RNA was extracted using QIAGEN RNeasy kit. DNA after ChIP protocol was isolated using QIAGEN PCR purification kit. For ATAC-seq, frozen cells were thawed and washed once with PBS and then resuspended in 500 uL of cold ATAC lysis buffer. The cell number was assessed by Cellometer Auto 2000 (Nexcelom Bioscience). 50K to 100K nuclei were then centrifuge (pre-chilled) at 500 g for 10 min. Supernatant was then removed and the nuclei were resuspended in 50 uL of tagmentated DNA by pipetting up and down six times. The reactions were incubated at 37 °C for 30 min in a thermomixer shaking at 1,000 rpm, and then cleaned up by the MiniElute reaction clean up kit (Qiagen). ChIP-seq: ChIP-sequencing libraries were prepared using KAPA HyperPrep Kit (Kapa Biosystems) following manufacturer's recommendation. In brief, 500ng of input DNA sheared by Covaris LE220 ultrasonicator or 10 ng of immunoprecipitated DNA was end-repaired and 3'-dA tailed. Adapter was then ligated to the DNA, and ligated product was PCR amplified and cleaned up using SPRIselect Reagent (Beckman Coulter). for input and ip samples. Libraries were amplified using 13 cycles on the thermocycler. Post amplification libraries were size selected at 250- 450bp in length using Agencourt AMPure XP beads from Beckman Coulter. Libraries were validated using the Agilent High Sensitivity DNA Kit. RNA-sequencing libraries were prepared using the Illumina TruSeq Stranded Total RNA Preparation Kit with Ribo-Depletion. Input RNA quality was validated using the Agilent RNA 6000 Nano Kit. 200ng-1 µg of total RNA was used as starting material. Libraries were validated using the Agilent DNA 1000 Kit RNA-seq: Paramagnetic beads coupled with oligo d(T) are combined with total RNA to isolate poly(A)+ transcripts based on NEBNext® Poly(A) mRNA Magnetic Isolation Module manual. Prior to first strand synthesis, samples are randomly primed (5´ d(N6) 3´ [N=A,C,G,T]) and fragmented based on manufacturer's recommendation (NEBNext® Ultra™ II RNA Nondirectional Library Prep Kit for Illumina®). The first strand is synthesized with the Protoscript II Reverse Transcriptase with an longer extension period (40 minutes for 42◦C). All remaining steps for library construction were used according to the NEBNext® Ultra™ II RNA Nondirectional Library Prep Kit for Illumina®. Illumina 8-nt dual-indices were used. Samples were pooled and sequencing on a HiSeq with a read length configuration of 150 PE. ATAC-seq: Tagmentated DNA was amplified with barcode primers. Library quality and quantity were assessed with Qubit 2.0 DNA HS Assay (ThermoFisher, Massachusetts, USA), Tapestation High Sensitivity D1000 Assay (Agilent Technologies, California, USA), and QuantStudio® 5 System (Applied Biosystems, California, USA). Equimolar pooling of libraries was performed based on QC values and sequenced on an Illumina® HiSeq (Illumina, California, USA) with a read length configuration of 150 PE for 50M PE reads (25M in each direction) per sample.