Dissect the Timing Mechanism for Immune Maturation in Plants

项目总结

PROJECT SUMMARY The maturation of an organism is associated with changes in a spectrum of physiological and morphological traits, including age-dependent change of immunity. Plants undergo an age- dependent gain of disease resistance during shoot maturation, which is known as the Age-related resistance (ARR). Despite the accumulating knowledge of the molecular and cellular details of the plant innate immune network, our knowledge about how the defense responses are incorporate into distinct cellular context during the maturation of an organism is still very limited. The aim of this proposed study is to dissect the timing mechanism that governs the onset of ARR in plants. We will use Arabidopsis thaliana and its bacterial pathogen Pseudomonas syringae pv. tomato DC3000 as a model system to elucidate the genetic architecture and signaling components of ARR. Our overall hypothesis is that a heterochronic microRNA pathway is an intrinsic clock regulating the coordinated onset of developmental and immune maturation. Functional diversification of the miRNA targets ensures the robustness and plasticity of the maturation process in response to intrinsic and environmental signals. We aim to identify the genetic components linking developmental timing and innate immunity. We will also explore the host-pathogen arms race on the components of ARR. The plant innate immune system share striking similarities with the mammalian innate immune system in receptor structure and signaling cascade. The proposed study has promising potential to generate novel insights into the molecular mechanisms of how developmental and immune programs are coordinated during the maturation of an organism. Our long-term goal is to provide fundamental knowledge of the crosstalk between development and defense, a tradeoff critical for plant survival.