have a short half-life. Despite this, the physiological stimuli that control the assembly of Cxs into gap junctions and their degradation have remained poorly understood. We show here that in androgen-responsive human prostate cancer cells, androgens control the expression level of Cx32-and hence the extent of gap junction formation-post-translationally. In the absence of androgens, a major fraction of Cx32 is degraded presumably by endoplasmic reticulum-associated degradation, whereas in their presence, this fraction is rescued from degradation. We also show that Cx32 and Cx43 degrade by a similar mechanism. Thus, androgens regulate …

Multiple Domains In Siz Sumo Ligases Contribute To Substrate Selectivity., Alison Reindle, Irina Belichenko, Gwendolyn R Bylebyl, Xiaole L Chen, Nishant Gandhi, Erica S Johnson

Department of Biochemistry and Molecular Biology Faculty Papers

Saccharomyces cerevisiae contains two Siz/PIAS SUMO E3 ligases, Siz1 and Siz2/Nfi1, and one other known ligase, Mms21. Although ubiquitin ligases are highly substrate-specific, the degree to which SUMO ligases target distinct sets of substrates is unknown. Here we show that although Siz1 and Siz2 each have unique substrates in vivo, sumoylation of many substrates can be stimulated by either protein. Furthermore, in the absence of both Siz proteins, many of the same substrates are still sumoylated at low levels. Some of this residual sumoylation depends on MMS21. Siz1 targets its unique substrates through at least two distinct domains. Sumoylation of …

Binding Of Internalized Receptors To The Pdz Domain Of Gipc/Synectin Recruits Myosin Vi To Endocytic Vesicles, Samia N. Naccache, Tama Hasson, Arie Horowitz

Dartmouth Scholarship

Myosin VI (myo6) is the only actin-based molecular motor that translocates along actin filaments toward the minus end. Myo6 participates in two steps of endocytic trafficking; it is recruited to both clathrin-coated pits and to ensuing uncoated endocytic vesicles (UCV). Although there is evidence suggesting that the PDZ adaptor protein GIPC/synectin is involved in the association of myo6 with UCV, the recruitment mechanism is unknown. We show that GIPC/synectin is required for both internalization of cell surface receptors and for coupling of myo6 to UCV. This coupling occurs via a mechanism wherein engagement of the GIPC/synectin PDZ domain by C …

Desulfovibrio Desulfuricans G20 Tetraheme Cytochrome Structure At 1.5 A˚ And Cytochrome Interaction With Metal Complexes, Mrunalini Pattarkine, J J. Tanner, C A. Bottoms, Y H. Lee, Judy D. Wall

Faculty Works

The structure of the type I tetraheme cytochrome c3 from Desulfovibrio desulfuricans G20 was determined to 1.5 A˚ by X-ray crystallography. In addition to the oxidized form, the structure of the molybdate-bound form of the protein was determined from oxidized crystals soaked in sodium molybdate. Only small structural shifts were obtained with metal binding, consistent with the remarkable structural stability of this protein. In vitro experiments with pure cytochrome showed that molybdate could oxidize the reduced cytochrome, although not as rapidly as U(VI) present as uranyl acetate. Alterations in the overall conformation and thermostability of the metal-oxidized protein were investigated …

Linking Ligand-Induced Alterations In Androgen Receptor Structure To Differential Gene Expression: A First Step In The Rational Design Of Selective Androgen Receptor Modulators, Dmitri Kazmin, Tatiana Prytkova, C. Edgar Cook, Russell Wolfinger, Tzu-Ming Chu, David Beratan, J. D. Norris, Ching-Yi Chang, Donald P. Mcdonnell

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We have previously identified a family of novel androgen receptor (AR) ligands that, upon binding, enable AR to adopt structures distinct from that observed in the presence of canonical agonists. In this report, we describe the use of these compounds to establish a relationship between AR structure and biological activity with a view to defining a rational approach with which to identify useful selective AR modulators. To this end, we used combinatorial peptide phage display coupled with molecular dynamic structure analysis to identify the surfaces on AR that are exposed specifically in the presence of selected AR ligands. Subsequently, we …

Monoclonal Antibodies To Distinct Regions Of Human Myelin Proteolipid Protein Simultaneously Recognize Central Nervous System Myelin And Neurons Of Many Vertebrate Species, Edward A. Greenfield, Jay Reddy, Andrew Lees, Charissa A. Dyer, Omanand Koul, Khuong Nguyen, Shannon Bell, Nasim Kassam, Julian Hinojoza, Mary Jane Eaton, Marjorie B. Lees, Vijay K. Kuchroo, Raymond A. Sobel

Jay Reddy Publications

Myelin proteolipid protein (PLP), the major protein of mammalian CNS myelin, is a member of the proteolipid gene family (pgf). It is an evolutionarily conserved polytopic integral membrane protein and a potential autoantigen in multiple sclerosis (MS). To analyze antibody recognition of PLP epitopes in situ, monoclonal antibodies (mAbs) specific for different regions of human PLP (50–69, 100–123, 139–151, 178–191, 200–219, 264–276) were generated and used to immunostain CNS tissues of representative vertebrates. mAbs to each region recognized whole human PLP on Western blots; the anti-100–123 mAb did not recognize DM-20, the PLP isoform that lacks residues 116–150. All of …

Or.107. Tim-1 Plays A Crucial Role In The Expansion Of Autopathogneic T-Cells And Regulation Of Autoimmunity [Abstract Only], Sheng Xioa, Nader Najafian, Jay Reddy, Monica Albin, Chen Zhu, Ana Anderson, Zheng Zhang, Cristina Gutierrez, Raymond Sobel, Dale Umetsu, Hideo Yagita, Hisaya Akiba, Mohamed Sayegh, Rosemarie Dekruyff, Vijay K. Kuchroo

Jay Reddy Publications

T-cell immunoglobulin and mucin (TIM) family Members are differentially expressed on Th1 and Th2 cells. Polymorphisms of TIM-1 have been associated with susceptibility to asthma; however, its role in regulating autoimmunity has not been studied. Here, we have used an agonistic antiTIM-1 antibody (Ab, Clone 3B3) which has previously been shown to costimulate T-cell activation and expansion, to analyze the role of TIM-1 in the development and regulation of experimental autoimmune encephalomyelitis (EAE). Treatment with 3B3 dramatically enhances the severity of EAE as well as the frequency of encephalitogenic CD4+ T-cells and the production of IFN-g and IL-17 by these …

The Human Paf Complex Coordinates Transcription With Events Downstream Of Rna Synthesis., Bing Zhu, Subhrangsu S. Mandal, Anh-Dung Pham, Yong Zheng, Hediye Erdjument-Bromage, Surinder K. Batra, Paul Tempst, Danny Reinberg

Journal Articles: Biochemistry & Molecular Biology

The yeast PAF (yPAF) complex interacts with RNA polymerase II and coordinates the setting of histone marks associated with active transcription. We report the isolation and functional characterization of the human PAF (hPAF) complex. hPAF shares four subunits with yPAF (hCtr9, hPaf1, hLeo1, and hCdc73), but contains a novel higher eukaryotic-specific subunit, hSki8. RNAi against hSki8 or hCtr9 reduces the cellular levels of other hPAF subunits and of mono- and trimethylated H3-Lys 4 and dimethylated H3-Lys 79. The hSki8 subunit is also a component of the human SKI (hSKI) complex. Yeast SKI complex is cytoplasmic and together with Exosome mediates …

The Pericentrion: Identification, Characterization, And Function Of A Novel Cpkc-Dependent Compartment, Kevin P. Becker

MUSC Theses and Dissertations

Members of the protein kinase C (PKC) superfamily transduce a myriad of transmembrane signals initiated by the formation of sn-l ,2-diacylglycerol (DAG). As the primary physiological agonist for C] domain containing PKC isoenzymes, DAG functions to regulate the spatial and temporal parameters of PKC activity. It is now recognized that cellular DAG levels can vary from minutes to hours and even days. These observations have suggested a division of PKC functions that correlate to the duration of the cellular DAG signal. In their classical role, cPKCs respond acutely to the short-lived (1-2 min) DAG generated at the plasma membrane by …

Mitochondrial Dna Mutations, Apoptosis, And The Misfolded Protein Response., Justin L. Mott, Dekui Zhang, Hans Peter Zassenhaus

Journal Articles: Biochemistry & Molecular Biology

Studies of transgenic mice with accelerated accumulation of mtDNA mutations specifically in the heart lead us to propose that apoptotic signaling and cell death is central to the pathogenesis of mtDNA mutations in aging. It is the cellular response to that apoptotic signaling and the organ?s compensatory response to a loss of cells that specify the phenotype of an accumulation of mtDNA mutations. In the heart, cardiomyocytes induce a vigorous anti-apoptotic, pro-survival response to counteract mitochondrial apoptotic signaling. The heart up-regulates contractility of remaining myocytes in order to maintain cardiac output. We hypothesize that mutant mitochondrial proteins originate apoptotic signaling …

An Intramolecular Association Between Two Domains Of The Protein Kinase Fused Is Necessary For Hedgehog Signaling, Manuel Ascano Jr., David J. Robbins

Dartmouth Scholarship

The protein kinase Fused (Fu) is an integral member of the Hedgehog (Hh) signaling pathway. Although genetic studies demonstrate that Fu is required for the regulation of the Hh pathway, the mechanistic role that it plays remains largely unknown. Given our difficulty in developing an in vitro kinase assay for Fu, we reasoned that the catalytic activity of Fu might be highly regulated. Several mechanisms are known to regulate protein kinases, including self-association in either an intra- or an intermolecular fashion. Here, we provide evidence that Hh regulates Fu through intramolecular association between its kinase domain (ΔFu) and its carboxyl-terminal …

Multiple Roles Of Mucins In Pancreatic Cancer, A Lethal And Challenging Malignancy., N. Moniaux, M. Andrianifahanana, R. E. Brand, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

Mucins are members of an expanding family of large multifunctional glycoproteins. Pancreatic mucins have important biological functions, including the protection, lubrication, and moisturisation of the surfaces of epithelial tissues lining ductal structures within the pancreas. Several lines of evidence support the notion that deregulated mucin production is a hallmark of inflammatory and neoplastic disorders of the pancreas. Herein, we discuss the factors that contribute to the lethality of pancreatic cancer as well as the key role played by mucins, particularly MUC1 and MUC4, in the development and progression of the disease. Aspects pertaining to the aberrant expression and glycosylation of …

Modified Amino Acid Copolymers Suppress Myelin Basic Protein 85–99-Induced Encephalomyelitis In Humanized Mice Through Different Effects On T Cells, Zsolt Illés, Joel N.H. Stern, Jay Reddy, Hanspeter Waldner, Marcin P. Mycko, Celia F. Brosnan, Stephan Ellmerich, Daniel M. Altmann, Laura Santambrogio, Jack L. Strominger, Vijay K. Kuchroo

Jay Reddy Publications

A humanized mouse bearing the HLA-DR2 (DRA/DRB1*1501) pro- tein associated with multiple sclerosis (MS) and the myelin basic protein (MBP) 85–99-specific HLA-DR2-restricted T cell receptor from an MS patient has been used to examine the effectiveness of modified amino acid copolymers poly(F,Y,A,K)n and poly- (V,W,A,K)n in therapy of MBP 85–99-induced experimental auto-immune encephalomyelitis (EAE) in comparison to Copolymer 1 [Copaxone, poly(Y,E,A,K)n]. The copolymers were designed to optimize binding to HLA-DR2. Vaccination, prevention, and treatment of MBP-induced EAE in the humanized mice with copolymers FYAK and VWAK ameliorated EAE more effectively than Copolymer 1, reduced the number of pathological lesions, and …

Transcriptional Activation Of The Human Prostatic Acid Phosphatase Gene By Nf-Kappab Via A Novel Hexanucleotide-Binding Site., Stanislav Zelivianski, Richard Glowacki, Ming-Fong Lin

Journal Articles: Biochemistry & Molecular Biology

Human prostatic acid phosphatase (PAcP) is a prostate epithelium-specific differentiation antigen. Cellular PAcP functions as a neutral protein tyrosine phosphatase and is involved in regulating androgen-promoted prostate cancer cell proliferation. Despite the fact that the promoter of the PAcP gene has been cloned, the transcriptional factors that regulate PAcP expression remain unidentified. This article describes our analyses of the promoter of the PAcP gene. Deletion analyses of the promoter sequence up to -4893 (-4893/+87) revealed that a 577 bp fragment (-1356/-779) represents the unique positive cis-active element in human prostate cancer cells but not in HeLa cervix carcinoma cells. Interestingly, …

Muc4 Mucin Expression In Human Pancreatic Tumours Is Affected By Organ Environment: The Possible Role Of Tgfbeta2., A. Choudhury, N. Moniaux, A. B. Ulrich, B. M. Schmied, J. Standop, Parviz M. Pour, S. J. Gendler, Michael A. Hollingsworth, J-P Aubert, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

MUC4 is highly expressed in human pancreatic tumours and pancreatic tumour cell lines, but is minimally or not expressed in normal pancreas or chronic pancreatitis. Here, we investigated the aberrant regulation of MUC4 expression in vivo using clonal human pancreatic tumour cells (CD18/HPAF) grown either orthotopically in the pancreas (OT) or ectopically in subcutaneous tissue (SC) in the nude mice. Histological examination of the OT and SC tumours showed moderately differentiated and anaplastic morphology, respectively. The OT tumour cells showed metastases to distant lymph nodes and faster tumour growth (P

The Nuclear Pore Complex And The Dead Box Protein Rat8p/Dbp5p Have Nonessential Features Which Appear To Facilitate Mrna Export Following Heat Shock, Christiane Rollenhagen, Christine A. Hodge, Charles N. Cole

Dartmouth Scholarship

Nuclear pore complexes (NPCs) play an essential role in RNA export. Nucleoporins required for mRNA export in Saccharomyces cerevisiae are found in the Nup84p and Nup82p subcomplexes of the NPC. The Nup82p subcomplex contains Nup82p, Rat7p/Nup159p, Nsp1p, Gle1p/Rss1p, and Rip1p/Nup42p and is found only on the cytoplasmic face of NPCs. Both Rat7p and Gle1p contain binding sites for Rat8p/Dbp5p, an essential DEAD box protein and putative RNA helicase. Rip1p interacts directly with Gle1p and is the only protein known to be essential for mRNA export after heat shock but not under normal growth conditions. We report that in cells lacking …

Amelioration Of Proteolipid Protein 139–151-Induced Encephalomyelitis In Sjl Mice By Modified Amino Acid Copolymers And Their Mechanisms, Joel N.H. Stern, Zsolt Illés, Jay Reddy, Derin B. Keskin, Eric Sheu, Masha Fridkis-Hareli, Hiroyuki Nishimura, Celia F. Brosnan, Laura Santambrogio, Vijay K. Kuchroo, Jack L. Strominger

Jay Reddy Publications

Copolymer 1 [Cop1, glatiramer acetate, Copaxone, poly(Y,E,A,K)n] is widely used in the treatment of relapsing/remitting multiple sclerosis in which it reduces the frequency of relapses by ≈30%. In the present study, copolymers with modified amino acid compositions (based on the binding motif of myelin basic protein 85–99 to HLA-DR2) have been developed with the aim of suppressing multiple sclerosis more effectively. The enhanced efficacy of these copolymers in experimental autoimmune encephalomyelitis (EAE) induced in SJL/J mice with proteolipid protein 139–151 was demonstrated by using three protocols: (i) simultaneous administration of autoantigen and copolymer (termed prevention), (ii) …

Nucleotide Excision Repair- And Polymerase Eta-Mediated Error-Prone Removal Of Mitomycin C Interstrand Cross-Links, H. Zheng, X. Wang, A. J. Warren, R. J. Legerski, Rodney S. Nairn, Joshua W. Hamilton, Lei Li

Dartmouth Scholarship

Interstrand cross-links (ICLs) make up a unique class of DNA lesions in which both strands of the double helix are covalently joined, precluding strand opening during replication and transcription. The repair of DNA ICLs has become a focus of study since ICLs are recognized as the main cytotoxic lesion inflicted by an array of alkylating compounds used in cancer treatment. As is the case for double-strand breaks, a damage-free homologous copy is essential for the removal of ICLs in an error-free manner. However, recombination-independent mechanisms may exist to remove ICLs in an error-prone fashion. We have developed an in vivo …