5HK7

Bacterial sodium channel pore, 2.95 Angstrom resolution

Summary for 5HK7

• Entry DOI: 10.2210/pdb5hk7/pdb
• Related: 5HJ8 5HK6 5HKD 5HKT 5HKU
• Descriptor: Ion transport protein, CHLORIDE ION, 2-{[(S)-(2-aminoethoxy)(hydroxy)phosphoryl]oxy}ethyl heptadecanoate, ... (5 entities in total)
• Functional Keywords: bacterial sodium channel pore, transport protein
• Biological source: Alkalilimnicola ehrlichii
• Total number of polymer chains: 4
• Total formula weight: 74345.77

Authors

Shaya, D.,Findeisen, F.,Rohaim, A.,Minor, D.L. (deposition date: 2016-01-14, release date: 2016-03-09, Last modification date: 2023-09-27)

Primary citation

Arrigoni, C.,Rohaim, A.,Shaya, D.,Findeisen, F.,Stein, R.A.,Nurva, S.R.,Mishra, S.,Mchaourab, H.S.,Minor, D.L.
Unfolding of a Temperature-Sensitive Domain Controls Voltage-Gated Channel Activation.
Cell, 164:922-936, 2016

PubMed Abstract: Voltage-gated ion channels (VGICs) are outfitted with diverse cytoplasmic domains that impact function. To examine how such elements may affect VGIC behavior, we addressed how the bacterial voltage-gated sodium channel (BacNa(V)) C-terminal cytoplasmic domain (CTD) affects function. Our studies show that the BacNa(V) CTD exerts a profound influence on gating through a temperature-dependent unfolding transition in a discrete cytoplasmic domain, the neck domain, proximal to the pore. Structural and functional studies establish that the BacNa(V) CTD comprises a bi-partite four-helix bundle that bears an unusual hydrophilic core whose integrity is central to the unfolding mechanism and that couples directly to the channel activation gate. Together, our findings define a general principle for how the widespread four-helix bundle cytoplasmic domain architecture can control VGIC responses, uncover a mechanism underlying the diverse BacNa(V) voltage dependencies, and demonstrate that a discrete domain can encode the temperature-dependent response of a channel.

PubMed: 26919429
DOI: 10.1016/j.cell.2016.02.001

Experimental method

X-RAY DIFFRACTION (2.95 Å)