Using kinomics to delineate signaling pathways: control of CRTC2/TORC2 by the AMPK family

Cell Cycle. 2008 Dec 15;7(24):3823-8. doi: 10.4161/cc.7.24.7241. Epub 2008 Dec 21.

Abstract

The classical role of AMP-activated protein kinase (AMPK) as an energy status sensor is expanding to include other members of the AMPK family. Recent genetic and cell biological evidence points to a role for MAP/microtubule affinity-regulating kinase 2 (MARK2/EMK/Par1b) in the regulation of metabolic events as well as in the control of CREB-dependent transcription activated by glucose in pancreatic islet beta cells. We have recently developed an in vitro kinase screening platform to identify novel kinase:substrate pairs, the building blocks of signal transduction pathways. Application of this technology led us to identify MARK2 as the kinase that targets a novel glucose-regulated phosphorylation site on Transducer of Regulated CREB Activity 2 (TORC2, referred to as CREB-Regulated Transcriptional Coactivator 2, or CRTC2), a transcriptional coactivator essential for CREB activity in beta cells. We discuss these recent developments and suggest a model whereby members of the AMPK family integrate numerous signals to coordinate energy metabolism and cellular polarity with gene expression to regulate cell function/proliferation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AMP-Activated Protein Kinases / metabolism*
  • Cell Line
  • Cyclic AMP Response Element-Binding Protein / genetics
  • Cyclic AMP Response Element-Binding Protein / metabolism
  • Humans
  • Islets of Langerhans / physiology
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism
  • Signal Transduction*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*

Substances

  • CRTC2 protein, human
  • Cyclic AMP Response Element-Binding Protein
  • Transcription Factors
  • MARK2 protein, human
  • Protein Serine-Threonine Kinases
  • AMP-Activated Protein Kinases