Interaction Between ABA Signaling and Copper Homeostasis in Arabidopsis thaliana.
ABA is involved in plant responses to non-optimal environmental conditions, including nutrient availability. Since copper (Cu) is a very important micronutrient, unraveling how ABA affects Cu uptake and distribution is relevant to ensure adequate Cu nutrition in plants subjected to stress conditions. Inversely, knowledge about how the plant nutritional status can interfere with ABA biosynthesis and signaling mechanisms is necessary to optimize stress tolerance in horticultural crops. Here the reciprocal influence between ABA and Cu content was addressed by using knockout mutants and overexpressing transgenic plants of high affinity plasma membrane Cu transporters (pmCOPT) with altered Cu uptake. Exogenous ABA inhibited pmCOPT expression and drastically modified COPT2-driven localization in roots. ABA regulated SPL7, the main transcription factor responsive for Cu deficiency responses, and subsequently affected expression of its targets. ABA biosynthesis (aba2) and signaling (hab1-1 abi1-2) mutants differentially responded to ABA according to Cu levels. Alteration of Cu homeostasis in the pmCOPT mutants affected ABA biosynthesis, transport and signaling as genes such as NCED3, WRKY40, HY5 and ABI5 were differentially modulated by Cu status, and also in the pmCOPT and ABA mutants. Altered Cu uptake resulted in modified plant sensitivity to salt-mediated increases in endogenous ABA. The overall results provide evidence for reciprocal cross-talk between Cu status and ABA metabolism and signaling.
Departamento de Bioquímica y Biología Molecular, Universitat de València, 46100-Burjassot, Spain.|These authors contributed equally to this work.
Àngela
À
Carrió-Seguí
Departamento de Bioquímica y Biología Molecular, Universitat de València, 46100-Burjassot, Spain.|These authors contributed equally to this work.|Present address: Section of Plant Biology, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA.
Paco
P
Romero
Departamento de Biología Vegetal, Universitat de València, 46100-Burjassot, Spain.
Amparo
A
Sanz
Departamento de Bioquímica y Biología Molecular, Universitat de València, 46100-Burjassot, Spain lola.penarrubia@uv.es.
Lola
L
Peñarrubia
D000040:Abscisic Acid / Q000096:biosynthesis / Q000378:metabolism* / Q000494:pharmacology; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D003300:Copper / Q000378:metabolism* / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D055786:Gene Knockout Techniques; D017343:Genes, Plant; D006706:Homeostasis / Q000187:drug effects; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D018384:Oxidative Stress / Q000187:drug effects; D010641:Phenotype; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D015398:Signal Transduction / Q000187:drug effects; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D014158:Transcription, Genetic / Q000187:drug effects
D029681:Arabidopsis Proteins; D026901:Membrane Transport Proteins; D012965:Sodium Chloride; D000040:Abscisic Acid; D003300:Copper
Abscisic acid; Arabidopsis thaliana; COPT; Copper deficiency; Hormonal signaling; Nutrient homeostasis