首页 > 最新文献

International journal for parasitology最新文献

英文 中文
Evidence for a constitutive cost of host resistance on body fat growth in ewe lambs from lines selected for resistance or susceptibility to experimental infections with Haemonchus contortus. 有证据表明,宿主抗性对母羊羔羊体脂增长的构成性成本来自于对实验性传染性口蹄疫感染的抗性或易感性选育出的品系。
IF 3.7 2区 医学 Q1 PARASITOLOGY Pub Date : 2024-09-26 DOI: 10.1016/j.ijpara.2024.09.004
Frédéric Douhard, Xavier Matthey, Didier Marcon, Camille Coffre-Thomain, Lucie Estivalet, Delphine Serreau, Fabrice Guégnard, Guillaume Sallé, Papa Moussa Drame, Frédéric Elleboudt, François Lecompte, Hans Adriaensen

Although benefits of selection for host resistance to gastro-intestinal nematodes have long been recognized, its costs on production traits remain unclear. A main difficulty when studying those costs is to disentangle genetic effects due to selection from plastic responses induced by infection. Putative costs of host resistance have been extensively investigated in growing sheep. However, while most of those studies have relied on live weight to assess body growth, more comprehensive assessments accounting for body composition are advocated to detect trade-offs. In this study we used 90 female lambs from lines divergently selected on resistance to Haemonchus contortus that we experimentally infected (n = 60) or not (n = 30) under controlled conditions. As those conditions were defined to enable uninfected lambs to fully express their growth potential, we sought to precisely identify the effects of selection for host resistance on health traits and on growth traits. We assessed muscular and fat growth based on repeated measurements with dorsal ultrasonography for all lambs on farm, and with whole-body computed tomography (CT) scans for a subgroup of 18 infected lambs. Lambs achieved a high growth rate, including infected ones despite their high worm burden (confirmed at necropsy in the subgroup). As expected, lambs from the resistant (R) line were less infected than those from the susceptible (S) line. However, the clear pathogenic effects observed on muscular growth and voluntary feed intake were similar between lines. In contrast, a line difference in body fat was supported both by dorsal and volumetric CT measurements. Specifically, lower fat in the R line compared with the S line was observed equally in infected and uninfected groups, thus providing evidence for a constitutive cost of host resistance. Although this cost is not necessarily disadvantageous in nutrient-rich environments exposing animals to excess fat deposition, its consequences in nutrient-scarce environments may be important to promote sustainable breeding strategies for host resistance.

尽管宿主对胃肠道线虫的抗性选择所带来的益处早已得到认可,但其对生产性状所造成的代价仍不清楚。研究这些成本的一个主要困难是如何将选择的遗传效应与感染引起的可塑性反应区分开来。在绵羊生长过程中,对宿主抗性的成本进行了广泛研究。然而,虽然这些研究大多依赖活重来评估身体生长情况,但我们主张对身体组成进行更全面的评估,以检测权衡。在这项研究中,我们使用了 90 只雌性羔羊,这些羔羊来自对血包虫病具有抗性的不同选育品系,我们在受控条件下对它们进行了感染(n = 60)或不感染(n = 30)的实验。由于这些条件是为了让未感染的羔羊充分发挥其生长潜力,因此我们试图精确确定宿主抗性选择对健康性状和生长性状的影响。我们对农场所有羔羊的肌肉和脂肪生长情况进行了评估,这些评估是通过背侧超声波重复测量进行的,并对 18 只受感染羔羊进行了全身计算机断层扫描(CT)。羔羊的生长率很高,包括受感染的羔羊,尽管它们的虫体负担很重(在子组的尸体解剖中得到证实)。不出所料,抗性(R)品系羔羊的感染率低于易感(S)品系羔羊。然而,在肌肉生长和自愿采食量方面观察到的明显致病影响在不同品系之间是相似的。与此相反,体脂的品系差异得到了背侧和容积 CT 测量的支持。具体来说,与 S 系相比,R 系的脂肪较低,这一点在感染组和未感染组中都能观察到,从而为宿主抵抗力的构成代价提供了证据。虽然在营养丰富的环境中,这种代价不一定会使动物脂肪沉积过多,但在营养匮乏的环境中,其后果可能对促进可持续的抗宿主育种策略非常重要。
{"title":"Evidence for a constitutive cost of host resistance on body fat growth in ewe lambs from lines selected for resistance or susceptibility to experimental infections with Haemonchus contortus.","authors":"Frédéric Douhard, Xavier Matthey, Didier Marcon, Camille Coffre-Thomain, Lucie Estivalet, Delphine Serreau, Fabrice Guégnard, Guillaume Sallé, Papa Moussa Drame, Frédéric Elleboudt, François Lecompte, Hans Adriaensen","doi":"10.1016/j.ijpara.2024.09.004","DOIUrl":"10.1016/j.ijpara.2024.09.004","url":null,"abstract":"<p><p>Although benefits of selection for host resistance to gastro-intestinal nematodes have long been recognized, its costs on production traits remain unclear. A main difficulty when studying those costs is to disentangle genetic effects due to selection from plastic responses induced by infection. Putative costs of host resistance have been extensively investigated in growing sheep. However, while most of those studies have relied on live weight to assess body growth, more comprehensive assessments accounting for body composition are advocated to detect trade-offs. In this study we used 90 female lambs from lines divergently selected on resistance to Haemonchus contortus that we experimentally infected (n = 60) or not (n = 30) under controlled conditions. As those conditions were defined to enable uninfected lambs to fully express their growth potential, we sought to precisely identify the effects of selection for host resistance on health traits and on growth traits. We assessed muscular and fat growth based on repeated measurements with dorsal ultrasonography for all lambs on farm, and with whole-body computed tomography (CT) scans for a subgroup of 18 infected lambs. Lambs achieved a high growth rate, including infected ones despite their high worm burden (confirmed at necropsy in the subgroup). As expected, lambs from the resistant (R) line were less infected than those from the susceptible (S) line. However, the clear pathogenic effects observed on muscular growth and voluntary feed intake were similar between lines. In contrast, a line difference in body fat was supported both by dorsal and volumetric CT measurements. Specifically, lower fat in the R line compared with the S line was observed equally in infected and uninfected groups, thus providing evidence for a constitutive cost of host resistance. Although this cost is not necessarily disadvantageous in nutrient-rich environments exposing animals to excess fat deposition, its consequences in nutrient-scarce environments may be important to promote sustainable breeding strategies for host resistance.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142346128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Parasite β-diversity along a stream: effect of distance and environment. 溪流寄生虫的β多样性:距离和环境的影响。
IF 3.7 2区 医学 Q1 PARASITOLOGY Pub Date : 2024-09-25 DOI: 10.1016/j.ijpara.2024.09.002
Verónica Taglioretti, María Alejandra Rossin, Eugenia Levy, Juan Tomás Timi

Parasites can provide suitable models for studying β-diversity due to their strict dependence on both the environment and the biology and distribution of their hosts, aiding in the interpretation of any patterns that hosts can display. With the aim of quantifying the relative importance of host features, environmental factors and spatial distances as drivers of fish parasite β-diversity along a unidirectional gradient, the structure of fish parasite assemblages was analysed using generalised dissimilarity models (GDMs). A total of 150 poeciliid fish were examined for larval trematodes, recording host features and physical parameters of each sampling site along the stream. Differences among digenean communities increased when Strahler order changed along the stream, associated with increasing species richness and abundance downstream. Environmental gradient, spatial distance and host features were identified as significant determining factors of species turnover, with conductivity being the most important, followed by spatial distance. In the present study, environmental variables were spatially structured along the stream, their effects as structurers of parasite β-diversity being higher than the pure environmental or the pure distance effect. Such predominance prevents us from establishing at what point on the continuum from niche to neutrality these communities are located. Results from the present research contribute to improving our knowledge of the factors that shape parasite community changes, and underline the importance of considering the pure and shared effects of spatial, environmental and host feature factors in order to determine the real contribution of each one as a determinant of parasite β- diversity.

由于寄生虫严格依赖于环境及其宿主的生物学和分布,因此寄生虫可以为研究β多样性提供合适的模型,有助于解释宿主可能显示的任何模式。为了量化宿主特征、环境因素和空间距离作为单向梯度鱼类寄生虫β多样性驱动因素的相对重要性,我们使用广义相似性模型(GDMs)分析了鱼类寄生虫群的结构。共对 150 条poeciliid 鱼进行了幼虫吸虫检查,并记录了溪流沿岸每个采样点的寄主特征和物理参数。当溪流的斯特雷勒顺序发生变化时,地衣类群落之间的差异也随之增加,这与下游物种丰富度和丰度的增加有关。环境梯度、空间距离和寄主特征被认为是物种更替的重要决定因素,其中电导率最为重要,空间距离次之。在本研究中,环境变量沿溪流呈空间结构分布,它们对寄生虫 β 多样性的影响高于纯环境或纯距离的影响。这种优势使我们无法确定这些群落位于从利基到中性的连续统一体的哪一个点上。本研究的结果有助于提高我们对影响寄生虫群落变化的因素的认识,并强调了考虑空间、环境和宿主特征因素的纯效应和共同效应的重要性,以便确定每种因素作为寄生虫β多样性决定因素的真正贡献。
{"title":"Parasite β-diversity along a stream: effect of distance and environment.","authors":"Verónica Taglioretti, María Alejandra Rossin, Eugenia Levy, Juan Tomás Timi","doi":"10.1016/j.ijpara.2024.09.002","DOIUrl":"10.1016/j.ijpara.2024.09.002","url":null,"abstract":"<p><p>Parasites can provide suitable models for studying β-diversity due to their strict dependence on both the environment and the biology and distribution of their hosts, aiding in the interpretation of any patterns that hosts can display. With the aim of quantifying the relative importance of host features, environmental factors and spatial distances as drivers of fish parasite β-diversity along a unidirectional gradient, the structure of fish parasite assemblages was analysed using generalised dissimilarity models (GDMs). A total of 150 poeciliid fish were examined for larval trematodes, recording host features and physical parameters of each sampling site along the stream. Differences among digenean communities increased when Strahler order changed along the stream, associated with increasing species richness and abundance downstream. Environmental gradient, spatial distance and host features were identified as significant determining factors of species turnover, with conductivity being the most important, followed by spatial distance. In the present study, environmental variables were spatially structured along the stream, their effects as structurers of parasite β-diversity being higher than the pure environmental or the pure distance effect. Such predominance prevents us from establishing at what point on the continuum from niche to neutrality these communities are located. Results from the present research contribute to improving our knowledge of the factors that shape parasite community changes, and underline the importance of considering the pure and shared effects of spatial, environmental and host feature factors in order to determine the real contribution of each one as a determinant of parasite β- diversity.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142346129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The invasive acanthocephalan parasite Pachysentis canicola is associated with a declining endemic island fox population on San Miguel Island. 入侵的棘头蚴寄生虫 Pachysentis canicola 与圣米格尔岛上的特有岛狐数量下降有关。
IF 3.7 2区 医学 Q1 PARASITOLOGY Pub Date : 2024-09-24 DOI: 10.1016/j.ijpara.2024.09.003
O Alejandro Aleuy, Leslie W Woods, Benjamin J Padilla, Dennis Richardson, Juliann T Schamel, Stacy Baker, Martín García-Varela, Charlotte Hammond, Sarah P Lawson, Jasmine N Childress, Jason Rohr, Kevin D Lafferty

In the late 1990s, the San Miguel Island fox (Urocyon littoralis littoralis) faced near-extinction. Fourteen of the 15 remaining foxes were placed into an island-based captive breeding program used to repopulate the island. Although the fox population in San Miguel reached pre-decline numbers by 2010, a second decline started around 2014, coincidental with a newly observed acanthocephalan parasite. To identify this introduced acanthocephalan species and determine the pathologic consequences of its infection on the health of foxes, we used an extensive record of island fox necropsies and associated parasite collections. In addition, we used detailed fox capture-recapture data to investigate population health and demographic trends of foxes before and after parasite emergence. We identify the parasite as Pachysentis canicola, a common acanthocephalan in mainland foxes in North America. The parasite was detected in 69% of the necropsied foxes from San Miguel Island and was not found in any of the other five Channel Island fox subspecies. Health impacts attributed to the acanthocephalan parasite, including erosive and ulcerative enteritis, transmural necrosis, and inflammation, were described in 47% of the foxes infected with the acanthocephalan. Despite infection with various other helminth parasite species, body condition remained good and the mortality rate low in San Miguel Island foxes until the arrival of the acanthocephalan. Body condition improved after 2018, perhaps due to increases in rainfall following a drought, but remained 27% lower than the pre-acanthocephalan period, which suggests that environmental conditions and parasitism jointly drive fox population dynamics.

20 世纪 90 年代末,圣米格尔岛狐(Urocyon littoralis littoralis)濒临灭绝。在仅存的 15 只狐狸中,有 14 只被放入岛上的圈养繁殖计划中,用于重新繁殖岛上的狐狸。虽然圣米格尔岛的狐狸数量在 2010 年达到了衰退前的水平,但在 2014 年左右又开始了第二次衰退,这与一种新观察到的棘头蚴寄生虫不谋而合。为了确定这种引入的棘头蚴物种,并确定其感染对狐狸健康造成的病理后果,我们使用了大量的岛上狐狸尸体解剖记录和相关寄生虫采集记录。此外,我们还利用详细的狐狸捕获再捕获数据,调查了寄生虫出现前后狐狸的种群健康状况和人口趋势。我们确定寄生虫为 Pachysentis canicola,这是北美大陆狐狸中常见的棘头蚴。在圣米格尔岛 69% 的尸体解剖狐狸中检测到了这种寄生虫,而在海峡岛其他五个狐狸亚种中均未发现。47%感染棘头蚴寄生虫的狐狸的健康受到了影响,包括侵蚀性和溃疡性肠炎、跨膜坏死和炎症。尽管感染了其他多种蠕虫寄生虫,但在棘头蚴到来之前,圣米格尔岛狐狸的身体状况一直很好,死亡率也很低。2018 年后,身体状况有所改善,这可能是由于干旱后降雨量增加所致,但仍比尖头蚴感染前低 27%,这表明环境条件和寄生虫共同驱动着狐狸的种群动态。
{"title":"The invasive acanthocephalan parasite Pachysentis canicola is associated with a declining endemic island fox population on San Miguel Island.","authors":"O Alejandro Aleuy, Leslie W Woods, Benjamin J Padilla, Dennis Richardson, Juliann T Schamel, Stacy Baker, Martín García-Varela, Charlotte Hammond, Sarah P Lawson, Jasmine N Childress, Jason Rohr, Kevin D Lafferty","doi":"10.1016/j.ijpara.2024.09.003","DOIUrl":"10.1016/j.ijpara.2024.09.003","url":null,"abstract":"<p><p>In the late 1990s, the San Miguel Island fox (Urocyon littoralis littoralis) faced near-extinction. Fourteen of the 15 remaining foxes were placed into an island-based captive breeding program used to repopulate the island. Although the fox population in San Miguel reached pre-decline numbers by 2010, a second decline started around 2014, coincidental with a newly observed acanthocephalan parasite. To identify this introduced acanthocephalan species and determine the pathologic consequences of its infection on the health of foxes, we used an extensive record of island fox necropsies and associated parasite collections. In addition, we used detailed fox capture-recapture data to investigate population health and demographic trends of foxes before and after parasite emergence. We identify the parasite as Pachysentis canicola, a common acanthocephalan in mainland foxes in North America. The parasite was detected in 69% of the necropsied foxes from San Miguel Island and was not found in any of the other five Channel Island fox subspecies. Health impacts attributed to the acanthocephalan parasite, including erosive and ulcerative enteritis, transmural necrosis, and inflammation, were described in 47% of the foxes infected with the acanthocephalan. Despite infection with various other helminth parasite species, body condition remained good and the mortality rate low in San Miguel Island foxes until the arrival of the acanthocephalan. Body condition improved after 2018, perhaps due to increases in rainfall following a drought, but remained 27% lower than the pre-acanthocephalan period, which suggests that environmental conditions and parasitism jointly drive fox population dynamics.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142346130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Molecular characterisation of Australasian Ixodiphagus (Hymenoptera; Encyrtidae; Encyrtinae) reveals unexpected diversity and a potential novel host switch. 澳大拉西亚 Ixodiphagus(膜翅目;Encyrtidae;Encyrtinae)的分子特征揭示了意想不到的多样性和潜在的新型宿主转换。
IF 3.7 2区 医学 Q1 PARASITOLOGY Pub Date : 2024-09-11 DOI: 10.1016/j.ijpara.2024.09.001
Madalene M Giannotta, Ina Smith, Michelle Michie, Kim Blasdell, Mike Dunn, James Nicholls, Allen C G Heath, Juanita Rodriguez, Alexander W Gofton

Ticks are important medical and veterinary parasites that represent a substantial health threat to humans, companion animals, and livestock. Ixodiphagus wasps (Hymenoptera; Encyrtidae) are known endoparasitoids of ixodid (hard) and argasid (soft) ticks, with potential utility as natural biocontrol agents. Two species, Ixodiphagus brunneus and Ixodiphagus mysorensis, are previously recorded from Australia, however, the genus lacks formal revisionary work in Australia, and the validity and host ranges of these species remain uncertain. This work aimed to investigate the diversity of Ixodiphagus in Australasia and provide a molecular data resource for future work on these understudied endoparasitoids. We extracted DNA from archival Ixodiphagus specimens from Australian and New Zealand insect collections and performed high-throughput sequencing which resulted in complete or mostly complete mitochondrial genome sequences from 11 specimens, including I. brunneus, Ixodiphagus taiaroaensis, and a novel Ixodiphagus sp. reared from Rhipicephalus linnaei from Townsville, Australia. In addition, approximately 70% of the genome of the Wolbachia endosymbiont of I. brunneus was recovered. Finally, we screened 178 recently collected pooled tick samples from southern New South Wales, Australia, for Ixodiphagus spp. using 28S rRNA and cytochrome c oxidase subunit 1(COI) gene PCR, and recovered 14 positive samples. Phylogenetic analysis of Australasian Ixodiphagus spp. based on 28S rRNA and complete mitochondrial genome sequences determined that members of the Australasian fauna are distinct from Ixodiphagus hookeri (the only other Ixodiphagus species for which genetic data exists), and that at least two distinct species are present in Australia; I. brunneus identified from Ixodes holocyclus and Haemaphysalis bancrofti ticks, and an uncharacterised Ixodiphagus sp. found in Rhipicephalus linnaei ticks from northern Queensland. Furthermore, there was substantial genetic diversity at the 28S rRNA loci among I. brunneus samples, which may represent normal genetic variability or a secondary cryptic species. The molecular data generated here represents the first known for the genus Ixodiphagus in Australasia, doubling that of the world fauna, and provides the first known complete mitochondrial genomes for these important tick parasitoids.

蜱是重要的医学和兽医寄生虫,对人类、伴侣动物和牲畜的健康构成严重威胁。Ixodiphagus 黄蜂(膜翅目;Encyrtidae)是已知的蜱(硬蜱)和蜱(软蜱)的内寄生虫,具有天然生物控制剂的潜在用途。澳大利亚以前曾记录过两个物种,即 Ixodiphagus brunneus 和 Ixodiphagus mysorensis,但该属在澳大利亚缺乏正式的修订工作,这些物种的有效性和宿主范围仍不确定。这项研究旨在调查澳大拉西亚 Ixodiphagus 的多样性,并为今后研究这些研究不足的内寄生虫提供分子数据资源。我们从澳大利亚和新西兰昆虫馆藏的 Ixodiphagus 标本中提取了 DNA,并进行了高通量测序,从而获得了 11 个标本的完整或基本完整的线粒体基因组序列,其中包括 I. brunneus、Ixodiphagus taiaroaensis,以及从澳大利亚汤斯维尔的 Rhipicephalus linnaei 上饲养的新型 Ixodiphagus sp.。此外,我们还恢复了布鲁内斯虹鳟 Wolbachia 内共生体约 70% 的基因组。最后,我们利用 28S rRNA 和细胞色素 c 氧化酶亚单位 1(COI)基因 PCR 技术对最近从澳大利亚新南威尔士州南部采集的 178 份蜱样本进行了筛选,发现了 14 份阳性样本。基于 28S rRNA 和完整线粒体基因组序列的澳大拉西亚 Ixodiphagus spp.系统进化分析表明,澳大拉西亚动物群的成员与 Ixodiphagus hookeri(唯一有遗传数据的其他 Ixodiphagus 物种)不同,澳大利亚至少有两个不同的物种:I.从 Ixodes holocyclus 和 Haemaphysalis bancrofti 的蜱虫中发现了 Ixodiphagus brunneus,从昆士兰北部的 Rhipicephalus linnaei 的蜱虫中发现了一种未定性的 Ixodiphagus sp.。此外,在 I. brunneus 样本中,28S rRNA 位点存在大量遗传多样性,这可能代表正常的遗传变异或次生隐性物种。这里产生的分子数据是已知澳大拉西亚 Ixodiphagus 属的第一个数据,是世界动物群的两倍,并为这些重要的蜱寄生虫提供了第一个已知的完整线粒体基因组。
{"title":"Molecular characterisation of Australasian Ixodiphagus (Hymenoptera; Encyrtidae; Encyrtinae) reveals unexpected diversity and a potential novel host switch.","authors":"Madalene M Giannotta, Ina Smith, Michelle Michie, Kim Blasdell, Mike Dunn, James Nicholls, Allen C G Heath, Juanita Rodriguez, Alexander W Gofton","doi":"10.1016/j.ijpara.2024.09.001","DOIUrl":"https://doi.org/10.1016/j.ijpara.2024.09.001","url":null,"abstract":"<p><p>Ticks are important medical and veterinary parasites that represent a substantial health threat to humans, companion animals, and livestock. Ixodiphagus wasps (Hymenoptera; Encyrtidae) are known endoparasitoids of ixodid (hard) and argasid (soft) ticks, with potential utility as natural biocontrol agents. Two species, Ixodiphagus brunneus and Ixodiphagus mysorensis, are previously recorded from Australia, however, the genus lacks formal revisionary work in Australia, and the validity and host ranges of these species remain uncertain. This work aimed to investigate the diversity of Ixodiphagus in Australasia and provide a molecular data resource for future work on these understudied endoparasitoids. We extracted DNA from archival Ixodiphagus specimens from Australian and New Zealand insect collections and performed high-throughput sequencing which resulted in complete or mostly complete mitochondrial genome sequences from 11 specimens, including I. brunneus, Ixodiphagus taiaroaensis, and a novel Ixodiphagus sp. reared from Rhipicephalus linnaei from Townsville, Australia. In addition, approximately 70% of the genome of the Wolbachia endosymbiont of I. brunneus was recovered. Finally, we screened 178 recently collected pooled tick samples from southern New South Wales, Australia, for Ixodiphagus spp. using 28S rRNA and cytochrome c oxidase subunit 1(COI) gene PCR, and recovered 14 positive samples. Phylogenetic analysis of Australasian Ixodiphagus spp. based on 28S rRNA and complete mitochondrial genome sequences determined that members of the Australasian fauna are distinct from Ixodiphagus hookeri (the only other Ixodiphagus species for which genetic data exists), and that at least two distinct species are present in Australia; I. brunneus identified from Ixodes holocyclus and Haemaphysalis bancrofti ticks, and an uncharacterised Ixodiphagus sp. found in Rhipicephalus linnaei ticks from northern Queensland. Furthermore, there was substantial genetic diversity at the 28S rRNA loci among I. brunneus samples, which may represent normal genetic variability or a secondary cryptic species. The molecular data generated here represents the first known for the genus Ixodiphagus in Australasia, doubling that of the world fauna, and provides the first known complete mitochondrial genomes for these important tick parasitoids.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142286308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Exploring dietary differences among developmental stages of triatomines infected with Trypanosoma cruzi in different habitats 探索不同栖息地感染了克鲁兹锥虫的三足虫各发育阶段的饮食差异。
IF 3.7 2区 医学 Q1 PARASITOLOGY Pub Date : 2024-09-01 DOI: 10.1016/j.ijpara.2024.05.001

Chagas disease affects millions of people in Colombia and worldwide, with its transmission influenced by ecological, environmental, and anthropogenic factors. There is a notable correlation between vector transmission cycles and the habitats of insect vectors of the parasite. However, the scale at which these cycles operate remains uncertain. While individual triatomine ecotopes such as palms provide conditions for isolated transmission cycles, recent studies examining triatomine blood sources in various habitats suggest a more intricate network of transmission cycles, linking wild ecotopes with human dwellings. This study aims to provide further evidence on the complexity of the scale of Trypanosoma cruzi transmission cycles, by exploring the different blood sources among developmental stages of infected triatomines in different habitats. We evaluated infection rates, parasite loads, feeding sources, and the distribution of Rhodnius prolixus insects in Attalea butyracea palms across three distinct habitats in Casanare, Colombia: peridomestics, pastures, and woodlands. Our results show that there is no clear independence in transmission cycles in each environment. Analyses of feeding sources suggest the movement of insects and mammals (primarily bats and didelphids) among habitats. A significant association was found between habitat and instar stages in collected R. prolixus. The N1 stage was correlated with pasture and woodland, while the N4 stage was related to pasture. Additionally, adult insects exhibited higher T. cruzi loads than N1, N2, and N3. We observed higher T. cruzi loads in insects captured in dwelling and pasture habitats, compared with those captured in woodland areas. Effective Chagas disease control strategies must consider the complexity of transmission cycles and the interplay between domestic and sylvatic populations of mammals and vectors.

南美锥虫病影响着哥伦比亚和全世界数百万人,其传播受生态、环境和人为因素的影响。病媒传播周期与寄生虫昆虫病媒的栖息地之间存在明显的相关性。然而,这些周期的运作规模仍不确定。虽然棕榈树等个别三蠹生态群落为孤立的传播周期提供了条件,但最近对不同栖息地的三蠹血源进行的研究表明,传播周期网络更加错综复杂,将野生生态群落与人类居住地联系在一起。本研究旨在通过探究不同栖息地中受感染三蠹发育阶段的不同血液来源,进一步证明克氏锥虫传播周期规模的复杂性。我们评估了哥伦比亚卡萨纳雷三种不同栖息地(围牧场、牧场和林地)的感染率、寄生虫量、食源以及Attalea butyracea棕榈中Rhodnius prolixus昆虫的分布情况。我们的研究结果表明,每种环境中的传播周期都没有明显的独立性。对食物来源的分析表明,昆虫和哺乳动物(主要是蝙蝠和蚜虫)在不同的栖息地之间流动。在采集到的 R. prolixus 中,栖息地与分化阶段之间存在明显的关联。N1 阶段与牧场和林地相关,而 N4 阶段与牧场相关。此外,与 N1、N2 和 N3 相比,成虫表现出更高的 T. cruzi 负荷。我们观察到,与在林地捕获的昆虫相比,在住所和牧场捕获的昆虫体内有更高的南美锥虫病病毒载量。有效的南美锥虫病控制策略必须考虑到传播周期的复杂性,以及哺乳动物和病媒在家养种群和草原种群之间的相互作用。
{"title":"Exploring dietary differences among developmental stages of triatomines infected with Trypanosoma cruzi in different habitats","authors":"","doi":"10.1016/j.ijpara.2024.05.001","DOIUrl":"10.1016/j.ijpara.2024.05.001","url":null,"abstract":"<div><p>Chagas disease affects millions of people in Colombia and worldwide, with its transmission influenced by ecological, environmental, and anthropogenic factors. There is a notable correlation between vector transmission cycles and the habitats of insect vectors of the parasite. However, the scale at which these cycles operate remains uncertain. While individual triatomine ecotopes such as palms provide conditions for isolated transmission cycles, recent studies examining triatomine blood sources in various habitats suggest a more intricate network of transmission cycles, linking wild ecotopes with human dwellings. This study aims to provide further evidence on the complexity of the scale of <em>Trypanosoma cruzi</em> transmission cycles, by exploring the different blood sources among developmental stages of infected triatomines in different habitats. We evaluated infection rates, parasite loads, feeding sources, and the distribution of <em>Rhodnius prolixus</em> insects in <em>Attalea butyracea</em> palms across three distinct habitats in Casanare, Colombia: peridomestics, pastures, and woodlands. Our results show that there is no clear independence in transmission cycles in each environment. Analyses of feeding sources suggest the movement of insects and mammals (primarily bats and didelphids) among habitats. A significant association was found between habitat and instar stages in collected <em>R. prolixus</em>. The N1 stage was correlated with pasture and woodland, while the N4 stage was related to pasture. Additionally, adult insects exhibited higher <em>T. cruzi</em> loads than N1, N2, and N3. We observed higher <em>T. cruzi</em> loads in insects captured in dwelling and pasture habitats, compared with those captured in woodland areas. Effective Chagas disease control strategies must consider the complexity of transmission cycles and the interplay between domestic and sylvatic populations of mammals and vectors.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"54 11","pages":"Pages 559-568"},"PeriodicalIF":3.7,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0020751924001073/pdfft?md5=96a3bbd4f11f3639150ed3d465355083&pid=1-s2.0-S0020751924001073-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140957274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Challenging the phylogenetic relationships among Echinococcus multilocularis isolates from main endemic areas 挑战主要流行区多棘球蚴分离株之间的系统发育关系。
IF 3.7 2区 医学 Q1 PARASITOLOGY Pub Date : 2024-09-01 DOI: 10.1016/j.ijpara.2024.05.004

Alveolar echinococcosis (AE) is a rare but severe disease that affects more than 18,000 people worldwide per year. The complete sequencing of the mitochondrial genome of Echinococcus multilocularis has made it possible to study the genetic diversity of the parasite and its spatial and temporal evolution. We amplified the whole mitochondrial genome by PCR, using one uniplex and two multiplex reactions to cover the 13,738 bp of the mitogenome, and then sequenced the amplicons with Illumina technology. In total, 113 samples from Europe, Asia, the Arctic and North America were analyzed. Three major haplogroups were found: HG1, which clustered samples from Alaska (including Saint-Lawrence Island), Yakutia (Russia) and Svalbard; HG2, with samples from Asia, North America and Europe; and HG3, subdivided into three micro-haplogroups. HG3a included samples from North America and Europe, whereas HG3b and HG3c only include samples from Europe. In France, HG3a included samples from patients more recently diagnosed in a region outside the historical endemic area. A fourth putative haplogroup, HG4, was represented by only one isolate from Olkhon Island (Russia). The increased discriminatory power of the complete sequencing of the E. multilocularis mitogenome has made it possible to highlight four distinct geographical clusters, one being divided into three micro-haplogroups in France.

肺泡棘球蚴病(AE)是一种罕见但严重的疾病,全世界每年有 18,000 多人患病。对多棘球蚴线粒体基因组的完整测序使得研究这种寄生虫的遗传多样性及其时空演变成为可能。我们通过 PCR 扩增了整个线粒体基因组,使用了一个单工反应和两个多工反应来覆盖有丝分裂基因组的 13,738 bp,然后利用 Illumina 技术对扩增子进行了测序。共分析了来自欧洲、亚洲、北极和北美洲的 113 个样本。结果发现了三个主要的单倍群:HG1 聚集了来自阿拉斯加(包括圣劳伦斯岛)、雅库特(俄罗斯)和斯瓦尔巴群岛的样本;HG2 聚集了来自亚洲、北美和欧洲的样本;HG3 则细分为三个微型单倍群。HG3a 包括北美和欧洲的样本,而 HG3b 和 HG3c 只包括欧洲的样本。在法国,HG3a 包括最近在历史流行区以外地区确诊的患者样本。第四个可能的单倍群 HG4 仅有一个来自俄罗斯奥尔洪岛的分离株。多角体细胞有丝分裂基因组的完整测序提高了判别能力,从而突出了四个不同的地理集群,其中一个在法国被分为三个微单倍群。
{"title":"Challenging the phylogenetic relationships among Echinococcus multilocularis isolates from main endemic areas","authors":"","doi":"10.1016/j.ijpara.2024.05.004","DOIUrl":"10.1016/j.ijpara.2024.05.004","url":null,"abstract":"<div><p>Alveolar echinococcosis (AE) is a rare but severe disease that affects more than 18,000 people worldwide per year. The complete sequencing of the mitochondrial genome of <em>Echinococcus multilocularis</em> has made it possible to study the genetic diversity of the parasite and its spatial and temporal evolution. We amplified the whole mitochondrial genome by PCR, using one uniplex and two multiplex reactions to cover the 13,738 bp of the mitogenome, and then sequenced the amplicons with Illumina technology. In total, 113 samples from Europe, Asia, the Arctic and North America were analyzed. Three major haplogroups were found: HG1, which clustered samples from Alaska (including Saint-Lawrence Island), Yakutia (Russia) and Svalbard; HG2, with samples from Asia, North America and Europe; and HG3, subdivided into three micro-haplogroups. HG3a included samples from North America and Europe, whereas HG3b and HG3c only include samples from Europe. In France, HG3a included samples from patients more recently diagnosed in a region outside the historical endemic area. A fourth putative haplogroup, HG4, was represented by only one isolate from Olkhon Island (Russia). The increased discriminatory power of the complete sequencing of the <em>E. multilocularis</em> mitogenome has made it possible to highlight four distinct geographical clusters, one being divided into three micro-haplogroups in France.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"54 11","pages":"Pages 569-582"},"PeriodicalIF":3.7,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0020751924001103/pdfft?md5=c44d4ca1242fced2990e0efdff091bef&pid=1-s2.0-S0020751924001103-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141179468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Ghosts of parasites past influence current non-consumptive effects in Drosophila nigrospiracula 过去寄生虫的幽灵影响黑腹果蝇当前的非消耗性效应
IF 3.7 2区 医学 Q1 PARASITOLOGY Pub Date : 2024-09-01 DOI: 10.1016/j.ijpara.2024.04.008

Parasites can indirectly impact hosts through non-consumptive effects (NCEs) via changes in behaviour, morphology, and/or physiology. These responses can be understood in terms of the ecology of fear (ectoparasites) or the ecology of disgust (endoparasites) framework. We tested the hypothesis that NCEs of parasite exposure (e.g., parasite avoidance and defense) trade off with other important behaviours such as feeding and resting. We predicted that when exposed to parasites (without infection), hosts will increase their defensive behaviors at the expense of feeding. We also posited that history of exposure (without infection), or previous infection would impact the expression of these NCEs. The study system involves a cactophilic fruit fly (Drosophila nigrospiracula) and a naturally occurring parasitic mite (Macrocheles subbadius). First, we assessed how prior mite exposure affected fly behaviour in response to current parasite exposure. Mite presence resulted in increased grooming and movement, but exposure history did not affect these behaviours. However, the interaction between previous and current exposure influenced host feeding and resting behaviours. We found that previously exposed flies increased feeding and decreased resting upon a secondary mite exposure. In a second experiment, we tested the role of infection history on current parasite exposure. Compared with naïve flies, previously infected flies were expected to increase defensive behaviours upon secondary exposure. Flies increased defensive and ambulatory behaviour in the presence of mites, and consequently less time was spent resting but feeding was unaffected. None of the behaviours measured were affected by previous infection status. In general, current parasite exposure resulted in NCEs. Moreover, our results showed that previous exposure (without infection) to parasites may have an even stronger effect upon secondary exposure than infection history. Our study highlights the importance of the ecology of fear and the role that exposure and infection history plays in generating NCEs of parasitism.

寄生虫可通过行为、形态和/或生理变化对宿主产生非消费性影响(NCE),从而间接影响宿主。这些反应可以从恐惧生态学(外寄生虫)或厌恶生态学(内寄生虫)的框架来理解。我们测试了一个假设,即暴露于寄生虫环境中的NCE(如躲避寄生虫和防御寄生虫)会与其他重要行为(如进食和休息)发生交换。我们预测,当暴露于寄生虫(未感染)时,宿主会增加防御行为而牺牲进食。我们还假设,接触寄生虫的历史(未感染)或之前的感染会影响这些 NCEs 的表达。研究系统涉及一种嗜仙人掌果蝇(Drosophila nigrospiracula)和一种自然发生的寄生螨(Macrocheles subbadius)。首先,我们评估了先前的螨虫接触如何影响苍蝇对当前寄生虫接触的行为反应。螨虫的存在增加了苍蝇的梳理和运动,但接触史并不影响这些行为。然而,先前和当前暴露之间的相互作用影响了宿主的摄食和休息行为。我们发现,之前接触过螨虫的苍蝇在第二次接触螨虫时会增加摄食,减少休息。在第二个实验中,我们测试了感染史对当前寄生虫暴露的影响。与天真苍蝇相比,之前感染过寄生虫的苍蝇在二次接触寄生虫时会增加防御行为。在有螨虫存在的情况下,苍蝇会增加防御和活动行为,因此休息时间减少,但进食不受影响。所测量的行为均不受先前感染状况的影响。总的来说,当前的寄生虫暴露会导致无行为能力。此外,我们的研究结果表明,以前接触寄生虫(未感染)对二次接触的影响可能比感染史更大。我们的研究凸显了恐惧生态学的重要性,以及暴露和感染史在产生寄生虫非传染性行为中的作用。
{"title":"Ghosts of parasites past influence current non-consumptive effects in Drosophila nigrospiracula","authors":"","doi":"10.1016/j.ijpara.2024.04.008","DOIUrl":"10.1016/j.ijpara.2024.04.008","url":null,"abstract":"<div><p>Parasites can indirectly impact hosts through non-consumptive effects (NCEs) via changes in behaviour, morphology, and/or physiology. These responses can be understood in terms of the ecology of fear (ectoparasites) or the ecology of disgust (endoparasites) framework. We tested the hypothesis that NCEs of parasite exposure (e.g., parasite avoidance and defense) trade off with other important behaviours such as feeding and resting. We predicted that when exposed to parasites (without infection), hosts will increase their defensive behaviors at the expense of feeding. We also posited that history of exposure (without infection), or previous infection would impact the expression of these NCEs. The study system involves a cactophilic fruit fly (<em>Drosophila nigrospiracula</em>) and a naturally occurring parasitic mite (<em>Macrocheles subbadius</em>). First, we assessed how prior mite exposure affected fly behaviour in response to current parasite exposure. Mite presence resulted in increased grooming and movement, but exposure history did not affect these behaviours. However, the interaction between previous and current exposure influenced host feeding and resting behaviours. We found that previously exposed flies increased feeding and decreased resting upon a secondary mite exposure. In a second experiment, we tested the role of infection history on current parasite exposure. Compared with naïve flies, previously infected flies were expected to increase defensive behaviours upon secondary exposure. Flies increased defensive and ambulatory behaviour in the presence of mites, and consequently less time was spent resting but feeding was unaffected. None of the behaviours measured were affected by previous infection status. In general, current parasite exposure resulted in NCEs. Moreover, our results showed that previous exposure (without infection) to parasites may have an even stronger effect upon secondary exposure than infection history. Our study highlights the importance of the ecology of fear and the role that exposure and infection history plays in generating NCEs of parasitism.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"54 11","pages":"Pages 551-558"},"PeriodicalIF":3.7,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S002075192400078X/pdfft?md5=071607e5ac2bf5976c8f7eeb0ce9c541&pid=1-s2.0-S002075192400078X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140793131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Multiple UDP glycosyltransferases modulate benzimidazole drug sensitivity in the nematode Caenorhabditis elegans in an additive manner 多种 UDP 糖基转移酶以相加的方式调节线虫秀丽隐杆线虫对苯并咪唑类药物的敏感性
IF 3.7 2区 医学 Q1 PARASITOLOGY Pub Date : 2024-09-01 DOI: 10.1016/j.ijpara.2024.05.003

Xenobiotic biotransformation is an important modulator of anthelmintic drug potency and a potential mechanism of anthelmintic resistance. Both the free-living nematode Caenorhabditis elegans and the ruminant parasite Haemonchus contortus biotransform benzimidazole drugs by glucose conjugation, likely catalysed by UDP-glycosyltransferase (UGT) enzymes. To identify C. elegans genes involved in benzimidazole drug detoxification, we first used a comparative phylogenetic analysis of UGTs from humans, C. elegans and H. contortus, combined with available RNAseq datasets to identify which of the 63 C. elegans ugt genes are most likely to be involved in benzimidazole drug biotransformation. RNA interference knockdown of 15 prioritized C. elegans genes identified those that sensitized animals to the benzimidazole derivative albendazole (ABZ). Genetic mutations subsequently revealed that loss of ugt-9 and ugt-11 had the strongest effects. The “ugt-9 cluster” includes these genes, together with six other closely related ugts. A CRISPR-Cas-9 deletion that removed seven of the eight ugt-9 cluster genes had greater ABZ sensitivity than the single largest-effect mutation. Furthermore, a double mutant of ugt-22 (which is not a member of the ugt-9 cluster) with the ugt-9 cluster deletion further increased ABZ sensitivity. This additivity of mutant phenotypes suggest that ugt genes act in parallel, which could have several, not mutually exclusive, explanations. ugt mutations have different effects with different benzimidazole derivatives, suggesting that enzymes with different specificities could together more efficiently detoxify drugs. Expression patterns of ugt-9, ugt-11 and ugt-22 gfp reporters differ and so likely act in different tissues which may, at least in part, explain their additive effects on drug potency. Overexpression of ugt-9 alone was sufficient to confer partial ABZ resistance, indicating increasing total UGT activity protects animals. In summary, our results suggest that the multiple UGT enzymes have overlapping but not completely redundant functions in benzimidazole drug detoxification and may represent “druggable” targets to improve benzimidazole drug potency.

异生物的生物转化是抗蠕虫药药效的重要调节因素,也是产生抗蠕虫药耐药性的潜在机制。自由生活的线虫秀丽隐杆线虫(Caenorhabditis elegans)和反刍动物寄生虫柯氏血吸虫(Haemonchus contortus)都通过葡萄糖共轭作用对苯并咪唑类药物进行生物转化,这种作用可能是由 UDP-糖基转移酶(UGT)催化的。为了确定参与苯并咪唑类药物解毒的秀丽隐杆线虫基因,我们首先对来自人类、秀丽隐杆线虫和H. contortus的UGT进行了系统发育比较分析,并结合现有的RNAseq数据集,确定了63个秀丽隐杆线虫ugt基因中哪些基因最有可能参与苯并咪唑类药物的生物转化。通过 RNA 干扰敲除 15 个优先考虑的秀丽隐杆线虫基因,确定了那些能使动物对苯并咪唑衍生物阿苯达唑(ABZ)过敏的基因。随后的基因突变显示,ugt-9 和 ugt-11 基因的缺失影响最大。ugt-9基因簇 "包括这些基因以及其他六个密切相关的ugts基因。通过 CRISPR-Cas-9 基因缺失,去除了 8 个 ugt-9 簇基因中的 7 个,其对 ABZ 的敏感性要高于单一的最大效应突变。此外,ugt-22(不属于 ugt-9 基因簇)与 ugt-9 基因簇缺失的双突变体进一步提高了 ABZ 的敏感性。ugt突变对不同的苯并咪唑衍生物有不同的影响,这表明具有不同特异性的酶可以共同更有效地解毒。ugt-9、ugt-11 和 ugt-22 gfp 报告基因的表达模式不同,因此可能作用于不同的组织,这至少可以部分解释它们对药物效力的叠加效应。单独过表达 ugt-9 就足以产生部分 ABZ 抗性,这表明保护动物的总 UGT 活性在增加。总之,我们的研究结果表明,多种 UGT 酶在苯并咪唑类药物解毒过程中具有重叠但非完全冗余的功能,可能是提高苯并咪唑类药物药效的 "可药物 "靶点。
{"title":"Multiple UDP glycosyltransferases modulate benzimidazole drug sensitivity in the nematode Caenorhabditis elegans in an additive manner","authors":"","doi":"10.1016/j.ijpara.2024.05.003","DOIUrl":"10.1016/j.ijpara.2024.05.003","url":null,"abstract":"<div><p>Xenobiotic biotransformation is an important modulator of anthelmintic drug potency and a potential mechanism of anthelmintic resistance. Both the free-living nematode <em>Caenorhabditis elegans</em> and the ruminant parasite <em>Haemonchus contortus</em> biotransform benzimidazole drugs by glucose conjugation, likely catalysed by UDP-glycosyltransferase (UGT) enzymes. To identify <em>C. elegans</em> genes involved in benzimidazole drug detoxification, we first used a comparative phylogenetic analysis of UGTs from humans<em>, C. elegans</em> and <em>H. contortus,</em> combined with available RNAseq datasets to identify which of the 63 <em>C. elegans ugt</em> genes are most likely to be involved in benzimidazole drug biotransformation<em>.</em> RNA interference knockdown of 15 prioritized <em>C. elegans</em> genes identified those that sensitized animals to the benzimidazole derivative albendazole (ABZ). Genetic mutations subsequently revealed that loss of <em>ugt-9</em> and <em>ugt-11</em> had the strongest effects. The “<em>ugt-9 cluster</em>” includes these genes, together with six other closely related <em>ugt</em>s. A CRISPR-Cas-9 deletion that removed seven of the eight <em>ugt-9 cluster</em> genes had greater ABZ sensitivity than the single largest-effect mutation. Furthermore, a double mutant of <em>ugt-22</em> (which is not a member of the <em>ugt-9 cluster)</em> with the <em>ugt-9 cluster</em> deletion further increased ABZ sensitivity. This additivity of mutant phenotypes suggest that <em>ugt</em> genes act in parallel, which could have several, not mutually exclusive, explanations. <em>ugt</em> mutations have different effects with different benzimidazole derivatives, suggesting that enzymes with different specificities could together more efficiently detoxify drugs. Expression patterns of <em>ugt-9, ugt-11</em> and <em>ugt-22 gfp</em> reporters differ and so likely act in different tissues which may, at least in part, explain their additive effects on drug potency. Overexpression of <em>ugt-9</em> alone was sufficient to confer partial ABZ resistance, indicating increasing total UGT activity protects animals. In summary, our results suggest that the multiple UGT enzymes have overlapping but not completely redundant functions in benzimidazole drug detoxification and may represent “druggable” targets to improve benzimidazole drug potency.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"54 11","pages":"Pages 535-549"},"PeriodicalIF":3.7,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0020751924001097/pdfft?md5=1b485fbd725694b19b4f5bc56ae0cd6f&pid=1-s2.0-S0020751924001097-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141161331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
GRA47 is important for the morphology and permeability of the parasitophorous vacuole in Toxoplasma gondii GRA47 对弓形虫寄生泡的形态和渗透性非常重要。
IF 3.7 2区 医学 Q1 PARASITOLOGY Pub Date : 2024-09-01 DOI: 10.1016/j.ijpara.2024.06.003

Establishing an intact intracellular parasitophorous vacuole (PV) that enables efficient nutrient uptake and protein trafficking is essential for the survival and proliferation of Toxoplasma gondii. Although the PV membrane (PVM)-localized dense granule protein 17 (GRA17) and GRA23 mediate the permeability of the PVM to small molecules, including nutrient uptake and excretion of metabolic by-products, the molecular mechanism by which T. gondii acquires nutrients remains unclear. In this study, we showed that the secreted protein GRA47 contributed to normal PV morphology, PVM permeability to small molecules, growth, and virulence in T. gondii. Co-immunoprecipitation analysis demonstrated potential interaction of GRA47 with GRA72, and the loss of GRA72 affected PV morphology, parasite growth and infectivity. To investigate the biological relationship among GRA47, GRA72, GRA17 and GRA23, attempts were made to construct strains with double gene deletion and overexpressing strains. Only Δgra23Δgra72 was successfully constructed. This strain exhibited a significant increase in the proportion of aberrant PVs compared with the Δgra23 strain. Overexpressing one of the three related GRAs partially rescued PVs with aberrant morphology in Δgra47, Δgra72 and Δgra17, while the expression of the Plasmodium falciparum PVM protein PfExp2, an ortholog of GRA17 and GRA23, fully rescued the PV morphological defect in all three Δgra strains. These results suggest that these GRA proteins may not be functionally redundant but rather work in different ways to regulate nutrient acquisition. These findings highlight the versatility of the nutrient uptake mechanisms in T. gondii, which may contribute to the parasite’s remarkable ability to grow in different cellular niches in a very broad range of hosts.

建立一个完整的细胞内寄生虫液泡(PV),使其能够有效地摄取营养物质和贩运蛋白质,对于弓形虫的生存和增殖至关重要。虽然PV膜(PVM)定位的致密颗粒蛋白17(GRA17)和GRA23介导了PVM对小分子的通透性,包括营养物质的摄取和代谢副产物的排泄,但弓形虫获取营养物质的分子机制仍不清楚。在这项研究中,我们发现分泌蛋白 GRA47 对淋病双球菌正常的 PV 形态、PVM 对小分子的通透性、生长和毒力都有贡献。共免疫沉淀分析表明 GRA47 与 GRA72 有潜在的相互作用,而 GRA72 的缺失会影响 PV 形态、寄生虫的生长和感染性。为了研究 GRA47、GRA72、GRA17 和 GRA23 之间的生物学关系,尝试构建了双基因缺失株和过表达株。结果只成功构建了Δgra23Δgra72。与 Δgra23 株系相比,该株系的异常 PV 比例明显增加。过表达三个相关 GRA 中的一个可部分修复 Δgra47、Δgra72 和 Δgra17 中形态异常的 PV,而表达恶性疟原虫 PVM 蛋白 PfExp2(GRA17 和 GRA23 的直系同源物)可完全修复所有三个 Δgra 株系中的 PV 形态缺陷。这些结果表明,这三种 GRA 蛋白可能并非功能冗余,而是以不同的方式调节营养物质的获取。这些发现凸显了淋球菌营养摄取机制的多样性,这可能是淋球菌能够在多种宿主的不同细胞环境中生长的重要原因。
{"title":"GRA47 is important for the morphology and permeability of the parasitophorous vacuole in Toxoplasma gondii","authors":"","doi":"10.1016/j.ijpara.2024.06.003","DOIUrl":"10.1016/j.ijpara.2024.06.003","url":null,"abstract":"<div><p>Establishing an intact intracellular parasitophorous vacuole (PV) that enables efficient nutrient uptake and protein trafficking is essential for the survival and proliferation of <span><em>Toxoplasma gondii</em></span><span>. Although the PV membrane (PVM)-localized dense granule protein 17 (GRA17) and GRA23 mediate the permeability of the PVM to small molecules, including nutrient uptake and excretion of metabolic by-products, the molecular mechanism by which </span><em>T. gondii</em> acquires nutrients remains unclear. In this study, we showed that the secreted protein GRA47 contributed to normal PV morphology, PVM permeability to small molecules, growth, and virulence in <em>T. gondii</em>. Co-immunoprecipitation analysis demonstrated potential interaction of GRA47 with GRA72, and the loss of GRA72 affected PV morphology, parasite growth and infectivity. To investigate the biological relationship among GRA47, GRA72, GRA17 and GRA23, attempts were made to construct strains with double gene deletion and overexpressing strains. Only Δ<em>gra</em>23Δ<em>gra72</em> was successfully constructed. This strain exhibited a significant increase in the proportion of aberrant PVs compared with the Δ<em>gra23</em> strain. Overexpressing one of the three related GRAs partially rescued PVs with aberrant morphology in Δ<em>gra47</em>, Δ<em>gra72</em> and Δ<em>gra17</em>, while the expression of the <em>Plasmodium falciparum</em> PVM protein <em>Pf</em>Exp2, an ortholog of GRA17 and GRA23, fully rescued the PV morphological defect in all three Δ<em>gra</em> strains. These results suggest that these GRA proteins may not be functionally redundant but rather work in different ways to regulate nutrient acquisition. These findings highlight the versatility of the nutrient uptake mechanisms in <em>T. gondii</em>, which may contribute to the parasite’s remarkable ability to grow in different cellular niches in a very broad range of hosts.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"54 11","pages":"Pages 583-596"},"PeriodicalIF":3.7,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141467798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
What shapes a microbiome? Differences in bacterial communities associated with helminth-amphipod interactions. 是什么塑造了微生物群落?与蠕虫-片脚类动物相互作用相关的细菌群落差异
IF 3.7 2区 医学 Q1 PARASITOLOGY Pub Date : 2024-08-30 DOI: 10.1016/j.ijpara.2024.08.005
Célia Koellsch, Robert Poulin, Priscila M Salloum

The fast technological advances of molecular tools have enabled us to uncover a new dimension hidden within parasites and their hosts: their microbiomes. Increasingly, parasitologists characterise host microbiome changes in the face of parasitic infections, revealing the potential of these microscopic fast-evolving entities to influence host-parasite interactions. However, most of the changes in host microbiomes seem to depend on the host and parasite species in question. Furthermore, we should understand the relative role of parasitic infections as microbiome modulators when compared with other microbiome-impacting factors (e.g., host size, age, sex). Here, we characterised the microbiome of a single intermediate host species infected by two parasites belonging to different phyla: the acanthocephalan Plagiorhynchus allisonae and a dilepidid cestode, both infecting Transorchestia serrulata amphipods collected simultaneously from the same locality. We used the v4 hypervariable region of the 16S rRNA prokaryotic gene to identify the hemolymph bacterial community of uninfected, acanthocephalan-infected, and cestode-infected amphipods, as well as the bacteria in the amphipods' immediate environment and in the parasites infecting them. Our results show that parasitic infections were more strongly associated with differences in host bacterial community richness than amphipod size, presence of amphipod eggs in female amphipods, and even parasite load. Amphipods infected by acanthocephalans had the most divergent bacterial community, with a marked decrease in alpha diversity compared with cestode-infected and uninfected hosts. In accordance with the species-specific nature of microbiome changes in parasitic infections, we found unique microbial taxa associating with hosts infected by each parasite species, as well as taxa only shared between a parasite species and their infected hosts. However, there were some bacterial taxa detected in all parasitised amphipods (regardless of the parasite species), but not in uninfected amphipods or the environment. We propose that shared bacteria associated with all hosts parasitised by distantly related helminths may be important either in helping host defences or parasites' success, and could thus interact with host-parasite evolution.

分子工具技术的飞速发展使我们能够发现隐藏在寄生虫及其宿主体内的一个新维度:寄生虫微生物组。越来越多的寄生虫学家描述了寄生虫感染时宿主微生物组的变化,揭示了这些快速进化的微观实体影响宿主-寄生虫相互作用的潜力。然而,宿主微生物组的大多数变化似乎取决于宿主和寄生虫的种类。此外,与其他影响微生物组的因素(如宿主大小、年龄、性别)相比,我们应该了解寄生虫感染作为微生物组调节剂的相对作用。在这里,我们描述了被属于不同门类的两种寄生虫感染的单一中间宿主的微生物组特征:棘头蚤(Plagiorhynchus allisonae)和双尾蚤(dilepidid cestode),这两种寄生虫都感染了从同一地点同时采集的Transorchestia serrulata片脚类动物。我们利用 16S rRNA 原核基因的 v4 超变区鉴定了未感染、感染棘头蚴和感染绦虫的片脚类动物的血淋巴细菌群落,以及片脚类动物周围环境和感染片脚类动物的寄生虫中的细菌。我们的研究结果表明,寄生虫感染与寄主细菌群落丰富度的差异有更密切的关系,而与片脚类动物的大小、雌性片脚类动物体内片脚类动物卵的存在,甚至寄生虫量的差异都没有关系。被棘尾虫感染的片脚类动物的细菌群落差异最大,与绦虫感染和未感染的宿主相比,α多样性明显下降。根据寄生虫感染时微生物群落变化的物种特异性,我们发现了与每种寄生虫感染的宿主相关的独特微生物类群,以及仅在寄生虫物种和感染宿主之间共享的类群。然而,在所有被寄生的片脚类动物(无论寄生虫种类)中都检测到了一些细菌类群,但在未感染的片脚类动物或环境中却没有检测到。我们认为,与所有被远缘蠕虫寄生的宿主相关的共有细菌可能在帮助宿主防御或寄生虫成功寄生方面具有重要作用,因此可能与宿主-寄生虫的进化相互影响。
{"title":"What shapes a microbiome? Differences in bacterial communities associated with helminth-amphipod interactions.","authors":"Célia Koellsch, Robert Poulin, Priscila M Salloum","doi":"10.1016/j.ijpara.2024.08.005","DOIUrl":"10.1016/j.ijpara.2024.08.005","url":null,"abstract":"<p><p>The fast technological advances of molecular tools have enabled us to uncover a new dimension hidden within parasites and their hosts: their microbiomes. Increasingly, parasitologists characterise host microbiome changes in the face of parasitic infections, revealing the potential of these microscopic fast-evolving entities to influence host-parasite interactions. However, most of the changes in host microbiomes seem to depend on the host and parasite species in question. Furthermore, we should understand the relative role of parasitic infections as microbiome modulators when compared with other microbiome-impacting factors (e.g., host size, age, sex). Here, we characterised the microbiome of a single intermediate host species infected by two parasites belonging to different phyla: the acanthocephalan Plagiorhynchus allisonae and a dilepidid cestode, both infecting Transorchestia serrulata amphipods collected simultaneously from the same locality. We used the v4 hypervariable region of the 16S rRNA prokaryotic gene to identify the hemolymph bacterial community of uninfected, acanthocephalan-infected, and cestode-infected amphipods, as well as the bacteria in the amphipods' immediate environment and in the parasites infecting them. Our results show that parasitic infections were more strongly associated with differences in host bacterial community richness than amphipod size, presence of amphipod eggs in female amphipods, and even parasite load. Amphipods infected by acanthocephalans had the most divergent bacterial community, with a marked decrease in alpha diversity compared with cestode-infected and uninfected hosts. In accordance with the species-specific nature of microbiome changes in parasitic infections, we found unique microbial taxa associating with hosts infected by each parasite species, as well as taxa only shared between a parasite species and their infected hosts. However, there were some bacterial taxa detected in all parasitised amphipods (regardless of the parasite species), but not in uninfected amphipods or the environment. We propose that shared bacteria associated with all hosts parasitised by distantly related helminths may be important either in helping host defences or parasites' success, and could thus interact with host-parasite evolution.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142107086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
International journal for parasitology
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1