Characterization of New Defensin Antimicrobial Peptides and Their Expression in Bed Bugs in Response to Bacterial Ingestion and Injection
Common bed bugs, <i>Cimex lectularius</i>, can carry, but do not transmit, pathogens to the vertebrate hosts on which they feed. Some components of the innate immune system of bed bugs, such as antimicrobial peptides (AMPs), eliminate the pathogens. Here, we determined the molecular char...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-09-01
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| Series: | International Journal of Molecular Sciences |
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| Online Access: | https://www.mdpi.com/1422-0067/23/19/11505 |
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| author | Sanam Meraj Arshvir Singh Dhari Emerson Mohr Carl Lowenberger Gerhard Gries |
| author_facet | Sanam Meraj Arshvir Singh Dhari Emerson Mohr Carl Lowenberger Gerhard Gries |
| author_sort | Sanam Meraj |
| collection | DOAJ |
| description | Common bed bugs, <i>Cimex lectularius</i>, can carry, but do not transmit, pathogens to the vertebrate hosts on which they feed. Some components of the innate immune system of bed bugs, such as antimicrobial peptides (AMPs), eliminate the pathogens. Here, we determined the molecular characteristics, structural properties, and phylogenetic relatedness of two new defensins (CL-defensin1 (XP_024085718.1), CL-defensin2 (XP_014240919.1)), and two new defensin isoforms (CL-defensin3a (XP_014240918.1), CL-defensin3b (XP_024083729.1)). The complete amino acid sequences of CL-defensin1, CL-defensin2, CL-defensin3a, and CL-defensin3b are strongly conserved, with only minor differences in their signal and pro-peptide regions. We used a combination of comparative transcriptomics and real-time quantitative PCR to evaluate the expression of these defensins in the midguts and the rest of the body of insects that had been injected with bacteria or had ingested blood containing the Gram-positive (Gr+) bacterium <i>Bacillus subtilis</i> and the Gram-negative (Gr–) bacterium <i>Escherichia coli</i>. We demonstrate, for the first time, sex-specific and immunization mode-specific upregulation of bed bug defensins in response to injection or ingestion of Gr+ or Gr– bacteria. Understanding the components, such as these defensins, of the bed bugs’ innate immune systems in response to pathogens may help unravel why bed bugs do not transmit pathogens to vertebrates. |
| first_indexed | 2024-03-09T21:40:08Z |
| format | Article |
| id | doaj.art-6a46b23dc907445c9ae47e8dc3cfab9a |
| institution | Directory Open Access Journal |
| issn | 1661-6596 1422-0067 |
| language | English |
| last_indexed | 2024-03-09T21:40:08Z |
| publishDate | 2022-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | International Journal of Molecular Sciences |
| spelling | doaj.art-6a46b23dc907445c9ae47e8dc3cfab9a2023-11-23T20:34:21ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672022-09-0123191150510.3390/ijms231911505Characterization of New Defensin Antimicrobial Peptides and Their Expression in Bed Bugs in Response to Bacterial Ingestion and InjectionSanam Meraj0Arshvir Singh Dhari1Emerson Mohr2Carl Lowenberger3Gerhard Gries4Department of Biological Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, CanadaDepartment of Biological Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, CanadaDepartment of Biological Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, CanadaDepartment of Biological Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, CanadaDepartment of Biological Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, CanadaCommon bed bugs, <i>Cimex lectularius</i>, can carry, but do not transmit, pathogens to the vertebrate hosts on which they feed. Some components of the innate immune system of bed bugs, such as antimicrobial peptides (AMPs), eliminate the pathogens. Here, we determined the molecular characteristics, structural properties, and phylogenetic relatedness of two new defensins (CL-defensin1 (XP_024085718.1), CL-defensin2 (XP_014240919.1)), and two new defensin isoforms (CL-defensin3a (XP_014240918.1), CL-defensin3b (XP_024083729.1)). The complete amino acid sequences of CL-defensin1, CL-defensin2, CL-defensin3a, and CL-defensin3b are strongly conserved, with only minor differences in their signal and pro-peptide regions. We used a combination of comparative transcriptomics and real-time quantitative PCR to evaluate the expression of these defensins in the midguts and the rest of the body of insects that had been injected with bacteria or had ingested blood containing the Gram-positive (Gr+) bacterium <i>Bacillus subtilis</i> and the Gram-negative (Gr–) bacterium <i>Escherichia coli</i>. We demonstrate, for the first time, sex-specific and immunization mode-specific upregulation of bed bug defensins in response to injection or ingestion of Gr+ or Gr– bacteria. Understanding the components, such as these defensins, of the bed bugs’ innate immune systems in response to pathogens may help unravel why bed bugs do not transmit pathogens to vertebrates.https://www.mdpi.com/1422-0067/23/19/11505bed bugsdefensin antimicrobial peptideshumoral innate immunityhematophagyToll and IMD pathwaysvectors |
| spellingShingle | Sanam Meraj Arshvir Singh Dhari Emerson Mohr Carl Lowenberger Gerhard Gries Characterization of New Defensin Antimicrobial Peptides and Their Expression in Bed Bugs in Response to Bacterial Ingestion and Injection International Journal of Molecular Sciences bed bugs defensin antimicrobial peptides humoral innate immunity hematophagy Toll and IMD pathways vectors |
| title | Characterization of New Defensin Antimicrobial Peptides and Their Expression in Bed Bugs in Response to Bacterial Ingestion and Injection |
| title_full | Characterization of New Defensin Antimicrobial Peptides and Their Expression in Bed Bugs in Response to Bacterial Ingestion and Injection |
| title_fullStr | Characterization of New Defensin Antimicrobial Peptides and Their Expression in Bed Bugs in Response to Bacterial Ingestion and Injection |
| title_full_unstemmed | Characterization of New Defensin Antimicrobial Peptides and Their Expression in Bed Bugs in Response to Bacterial Ingestion and Injection |
| title_short | Characterization of New Defensin Antimicrobial Peptides and Their Expression in Bed Bugs in Response to Bacterial Ingestion and Injection |
| title_sort | characterization of new defensin antimicrobial peptides and their expression in bed bugs in response to bacterial ingestion and injection |
| topic | bed bugs defensin antimicrobial peptides humoral innate immunity hematophagy Toll and IMD pathways vectors |
| url | https://www.mdpi.com/1422-0067/23/19/11505 |
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