4HPF

Structure of the human SLO3 gating ring


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.4 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.247 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Functional and structural analysis of the human SLO3 pH- and voltage-gated K+ channel.

Leonetti, M.D.Yuan, P.Hsiung, Y.Mackinnon, R.

(2012) Proc.Natl.Acad.Sci.USA 109: 19274-19279

  • DOI: 10.1073/pnas.1215078109

  • PubMed Abstract: 
  • The activation of eukaryotic SLO K(+) channels by intracellular cues, mediated by a cytoplasmic structure called the gating ring, is central to their physiological roles. SLO3 channels are exclusively expressed in mammalian sperm, where variations of ...

    The activation of eukaryotic SLO K(+) channels by intracellular cues, mediated by a cytoplasmic structure called the gating ring, is central to their physiological roles. SLO3 channels are exclusively expressed in mammalian sperm, where variations of intracellular pH are critical to cellular function. Previous studies primarily focused on the mouse SLO3 orthologue and revealed that, in murine sperm, SLO3 mediates a voltage- and alkalization-activated K(+) current essential to male fertility. Here we investigate the activation of the human SLO3 channel by intracellular pH at the functional and structural level. By using electrophysiology in a heterologous system, we show that human SLO3 opens upon intracellular pH increase and that its expression and functional properties are modulated by LRRC52, a testis-specific accessory subunit. We next present the crystal structure of the human SLO3 gating ring. Comparison with the known structures of the corresponding domain from SLO1, a Ca(2+)-activated homologue, suggests that the SLO3 gating ring structure may represent an open state. Together, these results present insights into the function of a protein expected to be critical for human reproduction and provide a framework to study the mechanism of pH gating in SLO3 channels.


    Organizational Affiliation

    Laboratory of Molecular Neurobiology and Biophysics and Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Potassium channel subfamily U member 1
A, B
722Homo sapiensMutation(s): 0 
Gene Names: KCNU1 (KCNMA3, KCNMC1, SLO3)
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Channels: Potassium, Sodium, & Proton Ion-Selective
Protein: 
SLO3 K+ Channel pH-sensitive Gating Ring
Find proteins for A8MYU2 (Homo sapiens)
Go to Gene View: KCNU1
Go to UniProtKB:  A8MYU2
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.4 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.247 
  • Space Group: I 2 2 2
Unit Cell:
Length (Å)Angle (°)
a = 124.540α = 90.00
b = 157.940β = 90.00
c = 249.010γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
DENZOdata reduction
REFMACrefinement
MOLREPphasing
HKL-2000data collection
PDB_EXTRACTdata extraction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-11-07
    Type: Initial release
  • Version 1.1: 2012-12-05
    Type: Database references
  • Version 1.2: 2017-08-09
    Type: Refinement description, Source and taxonomy
  • Version 1.3: 2017-11-15
    Type: Refinement description