ADP/ATP轉位酶可促進線粒體自噬
作者:
小柯機器人發布時間:2019/10/17 14:10:48
近日,美國賓州大學Zoltan Arany及其研究小組發現ADP/ATP轉位酶促進線粒體自噬但不依賴於其酶活。相關論文2019年10月16日在線發表在《自然》雜誌上。
研究人員設計了一個多維度的CRISPR / Cas9遺傳篩選,使用了多個線粒體報告系統和促線粒體自噬觸發器,並揭示了Parkin蛋白依賴性線粒體自噬的許多新成分。出乎意料的是,研究人員確定了多種細胞類型線粒體自噬所必需的腺嘌呤核苷酸轉運蛋白(ANT)複合體。ANT介導的ADP/ATP交換的藥理抑制作用促進了線粒體自噬,而ANT的遺傳敲除卻自相矛盾地抑制了線粒體吞噬。重要的是,ANT不需要其核苷酸的轉位酶催化活性來促進線粒體自噬。取而代之的是,需要ANT複合物來抑制前序列轉位酶TIM23,從而響應生物能崩潰,並導致PINK1穩定。ANT通過與TIM44相互作用而間接調節TIM23,已知其調控通過TIM232的多肽導入。
缺少ANT1的小鼠表現出線粒體自噬減少和隨之而來的線粒體異常積累。人類ANT1的致病性突變消除了與TIM44和TIM23的結合併抑制線粒體自噬。這些數據一起確定了ANT作為健康和疾病中線粒體自噬的基本介導者的新穎和關鍵功能。
據了解,線粒體穩態主要取決於線粒體自噬,即線粒體的程序性降解。已知參與線粒體自噬的蛋白質仍然很少。
附:英文原文
Title: The ADP/ATP translocase drives mitophagy independent of nucleotide exchange
Author: Atsushi Hoshino, Wei-jia Wang, Shogo Wada, Chris McDermott-Roe, Chantell S. Evans, Bridget Gosis, Michael P. Morley, Komal S. Rathi, Jian Li, Kristina Li, Steven Yang, Meagen J. McMannus, Caitlyn Bowman, Prasanth Potluri, Michael Levin, Scott Damrauer, Douglas C. Wallace, Erika L. F. Holzbaur, Zoltan Arany
Issue&Volume: 2019-10-16
Abstract:
Mitochondrial homeostasis vitally depends on mitophagy, the programmed degradation of mitochondria. The roster of proteins known to participate in mitophagy remains small. We devised here a multidimensional CRISPR/Cas9 genetic screen, using multiple mitophagy reporter systems and pro-mitophagy triggers, and uncover numerous new components of Parkin-dependent mitophagy1. Unexpectedly, we identify the adenine nucleotide translocator (ANT) complex as required for mitophagy in multiple cell types. While pharmacological inhibition of ANT-mediated ADP/ATP exchange promotes mitophagy, genetic ablation of ANT paradoxically suppresses mitophagy. Importantly, ANT promotes mitophagy independently of its nucleotide translocase catalytic activity. Instead, the ANT complex is required for inhibition of the presequence translocase TIM23, leading to PINK1 stabilization, in response to bioenergetic collapse. ANT modulates TIM23 indirectly via interaction with TIM44, known to regulate peptide import through TIM232. Mice lacking ANT1 reveal blunted mitophagy and consequent profound accumulation of aberrant mitochondria. Disease-causing human mutations in ANT1 abrogate binding to TIM44 and TIM23 and inhibit mitophagy. Together, these data identify a novel and essential function for ANT as a fundamental mediator of mitophagy in health and disease.
DOI: 10.1038/s41586-019-1667-4
Source:https://www.nature.com/articles/s41586-019-1667-4