Evidence that metabolism and chromosome copy number control mutually exclusive cell fates in Bacillus subtilis
Evidence that metabolism and chromosome copy number control mutually exclusive cell fates in Bacillus subtilis
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DOI：
10.1038/emboj.2011.36
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发表时间：
2011-04-06
期刊：
影响因子：
11.4
通讯作者：
Losick, Richard
中科院分区：
文献类型：
--
作者：
Chai, Yunrong;Norman, Thomas;Losick, Richard
枯草芽孢杆菌选择之间的基质生产和孢子形成，这两者都是由调节Spo 0A类似于P.我们报告，代谢和染色体拷贝数决定的命运是通过。有利于低Spo 0A类似于P水平的条件促进基质生产，而有利于高水平的条件触发孢子形成。Spo 0A类似于P，指导SinI的合成，SinI是基质基因SinR阻遏物的抗阻遏物。sinI的调控区含有一个类似于P的Spo 0A强结合的激活位点和一个类似于P的Spo 0A弱结合的操纵子。有证据表明，低Spo 0A类似于P水平打开sinI ON和高水平打开sinI OFF，而不是开关孢子形成ON。细胞中，sinI和sinR从其正常位置附近的染色体复制末端的位置附近的起源和细胞，窝藏一个额外的基因拷贝被阻止在矩阵生产。因此，基质基因表达对sinI和sinR的拷贝数敏感。由于孢子形成开始时的细胞有两条染色体，而产生基质的细胞只有一条，因此染色体拷贝数可能有助于决定细胞的命运。The EMBO Journal（2011）30，1402-1413. doi：10.1038/daj.2011.36; 2011年2月15日在线发布
Bacillus subtilis chooses between matrix production and spore formation, which are both controlled by the regulator Spo0A similar to P. We report that metabolism and chromosome copy number dictate which fate is adopted. Conditions that favour low Spo0A similar to P levels promote matrix production, whereas conditions favouring high levels trigger sporulation. Spo0A similar to P directs the synthesis of SinI, an antirepressor for the SinR repressor of matrix genes. The regulatory region of sinI contains an activator site that Spo0A similar to P binds strongly and operators that bind Spo0A similar to P weakly. Evidence shows that low Spo0A similar to P levels turn sinI ON and high levels turn sinI OFF and instead switch sporulation ON. Cells in which sinI and sinR were transplanted from their normal position near the chromosome replication terminus to positions near the origin and cells that harboured an extra copy of the genes were blocked in matrix production. Thus, matrix gene expression is sensitive to the number of copies of sinI and sinR. Because cells at the start of sporulation have two chromosomes and matrix-producing cells one, chromosome copy number could contribute to cell-fate determination. The EMBO Journal (2011) 30, 1402-1413. doi: 10.1038/emboj.2011.36; Published online 15 February 2011