Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA; email:
Annu Rev Cell Dev Biol. 2022 Oct 6;38:1-23. doi: 10.1146/annurev-cellbio-120420-114559. Epub 2022 Jun 27.
The microtubule (MT) cytoskeleton provides the architecture that governs intracellular organization and the regulated motion of macromolecules through the crowded cytoplasm. The key to establishing a functioning cytoskeletal architecture is regulating when and where new MTs are nucleated. Within the spindle, the vast majority of MTs are generated through a pathway known as branching MT nucleation, which exponentially amplifies MT number in a polar manner. Whereas other MT nucleation pathways generally require a complex organelle such as the centrosome or Golgi apparatus to localize nucleation factors, the branching site is based solely on a simple, preformed MT, making it an ideal system to study MT nucleation. In this review, we address recent developments in characterizing branching factors, the branching reaction, and its regulation, as well as branching MT nucleation in systems beyond the spindle and within human disease.
微管（MT）细胞骨架提供了控制细胞内组织和大分子通过拥挤细胞质的调节运动的架构。建立功能细胞骨架架构的关键是调节新的 MT 在何处以及何时成核。在纺锤体中，绝大多数 MT 是通过一种称为分支 MT 成核的途径产生的，这种途径以极性方式指数扩增 MT 的数量。虽然其他 MT 成核途径通常需要一个复杂的细胞器，如中心体或高尔基体，以定位成核因子，但分支位点仅基于一个简单的、预先形成的 MT，使其成为研究 MT 成核的理想系统。在这篇综述中，我们讨论了描述分支因子、分支反应及其调控以及纺锤体以外和人类疾病内分支 MT 成核的最新进展。
