A cross-kingdom conserved ER-phagy receptor maintains endoplasmic reticulum homeostasis during stress

ABSTRACT: We have identified a potential selective autophagy receptor protein in Arabidopsis thaliana, C53/AT5G06830/ERP1, that is recruited to ER upon ER-stress activation and induces autophagosome formation. By affinity proteomics IP/MS with ATG8A and E, we identified this new ER-phagy receptor, which is also conserved in metazoans. With biophysical characterization, we revealed its unprecedent binding mode to ATG8 (sAIM). C53 senses proteotoxic stress in the ER lumen by forming a tripartite receptor complex with the ER-associated ufmylation ligase UFL1 and its membrane adaptor DDRGK1. However, its cargo targeted for degradation is still elusive. Initial quantitative proteomics analyses (TMT) of wild type and Atc53 mutant lines revealed that Atc53 mediates degradation of ER resident proteins as well as proteins passaging the ER to the cell wall, apoplast, and lipid droplets.

INSTRUMENT(S):

ORGANISM(S): Arabidopsis Thaliana (mouse-ear Cress)

TISSUE(S): Root, Leaf

SUBMITTER: Richard Imre  

LAB HEAD: Yasin Dagdas

PROVIDER: PXD019988 | Pride | 2021-09-09

REPOSITORIES: Pride