The protein encoded by this gene is similar to a sea urchin radial spoke head protein. Radial spoke protein complexes form part of the axoneme of eukaryotic flagella and are located between the axoneme's outer ring of doublet microtubules and central pair of microtubules. In Chlamydomonas, radial spoke proteins are thought to regulate the activity of dynein and the symmetry of flagellar bending patterns. This gene maps to a region of chromosome 19 that is linked to primary ciliary dyskinesia-2 (CILD2). [provided by RefSeq, Jul 2008].