Interaction of chromatin-associated Plk1 and Mcm7

J Biol Chem. 2005 Mar 25;280(12):11943-7. doi: 10.1074/jbc.M413514200. Epub 2005 Jan 15.

Abstract

Plk1 is a multifunctional protein kinase involved in regulation of mitotic entry, chromosome segregation, centrosome maturation, and mitotic exit. Plk1 is a target of DNA damage checkpoints and aids resumption of the cell cycle during recovery from G2 arrest. The polo-box domain (PBD) of Plk1 interacts with phosphoproteins and localizes Plk1 to some mitotic structures. In a search for proteins that interact with the PBD of Plk1, we identified two of the minichromosome maintenance (MCM) proteins, Mcm2 and Mcm7. Co-immunoprecipitation and immunoblot analysis showed an interaction between full-length Plk1 and all other members of the MCM2-7 protein complex. Endogenous Plk1 co-immunoprecipitates with basal forms of Mcm7 as well as with slower migrating forms of Mcm7, induced in response to DNA damage. The strongest interaction between endogenous Plk1 and Mcm7 was detected in a soluble chromatin fraction. These findings suggest a new function for Plk1 in coordination of DNA replication and mitotic events.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Cell Cycle Proteins / chemistry*
  • Cell Cycle Proteins / physiology
  • Cells, Cultured
  • Chromatin / chemistry
  • DNA Damage
  • DNA Replication
  • DNA-Binding Proteins / chemistry*
  • DNA-Binding Proteins / physiology
  • Humans
  • Immunoprecipitation
  • Minichromosome Maintenance Complex Component 3
  • Minichromosome Maintenance Complex Component 7
  • Mitosis
  • Nuclear Proteins / chemistry*
  • Nuclear Proteins / physiology
  • Phosphorylation
  • Polo-Like Kinase 1
  • Protein Kinases / chemistry*
  • Protein Kinases / physiology
  • Protein Serine-Threonine Kinases
  • Proto-Oncogene Proteins
  • Transcription Factors / chemistry

Substances

  • Cell Cycle Proteins
  • Chromatin
  • DNA-Binding Proteins
  • MCM3 protein, human
  • Nuclear Proteins
  • Proto-Oncogene Proteins
  • Transcription Factors
  • Protein Kinases
  • Protein Serine-Threonine Kinases
  • MCM7 protein, human
  • Minichromosome Maintenance Complex Component 3
  • Minichromosome Maintenance Complex Component 7