Signal transduction and amplification

The classical example is blood clotting, where successive steps involving enzyme-catalyzed proteolysis converts an inactive (or weakly active) proenzyme into its highly active form. Although unknown at the time of Wald s classical report, kinase-type and nucleotidyltransferase-type reactions (See Enzyme Cascade Kinetics) are frequently the source of biological signal transduction and amplification. 

Signal transduction and amplification systems are useful specimens to study when designing molecular devices because they are based on supramolecular interactions between substances. G-proteins play an important role in bio-... 

Preliminary data further suggest the involvement of phosphoinositides in G A3-induced synthesis and secretion of a-amylase in aleurone cells [13]. GA3 activation of protein kinase C-like enzyme has been shown in potato tubers [10]. The in vitro effect of 2,4-D on protein phosphorylation in a membrane fraction isolated from etiolated soybean hypocotyls may also be associated with this system [24]. Further investigation in this field may be valuable in the elucidation of molecular mechanism of phytohormone signal transduction and amplification. 

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