| Autor: |
Medina-Andrés R; Laboratorio de Fisiología y Desarrollo Vegetal, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, México., Solano-Peralta A; Departamento de Química Inorgánica y Nuclear, Facultad de Química, Universidad Nacional Autónoma de México, México D.F., México., Saucedo-Vázquez JP; Departamento de Química Inorgánica y Nuclear, Facultad de Química, Universidad Nacional Autónoma de México, México D.F., México., Napsucialy-Mendivil S; Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México., Pimentel-Cabrera JA; Laboratorio Nacional de Microscopia Avanzada, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México., Sosa-Torres ME; Departamento de Química Inorgánica y Nuclear, Facultad de Química, Universidad Nacional Autónoma de México, México D.F., México., Dubrovsky JG; Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México., Lira-Ruan V; Laboratorio de Fisiología y Desarrollo Vegetal, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, México. |
| Abstrakt: |
During the last 20 years multiple roles of the nitric oxide gas (•NO) have been uncovered in plant growth, development and many physiological processes. In seed plants the enzymatic synthesis of •NO is mediated by a nitric oxide synthase (NOS)-like activity performed by a still unknown enzyme(s) and nitrate reductase (NR). In green algae the •NO production has been linked only to NR activity, although a NOS gene was reported for Ostreococcus tauri and O. lucimarinus, no other Viridiplantae species has such gene. As there is no information about •NO synthesis neither for non-vascular plants nor for non-seed vascular plants, the interesting question regarding the evolution of the enzymatic •NO production systems during land plant natural history remains open. To address this issue the endogenous •NO production by protonema was demonstrated using Electron Paramagnetic Resonance (EPR). The •NO signal was almost eliminated in plants treated with sodium tungstate, which also reduced the NR activity, demonstrating that in P. patens NR activity is the main source for •NO production. The analysis with confocal laser scanning microscopy (CLSM) confirmed endogenous NO production and showed that •NO signal is accumulated in the cytoplasm of protonema cells. The results presented here show for the first time the •NO production in a non-vascular plant and demonstrate that the NR-dependent enzymatic synthesis of •NO is common for embryophytes and green algae. |
