Abstract
Marek's disease (MD), induced by the highly contagious Marek's disease virus (MDV), remains a significant challenge to global poultry health despite extensive vaccination efforts. This study employed integrated transcriptomic and metabolomic analyses to investigate liver responses in naturally MDV-infected Wenchang chickens during late infection stages. RNA sequencing identified 959 differentially expressed genes (DEGs) between the infected and uninfected groups. Functional enrichment analysis demonstrated that these DEGs were primarily associated with canonical pathways related to metabolism and cellular processes, including lipid, carbohydrate, and amino acid metabolism, as well as the p53 signaling pathway, cell cycle, and apoptosis. Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) detected 561 differentially expressed metabolites (DEMs), showing near-significant enrichment (p = 0.069) in phenylalanine metabolism. Integrated analysis of transcriptomics and metabolomics data highlighted that critical gene-metabolite pairs such as SGPL1-palmitaldehyde-sphinganine-1-phosphate and ME1-NADP+-malic acid potentially mediate functional crosstalk between sphingolipid metabolism and cellular redox homeostasis during viral oncogenesis. This comprehensive mapping of regulatory networks provides insights into host-virus interactions during MDV pathogenesis, offering potential applications in immunomodulation approaches, targeted therapeutic strategies, and vaccine adjuvant development.