Photolabelling of a mitochondrially encoded subunit of NADH dehydrogenase with [3H]dihydrorotenone.

Mitochondrial NADH dehydrogenase from bovine heart was photolabelled with the inhibitor [3H]dihydrorotenone. A constituent of the hydrophobic domain of the enzyme of Mr 33,000 was the major site of labelling. The identity of this protein with the mitochondrially encoded ND-1 gene product was established by immunoblotting and immunoprecipitation with an antiserum raised to the expected C-terminal sequence of the human ND-1 gene product.