Molecular basis of wax-based color change and UV reflection in dragonflies
Abstract
Many animals change their body color for visual signaling and environmental adaptation. Some dragonflies show wax-based color change and ultraviolet (UV) reflection, but biochemical properties underlying the phenomena are totally unknown. Here we investigated the UV-reflective abdominal wax of dragonflies, thereby identifying very long-chain methyl ketones and aldehydes as unique and major wax components. Although little wax was detected on young adults, dense wax secretion was mainly found on the dorsal abdomen in mature males of Orthetrum albistylum and O. melania, while pruinose wax secretion was identified on the ventral abdomen in mature females of O. albistylum and Sympetrum darwinianum. Comparative transcriptomics demonstrated drastic upregulation of ELOVL17 gene, a member of the fatty acid elongase family, whose expression reflected the distribution of very long-chain methyl ketones. Synthetic 2-pentacosanone, the major component of dragonfly's wax, spontaneously formed light-scattering scale-like fine structures with strong UV reflection, suggesting its potential utility for biomimetics.
Data availability
The sequences reported in this paper have been deposited in the DNAData Bank Japan Read Archive, www.ddbj.nig.ac.jp (accession nos. BR001497-BR001513, LC416747-LC416767, DRA001687, DRA001690, DRA001693-DRA001694, DRA001697-DRA001698, DRA001700-DRA001701, DRA001703-DRA001704, DRA001706-DRA001707, DRA001709-DRA001710, DRA001712-DRA001713, DRA001716-DRA001717, DRA007015-DRA007018).All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 2,6I-L,7I-N, and Figure S1.
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Ladona fulva genome sequencingNCBI Nucleotide, APVN00000000.2.
Article and author information
Author details
Funding
Japan Society for the Promotion of Science (JP26660276)
- Ryo Futahashi
Genome research for BioResource NODAI Genome Research Center
- Ryo Futahashi
- Ryouka Kawahara-Miki
- Shunsuke Yajima
Japan Society for the Promotion of Science (JP18H02491)
- Ryo Futahashi
Japan Society for the Promotion of Science (JP18H04893)
- Ryo Futahashi
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Futahashi et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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