G Protein Signaling Modulator 2 (GPSM2)

Heterotrimeric G proteins transduce extracellular signals received by cell surface receptors into integrated cellular responses. GPSM2 belongs to a group of proteins that modulate activation of G proteins.

The deduced 677-amino acid protein has a calculated molecular mass of 76 kD. The N-terminal half of LGN contains the leu-gly-asn repeats, which are located within 7 repeats of about 40 amino acids that form alpha helices interrupted by turns. The C-terminal half of LGN contains four 34-amino acid repeats. LGN also has several potential protein kinase phosphorylation sites. human LGN shares 59% amino acid identity with rat activator of G protein signaling-3 (AGS3, or GPSM1), with most similarity in the 7 N-terminal tetratricopeptide repeats and the 4 C-terminal G protein regulatory motifs.