Microtubule inner protein (MIP) part of the dynein-decorated doublet microtubules (DMTs) in cilia and flagellar axoneme . Forms filamentous polymers in the walls of ciliary and flagellar microtubules (By similarity). Contributes to normal sperm motility (By similarity).
Subcellular locations: Cytoplasm, Cytoskeleton, Cilium axoneme, Cell projection, Cilium, Flagellum
Found in the abaxial (convex) surface of outer dense fibers in sperm flagella.
Strongly expressed in spermatozoa. Also detected at low levels in pancreas. Expressed in airway epithelial cells .