Regulator of G-protein signaling 2 is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respon ...
that in humans is encoded by the ''RGS2''
gene
In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...
.
It is part of a larger family of
RGS protein
Regulators of G protein signaling (RGS) are protein structural domains or the proteins that contain these domains, that function to activate the GTPase activity of heterotrimeric G-protein α-subunits.
RGS proteins are multi-functional, GTPase-a ...
s that control signalling through
G-protein coupled receptor
G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptors, and G protein-linked receptors (GPLR), form a large group of evolutionarily-related p ...
s (GPCR).
Function
RGS2 is thought to have protective effects against
myocardial hypertrophy as well as
atrial arrhythmias.
Increased stimulation of
Gs coupled
β1-adrenergic receptors and
Gq coupled α1-adrenergic receptors in the heart can result in cardiac hypertrophy.
In the case of Gq protein coupled receptor (GqPCR) mediated hypertrophy,
Gαq will activate the intracellular affectors
phospholipase C
Phospholipase C (PLC) is a class of membrane-associated enzymes that cleave phospholipids just before the phosphate group (see figure). It is most commonly taken to be synonymous with the human forms of this enzyme, which play an important role i ...
β and
rho guanine nucleotide exchange factor to stimulate cell processes which lead to cardiomyocyte hypertrophy.
RGS2 functions as a GTPase Activating Protein (GAP) which acts to increase the natural GTPase activity of the Gα subunit.
By increasing the GTPase activity of the Gα subunit, RGS2 promotes GTP hydrolysis back to GDP, thus converting the Gα subunit back to its inactive state and reducing its signalling ability.
Both GsPCR and GqPCR activation can contribute to cardiac hypertrophy via act