Animal and Crops Sciences, School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland.
Departamento de Reproducción Animal, INIA, Madrid, Spain.
Biol Reprod. 2021 Aug 3;105(2):345-358. doi: 10.1093/biolre/ioab079.
We hypothesized that sexually dimorphic differences exist in the expression of miRNAs in amniotic fluid (AF) and maternal blood plasma (MP) in association with the process of sex determination and gonad differentiation in cattle. Amniotic fluid and MP were collected from six pregnant heifers (three carrying a single male and three a single female embryo) following slaughter on Day 39 postinsemination, coinciding with the peak of SRY expression. Samples (six AF and six MP) were profiled using an miRNA Serum/Plasma Focus PCR Panel. Differentially expressed (DE) miRNAs were identified in AF (n = 5) and associated MP (n = 56) of male vs. female embryos (P < 0.05). Functional analysis showed that inflammatory and immune response were among the 13 biological processes enriched by miRNAs DE in MP in the male group (FDR < 0.05), suggesting that these sex-dependent DE miRNAs may be implicated in modulating the receptivity of the dam to a male embryo. Further, we compared the downstream targets of the sex-dependent DE miRNAs detected in MP with genes previously identified as DE in male vs. female genital ridges. The analyses revealed potential targets that might be important during this developmental stage such as SHROOM2, DDX3Y, SOX9, SRY, PPP1CB, JARID2, USP9X, KDM6A, and EIF2S3. Results from this study highlight novel aspects of sex determination and embryo-maternal communication in cattle such as the potential role of miRNAs in gonad development as well as in the modulation of the receptivity of the dam to a male embryo.
我们假设在与牛的性别决定和性腺分化过程相关的羊水 (AF) 和母体血浆 (MP) 中的 miRNA 表达中存在性别二态性差异。在受精后第 39 天屠宰时从六只怀孕的小母牛（三只为携带单个雄性胚胎，三只为携带单个雌性胚胎）中收集羊水和 MP。样本（六个 AF 和六个 MP）使用 miRNA 血清/血浆 Focus PCR 面板进行分析。在男性 vs. 女性胚胎的 AF（n=5）和相关 MP（n=56）中鉴定出差异表达（DE）的 miRNA（P<0.05）。功能分析表明，在男性组的 MP 中，炎症和免疫反应是 miRNA DE 富集的 13 个生物学过程之一（FDR<0.05），表明这些性别依赖的 DE miRNA 可能参与调节母体对雄性胚胎的接受度。此外，我们将在 MP 中检测到的性别依赖 DE miRNA 的下游靶基因与先前在男性与女性生殖嵴中鉴定为 DE 的基因进行了比较。分析揭示了在这个发育阶段可能很重要的潜在靶基因，如 SHROOM2、DDX3Y、SOX9、SRY、PPP1CB、JARID2、USP9X、KDM6A 和 EIF2S3。这项研究的结果突出了牛的性别决定和胚胎-母体通讯的新方面，例如 miRNA 在性腺发育以及调节母体对雄性胚胎的接受度方面的潜在作用。
