FOXP3 and autoimmune disease: Furthermore, Satb1 deficiency from the DP stage on abrogates Treg-specific SE activation and Treg cell development and, as a consequence, induces severe autoimmune diseases.26 Satb1 and MLL4, an enzyme involved in enhancer priming, commonly occupy the newly identified conserved enhancer region, designated CNS0 at the Foxp3 locus, with subsequent activation of the enhancers at CNS3 and CNS2, and then the promoter.26,49