Precursor proteins in transit through mitochondrial contact sites interact with hsp70 in the matrix

FEBS Letters

Craig, Elizabeth A.²  Ostermann, Joachim¹  Voos, Wolfgang¹  Pfanner, Nikolaus¹  Kang, Pil Jung²  Neupert, Walter¹ 

[1] Institut für Physiologische Chemie, Universität München, Goethestr. 33, W-8000 München 2, Germany;Department of Physiological Chemistry, University of Wisconsin at Madison, Madison, WI 53706, USA

关键词: Mitochondria;    hsp70;    Contact site;    Protein transport;    ADP/ATP carrier;   

DOI  :  10.1016/0014-5793(90)80865-G

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We previously reported that hsp70 in the mitochondrial matrix (mt-hsp70 = Ssc1p) is required for import of precursor proteins destined for the matrix or intermembrane space. Here we show that mt-hsp70 is also needed for the import of mitochondrial inner membrane proteins. In particular, the precursor of ADP/ATP carrier that is known not to interact with hsp60 on its assembly pathway requires functional mt-hsp70 for import, suggesting a general role of mt-hsp70 in membrane translocation of precursors. Moreover, a precursor arrested in contact sites was specifically co-precipitated with antibodies directed against mt-hsp70. We conclude that mt-hsp70 is directly involved in the translocation of many, if not all, precursor proteins that are transported across the inner membrane.

【 授权许可】

Unknown