Davey H W, Ogg S L, Husaini Y, Snell R G, Korobko I V, Mather I H, Wilkins R J
AgResearch, Ruakura Research Centre, Hamilton, New Zealand.
Gene. 1997 Oct 15;199(1-2):57-62. doi: 10.1016/s0378-1119(97)00346-6.
The complete sequence of the bovine butyrophilin gene (BTN) is described and compared with the mouse gene (Btn). Both genes contain seven exons separated by six introns, and the organisation of exons is closely associated with structural domains of the protein. Individual exons of BTN and Btn are 68-87% similar in sequence. There are no canonical TATA or CCAAT boxes associated with the transcription initiation sites in the genes of either species. However, a number of potential binding sites for transcription factors were identified in the 5'-flanking DNA, some of which may function in regulating expression of the gene in mammary tissue. Conservation of a 110-bp region in the promoters of BTN and Btn may have some functional significance. Cloning and sequencing of BTN provides an additional mammary-specific gene promoter that may be used for driving the expression of transgenes in the lactating mammary gland, and for determining the basis for tissue-specific gene expression. In addition, the sequence of BTN may be used to map intragenic polymorphisms and identify quantitative trait loci in commercial livestock.
本文描述了牛嗜乳脂蛋白基因（BTN）的完整序列，并与小鼠基因（Btn）进行了比较。两个基因均包含七个外显子，由六个内含子隔开，且外显子的组织与蛋白质的结构域密切相关。BTN和Btn的各个外显子在序列上有68-87%的相似性。在这两个物种的基因中，均不存在与转录起始位点相关的典型TATA或CCAAT框。然而，在5'侧翼DNA中鉴定出了一些潜在的转录因子结合位点，其中一些可能在调节乳腺组织中该基因的表达方面发挥作用。BTN和Btn启动子中110bp区域的保守性可能具有一定的功能意义。BTN的克隆和测序提供了一个额外的乳腺特异性基因启动子，可用于驱动转基因在泌乳乳腺中的表达，以及确定组织特异性基因表达的基础。此外，BTN的序列可用于绘制基因内多态性图谱，并识别商业家畜中的数量性状位点。
