Sec61β maintains cytoplasmic proteostasis via ARIH1-mediated translational repression upon ER stress.

ABSTRACT: Disrupted proteostasis causes various degenerative diseases, and organelle homeostasis is therefore maintained by elaborate mechanisms. Endoplasmic reticulum (ER) stress-induced preemptive quality control (ERpQC) counteracts stress by reducing ER load through inhibiting the translocation of newly synthesized proteins into the ER for their rapid degradation in the cytoplasm. Here, we show that Sec61β, a translocon component, prevents the overproduction of ERpQC substrates, allowing for their efficient degradation by the proteasome. Sec61β inhibits the binding of translation initiation factor eIF4E to the mRNA 5' cap structure by recruiting E3 ligase ARIH1 and eIF4E-homologous protein 4EHP, resulting in selective translational repression of ERpQC substrates. Sec61β deficiency causes overprod

SUBMITTER: Kadowaki H 

PROVIDER: S-EPMC12936171 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature