Reverse transcriptase activity in mature spermatozoa of mouse.
We show here that a reverse transcriptase (RT) activity is present in murine epididymal spermatozoa. Sperm cells incubated with human poliovirus RNA can take up exogenous RNA molecules and internalize them in nuclei. Direct PCR amplification of DNA extracted from RNA-incubated spermatozoa indicate that poliovirus RNA is reverse-transcribed in cDNA fragments. PCR analysis of two-cell embryos shows that poliovirus RNA-challenged spermatozoa transfer retrotranscribed cDNA molecules into eggs during in vitro fertilization. Finally, RT molecules can be visualized on sperm nuclear scaffolds by immunogold electron microscopy. These results, therefore, reveal a novel metabolic function in spermatozoa, which may play a role during early embryonic development.
Giordano
R
R
CNR Center for the Study of Germinal Cells, University of Siena, 53100 Italy.
Magnano
A R
AR
Zaccagnini
G
G
Pittoggi
C
C
Moscufo
N
N
Lorenzini
R
R
Spadafora
C
C
D000818:Animals; D002467:Cell Nucleus / Q000201:enzymology* / Q000648:ultrastructure; D004822:Epididymis; D005260:Female; D006801:Humans; D007700:Kinetics; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D009865:Oocytes / Q000502:physiology; D017955:Poliovirus / Q000235:genetics; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000378:metabolism*; D012194:RNA-Directed DNA Polymerase / Q000378:metabolism*; D013081:Sperm Motility; D013094:Spermatozoa / Q000201:enzymology* / Q000502:physiology / Q000648:ultrastructure
D012367:RNA, Viral; D012194:RNA-Directed DNA Polymerase