Global profiling of protein lysine Malonylation during goat intramuscular Preadipocyte differentiation

Enhancing intramuscular fat (IMF) to improve the quality of livestock product has long been a goal in animal breeding. Recent studies have revealed a strong connection between malonylation and lipid metabolism, yet the function of malonylated proteins in ruminants largely unclear. In the present study, we identified the third day of goat intramuscular preadipocyte differentiation as a critical time point for lipid accumulation, with no significant alterations in malonylation levels. We identified 212 and 216 malonylated proteins on day 0 (d0) and day 3 (d3) of differentiation, respectively, enrichment in pathways such as glycolysis/gluconeogenesis, tight junctions, and actin cytoskeleton regulation. Our findings demonstrate the consistent presence of malonylation during preadipocyte differentiation, with minor quantitative variations, and highlight key malonylated proteins closely associated with lipid metabolism, including acetyl-CoA carboxylase (ACACA), translation control tumor protein 1 (TPT1), phosphoglycerate kinase 1 (PGK1), annexin A6 (ANXA6), and annexin A2 (ANXA2). Collectively, our study uncovers critical malonylated proteins during preadipocyte differentiation, establishing a foundation for exploring their roles in intramuscular fat deposition. SIGNIFICANCE: Currently, efforts are being made to improve meat quality by enhancing intramuscular fat (IMF) deposition, thereby promoting the development of the livestock industry. This study addresses a critical gap in our understanding of malonylation, a key post-translational modification, in livestock. By constructing the first malonylation protein modification map in goats and revealing dynamic changes during intramuscular preadipocyte differentiation, this research offers novel insights into the regulatory roles of malonylation in fat deposition. The findings not only advance the field of livestock proteomics but also provide a theoretical foundation for improving meat quality and exploring metabolic regulation in animals.