Federal University of Espírito Santo, Alegre, ES, 29500-000, Brazil.
University of Brasilia, Animal Science, Merk Millipore /Sigma-Aldrich Brasil, São Paulo, DF, 70910-900, Brazil.
In Vitro Cell Dev Biol Anim. 2021 Jun;57(6):598-609. doi: 10.1007/s11626-021-00599-x. Epub 2021 Jun 14.
It is well-established that in vitro culture affects quality, gene expression, and epigenetic processes in bovine embryos and that trophectoderm cells are the most susceptible to abnormalities. These changes have been reported as the main factors responsible for losses observed after transfer of in vitro-produced embryos. The present study aimed to investigate the effect of an in vitro system on bovine embryo transcriptional profiles on D14 of development. Two groups were used-one with embryos produced in vitro until D7 (day 7; VT group) and another with embryos produced in vivo by hormonal stimulation, with embryos collected on D7 (VV group). D7 embryos at similar developmental stages from both treatments were transferred to recipient uteri and recollected on D14. From D14 embryos of both treatments, trophoblast samples were removed by biopsy for sexing and transcriptome analyses. Embryos were sexed by polymerase chain reaction (PCR), and only males were used for RNA sequencing. In total, 29,005 transcripts were expressed, from which 900 were differentially expressed, but only 29 genes were significantly differentially expressed. In addition, 20 genes were found uniquely for VV and 27 for VT. These findings suggested that although the uterine environment minimized transcriptional differences, it was not able to make trophoblasts from the in vitro embryos similar to the in vivo ones. The few genes exhibiting differences are in control of important events that may be responsible for embryonic losses occurring during the first period of gestation.
已经证实,体外培养会影响牛胚胎的质量、基因表达和表观遗传过程,滋养外胚层细胞对异常情况最敏感。这些变化被认为是导致体外生产胚胎移植后观察到的损失的主要因素。本研究旨在研究体外系统对牛胚胎在发育第 14 天转录谱的影响。使用了两组,一组是在体外培养至第 7 天(VT 组)的胚胎,另一组是通过激素刺激在体内产生的胚胎,第 7 天收集(VV 组)。来自两种处理的具有相似发育阶段的第 7 天胚胎被转移到受体子宫中,并在第 14 天重新收集。从两种处理的第 14 天胚胎中,通过活检去除滋养外胚层样本进行性别鉴定和转录组分析。胚胎通过聚合酶链反应(PCR)进行性别鉴定,仅雄性用于 RNA 测序。总共表达了 29005 个转录本,其中 900 个差异表达,但只有 29 个基因显著差异表达。此外,VV 有 20 个基因和 VT 有 27 个基因是独特的。这些发现表明,尽管子宫环境最大限度地减少了转录差异,但它仍无法使体外胚胎的滋养外胚层与体内胚胎相似。少数表现出差异的基因控制着重要的事件,这些事件可能是导致妊娠早期胚胎丢失的原因。