How Microtubules Build the Spindle Branch by Branch

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 newMTs 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.

Automated summary

The microtubule cytoskeleton is crucial for intracellular organization and regulated motion. Branching microtubule nucleation is a key pathway for generating microtubules, and recent research has focused on characterizing the factors and regulation involved in this process, as well as its implications in human disease.