DNA methylation of the PLIN1 promoter downregulates expression in chicken lines

Abstract. Evidence suggests that Perilipin-1 ( PLIN1 ) is subject to functional regulation by epigenetic modifications in women with obesity. However, whether chicken PLIN1 expression is regulated by DNA methylation is unknown. Here, Sequenom MassARRAY and real-time polymerase chain reaction (PCR) were conducted to analyze the promoter methylation status and expression of the PLIN1 gene in Northeast Agricultural University broiler lines divergently selected for abdominal fat content. We found that chicken PLIN1 expression was significantly higher in adipose tissue of fat-line broilers than in lean lines at 1–7 weeks of age, and was significantly positively correlated with abdominal fat percentage (AFP) in chicken adipose development (Pearson's r =0.627 , P ). The region analyzed for DNA methylation was from −12 to −520  bp upstream of the translation start codon ATG, and had five CpG sites, where only the DNA methylation levels of CpG5 located at position −490  bp were significantly higher in lean compared to fat chickens at 5 and 6 weeks ( P ) and were significantly negatively correlated with PLIN1 mRNA levels and AFP ( P ). These results shed new light on the regulation of hypertrophic growth in chicken adipose development.