IAOx induces the SUR phenotype and differential signalling from IAA under different types of nitrogen nutrition in Medicago truncatula roots

Indole-3-acetaldoxime (IAOx) is a particularly relevant molecule as an intermediate in the pathway for tryptophan-dependent auxin biosynthesis. The role of IAOx in growth-signalling and root phenotype is poorly studied in cruciferous plants and mostly unknown in non-cruciferous plants. We synthesize...

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Detalles Bibliográficos
Autores: Buezo Bravo, Javier, Esteban Terradillos, Raquel, Cornejo Ibergallartu, Alfonso, López Gómez, Pedro, Marino Bilbao, Daniel, Chamizo Ampudia, Alejandro, Gil Idoate, María José, Martínez Merino, Víctor, Morán Juez, José Fernando
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2019
País:España
Institución:Universidad Pública de Navarra
Repositorio:Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
OAI Identifier:oai:academica-e.unavarra.es:2454/34425
Acceso en línea:https://hdl.handle.net/2454/34425
Access Level:acceso abierto
Palabra clave:Ammonium
Auxin
Indole-3-acetaldoxime
Nitrate
Oximes
Phenotype
Superroot
Root
Urea
CYP71A
Descripción
Sumario:Indole-3-acetaldoxime (IAOx) is a particularly relevant molecule as an intermediate in the pathway for tryptophan-dependent auxin biosynthesis. The role of IAOx in growth-signalling and root phenotype is poorly studied in cruciferous plants and mostly unknown in non-cruciferous plants. We synthesized IAOx and applied it to M. truncatula plants grown axenically with NO3-, NH4+ or urea as the sole nitrogen source. During 14 days of growth, we demonstrated that IAOx induced an increase in the number of lateral roots, especially under NH4+ nutrition, while elongation of the main root was inhibited. This phenotype is similar to the phenotype known as “superroot” previously described in SUR1- and SUR2-defective Arabidopsis mutants. The effect of IAOx, IAA or the combination of both on the root phenotype was different and dependent on the type of N-nutrition. Our results also showed the endogenous importance of IAOx in a legume plant in relation to IAA metabolism, and suggested IAOx long-distance transport depending on the nitrogen source provided. Finally, our results point out to CYP71A as the major responsible enzymes for IAA synthesis from IAOx.