Recent advances and emerging trends in plant hormone signalling
Aaron Santner ‘ & Mark Estelle have reviewed plant homones in Nature 25th June 2009
In eating frit and vegetables there are many different molecules whose function when eaten by man is unknown included in these are plant hormones.
Plant growth and development is regulated by plant hormones. During the last 15 years the number of known plant hormones has grown from five to at least ten. Furthermore, many of the proteins involved in plant hormone signalling pathways have been identified, including receptors for many of the major hormones. Strikingly, the ubiquitin-proteasome pathway plays a central part in most hormone-signalling pathways. In addition, recent studies confirm that hormone signalling is integrated at several levels during plant growth and development.
Because plants have a sessile lifestyle, they must adjust to numerous external stimuli and coordinate their growth and development accordingly. The plant hormones, a group of structurally unrelated small molecules, are central to the ntegration of diverse environmental cues with a plant’s genetic program. The ‘classical’ phytohormones, identified during the first half of the twentieth century, are auxin, abscisic acid, cytokinin, gibberellin and ethylene.
More recently, several additional compounds have been recognized as hormones, including brassinosteroids, jasrnonate, salicylic acid, nitric oxide and strigolactcnes
Plants also use several peptide hormones to regulate various growth responses, Most hormones are involved in many different processes ( hormone synthesis, transport and signalling pathways, as well as by the diversity of interactions among hormones) to control growth responses. throughout plant growth and development. Genetic screens have identified many of the proteins involved in hormone signalling
Receptors for auxin, gibberellin , jasmonate and abscisic acid have now been identified. . Some hormones (cytokinins, ethylene and the brassinosteroids) use well-characterized signalling mechanisms.
The auxin and jasmonate receptors, as well as proteins in gibberellin signalling, have highlighted a novel mechanism for hormone perception in which the ubiquitin–proteasome pathway.
Has this any relevance to human nutrition? Who knows , but we do know that eating fruit and vegetables is good for health, and these plant hormones may be of biological value.
Santner and Estelle 2009 Recent advances and emerging trends in plant hormone signalling. Nature vol 459 pp 1071-78
- Martin Eastwood