Endoplasmic reticulum stress-induced mRNA splicing permits synthesis of transcription factor Hac1p/Ern4p that activates the unfolded protein response.

ABSTRACT: An intracellular signaling from the endoplasmic reticulum (ER) to the nucleus, called the unfolded protein response (UPR), is activated when unfolded proteins are accumulated in the ER under a variety of stress conditions ("ER stress"). We and others recently identified Hac1p/Ern4p as a transcription factor responsible for the UPR in Saccharomyces cerevisiae. It was further reported that Hac1p (238 aa) is detected only in ER-stressed cells, and its expression is mediated by unconventional splicing of HAC1 precursor mRNA. The splicing replaces the C-terminal portion of Hac1p; it was proposed that precursor mRNA is also translated but the putative product of 230 aa is rapidly degraded by the ubiquitin-proteasome pathway. We have identified and characterized the same regulated splicing and co

SUBMITTER: Kawahara T 

PROVIDER: S-EPMC25627 | biostudies-literature | 1997 Oct

REPOSITORIES: biostudies-literature