Figure 3. Function of Netrins in peripheral dendritic targeting and expression of Netrin-B.

(A–D) Analysis of targeting of class III da neuron ddaA (marked by 189Y-Gal4, UAS-mCD8::GFP) in (A) WT (n=13), (B) NetAB^Δ (n=7), (C) NetA^Δ (n=7) and (D) NetB^Δ (n=13) third instar larvae. A–D show representative images of area surrounding LF. The location of the chordotonal organ, labeled in the HRP channel (not shown), is indicated by a yellow line, and the region corresponding to LF indicated by a yellow circle. Targeting is disrupted in NetAB^Δ and NetB^Δ mutant larvae.

(E) The distances of the closest major branch tip to LF in WT, NetAB^Δ, NetA^Δ, and NetB^Δ animals.

(F) NetB^tm levels are highly enriched in the chordotonal organ of third instar larvae (arrowheads).

(G) Quantification of closest tip to LF in ΔNetA,NetB^myc (n=10) and ΔNetA,NetB^tm (n=17) larvae.

(H) Morphology and chordotonal organ targeting of single wild-type FLP-out clone of ddaA.

(I) Lack of chordotonal targeting of ddaA neuron as revealed by a single FLP-out clone expressing Unc5 under the control of 109(2)80-Gal4.

(J) Plot of the closest branch tip to LF in wild-type (WT, n=10) and UAS-Unc5-expressing (n=6) ddaA neurons.

All scale bars = 50μm.

Datasets are presented in boxplots as median (thick line), quartiles Q1–Q3 (25%–75% quantiles; shaded box), and data in 1.5× quartile range (dashed bars). Data points outside these ranges are indicated as open circles.

* = p < 0.05; ** = p < 0.01; *** = p < 0.001 by Wilcoxon rank-sum test

See also Supplemental Figure S3