Lipid metabolism in early ontogeny of chickens and its genetic and epigenetic regulation

Lipid metabolism is a complex process critical for the development of the organism. In the early ontogenesis of chickens, starting from the incubation period and continuing into the neonatal period, there is an intensive accumulation and redistribution of lipids that provide energy and building material for the growing organism. This process is under the influence of paratypical factors and strict control of genetic and epigenetic mechanisms. Genetic regulation of lipid metabolism during this period is realized by a whole cascade of genes. The key role is played by genes encoding enzymes involved in lipolysis, lipogenesis, transport and metabolism of fatty acids. Transcriptomic studies analyzing gene expression at the mRNA level allow us to study these changes in developmental dynamics. However, genetic information is not the only factor determining lipid metabolism. Epigenetic mechanisms such microRNAs play a significant role in fine-tuning the expression of genes involved in fat metabolism. MicroRNAs are short noncoding RNAs that regulate the expression of target genes by affecting their mRNA stability and translation efficiency. They can interact with mRNAs of genes encoding key enzymes of lipid metabolism, altering their activity and, consequently, affecting lipid levels in blood and tissues. This review considers some aspects of lipid metabolism, the contribution of genetic and epigenetic components involved in the regulation of lipogenesis and adipogenesis during early ontogenesis of chickens.