Required for normal spermatogenesis (PubMed:30032984, PubMed:30298696). It functions as a scaffold protein that attaches the sperm head-tail connecting piece to the nuclear envelope, thus maintaining sperm head and tail integrity (PubMed:30032984). May also be involved in the general organization of cellular cytoskeleton. Localized at the sperm head-tail connecting piece (PubMed:30032984, PubMed:30298696). During spermatogenesis, it is first observed in the cytoplasm of round spermatids, it later appears in the implantation fossa region of the sperm nucleus during sperm head elongation and differentiation, and finally it localizes to the head-tail connecting piece (PubMed:30032984). Expressed in the testis. Knockout male mice are infertile and have acephalic spermatozoa, while females are fertile and show normal follicle development.