| the susceptibility of three species in three genera of mosquito larvae to a microsporidian vavraia culicis (weiser) and its histopathology on the tissues of the recipient host anopheles gambiae giles in the laboratory. | | 1986 | 3110060 |
| parasites of the asian tiger mosquito and other container-inhabiting mosquitoes (diptera:culicidae) in northcentral florida. | seven microorganisms including 4 protozoans, 2 fungi, and a bacterium infected aedes albopictus (skuse) larvae collected from 12 counties in northecentral florida. ae albopictus and 14 other species of mosquitoes were collected from tires, flower-holding vases in cemeteries, other types of artificial containers, and treeholes. ascogregarina taiwanensis (lien & levine) was the most common parasite of ae. albopictus throughout the year. the microsporidium vavraia culicis (weiser) infected aedes ae ... | 1997 | 9103767 |
| microsporidian intrasporal sugars and their role in germination. | the hypothesis that spores of terrestrial and aquatic microsporidia differ in their utilization of sugars was tested by evaluating the sugars in germinated and ungerminated spores of several species in each category. the aquatic species tested were vavraia culicis, edhazardia aedis, and nosema algerae and the terrestrial species were vairimorpha necatrix, nosema disstriae, nosema apis, vairimorpha lymantriae, and nosema spp. from spodoptera exigua and plutella xylostella. the percentage germinat ... | 1999 | 10222184 |
| phylogenetic relationships of pleistophora-like microsporidia based on small subunit ribosomal dna sequences and implications for the source of trachipleistophora hominis infections. | the microsporidian trachipleistophora hominis was isolated in vitro from the skeletal muscle of an aids patient. since its discovery several more cases of myositis due to trachipleistophora have been diagnosed but the source of infection is unknown. morphologically, t. hominis most closely resembles pleistophora and vavraia, which undergo polysporous sporogony in sporophorous vesicles, but differs from these genera in the mode of formation of sporoblasts and in the morphology of the sporophorous ... | 2000 | 10847345 |
| relationships of microsporidian genera, with emphasis on the polysporous genera, revealed by sequences of the largest subunit of rna polymerase ii (rpb1). | molecular data have proved useful as an alternative to morphological data in showing the relationships of genera within the phylum microsporidia, but until now have been available only for ribosomal genes. in previous studies protein-coding genes of microsporidia have been used only to assess their position in the evolution of eukaryotes. for the first time we report on the use of a protein-coding gene, the a-g region of the largest subunit of rna polymerase ii (rpb1) from 14 mainly polysporous ... | 2001 | 11249186 |
| serological differentiation of microsporidia with special reference to trachipleistophora hominis. | myositis is a common clinical syndrome in advanced stages of aids. trachipleistophora hominis (phylum microspora) has been detected in several cases of painful, immobilising myositis in aids patients. enzyme linked immunosorbent assays (elisas) and western blotting of protein profiles separated by sds page were used to determine whether this species could be detected and differentiated by serology. sixteen microsporidia, including several species known to infect man and species infecting fish, c ... | 2001 | 11474986 |
| virulence reaction norms across a food gradient. | host-parasite interactions involve competition for nutritional resources between hosts and the parasites growing within them. consuming part of a host's resources is one cause of a parasite's virulence, i.e. part of the fitness cost imposed on the host by the parasite. the influence of a host's nutritional conditions on the virulence of a parasite was experimentally tested using the mosquito aedes aegypti and the microsporidian parasite vavraia culicis. a condition-dependent expression of virule ... | 2004 | 15209108 |
| review of microsporidia-mosquito relationships: from the simple to the complex. | microsporidia in mosquitoes can be divided into two categories based on their life cycles and host-parasite relationships. some species of microsporidia exhibit simple life cycles with one spore type responsible for oral (horizontal) transmission. they affect only one generation of the mosquito and are not usually host or tissue specific. brachiola algerae and vavraia culicis are examples of species isolated from mosquitoes with relatively straightforward life cycles (one spore type) and simple ... | 2005 | 16004363 |
| a possible mechanism for the suppression of plasmodium berghei development in the mosquito anopheles gambiae by the microsporidian vavraia culicis. | microsporidian parasites of mosquitoes offer a possible way of controlling malaria, as they impede the development of plasmodium parasites within the mosquito. the mechanism involved in this interference process is unknown. | 2009 | 19277119 |
| opportunistic nature of the mammalian microsporidia: experimental transmission of trachipleistophora extenrec (fungi: microsporidia) between mammalian and insect hosts. | spores of trachipleistophora extenrec, originally isolated from the muscles of the madagascan insectivore hemicentetes semispinosus and maintained by serial passage in severe combined immunodeficiency (scid) mice, were fed to larvae of the egyptian cotton leafworm spodoptera littoralis. extensive infection of larval tissues ensued and caused larval and pupal mortality. the development of t. extenrec in the insect host, studied both by light and electron microscopy, followed generally the same li ... | 2010 | 21188601 |
| maternal environment shapes the life history and susceptibility to malaria of anopheles gambiae mosquitoes. | abstract: background: it is becoming generally recognized that an individual's phenotype can be shaped not only by its own genotype and environmental experience, but also by its mother's environment and condition. maternal environmental factors can influence mosquitoes' population dynamics and susceptibility to malaria, and therefore directly and indirectly the epidemiology of malaria. methods: in a full factorial experiment, the effects of two environmental stressors - food availability and i ... | 2011 | 22188602 |
| contrasting host-pathogen interactions and genome evolution in two generalist and specialist microsporidian pathogens of mosquitoes. | obligate intracellular pathogens depend on their host for growth yet must also evade detection by host defenses. here we investigate host adaptation in two microsporidia, the specialist edhazardia aedis and the generalist vavraia culicis, pathogens of disease vector mosquitoes. genomic analysis and deep rna-seq across infection time courses reveal fundamental differences between these pathogens. e. aedis retains enhanced cell surface modification and signalling capacity, upregulating protein tra ... | 2015 | 25968466 |
| prevalence-dependent costs of parasite virulence. | costs of parasitism are commonly measured by comparing the performance of infected groups of individuals to that of uninfected control groups. this measure potentially underestimates the cost of parasitism because it ignores indirect costs, which may result from the modification of the competitiveness of the hosts by the parasite. in this context, we used the host-parasite system consisting of the yellow fever mosquito aedes aegypti and the microsporidian parasite vavraia culicis to address this ... | 2005 | 16008503 |
| reduced survival and reproductive success generates selection pressure for the dengue mosquito aedes aegypti to evolve resistance against infection by the microsporidian parasite vavraia culicis. | the success and sustainability of control measures aimed at reducing the transmission of mosquito-borne diseases will depend on how they influence the fitness of mosquitoes in targeted populations. we investigated the effects of the microsporidian parasite vavraia culicis on the survival, blood-feeding behaviour and reproductive success of female aedes aegypti mosquitoes, the main vector of dengue. infection reduced survival to adulthood and increased adult female mosquito age-dependent mortalit ... | 2014 | 24822081 |
| virulence and resistance in a mosquito-microsporidium interaction. | we review the results of a series of experiments involving aedes aegypti and its microsporidian parasite vavraia culicis to illustrate how intra-specific competition and parasitism shape life history traits. more specifically these experiments showed that some major components of virulence are host condition-dependent in this system, while others are not. we also briefly discuss the ways through which v. culicis modifies the physiological functioning of its host. we discuss the implications of t ... | 0 | 25567490 |
| genome analysis and polar tube firing dynamics of mosquito-infecting microsporidia. | microsporidia are highly divergent fungi that are obligate intracellular pathogens of a wide range of host organisms. here we review recent findings from the genome sequences of mosquito-infecting microsporidian species edhazardia aedis and vavraia culicis, which show large differences in genome size, although similar numbers of predicted genes. we also show a video of e. aedis polar tube firing, which is the dramatic mechanism used by microsporidia to deliver the germ cell (sporoplasm) into the ... | 2015 | 26300319 |
| proteome of aedes aegypti in response to infection and coinfection with microsporidian parasites. | hosts are frequently infected with more than one parasite or pathogen at any one time, but little is known as to how they respond to multiple immune challenges compared to those involving single infections. we investigated the proteome of aedes aegypti larvae following infection with either edhazardia aedis or vavraia culicis, and coinfections involving both. they are both obligate intracellular parasites belonging to the phylum microsporidia and infect natural populations of ae. aegypti. the re ... | 0 | 22837817 |
| the microsporidian parasite vavraia culicis as a potential late life-acting control agent of malaria. | microsporidian parasites are being considered as alternatives to conventional insecticides for malaria control. they should reduce malaria transmission by shortening the lifespan of female mosquitoes and thus killing them before they transmit malaria. as the parasite replicates throughout the mosquito's life, it should have little detrimental effects on young mosquitoes, thus putting less selection pressure on the hosts to evolve resistance. here, we examined these expectations for the microspor ... | 2011 | 25568022 |
| blocking the evolution of insecticide-resistant malaria vectors with a microsporidian. | finding a way to block the evolution insecticide resistance would be a major breakthrough for the control of malaria. we suggest that this may be possible by introducing a stress into mosquito populations that restores the sensitivity of genetically resistant mosquitoes and that decreases their longevity when they are not exposed to insecticide. we use a mathematical model to show that, despite the intense selection pressure imposed by insecticides, moderate levels of stress might tip the evolut ... | 2011 | 25568048 |
| the consequences of co-infections for parasite transmission in the mosquito aedes aegypti. | co-infections may modify parasite transmission opportunities directly as a consequence of interactions in the within-host environment, but also indirectly through changes in host life history. furthermore, host and parasite traits are sensitive to the abiotic environment with variable consequences for parasite transmission in co-infections. we investigate how co-infection of the mosquito aedes aegypti with two microsporidian parasites (vavraia culicis and edhazardia aedis) at two levels of larva ... | 2015 | 25311642 |
| oviposition substrate selection by florida mosquitoes in response to pathogen-infected conspecific larvae. | the impact of the presence of larval mosquito pathogens with potential for biological control on oviposition choice was evaluated for three mosquito species/pathogen pairs present in florida. these included aedes aegypti infected with edhazardia aedis, aedes albopictus infected with vavraia culicis, and culex quinquefasciatus infected with culex nigripalpus nucleopolyhedrovirus (cuninpv). two-choice oviposition bioassays were performed on each host and pathogen species with one oviposition cup c ... | 2013 | 23701624 |
| comparative analysis of the proteins with tandem repeats from 8 microsporidia and characterization of a novel endospore wall protein colocalizing with polar tube from nosema bombycis. | as a common feature of eukaryotic proteins, tandem amino acid repeat has been studied extensively in both animal and plant proteins. here, a comparative analysis focusing on the proteins having tandem repeats was conducted in 8 microsporidia, including four mammal-infecting microsporidia (encephalitozoon cuniculi, encephalitozoon intestinalis, encephalitozoon hellem and encephalitozoon bieneusi) and four insect-infecting microsporidia (nosema apis, nosema ceranae, vavraia culicis and nosema bomb ... | 2017 | 28321967 |
| cost of co-infection controlled by infectious dose combinations and food availability. | to what extent the combined effect of several parasite species co-infecting the same host (i.e. polyparasitism) affects the host's fitness is a crucial question of ecological parasitology. we investigated whether the ecological setting can influence the co-infection's outcome with the mosquito aedes aegypti and two parasites: the microsporidium vavraia culicis and the gregarine ascogregarina culicis. the cost of being infected by the two parasites depended on the interaction between the two infe ... | 2010 | 20033214 |
| infectious dose affects the outcome of the within-host competition between parasites. | the ecological and epidemiological processes underlying the success of parasites competing within individual hosts are not yet clear. we investigated one idea: that increasing one parasite's infectious dose might decrease the success of its competitor. we reared uninfected larvae of the mosquito aedes aegypti and exposed them to two concentrations of the microsporidium vavraia culicis and of the protozoan ascogregarina culicis. the rate at which vavraia produced its infectious spores depended on ... | 2009 | 19320595 |
| vavraia culicis (weiser, 1947) weiser, 1977 revisited: cytological characterisation of a vavraia culicis-like microsporidium isolated from mosquitoes in florida and the establishment of vavraia culicis floridensis subsp. n. | a brief nomenclatural history of vavraia culicis (weiser, 1947), the type species for the genus vavraia weiser, 1977, is presented together with a detailed description of the cytological and ultrastructural characteristics of a vavraia culicis-like microsporidian species isolated from aedes albopictus (scuse) in florida. this "florida isolate", is the only known isolate of a species of the genus vavraia from mosquitoes propagated in laboratory culture. although the florida isolate has been used ... | 2007 | 18303767 |
| resource depletion in aedes aegypti mosquitoes infected by the microsporidia vavraia culicis. | summaryparasitic infection is often associated with changes in host life-history traits, such as host development. many of these life-history changes are ultimately thought to be the result of a depletion or reallocation of the host's resources driven either by the host (to minimize the effects of infection) or by the parasite (to maximize its growth rate). in this paper we investigate the energetic budget of aedes aegypti mosquito larvae infected by vavraia culicis, a microsporidian parasite th ... | 2007 | 17634157 |
| characterization of a pathogen related to vavraia culicis detected in a laboratory colony of anopheles stephensi. | | 2006 | 17169070 |
| proteome of aedes aegypti larvae in response to infection by the intracellular parasite vavraia culicis. | we report on the modification of the aedes aegypti larval proteome following infection by the microsporidian parasite vavraia culicis. mosquito larvae were sampled at 5 and 15 days of age to compare the effects of infection when the parasite was in two different developmental stages. modifications of the host proteome due to the stress of infection were distinguished from those of a more general nature by treatments involving hypoxia. we found that the major reaction to stress was the suppressio ... | 2005 | 16102770 |
| on the development cycle and ultrastructure of vavraia culicis weiser, 1947 (microsporida, pleistophoridae) with comments on the taxonomy of the genus vavraia weiser, 1977. | vavraia culicis was studied using light and electron microscopy. the hosts were larvae of anopheles gambiae collected in senegal. merogonial and sporogonial plasmodia had isolated nuclei. a thick amorphous coat was formed externally to the plasma membrane of the merogonial plasmodium, which developed into the envelope of the sporophorous vesicle. division of merogonial and sporogonial plasmodia occurred by plasmotomy. only one type of spores was produced. the polar filament was anisofilar. meios ... | 1991 | 23194705 |