MGI:1095411Embryos homozygous for a null mutation die between 4.0 and 4.5 dpc, following depletion of maternally-derived gene product. In vitro, cultured 3.5-dpc mutant embryos arrest in the G2 phase, and show blastocoel contraction with defects in NLS-mediated protein import and polyadenylated RNA export.