The Plant Plasma Membrane pp 457-470
Plasma Membrane and Abiotic Stress
Environmental factors exert influence on nearly every aspect of plant function throughout its life cycle. In response to changing and often unfavorable conditions, stress perception in plants initiates signal transduction events that lead to expression of specific stress-related genes and generation of stress-protecting metabolites. Some of these responses are evidently adaptive and lead to changes that increase the chance of survival under adverse conditions, while others are symptoms of stress injury and are pathological in nature. As stressful abiotic environmental conditions can range from exposure to drought, salinity, cold, freezing, high temperature, anoxia, high light intensity, and nutrient imbalance, a complex and overlapping network of molecular machinery must regulate plant responses to these conditions.
The plasma membrane (PM) of the plant cell acts as an important barrier that separates and shields the cell from its environment. However, the PM is also the site of sensors that interpret environmental conditions and transduce signals to other sites on the membrane, inside the cell, and distal portions of the plant to provide for direct and rapid responses to changing environmental conditions. PM sensors can respond directly to alleviate a stress condition, signal secondary changes at the membrane, or activate signaling cascades that potentiate tertiary changes in stress-regulated gene expression.