GSK-3 mediates the okadaic acid-induced modification of collapsin response mediator protein-2 in human SK-N-SH neuroblastoma cells

J Cell Biochem. 2008 Apr 15;103(6):1833-48. doi: 10.1002/jcb.21575.


Collapsin response mediator protein-2 (CRMP-2), a phosphoprotein involved in axonal outgrowth and microtubule dynamics, is aberrantly phosphorylated in Alzheimer's disease (AD) brain. Alteration of glycogen synthase kinase-3 (GSK-3) activity is associated with the pathogenesis of AD. Here, we show that CRMP-2 is one of the major substrates for GSK-3 in pig brain extracts. Both GSK-3alpha and 3beta phosphorylate purified pig brain CRMP-2 and significantly alter its mobility in SDS-gels, resembling the CRMP-2 modification observed in AD brain. Interestingly, this modification can be detected in SK-N-SH neuroblastoma cells treated with a phosphatase inhibitor, okadaic acid (OA), and GSK-3 inhibitors completely block this OA-induced event. Knockdown of both GSK-3alpha and 3beta, but not either kinase alone, impairs OA-induced modification of CRMP-2. Mutation of Ser-518 or Ser-522 of CRMP-2, which are highly phosphorylated in AD brain, to Ala blocks the OA-induced modification of CRMP-2 in SK-N-SH cells. Ser-522 prephosphorylated by Cdk5 is required for subsequent GSK-3alpha-mediated phosphorylation of CRMP-2 in vitro. Collectively, our results demonstrate for the first time that OA can induce phosphorylation of CRMP-2 in SK-N-SH cells at sites aberrantly phosphorylated in AD brain, and both GSK-3alpha and 3beta and Ser-522 kinase(s) are involved in this process.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alzheimer Disease / metabolism
  • Animals
  • Brain / metabolism
  • Cell Line, Tumor
  • Cyclin-Dependent Kinase 5 / metabolism
  • Glycogen Synthase Kinase 3 / antagonists & inhibitors
  • Glycogen Synthase Kinase 3 / genetics
  • Glycogen Synthase Kinase 3 / metabolism*
  • Glycogen Synthase Kinase 3 beta
  • Humans
  • Intercellular Signaling Peptides and Proteins / genetics
  • Intercellular Signaling Peptides and Proteins / physiology*
  • Isoenzymes / antagonists & inhibitors
  • Isoenzymes / genetics
  • Isoenzymes / metabolism
  • Mutation
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / physiology*
  • Neuroblastoma
  • Okadaic Acid / pharmacology*
  • Phosphoric Monoester Hydrolases / antagonists & inhibitors
  • Phosphorylation
  • Signal Transduction
  • Swine
  • Tissue Extracts / metabolism


  • Intercellular Signaling Peptides and Proteins
  • Isoenzymes
  • Nerve Tissue Proteins
  • Tissue Extracts
  • collapsin response mediator protein-2
  • Okadaic Acid
  • Cyclin-Dependent Kinase 5
  • Glycogen Synthase Kinase 3 beta
  • Glycogen Synthase Kinase 3
  • glycogen synthase kinase 3 alpha
  • Phosphoric Monoester Hydrolases