Ovcharova I V, Eremina S Iu, Mironov A S
State Research Institute of Genetics and Selection of Industrial Microorganisms, Moscow, 113545 Russia.
Genetika. 2004 Jan;40(1):15-25.
Effect of mutations in the -10 and -35 regions of the udp gene promoter on the nature of its regulation by CytR and CRP proteins was studied. In studies of expression of mutant promoters, competition between RNA polymerase and the CytR repressor for the promoter region of the udp gene was shown. In the presence of the improved -10 region, the introduction of a substitution 15C-->T (that is the presence of the elongated Pribnow block) resulted in the CRP-independent transcription of the udp gene promoter. The binding site CRP2 was shown to be indispensable for the maximum promoter activation by the transcription-activating cAMP-CRP complex. Both positive (cAMP-CRP complex) and negative (CytR) regulation of the promoter was virtually fully abolished after the introduction of mutations leading to the creation of canonical sequences in -10 and -35 promoter regions.
研究了udp基因启动子 -10和 -35区域的突变对其受CytR和CRP蛋白调控性质的影响。在突变启动子表达的研究中，显示了RNA聚合酶与CytR阻遏物在udp基因启动子区域的竞争。在存在改进的 -10区域的情况下，引入15C→T取代（即存在延长的Pribnow框）导致udp基因启动子的CRP非依赖性转录。已表明结合位点CRP2对于转录激活的cAMP-CRP复合物实现最大启动子激活是必不可少的。在 -10和 -35启动子区域引入导致产生规范序列的突变后，启动子的正向（cAMP-CRP复合物）和负向（CytR）调控实际上几乎完全被消除。
