library_construction_protocol: RNA extraction was based on a method described by Phan[7] and his colleagues. The cells were washed twice before being resuspended in a 1:1 mixture of PBS and Drop-seq lysis buffer (Ficoll PM-400 6%, Sarkosyl 0.2%, EDTA 10 mM, Tris pH 7.5 200 mM, DTT 50 mM), supplemented with proteinase K. Samples were heat to 56°C for an hour (cross-link heat reversal) followed by incubation for 10 mins at RT followed by incubation on ice for at least 5 mins. The lysate was then combined with 350 uL of RLT plus buffer from RNeasy kit and processed according to the manufacturer's protocol. The RNA samples thus obtained were quantified and assessed for integrity using the 4200 TapeStation system (Agilent, Santa Clara, CA). RNA quality and concentration were assessed with a BioAnalyzer RNA-Seq Libraries were generated by using the NEBNext rRNA Depletion kit v2(Human/Mouse/Rat) followed by section 2 of the NEBNext® Ultra™ II Directional RNA Library Prep Kit for Illumina (NEB). RNA-Seq libraries were quantified by qPCR according to the Illumina Sequencing Library qPCR Quantification Guide and the quality of the libraries was evaluated on Agilent Bioanalyzer 2100 using the Agilent DNA-1000 chip. The RNA-Seq library sequencing was performed using Illumina Next-Seq500