We followed STRT-seq steps (Islam et al., 2011 (link), 2014 (link)) to perform single-cell transcriptome amplification with a few modifications in the RT and amplification primers (Li et al., 2017 (link); Zhong et al., 2018 (link)). After amplification for 20 cycles, cDNAs labeled with different barcodes were pooled together and purified using the DNA Clean and Concentration Kit (ZYMO, D5044) to remove primer dimers and free primers. Thereafter, we performed a second amplification using biotin-labeled primers containing the Illumina read2 primer sequence and indexes for four cycles. The cDNAs were then fragmented by sonication with the Covaris S220 (ThermoFisher Scientific, 4465653) and the 5′ end of the first strand cDNA was enriched using C1 streptavidin beads (Invitrogen, 65002). A library was constructed using the KAPA Hyper Prep Kit from Illumina (KAPA, KK8505) according to the manufacturer’s instructions. 0.5 G of 150 bp pair-end reads were obtained for each single cell by sequencing on the Illumina Hiseq4000 as performed by Novogene.