Characterization of blastocyst ISP expression. A and B- Western blot analysis showing the expression of the ISP1- ISP2 enzyme complex from 3.5 dpc blastocysts when probed with anti-ISP1 (A) and anti-ISP2 (B) mAbs. C- RT-PCR from pre-implantation embryos. Lanes 1–4 and 6–10 represent samples amplified using ISP1 and ISP2 primers, respectively: lanes 4 and 6: non-pregnant uterus cDNA (negative control); lanes 3 and 7: 2.5 dpc embryo cDNA; lanes 2 and 8: 3.5 dpc embryo cDNA; lanes 1 and 9 represent 4.5 dpc embryo cDNA. Lane 5 is the 1 kb plus DNA ladder.