2024-03-29T12:38:17Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1278602022-12-30T09:15:21Zcom_10261_72com_10261_6com_10261_15col_10261_325col_10261_268
urn:hdl:10261/127860
The CBL-interacting protein kinase CIPK23 regulates HAK5-mediated high-affinity K+ uptake in arabidopsis roots
Ragel, Paula
Ródenas, Reyes
García-Martín, Elena
Andrés, Zaida
Villalta, Irene
Nieves-Cordones, Manuel
Rivero, Rosa M.
Martínez, Vicente
Pardo, José M.
Quintero, Francisco J.
Rubio, Francisco
Ministerio de Economía y Competitividad (España)
European Commission
Ministerio de Educación, Cultura y Deporte (España)
11 páginas.-- 7 figuras.-- 66 referencias.-- Supplemental Data The following supplemental materials are available. Supplemental Figure S1. Fresh weight of shoots and roots of the Arabidopsis wild type and mutant lines grown in a range of K+ concentrations. Supplemental Figure S2. K+ concentrations of shoots of Arabidopsis plants grown in a range of K+ concentrations. Supplemental Table S1. Primers used in this work.
Plant growth and development requires efficient acquisition of essential elements. Potassium (K+) is an important macronutrient present in the soil solution at a wide range of concentrations. Regulation of the K+ uptake systems in the roots is essential to secure K+ supply. It has been shown in Arabidopsis (Arabidopsis thaliana) that when the externalK+ concentration is very low (,10 mM), K+ nutrition depends exclusively on the high-affinity K+ transporter5 (HAK5). Low-K+-induced transcriptional activation of the gene encoding HAK5 has been previously reported. Here, we show the posttranscriptional regulation of HAK5 transport activity by phosphorylation. Expression in a heterologous system showed that the Ca2+ sensors calcineurin B-like (CBL1), CBL8, CBL9, and CBL10, together with CBL-interacting protein kinase23 (CIPK23), activated HAK5 in vivo. This activation produced an increase in the affinity and the Vmax of K+ transport. In vitro experiments show that the N terminus of HAK5 is phosphorylated by CIPK23. This supports the idea that phosphorylation of HAK5 induces a conformational change that increases its affinity for K+. Experiments of K+ (Rb+) uptake and growth measurements in low-K+ medium with Arabidopsis single mutants hak5, akt1, and cipk23, double mutants hak5 akt1, hak5 cipk23, and akt1 cipk23, and the triple mutant hak5 akt1 cipk23 confirmed the regulatory role of CIPK23 in planta.
2015-10-16
artículo
Plant Physiology 169(4): 2863-2873 (2015)
0032-0889
http://hdl.handle.net/10261/127860
10.1104/pp.15.01401
1532-2548
http://dx.doi.org/10.13039/501100003329
http://dx.doi.org/10.13039/501100000780
http://dx.doi.org/10.13039/501100003176
26474642
eng
Postprint
http://dx.doi.org/10.1104/pp.15.01401
Sí
openAccess
American Society of Plant Biologists