Regulation of Airway Mucin Gene Expression by Epigenetic Mechanism

Summary

Principal Investigator: Reen Wu
Abstract: DESCRIPTION (provided by applicant): Mucins are major contributors to the visco-elastic properties of mucus secretion, which plays an important role in the mucociliary clearance in conducting airways. Aberrant mucus accumulation due to mucin overproduction is one of major clinical symptoms associated with various lung diseases, such as asthma, cystic fibrosis, bronchitis, chronic obstructive pulmonary diseases, etc. Significant progress has been made in the cloning, expression characterization, and the identification of mediators and regulatory pathways involved in airway mucin synthesis and secretion. However, the cell type-specificity and the persistent nature of aberrant mucin secretion in various lung patients, even following recovery, are still unclear. We hypothesize that the persistent phenomenon is related to epigenetic modification on mucin gene in addition to other modifications, such as airway remodeling and elevated presence of inflammatory cytokines in airways. Preliminary studies have shown the presence of CpG islands in the upstream promoter region of human MUC5AC (at -4,396 bp - 4,541bp), which is not present in the mouse orthologue. The level of MUC5AC expression in various human airway cell lines and primary normal bronchial epithelial (NHBE) cells are affected by the methylation status of the CpG islands. Furthermore, we showed both all-trans-retinoic acid and smoke are able to alter the methylation status of MUC5AC CpG islands and that this status is inversely related MUC5AC gene expression. Based on these results, we hypothesize that epigenetic changes, especially changes in DNA methylation status, is one of the major mechanisms involved in the persistence of mucin gene expression, especially MUC5AC. To further test this hypothesis, three specific aims are proposed. The first aim is to determine if differential MUC5AC expression in various cell lines and primary NHBE cells is regulated by epigenetic mechanisms, including changes in CpG island DNA methylation status and chromatin structure. The second aim is to address whether retinoic acid induced MUC5AC expression in cell lines, as well as in primary cells, is associated with epigenetic mechanisms that include alterations in DNA methylation status of CpG islands, and alterations in chromatin structure. The third aim is to determine if smoke-induced persistence of MUC5AC expression is associated with alterations in the DNA methylation status of CpG islands and/or chromatin structure in human subjects. To determine CpG island DNA methylation status, both bisulfite sequencing and quantitative PCR with methylated and non- methylated sequences-specific primers will be used. Chromatin immunoprecipitation (ChIP) approaches with anti-methylated deoxy-cytosine and various anti-modified histone antibodies will be used to assess DNA methylation profiles and chromatin structure of MUC5AC. Using siRNA as well as overexpression approaches, the effects of DNA methyltransferases (DNMTs) on CpG island methylation status and MUC5AC expression will be established. PUBLIC HEALTH RELEVANCE: Aberrant airway mucin expression is a major clinical problem associated with various lung diseases;specifically, diseases airways are associated with a persistent elevation of mucin production. The nature of this persistence is unresolved. We hypothesize that epigenetic changes, especially changes in DNA methylation status and chromatin structure, are involved in the persistent elevation of MUC5AC expression in human airway cells from diseased states. We plan to identify unique molecular signatures that contribute to the regulation of MUC5AC gene expression at the epigenetic level. Understanding the unique aspects of epigenetic mechanisms involved in airway mucin gene expression will lead to a better understanding of aberrant mucin production in the airway, as well as to the development of novel therapeutic approaches to treating airway diseases.
Funding Period: 2010-04-01 - 2015-03-31
more information: NIH RePORT

Top Publications

  1. pmc 2,3,7,8-Tetrachlorodibenzo-p-dioxin-induced MUC5AC expression: aryl hydrocarbon receptor-independent/EGFR/ERK/p38-dependent SP1-based transcription
    Yong C Lee
    Center for Comparative Respiratory Biology and Medicine, University of California at Davis, 95616, USA
    Am J Respir Cell Mol Biol 45:270-6. 2011
  2. pmc Differential effects of simvastatin on IL-13-induced cytokine gene expression in primary mouse tracheal epithelial cells
    Amir A Zeki
    U C Davis, School of Medicine, U C Davis Medical Center, Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Center for Comparative Respiratory Biology and Medicine, Davis, CA, USA
    Respir Res 13:38. 2012
  3. pmc Combination erlotinib-cisplatin and Atg3-mediated autophagy in erlotinib resistant lung cancer
    Jasmine G Lee
    Department of Internal Medicine, Division of Respiratory Medicine, University of California Davis, United States of America
    PLoS ONE 7:e48532. 2012
  4. pmc Characterization of a novel long noncoding RNA, SCAL1, induced by cigarette smoke and elevated in lung cancer cell lines
    Philip Thai
    Center for Comparative Respiratory Biology and Medicine, Genome and Biomedical Science Facility, and Division of Pulmonary and Critical Care Medicine, School of Medicine, University of California at Davis, Davis, CA 95616, USA
    Am J Respir Cell Mol Biol 49:204-11. 2013
  5. pmc IL-17A and Th17 cells in lung inflammation: an update on the role of Th17 cell differentiation and IL-17R signaling in host defense against infection
    Hsing Chuan Tsai
    Center for Comparative Respiratory Biology and Medicine, University of California, Davis, CA 95616, USA
    Clin Dev Immunol 2013:267971. 2013
  6. pmc Cholera toxin directly enhances IL-17A production from human CD4+ T cells
    Hsing Chuan Tsai
    Center for Comparative Respiratory Biology and Medicine, University of California, Davis, Davis, CA 95616
    J Immunol 191:4095-102. 2013

Detail Information

Publications7

  1. pmc 2,3,7,8-Tetrachlorodibenzo-p-dioxin-induced MUC5AC expression: aryl hydrocarbon receptor-independent/EGFR/ERK/p38-dependent SP1-based transcription
    Yong C Lee
    Center for Comparative Respiratory Biology and Medicine, University of California at Davis, 95616, USA
    Am J Respir Cell Mol Biol 45:270-6. 2011
    ..These results lead to the conclusion that TCDD induced MUC5AC expression through a noncanonical aryl hydrocarbon receptor-independent, EGFR/ERK/p38-mediated signaling pathway-mediated/Sp1-based transcriptional mechanism...
  2. pmc Differential effects of simvastatin on IL-13-induced cytokine gene expression in primary mouse tracheal epithelial cells
    Amir A Zeki
    U C Davis, School of Medicine, U C Davis Medical Center, Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Center for Comparative Respiratory Biology and Medicine, Davis, CA, USA
    Respir Res 13:38. 2012
    ..Using an allergic mouse model of asthma, we previously demonstrated a benefit of statins in reducing peribronchiolar eosinophilic inflammation, airway hyperreactivity, goblet cell hyperplasia, and lung IL-4 and IL-13 production...
  3. pmc Combination erlotinib-cisplatin and Atg3-mediated autophagy in erlotinib resistant lung cancer
    Jasmine G Lee
    Department of Internal Medicine, Division of Respiratory Medicine, University of California Davis, United States of America
    PLoS ONE 7:e48532. 2012
    ..Also, we demonstrate that combination erlotinib-cisplatin is an effective treatment against erlotinib resistant cancer by targeting (down-regulating) Atg3 mediated autophagy and induction of apoptotic cell death...
  4. pmc Characterization of a novel long noncoding RNA, SCAL1, induced by cigarette smoke and elevated in lung cancer cell lines
    Philip Thai
    Center for Comparative Respiratory Biology and Medicine, Genome and Biomedical Science Facility, and Division of Pulmonary and Critical Care Medicine, School of Medicine, University of California at Davis, Davis, CA 95616, USA
    Am J Respir Cell Mol Biol 49:204-11. 2013
    ..Altogether, these results identify a novel and intriguing new noncoding RNA that may act downstream of NRF2 to regulate gene expression and mediate oxidative stress protection in airway epithelial cells. ..
  5. pmc IL-17A and Th17 cells in lung inflammation: an update on the role of Th17 cell differentiation and IL-17R signaling in host defense against infection
    Hsing Chuan Tsai
    Center for Comparative Respiratory Biology and Medicine, University of California, Davis, CA 95616, USA
    Clin Dev Immunol 2013:267971. 2013
    ..In this review, we summarize the recent advances in unraveling the mechanism behind Th17 cell differentiation, IL-17A/IL-17R signaling, and also the importance of IL-17A in pulmonary infection. ..
  6. pmc Cholera toxin directly enhances IL-17A production from human CD4+ T cells
    Hsing Chuan Tsai
    Center for Comparative Respiratory Biology and Medicine, University of California, Davis, Davis, CA 95616
    J Immunol 191:4095-102. 2013
    ..This study shows that CT has the capacity to directly shape Th17 responses in the absence of APCs. Our findings highlight the potentials of bacterial toxins in the regulation of human Th17 responses. ..

Research Grants30

  1. MECHANISMS IN THE REGULATION OF SP-A GENE EXPRESSION
    Carole R Mendelson; Fiscal Year: 2013
    ....
  2. Re-expression of Aberrantly Silenced Genes Induced by Polyamine Analogues
    Robert A Casero; Fiscal Year: 2013
    ..abstract_text> ..
  3. Transcriptional Regulation by Angiotensin II in Vascular Smooth Muscle Cells
    Rama Natarajan; Fiscal Year: 2013
    ..The results can increase our understanding of Ang II actions, and identify new targets that might be developed as clinical therapies for CVDs such as hypertension and atherosclerosis. ..
  4. Jules Stein Eye Institute Core Grant for Vision Research
    Wayne L Hubbell; Fiscal Year: 2013
    ..Support in the form of the Core grant is requested to maintain these Modules through instrument service contracts, and to provide necessary personnel support to assist and train users and provide routine maintenance. ..
  5. MicroRNAs in the Progression and Metastisis of Prostate Cancer
    Rajvir Dahiya; Fiscal Year: 2013
    ..In the future, these results may provide better strategies for the management of prostate cancer. ..
  6. Functional Analysis of the Embryonic Epigenome in a Non-rodent Model
    Mark E Westhusin; Fiscal Year: 2013
    ....
  7. LIAI Epitope Validation Center: Characterization of Allergen specific T Cells
    ALESSANDRO D SETTE; Fiscal Year: 2013
    ..abstract_text> ..
  8. CPG METHYLATION AND MUTATION
    Gerd P Pfeifer; Fiscal Year: 2013
    ..In parallel, we will study molecular pathways involving the Polycomb repression complex that might operate during tumor progression to promote hypermethylation of CpG islands in malignant tissue. ..