1
|
Zhang DJ, Sun Y, Yamada H, Wu Y, Wang G, Feng QD, Paerhande D, Maiga H, Bouyer J, Qian J, Wu ZD, Zheng XY. Effects of radiation on the fitness, sterility and arbovirus susceptibility of a Wolbachia-free Aedes albopictus strain for use in the sterile insect technique. PEST MANAGEMENT SCIENCE 2023; 79:4186-4196. [PMID: 37318795 DOI: 10.1002/ps.7615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/06/2023] [Accepted: 06/15/2023] [Indexed: 06/16/2023]
Abstract
BACKGROUND The sterile insect technique (SIT) is a green and species-specific insect pest control technique that suppresses target populations by releasing factory-reared, radiosterilized males into the wild. Once released, it is important to be able to distinguish the released males from the wild males for monitoring purposes. Several methods to mark the sterile males exist. However, most have limitations due to monetary, process efficiency, or insect quality. Aedes albopictus is naturally infected with Wolbachia at a high prevalence, therefore the elimination of Wolbachia can serve as a biomarker to distinguish factory-reared male mosquitoes from wild conspecifics. RESULTS In this study, a Wolbachia-free Ae. albopictus GT strain was developed and its fitness evaluated, which was found to be comparable to the wild GUA strain. In addition, GT male mosquitoes were irradiated at the adult stage and a dose of 20 Gy or more induced over 99% sterility. Moreover, a dose of 30 Gy (almost completely sterilizing male and female mosquitoes) had limited effects on the mating competitiveness of GT males and the vector competence of GT females, respectively. However, radiation reduced mosquito longevity, regardless of sex. CONCLUSION Our results indicate that the Ae. albopictus GT strain can be distinguished from wild mosquitoes based on Wolbachia status and shows similar fitness, radio-sensitivity and arbovirus susceptibility to the GUA strain, indicating that it is feasible to use the GT strain to suppress Ae. albopictus populations for SIT programmes. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Collapse
Affiliation(s)
- Dong-Jing Zhang
- Chinese Atomic Energy Agency Center of Excellence on Nuclear Technology Applications for Insect Control, Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-sen University, Guangzhou, China
- SYSU Nuclear and Insect Biotechnology Co., Ltd, Dongguan, China
- International Atomic Energy Agency Collaborating Centre, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Engineering Technology Research Center for Diseases-Vectors Control, Sun Yat-sen University, Guangzhou, China
- NHC Key Laboratory of Tropical Disease Control, Hainan Medical University, Haikou, China
| | - Yan Sun
- Chinese Atomic Energy Agency Center of Excellence on Nuclear Technology Applications for Insect Control, Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-sen University, Guangzhou, China
- SYSU Nuclear and Insect Biotechnology Co., Ltd, Dongguan, China
- International Atomic Energy Agency Collaborating Centre, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Engineering Technology Research Center for Diseases-Vectors Control, Sun Yat-sen University, Guangzhou, China
| | - Hanano Yamada
- Insect Pest Control Laboratory, Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture, Vienna, Austria
| | - Yu Wu
- Chinese Atomic Energy Agency Center of Excellence on Nuclear Technology Applications for Insect Control, Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-sen University, Guangzhou, China
- International Atomic Energy Agency Collaborating Centre, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Engineering Technology Research Center for Diseases-Vectors Control, Sun Yat-sen University, Guangzhou, China
| | - Gang Wang
- Chinese Atomic Energy Agency Center of Excellence on Nuclear Technology Applications for Insect Control, Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-sen University, Guangzhou, China
- International Atomic Energy Agency Collaborating Centre, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Engineering Technology Research Center for Diseases-Vectors Control, Sun Yat-sen University, Guangzhou, China
| | - Qing-Deng Feng
- Chinese Atomic Energy Agency Center of Excellence on Nuclear Technology Applications for Insect Control, Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-sen University, Guangzhou, China
- International Atomic Energy Agency Collaborating Centre, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Engineering Technology Research Center for Diseases-Vectors Control, Sun Yat-sen University, Guangzhou, China
| | - Dilinuer Paerhande
- Chinese Atomic Energy Agency Center of Excellence on Nuclear Technology Applications for Insect Control, Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-sen University, Guangzhou, China
- International Atomic Energy Agency Collaborating Centre, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Engineering Technology Research Center for Diseases-Vectors Control, Sun Yat-sen University, Guangzhou, China
| | - Hamidou Maiga
- Insect Pest Control Laboratory, Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture, Vienna, Austria
- Institut de Recherche en Sciences de la Santé, Direction Régionale de l'Ouest, Bobo-Dioulasso, Burkina Faso
| | - Jérémy Bouyer
- Insect Pest Control Laboratory, Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture, Vienna, Austria
| | - Jun Qian
- Chinese Atomic Energy Agency Center of Excellence on Nuclear Technology Applications for Insect Control, Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-sen University, Guangzhou, China
| | - Zhong-Dao Wu
- Chinese Atomic Energy Agency Center of Excellence on Nuclear Technology Applications for Insect Control, Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-sen University, Guangzhou, China
- International Atomic Energy Agency Collaborating Centre, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Engineering Technology Research Center for Diseases-Vectors Control, Sun Yat-sen University, Guangzhou, China
| | - Xiao-Ying Zheng
- Chinese Atomic Energy Agency Center of Excellence on Nuclear Technology Applications for Insect Control, Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-sen University, Guangzhou, China
- International Atomic Energy Agency Collaborating Centre, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Engineering Technology Research Center for Diseases-Vectors Control, Sun Yat-sen University, Guangzhou, China
| |
Collapse
|
2
|
Field EN, Smith RC. Seasonality influences key physiological components contributing to Culex pipiens vector competence. FRONTIERS IN INSECT SCIENCE 2023; 3:1144072. [PMID: 38469495 PMCID: PMC10926469 DOI: 10.3389/finsc.2023.1144072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 05/12/2023] [Indexed: 03/13/2024]
Abstract
Mosquitoes are the most important animal vector of disease on the planet, transmitting a variety of pathogens of both medical and veterinary importance. Mosquito-borne diseases display distinct seasonal patterns driven by both environmental and biological variables. However, an important, yet unexplored component of these patterns is the potential for seasonal influences on mosquito physiology that may ultimately influence vector competence. To address this question, we selected Culex pipiens, a primary vector of the West Nile virus (WNV) in the temperate United States, to examine the seasonal impacts on mosquito physiology by examining known immune and bacterial components implicated in mosquito arbovirus infection. Semi-field experiments were performed under spring, summer, and late-summer conditions, corresponding to historically low-, medium-, and high-intensity periods of WNV transmission, respectively. Through these experiments, we observed differences in the expression of immune genes and RNA interference (RNAi) pathway components, as well as changes in the distribution and abundance of Wolbachia in the mosquitoes across seasonal cohorts. Together, these findings support the conclusion that seasonal changes significantly influence mosquito physiology and components of the mosquito microbiome, suggesting that seasonality may impact mosquito susceptibility to pathogen infection, which could account for the temporal patterns in mosquito-borne disease transmission.
Collapse
Affiliation(s)
- Eleanor N Field
- Department of Plant Pathology, Entomology and Microbiology, Iowa State University, Ames, IA, United States
| | - Ryan C Smith
- Department of Plant Pathology, Entomology and Microbiology, Iowa State University, Ames, IA, United States
| |
Collapse
|
3
|
Allman MJ, Lin YH, Joubert DA, Addley-Cook J, Mejía-Torres MC, Simmons CP, Flores HA, Fraser JE. Enhancing the scalability of Wolbachia-based vector-borne disease management: time and temperature limits for storage and transport of Wolbachia-infected Aedes aegypti eggs for field releases. Parasit Vectors 2023; 16:108. [PMID: 36934294 PMCID: PMC10024388 DOI: 10.1186/s13071-023-05724-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 03/02/2023] [Indexed: 03/20/2023] Open
Abstract
BACKGROUND Introgression of the bacterial endosymbiont Wolbachia into Aedes aegypti populations is a biocontrol approach being used to reduce arbovirus transmission. This requires mass release of Wolbachia-infected mosquitoes. While releases have been conducted using a variety of techniques, egg releases, using water-soluble capsules containing mosquito eggs and larval food, offer an attractive method due to its potential to reduce onsite resource requirements. However, optimisation of this approach is required to ensure there is no detrimental impact on mosquito fitness and to promote successful Wolbachia introgression. METHODS We determined the impact of storage time and temperature on wild-type (WT) and Wolbachia-infected (wMel or wAlbB strains) Ae. aegypti eggs. Eggs were stored inside capsules over 8 weeks at 18 °C or 22 °C and hatch rate, emergence rate and Wolbachia density were determined. We next examined egg quality and Wolbachia density after exposing eggs to 4-40 °C to determine how eggs may be impacted if exposed to extreme temperatures during shipment. RESULTS Encapsulating eggs for 8 weeks did not negatively impact egg viability or resulting adult emergence and Wolbachia density compared to controls. When eggs were exposed to temperatures within 4-36 °C for 48 h, their viability and resulting adult Wolbachia density were maintained; however, both were significantly reduced when exposed to 40 °C. CONCLUSIONS We describe the time and temperature limits for maintaining viability of Wolbachia-infected Ae. aegypti eggs when encapsulated or exposed to extreme temperatures. These findings could improve the efficiency of mass releases by providing transport and storage constraints to ensure only high-quality material is utilised during field releases.
Collapse
Affiliation(s)
- Megan J. Allman
- grid.1002.30000 0004 1936 7857Institute of Vector-borne Diseases, Monash University, Melbourne, VIC 3800 Australia
- grid.1002.30000 0004 1936 7857Department of Microbiology, Monash University, Melbourne, VIC 3800 Australia
| | - Ya-Hsun Lin
- grid.1002.30000 0004 1936 7857World Mosquito Program, Monash University, Melbourne, VIC 3800 Australia
| | - D. Albert Joubert
- grid.1002.30000 0004 1936 7857World Mosquito Program, Monash University, Melbourne, VIC 3800 Australia
| | - Jessica Addley-Cook
- grid.1002.30000 0004 1936 7857World Mosquito Program, Monash University, Melbourne, VIC 3800 Australia
| | - Maria Camila Mejía-Torres
- grid.1002.30000 0004 1936 7857World Mosquito Program, Monash University, Melbourne, VIC 3800 Australia
| | - Cameron P. Simmons
- grid.1002.30000 0004 1936 7857Institute of Vector-borne Diseases, Monash University, Melbourne, VIC 3800 Australia
- grid.1002.30000 0004 1936 7857World Mosquito Program, Monash University, Melbourne, VIC 3800 Australia
| | - Heather A. Flores
- grid.1002.30000 0004 1936 7857Institute of Vector-borne Diseases, Monash University, Melbourne, VIC 3800 Australia
- grid.1002.30000 0004 1936 7857School of Biological Sciences, Monash University, Melbourne, VIC 3800 Australia
| | - Johanna E. Fraser
- grid.1002.30000 0004 1936 7857Institute of Vector-borne Diseases, Monash University, Melbourne, VIC 3800 Australia
- grid.1002.30000 0004 1936 7857Department of Microbiology, Monash University, Melbourne, VIC 3800 Australia
| |
Collapse
|
4
|
Alomar AA, Pérez-Ramos DW, Kim D, Kendziorski NL, Eastmond BH, Alto BW, Caragata EP. Native Wolbachia infection and larval competition stress shape fitness and West Nile virus infection in Culex quinquefasciatus mosquitoes. Front Microbiol 2023; 14:1138476. [PMID: 37007535 PMCID: PMC10050331 DOI: 10.3389/fmicb.2023.1138476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 02/23/2023] [Indexed: 03/17/2023] Open
Abstract
IntroductionWolbachia transinfections established in key mosquito vectors, including Aedes aegypti are typically associated with pathogen blocking—reduced susceptibility to infection with key pathogens and reduced likelihood those pathogens are transmitted to new hosts. Host-symbiont-virus interactions are less well understood in mosquitoes like Culex quinquefasciatus, which naturally harbor Wolbachia, with pathogen blocking observed in some populations but not others, potentially due to innate differences in their Wolbachia load. In nature, mosquito larvae are often subject to developmental stresses associated with larval competition, which can lead to reduced body size and differential susceptibility to arbovirus infection.MethodsIn this study, we sought to understand whether competition stress and Wolbachia infection in Cx. quinquefasciatus combine to impact host fitness and susceptibility to infection with West Nile virus. We reared Wolbachia-infected and uninfected Cx. quinquefasciatus larvae under three competition stress levels, increasing larval density without increasing the amount of food supplied. We then monitored larval development and survival, measured wing length and quantified Wolbachia density in adults, and then challenged mosquitoes from each treatment group orally with West Nile virus.Results and DiscussionWe observed that high competition stress extended development time, decreased the likelihood of eclosion, decreased body size, and increased susceptibility to West Nile virus (WNV) infection. We also observed that Wolbachia infection reduced WNV load under low competition stress, and significantly improved the rate of survival for larval reared under higher competition stress. Consequently, our data suggest that native Wolbachia infection in Cx. quinquefasciatus has differential consequences for host fitness and susceptibility to WNV infection depending on competition stress.
Collapse
|
5
|
Zeng Q, She L, Yuan H, Luo Y, Wang R, Mao W, Wang W, She Y, Wang C, Shi M, Cao T, Gan R, Li Y, Zhou J, Qian W, Hu S, Wang Y, Zheng X, Li K, Bai L, Pan X, Xi Z. A standalone incompatible insect technique enables mosquito suppression in the urban subtropics. Commun Biol 2022; 5:1419. [PMID: 36575240 PMCID: PMC9793375 DOI: 10.1038/s42003-022-04332-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 12/01/2022] [Indexed: 12/28/2022] Open
Abstract
The strong suppression of Aedes albopictus on two Guangzhou islands in China has been successfully achieved by releasing males with an artificial triple-Wolbachia infection. However, it requires the use of radiation to sterilize residual females to prevent population replacement. To develop a highly effective tool for dengue control, we tested a standalone incompatible insect technique (IIT) to control A. albopictus in the urban area of Changsha, an inland city where dengue recently emerged. Male mosquitoes were produced in a mass rearing facility in Guangzhou and transported over 670 km under low temperature to the release site. After a once-per-week release with high numbers of males (phase I) and a subsequent twice-per-week release with low numbers of males (phase II), the average numbers of hatched eggs and female adults collected weekly per trap were reduced by 97% and 85%, respectively. The population suppression caused a 94% decrease in mosquito biting at the release site compared to the control site. Remarkably, this strong suppression was achieved using only 28% of the number of males released in a previous trial. Despite the lack of irradiation to sterilize residual females, no triple-infected mosquitoes were detected in the field post release based on the monitoring of adult and larval A. albopictus populations for two years, indicating that population replacement was prevented. Our results support the feasibility of implementing a standalone IIT for dengue control in urban areas.
Collapse
Affiliation(s)
- Qin Zeng
- grid.411427.50000 0001 0089 3695The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, Department of Medical Laboratory Science, Hunan Normal University School of Medicine, Changsha, Hunan PR China ,grid.411427.50000 0001 0089 3695The Key Laboratory of Protein Chemistry and Developmental Biology of Fish of Ministry of Education, Hunan Normal University, Changsha, Hunan PR China
| | - Lingzhi She
- grid.411427.50000 0001 0089 3695The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, Department of Medical Laboratory Science, Hunan Normal University School of Medicine, Changsha, Hunan PR China ,grid.411427.50000 0001 0089 3695The Key Laboratory of Protein Chemistry and Developmental Biology of Fish of Ministry of Education, Hunan Normal University, Changsha, Hunan PR China
| | - Hao Yuan
- grid.411427.50000 0001 0089 3695The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, Department of Medical Laboratory Science, Hunan Normal University School of Medicine, Changsha, Hunan PR China ,grid.411427.50000 0001 0089 3695The Key Laboratory of Protein Chemistry and Developmental Biology of Fish of Ministry of Education, Hunan Normal University, Changsha, Hunan PR China
| | - Yuying Luo
- grid.411427.50000 0001 0089 3695The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, Department of Medical Laboratory Science, Hunan Normal University School of Medicine, Changsha, Hunan PR China ,grid.411427.50000 0001 0089 3695The Key Laboratory of Protein Chemistry and Developmental Biology of Fish of Ministry of Education, Hunan Normal University, Changsha, Hunan PR China
| | - Renke Wang
- grid.411427.50000 0001 0089 3695The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, Department of Medical Laboratory Science, Hunan Normal University School of Medicine, Changsha, Hunan PR China ,grid.411427.50000 0001 0089 3695The Key Laboratory of Protein Chemistry and Developmental Biology of Fish of Ministry of Education, Hunan Normal University, Changsha, Hunan PR China
| | - Wei Mao
- grid.411427.50000 0001 0089 3695The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, Department of Medical Laboratory Science, Hunan Normal University School of Medicine, Changsha, Hunan PR China ,grid.411427.50000 0001 0089 3695The Key Laboratory of Protein Chemistry and Developmental Biology of Fish of Ministry of Education, Hunan Normal University, Changsha, Hunan PR China
| | - Weifeng Wang
- grid.411427.50000 0001 0089 3695The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, Department of Medical Laboratory Science, Hunan Normal University School of Medicine, Changsha, Hunan PR China ,grid.411427.50000 0001 0089 3695The Key Laboratory of Protein Chemistry and Developmental Biology of Fish of Ministry of Education, Hunan Normal University, Changsha, Hunan PR China
| | - Yueting She
- grid.411427.50000 0001 0089 3695The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, Department of Medical Laboratory Science, Hunan Normal University School of Medicine, Changsha, Hunan PR China ,grid.411427.50000 0001 0089 3695The Key Laboratory of Protein Chemistry and Developmental Biology of Fish of Ministry of Education, Hunan Normal University, Changsha, Hunan PR China
| | - Chaojun Wang
- grid.411427.50000 0001 0089 3695The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, Department of Medical Laboratory Science, Hunan Normal University School of Medicine, Changsha, Hunan PR China ,grid.411427.50000 0001 0089 3695The Key Laboratory of Protein Chemistry and Developmental Biology of Fish of Ministry of Education, Hunan Normal University, Changsha, Hunan PR China
| | - Mengyi Shi
- grid.411427.50000 0001 0089 3695The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, Department of Medical Laboratory Science, Hunan Normal University School of Medicine, Changsha, Hunan PR China ,grid.411427.50000 0001 0089 3695The Key Laboratory of Protein Chemistry and Developmental Biology of Fish of Ministry of Education, Hunan Normal University, Changsha, Hunan PR China
| | - Ting Cao
- grid.411427.50000 0001 0089 3695The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, Department of Medical Laboratory Science, Hunan Normal University School of Medicine, Changsha, Hunan PR China ,grid.411427.50000 0001 0089 3695The Key Laboratory of Protein Chemistry and Developmental Biology of Fish of Ministry of Education, Hunan Normal University, Changsha, Hunan PR China
| | - Renxian Gan
- Guangzhou Wolbaki Biotech Co., Ltd, Guangzhou, Guangdong PR China
| | - Yongjun Li
- Guangzhou Wolbaki Biotech Co., Ltd, Guangzhou, Guangdong PR China ,grid.258164.c0000 0004 1790 3548Present Address: Department of Pathogen Biology, School of Medicine, Jinan University, Guangzhou, PR China
| | - Jiayi Zhou
- Guangzhou Wolbaki Biotech Co., Ltd, Guangzhou, Guangdong PR China
| | - Wei Qian
- Guangzhou Wolbaki Biotech Co., Ltd, Guangzhou, Guangdong PR China
| | - Shixiong Hu
- grid.508374.dHunan Provincial Center for Disease Control and Prevention, Changsha, Hunan PR China
| | - Yong Wang
- grid.216417.70000 0001 0379 7164Department of Forensic Science, School of Basic Medical Science, Central South University, Changsha, Hunan PR China
| | - Xiaoying Zheng
- grid.12981.330000 0001 2360 039XSun Yat-sen University—Michigan State University Joint Center of Vector Control for Tropical Diseases, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong PR China
| | - Kuibiao Li
- grid.508371.80000 0004 1774 3337Guangzhou Center for Disease Control and Prevention, Guangzhou, Guangdong PR China
| | - Lianyang Bai
- grid.410598.10000 0004 4911 9766Hunan Academy of Agricultural Sciences, Changsha, Hunan PR China
| | - Xiaoling Pan
- grid.411427.50000 0001 0089 3695The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, Department of Medical Laboratory Science, Hunan Normal University School of Medicine, Changsha, Hunan PR China ,grid.411427.50000 0001 0089 3695The Key Laboratory of Protein Chemistry and Developmental Biology of Fish of Ministry of Education, Hunan Normal University, Changsha, Hunan PR China
| | - Zhiyong Xi
- Guangzhou Wolbaki Biotech Co., Ltd, Guangzhou, Guangdong PR China ,grid.17088.360000 0001 2150 1785Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI USA
| |
Collapse
|
6
|
Zhang H, Gao J, Ma Z, Liu Y, Wang G, Liu Q, Du Y, Xing D, Li C, Zhao T, Jiang Y, Dong Y, Guo X, Zhao T. Wolbachia infection in field-collected Aedes aegypti in Yunnan Province, southwestern China. Front Cell Infect Microbiol 2022; 12:1082809. [PMID: 36530420 PMCID: PMC9748079 DOI: 10.3389/fcimb.2022.1082809] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 11/10/2022] [Indexed: 12/02/2022] Open
Abstract
Background Wolbachia is gram-negative and common intracellular bacteria, which is maternally inherited endosymbionts and could expand their propagation in host populations by means of various manipulations. Recent reports reveal the natural infection of Wolbachia in Aedes Aegypti in Malaysia, India, Philippines, Thailand and the United States. At present, none of Wolbachia natural infection in Ae. aegypti has been reported in China. Methods A total of 480 Ae. aegypti adult mosquitoes were collected from October and November 2018 based on the results of previous investigations and the distribution of Ae. aegypti in Yunnan. Each individual sample was processed and screened for the presence of Wolbachia by PCR with wsp primers. Phylogenetic trees for the wsp gene was constructed using the neighbour-joining method with 1,000 bootstrap replicates, and the p-distance distribution model of molecular evolution was applied. Results 24 individual adult mosquito samples and 10 sample sites were positive for Wolbachia infection. The Wolbachia infection rate (IR) of each population ranged from 0 - 41.7%. The infection rate of group A alone was 0%-10%, the infection rate of group B alone was 0%-7.7%, and the infection rate of co-infection with A and B was 0-33.3%. Conclusions Wolbachia infection in wild Ae. aegypti in China is the first report based on PCR amplification of the Wolbachia wsp gene. The Wolbachia infection is 5%, and the wAlbA and wAlbB strains were found to be prevalent in the natural population of Ae. aegypti in Yunnan Province.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - XiaoXia Guo
- *Correspondence: XiaoXia Guo, ; TongYan Zhao,
| | | |
Collapse
|
7
|
Wolbachia inhibits ovarian formation and increases blood feeding rate in female Aedes aegypti. PLoS Negl Trop Dis 2022; 16:e0010913. [DOI: 10.1371/journal.pntd.0010913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 11/23/2022] [Accepted: 10/28/2022] [Indexed: 11/13/2022] Open
Abstract
Wolbachia, a gram-negative endosymbiotic bacterium widespread in arthropods, is well-known for changing the reproduction of its host in ways that increase its rate of spread, but there are also costs to hosts that can reduce this. Here we investigated a novel reproductive alteration of Wolbachia wAlbB on its host Aedes aegypti, using studies on mosquito life history traits, ovarian dissection, as well as gene expression assays. We found that an extended period of the larval stage as well as the egg stage (as previously shown) can increase the proportion of Wolbachia-infected females that become infertile; an effect which was not observed in uninfected females. Infertile females had incomplete ovarian formation and also showed a higher frequency of blood feeding following a prior blood meal, indicating that they do not enter a complete gonotrophic cycle. Treatments leading to infertility also decreased the expression of genes related to reproduction, especially the vitellogenin receptor gene whose product regulates the uptake of vitellogenin (Vg) into ovaries. Our results demonstrate effects associated with the development of infertility in wAlbB-infected Ae. aegypti females with implications for Wolbachia releases. The results also have implications for the evolution of Wolbachia infections in novel hosts.
Collapse
|
8
|
Gu X, Ross PA, Rodriguez-Andres J, Robinson KL, Yang Q, Lau MJ, Hoffmann AA. A wMel Wolbachia variant in Aedes aegypti from field-collected Drosophila melanogaster with increased phenotypic stability under heat stress. Environ Microbiol 2022; 24:2119-2135. [PMID: 35319146 PMCID: PMC9544352 DOI: 10.1111/1462-2920.15966] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 02/15/2022] [Accepted: 03/02/2022] [Indexed: 02/03/2023]
Abstract
Mosquito‐borne diseases remain a major cause of morbidity and mortality. Population replacement strategies involving the wMel strain of Wolbachia are being used widely to control mosquito‐borne diseases. However, these strategies may be influenced by temperature because wMel is vulnerable to heat. wMel infections in Drosophila melanogaster are genetically diverse, but few transinfections of wMel variants have been generated in Aedes aegypti. Here, we successfully transferred a wMel variant (termed wMelM) originating from a field‐collected D. melanogaster into Ae. aegypti. The new wMelM variant (clade I) is genetically distinct from the original wMel transinfection (clade III), and there are no genomic differences between wMelM in its original and transinfected host. We compared wMelM with wMel in its effects on host fitness, temperature tolerance, Wolbachia density, vector competence, cytoplasmic incompatibility and maternal transmission under heat stress in a controlled background. wMelM showed a higher heat tolerance than wMel, likely due to higher overall densities within the mosquito. Both wMel variants had minimal host fitness costs, complete cytoplasmic incompatibility and maternal transmission, and dengue virus blocking under laboratory conditions. Our results highlight phenotypic differences between Wolbachia variants and wMelM shows potential as an alternative strain in areas with strong seasonal temperature fluctuations.
Collapse
Affiliation(s)
- Xinyue Gu
- Pest and Environmental Adaptation Research Group, Bio21 Institute and the School of BioSciences, The University of Melbourne, Parkville, Vic, Australia
| | - Perran A Ross
- Pest and Environmental Adaptation Research Group, Bio21 Institute and the School of BioSciences, The University of Melbourne, Parkville, Vic, Australia
| | - Julio Rodriguez-Andres
- Peter Doherty Institute for Infection and Immunity and Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Melbourne, Vic, 3000, Australia
| | - Katie L Robinson
- Pest and Environmental Adaptation Research Group, Bio21 Institute and the School of BioSciences, The University of Melbourne, Parkville, Vic, Australia
| | - Qiong Yang
- Pest and Environmental Adaptation Research Group, Bio21 Institute and the School of BioSciences, The University of Melbourne, Parkville, Vic, Australia
| | - Meng-Jia Lau
- Pest and Environmental Adaptation Research Group, Bio21 Institute and the School of BioSciences, The University of Melbourne, Parkville, Vic, Australia
| | - Ary A Hoffmann
- Pest and Environmental Adaptation Research Group, Bio21 Institute and the School of BioSciences, The University of Melbourne, Parkville, Vic, Australia
| |
Collapse
|
9
|
Konorov EA, Lukashev AN, Oyun NY. Genome Variation of Endosymbiotic Wolbachia in Introduced Populations of Asian Tiger Mosquito Aedes albopictus from Krasnodar Krai. RUSS J GENET+ 2022. [DOI: 10.1134/s1022795422020065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
10
|
Temperature effects on cellular host-microbe interactions explain continent-wide endosymbiont prevalence. Curr Biol 2022; 32:878-888.e8. [PMID: 34919808 PMCID: PMC8891084 DOI: 10.1016/j.cub.2021.11.065] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 11/09/2021] [Accepted: 11/26/2021] [Indexed: 01/03/2023]
Abstract
Endosymbioses influence host physiology, reproduction, and fitness, but these relationships require efficient microbe transmission between host generations to persist. Maternally transmitted Wolbachia are the most common known endosymbionts,1 but their frequencies vary widely within and among host populations for unknown reasons.2,3 Here, we integrate genomic, cellular, and phenotypic analyses with mathematical models to provide an unexpectedly simple explanation for global wMel Wolbachia prevalence in Drosophila melanogaster. Cooling temperatures decrease wMel cellular abundance at a key stage of host oogenesis, producing temperature-dependent variation in maternal transmission that plausibly explains latitudinal clines of wMel frequencies on multiple continents. wMel sampled from a temperate climate targets the germline more efficiently in the cold than a recently differentiated tropical variant (∼2,200 years ago), indicative of rapid wMel adaptation to climate. Genomic analyses identify a very narrow list of wMel alleles-most notably, a derived stop codon in the major Wolbachia surface protein WspB-that underlie thermal sensitivity of cellular Wolbachia abundance and covary with temperature globally. Decoupling temperate wMel and host genomes further reduces transmission in the cold, a pattern that is characteristic of host-microbe co-adaptation to a temperate climate. Complex interactions among Wolbachia, hosts, and the environment (GxGxE) mediate wMel cellular abundance and maternal transmission, implicating temperature as a key determinant of Wolbachia spread and equilibrium frequencies, in conjunction with Wolbachia effects on host fitness and reproduction.4,5 Our results motivate the strategic use of locally selected wMel variants for Wolbachia-based biocontrol efforts, which protect millions of individuals from arboviruses that cause human disease.6.
Collapse
|
11
|
Yang Y, He Y, Zhu G, Zhang J, Gong Z, Huang S, Lu G, Peng Y, Meng Y, Hao X, Wang C, Sun J, Shang S. Prevalence and molecular characterization of Wolbachia in field-collected Aedes albopictus, Anopheles sinensis, Armigeres subalbatus, Culex pipiens and Cx. tritaeniorhynchus in China. PLoS Negl Trop Dis 2021; 15:e0009911. [PMID: 34710095 PMCID: PMC8577788 DOI: 10.1371/journal.pntd.0009911] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 11/09/2021] [Accepted: 10/15/2021] [Indexed: 01/24/2023] Open
Abstract
Wolbachia are maternally transmitted intracellular bacteria that can naturally and artificially infect arthropods and nematodes. Recently, they were applied to control the spread of mosquito-borne pathogens by causing cytoplasmic incompatibility (CI) between germ cells of females and males. The ability of Wolbachia to induce CI is based on the prevalence and polymorphism of Wolbachia in natural populations of mosquitoes. In this study, we screened the natural infection level and diversity of Wolbachia in field-collected mosquitoes from 25 provinces of China based on partial sequence of Wolbachia surface protein (wsp) gene and multilocus sequence typing (MLST). Among the samples, 2489 mosquitoes were captured from 24 provinces between July and September, 2014 and the remaining 1025 mosquitoes were collected month-by-month in Yangzhou, Jiangsu province between September 2013 and August 2014. Our results showed that the presence of Wolbachia was observed in mosquitoes of Aedes albopictus (97.1%, 331/341), Armigeres subalbatus (95.8%, 481/502), Culex pipiens (87.0%, 1525/1752), Cx. tritaeniorhynchus (17.1%, 14/82), but not Anopheles sinensis (n = 88). Phylogenetic analysis indicated that high polymorphism of wsp and MLST loci was observed in Ae. albopictus mosquitoes, while no or low polymorphisms were in Ar. subalbatus and Cx. pipiens mosquitoes. A total of 12 unique mutations of deduced amino acid were identified in the wsp sequences obtained in this study, including four mutations in Wolbachia supergroup A and eight mutations in supergroup B. This study revealed the prevalence and polymorphism of Wolbachia in mosquitoes in large-scale regions of China and will provide some useful information when performing Wolbachia-based mosquito biocontrol strategies in China. The mosquitoes Aedes albopictus, Anopheles sinensis, Armigeres subalbatus, Culex pipiens and Cx. tritaeniorhynchus are native to China and the major vectors in the transmission of arboviruses, protozoans and nematodes. Recently, an innovative biocontrol strategy has been developed and evaluated based on the ability of Wolbachia to induce cytoplasmic incompatibility (CI), as well as interfere with the infection and replication of pathogens. Since the ability to induce CI largely depends on the density and diversity of Wolbachia, we investigated and characterized the natural infection of Wolbachia in above-mentioned five species of field-collected mosquitoes in 25 provinces of China. The results showed that the positive rates of Wolbachia infection were high in mosquitoes of Ae. albopictus, Ar. subalbatus and Cx. pipiens in large-scale regions of China and low in Cx. tritaeniorhynchus in Guizhou province. Phylogenetic analysis based on Wolbachia surface protein (wsp) gene and five multilocus sequence typing (MLST) loci indicated the high polymorphism of Wolbachia in Ae. albopictus, and low polymorphisms in Ar. subalbatus and Cx. pipiens. This finding contributes to the understanding of the nationwide distribution of Wolbachia and the potential application of this biocontrol strategy in China.
Collapse
Affiliation(s)
- Yi Yang
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses; College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- International Corporation Laboratory of Agriculture and Agricultural Products Safety, Yangzhou University, Yangzhou, China
- * E-mail: (YY); (JS); (SS)
| | - Yifan He
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses; College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Guoding Zhu
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, China
| | - Jilei Zhang
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Zaicheng Gong
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses; College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Siyang Huang
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses; College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- International Corporation Laboratory of Agriculture and Agricultural Products Safety, Yangzhou University, Yangzhou, China
| | - Guangwu Lu
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses; College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Yalan Peng
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses; College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Yining Meng
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses; College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Xiaoli Hao
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses; College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Chengming Wang
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, Alabama, United States of America
| | - Jie Sun
- Shenzhen Academy of Inspection and Quarantine Sciences, Shenzhen, China
- * E-mail: (YY); (JS); (SS)
| | - Shaobin Shang
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses; College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- International Corporation Laboratory of Agriculture and Agricultural Products Safety, Yangzhou University, Yangzhou, China
- * E-mail: (YY); (JS); (SS)
| |
Collapse
|
12
|
Chrostek E, Martins N, Marialva MS, Teixeira L. Wolbachia-Conferred Antiviral Protection Is Determined by Developmental Temperature. mBio 2021; 12:e0292320. [PMID: 34488458 PMCID: PMC8546536 DOI: 10.1128/mbio.02923-20] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 08/11/2021] [Indexed: 12/11/2022] Open
Abstract
Wolbachia is a maternally transmitted bacterium that is widespread in arthropods and filarial nematodes and confers strong antiviral protection in Drosophila melanogaster and other arthropods. Wolbachia-transinfected Aedes aegypti mosquitoes are currently being deployed to fight transmission of dengue and Zika viruses. However, the mechanism of antiviral protection and the factors influencing are still not fully understood. Here, we show that temperature modulates Wolbachia-conferred protection in Drosophila melanogaster. Temperature after infection directly impacts Drosophila C virus (DCV) replication and modulates Wolbachia protection. At higher temperatures, viruses proliferate more and are more lethal, while Wolbachia confers lower protection. Strikingly, host developmental temperature is a determinant of Wolbachia-conferred antiviral protection. While there is strong protection when flies develop from egg to adult at 25°C, the protection is highly reduced or abolished when flies develop at 18°C. However, Wolbachia-induced changes during development are not sufficient to limit virus-induced mortality, as Wolbachia is still required to be present in adults at the time of infection. This developmental effect is general, since it was present in different host genotypes, Wolbachia variants, and upon infection with different viruses. Overall, we show that Wolbachia-conferred antiviral protection is temperature dependent, being present or absent depending on the environmental conditions. This interaction likely impacts Wolbachia-host interactions in nature and, as a result, frequencies of host and symbionts in different climates. Dependence of Wolbachia-mediated pathogen blocking on developmental temperature could be used to dissect the mechanistic bases of protection and influence the deployment of Wolbachia to prevent transmission of arboviruses. IMPORTANCE Insects are often infected with beneficial intracellular bacteria. The bacterium Wolbachia is extremely common in insects and can protect them from pathogenic viruses. This effect is being used to prevent transmission of dengue and Zika viruses by Wolbachia-infected mosquitoes. To understand the biology of insects in the wild, we need to discover which factors affect Wolbachia-conferred antiviral protection. Here, we show that the temperature at which insects develop from eggs to adults can determine the presence or absence of antiviral protection. The environment, therefore, strongly influences this insect-bacterium interaction. Our work may help to provide insights into the mechanism of viral blocking by Wolbachia, deepen our understanding of the geographical distribution of host and symbiont, and incentivize further research on the temperature dependence of Wolbachia-conferred protection for control of mosquito-borne disease.
Collapse
Affiliation(s)
- Ewa Chrostek
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
- Department of Evolution, Ecology and Behaviour, University of Liverpool, United Kingdom
| | - Nelson Martins
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
- Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg, Strasbourg, France
| | - Marta S. Marialva
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
- Department for Biomedical Research, University of Bern, Switzerland
| | - Luís Teixeira
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
- Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
| |
Collapse
|
13
|
Ross PA. Designing effective Wolbachia release programs for mosquito and arbovirus control. Acta Trop 2021; 222:106045. [PMID: 34273308 DOI: 10.1016/j.actatropica.2021.106045] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 07/04/2021] [Accepted: 07/06/2021] [Indexed: 01/22/2023]
Abstract
Mosquitoes carrying endosymbiotic bacteria called Wolbachia are being released in mosquito and arbovirus control programs around the world through two main approaches: population suppression and population replacement. Open field releases of Wolbachia-infected male mosquitoes have achieved over 95% population suppression by reducing the fertility of wild mosquito populations. The replacement of populations with Wolbachia-infected females is self-sustaining and can greatly reduce local dengue transmission by reducing the vector competence of mosquito populations. Despite many successful interventions, significant questions and challenges lie ahead. Wolbachia, viruses and their mosquito hosts can evolve, leading to uncertainty around the long-term effectiveness of a given Wolbachia strain, while few ecological impacts of Wolbachia releases have been explored. Wolbachia strains are diverse and the choice of strain to release should be made carefully, taking environmental conditions and the release objective into account. Mosquito quality control, thoughtful community awareness programs and long-term monitoring of populations are essential for all types of Wolbachia intervention. Releases of Wolbachia-infected mosquitoes show great promise, but existing control measures remain an important way to reduce the burden of mosquito-borne disease.
Collapse
|
14
|
Caragata EP, Dutra HLC, Sucupira PHF, Ferreira AGA, Moreira LA. Wolbachia as translational science: controlling mosquito-borne pathogens. Trends Parasitol 2021; 37:1050-1067. [PMID: 34303627 DOI: 10.1016/j.pt.2021.06.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 06/21/2021] [Accepted: 06/29/2021] [Indexed: 01/23/2023]
Abstract
In this review we examine how exploiting the Wolbachia-mosquito relationship has become an increasingly popular strategy for controlling arbovirus transmission. Field deployments of Wolbachia-infected mosquitoes have led to significant decreases in dengue virus incidence via high levels of mosquito population suppression and replacement, emphasizing the success of Wolbachia approaches. Here, we examine how improved knowledge of Wolbachia-host interactions has provided key insight into the mechanisms of the essential phenotypes of pathogen blocking and cytoplasmic incompatibility. And we discuss recent studies demonstrating that extrinsic factors, such as ambient temperature, can modulate Wolbachia density and maternal transmission. Finally, we assess the prospects of using Wolbachia to control other vectors and agricultural pest species.
Collapse
Affiliation(s)
- Eric P Caragata
- Florida Medical Entomology Laboratory, Department of Entomology and Nematology, Institute of Food and Agricultural Sciences, University of Florida, Vero Beach, FL, USA.
| | - Heverton L C Dutra
- Department of Biology, Pennsylvania State University, University Park, PA, USA
| | - Pedro H F Sucupira
- Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou - Fiocruz, Belo Horizonte, MG, Brazil
| | - Alvaro G A Ferreira
- Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou - Fiocruz, Belo Horizonte, MG, Brazil
| | - Luciano A Moreira
- Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou - Fiocruz, Belo Horizonte, MG, Brazil.
| |
Collapse
|
15
|
Lau MJ, Ross PA, Hoffmann AA. Infertility and fecundity loss of Wolbachia-infected Aedes aegypti hatched from quiescent eggs is expected to alter invasion dynamics. PLoS Negl Trop Dis 2021; 15:e0009179. [PMID: 33591971 PMCID: PMC7909672 DOI: 10.1371/journal.pntd.0009179] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 02/26/2021] [Accepted: 01/26/2021] [Indexed: 02/02/2023] Open
Abstract
The endosymbiotic bacterium Wolbachia shows viral blocking in its mosquito host, leading to its use in arboviral disease control. Releases with Wolbachia strains wMel and wAlbB infecting Aedes aegypti have taken place in several countries. Mosquito egg survival is a key factor influencing population persistence and this trait is also important when eggs are stored prior to releases. We therefore tested the viability of mosquitoes derived from Wolbachia wMel and wAlbB-infected as well as uninfected eggs after long-term storage under diurnal temperature cycles of 11-19°C and 22-30°C. Eggs stored at 11-19°C had higher hatch proportions than those stored at 22-30°C. Adult Wolbachia density declined when they emerged from eggs stored for longer, which was associated with incomplete cytoplasmic incompatibility (CI) when wMel-infected males were crossed with uninfected females. Females from stored eggs at both temperatures continued to show perfect maternal transmission of Wolbachia, but storage reduced the fecundity of both wMel and wAlbB-infected females relative to uninfected mosquitoes. Furthermore, we found a very strong negative impact of the wAlbB infection on the fertility of females stored at 22-30°C, with almost 80% of females hatching after 11 weeks of storage being infertile. Our findings provide guidance for storing Wolbachia-infected A. aegypti eggs to ensure high fitness adult mosquitoes for release. Importantly, they also highlight the likely impact of egg quiescence on the population dynamics of Wolbachia-infected populations in the field, and the potential for Wolbachia to suppress mosquito populations through cumulative fitness costs across warm and dry periods, with expected effects on dengue transmission.
Collapse
Affiliation(s)
- Meng-Jia Lau
- Pest and Environmental Adaptation Research Group, Bio21 Institute and the School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Perran A. Ross
- Pest and Environmental Adaptation Research Group, Bio21 Institute and the School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Ary A. Hoffmann
- Pest and Environmental Adaptation Research Group, Bio21 Institute and the School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
| |
Collapse
|
16
|
Hague MTJ, Caldwell CN, Cooper BS. Pervasive Effects of Wolbachia on Host Temperature Preference. mBio 2020; 11:e01768-20. [PMID: 33024036 PMCID: PMC7542361 DOI: 10.1128/mbio.01768-20] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 08/31/2020] [Indexed: 02/06/2023] Open
Abstract
Heritable symbionts can modify a range of ecologically important host traits, including behavior. About half of all insect species are infected with maternally transmitted Wolbachia, a bacterial endosymbiont known to alter host reproduction, nutrient acquisition, and virus susceptibility. Here, we broadly test the hypothesis that Wolbachia modifies host behavior by assessing the effects of eight different Wolbachia strains on the temperature preference of six Drosophila melanogaster subgroup species. Four of the seven host genotypes infected with A-group Wolbachia strains (wRi in Drosophila simulans, wHa in D. simulans, wSh in Drosophila sechellia, and wTei in Drosophila teissieri) prefer significantly cooler temperatures relative to uninfected genotypes. Contrastingly, when infected with divergent B-group wMau, Drosophila mauritiana prefers a warmer temperature. For most strains, changes to host temperature preference do not alter Wolbachia titer. However, males infected with wSh and wTei tend to experience an increase in titer when shifted to a cooler temperature for 24 h, suggesting that Wolbachia-induced changes to host behavior may promote bacterial replication. Our results indicate that Wolbachia modifications to host temperature preference are likely widespread, which has important implications for insect thermoregulation and physiology. Understanding the fitness consequences of these Wolbachia effects is crucial for predicting evolutionary outcomes of host-symbiont interactions, including how Wolbachia spreads to become common.IMPORTANCE Microbes infect a diversity of species, influencing the performance and fitness of their hosts. Maternally transmitted Wolbachia bacteria infect most insects and other arthropods, making these bacteria some of the most common endosymbionts in nature. Despite their global prevalence, it remains mostly unknown how Wolbachia influence host physiology and behavior to proliferate. We demonstrate pervasive effects of Wolbachia on Drosophila temperature preference. Most hosts infected with A-group Wolbachia prefer cooler temperatures, whereas the one host species infected with divergent B-group Wolbachia prefers warmer temperatures, relative to uninfected genotypes. Changes to host temperature preference generally do not alter Wolbachia abundance in host tissues, but for some A-group strains, adult males have increased Wolbachia titer when shifted to a cooler temperature. This suggests that Wolbachia-induced changes to host behavior may promote bacterial replication. Our results help elucidate the impact of endosymbionts on their hosts amid the global Wolbachia pandemic.
Collapse
Affiliation(s)
- Michael T J Hague
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Chelsey N Caldwell
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Brandon S Cooper
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| |
Collapse
|