This gene encodes a protein that appears to be a component the radial spoke head, as determined by homology to similar proteins in the biflagellate alga Chlamydomonas reinhardtii and other ciliates. Radial spokes, which are regularly spaced along cilia, sperm, and flagella axonemes, consist of a thin 'stalk' and a bulbous 'head' that form a signal transduction scaffold between the central pair of microtubules and dynein. [From RefSeq]