This gene product belongs to the tektin family of proteins. Tektins comprise a family of filament-forming proteins that are coassembled with tubulins to form ciliary and flagellar microtubules. The exact function of this gene is not known. Structural component of ciliary and flagellar microtubules. Forms filamentous polymers in the walls of ciliary and flagellar microtubules. Required for progressive sperm mobility.