BACKGROUND: Although avian trypanosomes are widespread parasites, the knowledge of their vectors is still incomplete. Despite biting midges (Diptera: Ceratopogonidae) are considered as potential vectors of avian trypanosomes, their role in transmission has not been satisfactorily elucidated. Our aim was to clarify the potential of biting midges to sustain the development of avian trypanosomes by testing their susceptibility to different strains of avian trypanosomes experimentally. Moreover, we screened biting midges for natural infections in the wild. RESULTS: Laboratory-bred biting midges Culicoides nubeculosus were highly susceptible to trypanosomes from the Trypanosoma bennetti and T. avium clades. Infection rates reached 100%, heavy infections developed in 55-87% of blood-fed females. Parasite stages from the insect gut were infective for birds. Moreover, midges could be infected after feeding on a trypanosome-positive bird. Avian trypanosomes can thus complete their cycle in birds and biting midges. Furthermore, we succeeded to find infected blood meal-free biting midges in the wild. CONCLUSIONS: Biting midges are probable vectors of avian trypanosomes belonging to T. bennetti group. Midges are highly susceptible to artificial infections, can be infected after feeding on birds, and T. bennetti-infected biting midges (Culicoides spp.) have been found in nature. Moreover, midges can be used as model hosts producing metacyclic avian trypanosome stages infective for avian hosts.
- MeSH
- Ceratopogonidae anatomy & histology parasitology MeSH
- Gastrointestinal Tract parasitology MeSH
- Insect Vectors parasitology MeSH
- Host Specificity MeSH
- Canaries parasitology MeSH
- Microscopy, Electron, Scanning MeSH
- Bird Diseases parasitology transmission MeSH
- Polymerase Chain Reaction MeSH
- Birds parasitology MeSH
- Trypanosoma classification genetics physiology ultrastructure MeSH
- Trypanosomiasis diagnosis parasitology transmission veterinary MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
The transition zone (TZ) of eukaryotic cilia and flagella is a structural intermediate between the basal body and the axoneme that regulates ciliary traffic. Mutations in genes encoding TZ proteins (TZPs) cause human inherited diseases (ciliopathies). Here, we use the trypanosome to identify TZ components and localize them to TZ subdomains, showing that the Bardet-Biedl syndrome complex (BBSome) is more distal in the TZ than the Meckel syndrome (MKS) complex. Several of the TZPs identified here have human orthologs. Functional analysis shows essential roles for TZPs in motility, in building the axoneme central pair apparatus and in flagellum biogenesis. Analysis using RNAi and HaloTag fusion protein approaches reveals that most TZPs (including the MKS ciliopathy complex) show long-term stable association with the TZ, whereas the BBSome is dynamic. We propose that some Bardet-Biedl syndrome and MKS pleiotropy may be caused by mutations that impact TZP complex dynamics.
- MeSH
- Bardet-Biedl Syndrome genetics metabolism MeSH
- Basal Bodies metabolism ultrastructure MeSH
- Cilia genetics metabolism MeSH
- Ciliopathies genetics metabolism MeSH
- Cytoskeleton metabolism ultrastructure MeSH
- Encephalocele genetics metabolism MeSH
- Flagella genetics metabolism ultrastructure MeSH
- Microscopy, Fluorescence MeSH
- Cell Compartmentation MeSH
- Humans MeSH
- Mutation MeSH
- Polycystic Kidney Diseases genetics metabolism MeSH
- Ciliary Motility Disorders genetics metabolism MeSH
- Proteome genetics metabolism MeSH
- Protozoan Proteins genetics metabolism MeSH
- RNA Interference MeSH
- Microscopy, Electron, Transmission MeSH
- Trypanosoma genetics metabolism ultrastructure MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Establishing a health screening protocol is fundamental for successful captive breeding and release of wildlife. The aim of this study was to undertake a parasitological survey focusing on the presence of trypanosomes in a cohort of Regent Honeyeaters, Anthochaera phrygia, syn. Xanthomyza phrygia (Aves: Passeriformes) that are part of the breeding and reintroduction programme carried out in Australia. We describe a new blood parasite, Trypanosoma thomasbancrofti sp. n. (Kinetoplastida: Trypanosomatidae) with prevalence of 24·4% (20/81) in a captive population in 2015. The sequence of the small subunit rRNA gene (SSU rDNA) and kinetoplast ultrastructure of T. thomasbancrofti sp. n. are the key differentiating characteristics from other Trypanosoma spp. T. thomasbancrofti sp. n. is distinct from Trypanosoma cf. avium found in sympatric Noisy Miners (Manorina melanocephala). The SSU rDNA comparison suggests an intercontinental distribution of T. thomasbancrofti sp. n. and Culex mosquitoes as a suspected vector. Currently, no information exists on the effect of T. thomasbancrofti sp. n. on its hosts; however, all trypanosome-positive birds remain clinically healthy. This information is useful in establishing baseline health data and screening protocols, particularly prior to release to the wild.
- MeSH
- Phylogeny MeSH
- Bird Diseases parasitology MeSH
- Passeriformes parasitology MeSH
- DNA, Protozoan chemistry genetics MeSH
- DNA, Ribosomal chemistry genetics MeSH
- Sequence Analysis, DNA veterinary MeSH
- Trypanosoma genetics isolation & purification ultrastructure MeSH
- Conservation of Natural Resources MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- Australia MeSH
