Highlights

There has been a breakthrough in the number of reported Frizzled family (SMO and FZDs) GPCR structures, including transmembrane domain structures, extracellular domain structures, and multidomain structures.

New insight has been obtained in the ligand-binding sites, including orthosteric GPCR ligand-binding pockets in the transmembrane domains, and the unique lipid-binding groove and other ligand-binding sites in the extracellular domains.

Oligomerization remains a controversial issue in regards to dimerization and signalosome assembly.

Class Frizzled receptors are important for oncology drug discovery.