Splicing before import – An intein in a mitochondrially targeted preprotein folds and is catalytically active in the cytoplasm in vivo

FEBS Letters

Martin, Nancy C.²  Williams, Lisa R.²  Hopper, Anita K.³  Davis, Elaine O.¹  Ellis, Steven R.² 

[1] National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK;Department of Biochemistry and Molecular Biology, Bldg. 55A, Room 708, University of Louisville School of Medicine, 319 Abraham Flexner Way, Louisville, KY 40202, USA;Department of Biochemistry and Molecular Biology, H171, Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA

关键词: Mitochondrial import;    Protein splicing;    Saccharomyces cerevisiae;   

DOI  :  10.1016/S0014-5793(00)01736-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Nuclear-encoded mitochondrial proteins are cytoplasmically synthesized and imported into the organelle. The intein-containing RecA protein of Mycobacterium tuberculosis, with or without the CoxIVp mitochondrial targeting signal (MTS), was used to determine where a protein targeted to mitochondria folds and becomes catalytically active. Analysis of fractions from Saccharomyces cerevisiae cells expressing RecA without the MTS revealed that RecA and intein proteins remained cytoplasmic. With the MTS, most of RecA was directed to mitochondria, while most of the intein remained in the cytoplasm. The intein therefore folds into a catalytically active state in the cytoplasm prior to RecA import into mitochondria.

【 授权许可】

Unknown