The protein encoded by this gene contains ten Armadillo repeat motifs (ARMs) and one HEAT repeat, and is thought to be involved in ciliary and flagellar movement. This protein has been shown to localize to the ciliary axonemes and at the ciliary base of respiratory cells. Studies indicate that mutations in this gene cause partial outer dynein arm (ODA) defects in respiratory cilia. The cilia of cells with mutations in this gene displayed either reduced ciliary beat frequency and amplitude, or, complete immotility. Some individuals with primary ciliary dyskensia (PCD) have been shown to have mutations in this gene. PCD is characterized by chronic airway disease and left/right body asymmetry defects. Alternative splicing results in multiple transcript variants encoding different isoforms. [From RefSeq]