Depletion of IK causes mitotic arrest through aberrant regulation of mitotic kinases and phosphatases

FEBS Lett. 2014 Aug 25;588(17):2844-50. doi: 10.1016/j.febslet.2014.06.046. Epub 2014 Jul 1.

Abstract

IK is known to inhibit the expression of major histocompatibility complex (MHC) class II antigen, but other cellular functions of IK remain to be uncovered. In this study, IK depletion caused misalignment of chromosomes through an increase in Aurora A and PLK1 phosphorylation, which was mediated by a decrease in PP1 and PP2A activities. On the other hand, the treatment of a dual inhibitor against CDK and Aurora kinases overrode IK depletion-induced mitotic arrest through the activation of phosphatase activity. These findings imply that IK is an essential protein for achieving correct mitotic progress through the regulation of mitotic kinases and phosphatases.

Keywords: Aurora A; CDK1; IK; Mitotic arrest; Protein phosphatase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis
  • Aurora Kinase A / metabolism*
  • Base Sequence
  • CDC2 Protein Kinase / metabolism
  • Cell Cycle Checkpoints*
  • Cell Cycle Proteins / metabolism
  • Cell Line
  • Cytokines / deficiency*
  • Cytokines / genetics
  • Cytokines / metabolism
  • Gene Silencing
  • Humans
  • Mice
  • Mitosis*
  • Phosphoprotein Phosphatases / antagonists & inhibitors
  • Phosphoprotein Phosphatases / metabolism*
  • Phosphorylation
  • Polo-Like Kinase 1
  • Protein Serine-Threonine Kinases / metabolism
  • Proto-Oncogene Proteins / metabolism
  • RNA, Small Interfering / genetics

Substances

  • Cell Cycle Proteins
  • Cytokines
  • IK protein, human
  • Ik protein, mouse
  • Proto-Oncogene Proteins
  • RNA, Small Interfering
  • Aurora Kinase A
  • Protein Serine-Threonine Kinases
  • CDC2 Protein Kinase
  • Phosphoprotein Phosphatases