Aneja Kawalpreet K, Guha Prajna, Shilpi Rasheda Y, Chakraborty Sanjoy, Schramm Laura M, Haldar Dipak
Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, NY 11439, USA.
Arch Biochem Biophys. 2008 Feb 1;470(1):35-43. doi: 10.1016/j.abb.2007.10.019. Epub 2007 Nov 4.
Sequence analysis using the Promoser program predicted two promoter-like regions for rat mtGPAT: a distal promoter approximately 30kb upstream and a proximal promoter near the first translational codon. Rat liver cells transfected with pGL3-basic vector containing the distal and proximal promoter resulted in 10.8- and 4.8-fold increase in the luciferase activity, respectively. Results of electromobility shift assay and chromatin immunoprecipitation suggested binding of transcription factors to the distal and proximal promoter regions. 5' RACE PCR showed two transcripts with different transcriptional start sites. When transfected rat liver cells were starved and refed, there was about 2.7-fold increase in the luciferase activity with cells transfected with the distal promoter while the proximal promoter showed no change. Thus, the two promoters could be functionally distinguished. Taken together, the results suggest that there are two promoters for rat mtGPAT gene and that the transcriptional regulation is mediated through the distal promoter.
使用Promoser程序进行的序列分析预测大鼠线粒体甘油磷酸酰基转移酶（mtGPAT）有两个类似启动子的区域：一个位于上游约30kb处的远端启动子和一个靠近第一个翻译密码子的近端启动子。用含有远端和近端启动子的pGL3 - 基本载体转染大鼠肝细胞，分别导致荧光素酶活性增加10.8倍和4.8倍。电泳迁移率变动分析和染色质免疫沉淀结果表明转录因子与远端和近端启动子区域结合。5' RACE PCR显示有两个具有不同转录起始位点的转录本。当转染的大鼠肝细胞饥饿后再喂食时，用远端启动子转染的细胞中荧光素酶活性增加约2.7倍，而近端启动子则无变化。因此，这两个启动子在功能上可以区分。综上所述，结果表明大鼠mtGPAT基因有两个启动子，并且转录调控是通过远端启动子介导的。
