Fig. 1: The Arp2/3 complex is required to regulate ring canal size throughout oogenesis.

(A) Maximum intensity projections of control and arpC2-RNAi egg chambers (stages 4/5, 6, and 7 are shown). Arrowheads indicate examples of small ring canals in the arpC2-RNAi egg chambers. (B) Magnified view of the ring canals indicated by the boxed regions in the stage 7 egg chambers in (A). Arrowheads indicate the three ring canals in each region; yellow arrowhead indicates a lumenless ring canal. (C) Box and whiskers plot showing the 10-90^th percent values for the diameter of ring canals connecting nurse cells. Individual points represent values outside of that range; lumenless ring canals were excluded from this analysis. n = 81-149 ring canals/stage for each condition. Asterisks indicate significant difference compared to control (p<0.05, K-S test). (D) Average number of normal and lumenless ring canals in the arpC2-RNAi egg chambers at each stage. In controls, all egg chambers contain 15 ring canals, all with a clear lumen. n=8-12 egg chambers per stage. Error bars represent SEM. (E) Box and whiskers plot showing the 10-90^th percent values for the volumes of mature eggs. n=44 eggs for control and n=38 eggs for arpC2-RNAi. Asterisk indicates significant difference compared to control (p<0.0001, 2-tailed t-test). Examples of mature eggs for each condition are shown. Scale bar is 100 μm. (F,G) Average fluorescence intensity of phalloidin and Hts-RC staining in ring canals of (F) stage 5 and (G) stage 10 control and arpC2-RNAi egg chambers (n=32 for control, n=39 for arpC2-RNAi in F; n=16 for control, n=17 for arpC2-RNAi in G). Error bars are SEM. Average full width at half maximum +/− SEM is shown for each stain in each condition. Examples of a single plane image of a ring canal for control (top) and arpC2-RNAi (bottom) at each stage are shown. Scale bars are 2 μm in F and 5 μm in G. For all experiments, ArpC2 was depleted throughout oogenesis using the maternal triple driver (MTD-GAL4).