Linc-RAM is required for FGF2 function in regulating myogenic cell differentiation

ABSTRACTMyogenic differentiation of skeletal muscle stem cells, also known satellite cells, is tightly orchestrated by extrinsic and intrinsic regulators. Basic fibroblast growth factor (FGF2) is well documented to be implicated in satellite cell self-renewal and differentiation by repressing MyoD. We recently identified a MyoD-regulated and skeletal muscle-specifically expressed long non-coding RNA Linc-RAM which enhances myogenic differentiation by facilitating MyoD/Baf60c/Brg1 complex assembly. Herein, we investigated the transcriptional regulation and intracellular signaling pathway in mediating Linc-RAM gene expression during muscle cell differentiation. Firstly, we demonstrate Linc-RAM is negatively regulated by FGF2 via Ras/Raf/Mek/Erk signaling pathway in muscle cells. Overexpression of MyoD significantly attenuates repression of Linc-RAM promoter activities in C2C12 cells treated with FGF2. Knockout of MyoD abolishes FGF2-mediated repression of Linc-RAM gene transcription in satellite cells sorte...