Signal Perception and Transduction in Plants
Plants are sessile organisms and are not able to move away from adverse environmental conditions and must response to an array of environmental and developmental cues. They heavily rely on high sensitivity detection and adaptation mechanisms to environmental perturbations. Signal transduction, the means whereby cells construct response to a signal, is a recently defined focus of research in plant biology. Over the past decade our understanding of plant signaling pathways has increased greatly, in part due to the use of molecular genetics and biochemical tools in model plants for example Arabidopsis thaliana and Medicago truncatula. This has assisted us in the identification of components of many signal transduction pathways in diverse physiological systems for example hormonal, developmental and environmental signal transduction pathways and cross-talk between them. During the last 15 years the number of known plant hormones has grown from five to at least ten. Furthermore, many of the proteins involved in plant hormone signaling pathways have been identified, including receptors for many of the major hormones. In addition, recent studies confirm that hormone signaling is integrated at several levels during plant growth and development. In this review paper we have covered recent work in signaling pathway in plants especially how plants sense biotic and abiotic stresses and the potential mechanisms by which different chemical molecules and their downstream signaling components modulates stress tolerance.