Abstract
Chicken meat represents the most widely consumed source of animal protein globally. The identification of non-coding RNAs (ncRNAs) that affect muscle development provides new selection targets for poultry breeding. In this study, muscle samples from high- and low-breast-weight chickens were collected and sequenced for long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), and mRNAs. Using weighted gene co-expression network analysis, we found 95 lncRNAs and 46 circRNAs that were significantly associated with breast muscle traits. Subsequently, 51 candidate lncRNAs and 22 candidate circRNAs were screened through differential expression analysis. Finally, by constructing an ncRNA-mRNA regulatory network and performing pathway enrichment analysis, we identified four lncRNAs (e.g., MSTRG.9172.1) and seven circRNAs (e.g., novel_circ_009419) as key regulatory molecules. Functional analysis revealed that these molecules modulate genes such as CD28, CCND2, TIAM1, and RRM2 through pathways including the actin cytoskeleton, p53 signaling pathway, and other pathways. In conclusion, this study provides clearer insight into the epigenetic regulatory network involved in chicken breast muscle development and offers important molecular markers for chicken genetic selection.