8WFZ

AtGORK Full length 2

Summary for 8WFZ

• Entry DOI: 10.2210/pdb8wfz/pdb
• EMDB information: 37500
• Descriptor: Potassium channel GORK (1 entity in total)
• Functional Keywords: complex, protein, transport protein
• Biological source: Arabidopsis thaliana (Mouse-ear cress)
• Total number of polymer chains: 4
• Total formula weight: 378333.91

Authors

Chen, Y.H.,Li, Q.Y.,Qin, L.,Tang, L.H.,zhang, C.R. (deposition date: 2023-09-20, release date: 2024-12-04, Last modification date: 2025-10-29)

Primary citation

Li, Q.Y.,Qin, L.,Tang, L.H.,Zhang, C.R.,Huang, S.,Wang, K.,Zhang, G.H.,Hao, N.J.,Xiao, Q.,Niu, T.,Su, M.,Hedrich, R.,Chen, Y.H.
Structural and mechanistic insights into symmetry conversion in plant GORK K+ channel regulation.
Protein Cell, 2025

PubMed Abstract: GORK is a shaker-like potassium channel in plants that contains ankyrin (ANK) repeats. In guard cells, activation of GORK causes K+ efflux, reducing turgor pressure and closing stomata. However, how GORK is regulated remains largely elusive. Here, we solved the cryo-EM structure of Arabidopsis GORK, revealing an unusual symmetry reduction (from C4 to C2) feature within its tetrameric assembly. This symmetry reduction in GORK channel is driven by ANK dimerization, which disrupts the coupling between transmembrane helices and cytoplasmic domains, thus maintaining GORK in an autoinhibited state. Electrophysiological and structural analyses further confirmed that ANK dimerization inhibits GORK, and its removal restores C4 symmetry, converting GORK to an activatable state. This dynamic switching between C2 and C4 symmetry, mediated by ANK dimerization, presents a GORK target site that guard cells regulate to switch the plant K+ channel between inhibited and activatable states, thus controlling stomatal movement in response to environmental stimuli.

PubMed: 40996076
DOI: 10.1093/procel/pwaf067

Experimental method

ELECTRON MICROSCOPY (4.3 Å)