Fig. 2. sno is required for blastocyst formation. Embryos were recovered from (sno^+/– × sno^+/–) intercrosses at E1.5 (two-cell stage) and cultured for different lengths of time, as indicated. Photographs in the right-hand column show an abnormal embryo, which decompacts and fails to form a blastocyst, whereas those in the left-hand column show a normal embryo. Embryos at the eight-cell stage are also shown stained with Sno-specific monoclonal antibodies (bottom panels).