The Transmission Patterns of the Endosymbiont Wolbachia within the Hawaiian Drosophilidae Adaptive Radiation

Renée L Corpuz; M Renee Bellinger; Anne Veillet; Karl N Magnacca; Donald K Price

doi:10.3390/genes14081545

The Transmission Patterns of the Endosymbiont Wolbachia within the Hawaiian Drosophilidae Adaptive Radiation

Genes (Basel). 2023 Jul 27;14(8):1545. doi: 10.3390/genes14081545.

Authors

Renée L Corpuz¹, M Renee Bellinger^{1

2}, Anne Veillet¹, Karl N Magnacca³, Donald K Price^{1

4}

Affiliations

¹ Department of Biology, Tropical Conservation Biology and Environmental Science, University of Hawaii at Hilo, 200 West Kāwili Street, Hilo, HI 96720, USA.
² U.S. Geological Survey, Pacific Island Ecosystems Research Center, P.O. Box 44, Hawaii National Park, HI 96718, USA.
³ Department of Land and Natural Resources, Division of Forestry & Wildlife, Native Ecosystem Protection and Management, Hawaii Invertebrate Program, 1151 Punchbowl Street Rm. 325, Honolulu, HI 96813, USA.
⁴ School of Life Sciences, University of Nevada, Las Vegas, NV 89557, USA.

Abstract

The evolution of endosymbionts and their hosts can lead to highly dynamic interactions with varying fitness effects for both the endosymbiont and host species. Wolbachia, a ubiquitous endosymbiont of arthropods and nematodes, can have both beneficial and detrimental effects on host fitness. We documented the occurrence and patterns of transmission of Wolbachia within the Hawaiian Drosophilidae and examined the potential contributions of Wolbachia to the rapid diversification of their hosts. Screens for Wolbachia infections across a minimum of 140 species of Hawaiian Drosophila and Scaptomyza revealed species-level infections of 20.0%, and across all 399 samples, a general infection rate of 10.3%. Among the 44 Wolbachia strains we identified using a modified Wolbachia multi-locus strain typing scheme, 30 (68.18%) belonged to supergroup B, five (11.36%) belonged to supergroup A, and nine (20.45%) had alleles with conflicting supergroup assignments. Co-phylogenetic reconciliation analysis indicated that Wolbachia strain diversity within their endemic Hawaiian Drosophilidae hosts can be explained by vertical (e.g., co-speciation) and horizontal (e.g., host switch) modes of transmission. Results from stochastic character trait mapping suggest that horizontal transmission is associated with the preferred oviposition substrate of the host, but not the host's plant family or island of occurrence. For Hawaiian Drosophilid species of conservation concern, with 13 species listed as endangered and 1 listed as threatened, knowledge of Wolbachia strain types, infection status, and potential for superinfection could assist with conservation breeding programs designed to bolster population sizes, especially when wild populations are supplemented with laboratory-reared, translocated individuals. Future research aimed at improving the understanding of the mechanisms of Wolbachia transmission in nature, their impact on the host, and their role in host species formation may shed light on the influence of Wolbachia as an evolutionary driver, especially in Hawaiian ecosystems.

Keywords: co-phylogenetic reconciliation; co-speciation; evolution; horizontal transfer; stochastic character trait mapping; vertical transfer.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Animals
Drosophila / genetics
Ecosystem*
Female
Hawaii
Phylogeny
Wolbachia* / genetics

Grants and funding

This work research was funded by the National Science Foundation (grant No. 1345247) and M.R.B. was partially funded by the U. S. Geological Survey, Pacific Island Ecosystems Research Center.