Project description:The complete mitochondrial genome of the strawberry aphid Chaetosiphon fragaefolii Cockerell, 1901 (Hemiptera: Aphididae) from California, USA
Project description:The aphid Chaetosiphon fragaefolii Cockerell, 1901 is an agricultural pest and known vector of strawberry viruses. To better understand its biology and systematics, we performed a genomic analysis on C. fragaefolii collected from Quinalt strawberry plants from Pacific Grove, Monterey county, California, USA using Oxford Nanopore and Illumina sequencing. The resulting data were used to assemble the aphids complete mitogenome. The mitogenome of C. fragaefolii is 16,108 bp in length and contains 2 rRNA, 13 protein-coding, and 22 tRNA genes (GenBank accession number LC590896). The mitogenome is similar in content and organization to other Aphididae. Phylogenetic analysis of the C. fragaefolii mitogenome resolved it in a fully supported clade in the tribe Macrosiphini. Analysis of the cox1 barcode sequence of C. fragaefolii from California found exact and nearly identical sequences to C. fragaefolii and Chaetosiphon thomasi Hille Ris Lambers, 1953, suggesting the two species are conspecific.
Project description:Myzus persicae (green peach aphid) feeding on Arabidopsis thaliana induces a defense response, quantified as reduced aphid progeny production, in infested leaves but not in other parts of the plant. Similarly, infiltration of aphid saliva into Arabidopsis leaves causes only a local increase in aphid resistance. Further characterization of the defense-eliciting salivary components indicates that Arabidopsis recognizes a proteinaceous elicitor with a size between 3 to 10 kD. Genetic analysis using well-characterized Arabidopsis mutant shows that saliva-induced resistance against M. persicae is independent of the known defense signaling pathways involving salicylic acid, jasmonate, and ethylene. Among 78 Arabidopsis genes that were induced by aphid saliva infiltration, 52 had been identified previously as aphid-induced, but few are responsive to the well-known plant defense signaling molecules salicylic acid and jasmonate. Quantitative PCR analysis confirms expression of saliva-induced genes. In particular, expression of a set of O-methyltransferases, which may be involved in the synthesis of aphid-repellent glucosinolates, was significantly up-regulated by both M. persicae feeding and treatment with aphid saliva. However, this did not correlate with increased production of 4-methoxyindol-3-ylmethylglucosinolate, suggesting that aphid salivary components trigger an Arabidopsis defense response that is independent of this aphid-deterrent glucosinolate.
Project description:Bioinformatic prediction, deep sequencing of microRNA and expression analysis during phenotypic plasticity in the pea aphid acyrthosiphon pisum We developed high throughput Solexa sequencing and bioinformatic analyses of the genome of the pea aphid Acyrthosiphon pisum in order to identify the first miRNAs from a hemipteran insect. By combining these methods we identified 155 miRNAs including 56 conserved and 99 new miRNAs. Moreover, we investigated the regulation of these miRNAs in different alternative morphs of the pea aphid by analysing the expression of miRNAs across the switch of reproduction mode.