library_construction_protocol: The islets of Brd4 conditional knockout (PBKO) and control mice were isolated using  type XI collagenase and were dissociated using a trypsin EDTA solution for sequencing experiments. Single cell suspension was loaded onto a microfluidic chip and single cell RNA-seq libraries were constructed according to the manufacturer's instructions (Singleron GEXSCOPE Single Cell RNAseq Library Kit, Singleron Biotechnologies).