G protein–coupled receptors (
GPCRs), also known as
seven-transmembrane domain receptors,
7TM receptors,
heptahelical receptors,
serpentine receptor, and
G protein–linked receptors (
GPLR), constitute a large
protein family of
receptors, the
G-protein-coupled receptor (GPCR) Family (
TC# 9.A.14] (a superfamily/family within the
TOG Superfamily ), that sense
molecules outside the
cell and activate inside
signal transduction pathways and, ultimately, cellular responses. Coupling with
G proteins, they are called seven-transmembrane receptors because they pass through the cell membrane seven times.
