WING SURFACE INTERACTIONS IN VENATION PATTERNING IN DROSOPHILA

The adult wing of Drosophila consists of two wing surfaces apposed by their basal membranes which first came into contact following disc eve rsion at metamorphosis. Veins appear in these surfaces in a dorsal-ven tral symmetric pattern, but are 'corrugated' (vein cells are more comp acted and more pigmented) in a dorsal-ventral asymmetric pattern. We p revented dorsal-ventral contact apposition during wing imaginal disc m orphogenesis by implanting fragments of discs into metamorphosing host s. In these implants, longitudinal veins differentiate but with wider corrugation and in both surfaces. These results and those of genetic m osaics of mutants removing veins or causing ectopic veins reveal mutua l dorso-ventral induction/inhibition at work to modulate the final vei n differentiation pattern and corrugation. (C) 1997 Elsevier Science I reland Ltd.