Differential expression of regulator of G-protein signaling R12 subfamily members during mouse development.

Regulators of G-protein Signaling (RGS proteins) are a multigene family of GTPase-accelerating proteins for the Galpha subunit of heterotrimeric G-proteins. The mammalian R12 RGS protein subfamily is composed of RGS12 and RGS14, two proteins characterized by their multidomain architecture of hallmark RGS domain, tandem Ras-binding domains (RBDs), and a second Galpha interacting domain, the GoLoco motif. The Rgs12 gene generates multiple splice variants, the largest of which encodes N-terminal PDZ and PTB domains in addition to the core RGS/RBD/GoLoco motifs. The Rgs14 gene encodes a protein similar to the non-PDZ/PTB domain RGS12 splice variants. The spatiotemporal expression patterns of RGS12 and RGS14 proteins were examined by immunohistochemistry in a developmental series of postimplantation mouse embryo. We report that RGS12 splice variants exhibit differential spatiotemporal patterns of expression during postimplantation embryogenesis, suggesting nonoverlapping roles. In contrast, RGS14 is found ubiquitously throughout the postimplantation period. We conclude that R12 subfamily RGS proteins likely play significant and different roles in specific tissues and periods of mouse embryogenesis.