Project description:Aphids, sap-sucking insects in the order Hemiptera, are among the most prolific insect vectors of plant viruses Plant viruses from the family Luteoviridae are transmitted exclusively by aphids in a circulative manner and cause significant crop yield losses. Circulative plant viruses must cross the aphid gut and other tissues prior to transmission to a new host plant. The discovery of proteins that control acquisition and transmission in the insect vector is the biggest challenge for the vector biology field and will have practical applications for growers by providing new molecular targets for the development of precision vector management tools. The green peach aphid, Myzus persicae, is a vector of the Potato leafroll virus (PLRV), a polerovirus in the Luteoviridae. PLRV transmission efficiency was significantly reduced when a clonal lineage of M. persicae was reared on turnip (T-Myzus) as compared to the weed physalis (P-Myzus). The effect on PLRV transmission efficiency was transient and caused by a host-switch response. Using 2-D DIGE, we revealed that the major difference in the proteome profile of P- and T-Myzus was the lysosomal cysteine protease cathepsin B, with multiple size and charge isoforms of this enzyme up-regulated in T-Myzus. Quantitative, shotgun proteomics revealed a specific upregulation in the expression of other lysosomal proteins in T-Myzus as compared to P-Myzus, including cathepsin B, cathepsin B-16, beta-glucuronidase, peroxidasin, legumain-like, and aminopeptidase-N. The titer of PLRV was over 1.5 fold higher in P-Myzus than in T-Myzus at 24h and 72h after the beginning of virus acquisition, suggesting that virus acquisition in P-Myzus was more efficient. Cathepsin B and PLRV localization were starkly different in P- and T-Myzus midguts, the site of PLRV acquisition into the insect. In P-Myzus midguts, an abundance of PLRV was observed inside midgut cells, and cathepsin B was sequestered in a subcellular compartment. In contrast, there is near complete co-localization of cathepsin B and PLRV at the cell membranes in viruliferous T-Myzus. Inhibition of cathepsin and other cysteine proteases with E64 restored the ability of T-Myzus to transmit PLRV in a dose-dependent manner, suggesting that the activities of lysosomal cysteine proteases at the cell membrane in T-Myzus is responsible for the change in virus transmission phenotype in these aphids. T-Myzus individuals weighed more and had more progeny than P-Myzus individuals. These data are all consistent with the hypothesis that there is an induction of lysosomal exocytos in the midgut of T-Myzus linked to the ability of the aphid to acquire PLRV. These data also show that the ability of the generalist aphid M. persicae to transmit PLRV is influenced by the host plant the aphids are reared on, information that is useful to growers for polerovirus management in field crops.
Project description:This SuperSeries is composed of the following subset Series: GSE18657: Response to nicotine (100 µM) in heads of the tobacco aphid Myzus persicae GSE18658: Response to nicotine (250 µM) in heads of the tobacco aphid Myzus persicae Refer to individual Series
Project description:The aim of this experiment was to compare the transciptome of the peach-potato aphid (Myzus persicae) clone 4106a (a laboratory insecticide-susceptible standard collected from potato in Scotland in 2000) with clone FRC (an insecticide resistant aphid clone collected from peach in France in 2009) to identify which genes are over or underexpressed in the resistant phenotype. The custom microarray used in this study was designed using the Agilent eArray platform (Agilent Technologies) by the Georg Jander Lab and is based on a previously described array containing probes for >10, 000 M. persicae unigenes produced by Sanger sequencing (Ramsey, Wilson et al. 2007) augmented with an additional 30, 517 probe set designed on EST unigene sequences identified in a 454 sequencing project (Ramsey, Rider et al. 2010). The final slide layout consists of four arrays of 45, 220 60-mer probes and these are produced by Agilent by in situ oligonucleotide synthesis. References: Ramsey, J. S., D. S. Rider, et al. (2010). "Comparative analysis of detoxification enzymes in Acyrthosiphon pisum and Myzus persicae." Insect Molecular Biology 19: 155-164. Ramsey, J. S., A. C. C. Wilson, et al. (2007). "Genomic resources for Myzus persicae: EST sequencing, SNP identification, and microarray design." BMC Genomics 8.
Project description:The aim of this experiment was to compare the transciptome of the peach-potato aphid (Myzus persicae) clone 4106a (a laboratory insecticide-susceptible standard collected from potato in Scotland in 2000) with clone FRC (an insecticide resistant aphid clone collected from peach in France in 2009) to identify which genes are over or underexpressed in the resistant phenotype. The custom microarray used in this study was designed using the Agilent eArray platform (Agilent Technologies) by the Georg Jander Lab and is based on a previously described array containing probes for >10, 000 M. persicae unigenes produced by Sanger sequencing (Ramsey, Wilson et al. 2007) augmented with an additional 30, 517 probe set designed on EST unigene sequences identified in a 454 sequencing project (Ramsey, Rider et al. 2010). The final slide layout consists of four arrays of 45, 220 60-mer probes and these are produced by Agilent by in situ oligonucleotide synthesis. References: Ramsey, J. S., D. S. Rider, et al. (2010). "Comparative analysis of detoxification enzymes in Acyrthosiphon pisum and Myzus persicae." Insect Molecular Biology 19: 155-164. Ramsey, J. S., A. C. C. Wilson, et al. (2007). "Genomic resources for Myzus persicae: EST sequencing, SNP identification, and microarray design." BMC Genomics 8. Two-condition experiment, 4106a vs. FRC Myzus persicae clones. Biological replicates: 4 pools of RNA extracted from ten 15 day old aphids of each clone. Technical Replicates: Two technical reps incorporating a dye swap. Total replication: eight replicates for each clone.
Project description:Aphids are phloem-feeding insects that cause yield loss on a wide range of crops, including cereals such as barley. While most aphid species are limited to one or few host species, some are able to reproduce on many plants belonging to different families. Interestingly, aphid probing-behaviour can be observed on both host and non-host species indicating that interactions take place at the molecular level that may impact host range. Here, we aimed to gain insight into the interaction of barley with aphid species differing in their ability to infest this crop by analysing transcriptional responses. First, we determined colonization efficiency, settlement, and probing behaviour for the aphid species Rhopalosiphum padi, Myzus persicae and Myzus cerasi, which defined host, poor-host and non-host interactions, respectively. Analyses of barley transcriptional responses revealed gene sets differentially regulated upon the different barley-aphid interactions and showed that the poor-host interaction with M. persicae resulted in the strongest deregulation of genes. Interestingly, we identified several thionin genes strongly up-regulated upon interaction with M. persicae, and to a lesser extend upon R. padi interaction. Ectopic expression of two of these genes in Nicotiana benthamiana reduced host susceptibility to M. persicae, indicating thionins contribute to defences against aphids.
Project description:The aim of this experiment was to compare the transciptome of the peach-potato aphid (Myzus persicae) clone 4106a (a laboratory insecticide-susceptible standard collected from potato in Scotland in 2000) with clone 5191A (an insecticide resistant aphid clone collected from tobacco in Greece in 2007) to identify which genes are over or underexpressed in the resistant phenotype. Two-condition experiment, 4106a vs. 5191a Myzus persicae clones. Biological replicates: 4 pools of RNA extracted from ten 15 day old aphids of each clone. Technical Replicates: Two technical reps incorporating a dye swap. Total replication: eight replicates for each clone.