Synembryn B (SYNB)

The deduced 520-amino acid rat protein shares 86% identity with the deduced 536-amino acid human protein over the first 483 amino acids; their C termini are completely divergent. RIC8B shares 40% amino acid identity with mouse synembryn (RIC8A).

Carbachol, a cholinergic agonist, induced the reversible translocation of fluorescence-tagged RIC8B from the cytosol to the plasma membrane of human neuroblastoma cells. In rat pheochromocytoma cells and human neuroblastoma cells, treatment with carbachol led to the colocalization of RIC8B with plasma membrane GNAQ, and treatment with isoproterenol, a beta-adrenergic agonist, led to the colocalization of RIC8B with plasma membrane GNAS.