Influence of sex chromosome constitution on the genomic imprinting of germ cells.
Germ cells in XY male mice establish site-specific methylation on imprinted genes during spermatogenesis, whereas germ cells in XX females establish their imprints in growing oocytes. We showed previously that in vitro, sex-specific methylation patterns of pluripotent stem cell lines derived from germ cells were influenced more by the sex chromosome constitution of the cells themselves than by the gender of the embryo from which they had been derived. To see whether the same situation would prevail in vivo, we have now determined the methylation status of H19 expressed from the maternal allele, and the expression and methylation status of a paternally expressed gene Peg3, in germ cells from sex-reversed and control embryos. For these imprinted genes, we conclude that the female imprint is a response of the germ cells to undergoing oogenesis, rather than to their XX chromosome constitution. Similarly, both our XY and our sex-reversed XX male germ cells clearly showed a male rather than a female pattern of DNA methylation; here, however, the sex chromosome constitution had a significant effect, with XX male germ cells less methylated than the XY controls.
Durcova-Hills
Gabriela
G
Wellcome Trust/Cancer Research UK Gurdon Institute of Cancer and Developmental Biology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, United Kingdom.
Hajkova
Petra
P
Sullivan
Stephen
S
Barton
Sheila
S
Surani
M Azim
MA
McLaren
Anne
A
D000818:Animals; D001483:Base Sequence; D019175:DNA Methylation; D005260:Female; D018392:Genomic Imprinting; D005854:Germ Cells / Q000166:cytology*; D008297:Male; D051379:Mice; D008957:Models, Genetic; D008969:Molecular Sequence Data; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated / Q000235:genetics; D012730:Sex Chromosomes / Q000235:genetics*; D013447:Sulfites / Q000494:pharmacology; D019076:Transgenes
C094335:H19 long non-coding RNA; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; D013447:Sulfites