DEGRADATION OF SIGMA(32), THE HEAT-SHOCK REGULATOR IN ESCHERICHIA-COLI IS GOVERNED BY HFLB
DEGRADATION OF SIGMA(32), THE HEAT-SHOCK REGULATOR IN ESCHERICHIA-COLI IS GOVERNED BY HFLB
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DOI：
10.1073/pnas.92.8.3516
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发表时间：
1995-04-11
影响因子：
11.1
通讯作者：
BOULOC, P
中科院分区：
文献类型：
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作者：
HERMAN, C;THEVENET, D;BOULOC, P
大肠杆菌中的热休克反应受高度不稳定的σ因子σ的浓度控制（32）。已知控制噬菌体λ cII蛋白的蛋白水解的必需蛋白HflB（FtsH）也控制σ（32）降解：HflB耗尽的菌株积累σ（32）并诱导热休克反应，并且σ（32）的半衰期在具有降低的HflB功能的突变体中增加高达12倍，并且在过表达HflB的菌株中减少1.8倍。hflB基因位于ftsJ-hflB操纵子中，其中一个启动子受热休克和sigma正调控（32）。稳定sigma（32）和lambda cII的lambda cIII蛋白似乎抑制HflB控制的蛋白酶。急诊大肠杆菌HflB蛋白控制两个主要调节因子λ cII和σ（32）的稳定性，这两个主要调节因子负责噬菌体λ的裂解-溶原性决定和宿主的热休克反应。
The heat shock response in Escherichia coli is governed by the concentration of the highly unstable sigma factor sigma(32). The essential protein HflB (FtsH), known to control proteolysis of the phage lambda cII protein, also governs sigma(32) degradation: an HflB-depleted strain accumulated sigma(32) and induced the heat shock response, and the half-life of sigma(32) increased by a factor up to 12 in mutants with reduced HflB function and decreased by a factor of 1.8 in a strain overexpressing HflB. The hflB gene is in the ftsJ-hflB operon, one promoter of which is positively regulated by heat shock and sigma(32). The lambda cIII protein, which stabilizes sigma(32) and lambda cII, appears to inhibit the HflB-governed protease. The E. coli HflB protein controls the stability of two master regulators, lambda cII and sigma(32), responsible for the lysis-lysogeny decision of phage lambda and the heat shock response of the host.