Sperm-mediated gene transfer into oocytes of the golden hamster: assessment of sperm function.
The possibility of sperm as a vehicle to deliver foreign DNA to oocytes was tested in hamsters. Epididymal spermatozoa, incubated with linearized plasmid DNA encoding ovine growth hormone (pCMXoGH), showed a spontaneous tendency to interact with DNA. Kinetics of sperm uptake of DNA was determined by using [32P]-labeled DNA. Spermatozoa took up the added DNA by 15-30 min and the uptake was inhibited by human seminal fluid in a dose dependent manner. Addition of DNA did not affect the functional competence of spermatozoa, in terms of their ability to undergo capacitation and acrosome reaction (34.5% +/- 2.2 vs 35% +/- 1.5). The fertilizing ability of DNA treated-spermatozoa from hamsters and humans was assessed by zona-free hamster egg penetration assay. Number of sperm penetrated per oocyte were 23 +/- 4.5 and 1.4 +/- 1.3 for hamster and human spermatozoa, respectively. Penetrated oocytes harbored sperm-treated DNA both with hamster (30.2 cpm/oocyte) and human (19.2 cpm/oocyte) spermatozoa. These results show that the hamster and human spermatozoa have a strong tendency to interact with exogenous (foreign) DNA and are able to transfer DNA to oocytes. Sperm may be used as a vector for DNA transfer and this approach has potential in the production of transgenic animals.
Fernandez
M A
MA
Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, India.
Mani
S A
SA
Rangarajan
P N
PN
Seshagiri
P B
PB
D000818:Animals; D001483:Base Sequence; D006224:Cricetinae; D017931:DNA Primers / Q000235:genetics; D005260:Female; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D006801:Humans; D008297:Male; D008647:Mesocricetus; D013084:Sperm-Ovum Interactions / Q000235:genetics*; D013094:Spermatozoa / Q000502:physiology
D017931:DNA Primers