library_construction_protocol: Cells were seeded to 15cm plates and lysed in NP-40 lysis buffer (Invitrogen) for 30 minutes on ice. Protein A/G beads (Invitrogen) were incubated with J2 antibody overnight at 4°C. Conjugated beads with J2 antibody were then incubated with the lysates for 2 hours at 4°C. The beads were then washed with high-salt PBS buffer (1x PBS, 0.1% Tween, 1M NaCl) once, followed by two washes with a low salt PBS buffer (1x PBS, 0.1% Tween, 0.5M NaCl). The immunoprecipitated samples were eluted from the beads using 1mg/ml Proteinase K (Thermo Fisher) in NP-40 lysis buffer.  The dsRNA was then polyadenylated using the methods provided by E. coli Poly A polymerase ( cat#: M0276L). PCR-cDNA libraries were prepared from ~100 ng of in vitro polyadenylated dsRNAs using the PCR-cDNA sequencing kit from Oxford Nanopore (ONT, catalog #: SQK-PCB114.24) and pooled as per the manufacturer's instructions. Sequencing was performed using R10.4.1 flow cells on a MinION Mk1B device and sequenced for 24 hours. Basecalling was performed using Dorado (version 7.9.8).