Characterization of the flagellin-derived MAMP flgII-28 and its perception in various cultivars of tomato
In Pattern-Triggered Immunity (PTI), plants use pattern recognition receptors (PRRs) to detect evolutionarily conserved microbe-associated molecular patterns (MAMPs). Flagellin Sensing 3 (FLS3) is a PRR that has recently been identified by the Martin Lab. FLS3 has been shown to recognize the 28 amino acid flagellin epitope flgII-28 of PstDC3000, a model strain of Pseudomonas syringae pv. tomato.Pseudomonas syringae pv. tomato is the causative agent of bacterial speck disease. P. syringae pvmaculicola ES4326 (PmaES4326) is a taxonomically related phytopathogenic virulent strain of P. syringae.It has been hypothesized that mutations in the amino acid sequence of flgII-28 as well as another flagellin epitope, flg22 in Pma may render the flagellin non-recognizable, allowing it to evade PTI
Plant perception of MAMPs induces the generation of reactive oxygen species (ROS). To assess the response of various tomato cultivars to flg22 and flgII-28 peptides from PstDC3000 and PmaES4326 strains, (ROS) assays were performed. Additionally, these cultivars were inoculated with five syntheticPstDC3000 strains using vacuum infiltration methods in order to determine whether they could perceive flg22 or flgII-28from PmaES4326in the context of a pathogen infection. Demonstrating that a tomato cultivar is responsive to flgII-28 from PmaES4326in the context of a pathogen infection would indicate that FLS3 is able to perceive alternative sequences of flgII-28. Broadening of specificity of flagellin perception could prove useful in conferring resistance to a wider variety of pathogens with different flagellin sequences in other solanaceous species.
My PGRP internship has allowed me to build upon my past research experiences and be immersed in exploration of the plant sciences. It enabled me to pinpoint the field to specialize in during graduate school.. I am grateful to Dr. Greg Martin for inviting me to work in his lab, to my mentor Sarah Hind for her constant guidance and support, and to all of the other lab members who were incredibly welcoming and always willing to offer their help.