primary messenger

ligand

second messenger

seven-transmembrane-helix (7TM) receptor

epinephrine

G protein

G_α

G_βγ

G-protein-coupled receptor (GCPR)

adenylate cyclase

protein kinase A (PKA)

phosphoinositide cascade

phospholipase C

receptor tyrosine kinase (RTK)

Ras

calmodulin (CaM)

EF hand

calmodulin-dependent protein (CaM) kinase

proto-oncogene

oncogene

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