| Assessing aphids potato virus Y-transmission efficiency: A new approach. | In order to develop an alternative method to optimize the relative efficiency factor (REF) assessment, the efficiency of transmission of Potato virus Y (PVY) by seven aphid species was examined. In vitro micropropagated potato plantlets were used to experiment on phenotypically and genetically homogeneous material. Species-specific acquisition access period (AAP) on a PVY-infected plantlet was assessed for each aphid species using electrical penetration graph (EPG) technique. Aphid probing behav ... | 2011 | 21884729 |
| mammalian herbivore breath alerts aphids to flee host plant. | mammalian herbivores profoundly influence plant-dwelling insects [1]. most studies have focused on the indirect effect of herbivory on insect populations via damage to the host plant [2,3]. many insects, however, are in danger of being inadvertently ingested during herbivore feeding. here, we report that pea aphids (acyrthosiphon pisum) are able to sense the elevated heat and humidity of the breath of an approaching herbivore and thus salvage most of the colony by simultaneously dropping off the ... | 2010 | 20692607 |
| dynamics of genome evolution in facultative symbionts of aphids. | aphids are sap-feeding insects that host a range of bacterial endosymbionts including the obligate, nutritional mutualist buchnera plus several bacteria that are not required for host survival. among the latter, 'candidatus regiella insecticola' and 'candidatus hamiltonella defensa' are found in pea aphids and other hosts and have been shown to protect aphids from natural enemies. we have sequenced almost the entire genome of r. insecticola (2.07 mbp) and compared it with the recently published ... | 2010 | 21966902 |
| aphid reproductive investment in response to mortality risks. | aphids are striking in their prodigious reproductive capacity and reliance on microbial endosymbionts, which provision their hosts with necessary amino acids and provide protection against parasites and heat stress. perhaps as a result of this bacterial dependence, aphids have limited immune function that may leave them vulnerable to bacterial pathogens. an alternative, non-immunological response that may be available to infected aphids is to increase reproduction, thereby ameliorating fitness l ... | 2010 | 20716370 |
| how the insect immune system interacts with an obligate symbiotic bacterium. | the animal immune system provides defence against microbial infection, and the evolution of certain animal-microbial symbioses is predicted to involve adaptive changes in the host immune system to accommodate the microbial partner. for example, the reduced humoral immune system in the pea aphid acyrthosiphon pisum, including an apparently non-functional immune deficiency (imd) signalling pathway and absence of peptidoglycan recognition proteins (pgrps), has been suggested to be an adaptation for ... | 2011 | 20719775 |
| effects of bacterial secondary symbionts on host plant use in pea aphids. | aphids possess several facultative bacterial symbionts that have important effects on their hosts' biology. these have been most closely studied in the pea aphid (acyrthosiphon pisum), a species that feeds on multiple host plants. whether secondary symbionts influence host plant utilization is unclear. we report the fitness consequences of introducing different strains of the symbiont hamiltonella defensa into three aphid clones collected on lathyrus pratensis that naturally lack symbionts, and ... | 2011 | 20843842 |
| identification of the main venom protein components of aphidius ervi, a parasitoid wasp of the aphid model acyrthosiphon pisum. | endoparasitoid wasps are important natural enemies of the widely distributed aphid pests and are mainly used as biological control agents. however, despite the increased interest on aphid interaction networks, only sparse information is available on the factors used by parasitoids to modulate the aphid physiology. our aim was here to identify the major protein components of the venom injected at oviposition by aphidius ervi to ensure successful development in its aphid host, acyrthosiphon pisum. | 2014 | 24884493 |
| horizontal transfer of bacterial symbionts: heritability and fitness effects in a novel aphid host. | members of several bacterial lineages are known only as symbionts of insects and move among hosts through maternal transmission. such vertical transfer promotes strong fidelity within these associations, favoring the evolution of microbially mediated effects that improve host fitness. however, phylogenetic evidence indicates occasional horizontal transfer among different insect species, suggesting that some microbial symbionts retain a generalized ability to infect multiple hosts. here we examin ... | 2005 | 16332777 |
| large-scale gene discovery in the pea aphid acyrthosiphon pisum (hemiptera). | aphids are the leading pests in agricultural crops. a large-scale sequencing of 40,904 ests from the pea aphid acyrthosiphon pisum was carried out to define a catalog of 12,082 unique transcripts. a strong at bias was found, indicating a compositional shift between drosophila melanogaster and a. pisum. an in silico profiling analysis characterized 135 transcripts specific to pea-aphid tissues (relating to bacteriocytes and parthenogenetic embryos). this project is the first to address the geneti ... | 2006 | 16542494 |
| lateral gene transfer between prokaryotes and multicellular eukaryotes: ongoing and significant? | the expansion of genome sequencing projects has produced accumulating evidence for lateral transfer of genes between prokaryotic and eukaryotic genomes. however, it remains controversial whether these genes are of functional importance in their recipient host. nikoh and nakabachi, in a recent paper in bmc biology, take a first step and show that two genes of bacterial origin are highly expressed in the pea aphid acyrthosiphon pisum. active gene expression of transferred genes is supported by thr ... | 2009 | 19416510 |
| immunity and other defenses in pea aphids, acyrthosiphon pisum. | recent genomic analyses of arthropod defense mechanisms suggest conservation of key elements underlying responses to pathogens, parasites and stresses. at the center of pathogen-induced immune responses are signaling pathways triggered by the recognition of fungal, bacterial and viral signatures. these pathways result in the production of response molecules, such as antimicrobial peptides and lysozymes, which degrade or destroy invaders. using the recently sequenced genome of the pea aphid (acyr ... | 2010 | 20178569 |
| interspecific symbiont transfection confers a novel ecological trait to the recipient insect. | in japan, pea aphids acyrthosiphon pisum mainly feed on vetch and clover, and many aphid clones produce more progeny on vetch than on clover. in this context, particular genotypes of the facultative symbiont regiella insecticola enhance reproduction of infected pea aphids specifically on clover, thereby broadening the suitable food plant range of the insect. a species that is sympatric to a. pisum, vetch aphids megoura crassicauda, are commonly found on vetch but not on clover. laboratory rearin ... | 2010 | 20880856 |
| conditional facilitation of an aphid vector, acyrthosiphon pisum, by the plant pathogen, pea enation mosaic virus. | plant pathogens can induce symptoms that affect the performance of insect herbivores utilizing the same host plant. previous studies examining the effects of infection of tic bean, vicia faba l. (fabales: fabaceae), by pea enation mosaic virus (pemv), an important disease of legume crops, indicated there were no changes in the growth and reproductive rate of its primary vector the pea aphid, acyrthosiphon pisum (harris) (hemiptera: aphididae). here, we report the results of laboratory experiment ... | 2010 | 21067425 |
| phylomedb v3.0: an expanding repository of genome-wide collections of trees, alignments and phylogeny-based orthology and paralogy predictions. | the growing availability of complete genomic sequences from diverse species has brought about the need to scale up phylogenomic analyses, including the reconstruction of large collections of phylogenetic trees. here, we present the third version of phylomedb (http://phylomedb.org), a public database for genome-wide collections of gene phylogenies (phylomes). currently, phylomedb is the largest phylogenetic repository and hosts 17 phylomes, comprising 416,093 trees and 165,840 alignments. it is a ... | 2010 | 21075798 |
| deep sequencing of the transcriptomes of soybean aphid and associated endosymbionts. | the soybean aphid has significantly impacted soybean production in the u.s. transcriptomic analyses were conducted for further insight into leads for potential novel management strategies. | 2012 | 22984624 |
| escherichia coli k-12 pathogenicity in the pea aphid, acyrthosiphon pisum, reveals reduced antibacterial defense in aphids. | to better understand the molecular basis underlying aphid immune tolerance to beneficial bacteria and immune defense to pathogenic bacteria, we characterized how the pea aphid acyrthosiphon pisum responds to escherichia coli k-12 infections. e. coli bacteria, usually cleared in the hemolymph of other insect species, were capable of growing exponentially and killing aphids within a few days. red fluorescence protein expressing e. coli k-12 laboratory strain multiplied in the aphid hemolymph as we ... | 2011 | 21527277 |
| cellular mechanism for selective vertical transmission of an obligate insect symbiont at the bacteriocyte-embryo interface. | many insects are associated with obligate symbiotic bacteria, which are localized in specialized cells called bacteriocytes, vertically transmitted through host generations via ovarial passage, and essential for growth and reproduction of their hosts. although vertical transmission is pivotal for maintenance of such intimate host-symbiont associations, molecular and cellular mechanisms underlying the process are largely unknown. here we report a cellular mechanism for vertical transmission of th ... | 2012 | 22517738 |
| the central role of the host cell in symbiotic nitrogen metabolism. | symbiotic nitrogen recycling enables animals to thrive on nitrogen-poor diets and environments. it traditionally refers to the utilization of animal waste nitrogen by symbiotic micro-organisms to synthesize essential amino acids (eaas), which are translocated back to the animal host. we applied metabolic modelling and complementary metabolite profiling to investigate nitrogen recycling in the symbiosis between the pea aphid and the intracellular bacterium buchnera, which synthesizes eaas. the re ... | 2012 | 22513857 |
| parasitic wasp responses to symbiont-based defense in aphids. | recent findings indicate that several insect lineages receive protection against particular natural enemies through infection with heritable symbionts, but little is yet known about whether enemies are able to discriminate and respond to symbiont-based defense. the pea aphid, acyrthosiphon pisum, receives protection against the parasitic wasp, aphidius ervi, when infected with the bacterial symbiont hamiltonella defensa and its associated bacteriophage apse (acyrthosiphon pisum secondary endosym ... | 2012 | 22364271 |
| dickeya dadantii, a plant pathogenic bacterium producing cyt-like entomotoxins, causes septicemia in the pea aphid acyrthosiphon pisum. | dickeya dadantii (syn. erwinia chrysanthemi) is a plant pathogenic bacteria that harbours a cluster of four horizontally-transferred, insect-specific toxin genes. it was recently shown to be capable of causing an acute infection in the pea aphid acyrthosiphon pisum (insecta: hemiptera). the infection route of the pathogen, and the role and in vivo expression pattern of these toxins, remain unknown. using bacterial numeration and immunolocalization, we investigated the kinetics and the pattern of ... | 2012 | 22292023 |
| aphid amino acid transporter regulates glutamine supply to intracellular bacterial symbionts. | endosymbiotic associations have played a major role in evolution. however, the molecular basis for the biochemical interdependence of these associations remains poorly understood. the aphid-buchnera endosymbiosis provides a powerful system to elucidate how these symbioses are regulated. in aphids, the supply of essential amino acids depends on an ancient nutritional symbiotic association with the gamma-proteobacterium buchnera aphidicola. buchnera cells are densely packed in specialized aphid ba ... | 2013 | 24367072 |
| proteomic investigation of aphid honeydew reveals an unexpected diversity of proteins. | aphids feed on the phloem sap of plants, and are the most common honeydew-producing insects. while aphid honeydew is primarily considered to comprise sugars and amino acids, its protein diversity has yet to be documented. here, we report on the investigation of the honeydew proteome from the pea aphid acyrthosiphon pisum. using a two-dimensional differential in-gel electrophoresis (2d-dige) approach, more than 140 spots were isolated, demonstrating that aphid honeydew also represents a diverse s ... | 2013 | 24086359 |
| genome expansion and differential expression of amino acid transporters at the aphid/buchnera symbiotic interface. | in insects some of the most ecologically important symbioses are nutritional symbioses that provide hosts with novel traits and thereby facilitate exploitation of otherwise inaccessible niches. one such symbiosis is the ancient obligate intracellular symbiosis of aphids with the γ-proteobacteria, buchnera aphidicola. while the nutritional basis of the aphid/buchnera symbiosis is well understood, the processes and structures that mediate the intimate interactions of symbiotic partners remain unch ... | 2011 | 21613235 |
| environment exploration and colonization behavior of the pea aphid associated with the expression of the foraging gene. | aphids respond to specific environmental cues by producing alternative morphs, a phenomenon called polyphenism, but also by modulating their individual behavior even within the same morph. this complex plasticity allows a rapid adaptation of individuals to fluctuating environmental conditions, but the underlying genetic and molecular mechanisms remain largely unknown. the foraging gene is known to be associated with behavior in various species and has been shown to mediate the behavioral shift i ... | 2013 | 23734236 |
| tyrosine pathway regulation is host-mediated in the pea aphid symbiosis during late embryonic and early larval development. | nutritional symbioses play a central role in insects' adaptation to specialized diets and in their evolutionary success. the obligatory symbiosis between the pea aphid, acyrthosiphon pisum, and the bacterium, buchnera aphidicola, is no exception as it enables this important agricultural pest insect to develop on a diet exclusively based on plant phloem sap. the symbiotic bacteria provide the host with essential amino acids lacking in its diet but necessary for the rapid embryonic growth seen in ... | 2013 | 23575215 |
| genomic analysis of the regulatory elements and links with intrinsic dna structural properties in the shrunken genome of buchnera. | buchnera aphidicola is an obligate symbiotic bacterium, associated with most of the aphididae, whose genome has drastically shrunk during intracellular evolution. gene regulation in buchnera has been a matter of controversy in recent years as the combination of genomic information with the experimental results has been contradictory, refuting or arguing in favour of a functional and responsive transcription regulation in buchnera.the goal of this study was to describe the gene transcription regu ... | 2013 | 23375088 |
| potential use of a serpin from arabidopsis for pest control. | although genetically modified (gm) plants expressing toxins from bacillus thuringiensis (bt) protect agricultural crops against lepidopteran and coleopteran pests, field-evolved resistance to bt toxins has been reported for populations of several lepidopteran species. moreover, some important agricultural pests, like phloem-feeding insects, are not susceptible to bt crops. complementary pest control strategies are therefore necessary to assure that the benefits provided by those insect-resistant ... | 2011 | 21655276 |
| presence of a functional (ttagg)(n) telomere-telomerase system in aphids. | the structure of the telomeres of four aphid species (acyrthosiphon pisum, megoura viciae, myzus persicae and rhopalosiphum padi) was evaluated by southern blotting and fluorescent in situ hybridization, revealing that each chromosomal end consists of a (ttagg)(n) repeat. the presence of a telomerase coding gene has been verified successively in the a. pisum genome, revealing that aphid telomerase shares sequence identity ranging from 12% to 18% with invertebrate and vertebrate homologues, and p ... | 2011 | 21667174 |
| facultative symbiont infections affect aphid reproduction. | some bacterial symbionts alter their hosts reproduction through various mechanisms that enhance their transmission in the host population. in addition to its obligatory symbiont buchnera aphidicola, the pea aphid acyrthosiphon pisum harbors several facultative symbionts influencing several aspects of host ecology. aphids reproduce by cyclical parthenogenesis whereby clonal and sexual reproduction alternate within the annual life cycle. many species, including the pea aphid, also show variation i ... | 2011 | 21818272 |
| a substrate ambiguous enzyme facilitates genome reduction in an intracellular symbiont. | genome evolution in intracellular microbial symbionts is characterized by gene loss, generating some of the smallest and most gene-poor genomes known. as a result of gene loss these genomes commonly contain metabolic pathways that are fragmented relative to their free-living relatives. the evolutionary retention of fragmented metabolic pathways in the gene-poor genomes of endosymbionts suggests that they are functional. however, it is not always clear how they maintain functionality. to date, th ... | 2014 | 25527092 |
| comparative transcriptomic analyses revealed divergences of two agriculturally important aphid species. | grain aphid (sitobion avenae f) and pea aphid (acyrthosiphon pisum) are two agriculturally important pest species, which cause significant yield losses to crop plants each year by inflicting damage both through the direct effects of feeding and by vectoring debilitating plant viruses. although a close phylogenetic relationship between grain aphid and pea aphid was proposed, the biological variations between these two aphid species are obvious. while the host ranges of grain aphid is restricted t ... | 2014 | 25424897 |
| adenine methylation may contribute to endosymbiont selection in a clonal aphid population. | the pea aphid acyrthosiphon pisum has two modes of reproduction: parthenogenetic during the spring and summer and sexual in autumn. this ability to alternate between reproductive modes and the emergence of clonal populations under favorable conditions make this organism an interesting model for genetic and epigenetic studies. the pea aphid hosts different types of endosymbiotic bacteria within bacteriocytes which help the aphids survive and adapt to new environmental conditions and habitats. the ... | 2014 | 25406741 |
| acyrthosiphon pisum aqp2: a multifunctional insect aquaglyceroporin. | annotation of the recently sequenced genome of the pea aphid (acyrthosiphon pisum) identified a gene apaqp2 (acypi009194, gene id: 100168499) with homology to the major intrinsic protein/aquaporin superfamily of membrane channel proteins. phylogenetic analysis suggests that apaqp2 is a member of an insect-specific clade of this superfamily. homology model structures of apaqp2 showed a novel array of amino acids comprising the substrate selectivity-determining "aromatic/arginine" region of the pu ... | 2011 | 22166843 |
| identification and characterization of a novel legume-like lectin cdna sequence from the red marine algae gracilaria fisheri. | a legume-type lectin (l-lectin) gene of the red algae gracilaria fisheri (gfl) was cloned by rapid amplification of cdna ends (race). the full-length cdna of gfl was 1714 bp and contained a 1542 bp open reading frame encoding 513 amino acids with a predicted molecular mass of 56.5 kda. analysis of the putative amino acid sequence with ncbi-blast revealed a high homology (30-68%) with legume-type lectins (l-lectin) from griffithsia japonica, clavispora lusitaniae, acyrthosiphon pisum, tetraodon n ... | 2011 | 22116281 |
| diversification of mif immune regulators in aphids: link with agonistic and antagonistic interactions. | the widespread use of genome sequencing provided evidences for the high degree of conservation in innate immunity signalling pathways across animal phyla. however, the functioning and evolutionary history of immune-related genes remains unknown for most invertebrate species. a striking observation coming from the analysis of the pea aphid acyrthosiphon pisum genome is the absence of important conserved genes known to be involved in the antimicrobial responses of other insects. this reduction in ... | 2014 | 25193628 |
| factors limiting the spread of the protective symbiont hamiltonella defensa in aphis craccivora aphids. | many insects are associated with heritable symbionts that mediate ecological interactions, including host protection against natural enemies. the cowpea aphid, aphis craccivora, is a polyphagous pest that harbors hamiltonella defensa, which defends against parasitic wasps. despite this protective benefit, this symbiont occurs only at intermediate frequencies in field populations. to identify factors constraining h. defensa invasion in ap. craccivora, we estimated symbiont transmission rates, per ... | 2014 | 25015890 |
| genomic basis of endosymbiont-conferred protection against an insect parasitoid. | bacterial endosymbionts exert a variety of beneficial effects on insect hosts. in pea aphids (acyrthosiphon pisum), several inherited endosymbiont species protect their hosts against parasitoid wasps, which are major natural enemies. however, strains of these symbiont species vary in their ability to confer protection against parasitoids, with some conferring almost complete protection and others conferring almost none. in this study, two strains of the endosymbiont regiella insecticola (r. inse ... | 2011 | 21948522 |
| the basic helix-loop-helix transcription factor family in the pea aphid, acyrthosiphon pisum. | the basic helix-loop-helix (bhlh) proteins play essential roles in a wide range of developmental processes in higher organisms. bhlh family members have been identified in over 20 organisms, including fruit fly, zebrafish, and human. this study identified 54 bhlh family members in the pea aphid, acyrthosiphon pisum (harris) (hemiptera: aphididae), genome. phylogenetic analyses revealed that they belong to 37 bhlh families with 21, 13, 9, 1, 9, and 1 members in group a, b, c, d, e, and f, respect ... | 2011 | 21870970 |
| Serratia symbiotica from the aphid Cinara cedri: a missing link from facultative to obligate insect endosymbiont. | The genome sequencing of Buchnera aphidicola BCc from the aphid Cinara cedri, which is the smallest known Buchnera genome, revealed that this bacterium had lost its symbiotic role, as it was not able to synthesize tryptophan and riboflavin. Moreover, the biosynthesis of tryptophan is shared with the endosymbiont Serratia symbiotica SCc, which coexists with B. aphidicola in this aphid. The whole-genome sequencing of S. symbiotica SCc reveals an endosymbiont in a stage of genome reduction that is ... | 2011 | 22102823 |
| exposure to natural pathogens reveals costly aphid response to fungi but not bacteria. | immune responses are costly, causing trade-offs between defense and other host life history traits. aphids present a special system to explore the costs associated with immune activation since they are missing several humoral and cellular mechanisms thought important for microbial resistance, and it is unknown whether they have alternative, novel immune responses to deal with microbial threat. here we expose pea aphids to an array of heat-killed natural pathogens, which should stimulate immune r ... | 2014 | 24634732 |
| functional analysis of a fatty acid binding protein produced by aphidius ervi teratocytes. | aphidius ervi (hymenoptera, braconidae) is an endophagous parasitoid of various aphid species, including acyrthosiphon pisum (homoptera, aphididae), the model host used in the present study. parasitized hosts show a marked increase of their nutritional suitability for the developing parasitoid larvae. this alteration of the biochemical and metabolic profile is due to a castration process mediated by the combined action of the venom, injected at the oviposition, and of the teratocytes, cells deri ... | 2011 | 22226822 |
| effect of host genotype on symbiont titer in the aphid-buchnera symbiosis. | obligate nutritional symbioses require balance between the energetic needs of the host and the symbiont. the resident symbiont population size within a host may have major impacts on host fitness, as both host and symbiont consume and supply metabolites in a shared metabolite pool. given the massive genome degradation that is a hallmark of bacterial endosymbionts of insects, it is unclear at what level these populations are regulated, and how regulation varies among hosts within natural populati ... | 2011 | 26467737 |
| novel male-biased expression in paralogs of the aphid slimfast nutrient amino acid transporter expansion. | a major goal of molecular evolutionary biology is to understand the fate and consequences of duplicated genes. in this context, aphids are intriguing because the newly sequenced pea aphid genome harbors an extraordinary number of lineage-specific gene duplications relative to other insect genomes. though many of their duplicated genes may be involved in their complex life cycle, duplications in nutrient amino acid transporters appear to be associated rather with their essential amino acid poor d ... | 2011 | 21917168 |
| genetic and metabolic determinants of nutritional phenotype in an insect-bacterial symbiosis. | the pervasive influence of resident microorganisms on the phenotype of their hosts is exemplified by the intracellular bacterium buchnera aphidicola, which provides its aphid partner with essential amino acids (eaas). we investigated variation in the dietary requirement for eaas among four pea aphid (acyrthosiphon pisum) clones. buchnera-derived nitrogen contributed to the synthesis of all eaas for which aphid clones required a dietary supply, and to none of the eaas for which all four clones ha ... | 2011 | 21392141 |
| evidence for specificity in symbiont-conferred protection against parasitoids. | many insects harbour facultative symbiotic bacteria, some of which have been shown to provide resistance against natural enemies. one of the best-known protective symbionts is hamiltonella defensa, which in pea aphid (acyrthosiphon pisum) confers resistance against attack by parasitoid wasps in the genus aphidius (braconidae).we asked (i) whether this symbiont also confers protection against a phylogenetically distant group of parasitoids (aphelinidae) and (ii) whether there are consistent diffe ... | 2015 | 26136451 |
| the genome of diuraphis noxia, a global aphid pest of small grains. | the russian wheat aphid, diuraphis noxia kurdjumov, is one of the most important pests of small grains throughout the temperate regions of the world. this phytotoxic aphid causes severe systemic damage symptoms in wheat, barley, and other small grains as a direct result of the salivary proteins it injects into the plant while feeding. | 2015 | 26044338 |
| infection dynamic of symbiotic bacteria in the pea aphid acyrthosiphon pisum gut and host immune response at the early steps in the infection process. | in addition to its obligatory symbiont buchnera aphidicola, the pea aphid acyrthosiphon pisum can harbor several facultative bacterial symbionts which can be mutualistic in the context of various ecological interactions. belonging to a genus where many members have been described as pathogen in invertebrates, serratia symbiotica is one of the most common facultative partners found in aphids. the recent discovery of strains able to grow outside their host allowed us to simulate environmental acqu ... | 2015 | 25811863 |
| bacterial communities associated with host-adapted populations of pea aphids revealed by deep sequencing of 16s ribosomal dna. | associations between microbes and animals are ubiquitous and hosts may benefit from harbouring microbial communities through improved resource exploitation or resistance to environmental stress. the pea aphid, acyrthosiphon pisum, is the host of heritable bacterial symbionts, including the obligate endosymbiont buchnera aphidicola and several facultative symbionts. while obligate symbionts supply aphids with key nutrients, facultative symbionts influence their hosts in many ways such as protecti ... | 2015 | 25807173 |
| experimental replacement of an obligate insect symbiont. | symbiosis, the close association of unrelated organisms, has been pivotal in biological diversification. in the obligate symbioses found in many insect hosts, organisms that were once independent are permanently and intimately associated, resulting in expanded ecological capabilities. the primary model for this kind of symbiosis is the association between the bacterium buchnera and the pea aphid (acyrthosiphon pisum). a longstanding obstacle to efforts to illuminate genetic changes underlying ob ... | 2015 | 25561531 |
| modulation of legume defense signaling pathways by native and non-native pea aphid clones. | the pea aphid (acyrthosiphon pisum) is a complex of at least 15 genetically different host races that are native to specific legume plants, but can all develop on the universal host plant vicia faba. despite much research, it is still unclear why pea aphid host races (biotypes) are able to colonize their native hosts while other host races are not. all aphids penetrate the plant and salivate into plant cells when they test plant suitability. thus plants might react differently to the various pea ... | 2016 | 28018405 |
| symbiotic bacterium modifies aphid body color. | color variation within populations of the pea aphid influences relative susceptibility to predators and parasites. we have discovered that infection with a facultative endosymbiont of the genus rickettsiella changes the insects' body color from red to green in natural populations. approximately 8% of pea aphids collected in western europe carried the rickettsiella infection. the infection increased amounts of blue-green polycyclic quinones, whereas it had less of an effect on yellow-red caroteno ... | 2010 | 21097935 |
| large-scale label-free quantitative proteomics of the pea aphid-buchnera symbiosis. | many insects are nutritionally dependent on symbiotic microorganisms that have tiny genomes and are housed in specialized host cells called bacteriocytes. the obligate symbiosis between the pea aphid acyrthosiphon pisum and the ?-proteobacterium buchnera aphidicola (only 584 predicted proteins) is particularly amenable for molecular analysis because the genomes of both partners have been sequenced. to better define the symbiotic relationship between this aphid and buchnera, we used large-scale, ... | 2011 | 21421797 |
| disruption of phenylalanine hydroxylase reduces adult lifespan and fecundity, and impairs embryonic development in parthenogenetic pea aphids. | phenylalanine hydroxylase (pah) is a key tyrosine-biosynthetic enzyme involved in neurological and melanin-associated physiological processes. despite extensive investigations in holometabolous insects, a pah contribution to insect embryonic development has never been demonstrated. here, we have characterized, for the first time, the pah gene in a hemimetabolous insect, the aphid acyrthosiphon pisum. phylogenetic and sequence analyses confirmed that appah is closely related to metazoan pah, exhi ... | 2016 | 27694983 |
| analysis of expressed sequence tags from maize mosaic rhabdovirus-infected gut tissues of peregrinus maidis reveals the presence of key components of insect innate immunity. | the corn planthopper, peregrinus maidis, causes direct feeding damage to plants and transmits maize mosaic rhabdovirus (mmv) in a persistent-propagative manner. mmv must cross several insect tissue layers for successful transmission to occur, and the gut serves as an important barrier for rhabdovirus transmission. in order to facilitate the identification of proteins that may interact with mmv either by facilitating acquisition or responding to virus infection, we generated and analysed the gut ... | 2011 | 21199018 |
| characterisation of immune responses in the pea aphid, acyrthosiphon pisum. | the innate immune system of insects provides effective defence against a range of parasites and pathogens. the pea aphid, acyrthosiphon pisum, is a novel study system for investigating host-parasite interactions due to its complex associations with both well-characterised bacterial symbionts and a diversity of pathogens and parasites, including several important biological control agents. however, little is known about the cellular and humoral immune responses of aphids. here we identify three m ... | 2011 | 21439291 |
| de novo transcriptome assembly of the grapevine phylloxera allows identification of genes differentially expressed between leaf- and root-feeding forms. | grapevine phylloxera, an insect related to true aphids, is a major historic pest of viticulture only controlled through the selection of resistant rootstocks or through quarantine regulations where grapevine is cultivated own-rooted. transcriptomic data could help understand the bases of its original life-traits, including a striking case of polyphenism, with forms feeding on roots and forms feeding in leaf-galls. comparisons with true aphids (for which complete genomes have been sequenced) shou ... | 2016 | 26968158 |
| aphid genome expression reveals host-symbiont cooperation in the production of amino acids. | the evolution of intimate symbiosis requires the coordination of gene expression and content between the distinct partner genomes; this coordination allows the fusion of capabilities of each organism into a single integrated metabolism. in aphids, the 10 essential amino acids are scarce in the phloem sap diet and are supplied by the obligate bacterial endosymbiont (buchnera), which lives inside specialized cells called bacteriocytes. although buchnera's genome encodes most genes for essential am ... | 2011 | 21282658 |
| interaction of the bacillus thuringiensis delta endotoxins cry1ac and cry3aa with the gut of the pea aphid, acyrthosiphon pisum (harris). | hemipteran pests including aphids are not particularly susceptible to the effects of insecticidal cry toxins derived from the bacterium bacillus thuringiensis. we examined the physiological basis for the relatively low toxicity of cry1ac and cry3aa against the pea aphid, acyrthosiphon pisum (harris). cry1ac was efficiently hydrolyzed by aphid stomach membrane associated cysteine proteases (cp) producing a 60kda mature toxin, whereas cry3aa was incompletely processed and partially degraded. cry1a ... | 2011 | 21300068 |
| two odorant-binding proteins mediate the behavioural response of aphids to the alarm pheromone (e)-ß-farnesene and structural analogues. | aphids are agricultural pests of great economical interest. alternatives to insecticides, using semiochemicals, are of difficult applications. in fact, sex pheromones are of little use as aphids reproduce partenogenetically most of the time. besides, the alarm pheromone, (e)-ß-farnesene for a great number of species, is difficult to synthesize and unstable in the environment. the search for novel semiochemicals to be used in population control can be efficiently approached through the study of t ... | 2012 | 22427877 |
| drawing the line. | the pea aphid acyrthosiphon pisum is an agriculturally important pest of leguminous plants including peas and broad beans. the widespread use of chemical pesticides impacts heavily on the environment, and increases pesticide-resistant pea aphid populations, so alternative strategies are being actively sought. pseudomonas syringae bacteria are known to infect and kill the pea aphid, and offer a possible control strategy. in this study, the authors measured the effects of injecting p. syringae on ... | 2015 | 26438421 |
| a highly infective plant-associated bacterium influences reproductive rates in pea aphids. | pea aphids, acyrthosiphon pisum, have the potential to increase reproduction as a defence against pathogens, though how frequently this occurs or how infection with live pathogens influences this response is not well understood. here we determine the minimum infective dose of an environmentally common bacterium and possible aphid pathogen, pseudomonas syringae, to determine the likelihood of pathogenic effects to pea aphids. additionally, we used p. syringae infection to investigate how live pat ... | 2016 | 26998321 |
| identification of distinct quantitative trait loci associated with defence against the closely related aphids acyrthosiphon pisum and a. kondoi in medicago truncatula. | aphids are a major family of plant insect pests. medicago truncatula and acyrthosiphon pisum (pea aphid, pa) are model species with a suite of resources available to help dissect the mechanism underlying plant-aphid interactions. a previous study focused on monogenic and relatively strong resistance in m. truncatula to pa and other aphid species. in this study a moderate resistance to pa was characterized in detail in the m. truncatula line a17 and compared with the highly susceptible line a20 a ... | 2012 | 22442407 |
| up-regulation of abscisic acid signaling pathway facilitates aphid xylem absorption and osmoregulation under drought stress. | the activation of the abscisic acid (aba) signaling pathway reduces water loss from plants challenged by drought stress. the effect of drought-induced aba signaling on the defense and nutrition allocation of plants is largely unknown. we postulated that these changes can affect herbivorous insects. we studied the effects of drought on different feeding stages of pea aphids in the wild-type a17 of medicago truncatula and aba signaling pathway mutant sta-1. we examined the impact of drought on pla ... | 2015 | 26546578 |
| responses of the pea aphid transcriptome to infection by facultative symbionts. | serratia symbiotica is a facultative symbiont of pea aphids (acyrthosiphon pisum) that provides tolerance to heat stress. although the phenotypic effects of facultative symbionts upon hosts have been studied in some detail, little is known about the molecular and genomic basis of these interactions. previous studies show a large impact of s. symbiotica upon the aphid metabolome. whole-genome transcriptional profiling and next-generation sequencing demonstrated expression of 94% of refseq genes f ... | 2011 | 21382108 |
| protein digestion in cereal aphids (sitobion avenae) as a target for plant defence by endogenous proteinase inhibitors. | gut extracts from cereal aphids (sitobion avenae) showed significant levels of proteolytic activity, which was inhibited by reagents specific for cysteine proteases and chymotrypsin-like proteases. gut tissue contained cdnas encoding cathepsin b-like cysteine proteinases, similar to those identified in the closely related pea aphid (acyrthosiphon pisum). analysis of honeydew (liquid excreta) from cereal aphids fed on diet containing ovalbumin showed that digestion of ingested proteins occurred i ... | 2011 | 21477592 |
| endogenous rna viruses of plants in insect genomes. | endogenous viral elements (eves) derived from rna viruses with no dna stage are rare, especially those where the parental viruses possess single-strand positive-sense (ssrna+) genomes. here we provide evidence that eves that share a sequence similarity to ssrna+viruses of plants are integrated into the genomes of a number of insects, including mosquito, fruit flies, bees, ant, silkworm, pea aphid, monarch butterfly, and wasps. a preliminary phylogenetic analysis places these eves as divergent re ... | 2012 | 22410578 |
| angiotensin-converting enzymes modulate aphid-plant interactions. | angiotensin-converting enzymes (aces) are key components of the renin-angiotensin system in mammals. however, the function of ace homologs in insect saliva is unclear. aphids presumably deliver effector proteins via saliva into plant cells to maintain a compatible insect-plant interaction. in this study, we showed that ace modulates aphid-plant interactions by affecting feeding behavior and survival of aphids on host plants. three ace genes were identified from the pea aphid acyrthosiphon pisum ... | 2015 | 25744345 |
| transcriptome analysis of green peach aphid (myzus persicae): insight into developmental regulation and inter-species divergence. | green peach aphid (myzus persicae) and pea aphid (acyrthosiphon pisum) are two phylogenetically closely related agricultural pests. while pea aphid is restricted to fabaceae, green peach aphid feeds on hundreds of plant species from more than 40 families. transcriptome comparison could shed light on the genetic factors underlying the difference in host range between the two species. furthermore, a large scale study contrasting gene expression between immature nymphs and fully developed adult aph ... | 2016 | 27812361 |
| gene knockdown by rnai in the pea aphid acyrthosiphon pisum. | rna interference (rnai) is a powerful method to inhibit gene expression in a sequence specific manner. | 2007 | 17903251 |
| comparative profiling of micrornas in the winged and wingless english grain aphid, sitobion avenae (f.) (homoptera: aphididae). | micrornas (mirnas) are short single-stranded non-coding rnas that regulate gene expression, particularly during development. in this study, 345 mirnas were identified from the english green aphid, sitobion avenae (f.), of which 168 were conserved and 177 were s. avenae-specific. quantitative comparison of mirna expression levels indicated that 16 and 12 mirnas were significantly up-regulated in winged and wingless s. avenae small rna libraries, respectively. differential expression of these mirn ... | 2016 | 27762301 |
| de novo assembly and characterization of a maternal and developmental transcriptome for the emerging model crustacean parhyale hawaiensis. | arthropods are the most diverse animal phylum, but their genomic resources are relatively few. while the genome of the branchiopod daphnia pulex is now available, no other large-scale crustacean genomic resources are available for comparison. in particular, genomic resources are lacking for the most tractable laboratory model of crustacean development, the amphipod parhyale hawaiensis. insight into shared and divergent characters of crustacean genomes will facilitate interpretation of future dev ... | 2011 | 22118449 |
| expansion of the mirna pathway in the hemipteran insect acyrthosiphon pisum. | the pathways that allow short noncoding rnas such as the micrornas (mirnas) to mediate gene regulation and control critical cellular and developmental processes involve a limited number of key protein components. these proteins are the dicer-like rnases, double-stranded rna (dsrna)-binding proteins, and the argonaute (ago) proteins that process stem-loop hairpin transcripts of endogenous genes to generate mirnas or long dsrna precursors (either exogenous or endogenous). comparative genomics stud ... | 2010 | 20179251 |
| chromatin-remodelling proteins of the pea aphid, acyrthosiphon pisum (harris). | aphids display extraordinary developmental plasticity in response to environmental cues. these differential responses to environmental changes may be due in part to changes in gene expression patterns. to understand the molecular basis for aphid developmental plasticity, we attempted to identify the chromatin-remodelling machinery in the recently sequenced pea aphid genome. we find that the pea aphid possesses a complement of metazoan histone modifying enzymes with greater gene family diversity ... | 0 | 20482651 |
| aphids transform and detoxify the mycotoxin deoxynivalenol via a type ii biotransformation mechanism yet unknown in animals. | biotransformation of mycotoxins in animals comprises phase i and phase ii metabolisation reactions. for the trichothecene deoxynivalenol (don), several phase ii biotransformation reactions have been described resulting in don-glutathiones, don-glucuronides and don-sulfates made by glutathione-s-transferases, uridine-diphosphoglucuronyl transferases and sulfotransferases, respectively. these metabolites can be easily excreted and are less toxic than their free compounds. here, we demonstrate for ... | 2016 | 27929076 |
| individual and population variation in invertebrates revealed by inter-simple sequence repeats (issrs). | pcr-based molecular markers are well suited for questions requiring large scale surveys of plant and animal populations. inter-simple sequence repeats or issrs are analyzed by a recently developed technique based on the amplification of the regions between inverse-oriented microsatellite loci with oligonucleotides anchored in microsatellites themselves. issrs have shown much promise for the study of the population biology of plants, but have not yet been explored for similar studies of animals. ... | 2001 | 15455068 |
| a genome-wide identification and analysis of the basic helix-loop-helix transcription factors in brown planthopper, nilaparvata lugens. | the basic helix-loop-helix (bhlh) transcription factors in insects play essential roles in multiple developmental processes including neurogenesis, sterol metabolism, circadian rhythms, organogenesis and formation of olfactory sensory neurons. the identification and function analysis of bhlh family members of the most destructive insect pest of rice, nilaparvata lugens, may provide novel tools for pest management. here, a genome-wide survey for bhlh sequences identified 60 bhlh sequences (nlbhlh ... | 2016 | 27869716 |
| rnai knockdown of a salivary transcript leading to lethality in the pea aphid, acyrthosiphon pisum. | abstract injection of sirna (small interfering rna) into parthenogenetic adult pea aphids (acyrthosiphon pisum) is shown here to lead to depletion of a target salivary gland transcript. the sirna was generated from double stranded rna that covered most of the open reading frame of the transcript, which we have called coo2. the coo2 transcript level decreases dramatically over a 3-day period after injection of sirna. with a lag of 1 to 2 days, the sicoo2-rna injected insects died, on average 8 da ... | 0 | 20233093 |
| deep rna-seq profile reveals biodiversity, plant-microbe interactions and a large family of nbs-lrr resistance genes in walnut (juglans regia) tissues. | deep rna-seq profiling, a revolutionary method used for quantifying transcriptional levels, often includes non-specific transcripts from other co-existing organisms in spite of stringent protocols. using the recently published walnut genome sequence as a filter, we present a broad analysis of the rna-seq derived transcriptome profiles obtained from twenty different tissues to extract the biodiversity and possible plant-microbe interactions in the walnut ecosystem in california. since the residua ... | 2016 | 26883051 |
| insulin-related peptide 5 is involved in regulating embryo development and biochemical composition in pea aphid with wing polyphenism. | in aphids there is a fecundity-dispersal trade-off between wingless and winged morphs. recent research on the molecular mechanism of wing morphs associated with dispersal reveals that insulin receptors in the insulin signaling (is) pathway regulate alternation of wing morphs in planthoppers. however, little is known about whether genes in the is pathway are involved in developmental regulation in aphid nymphs with different wing morphs. in this study, we show that expression of the insulin-relat ... | 2016 | 26903881 |
| molecular characterization of the aphis gossypii olfactory receptor gene families. | the cotton aphid, aphis gossypii glover, is a polyphagous pest that inflicts great damage to cotton yields worldwide. antennal olfaction, which is extremely important for insect survival, mediates key behaviors such as host preference, mate choice, and oviposition site selection. in insects, odor detection is mediated by odorant receptors (ors) and ionotropic receptors (irs), which ensure the specificity of the olfactory sensory neuron responses. in this study, our aim is to identify chemosensor ... | 2014 | 24971460 |
| retargeting of the bacillus thuringiensis toxin cyt2aa against hemipteran insect pests. | although transgenic crops expressing bacillus thuringiensis (bt) toxins have been used successfully for management of lepidopteran and coleopteran pest species, the sap-sucking insects (hemiptera) are not particularly susceptible to bt toxins. to overcome this limitation, we demonstrate that addition of a short peptide sequence selected for binding to the gut of the targeted pest species serves to increase toxicity against said pest. insertion of a 12-aa pea aphid gut-binding peptide by adding t ... | 2013 | 23650347 |
| the evolution of the histone methyltransferase gene su(var)3-9 in metazoans includes a fusion with and a re-fission from a functionally unrelated gene. | in eukaryotes, histone h3 lysine 9 (h3k9) methylation is a common mechanism involved in gene silencing and the establishment of heterochromatin. the loci of the major heterochromatic h3k9 methyltransferase su(var)3-9 and the functionally unrelated gamma subunit of the translation initiation factor eif2 are fused in drosophila melanogaster. here we examined the phylogenetic distribution of this unusual gene fusion and the molecular evolution of the h3k9 hmtase su(var)3-9. | 2006 | 16512904 |
| expansion of genes encoding pirna-associated argonaute proteins in the pea aphid: diversification of expression profiles in different plastic morphs. | piwi-interacting rnas (pirnas) are known to regulate transposon activity in germ cells of several animal models that propagate sexually. however, the role of pirnas during asexual reproduction remains almost unknown. aphids that can alternate sexual and asexual reproduction cycles in response to seasonal changes of photoperiod provide a unique opportunity to study pirnas and the pirna pathway in both reproductive modes. taking advantage of the recently sequenced genome of the pea aphid acyrthosi ... | 2011 | 22162754 |
| similar patterns of linkage disequilibrium and nucleotide diversity in native and introduced populations of the pea aphid, acyrthosiphon pisum. | the pea aphid, acyrthosiphon pisum, is an emerging genomic model system for studies of polyphenisms, bacterial symbioses, host-plant specialization, and the vectoring of plant viruses. here we provide estimates of nucleotide diversity and linkage disequilibrium (ld) in native (european) and introduced (united states) populations of the pea aphid. because introductions can cause population bottlenecks, we hypothesized that u.s. populations harbor lower levels of nucleotide diversity and higher le ... | 2009 | 19470181 |
| evolutionary study of duplications of the mirna machinery in aphids associated with striking rate acceleration and changes in expression profiles. | the sequencing of the genome of the pea aphid acyrthosiphon pisum revealed an unusual expansion of the mirna machinery, with two argonaute-1, two dicer-1 and four pasha gene copies. in this report, we have undertaken a deeper evolutionary analysis of the phylogenetic timing of these gene duplications and of the associated selective pressures by sequencing the two copies of ago-1 and dcr-1 in different aphid species of the subfamily aphidinae. we have also carried out an analysis of the expressio ... | 2012 | 23145470 |
| parallel duplication and partial subfunctionalization of β-catenin/armadillo during insect evolution. | β-catenin is a multifunctional scaffolding protein with roles in wnt signaling, cell adhesion, and centrosome separation. here, we report on independent duplications of the insect β-catenin ortholog armadillo (arm) in the red flour beetle tribolium castaneum and the pea aphid acyrthosiphon pisum. detailed sequence analysis shows that in both species, one paralog lost critical residues of the α-catenin binding domain, which is essential for cell adhesion, and accumulated a dramatically higher num ... | 2011 | 21890476 |
| genomic revelations of a mutualism: the pea aphid and its obligate bacterial symbiont. | the symbiosis of the pea aphid acyrthosphion pisum with the bacterium buchnera aphidicola aps represents the best-studied insect obligate symbiosis. here we present a refined picture of this symbiosis by linking pre-genomic observations to new genomic data that includes the complete genomes of the eukaryotic and prokaryotic symbiotic partners. in doing so, we address four issues central to understanding the patterns and processes operating at the a. pisum/buchnera aps interface. these four issue ... | 2011 | 21390549 |
| deep sequencing of organ- and stage-specific micrornas in the evolutionarily basal insect blattella germanica (l.) (dictyoptera, blattellidae). | micrornas (mirnas) have been reported as key regulators at post-transcriptional level in eukaryotic cells. in insects, most of the studies have focused in holometabolans while only recently two hemimetabolans (locusta migratoria and acyrthosiphon pisum) have had their mirnas identified. therefore, the study of the mirnas of the evolutionarily basal hemimetabolan blattella germanica may provide valuable insights on the structural and functional evolution of mirnas. | 2011 | 21552535 |
| genome-wide annotation and functional identification of aphid glut-like sugar transporters. | phloem feeding insects, such as aphids, feed almost continuously on plant phloem sap, a liquid diet that contains high concentrations of sucrose (a disaccharide comprising of glucose and fructose). to access the available carbon, aphids hydrolyze sucrose in the gut lumen and transport its constituent monosaccharides, glucose and fructose. although sugar transport plays a critical role in aphid nutrition, the molecular basis of sugar transport in aphids, and more generally across all insects, rem ... | 2014 | 25091229 |
| aphids: a model for polyphenism and epigenetics. | environmental conditions can alter the form, function, and behavior of organisms over short and long timescales, and even over generations. aphid females respond to specific environmental cues by transmitting signals that have the effect of altering the development of their offspring. these epigenetic phenomena have positioned aphids as a model for the study of phenotypic plasticity. the molecular basis for this epigenetic inheritance in aphids and how this type of inheritance system could have ... | 2012 | 22567389 |
| bioinformatic prediction, deep sequencing of micrornas and expression analysis during phenotypic plasticity in the pea aphid, acyrthosiphon pisum. | post-transcriptional regulation in eukaryotes can be operated through microrna (mirnas) mediated gene silencing. mirnas are small (18-25 nucleotides) non-coding rnas that play crucial role in regulation of gene expression in eukaryotes. in insects, mirnas have been shown to be involved in multiple mechanisms such as embryonic development, tissue differentiation, metamorphosis or circadian rhythm. insect mirnas have been identified in different species belonging to five orders: coleoptera, dipter ... | 2010 | 20444247 |
| transcriptome analysis of sexually dimorphic chinese white wax scale insects reveals key differences in developmental programs and transcription factor expression. | the chinese white wax scale insect, ericerus pela, represents one of the most dramatic examples of sexual dimorphism in any insect species. in this study, we showed that although e. pela males display complete metamorphosis similar to holometabolous insects, the species forms the sister group to acyrthosiphon pisum and cluster with hemimetabolous insects. the gene expression profile and gene ontology (go) analyses revealed that the two sexes engaged in distinct developmental programs. in particu ... | 2015 | 25634031 |
| molecular cloning, expression pattern and polymorphisms of nadph-cytochrome p450 reductase in the bird cherry-oat aphid rhopalosiphum padi (l.). | nadph-cytochrome p450 reductase (cpr) plays an important role in the cytochrome p450 (cyp)-mediated metabolism of endogenous and exogenous substrates. cpr has been found to be associated with insecticide metabolism and resistance in many insects. however, information regarding cpr in the bird cherry-oat aphid, rhopalosiphum padi, is unavailable. in the current study, a full-length cdna (2,476 bp) of cpr (rpcpr) encoding 681 amino acids was cloned from r. padi. nucleotide sequence and deduced ami ... | 2016 | 27124302 |
| feeding-based rna interference of a gap gene is lethal to the pea aphid, acyrthosiphon pisum. | the gap gene hunchback (hb) is a key regulator in the anteroposterior patterning of insects. loss-of-function of hb resulted in segmentation defects in the next generation. in this paper, hb expression level was investigated at different developmental stages of the pea aphid, acyrthosiphon pisum (ap). aphb mrna was most early detected at the first instar stage and showed an incontinuous increase in the whole life cycle. ingested rna interference was performed at the second instar stage to knockd ... | 2012 | 23144942 |
| is ecological speciation a major trend in aphids? insights from a molecular phylogeny of the conifer-feeding genus cinara. | in the past decade ecological speciation has been recognized as having an important role in the diversification of plant-feeding insects. aphids are host-specialised phytophagous insects that mate on their host plants and, as such, they are prone to experience reproductive isolation linked with host plant association that could ultimately lead to species formation. the generality of such a scenario remains to be tested through macroevolutionary studies. to explore the prevalence of host-driven s ... | 2013 | 24044736 |
| phage loss and the breakdown of a defensive symbiosis in aphids. | terrestrial arthropods are often infected with heritable bacterial symbionts, which may themselves be infected by bacteriophages. however, what role, if any, bacteriophages play in the regulation and maintenance of insect-bacteria symbioses is largely unknown. infection of the aphid acyrthosiphon pisum by the bacterial symbiont hamiltonella defensa confers protection against parasitoid wasps, but only when h. defensa is itself infected by the phage a. pisum secondary endosymbiont (apse). here, w ... | 2013 | 23193123 |
| transcriptome of dickeya dadantii infecting acyrthosiphon pisum reveals a strong defense against antimicrobial peptides. | the plant pathogenic bacterium dickeya dadantii has recently been shown to be able to kill the aphid acyrthosiphon pisum. while the factors required to cause plant disease are now well characterized, those required for insect pathogeny remain mostly unknown. to identify these factors, we analyzed the transcriptome of the bacteria isolated from infected aphids. more than 150 genes were upregulated and 300 downregulated more than 5-fold at 3 days post infection. no homologue to known toxin genes c ... | 2013 | 23342088 |
| aphids evolved novel secreted proteins for symbiosis with bacterial endosymbiont. | aphids evolved novel cells, called bacteriocytes, that differentiate specifically to harbour the obligatory mutualistic endosymbiotic bacteria buchnera aphidicola. the genome of the host aphid acyrthosiphon pisum contains many orphan genes that display no similarity with genes found in other sequenced organisms, prompting us to hypothesize that some of these orphan genes are related to lineage-specific traits, such as symbiosis. we conducted deep sequencing of bacteriocytes mrna followed by whol ... | 2013 | 23173201 |
| isolation and identification of culturable bacteria from honeydew of whitefly, bemisia tabaci (g.) (hemiptera: aleyrodidae). | bemisia tabaci (g.) is an important pest and a vector of gemini viruses infecting plants. during the process of feeding b. tabaci excretes honeydew which is rich in nutrients, and an excellent medium for microbial growth. recent report proved that volatile emitted by the honeydew associated bacteria of aphid, acyrthosiphon pisum harris was involved in natural enemy calling. thus understanding the honeydew associated bacteria is of paramount importance from the non-chemical method of insect pest ... | 2014 | 25606395 |
| whole-genome re-sequencing of non-model organisms: lessons from unmapped reads. | unmapped reads are often discarded from the analysis of whole-genome re-sequencing, but new biological information and insights can be uncovered through their analysis. in this paper, we investigate unmapped reads from the re-sequencing data of 33 pea aphid genomes from individuals specialized on different host plants. the unmapped reads for each individual were retrieved following mapping to the acyrthosiphon pisum reference genome and its mitochondrial and symbiont genomes. these sets of unmap ... | 2014 | 25269379 |