Abstract: | The cell cycle structure in the cells of loach embryos at the early blastula stage (5 h of development at 21 degrees) is markedly altered under the influence of injection of homologous low molecular weight nuclear RNA and, as a result, the number of cells in G2-phase. The DNA amount in the embryo increases by 20%. At the midblastula stage (7 h) no increase in the number of cells in G2-phase was found. |