NITRIC OXIDE: The Versatility of an Extensive Signal Molecule

LORENZO LAMATTINA; CARLOS GARCIA-MATA; MAGDALENA GRAZIANO; GABRIELA PAGNUSSAT

ANNUAL REVIEW OF PLANT BIOLOGY

ANNUAL REVIEWS

Año: 2003 vol. 54 p. 109 - 136

1543-5008

Nitric oxide (NO) is a small highly diffusible gas and a ubiquitousbioactive molecule. Its chemical properties make NO a versatile signal molecule thatfunctions through interactions with cellular targets via either redox or additive chemistry.In plants, NO plays a role in a broad spectrum of pathophysiological and developmentalprocesses. Although nitric oxide synthase (NOS)-dependent NO productionhas been reported in plants, no gene, cDNA, or protein has been isolated to date. Inparallel, precise and regulated NO production can be measured from the activity of theubiquitous enzyme nitrate reductase (NR). In addition to endogenous NO formation,high NO emissions are observed from fertilized soils, but their effects on the physiologyof plants are largely unknown. Many environmental and hormonal stimuli aretransmitted either directly or indirectly by NO signaling cascades. The ability of NO toact simultaneously on several unrelated biochemical nodes and its redox homeostaticproperties suggest that it might be a synchronizing molecule in plants.