Mating rapidly accelerates the rate of new DCG compartment formation.

<p><b>A, B</b>. Single z-plane images of SCs from 6-day-old virgin males labelled with GFP-GPI, either co-expressing (B) or not expressing (A) <i>dpp</i>-RNAi. Reducing Dpp signalling decreases the number of labelled DCGs (arrow). <b>C-E</b>. 6-day-old males were shifted to 28.5°C to induce GFP-GPI expression for 16 hrs in virgins (C) or immediately after (D) or before (E) mating. Their AGs were dissected and imaged; each image is from a single z-plane. <b>F</b>. Graph showing number of GFP-GPI-positive DCGs in SCs from either 6-day-old virgin or mated control flies or flies in which BMP signalling is inhibited. There is no decrease in total DCG number in SCs expressing either <i>dpp</i>-RNAi or <i>Dad</i> after mating. <b>G</b>. Graph showing GFP-positive DCG number after a 16 h pulse of GFP-GPI in SCs from 6-day-old males, as in C-E above. Genotypes for images are: <i>w; spi-GAL4 tub-GAL80</i>^<i>ts</i> <i>UAS-GFP-GPI</i> combined with no other transgene (A, and pulse-labelled in C, D, E) or <i>P[TRiP</i>.<i>HMS00011]attP2</i> (III) (B). The <i>w; spi-GAL4 tub-GAL80</i>^<i>ts</i> <i>UAS-GFP-GPI</i> line was used to generate data in F and G. ***P<0.001, Kruskal-Wallis test, n = 15. Scale bar for A-E, 10 μm.