期刊
MOLECULAR MICROBIOLOGY
卷 69, 期 2, 页码 534-547出版社
WILEY
DOI: 10.1111/j.1365-2958.2008.06306.x
关键词
-
Lon protease is a major protease in cellular protein quality control, but also plays an important regulatory role by degrading various naturally unstable regulators. Here, we traced additional such regulators by identifying regulons with co-ordinately altered expression in a lon mutant by genome-wide transcriptional profiling. Besides many members of the RcsA regulon (which validates our approach as RcsA is a known Lon substrate), many genes of the sigma(S)-dependent general stress response were upregulated in the lon mutant. However, the lon mutation did not affect sigma(S) levels nor sigma(S) activity in general, suggesting specific effects of Lon on secondary regulators involved in the control of subsets of sigma(S)-controlled genes. Lon-affected genes also included the major acid resistance genes (gadA, gadBC, gadE, hdeAB and hdeD), which led to the discovery that the essential acid resistance regulator GadE (whose expression is sigma(S)-controlled) is degraded in vivo in a Lon-dependent manner. GadE proteolysis is constitutive as it was observed even under conditions that induce the system (i.e. at low pH or during entry into stationary phase). GadE degradation was found to rapidly terminate the acid resistance response upon shift back to neutral pH and to avoid overexpression of acid resistance genes in stationary phase.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据