Spatial positioning of EB family proteins at microtubule tips involves distinct nucleotide-dependent binding properties.
Spatial positioning of EB family proteins at microtubule tips involves distinct nucleotide-dependent binding properties.
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EB家族蛋白在微管尖端的空间定位涉及不同的核苷酸依赖性结合特性。
DOI：
10.1242/jcs.219550
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发表时间：
2018-10-31
影响因子：
4
通讯作者：
Straube A
中科院分区：
文献类型：
--
作者：
Roth D;Fitton BP;Chmel NP;Wasiluk N;Straube A
EB蛋白跟踪生长的微管末端，并直接或通过充当尖端跟踪网络的枢纽来调节微管动力学。哺乳动物细胞表达具有不同细胞作用的三种EB蛋白的细胞类型特异性组合。在这里，我们重建了EB1， EB2和EB3尖端的体外跟踪。我们发现，这三种电子离子在微管尖端都表现出快速的交换，并且它们的信号与微管组装速率有关。然而，这三种信号在微管尖端的最大值和位置上有所不同。利用核苷酸类似物构建的微管和定点诱变，我们发现EB2更倾向于与含有不同核苷酸的1:1混合物的微管晶格结合，其独特的结合特异性是通过在EB微管结合域与微管蛋白的右侧界面上的氨基酸取代而赋予的。我们的数据与模型一致，即所有三个EB副物都能感知其结合位点两侧的β-微管蛋白的核苷酸状态。它们不同的首选结合位点有助于在时间进化的微管尖端结构中占据空间上不同的区域。摘要：用EB1、EB2和EB3体外重建尖端跟踪表明，这三种蛋白可以感知其结合位点两侧的β-微管蛋白的核苷酸状态。
EB proteins track the ends of growing microtubules and regulate microtubule dynamics both directly and by acting as the hub of the tip-tracking network. Mammalian cells express cell type-specific combinations of three EB proteins with different cellular roles. Here, we reconstitute EB1, EB2 and EB3 tip tracking in vitro. We find that all three EBs show rapid exchange at the microtubule tip and that their signal correlates to the microtubule assembly rate. However, the three signals differ in their maxima and position from the microtubule tip. Using microtubules built with nucleotide analogues and site-directed mutagenesis, we show that EB2 prefers binding to microtubule lattices containing a 1:1 mixture of different nucleotides and its distinct binding specificity is conferred by amino acid substitutions at the right-hand-side interface of the EB microtubule-binding domain with tubulin. Our data are consistent with the model that all three EB paralogues sense the nucleotide state of both β-tubulins flanking their binding site. Their different profile of preferred binding sites contributes to occupying spatially distinct domains at the temporally evolving microtubule tip structure. Summary: In vitro reconstitution of tip tracking with EB1, EB2 and EB3 shows that these three proteins sense the nucleotide state of both β-tubulins flanking their binding site.
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影响因子：
3.3
作者：
HYMAN, AA;SALSER, S;MITCHISON, TJ
通讯作者：
MITCHISON, TJ
DOI：
10.1007/978-1-61779-252-6_2
发表时间：
2011-01-01
期刊：
MICROTUBE DYNAMICS: METHODS AND PROTOCOLS
影响因子：
--
作者：
Gell, Christopher;Friel, Claire T.;Howard, Jonathon
通讯作者：
Howard, Jonathon
高分辨率微管结构揭示了 GTP 水解后 αβ-微管蛋白的结构转变。
影响因子：
64.5
作者：
Alushin GM;Lander GC;Kellogg EH;Zhang R;Baker D;Nogales E
通讯作者：
Nogales E
影响因子：
7.7
作者：
Geyer EA;Burns A;Lalonde BA;Ye X;Piedra FA;Huffaker TC;Rice LM
通讯作者：
Rice LM
影响因子：
64.5
作者：
Honnappa, Srinivas;Gouveia, Susana Montenegro;Steinmetz, Michel O.
通讯作者：
Steinmetz, Michel O.