Date of Award


Degree Name

Master of Science


Biological Sciences

First Advisor

Dr. Jian Yao

Second Advisor

Dr. Yan Lu

Third Advisor

Dr. Todd Barkman


Plant, pathology, signaling, salicylate, jasmonate

Access Setting

Masters Thesis-Open Access


The jasmonic (JA) and salicylic acid (SA) signaling systems regulate diverse plant developmental processes and immune responses. Due to the opposite end-goals of various pathogen-response pathways, a certain level of antagonism between the JA and SA pathways is required. However, over-suppression of any single pathway would leave a plant susceptible to invasion by a specific class of pathogen. We investigate the regulation of crosstalk between the JA- and SA-mediated immune pathways and how the dilemma of specific susceptibility may be avoided. Manipulation of Arabidopsis thaliana genotypes was utilized to determine the effects of protein knockout on pathogen-specific susceptibility and resistance. The effects of hormone treatment on protein concentration and the effects of protein knockout on the plant transcriptome were investigated as well. Loss of the plant U-box protein 25/26 increased susceptibility of plants to necrotrophic pathogen Pectobacterium carotovorum, indicating that this protein is instrumental in regulation of immune pathways required for optimization of fitness.