磷酸化調控的eIF3d翻譯開關介導了細胞對代謝壓力的適應
作者:
小柯機器人發布時間:2020/11/14 23:44:34
美國哈佛醫學院Amy S. Y. Lee課題組近日取得一項新成果。經過不懈努力,他們的最新發現磷酸化調控的eIF3d翻譯開關介導了細胞適應代謝壓力。2020年11月13日,國際學術期刊《科學》發表了這一成果
在本研究中,研究人員發現非典型的5'帽結合蛋白eIF3d響應人細胞中的代謝應激而被激活。激活需要降低eIF3d 5』帽結合口袋附近CK2介導的磷酸化。eIF3d調控的基因程序富含調節體內葡萄糖穩態的重要因子,例如哺乳動物體內雷帕黴素(mTOR)通路的靶蛋白。eIF3d介導的翻譯對慢性葡萄糖匱乏時細胞的存活至關重要。因此,這種翻譯重編程機制調節細胞對代謝應激的反應。
據介紹,全面關閉蛋白質合成的是細胞應激的保守反應。這種普遍現象受每種壓力特異基因程序的調節。儘管驅動一般蛋白質合成抑制的機制已得到了廣泛研究,但人們對細胞如何選擇性編程翻譯機制以實現選擇性基因表達仍知之甚少。
附:英文原文
Title: A phosphorylation-regulated eIF3d translation switch mediates cellular adaptation to metabolic stress
Author: Adam M. Lamper, Rebecca H. Fleming, Kayla M. Ladd, Amy S. Y. Lee
Issue&Volume: 2020/11/13
Abstract: Shutoff of global protein synthesis is a conserved response to cellular stresses. This general phenomenon is accompanied by the induction of distinct gene programs tailored to each stress. Although the mechanisms driving repression of general protein synthesis are well characterized, how cells reprogram the translation machinery for selective gene expression remains poorly understood. Here, we found that the noncanonical 5′ cap-binding protein eIF3d was activated in response to metabolic stress in human cells. Activation required reduced CK2-mediated phosphorylation near the eIF3d cap-binding pocket. eIF3d controls a gene program enriched in factors important for glucose homeostasis, including members of the mammalian target of rapamycin (mTOR) pathway. eIF3d-directed translation adaptation was essential for cell survival during chronic glucose deprivation. Thus, this mechanism of translation reprogramming regulates the cellular response to metabolic stress.
DOI: 10.1126/science.abb0993
Source: https://science.sciencemag.org/content/370/6518/853
Science:《科學》,創刊於1880年。隸屬於美國科學促進會,最新IF:41.037