NuMA mechanically reinforces the spindle independently of its partner dynein.

ABSTRACT: Both motor and non-motor proteins organize microtubules to build the spindle and maintain it against opposing forces. NuMA, a long microtubule binding protein, is essential to spindle structure and function. NuMA recruits the motor dynein to spindle microtubule minus-ends to actively cluster them, but whether NuMA performs other spindle roles remains unknown. Here, we show that NuMA acts independently of dynein to passively reinforce the mammalian spindle. NuMA that cannot bind dynein is sufficient to protect spindle poles against fracture under external force. In contrast, NuMA with a shorter coiled-coil or disrupted self-interactions cannot protect spindle poles, and NuMA turnover differences cannot explain mechanical differences. In vitro, NuMA's C-terminus self-interacts and bun

SUBMITTER: Cho NH 

PROVIDER: S-EPMC12309564 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature