Cooperation between Rho-GEF Gef2 and its binding partner Nod1 in the regulation of fission yeast cytokinesis.
Cooperation between Rho-GEF Gef2 and its binding partner Nod1 in the regulation of fission yeast cytokinesis.
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DOI：
10.1091/mbc.e13-06-0301
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发表时间：
2013-10
影响因子：
3.3
通讯作者：
Wu JQ
中科院分区：
文献类型：
--
作者：
Zhu YH;Ye Y;Wu Z;Wu JQ
以往的研究结果表明，在分裂酵母的早期胞质分裂过程中，推测的Rho-gef Gef2调控分裂位点的定位。这里，Nod1被确定为Gef2的结合伙伴。这两种蛋白质形成一个复合体，调节分裂部位的定位和收缩环的维持。此外，Gef2在体外与GTP酶Rho1、Rho4和Rho5结合。胞质分裂是细胞分裂周期的最后一步，它需要精确的空间和时间调节来确保遗传稳定性。Rho鸟嘌呤核苷酸交换因子(Rho GEF)和Rho GTP酶是胞质分裂的关键调节因子。我们先前发现，推测的Rho-gef Gef2与Polo Kinase Plo1配位，以控制裂解酵母中类苯丙素类蛋白MID1的皮质中层定位。在这里，我们显示了一个接头蛋白，Nod1，与Gef2共存于收缩环及其前体皮质节点。与Gef2∆一样，Nod1∆与参与分裂位点定位的各种胞质分裂突变体具有很强的遗传相互作用，提示Nod1在早期胞质分裂中发挥作用。我们发现Nod1和Gef2通过C-末端相互作用，这对它们的定位很重要。Nod1和Gef2的收缩环定位还依赖于Nod1和F-bar蛋白CDc15之间的相互作用，其中Nod1/Gef2复合体在收缩环维持中发挥作用，并影响分隔起始网络。此外，Gef2在体外可与纯化的GTP酶Rho1、Rho4和Rho5结合。综上所述，我们的数据表明，Nod1和Gef2在一个蛋白质复合体中协同作用，调节分裂酵母的胞质分裂。
Previous results showed that putative Rho-GEF Gef2 regulates division-site positioning during early cytokinesis in fission yeast. Here Nod1 is identified as a binding partner of Gef2. The two proteins form a complex to regulate division-site positioning and contractile-ring maintenance. In addition, Gef2 binds to GTPases Rho1, Rho4, and Rho5 in vitro. Cytokinesis is the last step of the cell-division cycle, which requires precise spatial and temporal regulation to ensure genetic stability. Rho guanine nucleotide exchange factors (Rho GEFs) and Rho GTPases are among the key regulators of cytokinesis. We previously found that putative Rho-GEF Gef2 coordinates with Polo kinase Plo1 to control the medial cortical localization of anillin-like protein Mid1 in fission yeast. Here we show that an adaptor protein, Nod1, colocalizes with Gef2 in the contractile ring and its precursor cortical nodes. Like gef2∆, nod1∆ has strong genetic interactions with various cytokinesis mutants involved in division-site positioning, suggesting a role of Nod1 in early cytokinesis. We find that Nod1 and Gef2 interact through the C-termini, which is important for their localization. The contractile-ring localization of Nod1 and Gef2 also depends on the interaction between Nod1 and the F-BAR protein Cdc15, where the Nod1/Gef2 complex plays a role in contractile-ring maintenance and affects the septation initiation network. Moreover, Gef2 binds to purified GTPases Rho1, Rho4, and Rho5 in vitro. Taken together, our data indicate that Nod1 and Gef2 function cooperatively in a protein complex to regulate fission yeast cytokinesis.