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Fig. 8
dync1h1 and p150a/b mutants fail to phenocopy actr10 mutants.
(A) Wildtype larva at 4 dpf with full pLL axon extension into the tail. End of pLL nerve indicated by arrowhead. (B) Loss of DHC in dync1h1 mutants results in pLL axon degeneration, leading to a truncated pLL nerve at 4 dpf. Small eyes are also apparent (red dotted line), as has been reported previously. (C) p150a mutants have small eyes (red outline) but pLL nerves are identical to wildtype siblings. (D) p150b mutants at 4 dpf with normal pLL nerves and no change in eye diameter. (E) p150a/b double mutants have truncated, thin pLL nerves with swellings along the length of axons and in terminals and are indistinguishable from dync1h1 mutants. p150a/b mutants also show small eyes similar to dync1h1 and p150a mutants. (F,G) dync1h1 mutants display axon terminal swellings and mitochondrial accumulation compared to wildtype controls at 4 dpf. Arrows point to mitochondria rich, axonal swellings. Mitochondria are labeled by expression of mito-TagRFP (red on top F-J, white below F'-J'). (H,I) p150a and p150b single mutants have axon terminal morphology and mitochondrial localization in axon terminals similar to wildtype siblings. (J) Loss of both p150 paralogues (p150a/b; J) results in swollen axon terminals with increased mitochondrial density similar to dync1h1 mutants (G). (K–N) Kymograph analyses of mitochondrial transport in p150 mutants. (O) The proportion of mitochondria moving in both the anterograde and retrograde direction in pLL axons is significantly decreased in p150a/b double mutants (ANOVA with Tukey HSD post-hoc contrasts). (P) The number of mitochondria in pLL axons is decreased in p150a mutants compared to wildtype siblings (ANOVA with Tukey HSD post-hoc contrasts; *p<0.05). The number of mitochondria in pLL axons of p150a/b double mutants is dramatically reduced compared to wildtype siblings (ANOVA with Tukey HSD post-hoc contrasts; mean±SEM shown). (Q,R) Distance and velocity of limited residual mitochondrial movement is not significantly altered in p150a/b mutants compared to wildtype siblings (ANOVA with Tukey HSD post-hoc contrasts; mean ± SEM shown). Scale bars in A-E = 100 µm. Scale bars in F-J = 10 µm. Number of larvae assayed is indicated on graphs.