Jang, Mi Park, Byoung Chul Lee, Ah Young Na, Kyeong Sook Kang, Sunghyun Bae, Kwang-Hee Myung, Pyung Keun Chung, Bong Chul Cho, Sayeon Lee, Do Hee Park, Sung Goo 2024-01-21T00:05:00Z 2024-01-21T00:05:00Z 2021-09-02 2007-11-16 0006-291X https://pubs.kist.re.kr/handle/201004/133975 Caspase-3 and caspase-7 are structurally closely related and demonstrate overlapping substrate specificity. However, during apoptosis, they are differentially regulated and show distinct subcellular localizations, implying the presence of specific substrates. In this study, to identify caspase-7 substrates, we treated the lysates derived from caspase-3-cleficient MCF-7 cells with purified caspase-7 and analyzed decreased proteins by 2-DE. Intriguingly, several proteasome subunits such as alpha 2 alpha 6, and Rpt1 are degraded by caspase-7 during apoptosis in vitro and in vivo. Caspase-7 mediated cleavage of proteasome subunits results in the reduction of proteasome activity and thereby increases the accumulation of ubiquitinated proteins in cells. These findings suggest that caspase-7 facilitates the execution of apoptosis through down-regulation of the 26S proteasome, which regulates the turnover of proteins involved in the apoptotic process. (C) 2007 Elsevier Inc. All rights reserved. English ACADEMIC PRESS INC ELSEVIER SCIENCE PROGRAMMED CELL-DEATH GEL-ELECTROPHORESIS CANCER-CELLS ACTIVATION IDENTIFICATION PROTEOLYSIS UBIQUITIN PROTEINS Caspase-7 mediated cleavage of proteasome subunits during apoptosis Article 10.1016/j.bbrc.2007.08.183 1 BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, v.363, no.2, pp.388 - 394 BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS 363 2 388 394 scie scopus 000250121500025 2-s2.0-34748884951 Biochemistry & Molecular Biology Biophysics Biochemistry & Molecular Biology Biophysics Article PROGRAMMED CELL-DEATH GEL-ELECTROPHORESIS CANCER-CELLS ACTIVATION IDENTIFICATION PROTEOLYSIS UBIQUITIN PROTEINS apoptosis caspase-7 2-DE proteasome ubiquitination