The Aurora B specificity switch is required to protect from non-disjunction at the metaphase/anaphase transition

Nat Commun. 2020 Mar 13;11(1):1396. doi: 10.1038/s41467-020-15163-6.

Abstract

The Aurora B abscission checkpoint delays cytokinesis until resolution of DNA trapped in the cleavage furrow. This process involves PKCε phosphorylation of Aurora B S227. Assessing if this PKCε-Aurora B module provides a more widely exploited genome-protective control for the cell cycle, we show Aurora B phosphorylation at S227 by PKCε also occurs during mitosis. Expression of Aurora B S227A phenocopies inhibition of PKCε in by-passing the delay and resolution at anaphase entry that is associated with non-disjunction and catenation of sister chromatids. Implementation of this anaphase delay is reflected in PKCε activation following cell cycle dependent cleavage by caspase 7; knock-down of caspase 7 phenocopies PKCε loss, in a manner rescued by ectopically expressing/generating a free PKCε catalytic domain. Molecular dynamics indicates that Aurora B S227 phosphorylation induces conformational changes and this manifests in a profound switch in specificity towards S29 TopoIIα phosphorylation, a response necessary for catenation resolution during mitosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anaphase / genetics
  • Anaphase / physiology*
  • Aurora Kinase B / chemistry
  • Aurora Kinase B / genetics
  • Aurora Kinase B / metabolism*
  • Caspase 7 / metabolism
  • Cell Cycle Proteins / metabolism
  • Chromatids / metabolism
  • Chromatin
  • Chromosomes / metabolism
  • HEK293 Cells
  • Humans
  • Metaphase / genetics
  • Metaphase / physiology*
  • Mitosis / genetics
  • Mitosis / physiology*
  • Molecular Dynamics Simulation
  • Phosphorylation
  • Protein Kinase C-epsilon / metabolism
  • Recombinant Proteins
  • Signal Transduction / physiology

Substances

  • Cell Cycle Proteins
  • Chromatin
  • Recombinant Proteins
  • AURKB protein, human
  • Aurora Kinase B
  • Protein Kinase C-epsilon
  • Caspase 7