Time: Tuesday 12:30-1:30 Pm  February 19 ^th

 

Title: Signal integration in and intracellular dynamics of the plant immune system 

 

Speaker: Paul Schulze-Lefert, Ph.D

Director and Professor Department of Plant Microbe Interactions The Max-Planck-Institut für Züchtungsforschung (MPIZ), Cologne

 

Host: Jian-Min Zhou, Ph.D

 

Location： Auditorium（北京生命科学研究所一楼学术报告厅）

 

Abstract:

We study fundamental molecular processes underlying interactions between plants and pathogens. Plants and animals have evolved structurally related innate immune sensors inside cells to detect the presence of microbial molecules. An evolutionary ancient folding machinery becomes engaged for the synthesis of autorepressed receptor forms in both kingdoms. The receptors act as regulatory signal transduction switches and are activated upon direct or indirect perception of non-self structures. Our findings indicate that nucleo-cytoplasmic partitioning and nuclear activity is critical for the function of plant immune sensors that trigger disease resistance responses to widespread ascomycete fungal parasites. The activated immune sensor directly associates with WRKY transcriptional repressors and interferes with their activity, thereby linking receptor function totranscriptional reprogramming of host cells for pathogen defence. Plant cells assemble a pathogen-inducible machinery at the cell surface that shares several features with the immunological synapse, a specialized junction between a T cell and a target cell in animals. This enables in plants and animals execution of immune responses through focal secretion. Common mechanisms include co-stimulatory non-self/alarm signals as triggers, cell polarization driven by actin cytoskeleton remodeling, protein concentration into ring-shaped assemblies at the cell periphery, and focal SNARE protein-mediated exocytosis. Whilst in plants execution of immune responses by polar secretion appears to be a cell-type independent property, its confinement to T cells in animals might reflect a greater division of labor in the animal immune system.

Dr. Schulze-Lefert’s information can be found at the website:

http://www.mpiz-koeln.mpg.de/english/research/schulzeLefertGroup/schulzeLefert/index.html