A Novel Relative of the Very-Long-Chain Acyl-CoA Synthetase and Fatty Acid Transporter Protein Genes with a Distinct Expression Pattern

Abstract

Based on its relationship to very-long-chain acyl-CoA synthetase (VLACS), we have cloned and identified a novel, VLACS-related (VLACSR) cDNA from mouse liver. The 2067-bp open reading frame encodes a 689-amino-acid protein with a predicted molecular mass of 76.2 kDa. The carboxy-terminal 500 amino acids of VLACSR show 48% identity and 70% similarity to mouse VLACS and 43% identity and 60% similarity to mouse fatty acid transporter (FATP), respectively. In addition, a partial cDNA of the human VLACSR ortholog was identified. By Northern blot analysis, a 2.6-kb VLACS mRNA was highly abundant only in mouse liver. Low levels of shorter mRNAs were present in brain, lung, testes, and spleen (2.5 kb) and in skeletal muscle (2.2 kb). In heart, but not in kidney, transcripts undetectable by Northern blot analysis could be demonstrated by RT PCR. Southern blot analysis indicated single-copy VLACSR genes in the mouse and human genomes.