Wyatt M K, Philpot R M, Carver G, Lawton M P, Nikbakht K N
Laboratory of Cellular and Molecular Pharmacology, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA.
Drug Metab Dispos. 1996 Dec;24(12):1320-7.
As a first step in understanding the regulation of the expression of flavin-containing monooxygenases (FMOs), we have isolated the FMO genes from the rabbit and characterized the gene for FMO1. Probes based on the 3', middle and 5' regions of the cDNAs encoding FMO1, FM02, FM03, and FM05 were generated by polymerase chain reaction. A mixture of the 5' probes was used to screen a genomic library, and isolated clones were identified by hybridization with individual 5' probes. The complete gene for FM01 was isolated as three overlapping clones and found to span approximately 40 kb. The gene contains eight introns, ranging in size from 1.4 to 10 kb and nine exons ranging in size from 73 to 747 bases. The gene for FMO1 seems to have multiple transcription start sites. A genomic clone containing a 5' segment of the FM02 gene was isolated and found to contain intron 1, exon 1, and part of intron 2. The first intron of FM02 is considerably smaller than that of FMO1 (0.3 vs. 3.8 kb), and its 3' junction is 52 bases to the 5' of the start codon, compared with 6 bases in the case of FM01. In contrast, the 5' junction of intron 2 is the same distance from the start codon in both genes. The 5'-flanking regions of the FMO1 and FM02 genes contain several putative glucocorticoid responsive elements.
作为了解含黄素单加氧酶（FMOs）表达调控的第一步，我们从兔中分离出了FMO基因，并对FMO1基因进行了表征。基于编码FMO1、FM02、FM03和FM05的cDNA的3'、中间和5'区域的探针通过聚合酶链反应产生。使用5'探针的混合物筛选基因组文库，并通过与单个5'探针杂交鉴定分离的克隆。FMO1的完整基因作为三个重叠克隆被分离出来，发现其跨度约为40 kb。该基因包含八个内含子，大小从1.4到10 kb不等，九个外显子大小从73到747个碱基不等。FMO1基因似乎有多个转录起始位点。分离出一个包含FM02基因5'片段的基因组克隆，发现其包含内含子1、外显子1和部分内含子2。FM02的第一个内含子比FMO1的小得多（0.3对3.8 kb），其3'连接处位于起始密码子5'端52个碱基处，而FMO1的为6个碱基。相比之下，内含子2的5'连接处与两个基因的起始密码子距离相同。FMO1和FM02基因的5'侧翼区域包含几个假定的糖皮质激素反应元件。
