Comparative transcriptomic and chromatin accessibility analysis of skeletal muscle satellite cells in Large White and Bama Xiang pigs

Porcine muscle satellite cells (PMSCs) play a crucial role in muscle growth and regeneration, with profound implications for improving pig breeding and meat production. This research combines RNA-seq and ATAC-seq to investigate molecular variations in PMSC function between Large White (LW) and Bama Xiang (Bama) pig breeds. The LW breed is known for its rapid growth and high lean meat yield, whereas Bama pigs exhibit higher intramuscular fat and superior meat flavor. Compared to Bama PMSCs, we found that LW PMSCs exhibited distinct chromatin accessibility landscapes, with selective increases in accessibility at genes associated with muscle development. Notably, this enhancement was prominent in genes critical for muscle development, such as CLEC14A, IGF2, and WNT10B , which are associated with the larger body size, faster growth, and higher lean meat percentage observed in LW pigs. In contrast, Bama PMSCs showed higher chromatin accessibility and expression levels for genes related to adipogenesis, including and ASCL2 , and SOX5 , which may contribute to the higher fat content and flavor profile of Bama pigs. These differences may be associated with transcription factor-mediated regulation and chromatin accessibility alterations, involving pathways related to Wnt signaling pathway, calcium signaling pathway, PI3K-Akt signaling pathway, and MAPK signaling pathway, thereby reflecting an integrated epigenetic-transcriptional mechanism underlying breed-specific muscle development. Our findings uncover the coordinated regulation of gene expression regulation and chromatin accessibility in breed-specific muscle development, providing insights into potential molecular targets for improving porcine meat production through breeding and cultured meat technologies.