12 h at 20°C. Neurodegeneration was assayed in the progeny of treated animals at the L1 stage of development. To simulate death-inducing hy- poxic conditions, we treated nematodes at the L4 stage of development with sodium azide (0.5 M for 30 min at 20°C; Sigma-Aldrich; adapted with modiﬁcations from Scott et al. [2002]). Statistical analysis of data was performed using Excel (Microsoft). Microscopy L1 stage mec-4(d) animals expressing LMP-1::GFP were stained with 1 μg/ml DAPI for 15 min after methanol ﬁxation. DAPI-stained animals were ob- served using a 40× objective (Plan-Neoﬂuar; Carl Zeiss MicroImaging, Inc.), 0.75, and a 365 ± 12–nm band-pass excitation/397-nm long- pass emission ﬁlter set. A microscope was used, and pictures were taken using a camera (AxioPlan and AxioCam, respectively; both Carl Zeiss MicroImaging, Inc.). For LMP-1::GFP imaging, animals were scanned with a 488-nm laser beam, under a confocal microscope (Radiance 2000; Bio-Rad Laboratories), using the LaserSharp 2000 software package (Bio-Rad Laboratories). Images of emission from individual PLM and ALM touch re- ceptor neurons were acquired using a 515 ± 15–nm band-pass ﬁlter and a 40× Plan-Neoﬂuar objective, 0.75. Acridine orange staining of necrotic cells was done by treating mec-4(d) early L1 larvae with 1 μM acri- dine orange for 20 min. To visualize stained cells, animals were scanned with a 543-nm laser beam. Images of emission from individual touch recep- tor neurons were acquired using a 590 ± 35–nm band-pass ﬁlter. Animals were mounted in a 2% agarose pad in M9 buffer containing 10 mM so- dium azide and observed at room temperature. Bright ﬁeld and epiﬂuores- cence images were merged using Photoshop (version 7.0.1; Adobe). 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