Adipogenesis and myogenesis transcriptome in Piau local breed conceptuses and its comparison with Commercial pig data

The growth and development of skeletal muscle, along with intramuscular fat deposition, determine the quantity and quality of pork. The Brazilian Piau breed, which has not undergone genetic improvement, exhibits slower growth, greater fat deposition, and increased disease resistance compared to Commercial lines, making it a valuable genetic resource and a relevant model for studying the molecular regulation of myogenesis and adipogenesis. This study aimed to analyze RNA sequencing (RNA-seq) data from Piau pigs to identify differentially expressed genes and biological processes during two stages of intrauterine development, at 25 and 35 days of gestation. Furthermore, gene expression profiles of Piau conceptuses were compared to those of a Commercial line to investigate transcriptional differences between genetic groups. RNA-seq data from seventeen Piau conceptuses (8 embryos and 9 fetuses) were analyzed and compared with public data from a Commercial pig line (Large White × Landrace × Duroc). Differential expression analysis was performed in R, considering FDR < 0.05 and |log2FC| ≥ 2.0, and functional enrichment was evaluated in Cytoscape. In the Piau breed, 43 gene ontology terms showed significant enrichment, mainly related to myogenesis and adipogenesis. In the Commercial breed, 65 enriched terms were identified, predominantly associated with myogenesis. In total, 41 genes showed differential expression in Piau and 55 in Commercial between gestational stages. Key genes associated with adipogenesis and myogenesis were identified, some with functions dependent on the genetic group. These findings contribute to the understanding of molecular differences between genetic groups and support future breeding strategies.