Front-runners in plant–microbe interactions

Abstract

Available online at www.sciencedirect.com Front-runners in plant–microbe interactions Editorial overview Pamela C Ronald and Ken Shirasu Current Opinion in Plant Biology 2012, 15:345–348 For a complete overview see the Issue Available online 12th July 2012 1369-5266/$ – see front matter, # 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.pbi.2012.06.001 Pamela C Ronald 1,2 Plant Pathology Faculty, The Genome Center, University of California, Davis, CA 95616, USA Joint Bioenergy Institute, Emeryville, CA 94608, USA e-mail: pcronald@ucdavis.edu Pamela Ronald is professor, Department of Plant Pathology and the Genome Center at the University of California, Davis. She also serves as Director of Grass Genetics at the Joint Bioenergy Institute. Ronald’s laboratory has engineered rice for resistance to disease and tolerance to flooding, which seriously threaten rice crops in Asia and Africa. Ronald led the isolation of the rice XA21 immune receptor, the bacterial Ax21 quorum sensing factor and the rice Sub1A submergence tolerance transcription factor. In 1996, she established the Genetic Resources Recognition fund, a mechanism to recognize intellectual property contributions from less developed countries. She and her colleagues were recipients of the USDA 2008 National Research Initiative Discovery Award for their work on rice submergence tolerance. Ronald was awarded a Guggenheim Fellowship, the Fulbright–Tocqueville Distinguished Chair and the National Association of Science Writers Science in Society Journalism Award. She is an elected fellow of the American Association for the Advancement of Science. Ronald has written opinion pieces for the Boston Globe, The Economist, and the New York Times and is a blogger for National Geographic’s ScienceBlogs. She is coauthor with her husband, Raoul Adamchak, an organic farmer, of ‘Tomorrow’s Table: Organic Farming, Genetic, and the Future of Food’. Bill Gates calls the book ‘a fantastic piece of work’. In 2011, Ronald was selected as one of the 100 most creative people in business by Fast Company Magazine. Ken Shirasu Plant Immunity Research Group, RIKEN Plant Science Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan The Ken Shirasu laboratory investigates the molecular mechanisms underlying plant immunity, with a focus on signaling proteins that are modified upon infection. The Shirasu lab also studies Striga spp., parasitic plants that cause devastating agricultural damages especially in Africa, using genomic tools to understand how plants infect other plants. www.sciencedirect.com Plants and microbes, abundant in the environment, can peacefully coexist or battle for survival. Plants must determine if the associated microbes are friends or foes, while microbes attempt to manipulate the plant host to access nutrients and/or create shelter. In this volume of Current Opinions in Plant Biology, we highlight multiple topics in the field, including immune receptor biology, metabolomics, signal transduction, symbiosis biology, and microbial genomics. Receptors mediating immunity For over 100 years, genes for resistance have been used in breeding. However, until recently the molecular basis of this immunity was unknown. Advances in the last 15 years has revealed that plant and animal innate immune systems depend on a diverse assortment of cell surface and cytoplasmic receptors that detect and respond to invading pathogens. In plants, these receptors are commonly classified into a group that recog- nizes conserved microbial signatures (called pattern recognition receptors, PRRs) and a group that recognizes highly variable effectors (nucleotide binding-leucine rich repeat receptors, NB-LRRs). The first group contains both extracellular membrane bound receptors and intracellular receptors that frequently contain (or associate with) non-arginine–aspartate (non-RD) kinases. The second group includes intracellular NB-LRRs, which are often fused to additional domains but typically lack kinase domains. These two systems of microbial perception in plants are commonly referred to as Pathogen Associated Molecular Pattern [PAMP] Triggered Immunity (PTI) and Effector Triggered Immunity (ETI), respectively. Understand- ing how microbial signals are converted into PTI or ETI remains a funda- mentally important issue. Four reviews in this volume address these issues. First the mechanism of action of three well-characterized PRRs, rice Xa21 and Arabidopsis FLS2 and EFR, are addressed. Monaghan et al. discuss the important role of multiprotein complexes at the plasma membrane that interact with PRRs. The authors describe the molecular interactions and protein modifications that have been uncovered and shown to occur between PRRs and their regulatory proteins. These studies have provided import- ant mechanistic insight into how plants avoid infection and achieve immunity. Dardick et al. note that the non-RD subclass of kinases is associated with PRR-mediated immunity. For example, of the approximately 75 plant receptor-like kinases (RLKs) that have been functionally characterized, nearly one dozen of these are non-RD kinases, all of which have known or Current Opinion in Plant Biology 2012, 15:345–348