Source:http://www.reactome.org/biopax/48887BiochemicalReaction3494
| Predicate | Object |
|---|---|
| rdf:type | |
| biopax3:comment |
Authored: Gopinathrao, G, 2005-05-18 22:14:39,
Edited: Jupe, S, 2009-09-09,
Reviewed: Jupe, S, 2009-03-10 09:59:17,
When a ligand activates a G protein-coupled receptor, it induces a conformational change in the receptor (a change in shape) that allows the receptor to function as a guanine nucleotide exchange factor (GEF), stimulating the exchange of GDP for GTP on the G alpha subunit. In the traditional view of heterotrimeric protein activation, this exchange triggers the dissociation of the now active G alpha subunit from the beta:gamma dimer, initiating downstream signalling events. The G alpha subunit has intrinsic GTPase activity and will eventually hydrolyze the attached GTP to GDP, allowing reassociation with G beta:gamma. Additional GTPase-activating proteins (GAPs) stimulate the GTPase activity of G alpha, leading to more rapid termination of the transduced signal. In some cases the downstream effector may have GAP activity, helping to deactivate the pathway. This is the case for phospholipase C beta, which possesses GAP activity within its C-terminal region.
|
| biopax3:xref | |
| biopax3:dataSource | |
| biopax3:displayName |
G alpha (s) auto-inactivates by hydrolysing GTP to GDP
|
| biopax3:eCNumber |
3.6.5.1,
3.6.5.2,
3.6.5.3,
3.6.5.4
|
| biopax3:left | |
| biopax3:right |