Escherichia coli dh5 α cells

Three strains of B. bassiana were randomly selected from each different collection site confirmed to be infected by virus BbCV2 by dsRNA extraction and RT-PCR. Three pairs of primers (Additional file 2: Table S2) were designed for full-length amplification of nucleotide sequences of the RNA-dependent RNA polymerase (RdRp) gene of virus BbCV2 (GenBank no. MW314841.1). Products obtained by RT-PCR amplification were extracted from 1% agarose electrophoresis gels, cloned using a TA/Blank Zero Cloning Kit (Vazyme, Nanjing, China), transformed into competent Escherichia coli DH5-α cells (Vazyme) by heat shock, and sequenced by Sangong Bioengineering Co. Ltd. (Shanghai, China). The complete sequence of the BbCV2 RdRp gene was obtained by splicing using DNAstar7.1 (DNASTAR, Inc., Madison, USA) and DNAMAN version 9 (Lynnon Biosoft, Vaudreuil, Canada). Modification and splicing of the measured cDNA gene sequence were assessed using Snap Gene 6.0.2 (Dotmatics Ltd, Windhill, UK) and DNAMAN (LynnonBiosoft, Vaudreuil, Canada) 9. MEGA11 (Mega Limited, Auckland, New Zealand) and DNAsp5 (University of Barcelona, Barcelona, Spain) were used to construct a phylogenetic tree of virus BbCV2 in the selected B. bassiana strains collected from different locations in Jilin Province, and the genetic distance was calculated.

The coding sequence of YTHDF1 mRNA and UHRF1 mRNA was PCR amplified, digested with EcoRI and BamHI, and ligated to vector pLVX‐CMV‐EGFP‐T2A‐PuroR as pLVX‐YTHDF1 and pLVX‐UHRF1. shYTHDF1 oligonucleotides were annealed and ligated into the vector pSIH‐H1‐copGFP‐T2A‐Puro as pSIH‐shYTHDF1‐1/‐2. The ligated products were transformed into competent Escherichia coli DH5α cells (Vazyme, Nanjing, China), cultured, and extracted with the QIAGEN EndoFree™ Plasmid Extraction Kit (12362, QIAGEN, Germany). pLVX‐YTHDF1, pLVX‐UHRF1, pSIH‐shYTHDF1‐1/2 together with psPAX2, pMD2.G was transfected by polyethyleneimine linear (PEI) (MW = 40,000, Sigma), respectively, as described previously.
²¹ (link) After 48 h, supernatants from the cultures were collected and mixed with 0.4 M NaCl and 12% PEG‐6000 overnight, followed by centrifugation at 6000×g for 15 min. Virus pellets were resuspended by 200 μL 1× PBS for further use. The oligonucleotides used in this study was listed in Table S2.