Expression of TRP53 in embryos at various developmental stages. Densitometric analysis of TRP53 expression as shown in inset. Optical density of p53 band/Lis-1 band *100. The numbers on X-axis represent – Cultured: embryos were collected at the zygote stage and cultured for: (1) 24 h, (2) 48 h, (3) 72 h, (4) 90 h. Fresh: were collected directly from the reproductive tract at the (1) zygote, (2) 2-cell, (3) morula, and (4) blastocyst stages. (5) A positive control for the expression of TRP53 was the analysis of ~1000 T47D breast cancer cells. Inset – Western blotting analysis of 30 embryos at various development stages. After analysis of TRP53 expression membranes were stripped and re-probed for expression of the constitutively expressed Lis-1 protein. The results are representative of 3 replicates. The numbers correspond to those on the graph.