Animals were washed off plates in M9, washed repeatedly until the M9 was clear, and nutated for 15 min to clear intestinal contents. Animals were then washed three additional times in M9 and once in water. After centrifugation and removal of excess liquid, 100 µL of worm suspension was added to 1 mL of Trizol (Thermo Fisher). Samples were stored at -80°C until RNA isolation. RNA extraction was performed as previously described (Weiser et al., 2017). Samples were freeze-thawed three times in liquid nitrogen prior to addition of 100 µL of 1-bromo-3-chloropropane and incubation at room temperature for 15 min. Samples were centrifuged at 4°C for 15 min and the aqueous phase collected. An equal volume of 100% isopropanol and 0.5 µL glycogen (1 mg/mL) were added, followed by incubation at -80°C for 2 h and centrifugation for 30 min at 4°C. RNA pellets were washed three times with 75% ethanol, air-dried, and resuspended in nuclease-free water. 2 µg total RNA was pretreated with RNA 5' polyphosphatase (Illumina) as described previously (Phillips et al., 2014). Pretreated RNA was used for small RNA library preparation with the NEBNext Multiplex Small RNA Library Prep kit according to the manufacturer's instructions.