The Arabidopsis SPIRAL2 Protein Targets and Stabilizes Microtubule Minus Ends.
The Arabidopsis SPIRAL2 Protein Targets and Stabilizes Microtubule Minus Ends.
复制标题
DOI：
10.1016/j.cub.2018.02.014
复制
发表时间：
2018-03-19
期刊：
影响因子：
--
通讯作者：
Dixit R
中科院分区：
文献类型：
--
作者：
Fan Y;Burkart GM;Dixit R
微管尖端动力学对植物微管阵列组装和功能的贡献仍然知之甚少。在这里，我们报告说，拟南芥SPIRAL 2（SPR 2）蛋白质调制的动力学的acentrosomal皮质微管正，负结束在一个相反的方式。功能性SPR 2-mRuby融合蛋白的实时成像显示，SPR 2除了在微管交叉点和沿着晶格定位之外，还显示微管正末端和负末端追踪活性。微管动力学分析表明，皮质微管加端很少经历灾难相比，野生型在spr 2 -2敲除突变体。相反，皮质微管负末端在spr 2 -2解聚的速度比野生型快得多。spr 2 -2负末端的失稳导致微管交叉寿命的显著降低，这显著降低了微管切断频率并抑制了光诱导的微管阵列重定向。使用体外重建实验结合单分子成像，我们发现，重组SPR 2-GFP固有地定位于微管负端，在那里它稳定地结合并抑制它们的动力学。总之，我们的数据建立了SPR 2作为一种新型的微管尖端调节器，控制微管的长度和寿命。
The contribution of microtubule tip dynamics to the assembly and function of plant microtubule arrays remains poorly understood. Here, we report that the Arabidopsis SPIRAL2 (SPR2) protein modulates the dynamics of the acentrosomal cortical microtubule plus- and minus-ends in an opposing manner. Live imaging of a functional SPR2-mRuby fusion protein revealed that SPR2 shows both microtubule plus- and minus-end tracking activity in addition to localization at microtubule intersections and along the lattice. Analysis of microtubule dynamics showed that cortical microtubule plus-ends rarely undergo catastrophe in the spr2-2 knockout mutant compared to wild-type. In contrast, cortical microtubule minus-ends in spr2-2 depolymerized at a much faster rate than in wild-type. Destabilization of the minus-ends in spr2-2 caused a significant decrease in the lifetime of microtubule crossovers, which dramatically reduced the microtubule severing frequency and inhibited light-induced microtubule array reorientation. Using in vitro reconstitution experiments combined with single-molecule imaging, we found that recombinant SPR2-GFP intrinsically localizes to microtubule minus-ends where it binds stably and inhibits their dynamics. Together, our data establish SPR2 as a new type of microtubule tip regulator that governs the length and lifetime of microtubules.
登录
查看更多内容
影响因子：
56.9
作者：
Shaw, SL;Kamyar, R;Ehrhardt, DW
通讯作者：
Ehrhardt, DW
影响因子：
11.8
作者：
Jiang, Kai;Hua, Shasha;Akhmanova, Anna
通讯作者：
Akhmanova, Anna
DOI：
10.1073/pnas.1404133111
发表时间：
2014-04-22
影响因子：
11.1
作者：
Hendershott, Melissa C.;Vale, Ronald D.
通讯作者：
Vale, Ronald D.
DOI：
10.1073/pnas.1218017109
发表时间：
2012-12-04
影响因子：
11.1
作者：
Tanaka, Nobutoshi;Meng, Wenxiang;Takeichi, Masatoshi
通讯作者：
Takeichi, Masatoshi
影响因子：
8.8
作者：
Chuang M;Goncharov A;Wang S;Oegema K;Jin Y;Chisholm AD
通讯作者：
Chisholm AD