Chapter 4 – Resistance of Plants to Cu Stress: Transgenesis

Copper (Cu) is reported to play a dual role in plants. At low concentrations, it functions as a necessary element participating in carbon assimilation, transport of organic substances, growth, and metabolism of cell walls. Cu needs to sustain the plant based on its role in enzymatic catalysis, in redox reactions, and in the electron transport in the respiratory and photosynthetic chains. In high concentrations, it has a toxic effect. This is discussed, as are mechanisms of maintenance of intracellular Cu-homeostasis, including regulation of Cu translocation, its complexation with organic substances in plant and in soil, and its sequestration in cell organelles (vacuole) and organs (roots). A necessity to study transport processes (translocation of Cu and other ions essential for plants as well as assimilates) is discussed. Cu complexation process with natural and artificially synthesized chelators, the interaction of plants with microorganisms must be applied in the development of practical methods for phytoremediation. Because multifactorial defense reactions of plants in stress conditions and necessity of integrated regulation of protection against various stresses, it seems preferable to create transgenic plants expressing transcription factors regulating expression of several groups of genes. This chapter describes transgenic plants expressing Osmyb-gene which have increased resistance to such diverse factors as cold, drought, and Cu.