Protamine-derived synthetic peptide enhances the efficiency of sperm-mediated gene transfer using liposome-peptide-DNA complex

摘要

Sperm-mediated gene transfer (SMGT), which uses sperm cells as vectors for DNA delivery during fertilization, is one of the methods used to achieve transgenesis in animals as an alternative to pronuclear microinjection. Despite the convenience of SMGT, its application in producing transgenic animals, especially domestic animals, is still limited due to its low success rate. In this study, to increase the efficiency of SMGT, we tested liposome-peptide-DNA (LPD) complex, a new reagent known to stabilize transfection in cultured cells. Two peptides, one designed from the amino acid sequence of human histone H1 (Hs) and the other from human protamine (Pr), were used with a CMV/beta-actin/EGFP fusion gene to form LPD complex. Spermatozoa obtained from rat epididymis were incubated with LPD complex and used for artificial insemination, and the expression of EGFP in the morula-stage embryos was observed. Pr caused significantly more embryos to express EGFP, while Hs had no effect on the expression rate. Moreover, only Pr resulted in the production of offspring carrying foreign DNA. These results suggest that LPD complex with the aid of Pr could be useful in the transfer of foreign DNA by SMGT, probably by stabilizing liposome-DNA complex during fertilization.