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Genome sequence of the pea aphid Acyrthosiphon pisum

PLoS Biology (Impact Factor: 12.69). 02/2010; 8(2):e1000313.

ABSTRACT Aphids are important agricultural pests and also biological models for studies of insect-plant interactions, symbiosis, virus vectoring, and the developmental causes of extreme phenotypic plasticity. Here we present the 464 Mb draft genome assembly of the pea aphid Acyrthosiphon pisum. This first published whole genome sequence of a basal hemimetabolous insect provides an outgroup to the multiple published genomes of holometabolous insects. Pea aphids are host-plant specialists, they can reproduce both sexually and asexually, and they have coevolved with an obligate bacterial symbiont. Here we highlight findings from whole genome analysis that may be related to these unusual biological features. These findings include discovery of extensive gene duplication in more than 2000 gene families as well as loss of evolutionarily conserved genes. Gene family expansions relative to other published genomes include genes involved in chromatin modification, miRNA synthesis, and sugar transport. Gene losses include genes central to the IMD immune pathway, selenoprotein utilization, purine salvage, and the entire urea cycle. The pea aphid genome reveals that only a limited number of genes have been acquired from bacteria; thus the reduced gene count of Buchnera does not reflect gene transfer to the host genome. The inventory of metabolic genes in the pea aphid genome suggests that there is extensive metabolite exchange between the aphid and Buchnera, including sharing of amino acid biosynthesis between the aphid and Buchnera. The pea aphid genome provides a foundation for post-genomic studies of fundamental biological questions and applied agricultural problems.

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Available from: Vicente Perez-Brocal, Jul 14, 2015
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    • "Interestingly, the 525 Mb genome of A. pisum has recently been sequenced by the International Aphid Genomic Consortium providing a resource for comparative genomics and the tools to identify targets for control (AphidBase; http://www.aphidbase.com; [35]). We identified the sequences of the two native PKs as SPPYSPPFSPRL-NH 2 and GGTTQSSNGIWFGPRL-NH 2 , as well as related PRLamide peptides QAVMAQPQVPRL-NH 2 and pQAVMAQPQVPRL-NH 2 . "
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    ABSTRACT: The pyrokinins (PK) are multifunctional neuropeptides found in a variety of arthropod species, including the pea aphid Acyrthosiphon pisum (Hemiptera: Aphidae). A series of biostable pyrokinin analogs based on the shared C-terminal pentapeptide core region were fed in solutions of artificial diet to the pea aphid over a period of three days and evaluated for antifeedant and aphicidal activity. The analogs contained either modified Pro residues Oic or Hyp and or a d-amino acid in key positions to enhance resistance to tissue-bound peptidases and retain activity in a number of PK bioassays. A series of PK analogs conjugated with two lengths of polyethyleneglycol (PEG) polymers were also evaluated in the aphid feeding assay. Three of the biostable PK analogs demonstrated potent antifeedant activity, with a marked reduction in honeydew formation and very high mortality after 1 day. In contrast, a number of unmodified, natural pyrokinins and several other analogs containing some of the same structural components that promote biostability were inactive. Two of the most active analogs, Oic analog PK-Oic-1 (FT[Oic]RL-NH2) and PEGylated analog PK-dF-PEG8 [(P8)-YF[dF]PRL-NH2], featured aphicidal activity calculated at LC50's of 0.042 nmol/μl [0.029 μg/μl] (LT50 of 1.0 day) and 0.126 nmol/μl (LT50 of 1.3 days), respectively, matching the potency of some commercially available aphicides. Notably, a PEGylated analog of a PK antagonist can block over 55% of the aphicidal effects of the potent PK agonist PK-Oic-1, suggesting that the aphicidal effects are mediated by a PK receptor. The mechanism of this activity has yet to be established, though the aphicidal activity of the biostable analogs may result from disruption of digestive processes by interfering with gut motility patterns, a process shown to be regulated by the PKs in other insects. The active PK analogs represent potential leads in the development of selective, environmentally friendly aphid pest control agents.
    Peptides 11/2011; 34(1):266-73. DOI:10.1016/j.peptides.2011.11.009 · 2.61 Impact Factor
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    • "Interestingly, the 525 Mb genome of A. pisum has recently been sequenced by the International Aphid Genomic Consortium providing a resource for comparative genomics and the tools to identify targets for control (AphidBase; http://www.aphidbase.com; [35]). We identified the sequences of the two native PKs as SPPYSPPFSPRL-NH 2 and GGTTQSSNGIWFGPRL-NH 2 , as well as related PRLamide peptides QAVMAQPQVPRL-NH 2 and pQAVMAQPQVPRL-NH 2 . "
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    ABSTRACT: Peptides j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / p e p t i d e s Biostable and PEG polymer-conjugated insect pyrokinin analogs demonstrate antifeedant activity and induce high mortality in the pea aphid Acyrthosiphon pisum (Hemiptera: Aphidae) a b s t r a c t The pyrokinins (PK) are multifunctional neuropeptides found in a variety of arthropod species, including the pea aphid Acyrthosiphon pisum (Hemiptera: Aphidae). A series of biostable pyrokinin analogs based on the shared C-terminal pentapeptide core region were fed in solutions of artificial diet to the pea aphid over a period of three days and evaluated for antifeedant and aphicidal activity. The analogs contained either modified Pro residues Oic or Hyp and or a d-amino acid in key positions to enhance resistance to tissue-bound peptidases and retain activity in a number of PK bioassays. A series of PK analogs conjugated with two lengths of polyethyleneglycol (PEG) polymers were also evaluated in the aphid feeding assay. Three of the biostable PK analogs demonstrated potent antifeedant activity, with a marked reduction in honeydew formation and very high mortality after 1 day. In contrast, a number of unmodified, natural pyrokinins and several other analogs containing some of the same structural components that promote biostability were inactive. Two of the most active analogs, Oic analog PK-Oic-1 (FT[Oic]RL-NH 2) and PEGylated analog PK-dF-PEG 8 [(P 8)-YF[dF]PRL-NH 2 ], featured aphicidal activity calculated at LC 50 's of 0.042 nmol/l [0.029 g/l] (LT 50 of 1.0 day) and 0.126 nmol/l (LT 50 of 1.3 days), respectively, matching the potency of some commercially available aphicides. Notably, a PEGylated analog of a PK antagonist can block over 55% of the aphicidal effects of the potent PK agonist PK-Oic-1, suggesting that the aphicidal effects are mediated by a PK receptor. The mechanism of this activity has yet to be established, though the aphicidal activity of the biostable analogs may result from disruption of digestive processes by interfering with gut motility patterns, a process shown to be regulated by the PKs in other insects. The active PK analogs represent potential leads in the development of selective, environmentally friendly aphid pest control agents.
    Peptides 11/2011; 34:266-273. · 2.61 Impact Factor
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