Genome size evolution in the diverse insect order Trichoptera
Affiliation
Department of Ecology and Evolutionary Biology, University of ArizonaIssue Date
2022Keywords
biodiversityde novo genome assembly
genome duplication
genome size evolution
genomic diversity
genomics
insects
repetitive elements
transposable elements
Trichoptera
Metadata
Show full item recordPublisher
Oxford University PressCitation
Heckenhauer, J., Frandsen, P. B., Sproul, J. S., Li, Z., Paule, J., Larracuente, A. M., Maughan, P. J., Barker, M. S., Schneider, J. V., Stewart, R. J., & Pauls, S. U. (2022). Genome size evolution in the diverse insect order Trichoptera. GigaScience.Journal
GigaScienceRights
Copyright © The Author(s) 2022. Published by Oxford University Press GigaScience. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/).Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
Background: Genome size is implicated in the form, function, and ecological success of a species. Two principally different mechanisms are proposed as major drivers of eukaryotic genome evolution and diversity: polyploidy (i.e., whole-genome duplication) or smaller duplication events and bursts in the activity of repetitive elements. Here, we generated de novo genome assemblies of 17 caddisflies covering all major lineages of Trichoptera. Using these and previously sequenced genomes, we use caddisflies as a model for understanding genome size evolution in diverse insect lineages. Results: We detect a ∼14-fold variation in genome size across the order Trichoptera. We find strong evidence that repetitive element expansions, particularly those of transposable elements (TEs), are important drivers of large caddisfly genome sizes. Using an innovative method to examine TEs associated with universal single-copy orthologs (i.e., BUSCO genes), we find that TE expansions have a major impact on protein-coding gene regions, with TE-gene associations showing a linear relationship with increasing genome size. Intriguingly, we find that expanded genomes preferentially evolved in caddisfly clades with a higher ecological diversity (i.e., various feeding modes, diversification in variable, less stable environments). Conclusion: Our findings provide a platform to test hypotheses about the potential evolutionary roles of TE activity and TE-gene associations, particularly in groups with high species, ecological, and functional diversities. © 2022 The Author(s) 2022. Published by Oxford University Press GigaScience.Note
Open access journalISSN
2047-217XPubMed ID
35217860Version
Final published versionScopus Count
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Except where otherwise noted, this item's license is described as Copyright © The Author(s) 2022. Published by Oxford University Press GigaScience. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/).
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