4 research outputs found
Predicted Effector Molecules in the Salivary Secretome of the Pea Aphid (Acyrthosiphon pisum): A Dual Transcriptomic/Proteomic Approach
The relationship between aphids and their host plants is thought to be functionally
analogous to plant-pathogen interactions. Although virulence effector proteins that
mediate plant defenses are well-characterized for pathogens such as bacteria, oomycetes, and
nematodes, equivalent molecules in aphids and other phloem-feeders are poorly understood.
A dual transcriptomic-proteomic approach was adopted to generate a catalog of candidate
effector proteins from the salivary glands of the pea aphid, Acyrthosiphon pisum. Of the 1557
transcript supported and 925 mass spectrometry identified proteins, over 300 proteins were
identified with secretion signals, including proteins that had previously been identified
directly from the secreted saliva. Almost half of the identified proteins have no homologue
outside aphids and are of unknown function. Many of the genes encoding the putative
effector proteins appear to be evolving at a faster rate than homologues in other insects, and
there is strong evidence that genes with multiple copies in the genome are under positive
selection. Many of the candidate aphid effector proteins were previously characterized in
typical phytopathogenic organisms (e.g., nematodes and fungi) and our results highlight
remarkable similarities in the saliva from plant-feeding nematodes and aphids that may indicate the evolution of common solutions
to the plant-parasitic lifestyle