Bistability of a coupled Aurora B kinase-phosphatase system in cell division

Elife. 2016 Jan 14;5:e10644. doi: 10.7554/eLife.10644.

Abstract

Aurora B kinase, a key regulator of cell division, localizes to specific cellular locations, but the regulatory mechanisms responsible for phosphorylation of substrates located remotely from kinase enrichment sites are unclear. Here, we provide evidence that this activity at a distance depends on both sites of high kinase concentration and the bistability of a coupled kinase-phosphatase system. We reconstitute this bistable behavior and hysteresis using purified components to reveal co-existence of distinct high and low Aurora B activity states, sustained by a two-component kinase autoactivation mechanism. Furthermore, we demonstrate these non-linear regimes in live cells using a FRET-based phosphorylation sensor, and provide a mechanistic theoretical model for spatial regulation of Aurora B phosphorylation. We propose that bistability of an Aurora B-phosphatase system underlies formation of spatial phosphorylation patterns, which are generated and spread from sites of kinase autoactivation, thereby regulating cell division.

Keywords: cell biology; computational biology; enzyme kinetics; human; kinetochore; mathematical modeling; mitosis; phosphorylation; spatio-temporal dynamics; systems biology.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aurora Kinase B / metabolism*
  • Cell Cycle Proteins / metabolism
  • Cell Division*
  • Centromere / metabolism
  • Epithelial Cells / enzymology*
  • Epithelial Cells / physiology*
  • HeLa Cells
  • Humans
  • Microscopy
  • Microtubules / metabolism
  • Optical Imaging
  • Phosphoric Monoester Hydrolases / metabolism*
  • Spindle Apparatus / metabolism

Substances

  • Cell Cycle Proteins
  • Aurora Kinase B
  • Phosphoric Monoester Hydrolases