Figure 7.

Model for escape from silencing by the Kcnq1 gene. Enhancer candidates, depicted as purple circles, become active upon binding tissue-specific transcription factors (TF); ncRNA, wavy lines. (A) Appearance of enhancer-specific transcription factors promotes a conformational change that sequesters the Kcnq1 promoter from the effects of Kcnq1ot1. (B) Factors binding in intron 1 of Kcnq1 act as a boundary for the Kcnq1ot1 ncRNA on the paternal allele, leaving it available for tissue-specific activation by enhancer-binding regulatory proteins.