Nitric oxide: an active nitrogen molecule that modulates cellulose synthesis in tomato roots.
Nitric oxide (NO) is a bioactive molecule involved in several growth and developmental processes in plants. These processes are mostly characterized by changes in primary and secondary metabolism. Here, the effect of NO on cellulose synthesis in tomato (Solanum lycopersicum) roots was studied. The phenotype of roots, cellulose content, the incorporation of 14C-glucose into cellulosic fraction and the expression of tomato cellulose synthase (CESA) transcripts in roots treated with the NO donor sodium nitroprusside (SNP) were analysed. Nitric oxide affected cellulose content in roots in a dose dependent manner. Low concentrations of SNP (pmoles of NO) increased cellulose content in roots while higher concentrations of SNP (nmoles of NO) had the opposite effect. This result correlated with assays of 14C-glucose incorporation into cellulose in roots. The effect of NO on 14C-glucose incorporation into cellulose was transient and reversible. Microscopic analysis of roots suggested that NO affected primary cell wall cellulose synthesis. Three tomato cellulose synthase (SICESA) transcripts were identified. Reverse transcriptase polymerase chain reaction experiments were carried out and indicated that SICESA1 and SICESA3 levels were affected by high NO concentrations. Together, these results support the hypothesis that variations in NO levels influence cellulose synthesis and content in roots.
Correa-Aragunde
Natalia
N
Instituto de Investigaciones Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata. CC 1245, 7600 Mar del Plata, Argentina.
Lombardo
Cristina
C
Instituto de Investigaciones Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata. CC 1245, 7600 Mar del Plata, Argentina.|Departamento de Biología, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata. CC 1245, 7600 Mar del Plata, Argentina.
Lamattina
Lorenzo
L
Instituto de Investigaciones Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata. CC 1245, 7600 Mar del Plata, Argentina.
D000595:Amino Acid Sequence; D002482:Cellulose / Q000096:biosynthesis*; D004305:Dose-Response Relationship, Drug; D018506:Gene Expression Regulation, Plant / Q000502:physiology; D018551:Solanum lycopersicum / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008969:Molecular Sequence Data; D009569:Nitric Oxide / Q000378:metabolism*; D009599:Nitroprusside / Q000494:pharmacology; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism; D018517:Plant Roots / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D013997:Time Factors
D010940:Plant Proteins; D009599:Nitroprusside; D009569:Nitric Oxide; D002482:Cellulose