Plays a role of stimulator of transcription factors and nuclear receptors activities. Activates transcritional activity of estrogen receptor alpha, nuclear respiratory factor 1 (NRF1) and glucocorticoid receptor in the presence of glucocorticoids. May play a role in constitutive non-adrenergic-mediated mitochondrial biogenesis as suggested by increased basal oxygen consumption and mitochondrial number when overexpressed. May be involved in fat oxidation and non-oxidative glucose metabolism and in the regulation of energy expenditure. Induces the expression of PERM1 in the skeletal muscle in an ESRRA-dependent manner.