Untangling the placentome gene network of beef heifers in early gestation

The cotyledon and caruncle tissues provide a functional bridge between the fetus and the dam. However, the relationship between these tissues and the transcriptomic profile that underlies the tissue functions remains elusive. Herein we investigate the expression profile of cotyledon and caruncle from nulliparous beef heifers carrying female fetuses at day 83 of pregnancy to identify changes occurring across tissues that contribute to placental function and their tissue-specific roles. We identified 2654 differentially expressed genes [padj ≤ 0.05, abs(log2FC) ≥ 1], including nutrient transporters and paternally imprinted genes. We found key regulators of tissue function and differentiation, including FOXO4, GATA2, GATA3, and HAND1, rewired between the tissues. Finally, we shed light on the over-represented pathways related to immune tolerance, tissue differentiation and remodeling. Our findings highlighted the intricate and coordinated cross-talk between fetal-maternal tissues. They provided evidence of a fine-tuned gene regulatory network underlying pregnancy and tissue-specific function in the bovine placenta. •Genes involved with nutrient transport and tissue differentiation and remodeling were differentially expressed between the fetal and maternal tissues.•The Wnt pathway is likely repressed in cotyledon at day 83 of pregnancy.•Downregulated differentially expressed genes are involved with immune tolerance in the fetal placental tissue.•Key transcription factors play a key role in modulating gene expression between cotyledon and caruncle.•Paternally imprinted genes were upregulated in the cotyledon tissue.