CSB452 LECTURE 3 ETI Gene for Gene Resistance Plant R-protein recognizes specific bacterial Avr protein, which lead to HR. TTSE = Hop and block HR. Many R proteins are CCTIR-NB-LRR, Kinase or TF. May be membrane bound. Compatible = virulent, unrecognizable by plant defence = susceptible, diseased plant. Incompatible = avirulent, recognizable by plant defence = resistant plant. Resistance is a dominant trait. Different soybean cultivars recognize different TTSE: Merit recognizes AvrB, not AvrRpm1, as AvrB- grows better. Flambeau recognizes AvrRpm1 but not AvrB as AvrRpm1- grows better. Both AvrB and AvrRpm1 recognition is mapped to Rpg1 locus containing Rpm1 protein. Rpm1-null plant has no HR and later die of disease. Lock model: R protein is receptor and TTSE is ligand, only 2 examples. AvrPita: Pita and Avr9: Cf9. RPM1 Interacting Protein (RIN4) Guard model: R protein monitor TTSE target by directly binding to targets. RIN4 is targeted by both AvrB and AvrRpm1 and bound by R protein RPM1 and is necessary for recognition of AvrB and AvrRpm1 by RPM1 as in rin4 KD there is no HR.