Differential Effects of cAMP in Neurons and Astrocytes

L. Dugan,Joanna S. Kim,Yujing Zhang,R. Bart,Yuling Sun,D. Holtzman,D. Gutmann

Published 1999 in Journal of Biological Chemistry

ABSTRACT

Mitogen-activated protein kinase (MAPK) activation provides cell type-specific signals important for cellular differentiation, proliferation, and survival. Cyclic AMP (cAMP) has divergent effects on MAPK activity depending on whether signaling is through Ras/Raf-1 or Rap1/B-raf. We found that central nervous system-derived neurons, but not astrocytes, express B-raf. In neurons, cAMP activated MAPK in a Rap1/B-raf-dependent manner, while in astrocytes, cAMP decreased MAPK activity. Inhibition of MAPK in neurons decreased neuronal growth factor-mediated survival, and activation of MAPK by cAMP analogues rescued neurons from death. Furthermore, constitutive expression of B-raf in astrocytoma cells increased MAPK activation, as seen in neurons, and enhanced proliferation. These data provide the first experimental evidence that B-raf is the molecular switch which dominantly permits differential cAMP-dependent regulation of MAPK in neuronsversus astrocytes, with important implications for both survival and proliferation.

PUBLICATION RECORD

CITATION MAP

EXTRACTION MAP

CLAIMS

  • No claims are published for this paper.

CONCEPTS

  • No concepts are published for this paper.

REFERENCES

Showing 1-44 of 44 references · Page 1 of 1

CITED BY

Showing 1-100 of 244 citing papers · Page 1 of 3