부산대학교 도서관

The family of proteins that includes very long-chain acyl-CoA synthetases (ACSVL) consists of six members. These enzymes have also been designated fatty acid transport proteins. We cloned full-length mouse Acsv13 cDNA and characterized its protein product ACSVL3/ fatty acid transport protein 3. The predicted amino acid sequence contains two highly conserved motifs characteristic of acyl-CoA synthetases. Northern blot analysis revealed that the mouse Acsv13 mRNA is highly expressed in adrenal gland, testis, and ovary, with lower expression in the brain of adult mice. A developmental Northern blot revealed that Acsv13 mRNA levels were significantly higher in embryonic mouse brain (embryonic days 12–14) than in newborn or adult mice, suggesting a possible role in nervous system development. Immunohistochemistry revealed high ACSVL3 expression in adrenal cortical cells, spermatocytes and interstitial cells of the testis, theca cells of the ovary, cerebral cortical neurons, and cerebellar Purkinje cells. Endogenous ACSVL3 was found primarily in mitochondria of MA-10 and Neuro2a cells by both Western blot analysis of subcellular fractions and immunofluorescence analy- sis. In MA-10 cells, loss-of-function studies using RNA interference confirmed that endogenous ACSVL3 is an acyl-CoA synthetase capable of activating both long- chain (C16:0) and very long-chain (C24:0) fatty acids. However, despite decreased acyl-CoA synthetase activity, initial rates of fatty acid uptake were unaffected by knockdown of Acsv13 expression in MA-10 cells. These studies cast doubt on the designation of ACSVL3 as a fatty acid transport protein. [ABSTRACT FROM AUTHOR]