ABSTRACT
We studied the influence of combined microinjection of a gene engineering construct and site-specific endonuclease Sal in the pronucleus on preimplantation development of (CBA x C57BL)F1 mouse embryos in vitro. The rate of survival of the embryos was estimated according to their capacity to develop until the blastocyst stage and hatch from zona pellucida. The results obtained suggest that the microinjection of exogenous DNA jointly with endonuclease SalI at concentrations from 0.1 to 0.01 U/microl decreased reliably the rate of survival, as compared to the control (p < 0.05 and p < 0.01, respectively). However, a decrease of endonuclease SalI concentration in the injection mixture to 0.01 U/microl enhanced the capacity of mouse embryos to develop until the blastocyst stage and hatch from zona pellucida, as compared to the embryos microinjected with exogenous DNA and endonuclease SalI at a higher concentration.