BIOGRID CURATED DATA FOR PUBLICATION: CM1-driven assembly and activation of yeast ?-tubulin small complex underlies microtubule nucleation.

Protein-Protein, Genetic, and Chemical Interactions for Brilot AF (2021):CM1-driven assembly and activation of yeast ?-tubulin small complex underlies microtubule nucleation. curated by BioGRID (https://thebiogrid.org); ABSTRACT: Microtubule (MT) nucleation is regulated by the ?-tubulin ring complex (?TuRC), conserved from yeast to humans. In Saccharomyces cerevisiae, ?TuRC is composed of seven identical ?-tubulin small complex (?TuSC) sub-assemblies, which associate helically to template MT growth. ?TuRC assembly provides a key point of regulation for the MT cytoskeleton. Here, we combine crosslinking mass spectrometry, X-ray crystallography, and cryo-EM structures of both monomeric and dimeric ?TuSCs, and open and closed helical ?TuRC assemblies in complex with Spc110p to elucidate the mechanisms of ?TuRC assembly. ?TuRC assembly is substantially aided by the evolutionarily conserved CM1 motif in Spc110p spanning a pair of adjacent ?TuSCs. By providing the highest resolution and most complete views of any ?TuSC assembly, our structures allow phosphorylation sites to be mapped, surprisingly suggesting that they are mostly inhibitory. A comparison of our structures with the CM1 binding site in the human ?TuRC structure at the interface between GCP2 and GCP6 allows for the interpretation of significant structural changes arising from CM1 helix binding to metazoan ?TuRC.

蛋白质-蛋白质、遗传和化学相互作用数据集，针对 Brilot AF（2021）的研究：由 CM1 驱动的酵母 ?-微管小复合物的组装与激活，基于 MT 核化过程，由 BioGRID（https://thebiogrid.org）整理；摘要：微管（MT）的核化过程受 ?-微管蛋白环复合物（?TuRC）的调控，该复合物在酵母到人类的进化过程中得以保留。在酿酒酵母中，?TuRC 由七个相同的 ?-微管蛋白小复合物（?TuSC）亚复合物组成，这些亚复合物螺旋状地结合以模板微管生长。?TuRC 的组装为微管细胞骨架提供了一个关键的调控点。本研究中，我们结合了交联质谱、X射线晶体学和冷冻电子显微镜结构，分析了单体和二聚体 ?TuSCs，以及开放和封闭的螺旋状 ?TuRC 组装与 Spc110p 结合的情况，以阐明 ?TuRC 组装的机制。?TuRC 的组装在很大程度上得益于 Spc110p 中的进化保守的 CM1 模式，该模式跨越相邻的两个 ?TuSCs。通过提供任何 ?TuSC 组装的最高分辨率和最完整的视图，我们的结构允许映射磷酸化位点，出人意料地表明它们主要是抑制性的。将我们的结构与人类 ?TuRC 结构中 GCP2 和 GCP6 接界处的 CM1 结合位点进行比较，有助于解释由 CM1 螺旋与多细胞生物 ?TuRC 结合所引起的显著结构变化。