Find FZD1 Products Interaction Network for FZD1 FZD1 Details

Related Pathways Wnt / beta-catenin Signaling Axonal Guidance Signaling View All Pathways

Synonyms: AW227548, DKFZp564G072, Frizzled 1, FZ-1, FZD1, Rfz1

Frizzled/PCP Pathway in D. Melanogaster

The Frizzled (Fz) receptor family members are seven transmembrane domain proteins that transduce two unique pathways, the canonical/beta-catenin (Armadillo, ARM) pathway and the non-canonical/planar cell polarization (PCP) pathway. Both pathways involve the regulation and redistribution of the common downstream effector Dishevelled (Dsh).

Planar cell polarity is a process in which epithelial cells become uniformly polarized to establish an area of aligned structures such as hair orientation. The PCP mechanism requires the asymmetric localization of planar polarity proteins. This is a two stage process involving the apicolateral localization of planar polarity proteins to the adherens junction zone followed by asymmetric distribution on the proximodistal axis. This process involves the activity of the small GTPase, RhoA and Rho-kinase to remodel cytoskeletal structures, as well as a number of effector/regulators of the polarization process. A number of gene products involved in the Frizzled/CPC pathway have emerged. They include Van Gogh/strabismus, Flamingo, Prickle and Diego. Diego binds to Disheveled and promotes PCP, whereas Prickle competes with Diego for binding to Disheveled and amplifies asymmetric Frizzled and Dishevelled localization. Van Gogh together with Frizzled and Flamingo, an atypical cadherin, mediates the apicolateral recruitment of Dishevelled and Prickle.

It is still not clear how frizzled receptors differentially signal the beta-catenin and PCP pathways. One model proposes that the PCP pathway is active when the Frizzled receptors are unoccupied by Wnt (wingless) ligands. Frizzled is a serpentine receptor that until recently was believed to not be G-protein linked. However, recent studies suggest that Frizzled is linked to a G-protein containing a Galpha(o) (Gαo) subunit and that this subunit is involved in PCP and linked to cytoskeletal organization.