PDBsum entry 1s1g

Transport protein

PDB id: 1s1g

Contents

Protein chains

107 a.a. *

Metals

_ZN ×2

Waters ×28

* Residue conservation analysis

PDB id:

1s1g

Name:

Transport protein

Title:

Crystal structure of kv4.3 t1 domain

Structure:

Potassium voltage-gated channel subfamily d member 3. Chain: a, b. Fragment: kv4.3t1 (residue 29-143, sws q9uk17). Synonym: potassium channel kv4.3. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Gene: kcnd3. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008.

Biol. unit:

Tetramer (from PDB file)

Resolution:

2.60Å R-factor: 0.228 R-free: 0.273

Authors:

R.H.Scannevin,K.W.Wang,F.Jow,J.Megules,D.C.Kopsco,W.Edris, K.C.Carroll,Q.Lu,W.X.Xu,Z.B.Xu,A.H.Katz,S.Olland,L.Lin,M.Taylor, M.Stahl,K.Malakian,W.Somers,L.Mosyak,M.R.Bowlby,P.Chanda,K.J.Rhodes

Key ref:

R.H.Scannevin et al. (2004). Two N-terminal domains of Kv4 K(+) channels regulate binding to and modulation by KChIP1. Neuron, 41, 587-598. PubMed id: 14980207 DOI: 10.1016/S0896-6273(04)00049-2

Date:

06-Jan-04 Release date: 23-Mar-04

Protein chains

Q9UK17  (KCND3_HUMAN) -  Potassium voltage-gated channel subfamily D member 3 from Homo sapiens

Seq: 655 a.a.

Struc: 107 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1016/S0896-6273(04)00049-2

Neuron 41:587-598 (2004)

PubMed id: 14980207

Two N-terminal domains of Kv4 K(+) channels regulate binding to and modulation by KChIP1.

R.H.Scannevin, K.Wang, F.Jow, J.Megules, D.C.Kopsco, W.Edris, K.C.Carroll, Q.Lü, W.Xu, Z.Xu, A.H.Katz, S.Olland, L.Lin, M.Taylor, M.Stahl, K.Malakian, W.Somers, L.Mosyak, M.R.Bowlby, P.Chanda, K.J.Rhodes.

ABSTRACT

The family of calcium binding proteins called KChIPs associates with Kv4 family K(+) channels and modulates their biophysical properties. Here, using mutagenesis and X-ray crystallography, we explore the interaction between Kv4 subunits and KChIP1. Two regions in the Kv4.2 N terminus, residues 7-11 and 71-90, are necessary for KChIP1 modulation and interaction with Kv4.2. When inserted into the Kv1.2 N terminus, residues 71-90 of Kv4.2 are also sufficient to confer association with KChIP1. To provide a structural framework for these data, we solved the crystal structures of Kv4.3N and KChIP1 individually. Taken together with the mutagenesis data, the individual structures suggest that that the Kv4 N terminus is required for stable association with KChIP1, perhaps through a hydrophobic surface interaction, and that residues 71-90 in Kv4 subunits form a contact loop that mediates the specific association of KChIPs with Kv4 subunits.

Selected figure(s)

Figure 1.
Figure 1. The Proximal N Terminus of Kv4.2 Is Necessary for Modulation by KChIP1Currents were recorded from oocytes injected with the indicated Kv4.2 wild-type or deletion mutant RNA in the presence or absence of KChIP1. The left side panels depict representative current traces measured at +50 mV for 1 s from holding potential at −80 mV, and the right side of each panel depicts normalized recovery from inactivation fitted with a single exponential function for Kv4.2 alone (open circle) and for Kv4.2 co-expressed with KChIP1 (closed circle).(A) Wild-type Kv4.2; (B) Kv4.2Δ2–21; (C) Kv4.2Δ2–11; (D) Kv4.2Δ2–6; (E) Kv4.2Δ7–11; (F) Kv4.2(WGEFA) multiple point mutant, contains mutations in Kv4.2 7–11 region.

Figure 2.
Figure 2. Residues 71–90 of Kv4.2N Are Critical for KChIP1 ModulationCurrents were recorded as in Figure 1. The left side of all panels depicts representative current traces from oocytes injected with indicated Kv4.2 RNA in the presence or absence of KChIP1. Right side of each panel depicts normalized recovery from inactivation fitted with a single exponential function for Kv4.2 alone (open circle) and for Kv4.2 co-expressed with KChIP1 (closed circle).(A) Kv4.2Δ161–180; (B) Kv4.2Δ71–90; (C) Kv4.2 (F74R) single point mutant.

The above figures are reprinted by permission from Cell Press: Neuron (2004, 41, 587-598) copyright 2004.

Figures were selected by an automated process.