3AUW

Cytoplasmic domain of inward rectifier potassium channel Kir3.2 in complex with cadmium

Summary for 3AUW

• Entry DOI: 10.2210/pdb3auw/pdb
• Related: 2e4f 3agw
• Descriptor: Potassium inwardly-rectifying channel, subfamily J, member 6, CADMIUM ION, MAGNESIUM ION, ... (6 entities in total)
• Functional Keywords: immunogloblin-like fold, ion transport, g protein beta gamma subunits, transport protein
• Biological source: Mus musculus (mouse); More
• Cellular location: Membrane ; Multi-pass membrane protein : Q0VB45 Q0VB45
• Total number of polymer chains: 4
• Total formula weight: 47899.56

Authors

Inanobe, A.,Kurachi, Y. (deposition date: 2011-02-17, release date: 2011-10-05, Last modification date: 2024-03-13)

Primary citation

Inanobe, A.,Matsuura, T.,Nakagawa, A.,Kurachi, Y.
Inverse agonist-like action of cadmium on G-protein-gated inward-rectifier K(+) channels
Biochem.Biophys.Res.Commun., 407:366-371, 2011

PubMed Abstract: The gate at the pore-forming domain of potassium channels is allosterically controlled by a stimulus-sensing domain. Using Cd²(+) as a probe, we examined the structural elements responsible for gating in an inward-rectifier K(+) channel (Kir3.2). One of four endogenous cysteines facing the cytoplasm contributes to a high-affinity site for inhibition by internal Cd²(+). Crystal structure of its cytoplasmic domain in complex with Cd²(+) reveals that octahedral coordination geometry supports the high-affinity binding. This mode of action causes the tethering of the N-terminus to CD loop in the stimulus-sensing domain, suggesting that their conformational changes participate in gating and Cd²(+) inhibits Kir3.2 by trapping the conformation in the closed state like "inverse agonist".

PubMed: 21396912
DOI: 10.1016/j.bbrc.2011.03.025

Experimental method

X-RAY DIFFRACTION (3.56 Å)