Back to Search
Start Over
Effects of conditional IPT-dependent cytokinin overproduction on root architecture of Arabidopsis seedlings.
- Source :
-
Plant & cell physiology [Plant Cell Physiol] 2008 Apr; Vol. 49 (4), pp. 570-82. Date of Electronic Publication: 2008 Feb 21. - Publication Year :
- 2008
-
Abstract
- Cytokinin (CK) has been known to inhibit primary root elongation and suggested to act as an auxin antagonist in the regulation of lateral root (LR) formation. While the role of auxin in root development has been thoroughly studied, the detailed and overall description of CK effects on root system morphology, particularly that of developing lateral root primordia (LRPs), and hence its role in organogenesis is still in progress. Here we examine the effects of conditional endogenous CK overproduction on root architecture and consider its temporal aspect during the early development of Arabidopsis thaliana. We employed the pOp/LhGR system to induce ectopic ipt overexpression with a glucocorticoid dexamethasone at designated developmental points. The transient CaMV 35S>GR>ipt transactivation greatly enhanced levels of biologically active CKs of zeatin (Z)-type and identified a distinct developmental interval during which primary root elongation is susceptible to increases in endogenous CK production. Long-term CK overproduction inhibited primary root elongation by reducing quantitative parameters of primary root meristem, disturbed a characteristic graded distribution pattern of auxin response in LRPs and impaired their development. Our findings indicate the impact of perturbed endogenous CK on the regulation of asymmetric auxin distribution during LRP development and imply that there is cross-talk between auxin and CK during organogenesis in A. thaliana.
- Subjects :
- Alkyl and Aryl Transferases genetics
Arabidopsis cytology
Arabidopsis genetics
Dexamethasone pharmacology
Gene Expression Regulation, Plant drug effects
Indoleacetic Acids metabolism
Meristem cytology
Meristem drug effects
Plant Roots cytology
Plant Roots drug effects
Plant Roots growth & development
Plant Stems cytology
Plant Stems drug effects
Seedlings drug effects
Zeatin metabolism
Alkyl and Aryl Transferases metabolism
Arabidopsis anatomy & histology
Arabidopsis enzymology
Cytokinins biosynthesis
Plant Roots anatomy & histology
Seedlings anatomy & histology
Subjects
Details
- Language :
- English
- ISSN :
- 1471-9053
- Volume :
- 49
- Issue :
- 4
- Database :
- MEDLINE
- Journal :
- Plant & cell physiology
- Publication Type :
- Academic Journal
- Accession number :
- 18296451
- Full Text :
- https://doi.org/10.1093/pcp/pcn029