Spot markings are often observed on caterpillars of butterflies and moths and used for aposematic coloration, but little is known about how the patterns are formed and repeatedly generated at each molt.
The research group of Prof. Haruhiko Fujiwara and Dr. Junichi Yamaguchi, at the Graduate School of Frontier Sciences of the University of Tokyo, has recently revealed the mechanisms of spot pattern formation on caterpillars of the silkworm, Bombyx mori and Bombyx mardarina, the silkworm mutant Multi lunar (L) and a swallowtail butterfly, Papilio machaon.
In these larvae, periodic expression of Wnt1, which is known to be an essential gene for various developmental processes, in response to a molting hormone ecdysteroid generates spot markings at each molt without majorly affecting other developmental processes.
This study has not only solved a riddle on the developmental mechanism how the spot markings are generated repeatedly on caterpillars but also shown that the research on the caterpillar markings offers a useful and impactful model for breakthroughs in evolutionary biology, developmental biology and ecology.
This achievement has been published in the online journal “Nature Communications” (May 14th).
Source: University of Tokyo