RT Journal Article
T1 Arabidopsis lines with modified ascorbate concentrations reveal a link between ascorbate and auxin biosynthesis.
A1 Fenech, Mario
A1 Zulian, Viviane
A1 Moya-Cuevas, José
A1 Arnaud, Dominique
A1 Morilla, Ian
A1 Smirnoff, Nicholas
A1 Botella-Mesa, Miguel Ángel
A1 Stepanova, Anna
A1 Alonso, José M.
A1 Martín-Pizarro, Carmen
A1 Amorim-Silva, Vitor
K1 Plantas - Crecimiento
K1 Fisiología vegetal
K1 Auxina
K1 Hormonas vegetales
AB Ascorbate is the most abundant water-soluble antioxidant in plants and an essential molecule for normal plant development. Although present in all green plants, ascorbate concentrations vary among plant species and tissues. While ascorbate accumulation is a trait of nutritional, and therefore, agronomical interest, the impact of different concentrations on cellular homeostasis remains elusive. To shed light on this question, we compared Arabidopsis (Arabidopsis thaliana) lines with very low (vtc2 mutant, 20% of wild-type (WT) levels), low (vtc4 mutant, 65% of WT levels), and high (vtc2/OE-VTC2, 165% of WT levels) ascorbate concentration in four-week-old rosette leaves. An 80% reduction of ascorbate increased the expression of genes implicated in defense against pathogens but repressed genes associated with abiotic stress responses. Unexpectedly, lines with increased (165% of WT) and decreased (65% of WT) ascorbate levels shared 85% of induced transcription factors and the gene ontology terms associated with their transcriptional programs. We identified TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS 1 (TAA1), a gene encoding the enzyme that catalyzes the first step of auxin biosynthesis, among the group of genes whose expression was positively correlated with ascorbate content. Using a combination of genetic and pharmacological approaches in fluorescent and histochemical reporter lines for auxin biosynthesis and signaling activity, we revealed that TAA1- and TAA1 RELATED 2 (TAR2)-mediated auxin biosynthesis is necessary for plants to cope with increased ascorbate concentration in a light-dependent manner, revealing a layer of complexity in the regulatory landscape of redox homeostasis.
PB Oxford University Press
YR 2025
FD 2025-12-23
LK https://hdl.handle.net/10630/41420
UL https://hdl.handle.net/10630/41420
LA eng
NO M Fenech, V Zulian, J Moya-Cuevas, D Arnaud, I Morilla, N Smirnoff, M A Botella, A N Stepanova, J M Alonso, C Martin-Pizarro, V Amorim-Silva, Arabidopsis lines with modified ascorbate concentrations reveal a link between ascorbate and auxin biosynthesis, Plant Physiology, 2025, kiaf667, https://doi.org/10.1093/plphys/kiaf667
NO Ministerio Español de Educación, Cultura y Deporte para la Formación del Profesorado Universitario
NO U.S.A. National Science Foundation
NO Consejería de Universidad, Investigación e Innovación de la Junta de Andalucía
NO Biotechnology and Biological Sciences Research Council
NO U.S. Department of Agriculture’s National Institute of Food and Agriculture
NO Universidad de Málaga/CBUA
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 20 ene 2026