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Principles For Enhancing Virus Capsid Capacity And Stability From A Thermophilic Virus Capsid Structure, Nicholas P. Stone, Gabriel Demo, Emily Agnello, Brian A. Kelch 2019 University of Massachusetts Medical School

Principles For Enhancing Virus Capsid Capacity And Stability From A Thermophilic Virus Capsid Structure, Nicholas P. Stone, Gabriel Demo, Emily Agnello, Brian A. Kelch

University of Massachusetts Medical School Faculty Publications

The capsids of double-stranded DNA viruses protect the viral genome from the harsh extracellular environment, while maintaining stability against the high internal pressure of packaged DNA. To elucidate how capsids maintain stability in an extreme environment, we used cryoelectron microscopy to determine the capsid structure of the thermostable phage P74-26. We find the P74-26 capsid exhibits an overall architecture that is very similar to those of other tailed bacteriophages, allowing us to directly compare structures to derive the structural basis for enhanced stability. Our structure reveals lasso-like interactions that appear to function like catch bonds. This architecture allows the capsid ...


Debrowser: Interactive Differential Expression Analysis And Visualization Tool For Count Data, Alper Kucukural, Onur Yukselen, Deniz M. Ozata, Melissa J. Moore, Manuel Garber 2019 University of Massachusetts Medical School

Debrowser: Interactive Differential Expression Analysis And Visualization Tool For Count Data, Alper Kucukural, Onur Yukselen, Deniz M. Ozata, Melissa J. Moore, Manuel Garber

Program in Bioinformatics and Integrative Biology Publications and Presentations

BACKGROUND: Sequencing data has become a standard measure of diverse cellular activities. For example, gene expression is accurately measured by RNA sequencing (RNA-Seq) libraries, protein-DNA interactions are captured by chromatin immunoprecipitation sequencing (ChIP-Seq), protein-RNA interactions by crosslinking immunoprecipitation sequencing (CLIP-Seq) or RNA immunoprecipitation (RIP-Seq) sequencing, DNA accessibility by assay for transposase-accessible chromatin (ATAC-Seq), DNase or MNase sequencing libraries. The processing of these sequencing techniques involves library-specific approaches. However, in all cases, once the sequencing libraries are processed, the result is a count table specifying the estimated number of reads originating from each genomic locus. Differential analysis to determine which loci ...


The Trim-Nhl Protein Nhl-2 Is A Co-Factor In The Nuclear And Somatic Rnai Pathways In C. Elegans, Gregory M. Davis, Shikui Tu, Jacqueline A. Wilce, Julie M. Claycomb, Zhiping Weng, Peter R. Boag 2018 Federation University

The Trim-Nhl Protein Nhl-2 Is A Co-Factor In The Nuclear And Somatic Rnai Pathways In C. Elegans, Gregory M. Davis, Shikui Tu, Jacqueline A. Wilce, Julie M. Claycomb, Zhiping Weng, Peter R. Boag

Program in Bioinformatics and Integrative Biology Publications and Presentations

Proper regulation of germline gene expression is essential for fertility and maintaining species integrity. In the C. elegans germline, a diverse repertoire of regulatory pathways promote the expression of endogenous germline genes and limit the expression of deleterious transcripts to maintain genome homeostasis. Here we show that the conserved TRIM-NHL protein, NHL-2, plays an essential role in the C. elegans germline, modulating germline chromatin and meiotic chromosome organization. We uncover a role for NHL-2 as a co-factor in both positively (CSR-1) and negatively (HRDE-1) acting germline 22G-small RNA pathways and the somatic nuclear RNAi pathway. Furthermore, we demonstrate that NHL-2 ...


Hla-Do Modulates The Diversity Of The Mhc-Ii Self-Peptidome, Padma P. Nanaware, Mollie M. Jurewicz, John D. Leszyk, Scott A. Shaffer, Lawrence J. Stern 2018 University of Massachusetts Medical School

Hla-Do Modulates The Diversity Of The Mhc-Ii Self-Peptidome, Padma P. Nanaware, Mollie M. Jurewicz, John D. Leszyk, Scott A. Shaffer, Lawrence J. Stern

Open Access Articles

Presentation of antigenic peptides on MHC-II molecules is essential for tolerance to self and for initiation of immune responses against foreign antigens. DO (HLA-DO in humans, H2-O in mice) is a non-classical MHC-II protein that has been implicated in control of autoimmunity and regulation of neutralizing antibody responses to viruses. These effects likely are related to a role of DO in selecting MHC-II epitopes, but previous studies examining the effect of DO on presentation of selected CD4 T cell epitopes have been contradictory. To understand how DO modulates MHC-II antigen presentation, we characterized the full spectrum of peptides presented by ...


Protective Versus Pathologic Pre-Exposure Cytokine Profiles In Dengue Virus Infection, Heather Friberg, Coreen M. Beaumier, Sangshin Park, Pamela P. Pazoles, Timothy P. Endy, Anuja Mathew, Jeffrey R. Currier, Richard G. Jarman, Kathryn B. Anderson, Steven Hatch, Stephen J. Thomas, Alan L. Rothman 2018 Walter Reed Army Institute of Research

Protective Versus Pathologic Pre-Exposure Cytokine Profiles In Dengue Virus Infection, Heather Friberg, Coreen M. Beaumier, Sangshin Park, Pamela P. Pazoles, Timothy P. Endy, Anuja Mathew, Jeffrey R. Currier, Richard G. Jarman, Kathryn B. Anderson, Steven Hatch, Stephen J. Thomas, Alan L. Rothman

Open Access Articles

BACKGROUND: Hyperendemic circulation of all four types of dengue virus (DENV-1-4) has expanded globally, fueling concern for increased incidence of severe dengue. While the majority of DENV infections are subclinical, epidemiologic studies suggest that type-cross-reactive immunity can influence disease outcome in subsequent infections. The mechanisms controlling these differential clinical outcomes remain poorly defined.

METHODOLOGY/PRINCIPAL FINDINGS: Blood samples were collected from a cohort of school-aged Thai children who subsequently experienced a subclinical DENV infection or developed dengue illness. PBMC collected prior to infection were stimulated in vitro with DENV and the secretion of 30 cytokines was measured using a multiplexed ...


Cpla2alpha-/- Sympathetic Neurons Exhibit Increased Membrane Excitability And Loss Of N-Type Ca2+ Current Inhibition By M1 Muscarinic Receptor Signaling, Liwang Liu, Joseph V. Bonventre, Ann R. Rittenhouse 2018 University of Massachusetts Medical School

Cpla2alpha-/- Sympathetic Neurons Exhibit Increased Membrane Excitability And Loss Of N-Type Ca2+ Current Inhibition By M1 Muscarinic Receptor Signaling, Liwang Liu, Joseph V. Bonventre, Ann R. Rittenhouse

Open Access Articles

Group IVa cytosolic phospholipase A2 (cPLA2alpha) mediates GPCR-stimulated arachidonic acid (AA) release from phosphatidylinositol 4,5-bisphosphate (PIP2) located in plasma membranes. We previously found in superior cervical ganglion (SCG) neurons that PLA2 activity is required for voltage-independent N-type Ca2+ (N-) current inhibition by M1 muscarinic receptors (M1Rs). These findings are at odds with an alternative model, previously observed for M-current inhibition, where PIP2 dissociation from channels and subsequent metabolism by phospholipase C suffices for current inhibition. To resolve cPLA2alpha's importance, we have investigated its role in mediating voltage-independent N-current inhibition (~40%) that follows application of the muscarinic agonist oxotremorine-M ...


Resistance From Afar: Distal Mutation V36m Allosterically Modulates The Active Site To Accentuate Drug Resistance In Hcv Ns3/4a Protease, Aysegul Ozen, Kuan-Hung Lin, Keith P. Romano, Davide Tavella, Alicia Newton, Christos J. Petropoulos, Wei Huang, Cihan Aydin, Celia A. Schiffer 2018 University of Massachusetts Medical School

Resistance From Afar: Distal Mutation V36m Allosterically Modulates The Active Site To Accentuate Drug Resistance In Hcv Ns3/4a Protease, Aysegul Ozen, Kuan-Hung Lin, Keith P. Romano, Davide Tavella, Alicia Newton, Christos J. Petropoulos, Wei Huang, Cihan Aydin, Celia A. Schiffer

University of Massachusetts Medical School Faculty Publications

Hepatitis C virus rapidly evolves, conferring resistance to direct acting antivirals. While resistance via active site mutations in the viral NS3/4A protease has been well characterized, the mechanism for resistance of non-active site mutations is unclear. R155K and V36M often co-evolve and while R155K alters the electrostatic network at the binding site, V36M is more than 13 Angstrom away. In this study the mechanism by which V36M confers resistance, in the context of R155K, is elucidated with drug susceptibility assays, crystal structures, and molecular dynamics (MD) simulations for three protease inhibitors: telaprevir, boceprevir and danoprevir. The R155K and R155K ...


Intron-Containing Rna From The Hiv-1 Provirus Activates Type I Interferon And Inflammatory Cytokines, Sean M. McCauley, Kyusik Kim, Anetta Nowosielska, Ann Dauphin, Leonid Yurkovetskiy, William E. Diehl, Jeremy Luban 2018 University of Massachusetts Medical School

Intron-Containing Rna From The Hiv-1 Provirus Activates Type I Interferon And Inflammatory Cytokines, Sean M. Mccauley, Kyusik Kim, Anetta Nowosielska, Ann Dauphin, Leonid Yurkovetskiy, William E. Diehl, Jeremy Luban

Open Access Articles

HIV-1-infected people who take drugs that suppress viremia to undetectable levels are protected from developing AIDS. Nonetheless, HIV-1 establishes proviruses in long-lived CD4(+) memory T cells, and perhaps other cell types, that preclude elimination of the virus even after years of continuous antiviral therapy. Here we show that the HIV-1 provirus activates innate immune signaling in isolated dendritic cells, macrophages, and CD4(+) T cells. Immune activation requires transcription from the HIV-1 provirus and expression of CRM1-dependent, Rev-dependent, RRE-containing, unspliced HIV-1 RNA. If rev is provided in trans, all HIV-1 coding sequences are dispensable for activation except those cis-acting sequences required ...


Manganese Influx And Expression Of Zip8 Is Essential In Primary Myoblasts And Contributes To Activation Of Sod2, Shellaina J. V. Gordon, Daniel E. Fenker, Katherine E. Vest, Teresita Padilla-Benavides 2018 University of Massachusetts Medical School

Manganese Influx And Expression Of Zip8 Is Essential In Primary Myoblasts And Contributes To Activation Of Sod2, Shellaina J. V. Gordon, Daniel E. Fenker, Katherine E. Vest, Teresita Padilla-Benavides

University of Massachusetts Medical School Faculty Publications

Trace elements such as copper (Cu), zinc (Zn), iron (Fe), and manganese (Mn) are enzyme cofactors and second messengers in cell signaling. Trace elements are emerging as key regulators of differentiation and development of mammalian tissues including blood, brain, and skeletal muscle. We previously reported an influx of Cu and dynamic expression of various metal transporters during differentiation of skeletal muscle cells. Here, we demonstrate that during differentiation of skeletal myoblasts an increase of additional trace elements such as Mn, Fe and Zn occurs. Interestingly the Mn increase is concomitant with increased Mn-dependent SOD2 levels. To better understand the Mn ...


The Caenorhabditis Elegans Oxidative Stress Response Requires The Nhr-49 Transcription Factor, Queenie Hu, Dayana R. D'Amora, Lesley T. MacNeil, Albertha J. M. Walhout, Terrance J. Kubiseski 2018 York University

The Caenorhabditis Elegans Oxidative Stress Response Requires The Nhr-49 Transcription Factor, Queenie Hu, Dayana R. D'Amora, Lesley T. Macneil, Albertha J. M. Walhout, Terrance J. Kubiseski

Open Access Articles

The overproduction of reactive oxygen species (ROS) in cells can lead to the development of diseases associated with aging. We have previously shown that C. elegans BRAP-2 (Brca1 associated binding protein 2) regulates phase II detoxification genes such as gst-4, by increasing SKN-1 activity. Previously, a transcription factor (TF) RNAi screen was conducted to identify potential activators that are required to induce gst-4 expression in brap-2(ok1492) mutants. The lipid metabolism regulator NHR-49/HNF4 was among 18 TFs identified. Here, we show that knockdown of nhr-49 suppresses the activation of gst-4 caused by brap-2 inactivation and that gain-of-function alleles of ...


Conserved Mrna-Granule Component Scd6 Targets Dhh1 To Repress Translation Initiation And Activates Dcp2-Mediated Mrna Decay In Vivo, Quira Zeidan, Feng He, Fan Zhang, Hongen Zhang, Allan Jacobson, Alan G. Hinnebusch 2018 Eunice Kennedy Shriver National Institute of Child Health and Development

Conserved Mrna-Granule Component Scd6 Targets Dhh1 To Repress Translation Initiation And Activates Dcp2-Mediated Mrna Decay In Vivo, Quira Zeidan, Feng He, Fan Zhang, Hongen Zhang, Allan Jacobson, Alan G. Hinnebusch

Open Access Articles

Scd6 protein family members are evolutionarily conserved components of translationally silent mRNA granules. Yeast Scd6 interacts with Dcp2 and Dhh1, respectively a subunit and a regulator of the mRNA decapping enzyme, and also associates with translation initiation factor eIF4G to inhibit translation in cell extracts. However, the role of Scd6 in mRNA turnover and translational repression in vivo is unclear. We demonstrate that tethering Scd6 to a GFP reporter mRNA reduces mRNA abundance via Dcp2 and suppresses reporter mRNA translation via Dhh1. Thus, in a dcp2Delta mutant, tethered Scd6 reduces GFP protein expression with little effect on mRNA abundance, whereas ...


Peptidylarginine Deiminases 2 And 4 Modulate Innate And Adaptive Immune Responses In Tlr-7-Dependent Lupus., Yudong Liu, Yaíma L Lightfoot, Nickie Seto, Santanu Mondal, Padmavathy Nandha Premnath, Paul R. Thompson 2018 National Institute of Arthritis and Musculoskeletal and Skin Diseases

Peptidylarginine Deiminases 2 And 4 Modulate Innate And Adaptive Immune Responses In Tlr-7-Dependent Lupus., Yudong Liu, Yaíma L Lightfoot, Nickie Seto, Santanu Mondal, Padmavathy Nandha Premnath, Paul R. Thompson

University of Massachusetts Medical School Publications

The peptidylarginine deiminases PAD2 and PAD4 are implicated in the pathogenesis of several autoimmune diseases. PAD4 may be pathogenic in systemic lupus erythematosus (SLE) through its role in neutrophil extracellular trap (NET) formation that promotes autoantigen externalization, immune dysregulation, and organ damage. The role of this enzyme in mouse models of autoimmunity remains unclear, as pan-PAD chemical inhibitors improve clinical phenotype, whereas PAD4-KO models have given conflicting results. The role of PAD2 in SLE has not been investigated. The differential roles of PAD2 and PAD4 in TLR-7-dependent lupus autoimmunity were examined. Padi4-/- displayed decreased autoantibodies, type I IFN responses, immune ...


Establishing Trust In Hiv/Hcv Research Among People Who Inject Drugs (Pwid): Insights From Empirical Research, Roberto Abadie, Shira Goldenberg, Melissa Welch-Lazoritz, Celia B. Fisher 2018 University of Nebraska-Lincoln

Establishing Trust In Hiv/Hcv Research Among People Who Inject Drugs (Pwid): Insights From Empirical Research, Roberto Abadie, Shira Goldenberg, Melissa Welch-Lazoritz, Celia B. Fisher

Sociology Department, Faculty Publications

Background — The establishment of trust between researchers and participants is critical to advance HIV and HCV prevention particularly among people who inject drugs (PWID) and other marginalized populations, yet empirical research on how to establish and maintain trust in the course of community health research is lacking. This paper documents ideas about trust between research participants and researchers amongst a sub-sample of PWID who were enrolled in a large, multi-year community health study of social networks and HIV/HCV risk that was recently conducted in rural Puerto Rico.

Methods — Qualitative research was nested within a multi-year Social Network and HIV ...


Two Contrasting Classes Of Nucleolus-Associated Domains In Mouse Fibroblast Heterochromatin, Anastassiia Vertii, Jianhong Ou, Jun Yu, Aimin Yan, Hervé Pagès, Haibo Liu, Lihua Julie Zhu, Paul D. Kaufman 2018 University of Massachusetts Medical School

Two Contrasting Classes Of Nucleolus-Associated Domains In Mouse Fibroblast Heterochromatin, Anastassiia Vertii, Jianhong Ou, Jun Yu, Aimin Yan, Hervé Pagès, Haibo Liu, Lihua Julie Zhu, Paul D. Kaufman

University of Massachusetts Medical School Faculty Publications

In interphase eukaryotic cells, almost all heterochromatin is located adjacent to the nucleolus or to the nuclear lamina, thus defining Nucleolus Associated Domains (NADs) and Lamina Associated Domains (LADs), respectively. Here, we determined the first genome-scale map of murine NADs in mouse embryonic fibroblasts (MEFs) via deep sequencing of chromatin associated with purified nucleoli. We developed a Bioconductor package called NADfinder and demonstrated that it identifies NADs more accurately than other peak-calling tools, due to its critical feature of chromosome-level local baseline correction. We detected two distinct classes of NADs. Type I NADs associate frequently with both the nucleolar periphery ...


Removal Of Carbamazepine From Drinking Water, Thomas Krumpolc, Juan Rodriguez, Jordan Alex Gadberry, Zach Wiese, Paola Marrero-Rivera, Adam Johnson 2018 University of Arkansas, Fayetteville

Removal Of Carbamazepine From Drinking Water, Thomas Krumpolc, Juan Rodriguez, Jordan Alex Gadberry, Zach Wiese, Paola Marrero-Rivera, Adam Johnson

Chemical Engineering Undergraduate Honors Theses

Due to the increasing prevalence of prescription medication over the past few decades, pharmaceuticals have accumulated in various water sources. This has become a public health concern because many pharmaceuticals have limited research on the effects of chronic low-level exposure. According to the World’s Health Organization (WHO), traces of pharmaceuticals products have been reported in different water sources such as surface waters, wastewater, groundwater, and drinking water.[1] One pharmaceutical of interest that has been detected in water sources is carbamazepine. Carbamazepine (CBZ) is a common pharmaceutical prescribed for the treatment of seizure disorders, neuropathic pain, and various psychological ...


The Study Of Alcoholic Liver Diseases, Seun Emmanuel Owoseni 2018 East Tennessee State University

The Study Of Alcoholic Liver Diseases, Seun Emmanuel Owoseni

Electronic Theses and Dissertations

Excessive alcohol consumption is the primary contributing factor in the development of alcoholic liver diseases (ALD). Nicotine contained in tobacco is a major addictive alkaloid, which enhances the effects of ALDs. The major enzyme involved in nicotine metabolism is cytochrome P450 2A5 (CYP2A5) which is produced in the liver. Alcohol can stimulate the CYP2A5 enzyme. We utilized cyp2a5-/- knockout mice in this research to examine the effects of CYP2A5.

The cyp2a5-/- mice and wild-type (WT) mice were fed liquid ethanol diet with or without nicotine to induce ALD. Nicotine enhancing effects on ALD were observed in WT mice but not ...


Stress-Responsive And Metabolic Gene Regulation Are Altered In Low S-Adenosylmethionine, Wei Ding, Daniel P. Higgins, Dilip K. Yadav, Adwait A. Godbole, Read Pukkila-Worley, Amy K. Walker 2018 University of Massachusetts Medical School

Stress-Responsive And Metabolic Gene Regulation Are Altered In Low S-Adenosylmethionine, Wei Ding, Daniel P. Higgins, Dilip K. Yadav, Adwait A. Godbole, Read Pukkila-Worley, Amy K. Walker

Open Access Articles

S-adenosylmethionine (SAM) is a donor which provides the methyl groups for histone or nucleic acid modification and phosphatidylcholine production. SAM is hypothesized to link metabolism and chromatin modification, however, its role in acute gene regulation is poorly understood. We recently found that Caenorhabditis elegans with reduced SAM had deficiencies in H3K4 trimethylation (H3K4me3) at pathogen-response genes, decreasing their expression and limiting pathogen resistance. We hypothesized that SAM may be generally required for stress-responsive transcription. Here, using genetic assays, we show that transcriptional responses to bacterial or xenotoxic stress fail in C. elegans with low SAM, but that expression of heat ...


Genome-Wide Crispr Screens For Shiga Toxins And Ricin Reveal Golgi Proteins Critical For Glycosylation, Songhai Tian, Khaja Muneeruddin, Mei Yuk Choi, Liang Tao, Robiul H. Bhuiyan, Yuhsuke Ohmi, Keiko Furukawa, Koichi Furukawa, Sebastian Boland, Scott A. Shaffer, Rosalyn M. Adam, Min Dong 2018 Harvard Medical School

Genome-Wide Crispr Screens For Shiga Toxins And Ricin Reveal Golgi Proteins Critical For Glycosylation, Songhai Tian, Khaja Muneeruddin, Mei Yuk Choi, Liang Tao, Robiul H. Bhuiyan, Yuhsuke Ohmi, Keiko Furukawa, Koichi Furukawa, Sebastian Boland, Scott A. Shaffer, Rosalyn M. Adam, Min Dong

Open Access Articles

Glycosylation is a fundamental modification of proteins and membrane lipids. Toxins that utilize glycans as their receptors have served as powerful tools to identify key players in glycosylation processes. Here, we carried out Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-Cas9-mediated genome-wide loss-of-function screens using two related bacterial toxins, Shiga-like toxins (Stxs) 1 and 2, which use a specific glycolipid, globotriaosylceramide (Gb3), as receptors, and the plant toxin ricin, which recognizes a broad range of glycans. The Stxs screens identified major glycosyltransferases (GTs) and transporters involved in Gb3 biosynthesis, while the ricin screen identified GTs and transporters involved in N-linked ...


Cryptococcus Neoformans Cda1 And Its Chitin Deacetylase Activity Are Required For Fungal Pathogenesis, Rajendra Upadhya, Lorina G. Baker, Woei C. Lam, Charles A. Specht, Maureen J. Donlin, Jennifer K. Lodge 2018 Washington University

Cryptococcus Neoformans Cda1 And Its Chitin Deacetylase Activity Are Required For Fungal Pathogenesis, Rajendra Upadhya, Lorina G. Baker, Woei C. Lam, Charles A. Specht, Maureen J. Donlin, Jennifer K. Lodge

Open Access Articles

Chitin is an essential component of the cell wall of Cryptococcus neoformans conferring structural rigidity and integrity under diverse environmental conditions. Chitin deacetylase genes encode the enyzmes (chitin deacetylases [Cdas]) that deacetylate chitin, converting it to chitosan. The functional role of chitosan in the fungal cell wall is not well defined, but it is an important virulence determinant of C. neoformans Mutant strains deficient in chitosan are completely avirulent in a mouse pulmonary infection model. C. neoformans carries genes that encode three Cdas (Cda1, Cda2, and Cda3) that appear to be functionally redundant in cells grown under vegetative conditions. Here ...


Orthogonal Cas9-Cas9 Chimeras Provide A Versatile Platform For Genome Editing, Mehmet F. Bolukbasi, Pengpeng Liu, Kevin Luk, Samantha F. Kwok, Ankit Gupta, Nadia Amrani, Erik J. Sontheimer, Lihua Julie Zhu, Scot A. Wolfe 2018 University of Massachusetts Medical School

Orthogonal Cas9-Cas9 Chimeras Provide A Versatile Platform For Genome Editing, Mehmet F. Bolukbasi, Pengpeng Liu, Kevin Luk, Samantha F. Kwok, Ankit Gupta, Nadia Amrani, Erik J. Sontheimer, Lihua Julie Zhu, Scot A. Wolfe

Open Access Articles

The development of robust, versatile and accurate toolsets is critical to facilitate therapeutic genome editing applications. Here we establish RNA-programmable Cas9-Cas9 chimeras, in single- and dual-nuclease formats, as versatile genome engineering systems. In both of these formats, Cas9-Cas9 fusions display an expanded targeting repertoire and achieve highly specific genome editing. Dual-nuclease Cas9-Cas9 chimeras have distinct advantages over monomeric Cas9s including higher target site activity and the generation of predictable precise deletion products between their target sites. At a therapeutically relevant site within the BCL11A erythroid enhancer, Cas9-Cas9 nucleases produced precise deletions that comprised up to 97% of all sequence alterations ...


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