In vitro effects on microtubule dynamics of purified Xenopus M phase-activated MAP kinase

Nature. 1991 Jan 17;349(6306):251-4. doi: 10.1038/349251a0.


The protein kinase MAP kinase, also called MAP2 kinase, is a serine/threonine kinase whose activation and phosphorylation are induced by a variety of mitogens, and which is thought to have a critical role in a network of protein kinases in mitogenic signal transduction. A burst in kinase activation and protein phosphorylation may also be important in triggering the dramatic reorganization of the cell during the transition from interphase to mitosis. The interphase-metaphase transition of microtubule arrays is under the control of p34cdc2 kinase, a central control element in the G2-M transition of the cell cycle. Here we show that a Xenopus kinase, closely related to the mitogen-activated mammalian MAP kinase, is phosphorylated and activated during M phase of meiotic and mitotic cell cycles, and that the interphase-metaphase transition of microtubule arrays can be induced by the addition of purified Xenopus M phase-activated MAP kinase or mammalian mitogen-activated MAP kinase to interphase extracts in vitro.

MeSH terms

  • Animals
  • Calcium-Calmodulin-Dependent Protein Kinases
  • Enzyme Activation
  • Interphase / physiology
  • Meiosis / physiology
  • Microtubule-Associated Proteins / metabolism
  • Microtubules / metabolism*
  • Mitosis / physiology*
  • Molecular Weight
  • Myelin Basic Protein / metabolism
  • Oocytes / drug effects
  • Oocytes / physiology
  • Phosphorylation
  • Progesterone / pharmacology
  • Protein Kinases / isolation & purification
  • Protein Kinases / metabolism
  • Protein Kinases / physiology*
  • Xenopus / metabolism*


  • Microtubule-Associated Proteins
  • Myelin Basic Protein
  • Progesterone
  • Protein Kinases
  • Calcium-Calmodulin-Dependent Protein Kinases