Wolbachia Infections in Aedes aegypti Differ Markedly in Their Response to Cyclical Heat Stress

Perran A. Ross; Itsanun Wiwatanaratanabutr; Jason K. Axford; Vanessa L. White; Nancy M. Endersby-Harshman; Ary A. Hoffmann

doi:10.1371/journal.ppat.1006006

Continued Susceptibility of the wMel Wolbachia Infection in Aedes aegypti to Heat Stress Following Field Deployment and Selection

Insects ◽

10.3390/insects9030078 ◽

2018 ◽

Vol 9 (3) ◽

pp. 78 ◽

Cited By ~ 7

Author(s):

Perran Ross ◽

Ary Hoffmann

Keyword(s):

Heat Stress ◽

Aedes Aegypti ◽

High Temperatures ◽

Wolbachia Infection ◽

Field Exposure ◽

Breeding Sites ◽

Laboratory Selection ◽

Mosquito Breeding ◽

Field Deployment ◽

Cyclical Heat

Aedes aegypti mosquitoes infected with the wMel strain of Wolbachia are being deployed to control the spread of arboviruses around the world through blockage of viral transmission. Blockage by Wolbachia in some scenarios may be affected by the susceptibility of wMel to cyclical heat stress during mosquito larval development. We therefore evaluated the potential to generate a heat-resistant strain of wMel in Ae. aegypti through artificial laboratory selection and through exposure to field temperatures across multiple generations. To generate an artificially selected strain, wMel-infected females reared under cyclical heat stress were crossed to wMel-infected males reared at 26 °C. The low proportion of larvae that hatched founded the next generation, and this process was repeated for eight generations. The wMel heat-selected strain (wMel-HS) was similar to wMel (unselected) in its ability to induce cytoplasmic incompatibility and restore compatibility when larvae were reared under cyclical heat stress, but wMel-HS adults exhibited reduced Wolbachia densities at 26 °C. To investigate the effects of field exposure, we compared the response of wMel-infected Ae. aegypti collected from Cairns, Australia where the infection has been established for seven years, to a wMel-infected population maintained in the laboratory for approximately 60 generations. Field and laboratory strains of wMel did not differ in their response to cyclical heat stress or in their phenotypic effects at 26 °C. The capacity for the wMel infection in Ae. aegypti to adapt to high temperatures therefore appears limited, and alternative strains may need to be considered for deployment in environments where high temperatures are regularly experienced in mosquito breeding sites.

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A wMel Wolbachia variant in Aedes aegypti from field-collected Drosophila melanogaster with increased phenotypic stability under heat stress

10.1101/2022.01.02.474744 ◽

2022 ◽

Author(s):

Xinyue Gu ◽

Perran A Ross ◽

Julio Rodriguez-Andres ◽

Katie L. Robinson ◽

Qiong Yang ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Heat Stress ◽

Aedes Aegypti ◽

Cytoplasmic Incompatibility ◽

Vector Competence ◽

Temperature Tolerance ◽

Seasonal Temperature ◽

Maternal Transmission ◽

Tropical Regions ◽

Host Fitness

Mosquito-borne diseases such as dengue, Zika and chikungunya remain a major cause of morbidity and mortality across tropical regions. Population replacement strategies involving the wMel strain of Wolbachia are being used widely to control mosquito-borne diseases transmitted by Aedes aegypti. However, these strategies may be influenced by environmental temperature because wMel is vulnerable to heat stress. wMel infections in their native host Drosophila melanogaster are genetically diverse, but few transinfections of wMel variants have been generated in Ae. aegypti mosquitoes. Here we successfully transferred a wMel variant (termed wMelM) originating from a field-collected D. melanogaster population from Victoria, Australia into Ae. aegypti. The new wMelM variant (clade I) is genetically distinct from the original wMel transinfection (clade III) generated over ten years ago, 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, with stronger cytoplasmic incompatibility and maternal transmission when eggs were exposed to heat stress, 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 standard laboratory conditions. Our results highlight phenotypic differences between closely related Wolbachia variants. wMelM shows potential as an alternative strain to wMel in dengue control programs in areas with strong seasonal temperature fluctuations.

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Effect of age and cyclical heat stress on the serum biochemical profile of broiler chickens

Semina Ciências Agrárias ◽

10.5433/1679-0359.2017v38n3p1383 ◽

2017 ◽

Vol 38 (3) ◽

pp. 1383 ◽

Cited By ~ 5

Author(s):

João Paulo Rodrigues Bueno ◽

Mara Regina Bueno de Mattos Nascimento ◽

Julyana Machado da Silva Martins ◽

Cristiane Ferreira Prazeres Marchini ◽

Luciana Ruggeri Menezes Gotardo ◽

...

Keyword(s):

Uric Acid ◽

Heat Stress ◽

Total Protein ◽

Aspartate Aminotransferase ◽

Broiler Chickens ◽

Low Density Lipoproteins ◽

Control Treatment ◽

Low Density ◽

Very Low Density Lipoproteins ◽

Cyclical Heat

This study aimed to evaluate the influence of age and cyclical heat stress for 1 hour per day on the levels of serum proteins, metabolites, and enzymes in broiler chickens of 21-42 days of age. We used 420 male broiler chickens, Cobb Avian48TM breed, in a completely randomized experimental design, composed of two treatments and six replicates. The treatments consisted of two thermal environments: one in which broiler chickens were raised under natural conditions of temperature and humidity for the first 42 days of age (control) and another in which chickens were subjected to heat stress at 36°C, from days 16 to 42, for 1 hour per day (1200-1300 hours). At 21, 28, 35, and 42 days of age, approximately 5 mL of blood was collected by cardiac puncture in two birds per replicate. In each serum sample, levels of total protein, albumin, globulin, albumin:globulin ratio, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma-glutamyltransferase (GGT) activity and uric acid, creatinine, total cholesterol, triglycerides, high-density lipoproteins (HDL), very low density lipoproteins (VLDL), low-density lipoproteins (LDL), and glucose levels were determined. Concerning the environment and the age, no significant differences in the levels of glucose, uric acid, ALT, triglycerides, and very low density lipoproteins were observed. There was a significant interaction between the environment and the age for cholesterol and LDL values. At 21 days of age, cholesterol and LDL-cholesterol (LDL-C) were higher in birds under stress than in the control treatment birds, which did not occur in other age groups. Aspartate aminotransferase activity was higher in chickens under cyclical heat stress than in chickens subjected to control treatment and displayed a cubic response regarding the environment. The age of the birds influenced the values of total protein, albumin, globulin, albumin:globulin (A:G) ratio, creatinine, GGT, and HDL. In conclusion, cyclical heat stress, at 36ºC, for one hour, from days 16 to 42 of age increases serum AST, whereas cholesterol and LDL-C levels increase only at day 21, indicating that birds may have adapted to heat stress. Age influenced the activity of AST and GGT and levels of creatinine, total protein, albumin, globulin, A:G ratio, cholesterol, HDL-C, and LDL-C.

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Cross-Generational Effects of Heat Stress on Fitness and Wolbachia Density in Aedes aegypti Mosquitoes

Tropical Medicine and Infectious Disease ◽

10.3390/tropicalmed4010013 ◽

2019 ◽

Vol 4 (1) ◽

pp. 13 ◽

Cited By ~ 9

Author(s):

Isabelle Jia-Hui Foo ◽

Ary A. Hoffmann ◽

Perran A. Ross

Keyword(s):

Heat Stress ◽

Aedes Aegypti ◽

Disease Transmission ◽

Wing Length ◽

Wolbachia Infection ◽

Female Offspring ◽

Starvation Tolerance ◽

Generational Effects ◽

Infection Types ◽

Wolbachia Density

Aedes aegypti mosquitoes infected with Wolbachia symbionts are now being released into the field to control the spread of pathogenic human arboviruses. Wolbachia can spread throughout vector populations by inducing cytoplasmic incompatibility and can reduce disease transmission by interfering with virus replication. The success of this strategy depends on the effects of Wolbachia on mosquito fitness and the stability of Wolbachia infections across generations. Wolbachia infections are vulnerable to heat stress, and sustained periods of hot weather in the field may influence their utility as disease control agents, particularly if temperature effects persist across generations. To investigate the cross-generational effects of heat stress on Wolbachia density and mosquito fitness, we subjected Ae. aegypti with two different Wolbachia infection types (wMel, wAlbB) and uninfected controls to cyclical heat stress during larval development over two generations. We then tested adult starvation tolerance and wing length as measures of fitness and measured the density of wMel in adults. Both heat stress and Wolbachia infection reduced adult starvation tolerance. wMel Wolbachia density in female offspring was lower when mothers experienced heat stress, but male Wolbachia density did not depend on the rearing temperature of the previous generation. We also found cross-generational effects of heat stress on female starvation tolerance, but there was no cross-generational effect on wing length. Fitness costs of Wolbachia infections and cross-generational effects of heat stress on Wolbachia density may reduce the ability of Wolbachia to invade populations and control arbovirus transmission under specific environmental conditions.

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Dopamine levels in the mosquito Aedes aegypti during adult development, following blood feeding and in response to heat stress

Journal of Insect Physiology ◽

10.1016/j.jinsphys.2006.08.004 ◽

2006 ◽

Vol 52 (11-12) ◽

pp. 1163-1170 ◽

Cited By ~ 25

Author(s):

Janne Pleidrup Andersen ◽

Alex Schwartz ◽

Jan Bert Gramsbergen ◽

Volker Loeschcke

Keyword(s):

Heat Stress ◽

Aedes Aegypti ◽

Adult Development ◽

Blood Feeding

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Wolbachia infections in Aedes aegypti differ markedly in their response to cyclical heat stress

10.1101/073106 ◽

2016 ◽

Cited By ~ 2

Author(s):

Perran A. Ross ◽

Itsanun Wiwatanaratanabutr ◽

Jason K. Axford ◽

Vanessa L. White ◽

Nancy M. Endersby-Harshman ◽

...

Keyword(s):

Aedes Aegypti ◽

Cytoplasmic Incompatibility ◽

Temperature Cycle ◽

High Fidelity ◽

Extreme Temperatures ◽

Sharp Reduction ◽

The World ◽

Different Types ◽

Two Generations ◽

Cyclical Heat

AbstractAedes aegypti mosquitoes infected with Wolbachia bacteria are currently being released for arbovirus suppression around the world. Their potential to invade populations and persist will depend on interactions with environmental conditions, particularly as larvae are often exposed to fluctuating and extreme temperatures in the field. We reared Ae. aegypti larvae infected with different types of Wolbachia (wMel, wAlbB and wMelPop) under diurnal cyclical temperatures. Rearing wMel and wMelPop-infected larvae at 26-37°C reduced the expression of cytoplasmic incompatibility, a reproductive manipulation induced by Wolbachia. We also observed a sharp reduction in the density of Wolbachia in adults. Furthermore, exposure to 26-37°C over two generations eliminated both the wMel and wMelPop infections. In contrast, the wAlbB infection was maintained at a high density, exhibited complete cytoplasmic incompatibility, and was transmitted from mother to offspring with a high fidelity under this temperature cycle. These findings have implications for the success of Wolbachia interventions across different environments and highlight the importance of temperature control in rearing.

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Heat shock protein 90 kDa (Hsp90) from Aedes aegypti has an open conformation and is expressed under heat stress

International Journal of Biological Macromolecules ◽

10.1016/j.ijbiomac.2020.04.029 ◽

2020 ◽

Vol 156 ◽

pp. 522-530

Author(s):

Natália G. Quel ◽

Glaucia M.S. Pinheiro ◽

Luiz Fernando de C. Rodrigues ◽

Leandro R.S. Barbosa ◽

Walid A. Houry ◽

...

Keyword(s):

Heat Stress ◽

Heat Shock ◽

Aedes Aegypti ◽

Heat Shock Protein ◽

Heat Shock Protein 90 ◽

Open Conformation

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Metarhizium robertsii protease and conidia production, response to heat stress and virulence against Aedes aegypti larvae

AMB Express ◽

10.1186/s13568-021-01326-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Juliana M. Ferreira ◽

Salorrane M. N. Pinto ◽

Filippe E. F. Soares

Keyword(s):

Heat Stress ◽

Abiotic Stress ◽

Aedes Aegypti ◽

Sodium Nitrate ◽

Culture Medium ◽

Stress Factors ◽

Metarhizium Robertsii ◽

Significant Difference ◽

Conidia Production ◽

Solid Fermentation

AbstractNutritional factors exert significant influence on the growth of entomopathogenic fungi, one of the main agents employed commercially in the biological control of arthropods. Thus, the objective of this work is to optimize the culture medium and solid fermentation time for production of proteases and conidia of Metarhizium robertsii ARSEF 2575 and to evaluate the interference of riboflavin and salts on virulence and resistance to abiotic stress factors. In the first step, nine groups were separated: negative control, positive control, and seven supplementation groups: ammonium nitrate, ammonium chloride, potassium nitrate, sodium nitrate, ammonium sulfate, ammonium phosphate, urea. Sodium nitrate showed significant difference in protease production at the time of 20 days of solid fermentation. Then, different concentrations of sodium nitrate and riboflavin as supplement were evaluated. Response surface methodology demonstrated that riboflavin and sodium nitrate influence proteolytic activity and conidia production, but without synergism. Supplementation of the medium with the optimal concentration of sodium nitrate and riboflavin did not interfere with the germination of conidia without exposure to abiotic stress, but did increase the thermotolerance of conidia. The presence of riboflavin and sodium nitrate at optimal concentrations in the culture medium did not alter fungal virulence with and without exposure to heat stress, varying according to the presence or absence of the supernatant during exposure, evidencing that resistance to heat exposure is multifactorial and dependent on intra- and extracellular factors. Moreover, the supplementation increased the larvicidal activity of the supernatant against Aedes aegypti.

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