Constrictive behaviour of boundary LEC at the beginning of histoblast nest expansion, early during morphogenesis. Sqh::GFP labels cell-cell interfaces. Also, some diffuse labelling in the apical cell area, but no actin foci are visible. LEC constricts over time. Scale bar, 10 μm; a, anterior; p, posterior; m, medial (corresponds to dorsal); l, lateral (corresponds to ventral).