Fig. 8

Altered Arf6a activity can rescue autophagy phenotype in nrc^a14 cones. Fixed sections of 5 days post-fertilization A: wild type (WT) and B: nrc^a14 Tg(TαCP : GFP-map1lc3b) larvae transiently expressing Arf6a-tagRFPt construct in cones. WT Arf6a did not significantly affect the number of autophagosome in WT or nrc^a14 cones. Constitutively active Arf6a Q67L significantly rescued autophagosome defects nrc^a14 cones. Dominant negative guanosine diphosphate (GDP)-bound Arf6a T44N rescued the autophagy phenotype in nrc^a14 cones and decreased the number of autophagosomes in WT cones. Dominant negative phospholipase D-binding deficient Arf6a N48R also significantly rescued the autophagy defect in nrc^a14 cones. Arrowheads point to Arf6a expressing cells (magenta in merge). Scale bar = 2 µm in all images. Results were quantified by counting the number of total LC3 puncta in the Arf6a expressing cells and background corrected using the number of puncta in the non-Arf6a expressing cells in the same larvae. Graph in C shows average corrected LC3 puncta per cell. Error bars are SEM and n ≥ 50 cells for all conditions (exact n shown on graph) (*p-value < 0.05, ***p-value < 0.001 relative to cells not expressing Arf6a in nrc^a14, ^#p-value < 0.05 in WT, by one-way analysis of variance followed by Dunnett′s multiple comparison correction).