Cascade of sigma factors in streptomycetes:: identification of a new extracytoplasmic function sigma factor σJ that is under the control of the stress-response sigma factor σH in Streptomyces coelicolor A3(2)
Cascade of sigma factors in streptomycetes:: identification of a new extracytoplasmic function sigma factor σJ that is under the control of the stress-response sigma factor σH in Streptomyces coelicolor A3(2)
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DOI：
10.1007/s00203-006-0158-9
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发表时间：
2006-12-01
影响因子：
2.8
通讯作者：
Kormanec, Jan
中科院分区：
文献类型：
--
作者：
Mazurakova, Vladislava;Sevcikova, Beatrica;Kormanec, Jan
通过使用先前建立的大肠杆菌双质粒系统，我们鉴定了天蓝色链霉菌A3(2)应激反应因子sigma(H)识别的启动子。启动子指导编码胞质外功能（ECF）sigma因子的sigJ基因的表达。使用从含有双质粒系统的大肠杆菌和来自不同发育阶段的天蓝色链球菌A3(2)制备的RNA进行S1核酸酶图谱鉴定，在两个菌株中鉴定出相同的转录起始点，对应于sigJp启动子。 sigJp启动子在气生菌丝形成孢子期间被诱导。 sigJp 的转录物水平在 S. coelicolor A3(2) sigH 突变体中显着降低，而在 sigF 突变体中不受影响。天蓝色链球菌 A3(2) 核心 RNA 聚合酶与 sigma(H) 互补后，能够在体外识别 sigJp 启动子。 sigJ突变对生长、应激反应、分化和抗生素的产生没有明显影响。结果表明，S. coelicolor A3(2) sigJ 基因受到应激反应 sigma(H) 的控制，从而表明链霉菌应激反应和发育中存在一系列 sigma 因子。考虑到 sigJ 的表达及其对发育调节 sigma(H) 的直接依赖性，我们假设 sigma(J) 可能在 S. coelicolor A3(2) 的发育后期发挥作用。
By using the previously established Escherichia coli two-plasmid system, we identified a promoter recognized by the Streptomyces coelicolor A3(2) stress-response sigma factor sigma(H). The promoter directed expression of the sigJ gene encoding an extracytoplasmic function (ECF) sigma factor. S1-nuclease mapping using RNA prepared from E. coli containing the two-plasmid system, and S. coelicolor A3(2) from various developmental stages identified an identical transcription start point in both strains, corresponding to the sigJp promoter. The sigJp promoter was induced during sporulation of aerial hyphae. The level of the transcript from sigJp was dramatically reduced in a S. coelicolor A3(2) sigH mutant and unaffected in a sigF mutant. The S. coelicolor A3(2) core RNA polymerase, after complementation with sigma(H), was able to recognize the sigJp promoter in vitro. A sigJ mutation had no obvious effect on growth, stress response, differentiation, and production of antibiotics. The results suggested that the S. coelicolor A3(2) sigJ gene is under the control of stress-response sigma(H), thus indicating a cascade of sigma factors in Streptomyces stress response and development. Considering the expression of sigJ and its direct dependence upon developmentally-regulated sigma(H), we assume that sigma(J) may play a role in the later stages of development of S. coelicolor A3(2).