Background：IQCB1, also known as NPHP5, is a nephrocystin protein that interacts with calmodulin and the retinitis pigmentosa GTPase regulator protein. It has a central coiled-coil region and two calmodulin-binding IQ domains. Localized to the primary cilia of renal epithelial cells and connecting cilia of photoreceptor cells, IQCB1 is thought to play a role in ciliary function. Mutations in this gene result in Senior-Loken syndrome type 5, a juvenile disorder characterized by defects in the waste filtering system of the kidney, as well as retinal degradation.
