Isolation of a cDNA clone specifying rat chaperonin 10, a stress‐inducible mitochondrial matrix protein synthesised without a cleavable presequence

FEBS Letters

Ryan, Michael T.¹  Høj, Peter B.¹  Hoogenraad, Nicholas J.¹ 

[1] Department of Biochemistry, La Trobe University, Bundoora, Vic., 3083, Australia

关键词: Protein import;    Acetylation;    Amphiphilic helix;    Heat-shock protein;    cpn10;    chaperonin 10;    cpn60;    chaperonin 60;    OTC;    rat ornithine transcarbamylase;    p-OTC;    the 39 kDa precursor of OTC;   

DOI  :  10.1016/0014-5793(94)80263-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have isolated a cDNA clone encoding chaperonin 10 from rat liver. The cDNA specifies a protein of 102 amino acids which, when transcribed and translated in vitro, yields a single basic product (pI > 9) that co-migrates exactly with the heat shock inducible cpn10 of rat hepatoma cells during 2D gel-electrophoresis. It is concluded that cpn10, unlike the majority of nuclear-encoded proteins of the mitochondrial matrix, is synthesised without a cleavable targeting signal and that, following removal of the initiating methionine, it becomes acetylated prior to mitochondrial import. Incubation of ³H- or ³⁵S-labelled cpn10 with mitochondria confirms these conclusions and shows that cpn10 is imported into mitochondria in an energy-dependent process which is inhibited by the presence of 2,4-dinitrophenol.

【 授权许可】

Unknown