SlrA/SinR/SlrR inhibits motility gene expression upstream of a hypersensitive and hysteretic switch at the level of σ(D) in Bacillus subtilis.
SlrA/SinR/SlrR inhibits motility gene expression upstream of a hypersensitive and hysteretic switch at the level of σ(D) in Bacillus subtilis.
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DOI：
10.1111/j.1365-2958.2012.08003.x
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发表时间：
2012-03
影响因子：
3.6
通讯作者：
Kearns DB
中科院分区：
文献类型：
--
作者：
Cozy LM;Phillips AM;Calvo RA;Bate AR;Hsueh YH;Bonneau R;Eichenberger P;Kearns DB
指数生长的枯草芽孢杆菌培养物在表观遗传上分化为两个亚群，其中细胞的σ d依赖性基因表达为ON或OFF：一种双稳定性模式。编码σD的基因sigD是31个基因的fla/che操纵子的一部分，它位于3 '端，距离强Pfla/che启动子25 kb，决定了它相对于阈值的表达水平。本研究表明，在染色体中添加一个额外的slrA基因拷贝抑制了σ d依赖性基因的表达。SlrA与SinR和SlrR一起通过增强fla/che操纵子转录丰度的距离依赖性降低来减少sigD转录，而这种减少不是由Pfla/che启动子的表达变化介导的。与σD上游作用一致，sigD的人工异位表达可以绕过SlrA/SinR/SlrR，并在原生位点与sigD基因接合，滞回维持20代。SlrA/SinR/SlrR也通过增加fla/che转录而被绕过，从而导致鞭毛蛋白表达的超敏输出。因此，鞭毛蛋白基因表达表现出超敏性和迟滞性，因此我们认为σ d依赖性基因表达是双稳态的。
Exponentially growing Bacillus subtilis cultures are epigenetically differentiated into two subpopulations in which cells are either ON or OFF for σD-dependent gene expression: a pattern suggestive of bistability. The gene encoding σD, sigD, is part of the 31-gene fla/che operon where its location at the 3′ end, 25 kb away from the strong Pfla/che promoter, determines its expression level relative to a threshold. Here we show that addition of a single extra copy of the slrA gene in the chromosome inhibited σD-dependent gene expression. SlrA together with SinR and SlrR reduced sigD transcript by potentiating a distance-dependent decrease in fla/che operon transcript abundance that was not mediated by changes in expression from the Pfla/che promoter. Consistent with acting upstream of σD, SlrA/SinR/SlrR could be bypassed by artificial ectopic expression of sigD that hysteretically maintained for 20 generations by engaging the sigD gene at the native locus. SlrA/SinR/SlrR was also bypassed by increasing fla/che transcription and resulted a hypersensitive output in flagellin expression. Thus, flagellin gene expression demonstrated hypersensitivity and hysteresis and we conclude that σD-dependent gene expression is bistable.
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影响因子：
3.6
作者：
Kobayashi, Kazuo
通讯作者：
Kobayashi, Kazuo
影响因子：
3.5
作者：
GueroutFleury, AM;Frandsen, N;Stragier, P
通讯作者：
Stragier, P
影响因子：
3.2
作者：
BARILLA, D;CARAMORI, T;GALIZZI, A
通讯作者：
GALIZZI, A
影响因子：
3.6
作者：
Hsueh YH;Cozy LM;Sham LT;Calvo RA;Gutu AD;Winkler ME;Kearns DB
通讯作者：
Kearns DB
影响因子：
14.9
作者：
Irnov I;Sharma CM;Vogel J;Winkler WC
通讯作者：
Winkler WC