Formation and possible roles of nitric oxide in plant roots.
Nitric oxide has been reported to act as a signalling molecule in different plant tissues and to participate in a variety of physiological processes. It is produced by different enzymes and sources. The root-specific plasma membrane-bound enzymes forming NO from the substrates nitrate and nitrite are of particular interest because roots serve as interfaces between plants and the soil. The co-ordinated activity of the root-specific plasma membrane-bound nitrate reductase (PM-NR) and nitrite:NO reductase (NI-NOR) suggests that NO might also be involved in root signalling and development. The rate of enzymatic production of this NO depends largely on the environmental conditions, mainly the availability of nitrate and oxygen and it is proposed that this NO plays a role during anoxia as an indicator of the external nitrate availability and in regulating symbiotic interactions at the root surface.
Stöhr
Christine
C
Institut für Botanik, Ernst-Moritz-Arndt-Universität, Grimmer Strasse 88, D-17487 Greifswald, Germany. stoehr@uni-greifswald.de
Stremlau
Stefanie
S
D002462:Cell Membrane / Q000378:metabolism; D009565:Nitrate Reductases / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism / Q000502:physiology*; D009572:Nitrite Reductases / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D018517:Plant Roots / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D015398:Signal Transduction; D014026:Nicotiana / Q000033:anatomy & histology / Q000378:metabolism
D009569:Nitric Oxide; D009565:Nitrate Reductases; D009572:Nitrite Reductases; D010100:Oxygen