Conserved transport mechanisms but distinct auxin responses govern shoot patterning in Selaginella kraussiana.
New Phytol
; 198(2): 419-428, 2013 Apr.
Article
in En
| MEDLINE
| ID: mdl-23421619
ABSTRACT
To provide a comparative framework to understand the evolution of auxin regulation in vascular plants, the effect of perturbed auxin homeostasis was examined in the lycophyte Selaginella kraussiana. Polar auxin transport was measured by tracing tritiated IAA in excised shoots. Shoots were cultured in the presence of auxin efflux inhibitors and exogenous auxin, and developmental abnormalities were documented. Auxin transport in Selaginella shoots is exclusively basipetal, as in angiosperms. Perturbed auxin transport results in the loss of meristem maintenance and abnormal shoot architecture. Dichotomous root branching in Selaginella appears to be regulated by an antagonistic relationship between auxin and cytokinin. The results suggest that basipetal polar auxin transport occurred in the common ancestor of lycophytes and euphyllophytes. Although the mechanisms of auxin transport appear to be conserved across all vascular plants, distinct auxin responses govern shoot growth and development in lycophytes and euphyllophytes.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Plant Shoots
/
Body Patterning
/
Selaginellaceae
/
Indoleacetic Acids
Language:
En
Journal:
New Phytol
Journal subject:
BOTANICA
Year:
2013
Document type:
Article
Affiliation country: