Pathogen conservation molecules and PAMP-triggered innate immunity in plants

Abstract:

Pathogen associated molecular patterns (PAMPs) recognized by host cell surface localized pattern-recognition receptors (PRRs) are pathogen conservation molecules. So far, a few pairs of characterized PRR/PAMP in plants provided useful models to study the specificity of ligand-binding and likely activation mechanisms. For example, recognition models of FLS2-flagellin, EFR-Tu (EF-Tu), CEBiP/CERK1-chitin and XA21-Ax21 have been extensively studied. The perception between PRR and PAMP triggers immune response (PTI) to resist pathogens. However, to successfully grow and proliferate on their hosts, virulent pathogens had to override the PTI, for which, these pathogens evolved a variety of strategies, such as injecting effector proteins into the plant cell or sequestering their PAMPs. Based on the knowledge on the interaction of PRR-PAMP, researchers are trying to engineer PRRs ( chimeras of PRRs) to develop new strategies in molecular breeding for achieving durability and a broad-spectrum disease resistance. We reviewed the recent findings about recognitions of PRRs-PAMPs, the engineered PRRs, and discussed the future prospects and several issues in researches on PTI.