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Ixodes ricinus Tick Lipocalins: Identification, Cloning, Phylogenetic Analysis and Biochemical Characterization  [PDF]
Jér?me Beaufays, Beno?t Adam, Yves Decrem, Pierre-Paul Prév?t, Sébastien Santini, Robert Brasseur, Michel Brossard, Laurence Lins, Luc Vanhamme, Edmond Godfroid
PLOS ONE , 2008, DOI: 10.1371/journal.pone.0003941
Abstract: Background During their blood meal, ticks secrete a wide variety of proteins that interfere with their host's defense mechanisms. Among these proteins, lipocalins play a major role in the modulation of the inflammatory response. Methodology/Principal Findings Screening a cDNA library in association with RT-PCR and RACE methodologies allowed us to identify 14 new lipocalin genes in the salivary glands of the Ixodes ricinus hard tick. A computational in-depth structural analysis confirmed that LIRs belong to the lipocalin family. These proteins were called LIR for “Lipocalin from I. ricinus” and numbered from 1 to 14 (LIR1 to LIR14). According to their percentage identity/similarity, LIR proteins may be assigned to 6 distinct phylogenetic groups. The mature proteins have calculated pM and pI varying from 21.8 kDa to 37.2 kDa and from 4.45 to 9.57 respectively. In a western blot analysis, all recombinant LIRs appeared as a series of thin bands at 50–70 kDa, suggesting extensive glycosylation, which was experimentally confirmed by treatment with N-glycosidase F. In addition, the in vivo expression analysis of LIRs in I. ricinus, examined by RT-PCR, showed homogeneous expression profiles for certain phylogenetic groups and relatively heterogeneous profiles for other groups. Finally, we demonstrated that LIR6 codes for a protein that specifically binds leukotriene B4. Conclusions/Significance This work confirms that, regarding their biochemical properties, expression profile, and sequence signature, lipocalins in Ixodes hard tick genus, and more specifically in the Ixodes ricinus species, are segregated into distinct phylogenetic groups suggesting potential distinct function. This was particularly demonstrated by the ability of LIR6 to scavenge leukotriene B4. The other LIRs did not bind any of the ligands tested, such as 5-hydroxytryptamine, ADP, norepinephrine, platelet activating factor, prostaglandins D2 and E2, and finally leukotrienes B4 and C4.
Notas de ixodologia: III - conforma??o de Ixodes arag?oi Fonseca, 1935, de Ixodes amarali Fonseca, 1935, e lista das espécies do gênero Ixodes que ocorrem no Brasil (Acari, Ixodidae)
Arag?o, Henrique;Fonseca, Flavio da;
Memórias do Instituto Oswaldo Cruz , 1952, DOI: 10.1590/S0074-02761952000100025
Abstract: after comparison of the types of ixodes ricinus arag?oi fonseca, 1935, with a lot of ixodes affinis neumann, 1899, kindly loaned by dr. kohls, it was observed that both species differ by the aspect of the dorsal scutm, no large punctations being in the posterior border in the brazilian material. therefore is fonseca's species maintened as ixodes arag?oi fonseca, 1935. ixodes amarali fonseca, 1935 was reexamined and confirmed as a valid species. a list of brazilian species of the genus ixodes studied by the authors is presented.
Seasonal distribution of Borreliae in Ixodes ricinus ticks in the Belgrade region
Milutinovi? Marija,Radulovi? ?.,Tomanovi? Sne?ana,Tomanovi? ?.
Archives of Biological Sciences , 2006, DOI: 10.2298/abs0603183m
Abstract: Green areas at four localities in the Belgrade region (Ada Ciganlija, Ko utnjak, Miljakovac forest, and Mt. Avala) were investigated in 2004. The aim of the research was to clarify the faunistic composition, relative abundance, and population dynamics of ticks, as well as the seasonal distribution of Borrelia burgdorferi sensu lato (sl) in Ixodes ricinus. Two species of ticks were detected: Ixodes ricinus and Dermacentor reticulates. Relative abundance analysis revealed that the species Ixodes ricinus was predominant (97.41 %). Out of 942 Ixodes ricinus ticks, 188 (19.96 %) were infected with Borrelia burgdorferi sl. The infection rate of adults by localities ranged from 19.16% to 30.99% (Mt. Avala and Ada Ciganlija, respectively).
The Seasonal Activity of Ixodes ricinus Tick in Amol, Mazandaran Province, Northern Iran  [cached]
Nasrollah Vahedi-Noori,Sadegh Rahbari,Saeed Bokaei
Journal of Arthropod-Borne Diseases , 2012,
Abstract: Background: The present study aimed to demonstrate the seasonal activities of Ixodes ricinus at the pasture level and on the host.Methods: A vast pasture in Amol countryside (Mazandaran Province, Iran) which had the potential for a considerablenumber of cattle and sheep to graze was chosen. Tick sampling from the skin of 130 cattle and 130 sheep were collected every month interval. Simultaneously, the activity of the different stages of I. ricinus on the pasture was considered by dragging method. The collected ticks were placed in jars containing 70% alcohol and sent to the parasitological laboratory for identification.Results: The rate of the infestation with adult I. ricinus in cattle and sheep increases gradually with the beginning offall and reaches its peak in January, February and March while it starts to decline with the beginning of spring as theinfestation rate reach to zero in summer months. Accordingly, the highest number of adult I. ricinus existed on the cattle during January, February, and March. In addition, the results of dragging have been revealed that the active tick population in the pasture exists during November, December, January, and March.Conclusion: Ixodes ricinus is regarded a common tick species in Amol (Mazandaran). Due to the biological properties of I. ricinus which is active in the cold and humid months of the year, the prevalence of ruminant infestations with I. ricinus in this area increases from November to March but reaches to zero again with thebeginning of summer.
Insight into the sialome of the castor bean tick, Ixodes ricinus
Jind?ich Chmela?, Jennifer M Anderson, Jianbing Mu, Ryan C Jochim, Jesus G Valenzuela, Jan Kopecky
BMC Genomics , 2008, DOI: 10.1186/1471-2164-9-233
Abstract: In the attempt to describe expressed genes and their dynamics throughout the feeding period, we constructed cDNA libraries from four different feeding stages of Ixodes ricinus females: unfed, 24 hours after attachment, four (partially fed) and seven days (fully engorged) after attachment. Approximately 600 randomly selected clones from each cDNA library were sequenced and analyzed. From a total 2304 sequenced clones, 1881 sequences forming 1274 clusters underwent subsequent functional analysis using customized bioinformatics software. Clusters were sorted according to their predicted function and quantitative comparison among the four libraries was made. We found several groups of over-expressed genes associated with feeding that posses a secretion signal and may be involved in tick attachment, feeding or evading the host immune system. Many transcripts clustered into families of related genes with stage-specific expression. Comparison to Ixodes scapularis and I. pacificus transcripts was made.In addition to a large number of homologues of the known transcripts, we obtained several novel predicted protein sequences. Our work contributes to the growing list of proteins associated with tick feeding and sheds more light on the dynamics of the gene expression during tick feeding. Additionally, our results corroborate previous evidence of gene duplication in the evolution of ticks.Hard ticks (family Ixodidae) are well known ecto-parasites of vertebrates, with worldwide distribution and high medical importance due to their extraordinary ability to transmit various disease agents. Among hard ticks, the genus Ixodes is one of the most important vectors of human diseases. Lyme borreliosis, human granulocytic anaplasmosis (ehrlichiosis) and babesiosis are the main diseases transmitted by I. scapularis and I. pacificus in North America. In addition to these diseases, Ixodes ricinus in Europe and Ixodes persulcatus in Asia transmit tick-borne encephalitis (TBE). An increase of
Prevalence and diversity of Babesia spp. in questing Ixodes ricinus ticks from Norway
?ines ?ivind,Radzijevskaja Jana,Paulauskas Algimantas,Rosef Olav
Parasites & Vectors , 2012, DOI: 10.1186/1756-3305-5-156
Abstract: Background Ixodes ricinus ticks transmit Babesia species to vertebrate hosts. Using molecular tools we were able to detect the presence of this piroplasmid in its vector. The aims of this study were to investigate the prevalence and identity of Babesia species in questing ticks collected in various areas of Norway. Methods DNA from questing l. ricinus ticks were examined with a realtime PCR for the presence of Babesia. Positive samples of tick DNA were identified to species using PCR, and sequence analysis. Results From a total of 1908 questing l. ricinus ticks, 17 (0.9%) indicated the presence of Babesia spp. after realtime-PCR screening. Ixodes ricinus harbouring Babesia spp. was detected in 9 out of 22 localities. Further molecular analyses of DNA from these positive ticks indicate the presence of Babesia venatorum, B. divergens, B. capreoli and a currently undescribed Babesia in Norwegian ticks. The most prevalent was B. venatorum found in 71% of the positive ticks. Conclusions A total of 17 out of 1908 (0.9%) ticks were positive for Babesia. Our data confirm that there are several Babesia species in ticks in Norway. Babesia venatorum was the most prevalent. This species has a zoonotic potential and may cause human babesiosis following a tick bite.
Genetic Diversity of Salp15 in the Ixodes ricinus Complex (Acari: Ixodidae)  [PDF]
Xin Wang, Yong Huang, Si-bo Niu, Bao-Gui Jiang, Na Jia, Leo van der Geest, Xue-bing Ni, Yi Sun, Wu-Chun Cao
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0094131
Abstract: Salp15, a 15-kDa tick salivary gland protein, is both essential for ticks to successfully obtain host blood and also facilitates transmission of Lyme borreliosis. To determine whether the Salp15 gene is expressed in Ixodes persulcatus and Ixodes sinensis, principle vectors of Lyme borreliosis in China, we studied transcriptions of this gene in semi-engorged larvae, nymph and adults of these two species. A total of eight Salp15 homologues, five in I. persulcatus and three in I. sinensis, were identified by reverse transcriptase–polymerase chain reaction (RT-PCR). Interestingly, the intra-species similarity of Salp15 is approximately equal to its interspecies similarity and more than one Salp15 protein is expressed in a certain tick developmental stage. Comparison of DNA and proteins with other available tick Salp15 homologues suggests that the Salp15 superfamily is genetically conserved and diverse in the Ixodes ricinus complex. These findings indicate that Salp15 proteins in the I. ricinus complex may play an essential role in interacting with the host immune system and transmission of Borrelia genospecies.
Candidatus Neoehrlichia mikurensis in rodents in an area with sympatric existence of the hard ticks Ixodes ricinus and Dermacentor reticulatus, Germany  [cached]
Silaghi Cornelia,Woll Dietlinde,Mahling Monia,Pfister Kurt
Parasites & Vectors , 2012, DOI: 10.1186/1756-3305-5-285
Abstract: Background Candidatus Neoehrlichia mikurensis (CNM) has been described in the hard tick Ixodes ricinus and rodents as well as in some severe cases of human disease. The aims of this study were to identify DNA of CNM in small mammals, the ticks parasitizing them and questing ticks in areas with sympatric existence of Ixodes ricinus and Dermacentor reticulatus in Germany. Methods Blood, transudate and organ samples (spleen, kidney, liver, skin) of 91 small mammals and host-attached ticks from altogether 50 small mammals as well as questing I. ricinus ticks (n=782) were screened with a real-time PCR for DNA of CNM. Results 52.7% of the small mammals were positive for CNM-DNA. The majority of the infected animals were yellow-necked mice (Apodemus flavicollis) and bank voles (Myodes glareolus). Small mammals with tick infestation were more often infected with CNM than small mammals without ticks. Compared with the prevalence of ~25% in the questing I. ricinus ticks, twice the prevalence in the rodents provides evidence for their role as reservoir hosts for CNM. Conclusion The high prevalence of this pathogen in the investigated areas in both rodents and ticks points towards the need for more specific investigation on its role as a human pathogen.
Variability and Action Mechanism of a Family of Anticomplement Proteins in Ixodes ricinus  [PDF]
Bernard Couvreur, Jér?me Beaufays, Cédric Charon, Kathia Lahaye, Fran?ois Gensale, Valérie Denis, Beno?t Charloteaux, Yves Decrem, Pierre-Paul Prév?t, Michel Brossard, Luc Vanhamme, Edmond Godfroid
PLOS ONE , 2008, DOI: 10.1371/journal.pone.0001400
Abstract: Background Ticks are blood feeding arachnids that characteristically take a long blood meal. They must therefore counteract host defence mechanisms such as hemostasis, inflammation and the immune response. This is achieved by expressing batteries of salivary proteins coded by multigene families. Methodology/Principal Findings We report the in-depth analysis of a tick multigene family and describe five new anticomplement proteins in Ixodes ricinus. Compared to previously described Ixodes anticomplement proteins, these segregated into a new phylogenetic group or subfamily. These proteins have a novel action mechanism as they specifically bind to properdin, leading to the inhibition of C3 convertase and the alternative complement pathway. An excess of non-synonymous over synonymous changes indicated that coding sequences had undergone diversifying selection. Diversification was not associated with structural, biochemical or functional diversity, adaptation to host species or stage specificity but rather to differences in antigenicity. Conclusions/Significance Anticomplement proteins from I. ricinus are the first inhibitors that specifically target a positive regulator of complement, properdin. They may provide new tools for the investigation of role of properdin in physiological and pathophysiological mechanisms. They may also be useful in disorders affecting the alternative complement pathway. Looking for and detecting the different selection pressures involved will help in understanding the evolution of multigene families and hematophagy in arthropods.
First Molecular Detection of Anaplasma phagocytophilum in Ixodes ricinus Ticks in Iran  [PDF]
Hassan Bashiribod,Bahram Kazemi,Gita Eslami,Shahram Bigdeli
Journal of Medical Sciences , 2004,
Abstract: Lack of documented information and statistics about the prevalence of Anaplasma phagocytophilum, the causative agent of tick-borne Human Granulocytic Ehrlichiosis (HGE), in ticks, animals and also human beings in Iran, was the aim of this study to evaluate for the first time the infectivity rate of A. phagocytophilum in Ixodes ricinus ticks collected from a suburban woodland area in the eastern part of Ghaemshahr City in northern Iran. DNA was extracted from 98 unfed adult I. ricinus ticks (72 females and 26 males). Nested PCR Primers were designed based on Ehrlichia spp. 16S rDNA gene and PCR reaction was carried out. PCR product was detected using 254 nm UV Trans illuminator. For differentiation of Ehrlichia spp. RFLP technique was used. A. phagocytophilum 16S rDNA was detected in 5 (5.1%) of tested ticks. The positive ticks were 4 females and 1 male. The presence of A. phagocytophilum in the Iranian free-living I. ricinus ticks should alert our country to the possibility of HGE.
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