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Genetic Rescue Of Fragile X Syndrome Links Fmrp Deficiency To Codon Optimality-Dependent Rna Destabilization, Huan Shu, Elisa Donnard, Botao Liu, Joel D. Richter Oct 2019

Genetic Rescue Of Fragile X Syndrome Links Fmrp Deficiency To Codon Optimality-Dependent Rna Destabilization, Huan Shu, Elisa Donnard, Botao Liu, Joel D. Richter

University of Massachusetts Medical School Faculty Publications

Fragile X syndrome (FXS) is caused by inactivation of FMR1 gene and loss of its encoded product the RNA binding protein FMRP, which generally represses translation of its target transcripts in the brain. In mouse models of FXS (i.e., Fmr1 knockout animals; Fmr1 KO), deletion of Cpeb1, which encodes a translational activator, mitigates nearly all pathophysiologies associated with the disorder. Here we reveal unexpected wide-spread dys-regulation of RNA abundance in Fmr1 KO brain cortex and its rescue to normal levels in Fmr1/Cpeb1 double KO mice. Alteration and restoration of RNA levels are the dominant molecular events that drive ...


Fmrp Control Of Ribosome Translocation Promotes Chromatin Modifications And Alternative Splicing Of Neuronal Genes Linked To Autism, Sneha Shah, Gemma Molinaro, Botao Liu, Ruijia Wang, Kimberly M. Huber, Joel D. Richter Oct 2019

Fmrp Control Of Ribosome Translocation Promotes Chromatin Modifications And Alternative Splicing Of Neuronal Genes Linked To Autism, Sneha Shah, Gemma Molinaro, Botao Liu, Ruijia Wang, Kimberly M. Huber, Joel D. Richter

University of Massachusetts Medical School Faculty Publications

Silencing of FMR1 and loss of its gene product FMRP results in Fragile X Syndrome. FMRP binds brain mRNAs and inhibits polypeptide elongation. Using ribosome profiling of the hippocampus, we find that ribosome footprint levels in Fmr1-deficient tissue mostly reflect changes in RNA abundance. Profiling over a time course of ribosome runoff in wildtype tissue reveals a wide range of ribosome translocation rates; on many mRNAs, the ribosomes are stalled. Sucrose gradient ultracentrifugation of hippocampal slices after ribosome runoff reveals that FMRP co-sediments with stalled ribosomes; and its loss results in decline of ribosome stalling on specific mRNAs. One ...


Control Of Cellular Responses To Mechanical Cues Through Yap/Taz Regulation, Ishani Dasgupta, Dannel Mccollum Oct 2019

Control Of Cellular Responses To Mechanical Cues Through Yap/Taz Regulation, Ishani Dasgupta, Dannel Mccollum

Open Access Articles

To perceive their three-dimensional environment, cells and tissues must be able to sense and interpret various physical forces like shear, tensile, and compression stress. These forces can be generated both internally and externally in response to physical properties, like substrate stiffness, cell contractility, and forces generated by adjacent cells. Mechanical cues have important roles in cell fate decisions regarding proliferation, survival, differentiation as well as the processes of tissue regeneration and wound repair (1). Aberrant remodeling of the extracellular space and/or defects in properly responding to mechanical cues likely contributes to various disease states such as fibrosis, muscle diseases ...


Common Nodes Of Virus-Host Interaction Revealed Through An Integrated Network Analysis, Korbinian Bosl, Richard K. Kandasamy Oct 2019

Common Nodes Of Virus-Host Interaction Revealed Through An Integrated Network Analysis, Korbinian Bosl, Richard K. Kandasamy

Open Access Articles

Viruses are one of the major causes of acute and chronic infectious diseases and thus a major contributor to the global burden of disease. Several studies have shown how viruses have evolved to hijack basic cellular pathways and evade innate immune response by modulating key host factors and signaling pathways. A collective view of these multiple studies could advance our understanding of virus-host interactions and provide new therapeutic perspectives for the treatment of viral diseases. Here, we performed an integrative meta-analysis to elucidate the 17 different host-virus interactomes. Network and bioinformatics analyses showed how viruses with small genomes efficiently achieve ...


Highly Structured Homolog Pairing Reflects Functional Organization Of The Drosophila Genome, Jumana Alhaj Abed, Jelena Erceg, Anton Goloborodko, Son C. Nguyen, Ruth B. Mccole, Wren Saylor, Geoffrey Fudenberg, Bryan R. Lajoie, Job Dekker, Leonid A. Mirny, C-Ting Wu Oct 2019

Highly Structured Homolog Pairing Reflects Functional Organization Of The Drosophila Genome, Jumana Alhaj Abed, Jelena Erceg, Anton Goloborodko, Son C. Nguyen, Ruth B. Mccole, Wren Saylor, Geoffrey Fudenberg, Bryan R. Lajoie, Job Dekker, Leonid A. Mirny, C-Ting Wu

Program in Systems Biology Publications and Presentations

Trans-homolog interactions have been studied extensively in Drosophila, where homologs are paired in somatic cells and transvection is prevalent. Nevertheless, the detailed structure of pairing and its functional impact have not been thoroughly investigated. Accordingly, we generated a diploid cell line from divergent parents and applied haplotype-resolved Hi-C, showing that homologs pair with varying precision genome-wide, in addition to establishing trans-homolog domains and compartments. We also elucidate the structure of pairing with unprecedented detail, observing significant variation across the genome and revealing at least two forms of pairing: tight pairing, spanning contiguous small domains, and loose pairing, consisting of single ...


Distinct Transcriptional Roles For Histone H3-K56 Acetylation During The Cell Cycle In Yeast, Salih Topal, Pauline Vasseur, Marta Radman-Livaja, Craig L. Peterson Sep 2019

Distinct Transcriptional Roles For Histone H3-K56 Acetylation During The Cell Cycle In Yeast, Salih Topal, Pauline Vasseur, Marta Radman-Livaja, Craig L. Peterson

Open Access Articles

Dynamic disruption and reassembly of promoter-proximal nucleosomes is a conserved hallmark of transcriptionally active chromatin. Histone H3-K56 acetylation (H3K56Ac) enhances these turnover events and promotes nucleosome assembly during S phase. Here we sequence nascent transcripts to investigate the impact of H3K56Ac on transcription throughout the yeast cell cycle. We find that H3K56Ac is a genome-wide activator of transcription. While H3K56Ac has a major impact on transcription initiation, it also appears to promote elongation and/or termination. In contrast, H3K56Ac represses promiscuous transcription that occurs immediately following replication fork passage, in this case by promoting efficient nucleosome assembly. We also detect ...


Oligogenic Effects Of 16p11.2 Copy-Number Variation On Craniofacial Development, Yuqi Qiu, Curtis K. Deutsch, Jonathan Sebat Sep 2019

Oligogenic Effects Of 16p11.2 Copy-Number Variation On Craniofacial Development, Yuqi Qiu, Curtis K. Deutsch, Jonathan Sebat

Open Access Articles

A copy-number variant (CNV) of 16p11.2 encompassing 30 genes is associated with developmental and psychiatric disorders, head size, and body mass. The genetic mechanisms that underlie these associations are not understood. To determine the influence of 16p11.2 genes on development, we investigated the effects of CNV on craniofacial structure in humans and model organisms. We show that deletion and duplication of 16p11.2 have "mirror" effects on specific craniofacial features that are conserved between human and rodent models of the CNV. By testing dosage effects of individual genes on the shape of the mandible in zebrafish, we identify ...


Mutations In The Sptlc1 Gene Are A Cause Of Amyotrophic Lateral Sclerosis That May Be Amenable To Serine Supplementation, Janel O. Johnson, Ruth Chia, Robert H. Brown Jr., John E. Landers Sep 2019

Mutations In The Sptlc1 Gene Are A Cause Of Amyotrophic Lateral Sclerosis That May Be Amenable To Serine Supplementation, Janel O. Johnson, Ruth Chia, Robert H. Brown Jr., John E. Landers

University of Massachusetts Medical School Faculty Publications

SPTLC1 encodes a critical subunit of serine palmitoyltransferase, the enzyme catalyzing the first and rate-limiting step in de novo sphingolipid biosynthesis, and mutations in this gene are known to cause hereditary sensory autonomic neuropathy, type 1A. Using exome sequencing, we identified a de novo variant in SPTLC1 resulting in a p.Ala20Ser amino acid change in an individual diagnosed with juvenile-onset amyotrophic lateral sclerosis (ALS) and confirmed its pathogenicity by showing elevated plasma levels of neurotoxic deoxymethyl-sphinganine. A second case of juvenile-onset ALS arising again from a p.Ala20Ser mutation was later identified, confirming the association of SPTLC1 with this ...


Signaling To Trp53 And Tap63 From Chk1/Chk2 Is Responsible For Elimination Of Most Oocytes Defective For Either Chromosome Synapsis Or Recombination, Vera D. Rinaldi, Jordana C. Bloom, John C. Schimenti Sep 2019

Signaling To Trp53 And Tap63 From Chk1/Chk2 Is Responsible For Elimination Of Most Oocytes Defective For Either Chromosome Synapsis Or Recombination, Vera D. Rinaldi, Jordana C. Bloom, John C. Schimenti

University of Massachusetts Medical School Faculty Publications

Eukaryotic organisms have evolved mechanisms to prevent the accumulation of cells bearing genetic aberrations. This is especially crucial for the germline, because fecundity, and fitness of progeny would be adversely affected by an excessively high mutational incidence. The process of meiosis poses unique problems for mutation avoidance, due to the requirement for SPO11-induced programmed double strand breaks (DSBs) in recombination-driven pairing and segregation of homologous chromosomes. Mouse meiocytes bearing unrepaired meiotic DSBs or unsynapsed chromosomes are eliminated before completing meiotic prophase I. In previous work, we showed that checkpoint kinase 2 (CHK2; CHEK2), a canonical DNA damage response protein, is ...


Co-Option Of The Gibbon-Specific Lava Retrotransposon In Dna Repair Pathways, Mariam Okhovat, Kimberly A. Nevonen, Brett Davis, Pryce S. Michener, Samantha Ward, Mark Milhaven, Lana Harshman, Ajuni Sohota, Rachel J. O’Neill, Nadav Ahituv, Krishna R. Veeramah, Lucia Carbone Sep 2019

Co-Option Of The Gibbon-Specific Lava Retrotransposon In Dna Repair Pathways, Mariam Okhovat, Kimberly A. Nevonen, Brett Davis, Pryce S. Michener, Samantha Ward, Mark Milhaven, Lana Harshman, Ajuni Sohota, Rachel J. O’Neill, Nadav Ahituv, Krishna R. Veeramah, Lucia Carbone

University of Massachusetts Medical School Faculty Publications

Transposable elements (TEs) can shape gene regulation networks by being co-opted as enhancers. However, the contribution of lineage-specific TE insertions to recent adaptations remains poorly understood. Gibbons present a suitable model to study these contributions, as they have evolved many distinct traits, including heavily rearranged genomes and a novel TE called LAVA. The LAVA retrotransposon is still active in the gibbon genome and is thought to have contributed to evolution of gibbon-specific traits. In this study, we characterized fixed and polymorphic LAVA insertions across multiple gibbon genomes and found that 10% of all LAVA elements overlap chromatin states associated with ...


Human Glb1 Knockout Cerebral Organoids: A Model System For Testing Aav9-Mediated Glb1 Gene Therapy For Reducing Gm1 Ganglioside Storage In Gm1 Gangliosidosis, Yvonne L. Latour, Robin Yoon, Sarah E. Thomas, Christina Grant, Cuiling Li, Miguel Sena-Esteves, Maria L. Allende, Richard L. Proia, Cynthia J. Tifft Sep 2019

Human Glb1 Knockout Cerebral Organoids: A Model System For Testing Aav9-Mediated Glb1 Gene Therapy For Reducing Gm1 Ganglioside Storage In Gm1 Gangliosidosis, Yvonne L. Latour, Robin Yoon, Sarah E. Thomas, Christina Grant, Cuiling Li, Miguel Sena-Esteves, Maria L. Allende, Richard L. Proia, Cynthia J. Tifft

Open Access Articles

GM1 gangliosidosis is an autosomal recessive neurodegenerative disorder caused by the deficiency of lysosomal gangliosidebeta-galactosidase (beta-gal) and resulting in accumulation of GM1 ganglioside. The disease spectrum ranges from infantile to late onset and is uniformly fatal, with no effective therapy currently available. Although animal models have been useful for understanding disease pathogenesis and exploring therapeutic targets, no relevant human central nervous system (CNS) model system has been available to study its early pathogenic events or test therapies. To develop a model of human GM1 gangliosidosis in the CNS, we employed CRISPR/Cas9 genome editing to target GLB1 exons 2 and ...


Chitosan Biosynthesis And Virulence In The Human Fungal Pathogen Cryptococcus Gattii, Woei C. Lam, Rajendra Upadhya, Charles A. Specht, Abigail E. Ragsdale, Camaron R. Hole, Stuart M. Levitz, Jennifer K. Lodge Sep 2019

Chitosan Biosynthesis And Virulence In The Human Fungal Pathogen Cryptococcus Gattii, Woei C. Lam, Rajendra Upadhya, Charles A. Specht, Abigail E. Ragsdale, Camaron R. Hole, Stuart M. Levitz, Jennifer K. Lodge

University of Massachusetts Medical School Faculty Publications

Cryptococcus gattii R265 is a hyper-virulent fungal strain responsible for the major outbreak of cryptococcosis in Vancouver Island of British Columbia in 1999. It differs significantly from C. neoformans in its natural environment, its preferred site in the mammalian host, and in the nature and mode of pathogenesis. Our previous studies in C. neoformans have shown that the presence of chitosan, the deacetylated form of chitin, in the cell wall attenuates inflammatory responses in the host, while its absence induces robust immune responses, which in turn facilitate clearance of the fungus and induces a protective response. The results of the ...


Microrna-138 Is A Prognostic Biomarker For Triple-Negative Breast Cancer And Promotes Tumorigenesis Via Tusc2 Repression, Srikanth Nama, Manish Muhuri, Federica Di Pascale, Shan Quah, Luay Aswad, Melissa Fullwood, Prabha Sampath Sep 2019

Microrna-138 Is A Prognostic Biomarker For Triple-Negative Breast Cancer And Promotes Tumorigenesis Via Tusc2 Repression, Srikanth Nama, Manish Muhuri, Federica Di Pascale, Shan Quah, Luay Aswad, Melissa Fullwood, Prabha Sampath

Open Access Articles

Breast cancer manifests as a spectrum of subtypes with distinct molecular signatures, and different responses to treatment. Of these subtypes, triple-negative breast cancer (TNBC) has the worst prognoses and limited therapeutic options. Here we report aberrant expression of microRNA-138 (miR-138) in TNBC. Increased miR-138 expression is highly specific to this subtype, correlates with poor prognosis in patients, and is functionally relevant to cancer progression. Our findings establish miR-138 as a specific diagnostic and prognostic biomarker for TNBC. OncomiR-138 is pro-survival; sequence-specific miR-138 inhibition blocks proliferation, promotes apoptosis and inhibits tumour growth in-vivo. miR-138 directly targets a suite of pro-apoptotic and ...


The Aminoalkylindole, Bml-190, Negatively Regulates Chitosan Synthesis Via The Camp/Pka1 Pathway In Cryptococcus Neoformans, Brian T. Maybruck, Woei C. Lam, Charles A. Specht, Ma Xenia G. Ilagan, Maureen J. Donlin, Jennifer K. Lodge Aug 2019

The Aminoalkylindole, Bml-190, Negatively Regulates Chitosan Synthesis Via The Camp/Pka1 Pathway In Cryptococcus Neoformans, Brian T. Maybruck, Woei C. Lam, Charles A. Specht, Ma Xenia G. Ilagan, Maureen J. Donlin, Jennifer K. Lodge

University of Massachusetts Medical School Faculty Publications

Cryptococcus neoformans can cause fatal meningoencephalitis in patients with AIDS or other immune-compromising conditions. Current antifungals are suboptimal to treat this disease, therefore, novel targets and new therapies are needed. Previously, we have shown that chitosan is a critical component of the cryptococcal cell wall, is required for survival in the mammalian host, and that chitosan deficiency results in rapid clearance from the mammalian host. We had also identified several specific proteins that were required for chitosan biosynthesis, and we hypothesize that screening for compounds that inhibit chitosan biosynthesis would identify additional genes/proteins that influence chitosan biosynthesis.


A Unified Encyclopedia Of Human Functional Dna Elements Through Fully Automated Annotation Of 164 Human Cell Types, Maxwell W. Libbrecht, Oscar L. Rodriguez, Zhiping Weng, Jeffrey A. Bilmes, Michael M. Hoffman, William Stafford Noble Aug 2019

A Unified Encyclopedia Of Human Functional Dna Elements Through Fully Automated Annotation Of 164 Human Cell Types, Maxwell W. Libbrecht, Oscar L. Rodriguez, Zhiping Weng, Jeffrey A. Bilmes, Michael M. Hoffman, William Stafford Noble

Open Access Articles

Semi-automated genome annotation methods such as Segway take as input a set of genome-wide measurements such as of histone modification or DNA accessibility and output an annotation of genomic activity in the target cell type. Here we present annotations of 164 human cell types using 1615 data sets. To produce these annotations, we automated the label interpretation step to produce a fully automated annotation strategy. Using these annotations, we developed a measure of the importance of each genomic position called the "conservation-associated activity score." We further combined all annotations into a single, cell type-agnostic encyclopedia that catalogs all human regulatory ...


Modeling Of Cisplatin-Induced Signaling Dynamics In Triple-Negative Breast Cancer Cells Reveals Mediators Of Sensitivity, Anne Margriet Heijink, Marieke Everts, Megan E. Honeywell, Ryan Richards, Yannick P. Kok, Elisabeth G. E. De Vries, Michael J. Lee, Marcel A T M Van Vugt Aug 2019

Modeling Of Cisplatin-Induced Signaling Dynamics In Triple-Negative Breast Cancer Cells Reveals Mediators Of Sensitivity, Anne Margriet Heijink, Marieke Everts, Megan E. Honeywell, Ryan Richards, Yannick P. Kok, Elisabeth G. E. De Vries, Michael J. Lee, Marcel A T M Van Vugt

Open Access Articles

Triple-negative breast cancers (TNBCs) display great diversity in cisplatin sensitivity that cannot be explained solely by cancer-associated DNA repair defects. Differential activation of the DNA damage response (DDR) to cisplatin has been proposed to underlie the observed differential sensitivity, but it has not been investigated systematically. Systems-level analysis-using quantitative time-resolved signaling data and phenotypic responses, in combination with mathematical modeling-identifies that the activation status of cell-cycle checkpoints determines cisplatin sensitivity in TNBC cell lines. Specifically, inactivation of the cell-cycle checkpoint regulator MK2 or G3BP2 sensitizes cisplatin-resistant TNBC cell lines to cisplatin. Dynamic signaling data of five cell cycle-related signals predicts ...


Pax9 Is Required For Cardiovascular Development And Interacts With Tbx1 In The Pharyngeal Endoderm To Control 4(Th) Pharyngeal Arch Artery Morphogenesis, Helen M. Phillips, Rene Maehr, Simon D. Bamforth Aug 2019

Pax9 Is Required For Cardiovascular Development And Interacts With Tbx1 In The Pharyngeal Endoderm To Control 4(Th) Pharyngeal Arch Artery Morphogenesis, Helen M. Phillips, Rene Maehr, Simon D. Bamforth

Open Access Articles

Developmental defects affecting the heart and aortic arch arteries are a significant phenotype observed in 22q11 deletion syndrome patients and are caused by a microdeletion on chromosome 22q11. TBX1, one of the deleted genes, is expressed throughout the pharyngeal arches and is considered a key gene, when mutated, for the arch artery defects. Pax9 is expressed in the pharyngeal endoderm and is downregulated in Tbx1 mutant mice. We show here that Pax9 deficient mice are born with complex cardiovascular malformations affecting the outflow tract and aortic arch arteries with failure of the 3(rd) and 4(th) pharyngeal arch arteries ...


Modulation Of Actin Polymerization Affects Nucleocytoplasmic Transport In Multiple Forms Of Amyotrophic Lateral Sclerosis, Anthony Giampetruzzi, Eric W. Danielson, Valentina Gumina, Maryangel Jeon, Sivakumar Boopathy, Robert H. Brown Jr., Antonia Ratti, John E. Landers, Claudia Fallini Aug 2019

Modulation Of Actin Polymerization Affects Nucleocytoplasmic Transport In Multiple Forms Of Amyotrophic Lateral Sclerosis, Anthony Giampetruzzi, Eric W. Danielson, Valentina Gumina, Maryangel Jeon, Sivakumar Boopathy, Robert H. Brown Jr., Antonia Ratti, John E. Landers, Claudia Fallini

Open Access Articles

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease of unknown etiology. Although defects in nucleocytoplasmic transport (NCT) may be central to the pathogenesis of ALS and other neurodegenerative diseases, the molecular mechanisms modulating the nuclear pore function are still largely unknown. Here we show that genetic and pharmacological modulation of actin polymerization disrupts nuclear pore integrity, nuclear import, and downstream pathways such as mRNA post-transcriptional regulation. Importantly, we demonstrate that modulation of actin homeostasis can rescue nuclear pore instability and dysfunction caused by mutant PFN1 as well as by C9ORF72 repeat expansion, the most common mutation in ALS patients ...


Gain-Of-Function Mutations In The Unc-2/Cav2alpha Channel Lead To Excitation-Dominant Synaptic Transmission In C. Elegans, Yung-Chi Huang, Jennifer K. Pirri, Diego Rayes, Shangbang Gao, Ben Mulcahy, Jeff Grant, Yasunori Saheki, Michael M. Francis, Mei Zhen, Mark J. Alkema Aug 2019

Gain-Of-Function Mutations In The Unc-2/Cav2alpha Channel Lead To Excitation-Dominant Synaptic Transmission In C. Elegans, Yung-Chi Huang, Jennifer K. Pirri, Diego Rayes, Shangbang Gao, Ben Mulcahy, Jeff Grant, Yasunori Saheki, Michael M. Francis, Mei Zhen, Mark J. Alkema

Neurobiology Publications and Presentations

Mutations in pre-synaptic voltage gated calcium channels can lead to familial hemiplegic migraine type 1 (FHM1). While mammalian studies indicate that the migraine brain is hyperexcitable due to enhanced excitation or reduced inhibition, the molecular and cellular mechanisms underlying this excitatory/inhibitory (E/I) imbalance are poorly understood. We identified a gain-of-function (gf) mutation in the Caenorhabditis elegans CaV2 channel alpha1 subunit, UNC-2, which leads to increased calcium currents. unc-2(zf35gf) mutants exhibit hyperactivity and seizure-like motor behaviors. Expression of the unc-2 gene with FHM1 substitutions R192Q and S218L leads to hyperactivity similar to that of unc-2(zf35gf) mutants. unc-2 ...


Tale And Nf-Y Co-Occupancy Marks Enhancers Of Developmental Control Genes During Zygotic Genome Activation In Zebrafish, William J. Stanney Iii, Franck Ladam, Ian J. Donaldson, Teagan J. Parsons, Rene Maehr, Nicoletta Bobola, Charles G. Sagerstrom Jul 2019

Tale And Nf-Y Co-Occupancy Marks Enhancers Of Developmental Control Genes During Zygotic Genome Activation In Zebrafish, William J. Stanney Iii, Franck Ladam, Ian J. Donaldson, Teagan J. Parsons, Rene Maehr, Nicoletta Bobola, Charles G. Sagerstrom

University of Massachusetts Medical School Faculty Publications

Animal embryogenesis is initiated by maternal factors, but zygotic genome activation (ZGA) shifts control to the embryo at early blastula stages. ZGA is thought to be mediated by specialized maternally deposited transcription factors (TFs), but here we demonstrate that NF-Y and TALE – TFs with known later roles in embryogenesis – co-occupy unique genomic elements at zebrafish ZGA. We show that these elements are selectively associated with early-expressed genes involved in transcriptional regulation and possess enhancer activity in vivo. In contrast, we find that elements individually occupied by either NF-Y or TALE are associated with genes acting later in development – such that ...


Common Variants In The Glycerol Kinase Gene Reduce Tuberculosis Drug Efficacy, Michelle M. Bellerose, Seung-Hun Baek, Chuan-Chin Huang, Caitlin E. Moss, Eun-Ik Koh, Megan K. Proulx, Clare M. Smith, Richard E. Baker, Jong Seok Lee, Seokyong Eum, Sung Jae Shin, Sang-Nae Cho, Megan Murray, Christopher M. Sassetti Jul 2019

Common Variants In The Glycerol Kinase Gene Reduce Tuberculosis Drug Efficacy, Michelle M. Bellerose, Seung-Hun Baek, Chuan-Chin Huang, Caitlin E. Moss, Eun-Ik Koh, Megan K. Proulx, Clare M. Smith, Richard E. Baker, Jong Seok Lee, Seokyong Eum, Sung Jae Shin, Sang-Nae Cho, Megan Murray, Christopher M. Sassetti

Open Access Articles

Despite the administration of multiple drugs that are highly effective in vitro, tuberculosis (TB) treatment requires prolonged drug administration and is confounded by the emergence of drug-resistant strains. To understand the mechanisms that limit antibiotic efficacy, we performed a comprehensive genetic study to identify Mycobacterium tuberculosis genes that alter the rate of bacterial clearance in drug-treated mice. Several functionally distinct bacterial genes were found to alter bacterial clearance, and prominent among these was the glpK gene that encodes the glycerol-3-kinase enzyme that is necessary for glycerol catabolism. Growth on glycerol generally increased the sensitivity of M. tuberculosis to antibiotics in ...


Effective Mismatch Repair Depends On Timely Control Of Pcna Retention On Dna By The Elg1 Complex, Lovely Jael Paul Solomon Devakumar, Christl Gaubitz, Victoria Lundblad, Brian A. Kelch, Takashi Kubota Jul 2019

Effective Mismatch Repair Depends On Timely Control Of Pcna Retention On Dna By The Elg1 Complex, Lovely Jael Paul Solomon Devakumar, Christl Gaubitz, Victoria Lundblad, Brian A. Kelch, Takashi Kubota

Open Access Articles

Proliferating cell nuclear antigen (PCNA) is a sliding clamp that acts as a central co-ordinator for mismatch repair (MMR) as well as DNA replication. Loss of Elg1, the major subunit of the PCNA unloader complex, causes over-accumulation of PCNA on DNA and also increases mutation rate, but it has been unclear if the two effects are linked. Here we show that timely removal of PCNA from DNA by the Elg1 complex is important to prevent mutations. Although premature unloading of PCNA generally increases mutation rate, the mutator phenotype of elg1Delta is attenuated by PCNA mutants PCNA-R14E and PCNA-D150E that spontaneously ...


Nonnative Structure In A Peptide Model Of The Unfolded State Of Sod1: Implications For Als-Linked Aggregation, Noah R. Cohen, Jill A. Zitzewitz, Osman Bilsel, C. Robert Matthews Jul 2019

Nonnative Structure In A Peptide Model Of The Unfolded State Of Sod1: Implications For Als-Linked Aggregation, Noah R. Cohen, Jill A. Zitzewitz, Osman Bilsel, C. Robert Matthews

Open Access Articles

Dozens of mutations throughout the sequence of the gene encoding superoxide dismutase 1 (SOD1) have been linked to toxic protein aggregation in the neurodegenerative disease amyotrophic lateral sclerosis (ALS). A parsimonious explanation for numerous genotypes resulting in a common phenotype would be mutation-induced perturbation of the folding free-energy surface that increases the populations of high-energy states prone to aggregation. The absence of intermediates in the folding of monomeric SOD1 suggests that the unfolded ensemble is a potential source of aggregation. To test this hypothesis, here we dissected SOD1 into a set of peptides end-labeled with FRET probes to model the ...


Alternative Splicing Regulates Stochastic Nlrp3 Activity, Florian Hoss, James L. Mueller, Francisca Rojas Ringeling, Juan F. Rodriguez-Alcazar, Rebecca Brinkschulte, Gerald Seifert, Rainer Stahl, Lori Broderick, Chris D. Putnam, Richard D. Kolodner, Stefan Canzar, Matthias Geyer, Hal M. Hoffman, Eicke Latz Jul 2019

Alternative Splicing Regulates Stochastic Nlrp3 Activity, Florian Hoss, James L. Mueller, Francisca Rojas Ringeling, Juan F. Rodriguez-Alcazar, Rebecca Brinkschulte, Gerald Seifert, Rainer Stahl, Lori Broderick, Chris D. Putnam, Richard D. Kolodner, Stefan Canzar, Matthias Geyer, Hal M. Hoffman, Eicke Latz

Open Access Articles

Leucine-rich repeat (LRR) domains are evolutionarily conserved in proteins that function in development and immunity. Here we report strict exonic modularity of LRR domains of several human gene families, which is a precondition for alternative splicing (AS). We provide evidence for AS of LRR domain within several Nod-like receptors, most prominently the inflammasome sensor NLRP3. Human NLRP3, but not mouse NLRP3, is expressed as two major isoforms, the full-length variant and a variant lacking exon 5. Moreover, NLRP3 AS is stochastically regulated, with NLRP3 exon 5 lacking the interaction surface for NEK7 and hence loss of activity. Our data thus ...


Inactivating Mutations And X-Ray Crystal Structure Of The Tumor Suppressor Opcml Reveal Cancer-Associated Functions, James R. Birtley, Zachary Maben, Grant C. Weaver, Mollie M. Jurewicz, Lawrence J. Stern, Chiara Recchi, Hani Gabra Jul 2019

Inactivating Mutations And X-Ray Crystal Structure Of The Tumor Suppressor Opcml Reveal Cancer-Associated Functions, James R. Birtley, Zachary Maben, Grant C. Weaver, Mollie M. Jurewicz, Lawrence J. Stern, Chiara Recchi, Hani Gabra

Open Access Articles

OPCML, a tumor suppressor gene, is frequently silenced epigenetically in ovarian and other cancers. Here we report, by analysis of databases of tumor sequences, the observation of OPCML somatic missense mutations from various tumor types and the impact of these mutations on OPCML function, by solving the X-ray crystal structure of this glycoprotein to 2.65 A resolution. OPCML consists of an extended arrangement of three immunoglobulin-like domains and homodimerizes via a network of contacts between membrane-distal domains. We report the generation of a panel of OPCML variants with representative clinical mutations and demonstrate clear phenotypic effects in vitro and ...


A Receptor Of The Immunoglobulin Superfamily Regulates Adaptive Thermogenesis, Carmen Hurtado Del Pozo, Randall H. Friedline, Hye Lim Noh, Jason K. Kim, Ann Marie. Schmidt Jul 2019

A Receptor Of The Immunoglobulin Superfamily Regulates Adaptive Thermogenesis, Carmen Hurtado Del Pozo, Randall H. Friedline, Hye Lim Noh, Jason K. Kim, Ann Marie. Schmidt

Open Access Articles

Exquisite regulation of energy homeostasis protects from nutrient deprivation but causes metabolic dysfunction upon nutrient excess. In human and murine adipose tissue, the accumulation of ligands of the receptor for advanced glycation end products (RAGE) accompanies obesity, implicating this receptor in energy metabolism. Here, we demonstrate that mice bearing global- or adipocyte-specific deletion of Ager, the gene encoding RAGE, display superior metabolic recovery after fasting, a cold challenge, or high-fat feeding. The RAGE-dependent mechanisms were traced to suppression of protein kinase A (PKA)-mediated phosphorylation of its key targets, hormone-sensitive lipase and p38 mitogen-activated protein kinase, upon beta-adrenergic receptor stimulation-processes ...


Calcineurin Broadly Regulates The Initiation Of Skeletal Muscle-Specific Gene Expression By Binding Target Promoters And Facilitating The Interaction Of The Swi/Snf Chromatin Remodeling Enzyme, Hanna Witwicka, Jumpei Nogami, Sabriya A. Syed, Kazumitsu Maehara, Teresita Padilla-Benavides, Yasuyuki Ohkawa, Anthony N. Imbalzano Jul 2019

Calcineurin Broadly Regulates The Initiation Of Skeletal Muscle-Specific Gene Expression By Binding Target Promoters And Facilitating The Interaction Of The Swi/Snf Chromatin Remodeling Enzyme, Hanna Witwicka, Jumpei Nogami, Sabriya A. Syed, Kazumitsu Maehara, Teresita Padilla-Benavides, Yasuyuki Ohkawa, Anthony N. Imbalzano

Open Access Articles

Calcineurin (Cn) is a calcium-activated serine/threonine protein phosphatase that is broadly implicated in diverse cellular processes, including the regulation of gene expression. During skeletal muscle differentiation, Cn activates the NFAT transcription factor but also promotes differentiation by counteracting the negative influences of protein kinase C beta (PKCbeta) via dephosphorylation and activation of BRG1, an enzymatic subunit of the mammalian SWI/SNF ATP-dependent chromatin remodeling enzyme. Here we identified four major temporal patterns of Cn-dependent gene expression in differentiating myoblasts and determined that Cn is broadly required for the activation of the myogenic gene expression program. Mechanistically, Cn promotes gene ...


Rapid Irreversible Transcriptional Reprogramming In Human Stem Cells Accompanied By Discordance Between Replication Timing And Chromatin Compartment, Vishnu Dileep, Rachel Patton Mccord, Job Dekker, David M. Gilbert Jul 2019

Rapid Irreversible Transcriptional Reprogramming In Human Stem Cells Accompanied By Discordance Between Replication Timing And Chromatin Compartment, Vishnu Dileep, Rachel Patton Mccord, Job Dekker, David M. Gilbert

Open Access Articles

The temporal order of DNA replication is regulated during development and is highly correlated with gene expression, histone modifications and 3D genome architecture. We tracked changes in replication timing, gene expression, and chromatin conformation capture (Hi-C) A/B compartments over the first two cell cycles during differentiation of human embryonic stem cells to definitive endoderm. Remarkably, transcriptional programs were irreversibly reprogrammed within the first cell cycle and were largely but not universally coordinated with replication timing changes. Moreover, changes in A/B compartment and several histone modifications that normally correlate strongly with replication timing showed weak correlation during the early ...


F-Box Protein Fbxo16 Functions As A Tumor Suppressor By Attenuating Nuclear Beta-Catenin Function, Debasish Paul, Sehbanul Islam, Rajesh Kumar. Manne, U. S. Dinesh, Sunil K. Malonia, Biswanath Maity, Ramanamurthy Boppana, Srikanth Rapole, Praveen Kumar Shetty, Manas Kumar Santra Jul 2019

F-Box Protein Fbxo16 Functions As A Tumor Suppressor By Attenuating Nuclear Beta-Catenin Function, Debasish Paul, Sehbanul Islam, Rajesh Kumar. Manne, U. S. Dinesh, Sunil K. Malonia, Biswanath Maity, Ramanamurthy Boppana, Srikanth Rapole, Praveen Kumar Shetty, Manas Kumar Santra

Open Access Articles

Aberrant activation of beta-catenin has been implicated in a variety of human diseases, including cancer. In spite of significant progress, the regulation of active Wnt/beta-catenin-signaling pathways is still poorly understood. In this study, we show that F-box protein 16 (FBXO16) is a putative tumor suppressor. It is a component of the SCF (SKP1-Cullin1-F-box protein) complex, which targets the nuclear beta-catenin protein to facilitate proteasomal degradation through the 26S proteasome. FBXO16 interacts physically with the C-terminal domain of beta-catenin and promotes its lysine 48-linked polyubiquitination. In addition, it inhibits epithelial-to-mesenchymal transition (EMT) by attenuating the level of beta-catenin. Therefore, depletion ...


Adaptive Evolution Targets A Pirna Precursor Transcription Network, Swapnil S. Parhad, Tianxiong Yu, Gen Zhang, Nicholas P. Rice, Zhiping Weng, William E. Theurkauf Jun 2019

Adaptive Evolution Targets A Pirna Precursor Transcription Network, Swapnil S. Parhad, Tianxiong Yu, Gen Zhang, Nicholas P. Rice, Zhiping Weng, William E. Theurkauf

University of Massachusetts Medical School Faculty Publications

In Drosophila, transposon-silencing piRNAs are derived from heterochromatic clusters and a subset of euchromatic transposon insertions, which are transcribed from internal non-canonical initiation sites and flanking canonical promoters. Rhino binds to Deadlock, which recruits TRF2 to promote non-canonical transcription of these loci. Cuff co-localizes with Rhino and Del. The role of Cuff is less well understood, but the cuff gene shows hallmarks of adaptive evolution, which frequently targets functional interactions within host defense systems. We show that Drosophila simulans cuff is a dominant negative allele when expressed in Drosophila melanogaster, where it traps Deadlock, TRF2 and the transcriptional co-repressor CtBP ...