Figure 2.

Endosome formation is induced early during necrosis. (A) Confocal images of touch receptor neurons expressing a p_mec-17APS-2::GFP reporter transgene. During early necrosis, the number of APS-2::GFP puncta, corresponding to clathrin-coated pits and vesicles, in touch receptor neurons of mec-4(d) animals does not change significantly, whereas at later stages it decreases. A similar decrease is also observed in unc-57(e1190) mutants, defective for clathrin-mediated endocytosis. (B) Confocal images of touch receptor neurons expressing a p_mec-7GFP::RAB-5 reporter transgene. The number of fluorescent puncta that correspond to early endosomes in touch receptor neurons of mec-4(d) animals significantly increases during early necrosis, whereas it declines later. (C) Confocal images of touch receptor neurons expressing a p_mec-7GFP::RAB-11 reporter transgene. The number of GFP::RAB-11 puncta that correspond to recycling endosomes in touch receptor neurons of mec-4(d) animals increases early during cell death, while it declines as degeneration proceeds. Both early and recycling endosomes tend to accumulate around a swollen structure that is probably the nucleus. Bars denote 4 μm. Error bars denote s.e.m. values (n>250 for all populations examined; P<0.001, compared with control animals, unpaired t-test).