Chimerization of highly asynchronous murine blastomeres: developmental alteration?

Previous studies have shown that early embryos contain information that can alter the developmental fate of adjacent cells and transferred nuclei. In this report we show that a specific combination of cells from early murine embryos, a single blastomere from an eight-cell embryo placed under the zona pellucida with a two-cell embryo, results in a difference in incorporation of 3H-uridine and expression of two protein bands between the chimeric treatment group and the nonchimeric controls, a single blastomere from an eight-cell embryo in a separate zona pellucida and a two-cell embryo. The incorporation of 3H-uridine in the chimeric group and nonchimeric control group was significantly different at 45 hours after chimerization (P less than .02). A stage-specific protein band (52k) on a polyacrylamide gel detected with fluorography was found to be qualitatively different (present more often; P less than .01) and another stage-specific protein band (48k) was found to be quantitatively different (more protein; P = .07) in the chimeric treatment vs. the nonchimeric controls at 45 hours after chimerization. These results suggest communication between the cells resulting in a change in their incorporation of uridine and protein synthetic profiles.