Abstract
Main purpose and research question
To determine whether the true fusogen Syncytin-1 and its receptor (ASCT-2) is present in human gametes using qRT-PCR, immunoblotting and immunofluorescence.
Methods
Donated oocytes and spermatozoa, originating from a fertility center in tertiary referral university hospital, underwent qRT-PCR, immunoblotting and immunofluorescence analyzes.
Results
Quantitative RT-PCR of sperm samples from sperm donors showed that syncytin-1 is present in all samples, however, protein levels varied between donors. Syncytin-1 immunoreactivity predominates in the sperm head and around the equatorial segment. The receptor ASCT-2 is expressed in the acrosomal region and in the sperm tail. Moreover, ASCT-2, but not syncytin-1, is expressed in oocytes and the mRNA level increases with increasing maturity of the oocytes.
Conclusions
Syncytin and its receptor are present in human gametes and localization and temporal appearance is consistent with a possible role in fusion between oocyte and sperm.
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Ethical statement
All participating persons gave their informed consent prior inclusion in the study. The Danish Ethical committee approval was obtained before the study was initiated (J. nr H-B-2008-150).
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The authors declare that they have no conflict of interest.
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Capsule Membrane fusion is an important part of fertilization. Here we present, for the first time, the presence of a true fusogen Syncytin-1 and its receptor on human gametes.
This work was conducted at The Fertility Clinic, Rigshospitalet and at the Faculty of Life Science, University of Copenhagen
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Bjerregaard, B., Lemmen, J.G., Petersen, M.R. et al. Syncytin-1 and its receptor is present in human gametes. J Assist Reprod Genet 31, 533–539 (2014). https://doi.org/10.1007/s10815-014-0224-1
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DOI: https://doi.org/10.1007/s10815-014-0224-1