MYLK4 and myopathy: The ryanodine receptor 1 (RYR1) is a major component of the calcium release complex, which mediates calcium efflux from the sarcoplasmic reticulum into the cytosol and in vivo knockdown and mutations of RYR1 lead to severe myopathies.S45 Other putative targets including myosin light chain kinase 4 (MYLK4) and myomesin 1 (MYOM1) are downstream of the androgen receptor (AR) and mediate its effects on force production.S46 The spermine oxidase gene (SMOX), another important target of the AR in muscleS47, S48 is downregulated by Nr2f6 overexpression and upregulated by Nr2f6 silencing.