5AAR

Structure of the ankyrin domain of an Arabidopsis Thaliana potassium channel

Summary for 5AAR

• Entry DOI: 10.2210/pdb5aar/pdb
• Descriptor: POTASSIUM CHANNEL AKT1, MAGNESIUM ION (3 entities in total)
• Functional Keywords: transport protein, ankyrin, abiotic stress, ion homeostasis
• Biological source: ARABIDOPSIS THALIANA (THALE CRESS)
• Total number of polymer chains: 1
• Total formula weight: 20417.65

Authors

Chaves-Sanjuan, A.,Sanchez-Barrena, M.J.,Albert, A. (deposition date: 2015-07-28, release date: 2016-08-24, Last modification date: 2024-01-10)

Primary citation

Sanchez-Barrena, M.J.,Chaves-Sanjuan, A.,Raddatz, N.,Mendoza, I.,Cortes, A.,Gago, F.,Gonzalez-Rubio, J.M.,Benavente, J.L.,Quintero, F.J.,Pardo, J.M.,Albert, A.
Recognition and activation of the plant AKT1 potassium channel by the kinase CIPK23.
Plant Physiol., 2020

PubMed Abstract: Plant growth largely depends on the maintenance of adequate intracellular levels of potassium (K). The families of 10 Calcineurin B-Like (CBL) calcium sensors and 26 CBL-Interacting Protein Kinases (CIPKs) of Arabidopsis () decode the calcium signals elicited by environmental inputs to regulate different ion channels and transporters involved in the control of K fluxes by phosphorylation-dependent and -independent events. However, the detailed molecular mechanisms governing target specificity require investigation. Here, we show that the physical interaction between CIPK23 and the noncanonical ankyrin domain in the cytosolic side of the inward-rectifier K channel AKT1 regulates kinase docking and channel activation. Point mutations on this domain specifically alter binding to CIPK23, enhancing or impairing the ability of CIPK23 to regulate channel activity. Our data demonstrate the relevance of this protein-protein interaction that contributes to the formation of a complex between CIPK23/CBL1 and AKT1 in the membrane for the proper regulation of K transport.

PubMed: 32015077
DOI: 10.1104/pp.19.01084

Experimental method

X-RAY DIFFRACTION (1.87 Å)