9X0B

Cryo-EM structure of AKT5 - WT

Summary for 9X0B

• Entry DOI: 10.2210/pdb9x0b/pdb
• EMDB information: 66431
• Descriptor: Probable potassium channel AKT5 (1 entity in total)
• Functional Keywords: tetramer, transport protein
• Biological source: Arabidopsis thaliana (thale cress)
• Total number of polymer chains: 4
• Total formula weight: 401800.97

Authors

Muraoka, Y.,Tanaka, Y.,Yokoyama, T.,Furuta, T.,Yamanashi, T.,Tsujii, M.,Tsubota, R.,Uozumi, N. (deposition date: 2025-09-30, release date: 2026-07-15, Last modification date: 2026-09-09)

Primary citation

Muraoka, Y.,Kobayashi, S.,Oskam, L.,Tateyama, M.,Masago, A.,Tanaka, Y.,Yokoyama, T.,Furuta, T.,Takase, H.,Tanudjaja, E.,Terashima, S.,Shimizukawa, H.,Yamanashi, T.,Saito, S.,Ijima, H.,Tanaka, M.,Miyamoto, A.,Kato, M.,Sato, K.,Tsujii, M.,Umezawa, T.,Quintero, F.J.,Rubio, F.,Kudla, J.,Ito, M.,Kubo, Y.,Ishimaru, Y.,Pierik, R.,Uozumi, N.
AKT5 is a bona fide potassium channel and controls petiole growth in Arabidopsis.
Sci Adv, 12:eaeh7630-eaeh7630, 2026

PubMed Abstract: Potassium ion (K) is essential for plant growth and development. Despite decades of study, the -type K channel AKT5 has remained functionally unassigned. Here, we report that AKT5 functions as a bona fide voltage-dependent K channel and serves as an essential regulator of petiole elongation. Structural analyses of AKT5 in a closed state and the AKT5-D403 variant in a pre-open state provide direct structural evidence for functional K channel activity. AKT5 assembled into a canonical tetramer with two-fold symmetry and, upon phosphorylation, operated as an inward-rectifying K channel activated at strongly hyperpolarized membrane potentials. AKT5 was predominantly expressed in young petioles, and loss of AKT5 function largely suppressed petiole elongation throughout the diurnal cycle, resulting in compact rosettes and reduced biomass under crowded growth conditions. These findings show that AKT5 is involved in a regulator of plant competitive growth and high-density performance.

PubMed: 42685185
DOI: 10.1126/sciadv.aeh7630

Experimental method

ELECTRON MICROSCOPY (3.62 Å)