Aphids feed on the plant with specialized piercing-sucking mouthparts in which they ingest sap and spit a complex mixture of saliva that aids them in feeding. The saliva is known to contain an abundance of proteins that can dampen plant defenses and alter plant physiology. However, aphid saliva has also been found to contain a rich diversity of small molecules (i.e. metabolites), including citric acid cycle intermediates. The purpose of this work was to discover the role of these metabolites in the plant-aphid interaction. By feeding aphids with stable isotope carbon (13C), aphid salivary metabolites were identified in plants after aphid feeding. Plant metabolite accumulation is altered by aphid feeding and many plant metabolites contain 13C, indicating salivary metabolites are incorporated into plant metabolism. Additionally, metabolic flux in infested and uninfested plants using aphids with 13C labeled salivary metabolites was used to determine altered metabolic pathways that could be beneficial to aphid fitness on the plant. Overall, these results demonstrate that aphid saliva is even more complex than originally known and diversely functions to manipulate the plant-aphid interaction.
.png)
