Dyrk kinases regulate phosphorylation of doublecortin, cytoskeletal organization, and neuronal morphology

Cytoskeleton (Hoboken). 2012 Jul;69(7):514-27. doi: 10.1002/cm.21021. Epub 2012 Mar 7.

Abstract

In a neuronal overexpression screen focused on kinases and phosphatases, one "hit" was the dual specificity tyrosine phosphorylation-regulated kinase (Dyrk4), which increased the number of dendritic branches in hippocampal neurons. Overexpression of various Dyrk family members in primary neurons significantly changed neuronal morphology. Dyrk1A decreased axon growth, Dyrk3 and Dyrk4 increased dendritic branching, and Dyrk2 decreased both axon and dendrite growth and branching. Kinase-deficient mutants revealed that most of these effects depend on kinase activity. Because doublecortin (DCX), a microtubule-binding protein, regulates cytoskeletal dynamics and neuronal morphogenesis, we investigated the possibility that DCX is a target of Dyrks. We found that overexpression of Dyrk2 and Dyrk3, but not Dyrk1A or Dyrk4, can change DCX phosphorylation status. Mutation of a consensus phosphorylation site for Dyrk kinases at Serine 306 (Ser306) in DCX indicated that this is one target site for Dyrk2 and Dyrk3. Overexpression of Dyrk2 restored altered DCX distribution in the growth cones of dendrites and axons, and partially reversed the morphological effects of DCX overexpression; some of these effects were abrogated by mutation of Ser306 to alanine. These studies implicate Dyrks in the regulation of cytoskeletal organization and process outgrowth in neurons, and suggest that DCX is one relevant Dyrk target.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cell Line
  • Cells, Cultured
  • Cytoskeleton / chemistry
  • Cytoskeleton / metabolism*
  • Doublecortin Protein
  • Doublecortin-Like Kinases
  • Gene Expression
  • Hippocampus / metabolism
  • Humans
  • Intracellular Signaling Peptides and Proteins / metabolism*
  • Mice
  • Microscopy, Confocal
  • Molecular Sequence Data
  • Mutation
  • Neurons / cytology*
  • Neurons / enzymology*
  • Phosphorylation
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism*
  • Protein Transport
  • Protein-Tyrosine Kinases / genetics
  • Protein-Tyrosine Kinases / metabolism*
  • Rats
  • Sequence Alignment

Substances

  • Dcx protein, mouse
  • Dcx protein, rat
  • Doublecortin Protein
  • Intracellular Signaling Peptides and Proteins
  • Dyrk kinase
  • DCLK1 protein, human
  • Doublecortin-Like Kinases
  • Protein-Tyrosine Kinases
  • Protein Serine-Threonine Kinases