Figure 3
From: Functional aspects of primary cilia in signaling, cell cycle and tumorigenesis
Canonical and non-canonical/PCP-signaling and cilia. (A) Canonical Wnt-signaling. When cilia are present, multiple mechanisms dampen Wnt-signaling; DVL is recruited by INVS/NPHP2 to the cilium, normal flow sensation elevates intracellular Ca2+ levels that switch Wnt-signaling off, Jouberin (Jbn) sequesters a pool of β-catenin and recruits it to the ciliary compartment. In cilia mutants, mislocalized INVS fails to recruit DVL, which translocates to the membrane and activates Wnt-signaling. Ca2+ response is lost, which fails to switch Wnt-signaling off. Jbn and β-catenin potentiate Wnt-signaling as a larger pool can translocate to the nucleus. (B) Illustrative model of cystic expansion of a renal tubule in a polycystic kidney. Disturbed PCP affects the orientation of cell division within the plane of tissue organization.