| 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 |
| 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 |
| interaction of allium sativum leaf agglutinin with midgut brush border membrane vesicles proteins and its stability in helicoverpa armigera. | allium sativum leaf agglutinin (asal) binds to several proteins in the midgut of helicoverpa armigera and causes toxicity. most of these were glycosylated. six asal-binding proteins were selected for identification. pmf and ms/ms data showed their similarity with midgut aminopeptidase apn2, polycalins and alkaline phosphatase of h. armigera, cadherin-n protein (partial agap009726-pa) of acyrthosiphon pisum, cytochrome p450 (cyp315a1) of manduca sexta and alkaline phosphatase of heliothis viresce ... | 2010 | 21136596 |
| 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 |
| rapid evolution of parasitoids when faced with the symbiont-mediated resistance of their hosts. | insects harbour a wild diversity of symbionts that can spread and persist within populations by providing benefits to their host. the pea aphid acyrthosiphon pisum maintains a facultative symbiosis with the bacterium hamiltonella defensa, which provides enhanced resistance against the aphid parasitoid aphidius ervi. although the mechanisms associated with this symbiotic-mediated protection have been investigated thoroughly, little is known about its evolutionary effects on parasitoid populations ... | 2011 | 21261770 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| the genome of buchnera aphidicola from the aphid cinara tujafilina provides new clues about the evolutionary history of metabolic losses in bacterial endosymbionts. | the symbiotic association between aphids (homoptera) and buchnera aphidicola (γ-proteobacteria) started about 100-200 million years ago. as a consequence of this relationship, the bacterial genome has undergone a prominent size reduction. the downsize genome process starts when the bacterium enters the host, and will probably end with its extinction and replacement by another healthier bacterium, or with the establishment of metabolic complementation between two or more bacteria. nowadays, sever ... | 2011 | 21571878 |
| 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 |
| 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 |
| microorganisms from aphid honeydew attract and enhance the efficacy of natural enemies. | aphids are one of the most serious pests of crops worldwide, causing major yield and economic losses. to control aphids, natural enemies could be an option but their efficacy is sometimes limited by their dispersal in natural environment. here we report the first isolation of a bacterium from the pea aphid acyrthosiphon pisum honeydew, staphylococcus sciuri, which acts as a kairomone enhancing the efficiency of aphid natural enemies. our findings represent the first case of a host-associated bac ... | 2011 | 21673669 |
| multimodal dynamic response of the buchnera aphidicola pleu plasmid to variations in leucine demand of its host, the pea aphid acyrthosiphon pisum. | aphids, important agricultural pests, can grow and reproduce thanks to their intimate symbiosis with the ?-proteobacterium buchnera aphidicola that furnishes them with essential amino acids lacking in their phloem sap diet. to study how b. aphidicola, with its reduced genome containing very few transcriptional regulators, responds to variations in the metabolic requirements of its host, we concentrated on the leucine metabolic pathway. we show that leucine is a limiting factor for aphid growth a ... | 2011 | 21797941 |
| 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 |
| 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 |
| comparative analysis of the udp-glycosyltransferase multigene family in insects. | udp-glycosyltransferases (ugt) catalyze the conjugation of a range of diverse small lipophilic compounds with sugars to produce glycosides, playing an important role in the detoxification of xenobiotics and in the regulation of endobiotics in insects. recent progress in genome sequencing has enabled an assessment of the extent of the ugt multigene family in insects. here we report over 310 putative ugt genes identified from genomic databases of eight different insect species together with a tran ... | 2011 | 22155036 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| cycads: an annotation database system to ease the development and update of biocyc databases. | in recent years, genomes from an increasing number of organisms have been sequenced, but their annotation remains a time-consuming process. the biocyc databases offer a framework for the integrated analysis of metabolic networks. the pathway tool software suite allows the automated construction of a database starting from an annotated genome, but it requires prior integration of all annotations into a specific summary file or into a genbank file. to allow the easy creation and update of a biocyc ... | 2011 | 21474551 |
| 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 |
| the cellular immune response of the pea aphid to foreign intrusion and symbiotic challenge. | recent studies suggest that the pea aphid (acyrthosiphon pisum) has low immune defenses. however, its immune components are largely undescribed, and notably, extensive characterization of circulating cells has been missing. here, we report characterization of five cell categories in hemolymph of adults of the ll01 pea aphid clone, devoid of secondary symbionts (ss): prohemocytes, plasmatocytes, granulocytes, spherulocytes and wax cells. circulating lipid-filed wax cells are rare; they otherwise ... | 2012 | 22848726 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| matching the supply of bacterial nutrients to the nutritional demand of the animal host. | various animals derive nutrients from symbiotic microorganisms with much-reduced genomes, but it is unknown whether, and how, the supply of these nutrients is regulated. here, we demonstrate that the production of essential amino acids (eaas) by the bacterium buchnera aphidicola in the pea aphid acyrthosiphon pisum is elevated when aphids are reared on diets from which that eaa are omitted, demonstrating that buchnera scale eaa production to host demand. quantitative proteomics of bacteriocytes ... | 2014 | 25080346 |
| 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 |
| settling down: the genome of serratia symbiotica from the aphid cinara tujafilina zooms in on the process of accommodation to a cooperative intracellular life. | particularly interesting cases of mutualistic endosymbioses come from the establishment of co-obligate associations of more than one species of endosymbiotic bacteria. throughout symbiotic accommodation from a free-living bacterium, passing through a facultative stage and ending as an obligate intracellular one, the symbiont experiences massive genomic losses and phenotypic adjustments. here, we scrutinized the changes in the coevolution of serratia symbiotica and buchnera aphidicola endosymbion ... | 2014 | 24951564 |
| an ecological cost associated with protective symbionts of aphids. | beneficial symbioses are widespread and diverse in the functions they provide to the host ranging from nutrition to protection. however, these partnerships with symbionts can be costly for the host. such costs, so called "direct costs", arise from a trade-off between allocating resources to symbiosis and other functions such as reproduction or growth. ecological costs may also exist when symbiosis negatively affects the interactions between the host and other organisms in the environment. althou ... | 2014 | 24683464 |
| aphid facultative symbionts reduce survival of the predatory lady beetle hippodamia convergens. | non-essential facultative endosymbionts can provide their hosts with protection from parasites, pathogens, and predators. for example, two facultative bacterial symbionts of the pea aphid (acyrthosiphon pisum), serratia symbiotica and hamiltonella defensa, protect their hosts from parasitism by two species of parasitoid wasp. previous studies have not explored whether facultative symbionts also play a defensive role against predation in this system. we tested whether feeding on aphids harboring ... | 2014 | 24555501 |
| 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 |
| phenotypic effect of "candidatus rickettsiella viridis," a facultative symbiont of the pea aphid (acyrthosiphon pisum), and its interaction with a coexisting symbiont. | a gammaproteobacterial facultative symbiont of the genus rickettsiella was recently identified in the pea aphid, acyrthosiphon pisum. infection with this symbiont altered the color of the aphid body from red to green, potentially affecting the host's ecological characteristics, such as attractiveness to different natural enemies. in european populations of a. pisum, the majority of rickettsiella-infected aphids also harbor another facultative symbiont, of the genus hamiltonella. we investigated ... | 2014 | 24212575 |
| the combined effects of bacterial symbionts and aging on life history traits in the pea aphid, acyrthosiphon pisum. | while many endosymbionts have beneficial effects on hosts under specific ecological conditions, there can also be associated costs. in order to maximize their own fitness, hosts must facilitate symbiont persistence while preventing symbiont exploitation of resources, which may require tight regulation of symbiont populations. as a host ages, the ability to invest in such mechanisms may lessen or be traded off with demands of other life history traits, such as survival and reproduction. using the ... | 2014 | 24185857 |
| conditional reduction of predation risk associated with a facultative symbiont in an insect. | symbionts are widespread among eukaryotes and their impacts on the ecology and evolution of their hosts are meaningful. most insects harbour obligate and facultative symbiotic bacteria that can influence their phenotype. in the pea aphid acyrthosiphon pisum, an astounding symbiotic-mediated phenotype has been recently observed: when infected with the symbiotic bacteria rickettsiella viridis, young red aphid larvae become greener at adulthood and even darker green when co-infected with rickettsie ... | 2015 | 26618776 |
| a facultative endosymbiont in aphids can provide diverse ecological benefits. | ecologically important traits of insects are often affected by facultative bacterial endosymbionts. this is best studied in the pea aphid acyrthosiphon pisum, which is frequently infected by one or more of eight facultative symbiont species. many of these symbiont species have been shown to provide one ecological benefit, but we have little understanding of the range of effects that a single strain can have. here, we describe the phenotypes conferred by three strains of the recently discovered b ... | 2015 | 26206380 |
| 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 |
| heat stress affects facultative symbiont-mediated protection from a parasitoid wasp. | many insects carry facultative bacterial symbionts, which provide benefits including resistance to natural enemies and abiotic stresses. little is known about how these beneficial phenotypes are affected when biotic or abiotic threats occur simultaneously. the pea aphid (acyrthosiphon pisum) can host several well-characterized symbiont species. the symbiont known as x-type can protect against both parasitoid wasps and heat stress. here, we used three pea aphid genotypes that were naturally infec ... | 2016 | 27875577 |
| amino acid transporters implicated in endocytosis of buchnera during symbiont transmission in the pea aphid. | many insects host their obligate, maternally transmitted symbiotic bacteria in specialized cells called bacteriocytes. one of the best-studied insect nutritional endosymbioses is that of the aphid and its endosymbiont, buchnera aphidicola. aphids and buchnera are metabolically and developmentally integrated, but the molecular mechanisms underlying buchnera transmission and coordination with aphid development remain largely unknown. previous work using electron microscopy to study aphid asexual e ... | 2016 | 27895889 |
| 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 |
| symbionts modify interactions between insects and natural enemies in the field. | eukaryotes commonly host communities of heritable symbiotic bacteria, many of which are not essential for their hosts' survival and reproduction. there is laboratory evidence that these facultative symbionts can provide useful adaptations, such as increased resistance to natural enemies. however, we do not know how symbionts affect host fitness when the latter are subject to attack by a natural suite of parasites and pathogens. here, we test whether two protective symbionts, regiella insecticola ... | 2016 | 27561159 |
| seasonal changes in the endosymbiotic consortia of aphids from the genus cinara. | buchnera aphidicola is the primary endosymbiont of aphids with which it maintains an obligate mutualistic symbiotic relationship. insects also maintain facultative symbiotic relationships with secondary symbionts, and serratia symbiotica is the most common in aphids. the presence of both symbionts in aphids of the subfamily lachninae has been widely studied by our group. we examined two closely related aphids, cinara tujafilina and c. cedri in the present study. even though both b. aphidicola st ... | 2016 | 27297891 |
| 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 |
| direct flow cytometry measurements reveal a fine-tuning of symbiotic cell dynamics according to the host developmental needs in aphid symbiosis. | endosymbiotic associations constitute a driving force in the ecological and evolutionary diversification of metazoan organisms. little is known about whether and how symbiotic cells are coordinated according to host physiology. here, we use the nutritional symbiosis between the insect pest, acyrthosiphon pisum, and its obligate symbiont, buchnera aphidicola, as a model system. we have developed a novel approach for unculturable bacteria, based on flow cytometry, and used this method to estimate ... | 2016 | 26822159 |
| ontogenetic differences in localization of glutamine transporter apglnt1 in the pea aphid demonstrate that mechanisms of host/symbiont integration are not similar in the maternal versus embryonic bacteriome. | obligate intracellular symbionts of insects are metabolically and developmentally integrated with their hosts. typically, reproduction fails in many insect nutritional endosymbioses when host insects are cured of their bacterial symbionts, and yet remarkably little is known about the processes that developmentally integrate host and symbiont. here in the best studied insect obligate intracellular symbiosis, that of the pea aphid, acyrthosiphon pisum, with the gammaproteobacterium buchnera aphidi ... | 2016 | 26759710 |
| 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 |
| a genomic reappraisal of symbiotic function in the aphid/buchnera symbiosis: reduced transporter sets and variable membrane organisations. | buchnera aphidicola is an obligate symbiotic bacterium that sustains the physiology of aphids by complementing their exclusive phloem sap diet. in this study, we reappraised the transport function of different buchnera strains, from the aphids acyrthosiphon pisum, schizaphis graminum, baizongia pistaciae and cinara cedri, using the re-annotation of their transmembrane proteins coupled with an exploration of their metabolic networks. although metabolic analyses revealed high interdependencies bet ... | 2011 | 22229056 |
| comparative analysis of genome sequences from four strains of the buchnera aphidicola mp endosymbion of the green peach aphid, myzus persicae. | myzus persicae, the green peach aphid, is a polyphagous herbivore that feeds from hundreds of species of mostly dicot crop plants. like other phloem-feeding aphids, m. persicae rely on the endosymbiotic bacterium, buchnera aphidicola (buchnera mp), for biosynthesis of essential amino acids and other nutrients that are not sufficiently abundant in their phloem sap diet. tobacco-specialized m. persicae are typically red and somewhat distinct from other lineages of this species. to determine whethe ... | 2013 | 24365332 |
| 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 |