Fig. 6.

Epistatic model of red color pattern determination in H. erato. (A) Representation of the domain of potential optix expression, or window of expression, driven by optix enhancers in the epistatic model. (B) Visual representation of epistatic early patterning genes (shutters) repressing optix enhancer activity to refine red wing patterns. Broken dashed lines show the loss of CRE activity on optix, leading to a lack of red patterning. (C) Wild-type and WntA knockout butterflies (reprinted from ref. 20) exemplify the epistatic role of WntA on red scale patterning in H. e. demophoon. (D) Wild-type and obs214 mutant forewings and hindwings from the same mosaic H. erato individual show pleiotropic expansion of red distally from basal forewing and expansion outward of the hindwing rays. (E) H. melpomene mutant for obs214m with distal expansion of basal forewing red. Asymmetric expansion of red patterning is highlighted in panel below.