Identification and functional analysis of human Tom22 for protein import into mitochondria.

ABSTRACT: Mitochondria have a receptor complex in the outer membrane which recognizes and translocates mitochondrial proteins synthesized in the cytosol. We report here the identification and functional analysis of human Tom22 (hTom22). hTom22 has an N-terminal negatively charged region exposed to the cytosol, a putative transmembrane region, and a C-terminal intermembrane space region with little negative charge. Tom22 forms a complex with Tom20, and its cytosolic domain functions as an import receptor as in fungi. An import inhibition assay, using pre-ornithine transcarbamylase (pOTC) derivatives and a series of hTom22 deletion mutants, showed that the C-terminal segment of the cytosolic domain is important for presequence binding, whereas the N-terminal domain is important for binding to the matu

SUBMITTER: Yano M 

PROVIDER: S-EPMC86274 | biostudies-literature | 2000 Oct

REPOSITORIES: biostudies-literature