研究發現小分子可促進溶酶體降解
作者:
小柯機器人發布時間:2019/7/30 16:21:02
2019年7月25日出版的《細胞》雜誌發表了來自麻省理工學院和哈佛大學的Anna Greka小組的研究成果。他們發現了小分子以TMED9為靶點,可以促進溶酶體降解,逆轉蛋白病。
研究團隊證明MKD是一種毒性蛋白病。細胞內MUC1-fs的積累激活了ATF6未摺疊蛋白反應(UPR)分支。該課題組人員鑑定出一種小分子BRD4780,該分子可以清除患者細胞、基因敲入小鼠腎臟和患者腎臟器官內的MUC1-fs。MUC1-fs被困在含有運貨受體TMED9的早期分泌途徑囊泡內。BRD4780與TMED9結合,釋放MUC1-fs,並將其重新轉運,使其被溶酶體降解(TMED9缺失表型模擬效果)。他們的發現表明BRD4780有可能成為治療MKD及其它毒性蛋白疾病的先導。總的來說,研究團隊闡明了錯誤摺疊蛋白質被運貨受體捕獲的新機制,以及將其釋放和順行運輸到溶酶體的策略。
據介紹,細胞內錯誤摺疊蛋白的積累可導致毒性蛋白病變,這類疾病無法做到靶向治療。Mucin 1腎病(MKD)是由MUC1基因(MUC1-fs)的移碼突變引起的。
附:英文原文
Title: Small Molecule Targets TMED9 and Promotes Lysosomal Degradation to Reverse Proteinopathy
Author: Moran Dvela-Levitt, Maria Kost-Alimova, Maheswarareddy Emani, Todd R. Golub, Eric S. Lander, Anna Greka
Issue&Volume: Volume 178 Issue 3
Abstract: Intracellular accumulation of misfolded proteins causes toxic proteinopathies, diseases without targeted therapies. Mucin 1 kidney disease (MKD) results from a frameshift mutation in the MUC1 gene (MUC1-fs). Here, we show that MKD is a toxic proteinopathy. Intracellular MUC1-fs accumulation activated the ATF6 unfolded protein response (UPR) branch. We identified BRD4780, a small molecule that clears MUC1-fs from patient cells, from kidneys of knockin mice and from patient kidney organoids. MUC1-fs is trapped in TMED9 cargo receptor-containing vesicles of the early secretory pathway. BRD4780 binds TMED9, releases MUC1-fs, and re-routes it for lysosomal degradation, an effect phenocopied by TMED9 deletion. Our findings reveal BRD4780 as a promising lead for the treatment of MKD and other toxic proteinopathies. Generally, we elucidate a novel mechanism for the entrapment of misfolded proteins by cargo receptors and a strategy for their release and anterograde trafficking to the lysosome.
DOI: DOI:https://doi.org/10.1016/j.cell.2019.07.002
Source: https://www.cell.com/cell/fulltext/S0092-8674(19)30741-X
Cell:《細胞》,創刊於1974年。隸屬於細胞出版社,最新IF:36.216