Heterogeneous distribution of histone methylation in mature human sperm.
OBJECTIVE
To analyze the presence of various histone modifications in ejaculated human spermatozoa


METHODS
In this prospective study, seminal ejaculates from 39 normozoospermic individuals were evaluated for semen analysis and the presence of histone modifications in isolated nuclei.


RESULTS
We observed heterogeneous presence of histone methylation in normal mature human sperm. We observed that 12 to 30 % of the nuclei of normal sperm contain a heterogeneous distribution of the marks H3K4Me1, H3K9Me2, H3K4Me3, H3K79Me2, and H3K36Me3. Moreover, the presence of these marks is higher in the poor motile fraction of the ejaculate, which is associated with poor morphology and functional quality. In contrast, we did not observe histone acetylation (H3K4Ac and H4K5Ac) in normal or abnormal mature human sperm


CONCLUSIONS
Defects in the process of spermatogenesis may alter the correct epigenetic programming in mature sperm. Further studies are required to evaluate the impact of these findings in human infertility.
Instituto de Biología y Medicina Experimental, CONICET, Vuelta de Obligado 2490, 1428, Buenos Aires, Argentina.
Florenza A
FA
La Spina
Marina
M
Romanato
Santiago
S
Brugo-Olmedo
Sabrina
S
De Vincentiis
Vanina
V
Julianelli
Rocio M
RM
Rivera
Mariano G
MG
Buffone
D002467:Cell Nucleus / Q000378:metabolism; D044127:Epigenesis, Genetic; D006367:HeLa Cells; D000076983:Histone Methyltransferases; D011495:Histone-Lysine N-Methyltransferase / Q000378:metabolism*; D006657:Histones / Q000378:metabolism*; D006801:Humans; D008297:Male; D008745:Methylation; D055101:Semen Analysis; D013091:Spermatogenesis / Q000235:genetics; D013094:Spermatozoa / Q000378:metabolism*
D006657:Histones; D000076983:Histone Methyltransferases; D011495:Histone-Lysine N-Methyltransferase