Enables nuclear import signal receptor activity. Involved in NLS-bearing protein import into nucleus; cellular response to amino acid stimulus; and positive regulation of protein import into nucleus. Located in cytoplasm and nucleus. Is expressed in germ cell of testis; gonad; ovary; spermatid; and testis. Orthologous to human IPO5 (importin 5). [provided by Alliance of Genome Resources, Apr 2022]