Synembryn (SYN)

Ric8a, a homolog of C. elegans Ric8/synembryn. Database analysis identified 3 splice variants of human RIC8A that encode deduced proteins of 531, 537, and 401 amino acids. The 531-amino acid RIC8A isoform shares 87% identity with rat Ric8a. The 537-amino acid protein is identical to the 531-amino acid protein except for a 6-amino acid insertion, including a polyproline sequence, at codon 355.

The variant encoding the 401-amino acid protein is derived from a 1-bp insertion at codon 395 of the transcript encoding the 531-amino acid protein. The resultant frameshift leads to a protein with 5 different C-terminal amino acids and a new stop codon that forms a consensus CAAX box for geranylgeranyl modification.