ABSTRACT
Polyamines are low molecular weight polycations that are found in all organisms. In plants, they have been implicated in a wide range of biological processes, including growth, development and stress responses. Recently, several key genes of the polyamine biosyn-thetic pathways have been cloned and shown to be developmentally regulated. The availability of these genes has allowed the use of antisense and sense transgenic approaches to specifically modulate the levels of polyamines in plants. These experiments have clearly demonstrated that polyamines are essential for normal growth and development and that it may be possible to exploit transgenic approaches to specifically manipulate some biological processes for biotechnological purposes.
