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PBRM1 Regulates Stress Response in Epithelial Cells.

ABSTRACT: Polybromo1 (PBRM1) is a chromatin remodeler subunit highly mutated in cancer, particularly clear cell renal carcinoma. PBRM1 is a member of the SWI/SNF subcomplex, PBAF (PBRM1-Brg1/Brm-associated factors), and is characterized by six tandem bromodomains. Here we establish a role for PBRM1 in epithelial cell maintenance through the expression of genes involved in cell adhesion, metabolism, stress response, and apoptosis. In support of a general role for PBRM1 in stress response and apoptosis, we observe that loss of PBRM1 results in an increase in reactive oxygen species generation and a decrease in cellular viability under stress conditions. We find that loss of PBRM1 promotes cell growth under favorable conditions but is required for cell survival under conditions of cellular stress.

SUBMITTER: Porter EG

PROVIDER: S-EPMC6514269 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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PBRM1 Regulates Stress Response in Epithelial Cells.

Porter Elizabeth G EG Dhiman Alisha A Chowdhury Basudev B Carter Benjamin C BC Lin Hang H Stewart Jane C JC Kazemian Majid M Wendt Michael K MK Dykhuizen Emily C EC

iScience 20190426

Polybromo1 (PBRM1) is a chromatin remodeler subunit highly mutated in cancer, particularly clear cell renal carcinoma. PBRM1 is a member of the SWI/SNF subcomplex, PBAF (PBRM1-Brg1/Brm-associated factors), and is characterized by six tandem bromodomains. Here we establish a role for PBRM1 in epithelial cell maintenance through the expression of genes involved in cell adhesion, metabolism, stress response, and apoptosis. In support of a general role for PBRM1 in stress response and apoptosis, we ...[more]

PMID: 31077944

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