Interaction network among Escherichia coli membrane proteins involved in cell division as revealed by bacterial two-hybrid analysis
Interaction network among Escherichia coli membrane proteins involved in cell division as revealed by bacterial two-hybrid analysis
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DOI：
10.1128/jb.187.7.2233-2243.2005
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发表时间：
2005-04-01
影响因子：
3.2
通讯作者：
Ladant, D
中科院分区：
文献类型：
--
作者：
Karimova, G;Dautin, N;Ladant, D
大肠杆菌分裂隔膜的形成是由许多必需蛋白(称为FTS)催化的，这些蛋白质在未来的分裂位点组装成环状结构。这些FTS蛋白中有几个是固有的跨膜蛋白，其功能在很大程度上是未知的。尽管这些蛋白质似乎是按等级顺序被招募到分裂部位的，但细胞分裂机制组装背后的分子相互作用大多仍未明确。在本研究中，我们使用了一个基于cAMP(CAMP)信号级联相互作用的细菌双杂交系统，通过分析大肠杆菌细胞分裂蛋白之间的蛋白质相互作用网络来揭示隔膜组装的分子基础。我们的结果表明，FTS蛋白通过多个相互作用相互连接。对其中两种蛋白质FtsQ和FTSI进行的缺失图谱分析表明，多肽的不同区域参与了它们与伴侣的联系。此外，我们还表明，两个FTS杂合蛋白之间的联系可以通过第三个FTS伙伴的共表达来调节。综上所述，这些数据表明，细胞分裂机械组装是由不同FTS蛋白之间的合作结合驱动的，在隔膜位置形成动态的多蛋白质结构。此外，我们的研究表明，基于cAMP的双杂交系统特别适合于分析膜蛋白之间的分子相互作用。
Formation of the Escherichia coli division septum is catalyzed by a number of essential proteins (named Fts) that assemble into a ring-like structure at the future division site. Several of these Fts proteins are intrinsic transmembrane proteins whose functions are largely unknown. Although these proteins appear to be recruited to the division site in a hierarchical order, the molecular interactions underlying the assembly of the cell division machinery remain mostly unspecified. In the present study, we used a bacterial two-hybrid system based on interaction-mediated reconstitution of a cyclic AMP (cAMP) signaling cascade to unravel the molecular basis of septum assembly by analyzing the protein interaction network among E. coli cell division proteins. Our results indicate that the Fts proteins are connected to one another through multiple interactions. A deletion mapping analysis carried out with two of these proteins, FtsQ and FtsI, revealed that different regions of the polypeptides are involved in their associations with their partners. Furthermore, we showed that the association between two Fts hybrid proteins could be modulated by the coexpression of a third Fts partner. Altogether, these data suggest that the cell division machinery assembly is driven by the cooperative association among the different Fts proteins to form a dynamic multiprotein structure at the septum site. In addition, our study shows that the cAMP-based two-hybrid system is particularly appropriate for analyzing molecular interactions between membrane proteins.