Molecular cloning and tissue expression of human mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase.

Mitochondrial 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) synthase is a constituent of the HMG-CoA pathway responsible for ketone body synthesis and one of its main regulatory points. We report the isolation and characterization of a 2058-bp cDNA from human liver. This cDNA encodes a polypeptide of 508 residues and 56,635 Da. The homology with previously reported rat mitochondrial and human cytosolic HMG-CoA synthases is 88 and 66%, respectively. mRNA levels were high in liver and colon, low in testis, heart, skeletal muscle, and kidney, and faint in pancreas.