Astrocyte-derived signals converge with intrinsic BeatVa _M neuron EcR signaling to execute local pruning. (A and B) Beat-Va_M neurons labeled with MCFO in an alrm-LexA background (control) at wL3 (A) or HE (B). (C and D)alrm-LexA, LexAOp-EcR^DN background labeled with the MCFO technique at wL3 (C) or HE (D). (E and F) Quantification of branch point number (E) or total neurite length (F) of A–D. (G and H) Beat-Va_M neurons in an alrm-Gal4 background (control) at wL3 (G) or HE (H). (I and J) Beat-Va_M neurons in an alrm-Gal4, UAS-EcR^DN background at wL3 (I) or HE (J). (K and L) Quantification of branch point number (K) or total neurite length (L) of G–J. (E and F) Each data point represents one cell. wL3 control cells were imaged from six animals, HE control cells were imaged from six animals, wL3 astrocyte+neuron EcRDN cells were imaged from six animals, and HE astrocyte EcRDN cells were imaged from six animals. (J and K) Each data point represents one cell. wL3 control cells were imaged from six animals, HE control cells were imaged from five animals, wL3 astrocyte EcRDN cells were imaged from seven animals, HE astrocyte EcRDN cells were imaged from six animals. All comparisons are done with two-way ANOVA with the Sidak test for multiple comparisons. (A–D and G–J) Surface renderings. Intact neurites, magenta; fragmented neurites, cyan. Scale bars are 20 µm for whole neuron images and 5 µm for magnified images. Colored data points correspond to the representative image shown in the figure. All error bars are SEM.