caa a22 4500 477100023 CHVBK 20180405111538.0 cr unu---uuuuu 170330e19960901xx s 000 0 eng 10.1007/BF00196658 doi (NATIONALLICENCE)springer-10.1007/BF00196658 The response to auxin of rapeseed ( Brassica napus L.) roots displaying reduced gravitropism due to transformation by Agrobacterium rhizogenes [Elektronische Daten] [Valérie Legué, Dominique Driss-Ecole, Régis Maldiney, Mark Tepfer, Gérald Perbal] It has recently been documented that, compared to untransformed controls, the roots of oilseed rape (Brassica napus L. CV CrGC5) seedlings transformed by Agrobacterium rhizogenes A4 show a reduced gravitropic reaction (Legué et al. 1994, Physiol Plant 91: 559-566). After stimulation at 90°C or 135°, the transformed root tips curve, but never reach a vertical orientation. In the present study, we investigated the causes of reduced gravitropic bending observed in stimulated transformed root tips. First, we localized the gravitropic curvature in normal and in transformed roots after 1.5 h of stimulation. The cells involved in root curvature (target cells) corresponded at the cellular level to the apical part of the zone of increasing cell length. In transformed roots grown in the vertical position, these cells showed a reduction in cell length compared to controls. Because auxin is considered to be the gravitropic mediator, the response of normal and transformed roots to exogenous auxin was studied. Indole-3-acetic acid (IAA) was applied along the first 3 mm using resin beads loaded with the hormone. In comparison to normal roots, transformed roots showed reduced bending toward the bead at all points of bead application. Moreover, the cells which responded to IAA corresponded to the target cells involved in the gravitropic reaction. The level of endogenous IAA was lower in transformed roots. Thus, it was concluded that the modified behavior of transformed roots during gravitropic stimulation could be due to differences either in IAA levels or in reactivity of the target cells to the message from the cap. Springer-Verlag, 1996 Auxin nationallicence Brassica nationallicence Graviresponse nationallicence pRi T-DNA nationallicence Target cells nationallicence Transformed roots nationallicence DEZ : distal elongation zone nationallicence ELISA : enzymelinked immunosorbent assay nationallicence T-DNA : DNA transferred from Agrobacterium rhizogenes to the plant genome nationallicence Legué Valérie Laboratoire de Cytologie Expérimentale et Morphogenèse Végétale, Université Pierre et Marie Curie, 4 Place Jussieu Bâtiment N2, 05, Paris Cedex, France aut Driss-Ecole Dominique Laboratoire de Cytologie Expérimentale et Morphogenèse Végétale, Université Pierre et Marie Curie, 4 Place Jussieu Bâtiment N2, 05, Paris Cedex, France aut Maldiney Régis Laboratoire de Physiologie du Développement des Plantes, CNRS URA 2135, Université Pierre et Marie Curie, 4 Place Jussieu Tour 53, 05, Paris Cedex, France aut Tepfer Mark Laboratoire de Biologie Cellulaire, INRA-Centre de Versailles, F-78026, Versailles Cedex, France aut Perbal Gérald Laboratoire de Cytologie Expérimentale et Morphogenèse Végétale, Université Pierre et Marie Curie, 4 Place Jussieu Bâtiment N2, 05, Paris Cedex, France aut Planta Springer-Verlag 200/1(1996-09-01), 119-124 0032-0935 200:1<119 1996 200 425 https://doi.org/10.1007/BF00196658 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00196658 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Legué Valérie Laboratoire de Cytologie Expérimentale et Morphogenèse Végétale, Université Pierre et Marie Curie, 4 Place Jussieu Bâtiment N2, 05, Paris Cedex, France aut NATIONALLICENCE 700 1- Driss-Ecole Dominique Laboratoire de Cytologie Expérimentale et Morphogenèse Végétale, Université Pierre et Marie Curie, 4 Place Jussieu Bâtiment N2, 05, Paris Cedex, France aut NATIONALLICENCE 700 1- Maldiney Régis Laboratoire de Physiologie du Développement des Plantes, CNRS URA 2135, Université Pierre et Marie Curie, 4 Place Jussieu Tour 53, 05, Paris Cedex, France aut NATIONALLICENCE 700 1- Tepfer Mark Laboratoire de Biologie Cellulaire, INRA-Centre de Versailles, F-78026, Versailles Cedex, France aut NATIONALLICENCE 700 1- Perbal Gérald Laboratoire de Cytologie Expérimentale et Morphogenèse Végétale, Université Pierre et Marie Curie, 4 Place Jussieu Bâtiment N2, 05, Paris Cedex, France aut NATIONALLICENCE 773 0- Planta Springer-Verlag 200/1(1996-09-01), 119-124 0032-0935 200:1<119 1996 200 425 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer