Microtubule inner protein (MIP) part of the dynein-decorated doublet microtubules (DMTs) in flagellum axoneme. May serve to reinforce and thus stabilize the microtubule structure in the sperm flagella.
Subcellular locations: Cytoplasm, Cytoskeleton, Flagellum axoneme, Cytoplasm, Nucleus
Localizes to the A-tubules of DMTs (By similarity). Located in the cytoplasm of spermatocytes and the nuclei of round spermatids and elongated spermatids (By similarity).
Expressed in testis (at protein level). Strongly expressed in peritubular cells and Leydig cells and weakly expressed in the cytoplasm of spermatocytes.