The role of diacylglycerol acyltransferase in the accumulation and deposition of triacylglycerol in bovine tissues

摘要

The production of dairy products with nutraceutic fatty acids such as conjugated linoleic acid (CLA), and cattle with highly marbled beef represent two approaches for dairy and cattle producers to increase the value of their respective products. Bovine diacylglycerol acyltransferase-1 (DGAT1), the enzyme responsible for the final step in the biosynthesis of triacylglycerol, was studied. Intramuscular fat content, DGAT activity, and occurrence of the K232A mutation were measured in Holstein and Charolais bulls, and no significant relationship between DGAT activity and intramuscular fat content was found. With respect to milk fat production, the effect of CLA isomers on the activity and expression of DGAT was investigated in bovine mammary gland epithelial (MAC-T) cells and microsomal fractions of bovine mammary gland tissue. There were no significant effects of CLA isomers or intermediates on the expression of DGAT. Treatment of MAC-T cells with trans-10, cis-12 18:2 decreased DGAT activity, although the mechanisms are unclear.