Ethylene responses in Arabidopsis seedlings include the reduction of curvature values in the root cap.
Recently, curvature was described as a new trait useful in the analysis of root apex shape. Treating the root profile as a geometric curve revealed that root apex curvature values are lower in ethylene-insensitive mutants (Cervantes E, Tocino A. Geometric analysis of Arabidopsis root apex reveals a new aspect of the ethylene signal transduction pathway in development. J Plant Physiol 2005;162:1038-45). This fact suggests that curvature is regulated by ethylene. In this work, we have determined the curvature values in embryonic roots of wild-type Columbia as well as in ethylene signal-transduction mutants, and found smaller values in embryos of the mutants. We also report on the evolution of root curvature during early development after seed germination. The line Lt16b that expresses GFP in the cell wall has allowed us to investigate the evolution of curvature values in three successive cell layers of seedling roots by confocal microscopy. Treatment of seedlings with norbornadiene resulted in lower curvature values. Our results show details illustrating the effect of ethylene in root curvature.
Noriega
Arturo
A
Departamento de Producción Vegetal, IRNASA-CSIC, Apartado 257, Salamanca, Spain.
Cervantes
Emilio
E
Tocino
Angel
A
D017360:Arabidopsis / Q000187:drug effects* / Q000196:embryology / Q000254:growth & development* / Q000528:radiation effects; D005030:Ethylenes / Q000494:pharmacology*; D005838:Genotype; D008027:Light; D018613:Microscopy, Confocal; D009154:Mutation / Q000235:genetics; D009636:Norbornanes / Q000494:pharmacology; D018518:Plant Root Cap / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development* / Q000528:radiation effects; D036226:Seedlings / Q000187:drug effects* / Q000254:growth & development* / Q000528:radiation effects; D012639:Seeds / Q000187:drug effects / Q000254:growth & development / Q000528:radiation effects; D013997:Time Factors
D005030:Ethylenes; D009636:Norbornanes; C036216:ethylene