While the expression and epigenetic differences of imprinted genes have been extensively characterized in the @entity19 and @entity1 , little is known about imprinted genes in livestock species. In the current study, eight genes that are imprinted in the @entity1 or @entity19 were investigated in preimplantation @entity291 embryos. Amplified cDNA was created from three single metaphase II (MII) oocytes or embryos throughout preimplantation development. The imprinted genes @entity70509 and @entity70510 (isoform 1) had no detectable transcripts during preimplantation development. @entity70511 and @entity70512 were expressed in most embryos from the 2-cell to blastocyst stages of development. @entity70510 (isoform 2) was expressed in all oocytes and embryos, except for one blastocyst sample. @entity70513 and Xist were expressed from the 8-16-cell stage (maternal-to-zygotic transition, MZT) onwards. @entity70514 was expressed until the MZT, and @entity70515 in both early (alpha form) and late (beta form) stage embryos. The paternally imprinted genes @entity70511 , @entity70512 , and Xist were expressed in both @entity52 ( @entity52 ) and parthenogenetically activated (PA) blastocysts as expected. Of the four maternally imprinted genes expressed in the blastocyst ( @entity70510 , @entity70513 , @entity70515 , and @entity70514 ), @entity70515 alone showed differential mRNA expression between @entity52 and PA blastocysts, suggesting imprinting by this stage of development. In conclusion, seven of the eight genes investigated showed mRNA expression during preimplantation development, indicating a potential role during early development. Also significant is the observation that @entity70515 is imprinted by the blastocyst stage of development although the other genes are not, indicating a temporal imprinting program.

Analysis of imprinted messenger RNA expression during XXXX preimplantation development.

@entity1 :: ('9606', 'Species') :: ['human'] @entity52 :: ('MESH:C566179', 'Disease') :: ['IVF', 'in vitro-fertilized'] @entity19 :: ('10090', 'Species') :: ['mouse'] @entity70512 :: ('407210(Tax:9913)', 'Gene') :: ['Grb10'] @entity70509 :: ('281117(Tax:9913)', 'Gene') :: ['Dlk1'] @entity70513 :: ('386664(Tax:9913)', 'Gene') :: ['Ndn'] @entity70515 :: ('353114(Tax:9913)', 'Gene') :: ['Nnat'] @entity70514 :: ('407209(Tax:9913)', 'Gene') :: ['Sgce'] @entity291 :: ('9913', 'Species') :: ['bovine'] @entity70511 :: ('281793(Tax:9913)', 'Gene') :: ['Gnas'] @entity70510 :: ('404180(Tax:9913)', 'Gene') :: ['Mest']
@entity291 :: (9913,Species) :: ['bovine']
