Butterfly wings shaped by a molecular cookie cutter: evolutionary radiation of lepidopteran wing shapes associated with a derived Cut/wingless wing margin boundary system.

Butterflies and moths show a remarkable diversity of specialized wing shapes, yet little is known about the molecular basis of wing shape determination. To learn more about this process we examined the expression of dorsoventral (DV) boundary candidate genes in developing wings of several species of Lepidoptera. We found that the transcription factor Cut and mRNA for the signaling molecule wingless (wg) are strongly co-expressed in a discrete zone around the larval wing disc margin.