Nakatani Y, Brenner M, Freese E
Laboratory of Molecular Biology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892.
Proc Natl Acad Sci U S A. 1990 Jun;87(11):4289-93. doi: 10.1073/pnas.87.11.4289.
The gfa gene encodes glial fibrillary acidic protein (GFAP), an intermediate-filament protein expressed primarily in glial cells. We have used in vitro transcription studies to show that the basal level of transcription of the human gene encoding GFAP is controlled by two distinct initiators--i.e., promoter elements that direct transcription from a specific start site. One initiator is located about 25 base pairs upstream from the transcription start site, contains a TATA box, and apparently acts together with a sequence found around the transcription start site. The other initiator is located between +11 and +50 bp downstream from the transcription start site. Most of this second region overlaps with the protein-encoding sequence, which starts at bp +17. The sensitivity of transcription to alpha-amanitin indicates that both initiators are used by RNA polymerase II.
gfa基因编码胶质纤维酸性蛋白（GFAP），这是一种主要在神经胶质细胞中表达的中间丝蛋白。我们利用体外转录研究表明，编码GFAP的人类基因的基础转录水平受两个不同的起始子控制，即从特定起始位点指导转录的启动子元件。一个起始子位于转录起始位点上游约25个碱基对处，包含一个TATA盒，并且显然与转录起始位点周围发现的一个序列共同起作用。另一个起始子位于转录起始位点下游+11至+50碱基对之间。第二个区域的大部分与从碱基对+17开始的蛋白质编码序列重叠。转录对α-鹅膏蕈碱的敏感性表明，这两个起始子都被RNA聚合酶II所利用。
