Nakatani Y, Nicholson W L, Neitzke K D, Setlow P, Freese E
Laboratory of Molecular Biology, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892.
Nucleic Acids Res. 1989 Feb 11;17(3):999-1017. doi: 10.1093/nar/17.3.999.
The gene encoding glucose dehydrogenase (gdh) is part of an operon whose expression is transcriptionally activated specifically in the developing forespore of Bacillus subtilis at stage III of sporulation. The in vivo startpoint of gdh transcription was determined using primer extension analysis. Deletion mapping and site-specific mutagenesis experiments indicated that the region responsible for regulated expression of gdh in vivo was limited to the "-35" and "-10" regions preceding the transcriptional start site. RNA polymerase containing omega G (E omega G) transcribed gdh in vitro with a start site identical to that found in vivo, and transcription of gdh by E omega G in vitro also did not require any specific sequences upstream from "-35" region. These results suggest that the appearance of E omega G in the forespore at stage III of sporulation is sufficient to cause temporal and compartment-specific expression of the gdh operon.
编码葡萄糖脱氢酶（gdh）的基因是一个操纵子的一部分，该操纵子的表达在枯草芽孢杆菌芽孢形成的III期发育中的前芽孢中被特异性转录激活。使用引物延伸分析确定了gdh转录的体内起始点。缺失作图和位点特异性诱变实验表明，负责gdh体内调控表达的区域仅限于转录起始位点之前的“-35”和“-10”区域。含有ωG的RNA聚合酶（EωG）在体外转录gdh，其起始位点与体内发现的相同，并且EωG在体外对gdh的转录也不需要“-35”区域上游的任何特定序列。这些结果表明，在芽孢形成III期前芽孢中出现EωG足以导致gdh操纵子的时间和区室特异性表达。
