It has been demonstrated that impairing protein synthesis using drugs targeted against tRNA amino acid synthetases presents a promising strategy for the treatment of a wide variety of parasitic diseases, including malaria and toxoplasmosis. This is the first study evaluating tRNA synthetases as potential drug targets in ticks. RNAi knock-down of all tested tRNA synthetases had a strong deleterious phenotype on Ixodes ricinus feeding. Our data indicate that tRNA synthetases represent attractive, anti-tick targets warranting the design of selective inhibitors. Further, we tested whether these severely impaired ticks were capable of transmitting Borrelia afzelii spirochaetes. Interestingly, biologically handicapped I. ricinus nymphs transmitted B. afzelii in a manner quantitatively sufficient to develop a systemic infection in mice. These data suggest that initial blood-feeding, despite the incapability of ticks to fully feed and salivate, is sufficient for activating B. afzelii from a dormant to an infectious mode, enabling transmission and dissemination in host tissues.

• MeSH
• akaricidy farmakologie   MeSH
• aminoacyl-tRNA-synthetasy antagonisté a inhibitory   genetika   MeSH
• Borrelia burgdorferi komplex MeSH
• klíšťata účinky léků   mikrobiologie   MeSH
• lidé MeSH
• lymeská nemoc farmakoterapie   mikrobiologie   přenos   MeSH
• proteosyntéza účinky léků   MeSH
• vyvíjení léků MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Stable endosymbiosis of a bacterium into a host cell promotes cellular and genomic complexity. The mealybug Planococcus citri has two bacterial endosymbionts with an unusual nested arrangement: the γ-proteobacterium Moranella endobia lives in the cytoplasm of the β-proteobacterium Tremblaya princeps These two bacteria, along with genes horizontally transferred from other bacteria to the P. citri genome, encode gene sets that form an interdependent metabolic patchwork. Here, we test the stability of this three-way symbiosis by sequencing host and symbiont genomes for five diverse mealybug species and find marked fluidity over evolutionary time. Although Tremblaya is the result of a single infection in the ancestor of mealybugs, the γ-proteobacterial symbionts result from multiple replacements of inferred different ages from related but distinct bacterial lineages. Our data show that symbiont replacement can happen even in the most intricate symbiotic arrangements and that preexisting horizontally transferred genes can remain stable on genomes in the face of extensive symbiont turnover.

• MeSH
• Betaproteobacteria genetika   růst a vývoj   MeSH
• fylogeneze MeSH
• Gammaproteobacteria genetika   růst a vývoj   MeSH
• genom bakteriální MeSH
• Planococcus (hmyz) genetika   mikrobiologie   MeSH
• přenos genů horizontální genetika   MeSH
• sekvenční analýza DNA MeSH
• symbióza genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH

BACKGROUND: Myxozoans are metazoan parasites whose traditional spore morphology-based taxonomy conflicts DNA based phylogenies. Freshwater species of the genus Hoferellus are parasites of the excretory system, with several members infecting food and ornamental fish species, as well as amphibians. This study aims to increase our understanding of their molecular diversity and development, aspects about which little is known, and to generate a molecular diagnostic tool to discriminate between different pathogenic and non-pathogenic Hoferellus spp. METHODS: SSU and ITS rDNA phylogeny, along with morphological descriptions using light and electron microscopy were used to identify and characterize Hoferellus species collected from the urinary system of fishes and frogs. A PCR-based diagnostic assay was designed to differentiate between cryptic Hoferellus spp in cyprinid fishes commonly cultured in Central Europe. RESULTS: Our phylogenetic results separate the species of Hoferellus into two phylogenetic sublineages which are indistinguishable on the basis of generic morphological traits: 1) The Hoferellus sensu stricto sublineage, which is composed of the type species Hoferellus cyprini, Hoferellus carassii and a cryptic species, Hoferellus sp. detected only molecularly in common carp. 2) The Hoferellus sensu lato sublineage into which the new species we described in this study, Hoferellus gnathonemi sp. n. from the kidney of the elephantnose fish and Hoferellus anurae from reed frogs, are placed together with Hoferellus gilsoni previously sequenced from European eel. Apart from phylogenetic analyses, we also provide novel ultrastructural data on the phagocytotic nature of some Hoferellus plasmodia and on the elusive intracellular stages ascribed to the presporogonic development of this genus. CONCLUSIONS: We provide molecular evidence of the polyphyly of the genus Hoferellus and provide novel morphological details of its members. Based on the presented data, we revise and propose emendation of the genus Hoferellus.

• MeSH
• Cyprinidae MeSH
• fylogeneze MeSH
• ledviny patologie   MeSH
• molekulární sekvence - údaje MeSH
• Myxozoa klasifikace   genetika   izolace a purifikace   ultrastruktura   MeSH
• nemoci ryb parazitologie   MeSH
• parazitární nemoci u zvířat parazitologie   MeSH
• ribozomální DNA chemie   genetika   MeSH
• sekvence nukleotidů MeSH
• sekvenční analýza DNA veterinární   MeSH
• žáby parazitologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH