C. elegans Pathogen Avoidance Assay

C. elegans were cultivated and strains constructed using standard methods^{27 (link)}. Transgenic strains were generated using indicated constructs and standard microinjection methods^{28 (link)}. MosSCI single-copy insertions were generated as described^{29 (link)}. Assays measuring C. elegans pathogen avoidance behaviour utilized P. aeruginosa PA14 plates prepared as follows: a 100 mL solution of LB was inoculated with a single colony of P. aeruginosa PA14 and grown overnight without shaking at 37°C (OD=0.2-0.3). 30 μL of this culture was used to seed the center of each 100-mm NGM plate, and the seeded plates were incubated for 24 h at room temperature (22.5°C). Approximately 30 Larval Stage 4 (L4) animals were transferred onto plates containing the P. aeruginosa PA14 lawn at 22.5°C, and occupancy was determined at the indicated times. Survival assays were carried out on 35 mm Slow-Killing Assay plates^{30 (link)} supplemented with 5-fluorodeoxyuridine (0.05 mg/mL) and seeded with P. aeruginosa PA14 prepared as above and maintained at 22.5°C. Laser ablations were performed on L3-stage larvae as described in text. Microscopy and image analysis was carried out on an AxioImager Z1 fluorescence microscope fitted with CCD camera (AxioCam) and processed with Axioplan image processor software (Zeiss). The statistical analyses were performed using GraphPad Prism software.