Ohyama Y, Noshiro M, Eggertsen G, Gotoh O, Kato Y, Björkhem I, Okuda K
Department of Biochemistry, Hiroshima University School of Dentistry, Japan.
Biochemistry. 1993 Jan 12;32(1):76-82. doi: 10.1021/bi00052a011.
The structural gene encoding 25-hydroxyvitamin D3 24-hydroxylase (P-450cc24) was isolated from the rat genomic DNA. It spans approximately 15 kb, is composed of 12 exons, and was demonstrated by Southern blot analysis to be present as a single copy. One major T residue was identified at the cap site, a putative TATA (ATAAATA) box was located at position -30, and a putative CCAAT box was at -58. Four possible vitamin D responsive elements that may be involved in regulation of 24-hydroxylase expression were found in the 5'-flanking region. Alignment with mitochondrial P-450 proteins showed that 7 out of 11 intron insertion sites of P-450cc24 gene occupied positions identical with those in the CYP11 family (P-450scc, P-450(11 beta)). The structure of the gene is discussed in relation to present knowledge about the mechanism of regulation of the 25-hydroxyvitamin D3 24-hydroxylase and calcium homeostasis.
从大鼠基因组DNA中分离出编码25-羟基维生素D3 24-羟化酶（P-450cc24）的结构基因。它跨度约15kb，由12个外显子组成，Southern印迹分析表明其以单拷贝形式存在。在帽位点鉴定出一个主要的T残基，一个推定的TATA（ATAAATA）框位于-30位，一个推定的CCAAT框位于-58位。在5'侧翼区域发现了四个可能参与24-羟化酶表达调控的维生素D反应元件。与线粒体P-450蛋白比对显示，P-450cc24基因的11个内含子插入位点中有7个与CYP11家族（P-450scc，P-450(11β)）中的位置相同。结合目前关于25-羟基维生素D3 24-羟化酶调控机制和钙稳态的知识，对该基因的结构进行了讨论。
