LAUSR

not been provided. In this study, we isolated three genes in this conservative region, by positional cloning of a melanism mutant (sml) in silkworm, Bombyx mori. The expression level of these gens was significantly lower in the sml mutant compared to the wild-type from the 1 day of pupal stage to moth, and knockdown of them in wild-type, respectively, resulted in scale melanization of moths. We also found that the sml allele likely had impacts on the genes (such as yellow and laccase2) of melanin biosynthesis. Furthermore, a reduction of diversity (ROD) analysis and Tajima'D test in the genome data of B. mori and B. Mandarina revealed the strong domestication selection of the sml region. Our findings provide functional evidences for the notion that multiple genes in the conservative color-patterning genomic region influenced pigmentation of lepidopteran insects, and further extend our understanding of the mechanism underlying the pigmentation of the lepidopteran insects.