Genetic transformation of mouse embryos by microinjection of purified DNA.

TLDR

The study aims to enable gene regulation and cell differentiation research in mammals via recombinant DNA technology. A recombinant plasmid containing HSV and SV40 sequences in pBR322 was microinjected into pronuclei of fertilized mouse oocytes, embryos were implanted into pseudopregnant females, and Southern blotting was used to detect donor DNA. Two of 78 mice showed donor DNA homology, indicating successful integration of genes into the mouse genome.

Abstract

A recombinant plasmid composed of segments of herpes simplex virus and simian virus 40 viral DNA inserted into the bacterial plasmid pBR322 was microinjected into pronuclei of fertilized mouse oocytes. The embryos were implanted in the oviducts of pseudopregnant females and allowed to develop to term. DNA from newborn mice was evaluated by the Southern blotting technique for the presence of DNA homologous to the injected plasmid. Two of 78 mice in one series of injections showed clear homology, though the injected sequences had been rearranged. Band intensities from the two positive mice were consistent with the presence of donor DNA in most or all of the cells of the newborns. These results demonstrate that genes can be introduced into the mouse genome by direct insertion into the nuclei of early embryos. This technique affords the opportunity to study problems of gene regulation and cell differentiation in a mammalian system by application of recombinant DNA technology.