Identification Of The Transgenic Integration Site In Fat-1Transgenic Cattle

Clinic studies have showed that long-chain omega-3polyunsaturated fatty acids (n-3PUFAs) have beneficial effect on human health, while high levels of n-6PUFAs in human bodies are closely related to certain diseases such as cancer, cardiovascular diseases and various mental disorders. A rational balanced level of n-6and n-3fatty acids is important and the ideal n-6/n-3ratio is1:1. Alternative resources of n-3PUAFs created by transgenic domestic animals would be an economic approach. In this study, fat-1gene, from Caenorhabditis elegans encoding an n-3fatty acid desaturase, was humanized modification and constructed transgenic vectors. The transgenic cattle were created by somatic cell nuclear transfer. In order to examine the insertion site and copy number of foreign fat-1in the transgenic founders, the ligation-mediated PCR (LM-PCR), a laboratory-saved method, was used to identify the integrated fat-1gene. The results show that, in ZK002, the fat-1gene is integrated into chromosome6with one copy. The expressions of the genes adjacent to the fat-1transgene in the same chromosome were significantly affected. However, the mRNA expression of fatty acid synthase (FAS) and acetyl CoA carboxylase (ACC) were inhibited. Analyses of fatty acids in variety of tissues showed that n-3PUFA significantly increased and simultaneously the n-6PUFA decreased, a significantly reduction of n-6/n-3ratio approximately1:1were obtained.