Sequence of the precursor of bovine liver mitochondrial aldehyde dehydrogenase as determined from its cDNA, its gene, and its functionality.

The partial sequence coding for bovine liver mitochondrial aldehyde dehydrogenase was previously reported (Farres, J., Guan, K.L., and Weiner, H., 1989, Eur. J. Biochem. 180, 67-74); cDNA coding for the N-terminal region has now been obtained by primer extension. The deduced 520 amino acids contained 499 residues corresponding to the mature mitochondrial aldehyde dehydrogenase which was one residue shorter than other mammalian mitochondrial aldehyde dehydrogenases. The N-terminal signal peptide had only 21 amino acids but showed high sequence identity to the signal sequences of human and rat enzymes, which have 17 and 19 amino acids, respectively, and had general characteristic features of typical mitochondrial signal peptides. Although the direct protein sequence of the signal peptide was not available, a mRNA coding for a 57-kDa precursor was proven to exist. The bovine signal peptide was able to direct the import of bovine aldehyde dehydrogenase precursor into isolated liver mitochondria. The complete nuclear gene coding for bovine mitochondrial aldehyde dehydrogenase was found to span at least 25 kb. A restriction map of this gene was constructed. Two potential transcription start sites were identified by primer extension and S1 nuclease protection. Several SpI transcription factor recognition sequences were found in the 5'-region of the gene. TATA box and CAAT box like sequences were found to be exist 18 and 64 bp upstream from the major transcription start site, respectively.