Chromosomal enrichment and activation of the aurora B pathway are coupled to spatially regulate spindle assembly. Academic Article uri icon

Overview

abstract

  • Chromatin-induced spindle assembly depends on regulation of microtubule-depolymerizing proteins by the chromosomal passenger complex (CPC), consisting of Incenp, Survivin, Dasra (Borealin), and the kinase Aurora B, but the mechanism and significance of the spatial regulation of Aurora B activity remain unclear. Here, we show that the Aurora B pathway is suppressed in the cytoplasm of Xenopus egg extract by phosphatases, but that it becomes activated by chromatin via a Ran-independent mechanism. While spindle microtubule assembly normally requires Dasra-dependent chromatin binding of the CPC, this function of Dasra can be bypassed by clustering Aurora B-Incenp by using anti-Incenp antibodies, which stimulate autoactivation among bound complexes. However, such chromatin-independent Aurora B pathway activation promotes centrosomal microtubule assembly and produces aberrant achromosomal spindle-like structures. We propose that chromosomal enrichment of the CPC results in local kinase autoactivation, a mechanism that contributes to the spatial regulation of spindle assembly and possibly to other mitotic processes.

publication date

  • January 1, 2007

Research

keywords

  • Chromosomes
  • Protein Serine-Threonine Kinases
  • Spindle Apparatus
  • Xenopus

Identity

PubMed Central ID

  • PMC1892535

Scopus Document Identifier

  • 33845783921

Digital Object Identifier (DOI)

  • 10.1016/j.devcel.2006.11.001

PubMed ID

  • 17199039

Additional Document Info

volume

  • 12

issue

  • 1