Effect of expression of PPARG, DNM2L, RRAD, and LINGO1 on broiler chicken breast muscle satellite cell function

Disorders affecting the breast muscle of modern commercial broiler chickens have increased in recent years. Wooden Breast (WB) myopathy is characterized by a palpably hard breast muscle with increased fat deposition. WB is a metabolic disorder with lipid accumulation considered to be a primary causal factor. The adult myoblasts, satellite cells, are a partially differentiated stem cell population and primarily function in muscle growth and regeneration. The satellite cells also express adipogenic genes. The objective of this study was to determine the expression of the adipogenic genes PPARG, DNM2L, RRAD, and LINGO1 in commercial Ross 708 (708) and Randombred (RBch) satellite cells. RBch satellite cells are from commercial 1995 broilers before WB and 708 broilers are a modern commercial line. In general, expression of these genes was different between the 708 and RBch satellite cells during proliferation and differentiation. Expression of PPARG and RRAD were both significantly increased during both proliferation and differentiation in the 708 cells (P ≤ 0.05). Knocking down the expression of these genes with small interfering RNAs did not greatly affect either proliferation or differentiation. Lipid accumulation was affected by the knockdown of these genes with significant line effects from 48 h of proliferation through 72 h of differentiation. In general, 708 satellite cells had higher lipid levels. Knockdown treatment effect was specific to each gene. The results demonstrate that lipid biosynthesis has been affected in breast muscle satellite cells which may contribute to the increased lipid deposition in modern day commercial broiler chickens.