Reactome: A Curated Pathway Database

Prolonged ERK activation events (R-HSA-169893)

Species Homo sapiens


After NGF binding, activated Trk receptors provide multiple docking sites for adaptor proteins and enzymes. Two docking proteins, the Ankyrin-Rich Membrane Spanning protein (ARMS/Kidins220) and Fibroblast growth factor receptor substrate 2 (Frs2), target signaling molecules in response to NGF stimulation and link receptor activation with the MAP kinase (also called the Extracellular signal-Regulated Kinase cascade, ERK) cascade, an essential process for growth factor-induced cell proliferation and differentiation.
A feature of NGF signaling is the sustained activation of the MAPK cascade. This is achieved by the small G protein, Rap1 which binds to and activates B-Raf, an activator of the MAPK cascade. Rap1 is a member of the Ras family of G proteins and like all G proteins, Rap1 is in an inactive state when bound to GDP and is active when bound to GTP. A specific GEF (guanine nucleotide exchange factor) called C3G can activate Rap1 by exchanging GDP for GTP.

Locations in the PathwayBrowser
Additional Information
GO Biological Process activation of MAPKK activity (0000186)
Literature References
pubMedId Title Journal Year
12765839 Does Rap1 deserve a bad Rap? Trends Biochem Sci 2003
9069267 Signal transduction by the neurotrophin receptors Curr Opin Cell Biol 1997