The RNAi screening was performed as described previously for the whole-genome and chromatin-library RNAi screening (20 (link),22 (link)). In brief, conjugation of LoriT-lin-53 (EPI300 bacteria) with the chromatin library (all in HT115 bacteria) was performed as described above. The conjugated clones were used to generate six-well RNAi NGM agar plates supplemented with 1mM IPTG and 50 μg/ml Carbenicilin. Plates were seeded with conjugated RNAi bacteria and Renilla luciferase (Rluc) RNAi was used as control. The CONJUDOR RNAi screen for germ cell reprogramming barriers was performed as an F1 screen using a standard RNAi feeding protocol (23 (link)). Screening was performed in duplicates using synchronized L1 animals which were grown at 15°C on normal food. After reaching the L4 larval stage animals were transferred to RNAi plates and grown on RNAi at 15°C until the F1 progeny reached the L4 stage. Subsequently, animals were heat-shocked at 37°C for 30 min and afterwards incubated at 25°C until the next day as described before (13 ,22 (link)). Plates were screened for presence of ectopic GFP in the germline using a fluorescence stereo microscope such as the M205 FCA (Leica) as described in previous studies to screen for this phenotype (10–12 (link),20 (link),22 (link)).