Burova E, Gottesman M E
Institute of Cancer Research, College of Physicians and Surgeons of Columbia University, New York, New York 10032, USA.
Mol Microbiol. 1995 Aug;17(4):633-41. doi: 10.1111/j.1365-2958.1995.mmi_17040633.x.
The Escherichia coli NusG protein binds Rho in vitro and is required for efficient Rho-dependent transcription termination in vivo. In this work we examine transcription termination in cells that over-express NusG. Termination at the Rho-dependent lambda tL1 and lambda tR1 sites was significantly inhibited by excess NusG, whereas the Rho-independent lambda tl site was fully functional. Although Western analysis showed no reduction in the levels of soluble Rho, termination was restored when Rho was also overexpressed. Our data indicated that the ratio of NusG and Rho proteins affects the efficiency of transcription termination.
大肠杆菌NusG蛋白在体外可与Rho结合，且在体内高效的Rho依赖性转录终止过程中是必需的。在本研究中，我们检测了过表达NusG的细胞中的转录终止情况。过量的NusG显著抑制了Rho依赖性的λtL1和λtR1位点的终止，而Rho非依赖性的λtl位点功能完全正常。尽管蛋白质免疫印迹分析显示可溶性Rho的水平没有降低，但当Rho也过表达时，终止得以恢复。我们的数据表明，NusG和Rho蛋白的比例会影响转录终止的效率。
