Evolution of Opsin Genes in Caddisflies (Insecta: Trichoptera)

Powell, A.; Heckenhauer, J.; Pauls, S. U.; Rios-Touma, B.; Kuranishi, R. B.; Holzenthal, R. W.; Razuri-Gonzales, E.; Bybee, S.; Frandsen, P. B.

doi:10.1101/2023.12.15.571940

bioRxiv · 10.1101/2023.12.15.571940

Evolution of Opsin Genes in Caddisflies (Insecta: Trichoptera)

Powell, A.·Heckenhauer, J.·Pauls, S. U.·Rios-Touma, B.·Kuranishi, R. B.·Holzenthal, R. W.·Razuri-Gonzales, E.·Bybee, S.·Frandsen, P. B.

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Abstract

Insects have evolved complex and diverse visual systems in which light-sensing protein molecules called opsins couple with a chromophore to form photopigments. Insect photopigments group into three major gene families based on wavelength sensitivity: long wavelength (LW), short wavelength (SW), and ultraviolet wavelength (UV). Here, we identified 123 opsin sequences from whole genome assemblies across 25 caddisfly species (Insecta: Trichoptera). We discovered the LW opsins have the most diversity across species and form two separate clades in the opsin gene tree. Conversely, we observed a loss of the SW opsin in half of the trichopteran species in this study, which might be associated with the fact that caddisflies are active during low-light conditions. Lastly, we found a single copy of the UV opsin in all the species in this study, with one exception: Athripsodes cinereus has two copies of the UV opsin and resides within a clade of caddisflies with colorful wing patterns. SignificanceWhile opsin evolution in some insect groups has been well-characterized, it has never been studied across caddisflies. Our findings provide insight into the diversity of opsins in caddisflies and form a basis for further research into the evolutionary drivers and complex visual systems in Trichoptera.

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Powell, A., Heckenhauer, J., Pauls, S. U., Rios-Touma, B., Kuranishi, R. B., Holzenthal, R. W., Razuri-Gonzales, E., Bybee, S., Frandsen, P. B.. 2023-12-16. Evolution of Opsin Genes in Caddisflies (Insecta: Trichoptera). https://doi.org/10.1101/2023.12.15.571940

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