Immediate early gene-X1 interferes with 26 S proteasome activity by attenuating expression of the 19 S proteasomal components S5a/Rpn10 and S1/Rpn2.

ABSTRACT: The stress response gene IEX-1 (immediate early gene-X-1) is involved in the regulation of cell growth and cellular viability. To some extent, these effects include an interference with the proteasomal turnover of certain regulatory proteins. Here, we show that IEX-1 directly attenuates the activity and formation of the 26 S proteasome in HEK-293 cells (human embryonic kidney cells). We further demonstrate that IEX-1 reduces the overall expression levels of certain protein components of the 19 S proteasomal subunit such as S5a/Rpn10 and S1/Rpn2, whereas the expression of other proteasomal proteins was less or not affected. In contrast with direct apoptotic stimuli, such as the anti-cancer drug etoposide, leading to caspase-dependent degradation of S1 and S5a, the effect of IEX-1 is indepen

SUBMITTER: Arlt A 

PROVIDER: S-EPMC1798431 | biostudies-literature | 2007 Mar

REPOSITORIES: biostudies-literature