title: Nitric oxide: a multitasked signaling gas in plants.
abstract: Nitric oxide (NO) is a gaseous reactive oxygen species (ROS) that has evolved as a signaling hormone in many physiological processes in animals. In plants it has been demonstrated to be a crucial regulator of development, acting as a signaling molecule present at each step of the plant life cycle. NO has also been implicated as a signal in biotic and abiotic responses of plants to the environment. Remarkably, despite this plethora of effects and functional relationships, the fundamental knowledge of NO production, sensing, and transduction in plants remains largely unknown or inadequately characterized. In this review we cover the current understanding of NO production, perception, and action in different physiological scenarios. We especially address the issues of enzymatic and chemical generation of NO in plants, NO sensing and downstream signaling, namely the putative cGMP and Ca(2+) pathways, ion-channel activity modulation, gene expression regulation, and the interface with other ROS, which can have a profound effect on both NO accumulation and function. We also focus on the importance of NO in cell-cell communication during developmental processes and sexual reproduction, namely in pollen tube guidance and embryo sac fertilization, pathogen defense, and responses to abiotic stress.
authors: Instituto Gulbenkian de Ciência, P-2780-156 Oeiras, Portugal.
authors: Patricia
authors: P
authors: Domingos
authors: Instituto Gulbenkian de Ciência, P-2780-156 Oeiras, Portugal.
authors: Ana Margarida
authors: AM
authors: Prado
authors: Division of Biological and Environmental Sciences and Engineering, 4700 King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia.
authors: Aloysius
authors: A
authors: Wong
authors: Division of Biological and Environmental Sciences and Engineering, 4700 King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia.
authors: Christoph
authors: C
authors: Gehring
authors: Instituto Gulbenkian de Ciência, P-2780-156 Oeiras, Portugal; Department of Cell Biology and Molecular Genetics, University of Maryland, 0118 BioScience Research Building, College Park, MD 20742-5815, USA. Electronic address: jfeijo@umd.edu.
authors: Jose A
authors: JA
authors: Feijo
mesh_terms: D002450:Cell Communication / Q000502:physiology; D009569:Nitric Oxide / Q000378:metabolism*; D010944:Plants / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology
chemical_list: D017382:Reactive Oxygen Species; D009569:Nitric Oxide
keywords: cell communication; nitric oxide (NO); plant sexual reproduction; pollen; reactive oxygen species (ROS)