The extracellular signal-regulated kinase 3 (mitogen-activated protein kinase 6 [MAPK6])-MAPK-activated protein kinase 5 signaling complex regulates septin function and dendrite morphology

Mol Cell Biol. 2012 Jul;32(13):2467-78. doi: 10.1128/MCB.06633-11. Epub 2012 Apr 16.

Abstract

Mitogen-activated protein kinase-activated protein (MAPKAP) kinase 5 (MK5) deficiency is associated with reduced extracellular signal-regulated kinase 3 (ERK3) (mitogen-activated protein kinase 6) levels, hence we utilized the MK5 knockout mouse model to analyze the physiological functions of the ERK3/MK5 signaling module. MK5-deficient mice displayed impaired dendritic spine formation in mouse hippocampal neurons in vivo. We performed large-scale interaction screens to understand the neuronal functions of the ERK3/MK5 pathway and identified septin7 (Sept7) as a novel interacting partner of ERK3. ERK3/MK5/Sept7 form a ternary complex, which can phosphorylate the Sept7 regulators Binders of Rho GTPases (Borgs). In addition, the brain-specific nucleotide exchange factor kalirin-7 (Kal7) was identified as an MK5 interaction partner and substrate protein. In transfected primary neurons, Sept7-dependent dendrite development and spine formation are stimulated by the ERK3/MK5 module. Thus, the regulation of neuronal morphogenesis is proposed as the first physiological function of the ERK3/MK5 signaling module.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • DNA Primers / genetics
  • Dendrites / metabolism*
  • Dendrites / ultrastructure*
  • GTP-Binding Protein Regulators / metabolism
  • Guanine Nucleotide Exchange Factors / metabolism
  • HEK293 Cells
  • HeLa Cells
  • Hippocampus / cytology
  • Hippocampus / metabolism
  • Humans
  • Intracellular Signaling Peptides and Proteins / chemistry
  • Intracellular Signaling Peptides and Proteins / deficiency
  • Intracellular Signaling Peptides and Proteins / genetics
  • Intracellular Signaling Peptides and Proteins / metabolism*
  • MAP Kinase Signaling System
  • Mice
  • Mice, Knockout
  • Mitogen-Activated Protein Kinase 6 / chemistry
  • Mitogen-Activated Protein Kinase 6 / genetics
  • Mitogen-Activated Protein Kinase 6 / metabolism*
  • Models, Neurological
  • Multiprotein Complexes / chemistry
  • Multiprotein Complexes / metabolism
  • Neurogenesis / physiology
  • Neurons / metabolism
  • Neurons / ultrastructure
  • Protein Serine-Threonine Kinases / chemistry
  • Protein Serine-Threonine Kinases / deficiency
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism*
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Septins / chemistry
  • Septins / genetics
  • Septins / metabolism*
  • Transfection

Substances

  • DNA Primers
  • GTP-Binding Protein Regulators
  • Guanine Nucleotide Exchange Factors
  • Intracellular Signaling Peptides and Proteins
  • KALRN protein, mouse
  • Multiprotein Complexes
  • Recombinant Fusion Proteins
  • MAP-kinase-activated kinase 5
  • Protein Serine-Threonine Kinases
  • Mapk6 protein, mouse
  • Mitogen-Activated Protein Kinase 6
  • Sept7 protein, mouse
  • Septins