Cilia Disease

Cilia are small tail-like projections on the cell surface. There are two types: motile cilia and nonmotile, or primary, cilia, which can serve as sensory organelles. Recently, primary cilia have been implicated in a variety of human diseases collectively known as genetic “ciliopathies.” Hedgehog (Hh) signaling is associated with basal cell carcinoma (BCC) and is normally restrained by the PTCH1 tumor suppressor (see JW Dermatol Sep 2 2009). Recent evidence suggests that the primary cilia play a role in modulating mammalian Hh signaling and that Ptch1 suppresses the Hh pathway, in part, by blocking the trafficking of Smoothened (Smo) into the primary cilium. In fact, an activated mutant form of Smo localizes constitutively to the cilium.

Alth…