Fong S L
Department of Ophthalmology, Indiana University, Indianapolis 46202.
Nucleic Acids Res. 1992 Jun 11;20(11):2865-70. doi: 10.1093/nar/20.11.2865.
The human rod transducin alpha subunit (Tr alpha) gene has been cloned. A cDNA clone, HG14, contained a 1.1 kb insertion when compared with the human Tr alpha cDNA published by Van Dop et al. (1). Based on two overlapping clones isolated from a human genomic library, the human Tr alpha gene is 4.9 kb in length and consists of nine exons interrupted by eight introns. Northern blots of human retina total RNA showed that the gene is transcribed by rod photoreceptors into two species of mRNA, 1.3 kb and 2.4 kb in size. Apparently, this is the result of alternative splicing. Two putative transcription initiation sites were determined by primer extension and S1 nuclease protection assays. The putative promoter regions of the human and mouse Tr alpha genes have an identity of 78.1%. As found in the mouse gene (2), no TATA consensus sequence is present in the human gene.
人类视杆转导蛋白α亚基（Trα）基因已被克隆。与Van Dop等人（1）发表的人类Trα cDNA相比，一个cDNA克隆HG14含有1.1 kb的插入片段。基于从人类基因组文库中分离出的两个重叠克隆，人类Trα基因长度为4.9 kb，由9个外显子和8个内含子间隔组成。人类视网膜总RNA的Northern印迹显示，该基因由视杆光感受器转录为两种大小分别为1.3 kb和2.4 kb的mRNA。显然，这是选择性剪接的结果。通过引物延伸和S1核酸酶保护试验确定了两个推定的转录起始位点。人类和小鼠Trα基因的推定启动子区域具有78.1%的同一性。如在小鼠基因（2）中发现的那样，人类基因中不存在TATA共有序列。
