GLR-1::GFP fluorescence in (A) wild-type animals, (B) pmk-1(km25) mutants, and (C) pmk-1(km25) mutants containing a transgene that expresses dominant negative RAB-5 with a GDP-locked mutation. Yellow arrows indicate elongated accumulations. Bar: 5 μm. Average GLR-1::GFP number is quantified as (D) puncta or (E) accumulations per length of ventral cord dendrites. (F, J, N) GLR-1::GFP and (G, K, O) mRFP::SYX-7 fluorescence observed in the PVC neuron cell body of (F, G, H, I) wild type, (J, K, L, M) sek-1 mutants, and (N, O, P, Q) pmk-1 mutants. (H, L, P) Merged image of the red and green channels. (I, M, Q) Binary image with white indicating pixels with significant signal (colocalization) in both channels. (R) Fraction of GLR-1::GFP-labeled pixels that overlap with mRFP:SYX-7-labeled pixels. Graph bar columns labeled with asterisks indicate statistical difference by ANOVA followed by Dunnett’s multiple comparison to wild type (****p<0.0001, ***p<0.001, **p<0.01, *p<0.05). Lines connecting specific columns indicate pairwise comparisons using the Holm-Šídák test. Error bars indicate SEM. N = 13–16 animals per genotype.