Calcineurin promotes myogenic gene expression

We identified four major temporal patterns of Calcineurin (Cn)-dependent gene expression in differentiating myoblasts and determined that Cn is broadly required for the activation of the myogenic gene expression program. Cn promotes gene expression through direct binding to myogenic promoter sequences and facilitating the binding of BRG1 and other SWI/SNF subunit proteins as well as the binding of MyoD, a critical lineage determinant for skeletal muscle differentiation. We conclude that the Cn phosphatase directly impacts the expression of myogenic genes by promoting ATP-dependent chromatin remodeling and formation of transcription-competent promoters. Gene expression profiles of C2C12 cells treated with DMSO or FK506 at four time points growth, 0h, 24h, 72h in differentiation.