Is cytochrome P-450scc a transmembrane protein?
The topology of cytochrome P-450scc in the inner mitochondrial membrane of adrenal cortex has been investigated using monospecific antibodies to cytochrome P-450scc and its fragments F1 (Ile1-Arg250), F2 (Asn257-Ala481) and F3 (Asn257-Arg399). Antibodies to F1 and F2 were shown to effectively bind to the matrix and cytosolic sides of the inner membrane. Antibodies to F3 specifically interacted only with the matrix side of the membrane. These data are consistent with a model of molecular organization which shows that cytochrome P-450scc is a transmembrane protein, both N- and C-terminal sequences of the cytochrome being able to span the membrane.
Usanov
S A
SA
Protein Chemistry Laboratory, BSSR Academy of Sciences, Minsk, USSR.
Chernogolov
A A
AA
Chashchin
V L
VL
D000302:Adrenal Cortex / Q000201:enzymology / Q000648:ultrastructure; D000818:Animals; D002417:Cattle; D002786:Cholesterol Side-Chain Cleavage Enzyme / Q000276:immunology / Q000648:ultrastructure*; D066298:In Vitro Techniques; D007425:Intracellular Membranes / Q000201:enzymology; D008565:Membrane Proteins / Q000737:chemistry* / Q000276:immunology; D008928:Mitochondria / Q000201:enzymology* / Q000648:ultrastructure; D010084:Oxidation-Reduction; D010446:Peptide Fragments / Q000276:immunology; D013057:Spectrum Analysis; D014357:Trypsin / Q000494:pharmacology
D008565:Membrane Proteins; D010446:Peptide Fragments; D002786:Cholesterol Side-Chain Cleavage Enzyme; D014357:Trypsin