“Looking deeper into the Pto/Prf disease resistance signaling pathway in tomato”
The bacterial pathogen Pseudomonas syringae pv. tomato (Pst) causes bacterial speck disease in tomato, leaving the plant either unable to survive or the fruits unsellable due to necrotic lesions. A better understanding of the tomato-Pst interaction can contribute to the field of agriculture with cross organismal applications in bacterial pathogenesis and plant immunity, as well as develop new tomato cultivars with enhanced resistance to Pst and other pathogens. Effector-triggered immunity (ETI) is the second layer of plant immunity against pathogen infection. I investigated the role of the helper NLRs (nucleotide-binding leucine-rich repeats), the Nrc (NLR required for cell death) genes, in the Pto/Prf-mediated ETI pathway. The Martin Lab has developed multiple nrc knockout mutants using the CRISPR/Cas9 technology. The nrc mutants were vacuum inoculated with various Pst strains and the nrc2/3 double knockout completely lost resistance to the Pst DC3000 strain, while the single knockout of nrc2 or nrc3 showed similar resistance compared to the wild-type plants. This indicates Nrc2 and Nrc3 together play an important role in ETI. To investigate where Nrc2/3 act in the Pto/Prf pathway, I agroinfiltrated multiple autoactive proteins in the nrc2/3 mutants and the wildtype plants. The Pto and Prf autoactive proteins did not elicit cell death in the nrc2/3 double mutant, but the M3Ka and MKK2 autoactive proteins still elicited cell death in the absence of Nrc2/3, indicating Nrc2/3 plays a role upstream of the MAPK cascade in the Pto/Prf signaling pathway.
My PGRP intern experience at the Boyce Thompson Institute was incredible. Working with my mentor, I was able to learn several new lab and interpersonal skills that I will carry with me for the rest of my career. Throughout this program, I began to increase my self-identity as a scientist, and my confidence in a lab setting has dramatically improved. I was able to be exposed to plant biology technologies and concepts that were not available to me before, and I enter the rest of my collegiate career with excitement and hope. I believe my time in the Martin Lab has been invaluable and the relationships I made in the program will also last me a lifetime. I am eternally grateful for this opportunity, and I look forward to continuing my career as a plant scientist.