Discipline: Biological Sciences
Subcategory: Plant Research
Session: 2
Room: Exhibit Hall
Joseph M Outar - University of Missouri - Columbia
Co-Author(s): Katie Horton, University of Missouri - Columbia, Columbia, MOLeland Cseke, University of Missouri - Columbia, Columbia, MOWalter Gassmann, University of Missouri - Columbia, Columbia, MO
In nature it is rare that a plant interacts with just one bacterial pathogen, much less one single bacterial effector protein. Plants have developed an immune system that can combat pathogens, with one of its major components being its resistance proteins. These resistance proteins are immune receptors that are capable of recognizing the pathogen-derived effector proteins that pathogens inject into the plant’s cells. We are developing a new experimental model system consisting of using multiple effectors to more accurately represent the natural environment that farmers would face regularly. Currently our lab studies the bacterial effector AvrRps4, which was isolated from Pseudomonas syringae pv pisi, and its behavior after being infiltrated into lettuce, but its effects on recognition of other effectors that have also been infiltrated has not been characterized. We are also studying XopQ which is an effector produced by the bacterium Xanthomonas campestris pv. vesicatoria (Xcv) which is the cause of bacterial spot disease of plants within Solanaceae, including tobacco (Nicotiana tabacum). Previous research has shown that XopQ is recognized in tobacco via the same signaling pathway that we hypothesize AvrRps4 interrupts. As both bacteria are pathogenic for both lettuce and tobacco, we have chosen to co-infiltrate AvrRps4 with XopQ into both plants to test this hypothesis. Cloning XopQ into the expression vector pHM1, which is known for its genetically stable replication and delivery efficiency, is required for our purposes in this experiment. This process allows us to take the full-length genome of Xcv and amplify by PCR the piece that encodes XopQ so that we can place it in pHM1 which will then express XopQ when infiltrated. Co-infiltration occurs when this vector along with a vector that codes for AvrRps4 are both infiltrated into the same plant at the same time. Preliminary results show that XopQ has been ligated into our chosen vector of pHM1 and cloning has been successful. We expect to see a reduction in XopQ recognition from the plant’s normal response when AvrRps4 is present to inhibit the recognition. This research will allow us to have a clearer understanding of how bacterial pathogen-derived effectors are recognized by plants when multiple effectors are present and the effect that could have on the wider crop industry when protecting their plants from disease.
Funder Acknowledgement(s): MARC/IMSD
Faculty Advisor: Walter Gassmann, gassmannw@missouri.edu
Role: I have done the vast majority of the experiments in this project with some oversight from Katie Horton and Leland Cseke. I have also planned out the steps and the time line independently as well.