Insights into the mechanisms of transport and regulation of the arabidopsis high-affinity K+ transporter HAK51
| Autor: | Francisco Rubio, Alberto Lara, José M. Pardo, Almudena Martínez-Martínez, Jesús Amo, Vicente Martínez, Francisco J. Quintero, Paula Ragel, Manuel Nieves-Cordones, Reyes Ródenas |
|---|---|
| Přispěvatelé: | Centro de Edafologia y Biologia aplicada del Segura (CEBAS - CSIC), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Laboratoire de Recherche en Sciences Végétales (LRSV), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Instituto de Bioquimica Vegetal y Fotosintesis (IBVF) |
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
0106 biological sciences
Regular Issue Molecular model Physiology Arabidopsis Transport Plant Science Bacillus subtilis Bioenergetics Genes Plant 01 natural sciences 03 medical and health sciences Residue (chemistry) Potassium-Hydrogen Antiporters Gene Expression Regulation Plant Genetics Arabidopsis thaliana [SDV.BV]Life Sciences [q-bio]/Vegetal Biology Cation Transport Proteins 030304 developmental biology 0303 health sciences Membranes biology Chemistry Arabidopsis Proteins Genetic Variation Transporter Biological Transport biology.organism_classification Mutation Biophysics Phosphorylation Function (biology) 010606 plant biology & botany |
| Zdroj: | Plant Physiology Plant Physiology, American Society of Plant Biologists, 2021, 185 (4), pp.1860-1874. ⟨10.1093/plphys/kiab028⟩ Plant Physiol |
| ISSN: | 0032-0889 1532-2548 |
| DOI: | 10.1093/plphys/kiab028⟩ |
| Popis: | The high-affinity K+ transporter HAK5 from Arabidopsis (Arabidopsis thaliana) is essential for K+ acquisition and plant growth at low micromolar K+ concentrations. Despite its functional relevance in plant nutrition, information about functional domains of HAK5 is scarce. Its activity is enhanced by phosphorylation via the AtCIPK23/AtCBL1-9 complex. Based on the recently published three-dimensionalstructure of the bacterial ortholog KimA from Bacillus subtilis, we have modeled AtHAK5 and, by a mutational approach, identified residues G67, Y70, G71, D72, D201, and E312 as essential for transporter function. According to the structural model, residues D72, D201, and E312 may bind K+, whereas residues G67, Y70, and G71 may shape the selective filter for K+, which resembles that of K+shaker-like channels. In addition, we show that phosphorylation of residue S35 by AtCIPK23 is required for reaching maximal transport activity. Serial deletions of the AtHAK5 C-terminus disclosed the presence of an autoinhibitory domain located between residues 571 and 633 together with an AtCIPK23-dependent activation domain downstream of position 633. Presumably, autoinhibition of AtHAK5 is counteracted by phosphorylation of S35 by AtCIPK23. Our results provide a molecular model for K+ transport and describe CIPK-CBL-mediated regulation of plant HAK transporters. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|