The Transcriptional Landscape of the Early Embryonic Developmental Biology in Hulunbuir Short-Tailed Sheep

Abstract

Background: Since both fetal and postnatal development is determined by early embryonic development and the molecular mechanism and organogenesis process of early mouse embryos have been thoroughly studied. However, the specific development process of early embryos in Mongolian sheep remains poorly understood. Methods: The 16-day and 25-day embryo samples of Inner Mongolia Hulunbuir short-tailed sheep were evaluated by transcriptome sequencing technique and the genes with significant differences were screened and the gene function was enriched by gene ontology (GO) database and Kyoto Encyclopedia of Gene and Genome (KEGG) database. Result: A total of 4348 differentially expressed genes (DEGs) were analyzed by sequencing and especially significant DEGs included the genes such as COL6A2, COL4A4, LAMA4, ITGA8, FN1 involved in ECM-receptor interaction, focal adhesion, PI3K-Akt signaling and protein digestion and absorption pathways; YAP1, FZD4, TGFB1, WNT2, BMP5, BMP2, WNT11 involved in Hippo signaling pathway. In pathway analysis, those pathways mainly related to cell interaction and organogenesis were highlighted at the E16 stage. They are critical for transcriptional control in early embryonic development, especially during organ building. The genes that make organs and body structures more complex and detailed and those related to the development of brain, liver and immune system are enriched for the E25 stage. Therefore, this study provides important supplementary and exploratory reference data for the further research on early embryonic development in sheep.