Cell division protein DivIB influences the Spo0J/Soj system of chromosome segregation in Bacillus subtilis
Cell division protein DivIB influences the Spo0J/Soj system of chromosome segregation in Bacillus subtilis
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细胞分裂蛋白 DivIB 影响枯草芽孢杆菌染色体分离的 Spo0J/Soj 系统
作者：
G. Real;S. Autret;E. Harry;J. Errington;A. Henriques
棒状细菌枯草芽孢杆菌孢子形成的发育过程涉及Spo0A反应调节因子的激活。然后，Spo0A驱动分裂间隔形成部位的开关从中细胞到极性位置。活化的Spo0A是转录关键孢子形成位点（如spoIIG）所必需的，而spoIIG是由Soj蛋白负调控的。Soj的转录抑制活性可被Spo0J拮抗，这两种蛋白都属于保守度较高的Par蛋白家族。Soj已被证明通过细胞极从类核跳到类核。Soj的动态行为在某种程度上是由Spo0J控制的，它阻止了Soj与类核的静态结合，可能也阻止了其转录抑制活性。Soj反过来又需要在oriC区域周围适当地凝聚Spo0J焦点。孢子囊细胞的不对称分裂需要DivIB和其他参与营养（内侧）分裂的蛋白质。我们描述了细胞分裂基因divIB （divIB80）的一个等位基因，它降低了细胞中divIB的水平，并影响生长细胞中的类核结构和分离，但对细胞分裂没有主要影响。在divIB80细胞中，Spo0J灶不能正确凝聚，Soj静态地与类核结合。divIB80等位基因阻止spoIIG的转录，并在不对称分裂间隔形成之前阻止孢子形成。Spo0A依赖性基因表达的缺陷和Spo -表型可以通过反式中divIB的表达或soj‐spo0J位点的缺失来抑制。然而，删除spo0J‐soj区域并不能恢复DivIB的正常细胞水平。因此，在divIB80突变体中，降低的DivIB水平足以实现有效的细胞分裂，但不能维持与染色体分离的Spo0J/Soj系统活性相关的第二种、早期的DivIB功能。
The initiation of the developmental process of sporulation in the rod‐shaped bacterium Bacillus subtilis involves the activation of the Spo0A response regulator. Spo0A then drives the switch in the site of division septum formation from midcell to a polar position. Activated Spo0A is required for the transcription of key sporulation loci such as spoIIG, which are negatively regulated by the Soj protein. The transcriptional repressing activity of Soj is antagonized by Spo0J, and both proteins belong to the well‐conserved Par family of partitioning proteins. Soj has been shown to jump from nucleoid to nucleoid via the cell pole. The dynamic behaviour of Soj is somehow controlled by Spo0J, which prevents the static association of Soj with the nucleoid, and presumably its transcriptional repression activity. Soj in turn is required for the proper condensation of Spo0J foci around the oriC region. The asymmetric partitioning of the sporangial cell requires DivIB and other proteins involved in vegetative (medial) division. We describe an allele of the cell division gene divIB (divIB80) that reduces the cellular levels of DivIB, and affects nucleoid structure and segregation in growing cells, yet has no major impact on cell division. In divIB80 cells Spo0J foci are not correctly condensed and Soj associates statically with the nucleoid. The divIB80 allele prevents transcription of spoIIG, and arrests sporulation prior to the formation of the asymmetric division septum. The defect in Spo0A‐dependent gene expression, and the Spo– phenotype can be suppressed by expression of divIB in trans or by deletion of the soj‐spo0J locus. However, deletion of the spo0J‐soj region does not restore the normal cellular levels of DivIB. Therefore, the reduced levels of DivIB in the divIB80 mutant are sufficient for efficient cell division, but not to sustain a second, earlier function of DivIB related to the activity of the Spo0J/Soj system of chromosome segregation.
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枯草芽孢杆菌 spoIIA 基因座的转录。
影响因子：
3.5
作者：
Wu,JJ;Piggot,PJ;Tatti,KM;MoranJr,CP
通讯作者：
MoranJr,CP
在枯草芽孢杆菌孢子形成过程中，Spo0A 与 sigma A RNA 聚合酶使用的启动子结合。
DOI：
10.1073/pnas.88.10.4533
发表时间：
1991
影响因子：
11.1
作者：
Satola,S;Kirchman,PA;MoranJr,CP
通讯作者：
MoranJr,CP
影响因子：
10.5
作者：
Levin, PA;Losick, R
通讯作者：
Losick, R
影响因子：
16
作者：
Lemon, KP;Grossman, AD
通讯作者：
Grossman, AD
影响因子：
16
作者：
Quisel, JD;Lin, DCH;Grossman, AD
通讯作者：
Grossman, AD