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Articles 1 - 30 of 1453

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Molecular And Structural Mechanism Of Pan-Genotypic Hcv Ns3/4a Protease Inhibition By Glecaprevir, Jennifer Timm, Klajdi Kosovrasti, Mina Henes, Florian Leidner, Shurong Hou, Akbar Ali, Nese Kurt Yilmaz, Celia A. Schiffer Jul 2019

Molecular And Structural Mechanism Of Pan-Genotypic Hcv Ns3/4a Protease Inhibition By Glecaprevir, Jennifer Timm, Klajdi Kosovrasti, Mina Henes, Florian Leidner, Shurong Hou, Akbar Ali, Nese Kurt Yilmaz, Celia A. Schiffer

University of Massachusetts Medical School Faculty Publications

Hepatitis C virus (HCV), causative agent of chronic viral hepatitis, infects 71 million people worldwide and is divided into seven genotypes and multiple subtypes with sequence identities between 68 to 82%. While older generation direct-acting antivirals (DAAs) had varying effectiveness against different genotypes, the newest NS3/4A protease inhibitors including glecaprevir (GLE) have pan-genotypic activity. The structural basis for pan-genotypic inhibition and effects of polymorphisms on inhibitor potency were not well known due to lack of crystal structures of GLE-bound NS3/4A or genotypes other than 1. In this study, we determined the crystal structures of NS3/4A from genotypes ...


A Chromosome Folding Intermediate At The Condensin-To-Cohesin Transition During Telophase, Kristin Abramo, Anne-Laure Valton, Sergey V. Venev, Hakan Ozadam, A. Nicole Fox, Job Dekker Jun 2019

A Chromosome Folding Intermediate At The Condensin-To-Cohesin Transition During Telophase, Kristin Abramo, Anne-Laure Valton, Sergey V. Venev, Hakan Ozadam, A. Nicole Fox, Job Dekker

University of Massachusetts Medical School Faculty Publications

Chromosome folding is extensively modulated as cells progress through the cell cycle. During mitosis, condensin complexes fold chromosomes in helically arranged nested loop arrays. In interphase, the cohesin complex generates loops that can be stalled at CTCF sites leading to positioned loops and topologically associating domains (TADs), while a separate process of compartmentalization drives the spatial segregation of active and inactive chromatin domains. We used synchronized cell cultures to determine how the mitotic chromosome conformation is transformed into the interphase state. Using Hi-C, chromatin binding assays, and immunofluorescence we show that by telophase condensin-mediated loops are lost and a transient ...


In Situ Structure Of Rotavirus Vp1 Rna-Dependent Rna Polymerase, Simon Jenni, Eric N. Salgado, Tobias Herrmann, Zongli Li, Timothy Grant, Nikolaus Grigorieff, Stefano Trapani, Leandro F. Estrozi, Stephen C. Harrison Jun 2019

In Situ Structure Of Rotavirus Vp1 Rna-Dependent Rna Polymerase, Simon Jenni, Eric N. Salgado, Tobias Herrmann, Zongli Li, Timothy Grant, Nikolaus Grigorieff, Stefano Trapani, Leandro F. Estrozi, Stephen C. Harrison

Open Access Articles

Rotaviruses, like other non-enveloped, double-strand RNA viruses, package an RNA-dependent RNA polymerase (RdRp) with each duplex of their segmented genomes. Rotavirus cell entry results in loss of an outer protein layer and delivery into the cytosol of an intact, inner capsid particle (the "double-layer particle," or DLP). The RdRp, designated VP1, is active inside the DLP; each VP1 achieves many rounds of mRNA transcription from its associated genome segment. Previous work has shown that one VP1 molecule lies close to each 5-fold axis of the icosahedrally symmetric DLP, just beneath the inner surface of its protein shell, embedded in tightly ...


Extracellular-Signal Regulated Kinase: A Central Molecule Driving Epithelial-Mesenchymal Transition In Cancer, Monserrat Olea-Flores, Miriam Daniela Zuniga-Eulogio, Miguel Angel Mendoza-Catalan, Hugo Alberto Rodriguez-Ruiz, Eduardo Castaneda-Saucedo, Carlos Ortuno-Pineda, Teresita Padilla-Benavides, Napoleon Navarro-Tito Jun 2019

Extracellular-Signal Regulated Kinase: A Central Molecule Driving Epithelial-Mesenchymal Transition In Cancer, Monserrat Olea-Flores, Miriam Daniela Zuniga-Eulogio, Miguel Angel Mendoza-Catalan, Hugo Alberto Rodriguez-Ruiz, Eduardo Castaneda-Saucedo, Carlos Ortuno-Pineda, Teresita Padilla-Benavides, Napoleon Navarro-Tito

Open Access Articles

Epithelial-mesenchymal transition (EMT) is a reversible cellular process, characterized by changes in gene expression and activation of proteins, favoring the trans-differentiation of the epithelial phenotype to a mesenchymal phenotype. This process increases cell migration and invasion of tumor cells, progression of the cell cycle, and resistance to apoptosis and chemotherapy, all of which support tumor progression. One of the signaling pathways involved in tumor progression is the MAPK pathway. Within this family, the ERK subfamily of proteins is known for its contributions to EMT. The ERK subfamily is divided into typical (ERK 1/2/5), and atypical (ERK 3/4 ...


Trim5alpha Restricts Flavivirus Replication By Targeting The Viral Protease For Proteasomal Degradation, Abhilash I. Chiramel, Nicholas R. Meyerson, Kristin L. Mcnally, Rebecca M. Broeckel, Vanessa R. Montoya, Omayra Mendez-Solis, Shelly J. Robertson, Gail L. Sturdevant, Kirk J. Lubick, Vinod Nair, Brian H. Youseff, Robin M. Ireland, Catharine M. Bosio, Kyusik Kim, Jeremy Luban, Vanessa M. Hirsch, R. Travis Taylor, Fadila Bouamr, Sara L. Sawyer, Sonja M. Best Jun 2019

Trim5alpha Restricts Flavivirus Replication By Targeting The Viral Protease For Proteasomal Degradation, Abhilash I. Chiramel, Nicholas R. Meyerson, Kristin L. Mcnally, Rebecca M. Broeckel, Vanessa R. Montoya, Omayra Mendez-Solis, Shelly J. Robertson, Gail L. Sturdevant, Kirk J. Lubick, Vinod Nair, Brian H. Youseff, Robin M. Ireland, Catharine M. Bosio, Kyusik Kim, Jeremy Luban, Vanessa M. Hirsch, R. Travis Taylor, Fadila Bouamr, Sara L. Sawyer, Sonja M. Best

Program in Molecular Medicine Publications and Presentations

Tripartite motif-containing protein 5alpha (TRIM5alpha) is a cellular antiviral restriction factor that prevents early events in retrovirus replication. The activity of TRIM5alpha is thought to be limited to retroviruses as a result of highly specific interactions with capsid lattices. In contrast to this current understanding, we show that both human and rhesus macaque TRIM5alpha suppress replication of specific flaviviruses. Multiple viruses in the tick-borne encephalitis complex are sensitive to TRIM5alpha-dependent restriction, but mosquito-borne flaviviruses, including yellow fever, dengue, and Zika viruses, are resistant. TRIM5alpha suppresses replication by binding to the viral protease NS2B/3 to promote its K48-linked ubiquitination and ...


Smooth Muscle Cell-Specific Tmem16a Deletion Does Not Alter Ca2+ Signaling, Uterine Contraction, Gestation Length Or Litter Size In Micedagger, Mingzi Qu, Ping Lu, Karl D. Bellve, Kevin E. Fogarty, Lawrence M. Lifshitz, Fangxiong Shi, Ronghua Zhuge Jun 2019

Smooth Muscle Cell-Specific Tmem16a Deletion Does Not Alter Ca2+ Signaling, Uterine Contraction, Gestation Length Or Litter Size In Micedagger, Mingzi Qu, Ping Lu, Karl D. Bellve, Kevin E. Fogarty, Lawrence M. Lifshitz, Fangxiong Shi, Ronghua Zhuge

Program in Molecular Medicine Publications and Presentations

Ion channels in myometrial cells play critical roles in spontaneous and agonist-induced uterine contraction during the menstrual cycle, pregnancy maintenance and parturition; thus identifying the genes of ion channels in these cells and determining their roles are essential to understanding the biology of reproduction. Previous studies with in vitro functional and pharmacological approaches have produced controversial results regarding the presence and role of TMEM16A Ca2+-activated Cl- channels in myometrial cells. To unambiguously determine the function of this channel in these cells, we employed a genetic approach by using smooth muscle cell-specific TMEM16A deletion (i.e. TMEM16ASMKO) mice. We found ...


Yeast Sirtuin Family Members Maintain Transcription Homeostasis To Ensure Genome Stability, Jessica L. Feldman, Craig L. Peterson Jun 2019

Yeast Sirtuin Family Members Maintain Transcription Homeostasis To Ensure Genome Stability, Jessica L. Feldman, Craig L. Peterson

Program in Molecular Medicine Publications and Presentations

The mammalian sirtuin, SIRT6, is a key tumor suppressor that maintains genome stability and regulates transcription, though how SIRT6 family members control genome stability is unclear. Here, we use multiple genome-wide approaches to demonstrate that the yeast SIRT6 homologs, Hst3 and Hst4, prevent genome instability by tuning levels of both coding and noncoding transcription. While nascent RNAs are elevated in the absence of Hst3 and Hst4, a global impact on steady-state mRNAs is masked by the nuclear exosome, indicating that sirtuins and the exosome provide two levels of regulation to maintain transcription homeostasis. We find that, in the absence of ...


Modulation Of Biological Responses To 2 Ns Electrical Stimuli By Field Reversal, Esin B. Sözer, P. Thomas Vernier Jun 2019

Modulation Of Biological Responses To 2 Ns Electrical Stimuli By Field Reversal, Esin B. Sözer, P. Thomas Vernier

Bioelectrics Publications

Nanosecond bipolar pulse cancellation, a recently discovered Phenomenon, is modulation of the effects of a unipolar electric pulse exposure by a second pulse of opposite polarity. This attenuation of biological response by reversal of the electric field direction has been reported with pulse durations from 60 ns to 900 ns for a wide range of endpoints, and it is not observed with conventional electroporation pulses of much longer duration (> 100 mu s) where pulses are additive regardless of polarity. The most plausible proposed mechanisms involve the field-driven migration of ions to and from the membrane interface (accelerated membrane discharge). Here ...


Nf-Κb In Biomphalaria Glabrata: A Genetic Fluke?, Paige Stocker May 2019

Nf-Κb In Biomphalaria Glabrata: A Genetic Fluke?, Paige Stocker

Lawrence University Honors Projects

Biomphalaria glabrata is the intermediate host to the disease causing parasitic worm, Schistosoma mansoni. Previous work has identified homologs of NF-κB, a known immune related transcription factor, in B. glabrata and work has also been done to establish putative κB sites. It has also been observed that the p65 homologous subunit has an extended N-terminal region not present in other homologs. The goal of the present study is twofold: investigate DNA binding affinity of two NF-κB subunits, Bg-p65 and Bg-p50, and characterize the nature of the N-terminal extension of Bg-p65. In the current work, it is shown through the use ...


An Order-To-Disorder Structural Switch Activates The Foxm1 Transcription Factor, Aimee H. Marceau, Caileen M. Brison, Santrupti Nerli, Heather E. Arsenault, Andrew C. Mcshan, Eefei Chen, Hsiau-Wei Lee, Jennifer A. Benanti, Nikolaos G. Sgourakis, Seth M. Rubin May 2019

An Order-To-Disorder Structural Switch Activates The Foxm1 Transcription Factor, Aimee H. Marceau, Caileen M. Brison, Santrupti Nerli, Heather E. Arsenault, Andrew C. Mcshan, Eefei Chen, Hsiau-Wei Lee, Jennifer A. Benanti, Nikolaos G. Sgourakis, Seth M. Rubin

Open Access Articles

Intrinsically disordered transcription factor transactivation domains (TADs) function through structural plasticity, adopting ordered conformations when bound to transcriptional co-regulators. Many transcription factors contain a negative regulatory domain (NRD) that suppresses recruitment of transcriptional machinery through autoregulation of the TAD. We report the solution structure of an autoinhibited NRD-TAD complex within FoxM1, a critical activator of mitotic gene expression. We observe that while both the FoxM1 NRD and TAD are primarily intrinsically disordered domains, they associate and adopt a structured conformation. We identify how Plk1 and Cdk kinases cooperate to phosphorylate FoxM1, which releases the TAD into a disordered conformation that ...


Serum Deprivation Of Mesenchymal Stem Cells Improves Exosome Activity And Alters Lipid And Protein Composition, Reka A. Haraszti, Rachael Miller, Michelle L. Dubuke, Andrew H. Coles, Marie C. Didiot, Dimas Echeverria, Matteo Stoppato, Yves Y. Sere, John D. Leszyk, Julia F. Alterman, Bruno M. D. C. Godinho, Matthew R. Hassler, Rachel Wollacott, Yan Wang, Scott A. Shaffer, Neil Aronin, Anastasia Khvorova May 2019

Serum Deprivation Of Mesenchymal Stem Cells Improves Exosome Activity And Alters Lipid And Protein Composition, Reka A. Haraszti, Rachael Miller, Michelle L. Dubuke, Andrew H. Coles, Marie C. Didiot, Dimas Echeverria, Matteo Stoppato, Yves Y. Sere, John D. Leszyk, Julia F. Alterman, Bruno M. D. C. Godinho, Matthew R. Hassler, Rachel Wollacott, Yan Wang, Scott A. Shaffer, Neil Aronin, Anastasia Khvorova

Open Access Articles

Exosomes can serve as delivery vehicles for advanced therapeutics. The components necessary and sufficient to support exosomal delivery have not been established. Here we connect biochemical composition and activity of exosomes to optimize exosome-mediated delivery of small interfering RNAs (siRNAs). This information is used to create effective artificial exosomes. We show that serum-deprived mesenchymal stem cells produce exosomes up to 22-fold more effective at delivering siRNAs to neurons than exosomes derived from control cells. Proteinase treatment of exosomes stops siRNA transfer, indicating that surface proteins on exosomes are involved in trafficking. Proteomic and lipidomic analyses show that exosomes derived in ...


Arf Gtpases And Their Gefs And Gaps: Concepts And Challenges, Elizabeth Sztul, Pei-Wen Chen, James E. Casanova, Jacqueline Cherfils, Joel B. Dacks, David G. Lambright, Fang-Jen S. Lee, Paul A. Randazzo, Lorraine C. Santy, Annette Schurmann, Ilka Wilhelmi, Marielle E. Yohe, Richard A. Kahn May 2019

Arf Gtpases And Their Gefs And Gaps: Concepts And Challenges, Elizabeth Sztul, Pei-Wen Chen, James E. Casanova, Jacqueline Cherfils, Joel B. Dacks, David G. Lambright, Fang-Jen S. Lee, Paul A. Randazzo, Lorraine C. Santy, Annette Schurmann, Ilka Wilhelmi, Marielle E. Yohe, Richard A. Kahn

Program in Molecular Medicine Publications and Presentations

Detailed structural, biochemical, cell biological, and genetic studies of any gene/protein are required to develop models of its actions in cells. Studying a protein family in the aggregate yields additional information, as one can include analyses of their coevolution, acquisition or loss of functionalities, structural pliability, and the emergence of shared or variations in molecular mechanisms. An even richer understanding of cell biology can be achieved through evaluating functionally linked protein families. In this review, we summarize current knowledge of three protein families: the ARF GTPases, the guanine nucleotide exchange factors (ARF GEFs) that activate them, and the GTPase-activating ...


Brown Fat Organogenesis And Maintenance Requires Akt1 And Akt2, Joan Sanchez-Gurmaches, Camila Martinez Calejman, Su Myung Jung, Huawei Li, David A. Guertin May 2019

Brown Fat Organogenesis And Maintenance Requires Akt1 And Akt2, Joan Sanchez-Gurmaches, Camila Martinez Calejman, Su Myung Jung, Huawei Li, David A. Guertin

Open Access Articles

OBJECTIVE: Understanding the signaling mechanisms that control brown adipose tissue (BAT) development is relevant to understanding energy homeostasis and obesity. The AKT kinases are insulin effectors with critical in vivo functions in adipocytes; however, their role in adipocyte development remains poorly understood. The goal of this study was to investigate AKT function in BAT development.

METHODS: We conditionally deleted Akt1 and Akt2 either individually or together with Myf5-Cre, which targets early mesenchymal precursors that give rise to brown adipocytes. Because Myf5-Cre also targets skeletal muscle and some white adipocyte lineages, comparisons were made between AKT function in BAT versus white ...


Regulation Of The Drosophila Imd Pathway By Signaling Amyloids, Anni Kleino, Neal S. Silverman May 2019

Regulation Of The Drosophila Imd Pathway By Signaling Amyloids, Anni Kleino, Neal S. Silverman

Open Access Articles

Fruit flies elicit effective defense responses against numerous microbes. The responses against Gram-negative bacteria are mediated by the Imd pathway, an evolutionarily conserved NF-kappaB pathway recognizing meso-diaminopimelic acid (DAP)-type peptidoglycan from bacterial cell walls. Several reviews already provide a detailed view of ligand recognition and signal transduction during Imd signaling, but the formation and regulation of the signaling complex immediately downstream of the peptidoglycan-sensing receptors is still elusive. In this review, we focus on the formation of the Imd amyloidal signaling center and post-translational modifications in the assembly and disassembly of the Imd signaling complex.


Ouabain Enhances Cell-Cell Adhesion Mediated By Beta1 Subunits Of The Na(+),K(+)-Atpase In Cho Fibroblasts, Claudia Andrea Vilchis-Nestor, Maria Luisa Roldan, Angelina Leonardi, Juan G. Navea, Teresita Padilla-Benavides, Liora Shoshani Apr 2019

Ouabain Enhances Cell-Cell Adhesion Mediated By Beta1 Subunits Of The Na(+),K(+)-Atpase In Cho Fibroblasts, Claudia Andrea Vilchis-Nestor, Maria Luisa Roldan, Angelina Leonardi, Juan G. Navea, Teresita Padilla-Benavides, Liora Shoshani

Open Access Articles

Adhesion is a crucial characteristic of epithelial cells to form barriers to pathogens and toxic substances from the environment. Epithelial cells attach to each other using intercellular junctions on the lateral membrane, including tight and adherent junctions, as well as the Na(+),K(+)-ATPase. Our group has shown that non-adherent chinese hamster ovary (CHO) cells transfected with the canine beta1 subunit become adhesive, and those homotypic interactions amongst beta1 subunits of the Na(+),K(+)-ATPase occur between neighboring epithelial cells. Ouabain, a cardiotonic steroid, binds to the alpha subunit of the Na(+),K(+)-ATPase, inhibits the pump activity and induces ...


Exercise Rescues Gene Pathways Involved In Vascular Expansion And Promotes Functional Angiogenesis In Subcutaneous White Adipose Tissue, So Yun Min, Heather Learnard, Shashi Kant, Olga Gaelikman, Raziel Rojas-Rodriguez, Tiffany Desouza, Anand Desai, John F. Keaney Jr., Silvia Corvera, Siobhan M. Craige Apr 2019

Exercise Rescues Gene Pathways Involved In Vascular Expansion And Promotes Functional Angiogenesis In Subcutaneous White Adipose Tissue, So Yun Min, Heather Learnard, Shashi Kant, Olga Gaelikman, Raziel Rojas-Rodriguez, Tiffany Desouza, Anand Desai, John F. Keaney Jr., Silvia Corvera, Siobhan M. Craige

Open Access Articles

Exercise mitigates chronic diseases such as diabetes, cardiovascular diseases, and obesity; however, the molecular mechanisms governing protection from these diseases are not completely understood. Here we demonstrate that exercise rescues metabolically compromised high fat diet (HFD) fed mice, and reprograms subcutaneous white adipose tissue (scWAT). Using transcriptomic profiling, scWAT was analyzed for HFD gene expression changes that were rescued by exercise. Gene networks involved in vascularization were identified as prominent targets of exercise, which led us to investigate the vasculature architecture and endothelial phenotype. Vascular density in scWAT was found to be compromised in HFD, and exercise rescued this defect ...


The Nua4 Acetyltransferase And Histone H4 Acetylation Promote Replication Recovery After Topoisomerase I-Poisoning, Chiaki Noguchi, Tanu Singh, Melissa A. Ziegler, Jasmine D. Peake, Lyne Khair, Ana Aza, Toru M. Nakamura, Eishi Noguchi Apr 2019

The Nua4 Acetyltransferase And Histone H4 Acetylation Promote Replication Recovery After Topoisomerase I-Poisoning, Chiaki Noguchi, Tanu Singh, Melissa A. Ziegler, Jasmine D. Peake, Lyne Khair, Ana Aza, Toru M. Nakamura, Eishi Noguchi

Open Access Articles

BACKGROUND: Histone acetylation plays an important role in DNA replication and repair because replicating chromatin is subject to dynamic changes in its structures. However, its precise mechanism remains elusive. In this report, we describe roles of the NuA4 acetyltransferase and histone H4 acetylation in replication fork protection in the fission yeast Schizosaccharomyces pombe.

RESULTS: Downregulation of NuA4 subunits renders cells highly sensitive to camptothecin, a compound that induces replication fork breakage. Defects in NuA4 function or mutations in histone H4 acetylation sites lead to impaired recovery of collapsed replication forks and elevated levels of Rad52 DNA repair foci, indicating the ...


The Erk Mapk Pathway Is Essential For Skeletal Development And Homeostasis, Jung-Min Kim, Yeon-Suk Yang, Kwang Hwan Park, Hwanhee Oh, Matthew B. Greenblatt, Jae-Hyuck Shim Apr 2019

The Erk Mapk Pathway Is Essential For Skeletal Development And Homeostasis, Jung-Min Kim, Yeon-Suk Yang, Kwang Hwan Park, Hwanhee Oh, Matthew B. Greenblatt, Jae-Hyuck Shim

Open Access Articles

Mitogen-activated protein kinases (MAPKs) are a family of protein kinases that function as key signal transducers of a wide spectrum of extracellular stimuli, including growth factors and pro-inflammatory cytokines. Dysregulation of the extracellular signal-regulated kinase (ERK) MAPK pathway is associated with human skeletal abnormalities including Noonan syndrome, neurofibromatosis type 1, and cardiofaciocutaneous syndrome. Here, we demonstrate that ERK activation in osteoprogenitors is required for bone formation during skeletal development and homeostasis. Deletion of Mek1 and Mek2, kinases upstream of ERK MAPK, in osteoprogenitors (Mek1(Osx)Mek2(-/-)), resulted in severe osteopenia and cleidocranial dysplasia (CCD), similar to that seen in humans ...


Aptamers For Diagnostics With Applications For Infectious Diseases, Muslum Ilgu, Rezzan Fazlioglu, Meric Ozturk, Yasemin Ozsurekci, Marit Nilsen-Hamilton Apr 2019

Aptamers For Diagnostics With Applications For Infectious Diseases, Muslum Ilgu, Rezzan Fazlioglu, Meric Ozturk, Yasemin Ozsurekci, Marit Nilsen-Hamilton

Biochemistry, Biophysics and Molecular Biology Publications

Aptamers are in vitro selected oligonucleotides (DNA, RNA, oligos with modified nucleotides) that can have high affinity and specificity for a broad range of potential targets with high affinity and specificity. Here we focus on their applications as biosensors in the diagnostic field, although they can also be used as therapeutic agents. A small number of peptide aptamers have also been identified. In analytical settings, aptamers have the potential to extend the limit of current techniques as they offer many advantages over antibodies and can be used for real-time biomarker detection, cancer clinical testing, and detection of infectious microorganisms and ...


The Er-Localized Protein Dfcp1 Modulates Er-Lipid Droplet Contact Formation, Dongfang Li, Yan G. Zhao, Di Li, Hongyu Zhao, Jie Huang, Guangyan Miao, Du Feng, Pingsheng Liu, Dong Li, Hong Zhang Apr 2019

The Er-Localized Protein Dfcp1 Modulates Er-Lipid Droplet Contact Formation, Dongfang Li, Yan G. Zhao, Di Li, Hongyu Zhao, Jie Huang, Guangyan Miao, Du Feng, Pingsheng Liu, Dong Li, Hong Zhang

Open Access Articles

Very little is known about the spatiotemporal generation of lipid droplets (LDs) from the endoplasmic reticulum (ER) and the factors that mediate ER-LD contacts for LD growth. Using super-resolution grazing incidence structured illumination microscopy (GI-SIM) live-cell imaging, we reveal that upon LD induction, the ER-localized protein DFCP1 redistributes to nascent puncta on the ER, whose formation depends on triglyceride synthesis. These structures move along the ER and fuse to form expanding LDs. Fusion and expansion of DFCP1-labeled nascent structures is controlled by BSCL2. BSCL2 depletion causes accumulation of nascent DFCP1 structures. DFCP1 overexpression increases LD size and enhances ER-LD contacts ...


Transfer Rna Genes Affect Chromosome Structure And Function Via Local Effects, Omar Hamdani, Tsung-Han S. Hsieh, Oliver J. Rando, Rohinton T. Kamakaka Apr 2019

Transfer Rna Genes Affect Chromosome Structure And Function Via Local Effects, Omar Hamdani, Tsung-Han S. Hsieh, Oliver J. Rando, Rohinton T. Kamakaka

Open Access Articles

The genome is packaged and organized in an ordered, non-random manner and specific chromatin segments contact nuclear substructures to mediate this organization. Transfer RNA genes (tDNAs) are binding sites for transcription factors and architectural proteins and are thought to play an important role in the organization of the genome. In this study, we investigate the role of tDNAs in genomic organization and chromosome function by editing a chromosome so that it lacks any tDNAs. Surprisingly our analyses of this tDNA-less chromosome show that loss of tDNAs does not grossly affect chromatin architecture or chromosome tethering and mobility. However, loss of ...


Determining The Key Residues For Capsule Production In The Gbs Cpsa Protein, Anna Struba Apr 2019

Determining The Key Residues For Capsule Production In The Gbs Cpsa Protein, Anna Struba

Honors College

Streptococcus agalactiae (GBS) is a common bacterium found commensally in the vaginal mucosa of healthy adults. GBS also causes severe infection in neonates, often leading to meningitis, which can cause lifelong health consequences including impaired hearing and seizures. Infection of newborns mainly arises from a colonized mother, either before birth through ascending infection or during labor. Ascending infection, where the bacteria travel to the fetus from the vaginal mucosa, is especially concerning as it can lead to loss of pregnancy or premature birth. The most common method of neonatal GBS disease prevention is antibiotic prophylaxis during delivery, though this method ...


Genome-Wide Prediction Of Synthetic Rescue Mediators Of Resistance To Targeted And Immunotherapy, Avinash Das Sahu, Olga Ponomarova, Eytan Ruppin Mar 2019

Genome-Wide Prediction Of Synthetic Rescue Mediators Of Resistance To Targeted And Immunotherapy, Avinash Das Sahu, Olga Ponomarova, Eytan Ruppin

Open Access Articles

Most patients with advanced cancer eventually acquire resistance to targeted therapies, spurring extensive efforts to identify molecular events mediating therapy resistance. Many of these events involve synthetic rescue (SR) interactions, where the reduction in cancer cell viability caused by targeted gene inactivation is rescued by an adaptive alteration of another gene (the rescuer). Here, we perform a genome-wide in silico prediction of SR rescuer genes by analyzing tumor transcriptomics and survival data of 10,000 TCGA cancer patients. Predicted SR interactions are validated in new experimental screens. We show that SR interactions can successfully predict cancer patients' response and emerging ...


Development Of An Innovative And Sustainable One-Step Method For Rapid Plant Dna Isolation For Targeted Pcr Using Magnetic Ionic Liquids, Arianna Marengo, Cecilia Cagliero, Barbara Sgorbini, Jared L. Anderson, Miranda N. Emaus, Carlo Bicchi, Cinzia M. Bertea, Patrizia Rubiolo Mar 2019

Development Of An Innovative And Sustainable One-Step Method For Rapid Plant Dna Isolation For Targeted Pcr Using Magnetic Ionic Liquids, Arianna Marengo, Cecilia Cagliero, Barbara Sgorbini, Jared L. Anderson, Miranda N. Emaus, Carlo Bicchi, Cinzia M. Bertea, Patrizia Rubiolo

Chemistry Publications

Background

Nowadays, there is an increasing demand for fast and reliable plant biomolecular analyses. Conventional methods for the isolation of nucleic acids are time-consuming and require multiple and often non-automatable steps to remove cellular interferences, with consequence that sample preparation is the major bottleneck in the bioanalytical workflow. New opportunities have been created by the use of magnetic ionic liquids (MILs) thanks to their affinity for nucleic acids.

Results

In the present study, a MIL-based magnet-assisted dispersive liquid–liquid microextraction (maDLLME) method was optimized for the extraction of genomic DNA from Arabidopsis thaliana (L.) Heynh leaves. MILs containing different metal ...


Anti-Drug Antibody Responses Impair Prophylaxis Mediated By Aav-Delivered Hiv-1 Broadly Neutralizing Antibodies, Matthew R. Gardner, Ina Fetzer, Lisa M. Kattenhorn, Meredith E. Davis-Gardner, Amber S. Zhou, Barnett Alfant, Jesse A. Weber, Hema R. Kondur, Jose M. Martinez-Navio, Sebastian P. Fuchs, Ronald C. Desrosiers, Guangping Gao, Jeffrey D. Lifson, Michael Farzan Mar 2019

Anti-Drug Antibody Responses Impair Prophylaxis Mediated By Aav-Delivered Hiv-1 Broadly Neutralizing Antibodies, Matthew R. Gardner, Ina Fetzer, Lisa M. Kattenhorn, Meredith E. Davis-Gardner, Amber S. Zhou, Barnett Alfant, Jesse A. Weber, Hema R. Kondur, Jose M. Martinez-Navio, Sebastian P. Fuchs, Ronald C. Desrosiers, Guangping Gao, Jeffrey D. Lifson, Michael Farzan

Open Access Articles

Adeno-associated virus (AAV) delivery of potent and broadly neutralizing antibodies (bNAbs is a promising approach for the prevention of HIV-1 infection. The immunoglobulin G (IgG)1 subtype is usually selected for this application, because it efficiently mediates antibody effector functions and has a somewhat longer half-life. However, the use of IgG1-Fc has been associated with the generation of anti-drug antibodies (ADAs) that correlate with loss of antibody expression. In contrast, we have shown that expression of the antibody-like molecule eCD4-Ig bearing a rhesus IgG2-Fc domain showed reduced immunogenicity and completely protected rhesus macaques from simian-HIV (SHIV)-AD8 challenges. To directly ...


Hypomorphic Mutations Of Trip11 Cause Odontochondrodysplasia, Anika Wehrle, John A. Follit, Gregory J. Pazour, Andrea Superti-Furga, Martin Lowe, Ekkehart Lausch Feb 2019

Hypomorphic Mutations Of Trip11 Cause Odontochondrodysplasia, Anika Wehrle, John A. Follit, Gregory J. Pazour, Andrea Superti-Furga, Martin Lowe, Ekkehart Lausch

Open Access Articles

Odontochondrodysplasia (ODCD) is an unresolved genetic disorder of skeletal and dental development. Here, we show that ODCD is caused by hypomorphic TRIP11 mutations, and we identify ODCD as the nonlethal counterpart to achondrogenesis 1A (ACG1A), the known null phenotype in humans. TRIP11 encodes Golgi-associated microtubule-binding protein 210 (GMAP-210), an essential tether protein of the Golgi apparatus that physically interacts with intraflagellar transport 20 (IFT20), a component of the ciliary intraflagellar transport complex B. This association and extraskeletal disease manifestations in ODCD point to a cilium-dependent pathogenesis. However, our functional studies in patient-derived primary cells clearly support a Golgi-based disease mechanism ...


Bridging From Intramuscular To Limb Perfusion Delivery Of Raav: Optimization In A Non-Human Primate Study, Alisha Gruntman, Gwladys Gernoux, Qiushi Tang, Guo-Jie Ye, Dave R. Knop, Gensheng Wang, Janet Benson, Kristen E. Coleman, Allison M. Keeler, Christian Mueller, Louis G. Chicoine, Jeffrey D. Chulay, Terence R. Flotte Feb 2019

Bridging From Intramuscular To Limb Perfusion Delivery Of Raav: Optimization In A Non-Human Primate Study, Alisha Gruntman, Gwladys Gernoux, Qiushi Tang, Guo-Jie Ye, Dave R. Knop, Gensheng Wang, Janet Benson, Kristen E. Coleman, Allison M. Keeler, Christian Mueller, Louis G. Chicoine, Jeffrey D. Chulay, Terence R. Flotte

Open Access Articles

Phase 1 and phase 2 gene therapy trials using intramuscular (IM) administration of a recombinant adeno-associated virus serotype 1 (rAAV1) for replacement of serum alpha-1 antitrypsin (AAT) deficiency have shown long-term (5-year) stable transgene expression at approximately 2% to 3% of therapeutic levels, arguing for the long-term viability of this approach to gene replacement of secreted serum protein deficiencies. However, achieving these levels required 100 IM injections to deliver 135 mL of vector, and further dose escalation is limited by the scalability of direct IM injection. To further advance the dose escalation, we sought to bridge the rAAV-AAT clinical development ...


Rapid Evolution And Conserved Function Of The Pirna Pathway, Swapnil S. Parhad, William E. Theurkauf Jan 2019

Rapid Evolution And Conserved Function Of The Pirna Pathway, Swapnil S. Parhad, William E. Theurkauf

Program in Molecular Medicine Publications and Presentations

Transposons are major genome constituents that can mobilize and trigger mutations, DNA breaks and chromosome rearrangements. Transposon silencing is particularly important in the germline, which is dedicated to transmission of the inherited genome. Piwi-interacting RNAs (piRNAs) guide a host defence system that transcriptionally and post-transcriptionally silences transposons during germline development. While germline control of transposons by the piRNA pathway is conserved, many piRNA pathway genes are evolving rapidly under positive selection, and the piRNA biogenesis machinery shows remarkable phylogenetic diversity. Conservation of core function combined with rapid gene evolution is characteristic of a host-pathogen arms race, suggesting that transposons and ...


Itch Nuclear Translocation And H1.2 Polyubiquitination Negatively Regulate The Dna Damage Response, Lufen Chang, Lei Shen, Hu Zhou, Jing Gao, Hangyi Pan, Li Zheng, Brian Armstrong, Yang Peng, Guang Peng, Binhua P. Zhou, Steven T. Rosen, Binghui Shen Jan 2019

Itch Nuclear Translocation And H1.2 Polyubiquitination Negatively Regulate The Dna Damage Response, Lufen Chang, Lei Shen, Hu Zhou, Jing Gao, Hangyi Pan, Li Zheng, Brian Armstrong, Yang Peng, Guang Peng, Binhua P. Zhou, Steven T. Rosen, Binghui Shen

Molecular and Cellular Biochemistry Faculty Publications

The downregulation of the DNA damage response (DDR) enables aggressive tumors to achieve uncontrolled proliferation against replication stress, but the mechanisms underlying this process in tumors are relatively complex. Here, we demonstrate a mechanism through which a distinct E3 ubiquitin ligase, ITCH, modulates DDR machinery in triple-negative breast cancer (TNBC). We found that expression of a nuclear form of ITCH was significantly increased in human TNBC cell lines and tumor specimens. Phosphorylation of ITCH at Ser257 by AKT led to the nuclear localization of ITCH and ubiquitination of H1.2. The ITCH-mediated polyubiquitination of H1.2 suppressed RNF8/RNF168-dependent formation ...


An Automated Bayesian Pipeline For Rapid Analysis Of Single-Molecule Binding Data, Carlas Smith, Karina Jouravleva, Maximiliaan Huisman, Samson M. Jolly, Phillip D. Zamore, David Grünwald Jan 2019

An Automated Bayesian Pipeline For Rapid Analysis Of Single-Molecule Binding Data, Carlas Smith, Karina Jouravleva, Maximiliaan Huisman, Samson M. Jolly, Phillip D. Zamore, David Grünwald

Open Access Articles

Single-molecule binding assays enable the study of how molecular machines assemble and function. Current algorithms can identify and locate individual molecules, but require tedious manual validation of each spot. Moreover, no solution for high-throughput analysis of single-molecule binding data exists. Here, we describe an automated pipeline to analyze single-molecule data over a wide range of experimental conditions. In addition, our method enables state estimation on multivariate Gaussian signals. We validate our approach using simulated data, and benchmark the pipeline by measuring the binding properties of the well-studied, DNA-guided DNA endonuclease, TtAgo, an Argonaute protein from the Eubacterium Thermus thermophilus. We ...