Fig. 1

Hypothetical models to explain sense and antisense pancRNA (AS pancRNA) activities. a pancRNAs act in concert with PARP1 and TET3 factors to establish the hypomethylated state of CpG islands within the promoter, thus activating in cis the transcription of the host gene. b AS pancRNAs recruit Polycomb repressive complex PRC2, catalyzing the trimethylation of histone H3 at K27 and the chromatin packaging. c AS pancRNAs can bind histone acetylases and methylases that open the chromatin, allowing the engagement of the Mediator Complex and the chromatin looping. d Antisense pancRNAs tight on the promoter an epigenetic silencing complex formed by Ago-1, DNMT3a, EZH2, Suv39H1 and HDAC1, which causes trimethylation of histone H3 at K27, heterochromatin formation and repression of transcription. e pancRNAs can bind RNA binding proteins (including FUS/TLS and Sam68), thus promoting inhibition of the histone acetyltransferase activity of the p300/CREB binding protein (CBP)-associated factor (PCAF) and resulting in the suppression of transcription