Figure S6 Characterization of LST-4-mediated phagosome acidification. (A) Representative DIC and fluorescence images of cell corpse staining by LysoSensor Green DND-189 in gla- 3(RNAi),
lst-4(
tm2423),
vps-18(
tm1125) and
vps-18(
tm1125);lst- 4
(tm2423) germ lines. Arrows point to germ cell corpses positive for LysoSensor Green DND-189; arrowheads indicate unstained corpses. Bars, 10 mm. (B) Quantification of cell corpse staining as shown in (A). $100 corpses were scored for each genotype. (C) Expression and localization of LST-4::GFP driven by the
lst-4 promoter. The transgenic array used is yqEx376 (Plst-4::lst- 4(gDNA)::gfp). LST-4::GFP is observed in ,100-cell stage embryos and in adult gonadal sheath cells. Bars, 10 mm. (D) Rescue of the cell corpse phenotype in
lst-4(
tm2423) mutants by Plst-4::lst- 4(gDNA)::gfp (yqEx376), Plst-4::
lst-4(cDNA)::gfp (yqEx368), and Plst- 4::
lst-4(cDNA)::mCherry (yqIs119). Germ cell corpses in one gonad arm were scored in each animal of the indicated strains at 36 h post L4 stage. For transgenes, the number of cell corpses in one transgenic line from a total of three lines exhibiting similar rescuing activity is shown. Error bars represent SEM. Comparisons were performed between
lst-4(
tm2423) and transgenic animals by unpaired t-tests. ** p,0.001. (E and F) Representative DIC and fluorescence images of germ cell corpse labeling by LST- 4::GFP (yqIs114) in mutants affecting engulfment (E) and animals with RNAi of genes required for phagosome maturation (F). Arrows indicate cell corpses labeled by LST-4::GFP and arrowheads indicate unlabeled corpses. Bars, 10 um.