ABSTRACT
Reactive oxygen species (ROS) are ions or small molecules consisting of oxygen ions and free radicals of inorganic and organic forms. ROS are typically formed during cellular metabolic reactions involving oxygen. They are often referred to as byproducts of redox reactions, although they play important roles in the plant cell. These roles include but are not limited to cell signaling, innate immunity, and apoptosis. The level of radicals produced is highly regulated in the cell but can be easily infl uenced by the external environment. Exposure to stressors such as temperature,
Department of Biological Sciences, University of Lethbridge, Lethbridge, AB. T1K 3M4, Canada, Fax: 403 329 2242, E-mail: igor.kovalchuk@uleth.ca
water availability, UVC, ionizing radiation and many others generates a substantial amount of free radicals that cells have to deal with. An increase in the level of radicals creates two major problems: it can physically damage a variety of molecules such as proteins, lipids, and DNA; it can disbalance signaling mechanisms or interfere with innate immunity.
