Science：科學家發現鈣通道“線粒體蛋白EMRE”

       美國馬薩諸塞州總醫院和哈佛醫學院等機構組成的研究組zui近發現鈣運輸鏈中的zui后一環：一個叫做EMRE的線粒體蛋白。這一研究發現不僅有望更深入地闡明線粒體的運作機制，還為調查鈣運輸對于疾病的貢獻——其中包括在生命的頭幾個月內導致死亡的罕見線粒體疾病開啟了大門。相關文章在《Science》雜志上發表。

原文摘要：

EMRE is an Essential Component of the Mitochondrial Calcium Uniporter Complex

Yasemin Sancak, Andrew L. Markhard, Toshi Kitami, Erika Kovács-Bogdán, Kimberli J. Kamer,Namrata D. Udeshi, Steven A. Carr, Dipayan Chaudhuri, David E. Clapham, Andrew A. Li, Sarah E. Calvo,Olga Goldberger, Vamsi K. Mootha

The mitochondrial uniporter is a highly selective calcium channel in the organelle’s inner membrane. Its molecular components include the EF-hand–containing proteins mitochondrial calcium uptake 1 （MICU1） and MICU2 and the pore-forming subunit mitochondrial calcium uniporter （MCU）. We sought to achieve a full molecular characterization of the uniporter holocomplex （uniplex）. Quantitative mass spectrometry of affinity-purified uniplex recovered MICU1 and MICU2, MCU and its paralog MCUb, and essential MCU regulator （EMRE）, a previously uncharacterized protein. EMRE is a 10-kD, metazoan-specific protein with a single transmembrane domain. In its absence, uniporter channel activity was lost despite intact MCU expression and oligomerization. EMRE was required for the interaction of MCU with MICU1 and MICU2. Hence, EMRE is essential for in vivo uniporter current and additionally bridges the calcium-sensing role of MICU1 and MICU2 with the calcium-conducting role of MCU.