Publications

a srna in a reduced mutualistic symbiont genome regulates its own gene expression.	similar to other nutritional endosymbionts that are obligate for host survival, the mutualistic aphid endosymbiont, buchnera, has a highly reduced genome with few regulatory elements. until recently, it was thought that aphid hosts were primarily responsible for regulating their symbiotic relationship. however, we recently revealed that buchnera displays differential protein regulation, but not mrna expression. we also identified a number of conserved small rnas (srnas) that are expressed among ...	2017	29134727
a damping circadian clock drives weak oscillations in metabolism and locomotor activity of aphids (acyrthosiphon pisum).	timing seasonal events, like reproduction or diapause, is crucial for the survival of many species. global change causes phenologies worldwide to shift, which requires a mechanistic explanation of seasonal time measurement. day length (photoperiod) is a reliable indicator of winter arrival, but it remains unclear how exactly species measure day length. a reference for time of day could be provided by a circadian clock, by an hourglass clock, or, as some newer models suggest, by a damped circadia ...	2017	29097765
culture of an aphid heritable symbiont demonstrates its direct role in defence against parasitoids.	heritable symbionts are common in insects with many contributing to host defence. hamiltonella defensa is a facultative, bacterial symbiont of the pea aphid, acyrthosiphon pisum that provides protection against the endoparasitoid wasp aphidius ervi protection levels vary among strains of h. defensa that are differentially infected by bacteriophages named apses. by contrast, little is known about mechanism(s) of resistance owing to the intractability of host-restricted microbes for functional stu ...	2017	29093227
breakdown of a defensive symbiosis, but not endogenous defences, at elevated temperatures.	environmental factors, including temperature, can have large effects on species interactions, including mutualisms and antagonisms. most insect species are infected with heritable bacterial symbionts with many protecting their hosts from natural enemies. however, many symbionts or their products are thermally sensitive; hence, their effectiveness may vary across a range of temperatures. in the pea aphid, acyrthosiphon pisum, the bacterial symbiont hamiltonella defensa and its associated apse bac ...	2017	29087015
transcriptome profiling of neurosensory perception genes in wing tissue of two evolutionary distant insect orders: diptera (drosophila melanogaster) and hemiptera (acyrthosiphon pisum).	the neurogenesis and neuronal functions in insect wing have been understudied mainly due to technical hindrances that have prevented electrophysiology studies for decades. the reason is that the nano-architecture of the wing chemosensory bristles hampers the receptors accessibility of odorants/tastants to receptors in fixed setup, whereas in nature, the wing flapping mixes these molecules in bristle lymph. in this report, we analyzed the transcriptome of the wing tissue of two species phylogenet ...	2017	29075833
combined effects of night warming and light pollution on predator-prey interactions.	interactions between multiple anthropogenic environmental changes can drive non-additive effects in ecological systems, and the non-additive effects can in turn be amplified or dampened by spatial covariation among environmental changes. we investigated the combined effects of night-time warming and light pollution on pea aphids and two predatory ladybeetle species. as expected, neither night-time warming nor light pollution changed the suppression of aphids by the ladybeetle species that forage ...	2017	29021171
tetramorium tsushimae ants use methyl branched hydrocarbons of aphids for partner recognition.	in mutualisms, partner discrimination is often the most important challenge for interacting organisms. the interaction between ants and aphids is a model system for studying mutualisms; ants are provided with honeydew by aphids and, in turn, the ants offer beneficial services to the aphids. to establish and maintain this system, ants must discriminate mutualistic aphid species correctly. although recent studies have shown that ants recognize aphids as mutualistic partners based on their cuticula ...	2017	28980108
comparative gene mapping as a tool to understand the evolution of pest crop insect chromosomes.	the extent of the conservation of synteny and gene order in aphids has been previously investigated only by comparing a small subset of linkage groups between the pea aphid acyrthosiphon pisum and a few other aphid species. here we compared the localization of eight a. pisum scaffolds (covering more than 5 mb and 83 genes) in respect to the drosophila melanogaster muller elements identifying orthologous loci spanning all the four a. pisum chromosomes. comparison of the genetic maps revealed a co ...	2017	28880213
solid-phase microextraction-based cuticular hydrocarbon profiling for intraspecific delimitation in acyrthosiphon pisum.	insect cuticular hydrocarbons (chcs) play critical roles in reducing water loss and chemical communication. species-specific chc profiles have been used increasingly as an excellent character for species classification. however, considerably less is known about their potential for population delimitation within species. the aims of this study were to develop a solid-phase microextraction (spme)-based chc collection method and to investigate whether chc profiles could serve as potential chemotaxo ...	2017	28859151
expression differences in aphidius ervi (hymenoptera: braconidae) females reared on different aphid host species.	the molecular mechanisms that allow generalist parasitoids to exploit many, often very distinct hosts are practically unknown. the wasp aphidius ervi, a generalist koinobiont parasitoid of aphids, was introduced from europe into chile in the late 1970s to control agriculturally important aphid species. a recent study showed significant differences in host preference and host acceptance (infectivity) depending on the host a. ervi were reared on. in contrast, no genetic differentiation between a. ...	2017	28852588
orally delivered scorpion antimicrobial peptides exhibit activity against pea aphid (acyrthosiphon pisum) and its bacterial symbionts.	aphids are severe agricultural pests that damage crops by feeding on phloem sap and vectoring plant pathogens. chemical insecticides provide an important aphid control strategy, but alternative and sustainable control measures are required to avoid rapidly emerging resistance, environmental contamination, and the risk to humans and beneficial organisms. aphids are dependent on bacterial symbionts, which enable them to survive on phloem sap lacking essential nutrients, as well as conferring envir ...	2017	28837113
the chemical signatures underlying host plant discrimination by aphids.	the diversity of phytophagous insects is largely attributable to speciation involving shifts between host plants. these shifts are mediated by the close interaction between insects and plant metabolites. however, there has been limited progress in understanding the chemical signatures that underlie host preferences. we use the pea aphid (acyrthosiphon pisum) to address this problem. host-associated races of pea aphid discriminate between plant species in race-specific ways. we combined metabolom ...	2017	28819265
identification and functional characterization of an odorant receptor in pea aphid, acyrthosiphon pisum.	the sensitive olfactory system is necessary for survival of insects. odorant receptors (ors) are located on the dendrites of olfactory receptor neurons and play a critical role in odor detection. insect ors are functionally analyzed via heterologous expression in a xenopus oocyte system using a two-electrode voltage-clamp (tevc) electrophysiological recording. here, we have identified a novel or in the pea aphid, acyrthosiphon pisum, then we cloned and named it apisor4. we analyzed the apisor4 t ...	2017	28730637
morphological variation of aphidius ervi haliday (hymenoptera: braconidae) associated with different aphid hosts.	parasitoids are frequently used in biological control due to the fact that they are considered host specific and highly efficient at attacking their hosts. as they spend a significant part of their life cycle within their hosts, feeding habits and life history of their host can promote specialization via host-race formation (sequential radiation). the specialized host races from different hosts can vary morphologically, behaviorally and genetically. however, these variations are sometimes incons ...	2017	28713658
evidence of indirect symbiont conferred protection against the predatory lady beetle harmonia axyridis in the pea aphid.	defensive symbionts can provide significant fitness advantages to their hosts. facultative symbionts can protect several species of aphid from fungal pathogens, heat shock, and parasitism by parasitoid wasps. previous work found that two of these facultative symbionts can also indirectly protect pea aphids from predation by the lady beetle hippocampus convergens. when aphids reproduce asexually, there is extremely high relatedness among aphid clone-mates and often very limited dispersal. under t ...	2017	28693550
identification of the prothoracicotropic hormone (ptth) coding gene and localization of its site of expression in the pea aphid acyrthosiphon pisum.	insect hormones control essential aspects of physiology, behaviour and development in insects. the majority of insect hormones are peptide hormones that perform a highly diverse catalogue of functions. prothoracicotropic hormone (ptth) is a brain neuropeptide hormone whose main function is to stimulate the secretion of ecdysone (the moulting hormone) by the prothoracic glands in insect larvae thus playing a key role in the control of moulting and metamorphosis. moreover, both ptth release or blo ...	2017	28677913
diversity and evolution of mariner-like elements in aphid genomes.	although transposons have been identified in almost all organisms, genome-wide information on mariner elements in aphididae remains unknown. genomes of acyrthosiphon pisum, diuraphis noxia and myzus persicae belonging to the macrosiphini tribe, actually available in databases, have been investigated.	2017	28662628
dosage compensation and sex-specific epigenetic landscape of the x chromosome in the pea aphid.	heterogametic species display a differential number of sex chromosomes resulting in imbalanced transcription levels for these chromosomes between males and females. to correct this disequilibrium, dosage compensation mechanisms involving gene expression and chromatin accessibility regulations have emerged throughout evolution. in insects, these mechanisms have been extensively characterized only in drosophila but not in insects of agronomical importance. aphids are indeed major pests of a wide r ...	2017	28638443
transgenerational seasonal timer for suppression of sexual morph production in the pea aphid, acyrthosiphon pisum.	many aphid species switch reproductive modes seasonally, with the sexual generations appearing in autumn. sexual generations are induced by short days. it has been reported that the appearance of sexual morphs is suppressed by a transgenerational factor (a seasonal timer) over several generations after hatching from overwintered eggs. the present study examined whether the seasonal timer measures the number of days from hatching or the number of generations from hatching using the pea aphid, acy ...	2017	28610748
establishment and maintenance of aphid endosymbionts after horizontal transfer is dependent on host genotype.	animal-associated microbial communities have important effects on host phenotypes. individuals within and among species differ in the strains and species of microbes that they harbour, but how natural selection shapes the distribution and abundance of symbionts in natural populations is not well understood. symbionts can be beneficial in certain environments but also impose costs on their hosts. consequently, individuals that can or cannot associate with symbionts will be favoured under differen ...	2017	28566541
large-scale gene expression reveals different adaptations of hyalopterus persikonus to winter and summer host plants.	host alternation, an obligatory seasonal shifting between host plants of distant genetic relationship, has had significant consequences for the diversification and success of the superfamily of aphids. however, the underlying molecular mechanism remains unclear. in this study, the molecular mechanism of host alternation was explored through a large-scale gene expression analysis of the mealy aphid hyalopterus persikonus on winter and summer host plants. more than four times as many unigenes of t ...	2017	28547891
warming alters prey density and biological control in conventional and organic agricultural systems.	studies have shown that organically farmed fields promote natural predator populations and often have lower pest populations than conventional fields, due to a combination of increased predation pressure and greater plant resistance to pest damage. it is unknown how pest populations and predator efficacy may respond in these farming systems as global temperatures increase. to test these questions, we placed enclosures in eight alfalfa fields farmed using conventional (n = 4) or organic (n = 4) p ...	2017	28460041
apmicrodb: a microsatellite database of acyrthosiphon pisum.	pea aphids represent a complex genetic system that could be used for qtl analysis, genetic diversity and population genetics studies. here, we described the development of first microsatellite repeat database of the pea aphid (apmicrodb), accessible at "http://deepaklab.com/aphidmicrodb". we identified 3,40,233 ssrs using microsatellite (misa) tool that was distributed in 14,067 (out of 23,924) scaffold of the pea aphid. we observed 89.53% simple repeats of which 73.41% were mono-nucleotide, fol ...	2017	28413782
local and landscape drivers of predation services in urban gardens.	in agroecosystems, local and landscape features, as well as natural enemy abundance and richness, are significant predictors of predation services that may result in biological control of pests. despite the increasing importance of urban gardening for provisioning of food to urban populations, most urban gardeners suffer from high pest problems, and have little knowledge about how to manage their plots to increase biological control services. we examined the influence of local, garden scale (i.e ...	2017	28083983
genome of russian wheat aphid an economically important cereal aphid.	although the hemipterans (aphididae) are comprised of roughly 50,000 extant insect species, only four have sequenced genomes that are publically available, namely acyrthosiphon pisum (pea aphid), rhodnius prolixus (kissing bug), myzus persicae (green peach aphid) and diuraphis noxia (russian wheat aphid). as a significant proportion of agricultural pests are phloem feeding aphids, it is crucial for sustained global food security that a greater understanding of the genomic and molecular functioni ...	2017	29299110
microrna regulation in an ancient obligate endosymbiosis.	although many insects are associated with obligate bacterial endosymbionts, the mechanisms by which these host/endosymbiont associations are regulated remain mysterious. while micrornas (mirnas) have been recently identified as regulators of host/microbe interactions, including host/pathogen and host/facultative endosymbiont interactions, the role mirnas may play in mediating host/obligate endosymbiont interactions is virtually unknown. here, we identified conserved mirnas that potentially media ...	2017	29271121
context-dependent vertical transmission shapes strong endosymbiont community structure in the pea aphid, acyrthosiphon pisum.	animal-associated microbiomes are often comprised of structured, multispecies communities, with particular microbes showing trends of co-occurrence or exclusion. such structure suggests variable community stability, or variable costs and benefits-possibilities with implications for symbiont-driven host adaptation. in this study, we performed systematic screening for maternally transmitted, facultative endosymbionts of the pea aphid, acyrthosiphon pisum. sampling across six locales, with up to 5 ...	2017	29215202
characterisation, analysis of expression and localisation of the opsin gene repertoire from the perspective of photoperiodism in the aphid acyrthosiphon pisum.	organisms exhibit a wide range of seasonal responses as adaptions to predictable annual changes in their environment. these changes are originally caused by the effect of the earth's cycles around the sun and its axial tilt. examples of seasonal responses include floration, migration, reproduction and diapause. in temperate climate zones, the most robust variable to predict seasons is the length of the day (i.e. the photoperiod). the first step to trigger photoperiodic driven responses involves ...	2018	29203177
a small set of differentially expressed genes was associated with two color morphs in natural populations of the pea aphid acyrthosiphon pisum.	color polymorphism is an ecologically important trait, which is related to local adaptation and ecological speciation. the pea aphid acyrthosiphon pisum shows color polymorphism: the red and green color morphs where differences in ecological adaptation have been observed. here, we measured genome-wide gene expression profiles of two color morphs in natural populations of a. pisum to explore the genetic basis of differentiated ecological adaptation. the results showed that only 32 genes were sign ...	2018	29378241
disentangling the causes for faster-x evolution in aphids.	the faster evolution of x chromosomes has been documented in several species, and results from the increased efficiency of selection on recessive alleles in hemizygous males and/or from increased drift due to the smaller effective population size of x chromosomes. aphids are excellent models for evaluating the importance of selection in faster-x evolution because their peculiar life cycle and unusual inheritance of sex chromosomes should generally lead to equivalent effective population sizes fo ...	2018	29360959
comparative genomics analysis of triatomines reveals common first line and inducible immunity-related genes and the absence of imd canonical components among hemimetabolous arthropods.	insects operate complex humoral and cellular immune strategies to fend against invading microorganisms. the majority of these have been characterized in drosophila and other dipterans. information on hemipterans, including triatominae vectors of chagas disease remains incomplete and fractionated.	2018	29357911
comparative proteomics studies of insect cuticle by tandem mass spectrometry: application of a novel proteomics approach to the pea aphid cuticular proteins.	the exoskeleton of arthropods, called cuticle, is a biological composite material consisting principally of n-acetylglucosamine polymer embedded in cuticular proteins (cps). the cps have been studied and characterized by mass spectrometry in several cuticular structures and in many arthropods. such analyses were usually carried out by protein extraction using sds detergent followed by electrophoresis, allowing detection and identification of a large number of cps. to build a repertoire of cuticu ...	2018	29327416