Seems to play a role in sperm motility. Interacts with CALM1. In mature sperm, localizes in the midpiece of flagella. Expressed in testis (at protein level). Expression increases from 3 weeks to 6 months (PubMed:29025071). In mouse testis, mainly localized in the cytoplasm of round spermatids and elongated spermatids. In the cap phase, remains close to the acrosomes but begins to migrate to other regions around the nuclei. As spermiogenesis progresses, further separates from the acrosomes. In the acrosome phase, while the acrosomes formed hook-like structures and move toward one end of the nuclei, GARIN2 moveS to the opposite end. In the maturation phase, moves to the end opposite to the acrosomes and, at the end of spermiogenesis, is removed to the residue body together with most of the other cytosolic components. Finally, in caudal sperm, is retained in sperm flagella. In mature sperm, GARIN2 localizes in the midpiece of flagella (PubMed:29025071). Belongs to the GARIN family.