Import of a mutant mitochondrial precursor fails to respond to stimulation by a cytosolic factor.
Import of the precursor to ornithine carbamyltransferase is stimulated by a partially-purified, NEM-sensitive soluble factor from rabbit reticulocyte lysate. A mutant in which the carboxy-terminal 73 amino acids were deleted, had a sharply reduced response to this factor. The NEM-sensitive, import-stimulating factor interacts with the surface of mitochondria in the absence of precursor protein. Thus reticulocyte lysate contains an NEM-sensitive, import stimulating factor which interacts both with the surface of mitochondria and whose activity appears to be dependent upon the structure of the mature portion of the precursor.
Randall
S K
SK
Department of Biochemistry, McGill University, Montreal, Quebec, Canada.
Shore
G C
GC
D000595:Amino Acid Sequence; D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D005033:Ethylmaleimide / Q000494:pharmacology; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D008929:Mitochondria, Heart / Q000201:enzymology / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D009954:Ornithine Carbamoyltransferase / Q000235:genetics*; D011498:Protein Precursors / Q000235:genetics* / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D012156:Reticulocytes / Q000378:metabolism*
D008565:Membrane Proteins; D011498:Protein Precursors; D009954:Ornithine Carbamoyltransferase; D005033:Ethylmaleimide