Anionic Phospholipids Stabilize RecA Filament Bundles in Escherichia coli.
Anionic Phospholipids Stabilize RecA Filament Bundles in Escherichia coli.
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阴离子磷脂可稳定大肠杆菌中的 RecA 丝束。
DOI：
10.1016/j.molcel.2015.09.009
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发表时间：
2015
期刊：
影响因子：
16
通讯作者：
Weibel,DouglasB
中科院分区：
文献类型：
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作者：
Rajendram,Manohary;Zhang,Leili;Reynolds,BradleyJ;Auer,GeorgeK;Tuson,HannahH;Ngo,KhanhV;Cox,MichaelM;Yethiraj,Arun;Cui,Qiang;Weibel,DouglasB
我们表征RecA与膜在体内和体外的相互作用，并证明RecA紧密结合的阴离子磷脂心磷脂（CL）和磷脂酰甘油（PG）。使用计算模型，我们确定了与PG和CL相互作用的RecA的两个区域：（1）N-末端螺旋和（2）L2环。在体外，这些区域的突变降低了RecA对PG和CL的亲和力。使用3D超分辨率显微镜，我们证明，depletingEscherichia coliPG和CL改变了RecA焦点的定位，阻碍了RecA丝束的形成。因此，缺乏aPL的大肠杆菌细胞在DNA损伤后不能启动强有力的SOS反应，表明膜充当用于使RecA丝束的形成成核的支架，并且在SOS反应中起重要作用。
We characterize the interaction of RecA with membranes in vivo and in vitro and demonstrate that RecA binds tightly to the anionic phospholipids cardiolipin (CL) and phosphatidylglycerol (PG). Using computational models, we identify two regions of RecA that interact with PG and CL: (1) the N-terminal helix and (2) loop L2. Mutating these regions decreased the affinity of RecA to PG and CL in vitro. Using 3D super-resolution microscopy, we demonstrate that depletingEscherichia coliPG and CL altered the localization of RecA foci and hindered the formation of RecA filament bundles. Consequently,E.colicells lacking aPLs fail to initiate a robust SOS response after DNA damage, indicating that the membrane acts as a scaffold for nucleating the formation of RecA filament bundles and plays an important role in the SOS response.