Assignment of the PSST subunit gene of human mitochondrial complex I to chromosome 19p13.
The cDNA for the PSST subunit of human mitochondrial nicotinamide adenine dinucleotide (NADH): ubiquinone oxidoreductase [complex I; NADH dehydrogenase (ubiquinone), Fe-S (20 kDa); EC 1.6.5.3] was generated by polymerase chain reaction (PCR) amplification of human cDNA. The sequence of the mature protein deduced from the cDNA codes for a protein that is closely related to the bovine protein (93% homology). Nine conservative substitutions are found in the mature protein, mainly in the N and C terminal regions. The mature human protein is missing four amino acids (PAAL) close to the N terminus that are present in the bovine protein. The N terminus of the mature protein is preceded by a presequence of 38 amino acids that, although quite different from its bovine counterpart (52% homology), has properties that are characteristic of a mitochondrial import sequence. Southern hybridization analysis predicts an estimated gene size of 3.8 kb. Northern hybridization analysis of mRNA from fibroblasts of complex I-deficient patients revealed no size or transcript level abnormalities. The cDNA of the PSST protein was used to investigate tissue-specific expression and to localize the gene for this subunit to chromosome 19p13.
Hyslop
S J
SJ
Department of Biochemistry, University of Toronto, Canada.
Duncan
A M
AM
Pitkänen
S
S
Robinson
B H
BH
D000818:Animals; D002417:Cattle; D002460:Cell Line; D002888:Chromosomes, Human, Pair 19 / Q000235:genetics*; D018076:DNA, Complementary / Q000235:genetics; D005347:Fibroblasts / Q000737:chemistry; D005796:Genes; D006801:Humans; D008928:Mitochondria / Q000201:enzymology*; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000737:chemistry / Q000172:deficiency / Q000235:genetics*; D016133:Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity
D018076:DNA, Complementary; D016660:NAD(P)H Dehydrogenase (Quinone)