7SQW

Structure of the KcsA-W67F mutant with the activation gate in the closed conformation

Summary for 7SQW

• Entry DOI: 10.2210/pdb7sqw/pdb
• Descriptor: Antibody Fragment, KcsA potassium channel, NONAN-1-OL, ... (6 entities in total)
• Functional Keywords: channel, fab complex, c-type inactivation, membrane protein
• Biological source: Mus musculus (Mouse); More
• Total number of polymer chains: 3
• Total formula weight: 58569.10

Authors

Cuello, L.G.,Labro, A.J. (deposition date: 2021-11-07, release date: 2022-10-12, Last modification date: 2024-10-23)

Primary citation

Coonen, L.,Martinez-Morales, E.,Van De Sande, D.V.,Snyders, D.J.,Cortes, D.M.,Cuello, L.G.,Labro, A.J.
The nonconducting W434F mutant adopts upon membrane depolarization an inactivated-like state that differs from wild-type Shaker-IR potassium channels.
Sci Adv, 8:eabn1731-eabn1731, 2022

PubMed Abstract: Voltage-gated K (Kv) channels mediate the flow of K across the cell membrane by regulating the conductive state of their activation gate (AG). Several Kv channels display slow C-type inactivation, a process whereby their selectivity filter (SF) becomes less or nonconductive. It has been proposed that, in the fast inactivation-removed Shaker-IR channel, the W434F mutation epitomizes the C-type inactivated state because it functionally accelerates this process. By introducing another pore mutation that prevents AG closure, P475D, we found a way to record ionic currents of the Shaker-IR-W434F-P475D mutant at hyperpolarized membrane potentials as the W434F-mutant SF recovers from its inactivated state. This W434F conductive state lost its high K over Na selectivity, and even NMDG can permeate, features not observed in a wild-type SF. This indicates that, at least during recovery from inactivation, the W434F-mutant SF transitions to a widened and noncationic specific conformation.

PubMed: 36112676
DOI: 10.1126/sciadv.abn1731

Experimental method

X-RAY DIFFRACTION (3.21 Å)