First Author | Matsuzaka T | Year | 2002 |
Journal | J Lipid Res | Volume | 43 |
Issue | 1 | Pages | 107-14 |
PubMed ID | 11792729 | Mgi Jnum | J:73909 |
Mgi Id | MGI:2157178 | Citation | Matsuzaka T, et al. (2002) Dual regulation of mouse Delta(5)- and Delta(6)-desaturase gene expression by SREBP-1 and PPARalpha. J Lipid Res 43(1):107-14 |
abstractText | In the process of seeking sterol regulatory element-binding protein 1a (SREBP-1a) target genes, we identified and cloned a cDNA clone encoding mouse Delta(5)-desaturase (D5D). The hepatic expression of D5D as well as Delta(6)-desaturase (D6D) was highly activated in transgenic mice overexpressing nuclear SREBP-1a, -1c, and -2. Disruption of the SREBP-1 gene significantly reduced the expression of both desaturases in the livers of SREBP-1-deficient mice refed after fasting. The hepatic expression of both desaturases was downregulated by dietary PUFA, which were reported to suppress SREBP-1c gene expression. Sustained expression of hepatic nuclear SREBP-1c protein in the transgenic mice abolished the PUFA suppression of both desaturases. Although these data suggested that SREBP-1c regulates D5D and D6D expression, there was no difference in either the D5D or D6D mRNA level between fasted and refed normal mouse livers, indicating a mechanism for fasting induction of both desaturases. Administration of fibrate, a pharmacological ligand for peroxisome proliferator activating receptor alpha (PPARalpha), caused a significant increase in expression of both desaturases.The data suggested that D5D and D6D expression is dually regulated by SREBP-1c and PPARalpha, two reciprocal transcription factors for fatty acid metabolism, and could be involved in lipogenic gene regulation by producing PUFA. - Matsuzaka, T., H. Shimano, N. Yahagi, M. Amemiya-Kudo, T. Yoshikawa, A. H. Hasty, Y. Tamura, J-i. Osuga, H. Okazaki, Y. Iizuka, A. Takahashi, H. Sone, T. Gotoda, S. Ishibashi, and N. Yamada. Dual regulation of mouse Delta(5)- and Delta(6)-desaturase gene expression by SREBP-1 and PPARalpha. J. Lipid Res. 2002. 43: 107-114. |