Premium
An extremely acidic amino‐terminal presequence of the precursor for the human mitochondrial hinge protein
Author(s) -
Ohta Shigeo,
Goto Kimihiko,
Arai Hajime,
Kagawa Yasuo
Publication year - 1987
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(87)80573-2
Subject(s) - biochemistry , amino acid , mitochondrion , complementary dna , biology , peptide sequence , cytochrome c , protein subunit , respiratory chain , microbiology and biotechnology , gene
Mitochondrial hinge protein is a subunit of ubiquinol‐cytochrome‐ c reductase in the respiratory chain and ‘hinges’ cytochrome c with cytochrome c 1 . The protein is encoded in the nuclear genome, synthesized in the cytosol and then imported into the mitochondria. The cDNA of the human hinge protein has been cloned and its nucleotide sequence was determined. The deduced primary structure of the amino‐terminal presequence consists of 13 amino acid residues, of which 4 amino acids are acidic and only one is basic. Since the presequences of most other precursors are rich in basic amino acids, this sequence is unique for targeting mitochondria. Expression of the gene was repressed in the presence of a phorbol ester in human promyelocyticleukemia cells (HL‐60), and this repression was greater than that of the ADP/ATP translocator. These findings suggest that the hinge protein, the expression of which is well regulated, is imported into mitochondria via a specific pathway.