Record ID No. |
6273 |
Author(s) |
Etemadi M.*, Gutjahr C., Couzigou J-M., Zouine M., Lauressergues D., Timmers A., Audran C., Bouzayen M., Bécard G. and Combier J-P. , 2014 |
Affiliation |
*Université Paul Sabatier Toulouse, Unité Mixte de Recherche 5546, Laboratoire de Recherche en Sciences Végétales, F–31326 Castanet-Tolosan cedex, France. |
Title |
Auxin Perception is required for arbuscular development in arbuscular mycorrhizal symbiosis. |
Source. Vol.(no):Page |
Plant Physiology. 166: 281-292. |
Categories |
Arbuscular Mycorrhiza |
Subjects |
Biological Interaction Genetics Physiology |
Sub-subjects |
Hormones |
Host |
Solanum lycopersicum, Medicago truncatula, Oryza sativa |
Organism |
Rhizophagus irregularis |
Country |
France |
Abstracts |
Most land plant species live in symbiosis with arbuscular mycorrhizal fungi. These fungi differentiate essential functional
structures called arbuscules in root cortical cells from which mineral nutrients are released to the plant. We investigated the role of microRNA393 (miR393), an miRNA that targets several auxin receptors, in arbuscular mycorrhizal root colonization. Expression of the
precursors of the miR393 was down-regulated during mycorrhization in three different plant species: Solanum lycopersicum, Medicago truncatula, and Oryza sativa. Treatment of S. lycopersicum, M. truncatula, and O. sativa roots with concentrations of synthetic auxin analogs that did not affect root development stimulated mycorrhization, particularly arbuscule formation. DR5-GUS, a reporter for auxin response, was preferentially expressed in root cells containing arbuscules. Finally, overexpression of miR393 in root tissues
resulted in down-regulation of auxin receptor genes (transport inhibitor response1 and auxin-related F box) and underdeveloped arbuscules in all three plant species. These results support the conclusion that miR393 is a negative regulator of arbuscule formation by
hampering auxin perception in arbuscule-containing cells. |