Raf-1 without MEK?
The Ras-Raf-MEK [(mitogen-activated protein kinase (MAPK) or extracellular signal-regulated kinase (ERK) kinase]-MAPK signaling pathway controls the activation of many cellular functions. Recent reports of Raf-1-deficient mice have indicated that MEK may not be an important downstream substrate for Raf-1 and that, in fact, Raf-1 is important for blocking apoptosis rather than for cell proliferation. Murakami and Morrison examine these recent findings and discuss their implications, as well as other possible conclusions that may be drawn from the published data.
Murakami
M S
MS
Regulation of Cell Growth Laboratory, National Cancer Institute, Frederick Cancer Research and Development Center, Frederick, MD 21702, USA. morrisod@nciaxp.ncifcrf.gov
Morrison
D K
DK
D000818:Animals; D002478:Cells, Cultured; D004622:Embryo, Mammalian / Q000502:physiology; D005314:Embryonic and Fetal Development; D048369:MAP Kinase Kinase 1; D048370:MAP Kinase Kinase 2; D020935:MAP Kinase Signaling System; D051379:Mice; D018345:Mice, Knockout; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism*; D008954:Models, Biological; D010641:Phenotype; D017354:Point Mutation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D019908:Proto-Oncogene Proteins c-raf / Q000235:genetics / Q000502:physiology*
D011505:Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D019908:Proto-Oncogene Proteins c-raf; D048369:MAP Kinase Kinase 1; D048370:MAP Kinase Kinase 2; C482127:Map2k1 protein, mouse; D020929:Mitogen-Activated Protein Kinase Kinases