2.2. Plasmid and lentivirus production

In the study, sgRNAs were designed and constructed according to our previous study.12 Three sgRNA sequences used for each target gene promoter in the study are listed in Table S1. The lenti‐sgRNA (MS2)‐Puro backbone was purchased from Genomeditech Co. Ltd., lenti‐MS2‐P65‐HSF_Hygro and lenti‐dCas9‐VP64_Blast were provided by Addgene (#61426 and #61425), and the Hsd3b promoter driving green fluorescent protein (EGFP) was cloned into the pCDH‐CMV‐MCS‐EF1‐Puro vector (TranSheep Bio); all of these constructs were confirmed by sequencing.

For lentiviral production, in brief, the lentiviral vectors and two homologous helper plasmids were cotransfected into 293T cells through the FuGENE® 6 transfection reagent (Promega). The supernatants containing virus were harvested 48 hours or 72 hours post‐transfection and then concentrated through a centrifugal ultrafiltration device (Amicon Ultra 15 mL 100 K, Millipore).