cDNA cloning and mRNA distribution of a mouse very long‐chain acyl‐CoA synthetase

The interaction of the adrenoleukodystrophy protein (ALDP), mutated in the peroxisomal disorder X-linked adrenoleukodystrophy, and the very long-chain acyl-CoA synthetase (VLACS), the enzyme whose function is missing in this disease, remains obscure. As a first step to studying this interaction in wild type versus ALDP-deficient mice, we have cloned a VLACS cDNA from mouse liver. The 1860 bp open reading frame encodes a 620 amino acid protein with a predicted molecular mass of 70.3 kDa. By Northern blot analysis, a 2.6 kbp VLACS mRNA was highly abundant in liver and kidney and present at low levels in brain and testes. By RT-PCR VLACS mRNA was also detected in heart and lung but remained undetectable in skeletal muscle and spleen. In contrast to the peroxisomal beta-oxidation marker acyl-CoA oxidase, whose mRNA level steadily increases during brain development, the VLACS transcript was found at a constant low level from embryo through adulthood, suggesting that additional isoforms may exist in brain.