Wolbachia infection facilitates adaptive increase in male egg size in response to environmental changes

Abstract Under challenging conditions such as maladapted biotic and abiotic conditions, females can plastically adjust their egg size (gamete or zygote size) to counteract fitness declines early in life. Recent evidence suggests that endosymbionts may enhance this egg-size plasticity. Possible endos...

Full description

Saved in:
Bibliographic Details
Main Authors: Eloïse Leroy, Siyi Gao, Maya Gonzalez, Marie-Pierre Ellies-Oury, Midori Tuda
Format: Article
Language:English
Published: Nature Portfolio 2025-04-01
Series:Scientific Reports
Subjects:
Online Access:https://doi.org/10.1038/s41598-025-96680-6
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850181669074501632
author Eloïse Leroy
Siyi Gao
Maya Gonzalez
Marie-Pierre Ellies-Oury
Midori Tuda
author_facet Eloïse Leroy
Siyi Gao
Maya Gonzalez
Marie-Pierre Ellies-Oury
Midori Tuda
author_sort Eloïse Leroy
collection DOAJ
description Abstract Under challenging conditions such as maladapted biotic and abiotic conditions, females can plastically adjust their egg size (gamete or zygote size) to counteract fitness declines early in life. Recent evidence suggests that endosymbionts may enhance this egg-size plasticity. Possible endosymbionts’ modification of impact of multiple stressors is not well explored. Therefore, this study aims to test (1) whether Wolbachia infection influences the plasticity of parental investment in egg size under suboptimal environmental conditions and (2) whether the plasticity depends on the sex of eggs. We used three lines of the azuki bean beetle (Callosobruchus chinensis): a line coinfected with the wBruCon and wBruOri Wolbachia strains, a cured line infected solely with the wBruCon, and an uninfected (cured) line. These lines were subjected to either a control environment or a simulated climate change environment (elevated temperature and carbon dioxide levels, eT&CO2) to examine Wolbachia infection effects on parental investment in their offspring (egg size) and its subsequent impact on offspring fitness, including survival, development, and adult lifespan under starvation. After two days of eT&CO2 exposure, coinfected parents increased male egg size only. Larger eggs developed faster in both sexes and exhibited higher survival. However, offspring adult lifespan was not influenced by egg size but by environment, sex, Wolbachia infection, and development time: eT&CO2 reduced male lifespan but not female lifespan, the singly-infected line females lived longer than coinfected and uninfected line females, and shorter development time linked to longer lifespan. The negative correlation between development time and lifespan was higher under eT&CO2 but not sex-specific. This study is the first to demonstrate sex-specific egg size plasticity associated with Wolbachia infection in species with sex determination systems other than haplodiploid.
format Article
id doaj-art-a97a1e1df4794439a41f1f9b2c4fb7a3
institution OA Journals
issn 2045-2322
language English
publishDate 2025-04-01
publisher Nature Portfolio
record_format Article
series Scientific Reports
spelling doaj-art-a97a1e1df4794439a41f1f9b2c4fb7a32025-08-20T02:17:50ZengNature PortfolioScientific Reports2045-23222025-04-0115111110.1038/s41598-025-96680-6Wolbachia infection facilitates adaptive increase in male egg size in response to environmental changesEloïse Leroy0Siyi Gao1Maya Gonzalez2Marie-Pierre Ellies-Oury3Midori Tuda4Laboratory of Insect Natural Enemies, Faculty of Agriculture, Kyushu UniversityLaboratory of Insect Natural Enemies, Faculty of Agriculture, Kyushu UniversityBordeaux Sciences AgroBordeaux Sciences AgroLaboratory of Insect Natural Enemies, Faculty of Agriculture, Kyushu UniversityAbstract Under challenging conditions such as maladapted biotic and abiotic conditions, females can plastically adjust their egg size (gamete or zygote size) to counteract fitness declines early in life. Recent evidence suggests that endosymbionts may enhance this egg-size plasticity. Possible endosymbionts’ modification of impact of multiple stressors is not well explored. Therefore, this study aims to test (1) whether Wolbachia infection influences the plasticity of parental investment in egg size under suboptimal environmental conditions and (2) whether the plasticity depends on the sex of eggs. We used three lines of the azuki bean beetle (Callosobruchus chinensis): a line coinfected with the wBruCon and wBruOri Wolbachia strains, a cured line infected solely with the wBruCon, and an uninfected (cured) line. These lines were subjected to either a control environment or a simulated climate change environment (elevated temperature and carbon dioxide levels, eT&CO2) to examine Wolbachia infection effects on parental investment in their offspring (egg size) and its subsequent impact on offspring fitness, including survival, development, and adult lifespan under starvation. After two days of eT&CO2 exposure, coinfected parents increased male egg size only. Larger eggs developed faster in both sexes and exhibited higher survival. However, offspring adult lifespan was not influenced by egg size but by environment, sex, Wolbachia infection, and development time: eT&CO2 reduced male lifespan but not female lifespan, the singly-infected line females lived longer than coinfected and uninfected line females, and shorter development time linked to longer lifespan. The negative correlation between development time and lifespan was higher under eT&CO2 but not sex-specific. This study is the first to demonstrate sex-specific egg size plasticity associated with Wolbachia infection in species with sex determination systems other than haplodiploid.https://doi.org/10.1038/s41598-025-96680-6Inclusive fitnessInsectModified atmosphereParent agePlasticityReproduction
spellingShingle Eloïse Leroy
Siyi Gao
Maya Gonzalez
Marie-Pierre Ellies-Oury
Midori Tuda
Wolbachia infection facilitates adaptive increase in male egg size in response to environmental changes
Scientific Reports
Inclusive fitness
Insect
Modified atmosphere
Parent age
Plasticity
Reproduction
title Wolbachia infection facilitates adaptive increase in male egg size in response to environmental changes
title_full Wolbachia infection facilitates adaptive increase in male egg size in response to environmental changes
title_fullStr Wolbachia infection facilitates adaptive increase in male egg size in response to environmental changes
title_full_unstemmed Wolbachia infection facilitates adaptive increase in male egg size in response to environmental changes
title_short Wolbachia infection facilitates adaptive increase in male egg size in response to environmental changes
title_sort wolbachia infection facilitates adaptive increase in male egg size in response to environmental changes
topic Inclusive fitness
Insect
Modified atmosphere
Parent age
Plasticity
Reproduction
url https://doi.org/10.1038/s41598-025-96680-6
work_keys_str_mv AT eloiseleroy wolbachiainfectionfacilitatesadaptiveincreaseinmaleeggsizeinresponsetoenvironmentalchanges
AT siyigao wolbachiainfectionfacilitatesadaptiveincreaseinmaleeggsizeinresponsetoenvironmentalchanges
AT mayagonzalez wolbachiainfectionfacilitatesadaptiveincreaseinmaleeggsizeinresponsetoenvironmentalchanges
AT mariepierreelliesoury wolbachiainfectionfacilitatesadaptiveincreaseinmaleeggsizeinresponsetoenvironmentalchanges
AT midorituda wolbachiainfectionfacilitatesadaptiveincreaseinmaleeggsizeinresponsetoenvironmentalchanges