Reactome: A Curated Pathway Database

MAP2K1 phosphorylates MAPK3 (R-HSA-109860)

Species Homo sapiens


MAP2K1 (also known as MEK1) phosphorylates the critical Thr202 and Tyr204 on MAPK3 (ERK1), converting two ATP to ADP. Phosphorylation of MAPK3 activates its kinase activity.

MAP2K1 activation requires the phosphorylation of two serine residues (S218 and S222) in the activation loop.

Locations in the PathwayBrowser
Additional Information
Compartment cytosol
Components of this entry
Input entries
Output entries
Catalyst Activity
PhysicalEntity Activity Active Units
p-2S-MAP2K1:MAPK3 protein serine/threonine kinase activity (0004674)
Cross References
Database Identifier
IntAct IM-11690-5, IM-11690-9
This entry is regulated by
Regulation type Name
inhibition by phosphorylation