The Retinoic Acid-Inducible orphan G-protein-coupled receptors (RAIG) are a group of four closely related G protein-coupled receptor

G protein-coupled receptor

G protein-coupled receptors , also known as seven-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptor, and G protein-linked receptors , comprise a large protein family of transmembrane receptors that sense molecules outside the cell and activate inside signal...

s whose expression is induced by retinoic acid

Retinoic acid

Retinoic acid is a metabolite of vitamin A that mediates the functions of vitamin A required for growth and development. Retinoic acid is required in chordate animals which includes all higher animals from fishes to humans...

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The exact function of these proteins has not been determined but they may provide a mechanism by which retinoic acid can influence G protein signal transduction cascades. In addition, RAIG receptors interact with members of the frizzled

Frizzled

Frizzled is a family of G protein-coupled receptor proteins that serve as receptors in the Wnt signaling pathway and other signaling pathways. When activated, Frizzled leads to activation of Dishevelled in the cytosol.-Species distribution:...

 class of G protein-coupled receptors and appear to activate the Wnt signaling pathway

Wnt signaling pathway

The Wnt signaling pathway is a network of proteins best known for their roles in embryogenesis and cancer, but also involved in normal physiological processes in adult animals.-Discovery:...

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