Open Access. Powered by Scholars. Published by Universities.®

Biochemistry, Biophysics, and Structural Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

Physiology

University of Massachusetts Medical School Faculty Publications

Keyword
Publication Year

Articles 1 - 20 of 20

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

The Cjun Nh2-Terminal Kinase (Jnk) Signaling Pathway Promotes Genome Stability And Prevents Tumor Initiation, Nomeda A. Girnius, Yvonne J. K. Edwards, David S. Garlick, Roger J. Davis Jun 2018

The Cjun Nh2-Terminal Kinase (Jnk) Signaling Pathway Promotes Genome Stability And Prevents Tumor Initiation, Nomeda A. Girnius, Yvonne J. K. Edwards, David S. Garlick, Roger J. Davis

University of Massachusetts Medical School Faculty Publications

Breast cancer is the most commonly diagnosed malignancy in women. Analysis of breast cancer genomic DNA indicates frequent loss-of-function mutations in components of the cJUN NH2-terminal kinase (JNK) signaling pathway. Since JNK signaling can promote cell proliferation by activating the AP1 transcription factor, this apparent association of reduced JNK signaling with tumor development was unexpected. We examined the effect of JNK deficiency in the murine breast epithelium. Loss of JNK signaling caused genomic instability and the development of breast cancer. Moreover, JNK deficiency caused widespread early neoplasia and rapid tumor formation in a murine model of breast cancer. This tumor ...


Jip1-Mediated Jnk Activation Negatively Regulates Synaptic Plasticity And Spatial Memory, Caroline Morel, Tessi Sherrin, Norman J. Kennedy, Kelly H. Forest, Seda Barutcu, Michael Robles, Ezekiel Carpenter-Hyland, Naghum Alfulaij, Claire L. Standen, Robert A. Nichols, Morris Benveniste, Roger J. Davis, Cedomir Todorovic Apr 2018

Jip1-Mediated Jnk Activation Negatively Regulates Synaptic Plasticity And Spatial Memory, Caroline Morel, Tessi Sherrin, Norman J. Kennedy, Kelly H. Forest, Seda Barutcu, Michael Robles, Ezekiel Carpenter-Hyland, Naghum Alfulaij, Claire L. Standen, Robert A. Nichols, Morris Benveniste, Roger J. Davis, Cedomir Todorovic

University of Massachusetts Medical School Faculty Publications

The c-Jun N-terminal kinase (JNK) signal transduction pathway is implicated in learning and memory. Here, we examined the role of JNK activation mediated by the JIP1 scaffold protein. We compared male wild-type mice with a mouse model harboring a point mutation in the Jip1 gene that selectively blocks JIP1-mediated JNK activation. These male mutant mice exhibited increased NMDA receptor currents, increased NMDA receptor-mediated gene expression, and a lower threshold for induction of hippocampal long-term potentiation. The JIP1 mutant mice also displayed improved hippocampus-dependent spatial memory and enhanced associative fear conditioning. These results were confirmed using a second JIP1 mutant mouse ...


Multiple Molecular Mechanisms Rescue Mtdna Disease In C. Elegans, Suraiya Haroon, Annie Li, Jaye L. Weinert, Clark Fritsch, Nolan G. Ericson, Jasmine Alexander-Floyd, Bart P. Braeckman, Cole M. Haynes, Jason H. Bielas, Tali Gidalevitz, Marc Vermulst Mar 2018

Multiple Molecular Mechanisms Rescue Mtdna Disease In C. Elegans, Suraiya Haroon, Annie Li, Jaye L. Weinert, Clark Fritsch, Nolan G. Ericson, Jasmine Alexander-Floyd, Bart P. Braeckman, Cole M. Haynes, Jason H. Bielas, Tali Gidalevitz, Marc Vermulst

University of Massachusetts Medical School Faculty Publications

Genetic instability of the mitochondrial genome (mtDNA) plays an important role in human aging and disease. Thus far, it has proven difficult to develop successful treatment strategies for diseases that are caused by mtDNA instability. To address this issue, we developed a model of mtDNA disease in the nematode C. elegans, an animal model that can rapidly be screened for genes and biological pathways that reduce mitochondrial pathology. These worms recapitulate all the major hallmarks of mtDNA disease in humans, including increased mtDNA instability, loss of respiration, reduced neuromuscular function, and a shortened lifespan. We found that these phenotypes could ...


The Cjun Nh2-Terminal Kinase (Jnk) Pathway Contributes To Mouse Mammary Gland Remodeling During Involution, Nomeda A. Girnius, Yvonne J. K. Edwards, Roger J. Davis Mar 2018

The Cjun Nh2-Terminal Kinase (Jnk) Pathway Contributes To Mouse Mammary Gland Remodeling During Involution, Nomeda A. Girnius, Yvonne J. K. Edwards, Roger J. Davis

University of Massachusetts Medical School Faculty Publications

Involution returns the lactating mammary gland to a quiescent state after weaning. The mechanism of involution involves collapse of the mammary epithelial cell compartment. To test whether the cJUN NH2-terminal kinase (JNK) signal transduction pathway contributes to involution, we established mice with JNK deficiency in the mammary epithelium. We found that JNK is required for efficient involution. JNK deficiency did not alter the STAT3/5 or SMAD2/3 signaling pathways that have been previously implicated in this process. Nevertheless, JNK promotes the expression of genes that drive involution, including matrix metalloproteases, cathepsins, and BH3-only proteins. These data demonstrate that JNK ...


Distinct Adipocyte Progenitor Cells Are Associated With Regional Phenotypes Of Perivascular Aortic Fat In Mice, Khanh-Van T. Tran, Timothy P. Fitzgibbons, So Yun Min, Tiffany Desouza, Silvia Corvera Mar 2018

Distinct Adipocyte Progenitor Cells Are Associated With Regional Phenotypes Of Perivascular Aortic Fat In Mice, Khanh-Van T. Tran, Timothy P. Fitzgibbons, So Yun Min, Tiffany Desouza, Silvia Corvera

University of Massachusetts Medical School Faculty Publications

OBJECTIVE: Perivascular adipose tissue depots around the aorta are regionally distinct and have specific functional properties. Thoracic aorta perivascular adipose tissue (tPVAT) expresses higher levels of thermogenic genes and lower levels of inflammatory genes than abdominal aorta perivascular adipose tissue (aPVAT). It is not known whether this distinction is due to the in-vivo functional environment or to cell-autonomous traits that persist outside the in-vivo setting. In this study, we asked whether the progenitor cells in tPVAT and aPVAT have cell-autonomous traits that lead to formation of regionally distinct PVAT.

METHODS: We performed microarray analysis of thoracic and abdominal peri-aortic adipose ...


Upr(Mt) Regulation And Output: A Stress Response Mediated By Mitochondrial-Nuclear Communication, Andrew Melber, Cole M. Haynes Feb 2018

Upr(Mt) Regulation And Output: A Stress Response Mediated By Mitochondrial-Nuclear Communication, Andrew Melber, Cole M. Haynes

University of Massachusetts Medical School Faculty Publications

The mitochondrial network is not only required for the production of energy, essential cofactors and amino acids, but also serves as a signaling hub for innate immune and apoptotic pathways. Multiple mechanisms have evolved to identify and combat mitochondrial dysfunction to maintain the health of the organism. One such pathway is the mitochondrial unfolded protein response (UPR(mt)), which is regulated by the mitochondrial import efficiency of the transcription factor ATFS-1 in C. elegans and potentially orthologous transcription factors in mammals (ATF4, ATF5, CHOP). Upon mitochondrial dysfunction, import of ATFS-1 into mitochondria is reduced, allowing it to be trafficked to ...


Serine-Dependent Sphingolipid Synthesis Is A Metabolic Liability Of Aneuploid Cells, Sunyoung Hwang, H. Tobias Gustafsson, Ciara O'Sullivan, Gianna Bisceglia, Xinhe Huang, Christian Klose, Andrej Schevchenko, Robert C. Dickson, Paola Cavaliere, Noah Dephoure, Eduardo M. Torres Dec 2017

Serine-Dependent Sphingolipid Synthesis Is A Metabolic Liability Of Aneuploid Cells, Sunyoung Hwang, H. Tobias Gustafsson, Ciara O'Sullivan, Gianna Bisceglia, Xinhe Huang, Christian Klose, Andrej Schevchenko, Robert C. Dickson, Paola Cavaliere, Noah Dephoure, Eduardo M. Torres

University of Massachusetts Medical School Faculty Publications

Aneuploidy disrupts cellular homeostasis. However, the molecular mechanisms underlying the physiological responses and adaptation to aneuploidy are not well understood. Deciphering these mechanisms is important because aneuploidy is associated with diseases, including intellectual disability and cancer. Although tumors and mammalian aneuploid cells, including several cancer cell lines, show altered levels of sphingolipids, the role of sphingolipids in aneuploidy remains unknown. Here, we show that ceramides and long-chain bases, sphingolipid molecules that slow proliferation and promote survival, are increased by aneuploidy. Sphingolipid levels are tightly linked to serine synthesis, and inhibiting either serine or sphingolipid synthesis can specifically impair the fitness ...


Loss Of The Cone-Enriched Caspase-7 Does Not Affect Secondary Cone Death In Retinitis Pigmentosa, Aditya Venkatesh, Shun-Yun Cheng, Claudio Punzo Dec 2017

Loss Of The Cone-Enriched Caspase-7 Does Not Affect Secondary Cone Death In Retinitis Pigmentosa, Aditya Venkatesh, Shun-Yun Cheng, Claudio Punzo

University of Massachusetts Medical School Faculty Publications

Purpose: The apoptotic mechanisms responsible for secondary cone death in retinitis pigmentosa (RP) remain largely unknown. The cone-enriched apoptotic protease caspase-7 (Casp7) is thought to be triggered by endoplasmic reticulum (ER) stress and plays a pivotal role in mice deficient in the cone cyclic nucleotide-gated channels, a deficiency that causes achromatopsia in humans and in mice with autosomal dominant rhodopsin mutations, in particular the T17M mutation. Thus, we tested in two mouse models of RP whether the cone-enriched Casp7 plays a role during secondary cone death.

Methods: Casp7 knockout mice were crossed to two different RP mouse models with significantly ...


Hepatic Dysfunction Caused By Consumption Of A High-Fat Diet, Anthony R. Soltis, Norman J. Kennedy, Xiaofeng Xin, Feng Zhou, Scott B. Ficarro, Yoon Sing Yap, Bryan J. Matthews, Douglas A. Lauffenburger, Forest M. White, Jarrod A. Marto, Roger J. Davis, Ernest Fraenkel Dec 2017

Hepatic Dysfunction Caused By Consumption Of A High-Fat Diet, Anthony R. Soltis, Norman J. Kennedy, Xiaofeng Xin, Feng Zhou, Scott B. Ficarro, Yoon Sing Yap, Bryan J. Matthews, Douglas A. Lauffenburger, Forest M. White, Jarrod A. Marto, Roger J. Davis, Ernest Fraenkel

University of Massachusetts Medical School Faculty Publications

Obesity is a major human health crisis that promotes insulin resistance and, ultimately, type 2 diabetes. The molecular mechanisms that mediate this response occur across many highly complex biological regulatory levels that are incompletely understood. Here, we present a comprehensive molecular systems biology study of hepatic responses to high-fat feeding in mice. We interrogated diet-induced epigenomic, transcriptomic, proteomic, and metabolomic alterations using high-throughput omic methods and used a network modeling approach to integrate these diverse molecular signals. Our model indicated that disruption of hepatic architecture and enhanced hepatocyte apoptosis are among the numerous biological processes that contribute to early liver ...


Intraflagellar Transport Protein Ift20 Is Essential For Male Fertility And Spermiogenesis In Mice, Zhengang Zhang, Wei Li, Yong Zhang, Ling Zhang, Maria E. Teves, Hong Liu, Jerome F. Strauss 3rd, Gregory J. Pazour, James A. Foster, Rex A. Hess, Zhibing Zhang Nov 2016

Intraflagellar Transport Protein Ift20 Is Essential For Male Fertility And Spermiogenesis In Mice, Zhengang Zhang, Wei Li, Yong Zhang, Ling Zhang, Maria E. Teves, Hong Liu, Jerome F. Strauss 3rd, Gregory J. Pazour, James A. Foster, Rex A. Hess, Zhibing Zhang

University of Massachusetts Medical School Faculty Publications

Intraflagellar transport (IFT) is a conserved mechanism thought to be essential for the assembly and maintenance of cilia and flagella. However, little is known about its role in mammalian sperm flagella formation. To fill this gap, we disrupted the Ift20 gene in male germ cells. Homozygous mutant mice were infertile with significantly reduced sperm counts and motility. In addition, abnormally shaped elongating spermatid heads and bulbous round spermatids were found in the lumen of the seminiferous tubules. Electron microscopy revealed increased cytoplasmic vesicles, fiber-like structures, abnormal accumulation of mitochondria and a decrease in mature lysosomes. The few developed sperm had ...


Altered Interleukin-10 Signaling In Skeletal Muscle Regulates Obesity-Mediated Inflammation And Insulin Resistance, Sezin Dagdeviren, Dae Young Jung, Eunjung Lee, Randall H. Friedline, Hye Lim Noh, Jong Hun. Kim, Payal R. Patel, Nicholas Tsitsilianos, Andrew V. Tsitsilianos, Duy A. Tran, George H. Tsougranis, Caitlyn C. Kearns, Cecilia P. Uong, Jung Yeon. Kwon, Werner Muller, Ki Won. Lee, Jason K. Kim Nov 2016

Altered Interleukin-10 Signaling In Skeletal Muscle Regulates Obesity-Mediated Inflammation And Insulin Resistance, Sezin Dagdeviren, Dae Young Jung, Eunjung Lee, Randall H. Friedline, Hye Lim Noh, Jong Hun. Kim, Payal R. Patel, Nicholas Tsitsilianos, Andrew V. Tsitsilianos, Duy A. Tran, George H. Tsougranis, Caitlyn C. Kearns, Cecilia P. Uong, Jung Yeon. Kwon, Werner Muller, Ki Won. Lee, Jason K. Kim

University of Massachusetts Medical School Faculty Publications

Skeletal muscle insulin resistance is a major characteristic of obesity and type 2 diabetes. Although obesity-mediated inflammation is causally associated with insulin resistance, the underlying mechanism is unclear. Here, we examined the effects of chronic obesity in mice with muscle-specific overexpression of interleukin-10 (MIL10). After 16 weeks of a high-fat diet (HFD), MIL10 mice became markedly obese but showed improved insulin action compared to that of wild-type mice, which was largely due to increased glucose metabolism and reduced inflammation in skeletal muscle. Since leptin regulates inflammation, the beneficial effects of interleukin-10 (IL-10) were further examined in leptin-deficient ob/ob mice ...


An Alternative Splicing Program Promotes Adipose Tissue Thermogenesis, Santiago Vernia, Yvonne J. K. Edwards, Myoung Souk Han, Julie Cavanagh-Kyros, Tamera Barrett, Jason K. Kim, Roger J. Davis Sep 2016

An Alternative Splicing Program Promotes Adipose Tissue Thermogenesis, Santiago Vernia, Yvonne J. K. Edwards, Myoung Souk Han, Julie Cavanagh-Kyros, Tamera Barrett, Jason K. Kim, Roger J. Davis

University of Massachusetts Medical School Faculty Publications

Alternative pre-mRNA splicing expands the complexity of the transcriptome and controls isoform-specific gene expression. Whether alternative splicing contributes to metabolic regulation is largely unknown. Here we investigated the contribution of alternative splicing to the development of diet-induced obesity. We found that obesity-induced changes in adipocyte gene expression include alternative pre-mRNA splicing. Bioinformatics analysis associated part of this alternative splicing program with sequence specific NOVA splicing factors. This conclusion was confirmed by studies of mice with NOVA deficiency in adipocytes. Phenotypic analysis of the NOVA-deficient mice demonstrated increased adipose tissue thermogenesis and improved glycemia. We show that NOVA proteins mediate a ...


Drug-Resistant Hiv-1 Protease Regains Functional Dynamics Through Cleavage Site Coevolution, Nevra Ozer, Aysegul Ozen, Celia A. Schiffer, Turkan Haliloglu Feb 2015

Drug-Resistant Hiv-1 Protease Regains Functional Dynamics Through Cleavage Site Coevolution, Nevra Ozer, Aysegul Ozen, Celia A. Schiffer, Turkan Haliloglu

University of Massachusetts Medical School Faculty Publications

Drug resistance is caused by mutations that change the balance of recognition favoring substrate cleavage over inhibitor binding. Here, a structural dynamics perspective of the regained wild-type functioning in mutant HIV-1 proteases with coevolution of the natural substrates is provided. The collective dynamics of mutant structures of the protease bound to p1-p6 and NC-p1 substrates are assessed using the Anisotropic Network Model (ANM). The drug-induced protease mutations perturb the mechanistically crucial hinge axes that involve key sites for substrate binding and dimerization and mainly coordinate the intrinsic dynamics. Yet with substrate coevolution, while the wild-type dynamic behavior is restored in ...


Ethanol Modulation Of Mammalian Bk Channels In Excitable Tissues: Molecular Targets And Their Possible Contribution To Alcohol-Induced Altered Behavior, Alex M. Dopico, Anna N. Bukiya, Gilles E. Martin Dec 2014

Ethanol Modulation Of Mammalian Bk Channels In Excitable Tissues: Molecular Targets And Their Possible Contribution To Alcohol-Induced Altered Behavior, Alex M. Dopico, Anna N. Bukiya, Gilles E. Martin

University of Massachusetts Medical School Faculty Publications

In most tissues, the function of Ca(2+)- and voltage-gated K(+) (BK) channels is modified in response to ethanol concentrations reached in human blood during alcohol intoxication. In general, modification of BK current from ethanol-naive preparations in response to brief ethanol exposure results from changes in channel open probability without modification of unitary conductance or change in BK protein levels in the membrane. Protracted and/or repeated ethanol exposure, however, may evoke changes in BK expression. The final ethanol effect on BK open probability leading to either BK current potentiation or BK current reduction is determined by an orchestration of ...


Ifitm3 Restricts Influenza A Virus Entry By Blocking The Formation Of Fusion Pores Following Virus-Endosome Hemifusion, Tanay M. Desai, Mariana Marin, Christopher R. Chin, George Savidis, Abraham L. Brass, Gregory B. Melikyan Apr 2014

Ifitm3 Restricts Influenza A Virus Entry By Blocking The Formation Of Fusion Pores Following Virus-Endosome Hemifusion, Tanay M. Desai, Mariana Marin, Christopher R. Chin, George Savidis, Abraham L. Brass, Gregory B. Melikyan

University of Massachusetts Medical School Faculty Publications

Interferon-induced transmembrane proteins (IFITMs) inhibit infection of diverse enveloped viruses, including the influenza A virus (IAV) which is thought to enter from late endosomes. Recent evidence suggests that IFITMs block virus hemifusion (lipid mixing in the absence of viral content release) by altering the properties of cell membranes. Consistent with this mechanism, excess cholesterol in late endosomes of IFITM-expressing cells has been reported to inhibit IAV entry. Here, we examined IAV restriction by IFITM3 protein using direct virus-cell fusion assay and single virus imaging in live cells. IFITM3 over-expression did not inhibit lipid mixing, but abrogated the release of viral ...


The Dna Damage And The Dna Replication Checkpoints Converge At The Mbf Transcription Factor, Tsvetomira Ivanova, Isabel Alves-Rodrigues, Blanca Gomez-Escoda, Chaitali Dutta, James A. Decaprio, Nicholas R. Rhind, Elena Hidalgo, Jose Ayte Nov 2013

The Dna Damage And The Dna Replication Checkpoints Converge At The Mbf Transcription Factor, Tsvetomira Ivanova, Isabel Alves-Rodrigues, Blanca Gomez-Escoda, Chaitali Dutta, James A. Decaprio, Nicholas R. Rhind, Elena Hidalgo, Jose Ayte

University of Massachusetts Medical School Faculty Publications

In fission yeast cells, Cds1 is the effector kinase of the DNA replication checkpoint. We previously showed that when the DNA replication checkpoint is activated, the repressor Yox1 is phosphorylated and inactivated by Cds1, resulting in activation of MluI-binding factor (MBF)-dependent transcription. This is essential to reinitiate DNA synthesis and for correct G1-to-S transition. Here we show that Cdc10, which is an essential part of the MBF core, is the target of the DNA damage checkpoint. When fission yeast cells are treated with DNA-damaging agents, Chk1 is activated and phosphorylates Cdc10 at its carboxy-terminal domain. This modification is responsible ...


Rage Is A Nucleic Acid Receptor That Promotes Inflammatory Responses To Dna, Cherilyn M. Sirois, Tengchuan Jin, Allison L. Miller, Damien Bertheloot, Hirotaka Nakamura, Gabor Horvath, Abubakar Mian, Jiansheng Jiang, Jacob Schrum, Lukas Bossaller, Karin Pelka, Natalio Garbi, Yambasu Brewah, Jane Tian, Chewshun Chang, Partha S. Chowdhury, Gary P. Sims, Roland Kolbeck, Anthony J. Coyle, Alison A. Humbles, T. Sam Xiao, Eicke Latz Oct 2013

Rage Is A Nucleic Acid Receptor That Promotes Inflammatory Responses To Dna, Cherilyn M. Sirois, Tengchuan Jin, Allison L. Miller, Damien Bertheloot, Hirotaka Nakamura, Gabor Horvath, Abubakar Mian, Jiansheng Jiang, Jacob Schrum, Lukas Bossaller, Karin Pelka, Natalio Garbi, Yambasu Brewah, Jane Tian, Chewshun Chang, Partha S. Chowdhury, Gary P. Sims, Roland Kolbeck, Anthony J. Coyle, Alison A. Humbles, T. Sam Xiao, Eicke Latz

University of Massachusetts Medical School Faculty Publications

Recognition of DNA and RNA molecules derived from pathogens or self-antigen is one way the mammalian immune system senses infection and tissue damage. Activation of immune signaling receptors by nucleic acids is controlled by limiting the access of DNA and RNA to intracellular receptors, but the mechanisms by which endosome-resident receptors encounter nucleic acids from the extracellular space are largely undefined. In this study, we show that the receptor for advanced glycation end-products (RAGE) promoted DNA uptake into endosomes and lowered the immune recognition threshold for the activation of Toll-like receptor 9, the principal DNA-recognizing transmembrane signaling receptor. Structural analysis ...


Phosphorylation Of Centromeric Histone H3 Variant Regulates Chromosome Segregation In S. Cerevisiae, Lars Boeckmann, Yoshimitsu Takahashi, Wei-Chun Au, Prashant K. Mishra, John S. Choy, Anthony R. Dawson, May Y. Szeto, Timothy J. Waybright, Christopher Heger, Christopher Mcandrew, Paul K. Goldsmith, Timothy D. Veenstra, Richard E. Baker, Munira A. Basrai Jun 2013

Phosphorylation Of Centromeric Histone H3 Variant Regulates Chromosome Segregation In S. Cerevisiae, Lars Boeckmann, Yoshimitsu Takahashi, Wei-Chun Au, Prashant K. Mishra, John S. Choy, Anthony R. Dawson, May Y. Szeto, Timothy J. Waybright, Christopher Heger, Christopher Mcandrew, Paul K. Goldsmith, Timothy D. Veenstra, Richard E. Baker, Munira A. Basrai

University of Massachusetts Medical School Faculty Publications

The centromeric histone H3 variant (CenH3) is essential for chromosome segregation in eukaryotes. We have identified posttranslational modifications of S. cerevisiae CenH3, Cse4. Functional characterization of cse4 phosphorylation mutants showed growth and chromosome segregation defects when combined with kinetochore mutants okp1 and ame1. Using a phosphoserine-specific antibody we showed that the association of phosphorylated Cse4 with centromeres is increased in response to defective microtubule attachment or reduced cohesion. We determined that evolutionarily conserved Ipl1/Aurora B contributes to phosphorylation of Cse4, as levels of phosphorylated Cse4 were reduced at centromeres in ipl1 strains in vivo and in vitro assays showed ...


The Cellular And Molecular Basis Of Bitter Tastant-Induced Bronchodilation, Cheng-Hai Zhang, Lawrence M. Lifshitz, Karl Uy, Mitsuo Ikebe, Kevin E. Fogarty, Ronghua Zhuge Mar 2013

The Cellular And Molecular Basis Of Bitter Tastant-Induced Bronchodilation, Cheng-Hai Zhang, Lawrence M. Lifshitz, Karl Uy, Mitsuo Ikebe, Kevin E. Fogarty, Ronghua Zhuge

University of Massachusetts Medical School Faculty Publications

Bronchodilators are a standard medicine for treating airway obstructive diseases, and beta2 adrenergic receptor agonists have been the most commonly used bronchodilators since their discovery. Strikingly, activation of G-protein-coupled bitter taste receptors (TAS2Rs) in airway smooth muscle (ASM) causes a stronger bronchodilation in vitro and in vivo than beta2 agonists, implying that new and better bronchodilators could be developed. A critical step towards realizing this potential is to understand the mechanisms underlying this bronchodilation, which remain ill-defined. An influential hypothesis argues that bitter tastants generate localized Ca(2+) signals, as revealed in cultured ASM cells, to activate large-conductance Ca(2 ...


Uv Damage Regulates Alternative Polyadenylation Of The Rpb2 Gene In Yeast, Lijian Yu, Michael R. Volkert Mar 2013

Uv Damage Regulates Alternative Polyadenylation Of The Rpb2 Gene In Yeast, Lijian Yu, Michael R. Volkert

University of Massachusetts Medical School Faculty Publications

Alternative polyadenylation (APA) is conserved in all eukaryotic cells. Selective use of polyadenylation sites appears to be a highly regulated process and contributes to human pathogenesis. In this article we report that the yeast RPB2 gene is alternatively polyadenylated, producing two mRNAs with different lengths of 3'UTR. In normally growing wild-type cells, polyadenylation preferentially uses the promoter-proximal poly(A) site. After UV damage transcription of RPB2 is initially inhibited. As transcription recovers, the promoter-distal poly(A) site is preferentially used instead, producing more of a longer form of RPB2 mRNA. We show that the relative increase in the long ...