Plant, Cellular and Molecular Biology

Plant Hormones and Metabolic engineering

Plant Hormones are also termed as Phytohormones are signal molecules that regulate Plant processes produced within the plants that occur in extremely low concentration. It controls all aspects of growth and development from the embryogenesis. The regulations of organ size, pathogen defence, stress tolerance through to reproductive development. Each plant hormone is capable of producing the hormone. Plant hormones are also used in human use and salicylic acid and Jasmonic acid has been widely used in Pharmaceuticals Company.

Metabolic engineering defined as ‘‘the improvement of cellular activities by manipulation of enzymatic, transport, and regulatory functions of the cell with the use of recombinant DNA technologies.’’ Today, the availability of the complete genome sequence for several plants, together with the development of powerful techniques for the transformation and stable or transient expression of genes in plants brings plant metabolic engineering as a strong alternative to classical chemical synthesis for the production of pharmaceuticals and other important industrial compounds. Plant metabolic engineering involves the manipulation of existing metabolic pathways by either increasing or diverting flux to desire or from undesired products, respectively, or the generation of chemical entities not normally found in the plant production system through the introduction of genes from other organisms. Essential elements in the toolbox of the metabolic engineer are mechanisms to eliminate or overexpress gene activity.

There are so many plant hormones but the major plant hormones are five Hormones which includes Auxin, Cytokinin, Ethylene, Abscisic and Gibberellin. These hormones have different functions. Auxin promotes cell elongation; Cytokinin stimulates bud elongation in tissue culture; Ethylene leads to release in dormancy state and stimulates shoot and root growth along with differentiation; Abscisic acid stimulates closing of stomata and inhibit shoot growth and; Gibberellin present in meristems of apical buds and roots and embryo stimulates stem elongation and leads to the development of seedless fruit and delays senescence in leaves and citrus fruits