Required for meiosis I progression during spermatogenesis. Expressed in germ cells of the testis. Expressed from spermatogonia to spermatids. Expressed at very low levels in lung, stomach, thymus. Not detected in Sertoli cells. Germ cell-specific, but may also be expressed in cells that require the presence of germ cells. Cranial to caudal punctate expression is seen in the developing ovary starting at 13.5 dpc. At 13.5 dpc. expressed in the cranial part of the XX gonad. At 14.5 dpc, expression extends to almost two-thirds of the XX gonad, and by 15.5 dpc expression is seen throughout the entire organ. By 16.5 dpc, expression is only detected in the most caudal tip of the XX gonad. Expression switches from the embryonic ovary to the postnatal testis. Males show reduced testicular size and a tubular defects, which led to severe oligozoospermia and infertility. Spermatocytes are eliminated via apoptosis either at the pachytene checkpoint, or later at the spindle checkpoint during metaphase I. Seems to synergize with Cbfb and Myh11 during the onset of acute myeloid leukemia.