Raf-1 forms a stable complex with Mek1 and activates Mek1 by serine phosphorylation.
AUTOR(ES)
Huang, W
RESUMO
Recombinant Mek1 and Raf-1 proteins produced in Sf9 cells undergo a tight association both in vivo and in vitro, which apparently does not depend on additional factors or the kinase activity of Mek1 or Raf-1. The complex can be disrupted by two polyclonal antibodies raised against Raf-1 peptides. Coinfection with Raf-1 activates Mek1 > 150-fold, and coinfection with Raf-1 and Mek1 activates Erk1 approximately 90-fold. The activation of Mek1 by Raf-1 involves only serine phosphorylation, which is directly proportional to the extent of Mek1 activation. Phosphopeptide maps suggest a single Raf-1 phosphorylation site on mek1.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=47898Documentos Relacionados
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