synembryn-A (protein Ric-8A, RIC8A)

Function: - guanine nucleotide exchange factor - can activate some, but not all, G-alpha proteins - able to activate GNAI1, GNAO1 & GNAQ, but not GNAS by exchanging bound GDP for free GTP - role in regulation of microtubule pulling forces during mitotic movement of chromosomes by stimulating Gi-alpha protein, possibly leading to release Gi-alpha-GTP & NuMA proteins from the NuMA-GPSM2-Gi-alpha-GDP complex - activator for Gq-alpha (GNAQ)protein by enhancing the Gq-coupled receptor-mediated ERK activation - interacts with GDP-bound G alpha proteins GNAI1, GNAO1 & GNAQ, & with GNA13 with lower affinity - does not interact with G-alpha proteins when they are in complex with subunits beta & gamma (putative) - phosphorylated upon DNA damage, probably by ATM or ATR Structure: belongs to the synembryn family Compartment: cytoplasm (putative) Alternative splicing: named isoforms=3

General

guanine nucleotide exchange factor (GDP/GTP dissociation stimulator, guanine nucleotide-releasing factor/protein, GNEF, GNDS, GDS) phosphoprotein

Properties

SIZE: MW = 60 kD entity length = 530 aa COMPARTMENT: cytoplasm MOTIF: Ser phosphorylation site {S30} Ser phosphorylation site {S435}

References

UniProt :accession Q9NPQ8