PDBsum entry 5khj

Transport protein

PDB id: 5khj

Contents

Protein chains

199 a.a.

Ligands

6SY ×2

Waters ×314

PDB id:

5khj

Name:

Transport protein

Title:

Hcn2 cnbd in complex with uridine-3', 5'-cyclic monophosphate (cump)

Structure:

Potassium/sodium hyperpolarization-activated cyclic nucleotide-gated channel 2. Chain: a, b. Fragment: unp residues 443-643. Synonym: brain cyclic nucleotide-gated channel 2,bcng-2, hyperpolarization-activated cation channel 1,hac-1. Engineered: yes

Source:

Mus musculus. Mouse. Organism_taxid: 10090. Gene: hcn2, bcng2, hac1. Expressed in: escherichia coli. Expression_system_taxid: 469008.

Resolution:

2.01Å R-factor: 0.185 R-free: 0.252

Authors:

L.C.T.Ng,I.Putrenko,V.Baronas,F.Van Petegem,E.A.Accili

Key ref:

L.C.T.Ng et al. (2016). Cyclic Purine and Pyrimidine Nucleotides Bind to the HCN2 Ion Channel and Variably Promote C-Terminal Domain Interactions and Opening. Structure, 24, 1629-1642. PubMed id: 27568927

Date:

14-Jun-16 Release date: 14-Sep-16

Protein chains

O88703  (HCN2_MOUSE) -  Potassium/sodium hyperpolarization-activated cyclic nucleotide-gated channel 2 from Mus musculus

Seq: 863 a.a.

Struc: 199 a.a.

Structure 24:1629-1642 (2016)

PubMed id: 27568927

Cyclic Purine and Pyrimidine Nucleotides Bind to the HCN2 Ion Channel and Variably Promote C-Terminal Domain Interactions and Opening.

L.C.T.Ng, I.Putrenko, V.Baronas, F.Van Petegem, E.A.Accili.

ABSTRACT

Cyclic AMP is thought to facilitate the opening of the HCN2 channel by binding to a C-terminal domain and promoting or inhibiting interactions between subunits. Here, we correlated the ability of cyclic nucleotides to promote interactions of isolated HCN2 C-terminal domains in solution with their ability to facilitate channel opening. Cyclic IMP, a cyclic purine nucleotide, and cCMP, a cyclic pyrimidine nucleotide, bind to a C-terminal domain containing the cyclic nucleotide-binding domain but, in contrast to other cyclic nucleotides examined, fail to promote its oligomerization, and produce only modest facilitation of opening of the full-length channel. Comparisons between ligand bound structures identify a region between the sixth and seventh β strands and the distal C helix as important for facilitation and tight binding. We propose that promotion of interactions between the C-terminal domains by a given ligand contribute to its ability to facilitate opening of the full-length channel.