Horizontal Transfer of Bacterial Cytolethal Distending Toxin B Genes to Insects

Authors

Kirsten I. Verster, University of California, Berkeley
Jennifer H. Wisecaver, Prudue University
Marianthi Karageorgi, University of California, Berkeley
Rebecca P. Duncan, University of California, Berkeley
Andrew D. Gloss, University of Chicago
Ellie E. Armstrong, Stanford University
Donald K. Price, University of Nevada, Las VegasFollow
Aruna R. Menon, University of California, Berkeley
Zainab M. Ali, University of California, Berkeley
Noah K. Whiteman, University of California, BerkeleyFollow

Document Type

Article

Publication Date

6-25-2019

Publication Title

Molecular Biology and Evolution

Volume

36

Issue

10

First page number:

2105

Last page number:

2110

Abstract

Horizontal gene transfer events have played a major role in the evolution of microbial species, but their importance in animals is less clear. Here, we report horizontal gene transfer of cytolethal distending toxin B (cdtB), prokaryotic genes encoding eukaryote-targeting DNase I toxins, into the genomes of vinegar flies (Diptera: Drosophilidae) and aphids (Hemiptera: Aphididae). We found insect-encoded cdtB genes are most closely related to orthologs from bacteriophage that infect Candidatus Hamiltonella defensa, a bacterial mutualistic symbiont of aphids that confers resistance to parasitoid wasps. In drosophilids, cdtB orthologs are highly expressed during the parasitoid-prone larval stage and encode a protein with ancestral DNase activity. We show that cdtB has been domesticated by diverse insects and hypothesize that it functions in defense against their natural enemies.

Keywords

Horizontal gene transfer; Cytolethal distending toxin; Aphids; Drosophila; DNase

Disciplines

Entomology | Genetics and Genomics

Language

English

Repository Citation

Verster, K. I., Wisecaver, J. H., Karageorgi, M., Duncan, R. P., Gloss, A. D., Armstrong, E. E., Price, D. K., Menon, A. R., Ali, Z. M., Whiteman, N. K. (2019). Horizontal Transfer of Bacterial Cytolethal Distending Toxin B Genes to Insects. Molecular Biology and Evolution, 36(10), 2105-2110.
http://dx.doi.org/10.1093/molbev/msz146