A COPⅡ subunit interacting with ER-phagy receptor: a new potential avenue to maintaining neuronal homeostasis

• 作者: Haoliang Hu Honglu Jiang Mingzhu Tang Shifang Huang Yuting Li
• 来源期刊: 生物化学与生物物理学报（英文版）
• 年，卷（期）: 2020,（6）
• 页码范围: 698-700
• 页数: 3页
• 语种: 英文
• DOI: 10.1093/abbs/gmaa031

摘要

Endoplasmic reticulum (ER)-associated degradation (ERAD) plays an essential role in protein quality control in the ER.It acts through recognizing misfolded or unassembled proteins and retrotranslocaring them across the ER membrane into the cytosol for degradation.ER-phagy,which is an ERAD pathway,also controls the quality and abundance of proteins and organelles by activating ER-resident receptors.ER membrane is the important site of initiation for phagophores (crescent-shaped membranes that form and mature into autophagosomes);however,specific sites that are restricted on ER during ER-phagy remain to be identified.Recently,Cui et al.[1] found that a COPⅡ coat subunit,Lst1/SEC24C-Sec23,plays an unconventional role in targeting ER domains for degradation of the ER-phagy receptor,which makes them essential to ER-phagy.In yeast,the COPII-cargo adaptor complex Lst1-Sec23 co-localizes with up-regulated ER-phagy receptor Atg40 (FAM134B in mammals) to sort ER domains into autophagosomes during ER-phagy,eventually leading to the reduction of protein aggregation in ER.In mammals,the formation of Lst1/SEC24C-Sec23 is required for the degradation of two mammalian ER-phagy receptors,FAM134B and RTN3.They concluded that the COPⅡ subunit Lst1/SEC24C-Sec23 functions with ER-phagy receptors to package ER domains for degradation,thereby reducing protein aggregation and preserving cellular health [1].