c-Abl regulates early growth response protein (EGR1) in response to oxidative stress

Oncogene. 2005 Dec 8;24(55):8085-92. doi: 10.1038/sj.onc.1208953.

Abstract

c-Abl is a tyrosine kinase that can act as a regulator of cell growth and apoptosis in response to stress. Using cell lines expressing c-Abl in an inducible manner, we identified genes whose expression was regulated by c-Abl kinase activity. Microarray analysis indicated that Early Growth Response-1 (EGR1) gene expression is induced by c-Abl kinase activity, which was confirmed at the message and protein levels. Promoter mapping experiments revealed that c-Abl utilizes three distal serum response elements (SREs) in the EGR1 promoter, which are transactivated by mitogen/extracellular receptor kinase (MEK/ERK) signaling. PD 95089, a specific inhibitor of MEK/ERK signaling, attenuated c-Abl-mediated upregulation of EGR1 expression in a dose-dependent manner. Similar results were obtained by using a dominant-negative mutant of mitogen/extracellular kinase. Significantly, hydrogen peroxide-induced EGR1 expression appears to be mediated by c-Abl, as cells expressing dominant negative c-Abl, and c-Abl-/- murine embryonic fibroblasts, are completely defective in hydrogen peroxide-induced EGR1 expression. In addition, c-Abl-induced apoptosis is partially mitigated by EGR1 activity, as cells devoid of EGR1 expression undergo reduced rates of c-Abl-induced apoptosis. Together, these results indicate that c-Abl promotes the induction of EGR1 through the MEK/ERK pathway in regulating apoptotic response to oxidative stress.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Apoptosis
  • Cell Line
  • Early Growth Response Protein 1 / genetics*
  • Early Growth Response Protein 1 / metabolism
  • Fibroblasts / physiology
  • Gene Expression Regulation
  • Genes, Reporter
  • Humans
  • Hydrogen Peroxide / pharmacology
  • MAP Kinase Signaling System
  • Mice
  • Oligonucleotide Array Sequence Analysis
  • Oxidative Stress
  • Promoter Regions, Genetic
  • Proto-Oncogene Proteins c-abl / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Transfection

Substances

  • EGR1 protein, human
  • Early Growth Response Protein 1
  • Egr1 protein, mouse
  • Hydrogen Peroxide
  • Proto-Oncogene Proteins c-abl