This is a preprint, a preliminary version of a manuscript that has not completed peer review at a journal. Research Square does not conduct peer review prior to posting preprints. The posting of a preprint on this server should not be interpreted as an endorsement of its validity or suitability for dissemination as established information or for guiding clinical practice.
Research
Shune Oliver
National Institute for Communicable Diseases
Corresponding Author
ORCiD: https://orcid.org/0000-0003-0658-6658
License:
This work is licensed under a CC BY 4.0 License. Read Full License
Background
Anopheles arabiensis (a member of the An. gambiae species complex) is a major vector of malaria. These mosquitoes typically breed in clean bodies of water, but can also utilise polluted waters. Although this expands their breeding range, adaptation to breeding in polluted waters necessitates coping with a large amount of environmental stress in the form of exposure to heavy metal pollutants. Environmental stress can induce heritable changes to an organism without altering the basal genetic code. This occurs by rapid changes in the regulatory elements associated with nucleic acids that result in changes in patterns of gene expression and silencing. This is known as epigenetic regulation. There is currently little information on epigenetic regulation in An. arabiensis. The aim of this study was to examine whether exposure to metal pollutants at the larval stage induced alterations of epigenetic markers resulting in phenotypic changes in insecticide susceptible and resistant laboratory strains of An. arabiensis.
Results
There was a marked difference in the phenotypic response in adult mosquitoes of the insecticide susceptible strain compared to that of its’ resistant counterpart. The susceptible strain showed reduced fertility and fecundity in response to epigenetic manipulation. For males and females of the resistant strain, exposure to nucleic acid modifying drugs typically increased their tolerance to insecticides. In the insecticide susceptible strain, regulatory signals associated with gene silencing were increased, while those associated with gene expression were reduced in response to heavy metal exposure. By contrast, the insecticide resistant strain showed a decrease in signatures associated with gene silencing as well as an increase in signatures associate with chromatin remodelling.
Conclusions
Larval exposure to heavy metal contaminants can result in heritable changes in gene expression. These data suggest that exposure to the same pollutants can result in different biological outcomes in insecticide susceptible and resistant adult An. arabiensis, and that these changes are reflected in their respective global? epigenetic signatures.
Keywords
Anopheles arabiensis, Epigenetic, phenotypic, mosquitoes
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Loading...
Badges
Prescreen
This manuscript passed our Prescreen assessment
Complete author information
Appropriate declaration statements
Potential risks to human health
Prescreen
History
CURRENT STATUS: Posted
Version 1
Posted 30 Jul, 2020
No community comments so far
Metrics
Comments: 0
PDF Downloads: ...
HTML Views: ...
Subject Areas
Epigenetics & Genomics
Learn more about our company.
This is a preprint. It has not completed peer review.
Research
Shune Oliver
National Institute for Communicable Diseases
Corresponding Author
ORCiD: https://orcid.org/0000-0003-0658-6658
Badges
Prescreen
This manuscript passed our Prescreen assessment
Complete author information
Appropriate declaration statements
Potential risks to human health
Prescreen
History
CURRENT STATUS: Posted
Version 1
Posted 30 Jul, 2020
No community comments so far
Metrics
Comments: 0
PDF Downloads: ...
HTML Views: ...
Subject Areas
Epigenetics & Genomics
License:
This work is licensed under a CC BY 4.0 License. Read Full License
Background
Anopheles arabiensis (a member of the An. gambiae species complex) is a major vector of malaria. These mosquitoes typically breed in clean bodies of water, but can also utilise polluted waters. Although this expands their breeding range, adaptation to breeding in polluted waters necessitates coping with a large amount of environmental stress in the form of exposure to heavy metal pollutants. Environmental stress can induce heritable changes to an organism without altering the basal genetic code. This occurs by rapid changes in the regulatory elements associated with nucleic acids that result in changes in patterns of gene expression and silencing. This is known as epigenetic regulation. There is currently little information on epigenetic regulation in An. arabiensis. The aim of this study was to examine whether exposure to metal pollutants at the larval stage induced alterations of epigenetic markers resulting in phenotypic changes in insecticide susceptible and resistant laboratory strains of An. arabiensis.
Results
There was a marked difference in the phenotypic response in adult mosquitoes of the insecticide susceptible strain compared to that of its’ resistant counterpart. The susceptible strain showed reduced fertility and fecundity in response to epigenetic manipulation. For males and females of the resistant strain, exposure to nucleic acid modifying drugs typically increased their tolerance to insecticides. In the insecticide susceptible strain, regulatory signals associated with gene silencing were increased, while those associated with gene expression were reduced in response to heavy metal exposure. By contrast, the insecticide resistant strain showed a decrease in signatures associated with gene silencing as well as an increase in signatures associate with chromatin remodelling.
Conclusions
Larval exposure to heavy metal contaminants can result in heritable changes in gene expression. These data suggest that exposure to the same pollutants can result in different biological outcomes in insecticide susceptible and resistant adult An. arabiensis, and that these changes are reflected in their respective global? epigenetic signatures.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Loading...