Regulator of G-Protein Signaling

Regulator of G-protein signaling 5 (RGS5) binds directly to activated G alpha subunits and act as GTPase-activating proteins (GAPs) in order to weaken and/or modulate hormone and neurotransmitter receptor-initiated signaling by both G alpha-GTP and G beta gamma. Vascular endothelial cells express the RGS protein RGS5, where it correlates with capillary morphogenesis, consequently rendering it a candidate gene involved in capillary growth, angiogenesis, and also possibly the pathophysiology of stroke.

Regulator of G protein signaling 4 (RGS4) is a protein which regulates G protein signaling. Regulator of G protein signaling (RGS) family members are regulatory molecules which act as GTPase activating proteins (GAPs) for G alpha subunits of heterotrimeric G proteins. Heterotrimeric G proteins serve to convey information from cell surface receptors to intracellular effectors.

Regulator of G-protein signaling 21 (RGS21) belongs to the RGS family and regulatory molecules which act as GTPase activating proteins for G alpha subunits of heterotrimeric G proteins. The RGS21 protein inhibits signal transduction by increasing the GTPase activity of G protein alpha subunits thus driving them into their inactive GDP-bound form.

RGS2 belongs to the RGS family which are regulatory molecules that act as GTPase activating proteins for G alpha subunits of heterotrimeric G proteins. RGS2 inhibits signal transduction by increasing the GTPase activity of G protein alpha subunits and as a result driving them into their inactive GDP-bound form.

RGS19 is a member of RGS (regulator of G protein signaling) family and negatively regulates G protein coupled receptor signaling. RGS19 protein specifically cooperates with heterotrimeric GTP-binding protein G alpha i3 (GAI3).

RGS17 weakens the signaling activity of G-proteins by binding to activated GTP-bound G alpha subunits and performing as a GTPase activating protein (GAP), increasing the rate of conversion of the GTP to GDP. This hydrolysis allows the G alpha subunits to bind G beta/gamma subunit heterodimers, creating inactive G-protein heterotrimers, which terminates the signal. RGS17 has a vital part in ending the signaling by mu opioid receptors and development of tolerance to opioid analgesic drugs.

RGS16 is part of the ''regulator of G protein signaling'' family. RGS16 inhibits signal transduction by increasing the GTPase activity of G protein alpha subunits thereby driving them into their inactive GDP-bound form. RGS16 Binds to G(i)-alpha and G(o)-alpha, but not to G(s)-alpha. RGS16 regulates the kinetics of signaling in the phototransduction cascade.

Regulator of G-protein signaling 14 (RGS14) is a member of the regulator of G protein signaling family. RGS14 contains one RGS domain, 2 Raf-like Ras-binding domains (RBDs) and one GoLoco motif. RGS14 reduces the signaling activity of G-proteins by binding, via its GoLoco domain, to specific types of activated, GTP-bound G alpha subunits. RGS14 is a scaffolding protein which integrates G protein and H-Ras/ERK/MAP kinase signaling pathways, thus making it suitably positioned to repress plasticity in CA2 neurons. Since RGS14 is highly enriched in CA2 pyramidal neurons, it has a role in inhibition of both synaptic plasticity at these synapses and hippocampal-based learning and memory.

RGS10 is a member of the RGS family that regulate molecules which perform as GTPase activating proteins (GAPs) for G alpha subunits of heterotrimeric G proteins. RGS proteins can disengage G protein subunits of the Gi alpha, Go alpha and Gq alpha subtypes. They drive G proteins into their inactive GDP-bound forms. All RGS proteins share a conserved 120-amino acid sequence termed the RGS domain. The nucleus localized RGS10 is associates specifically with the activated forms of the two related G-protein subunits, G-alphai3 and G-alphaz but is unable to cooperate with the structurally and functionally distinct G-alpha subunits.

RGS1 belongs to the regulator of G-protein signaling family. The RGS1 protein is situated on the cytosolic side of the plasma membrane and contains a conserved, 120 amino acid motif termed the RGS domain. RGS1 diminish s the signaling activity of G-proteins by binding to activated, GTP-bound G alpha subunits and performing as a GTPase activating protein (GAP), boosting the rate of conversion of the GTP to GDP. This hydrolysis allows the G alpha subunits to bind G beta/gamma subunit heterodimers, creating inactive G-protein heterotrimers, thus terminating the signal.