Reaction: MAP2K1 phosphorylates MAPK3

- in pathway: MAPK3 (ERK1) activation
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.

Reaction - small molecule participants:
ADP [cytosol]
ATP [cytosol]
ADP [cytosol]
ATP [cytosol]
Reactome.org reaction link: R-HSA-109860

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Reaction input - small molecules:
ATP(4-)
ChEBI:30616
ATP(4-)
ChEBI:30616
Reaction output - small molecules:
ADP(3-)
ChEBI:456216
ADP(3-)
ChEBI:456216
Reactome.org link: R-HSA-109860