library_construction_protocol: For each biological replicate, 100,000 cells were used to prepare ATACseq libraries following a modified protocol from Kaestner's lab (Ackermann et al., 2016). After the transposition reaction, using the Nextera DNA Library Prep Kit, DNA was isolated using a MinElute Reaction Cleanup Kit. To make the libraries, we used the NEBNext High-Fidelity 2X PCR Master Mix. Primers (universal and indexing) used are listed in Table 1. For multiplexing, we used the same universal primers for every sample, and every sample had their unique indexing primer. Quality control (QC) of the libraries was performed before sequencing using KAPA Library Quantification Kit for Illumina Platforms.