Fig. 1

Directional growth of primary dendrites in ddaE neuron is deficient in wg ^l-12 mutant. a Wg is expressed at the posterior side of the dorsal cluster of da neurons in whole mount fly embryos. Wg expression pattern (green) is monitored by UAS- mCD8-eGFP under the control of wg-Gal4. The da neurons (red) are stained by antibody 22C10. White brackets indicate the regions of thorax and abdomen. a ’, Enlarged view of AS4-6 (white square in a). White broken lines 1–3 indicate the positions of X-Z or Y-Z section images 1–3, respectively. Red broken lines indicate the ddaE neurons and green broken lines indicate the Wg-expression cells. b Pseudo-color image shows that Wg-expressing cells are localized mainly in the dorsal-posterior region relative to ddaE neuron in w ¹¹¹⁸ AS. c The initial 20 μm parts of primary dendrites shift towards AP axis in wg ^l-12 mutants. Left panels show the trajectory of primary dendrites of ddaE in the 3^rd instar larvae. Red circles indicate the circle around the soma with a radius of 20 μm. The enlarged view of the intersections of the circle and the trajectory of primary dendrites are shown in right panels. Blue dots and red dots indicate the dorsal intersections and ventral ones, respectively. The Blue arrows and red arrows indicate the average direction of dorsal and ventral primary dendrites, respectively. A, P, D and V indicates the direction of anterior, posterior, dorsal and ventral, respectively. (n = 24–50). d-e PD-Angle significantly decreased in wg ^l-12 mutants. d Representative images of ddaE neurons in wild type w ¹¹¹⁸ and wg ^l-12 mutant at third instar larvae stage. Gal4^2–21, UAS-mCD8-eGFP was used to visualize the entire neuron. e Quantification statistic of PD-Angle in wild type w ¹¹¹⁸ and wg ^l-12 mutant. (n = 24–50). f-g The PD-Angle is decreased in wg ^l-12 mutants at embryonic stage 17. (n = 35-57). Scale bars, 50 μm in (a and d) and 20 μm in (a ’ and f). In all figures, representative images are shown in anterior left and dorsal up; white broken rectangles indicate the position of the inset in the upper-right corner, and red arrows indicate the initial growth direction of the two primary dendrites. *p < 0.05, **p < 0.01, ***p < 0.001, and N.S. indicates no significant changes