Colocalization of cell division proteins FtsZ and FtsA to cytoskeletal structures in living Escherichia coli cells by using green fluorescent protein
Colocalization of cell division proteins FtsZ and FtsA to cytoskeletal structures in living Escherichia coli cells by using green fluorescent protein
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DOI：
10.1073/pnas.93.23.12998
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发表时间：
1996-11-12
影响因子：
11.1
通讯作者：
Margolin, W
中科院分区：
文献类型：
--
作者：
Ma, XL;Ehrhardt, DW;Margolin, W
在目前的细菌细胞分裂模型中，FtsZ蛋白养殖一个标记分裂平面的环，为其他蛋白质（如FtsA）的后续作用创造细胞骨架框架。在此，我报告了用绿色荧光蛋白（GFP）标记的FtsZ和FtsA蛋白在活细菌细胞中共定位于分离的类核之间的可见空间中的分裂位点环状结构，具有更高水平的FtsZ-GFP或具有FtsA-GFP加上过量的野生型GFP的细胞。FtsZ型的细胞分裂受到抑制，并且经常显示跨越丝状细胞长度的明亮荧光螺旋小管，这表明FtsZ在某些条件下可以从有分隔能力的定域环转变为非定域螺旋，并且FtsA可以以两种构象与FtsZ结合，FtsZ-GFP还在较高浓度下形成非生产性但局部聚集体，其可以代表FtsZ成核位点。FtsZ-GFP的一般结构域结构类似于微管蛋白的结构域结构，因为FtsZ的C末端不是聚合所需的，但可以调节聚合状态，根瘤菌FtsZ的N端部分在大肠杆菌中聚合，并与大肠杆菌发生共聚。对FtsA-GFP的几个缺失的分析表明，FtsA的多个片段对于其定位于FtsZ环是重要的。
In the current model for bacterial cell division, FtsZ protein farms a ring that marks the division plane, creating a cytoskeletal framework for the subsequent action of other proteins such as FtsA. This putative protein complex ultimately generates the division septum, Herein me report that FtsZ and FtsA proteins tagged with green fluorescent protein (GFP) colocalize to division-site ring-like structures in living bacterial cells in a visible space between the segregated nucleoids, Cells with higher levels of FtsZ-GFP or with FtsA-GFP plus excess wild-type FtsZ were inhibited for cell division and often exhibited bright fluorescent spiral tubules that spanned the length of the filamentous cells, This suggests that FtsZ may switch from a septation-competent localized ring to an unlocalized spiral under some conditions and that FtsA can bind to FtsZ in both conformations, FtsZ-GFP also formed nonproductive but localized aggregates at a higher concentration that could represent FtsZ nucleation sites, The general domain structure of FtsZ-GFP resembles that of tubulin, since the C terminus of FtsZ is not required for polymerization but may regulate polymerization state, The N-terminal portion of Rhizobium FtsZ polymerized in Escherichia coli and appeared to copolymerize with E. coli FtsZ, suggesting a degree of interspecies functional conservation, Analysis of several deletions of FtsA-GFP suggests that multiple segments of FtsA are important for its localization to the FtsZ ring.