Controls wing pigmentation patterning, possibly by regulating scale cell development (PubMed:27251284). Probably acts as an activator of the anaphase promoting complex/cyclosome (APC/C) that promotes the ubiquitin ligase activity and substrate specificity of the APC/C (By similarity). Highly expressed between the sixth larval instar (La6) and day 4 prepupa (Cr4), coinciding with a phase of rapid wing disk morphogenesis. Expression drops to a low level by day 6 prepupa (Cr6). Variations in cort gene cortex directly affect wing pigmentation patterning and are the cause of the darkening of the wing in the f. carbonaria strain. This phenomenon, known as industrial melanism, is a classroom example of evolution: during industrial revolution, the common pale B.betularia strain (f. typica) was replaced by a previously unknown black strain (f. carbonaria), driven by the interaction between bird predation and coal pollution. The variation is caused by insertion of a transposable element into the first intron of cort gene, which occured around 1819, in the early years of the industrial revolution. Belongs to the WD repeat CORT family. You want it darker - Issue 183 of September 2016