Cardinium symbiosis as a potential confounder of mtDNA based phylogeographic inference in Culicoides imicola (Diptera: Ceratopogonidae), a vector of veterinary viruses. Parasit Vectors [Internet]. 2021;14(1):1–5
Authors:
HPRU-EZI Authors - Matthew Baylis
Abstract:
Background: Culicoides imicola (Diptera: Ceratopogonidae) is an important Afrotropical and Palearctic vector of disease, transmitting viruses of animal health and economic significance including African horse sickness and blue- tongue viruses. Maternally inherited symbiotic bacteria (endosymbionts) of arthropods can alter the frequency of COI (cytochrome c oxidase subunit I) mitochondrial haplotypes (mitotypes) in a population, masking the true patterns of host movement and gene flow. Thus, this study aimed to assess the mtDNA structure of C. imicola in relation to infec- tion with Candidatus Cardinum hertigii (Bacteroides), a common endosymbiont of Culicoides spp.
Methods: Using haplotype network analysis, COI Sanger sequences from Cardinium-infected and -uninfected C. imicola individuals were first compared in a population from South Africa. The network was then extended to include mitotypes from a geographic range where Cardinium infection has previously been investigated.
Results: The mitotype network of the South African population demonstrated the presence of two broad mitotype groups. All Cardinium-infected specimens fell into one group (Fisher’s exact test, P = 0.00071) demonstrating a link- age disequilibrium between endosymbiont and mitochondria. Furthermore, by extending this haplotype network to include other C. imicola populations from the Mediterranean basin, we revealed mitotype variation between the Eastern and Western Mediterranean basins (EMB and WMB) mirrored Cardinium-infection heterogeneity.
Conclusions: Keywords: Cardinium, Endosymbiont, Symbiosis, COI, Culicoides
Journal:
Parasites & Vectors
Hyperlink:
Research Themes:
3. Pathogen and Vector Biology