Protoplast fusion method for efficient transformation of mouse spermatogenic cells

Foreign gene expression by in vivo gene electroporation in the quail testis

To investigate whether or not foreign gene expression is attained in the testis of living Japanese quails, a firefly luciferase reporter gene was transfected by in vivo electroporation (EP), and transcriptional activity of different promoters was compared. In addition, the effect of the Epstein-Barr virus self-replication sequence was also tested. The results showed that luciferase activity in the testis reached almost a plateau value at 50 V. Under this EP condition, no difference was found in transcriptional activity between the simian virus 40 (SV40) and miw promoters. The reporter gene expression in the quail testis was observed over 28 days after in vivo gene EP, although the activity gradually decreased, and the presence of the Epstein-Barr virus self-replication sequence in the SV40 promoter did not significantly prolong the luciferase activity. These results suggest that in vivo gene EP confers strong, though transient, foreign gene expression in the Japanese quail, and it may provide a new powerful approach for studies on transcriptional regulation of genes during proliferation and differentiation of spermatogenic cells in the quail testis.

Foreign gene expression in the mouse testis by localized in vivo gene transfer

In order to attain foreign gene expression in vivo in the testis of living mice, chloramphenicol acetyltransferase (CAT), firefly luciferase and bacterial lacZ reporter genes were transfected by microparticle bombardment and electroporation. The results showed that CAT reporter gene was expressed in a dose-dependent fashion. The X-gal staining showed that in some spermatogenic-like cells, the bacterial lacZ gene was also expressed by in vivo electroporation, but not by in vivo microparticle bombardment. The possibility of in vivo gene transfer to the spermatogenic cells of the mouse testis was further confirmed by the fact that the CAT reporter gene expression was testis-specific when driven by the mouse-protamin 1 promoter. It was concluded, therefore, that in vivo microparticle bombardment and, especially, electroporation provide convenient and efficient means of gene transfer to the testis of living mice.