2KQ6

The structure of the EF-hand domain of polycystin-2 suggests a mechanism for Ca2+-dependent regulation of polycystin-2 channel activity


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 80 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy and least restraint violations 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structure of the EF-hand domain of polycystin-2 suggests a mechanism for Ca2+-dependent regulation of polycystin-2 channel activity.

Petri, E.T.Celic, A.Kennedy, S.D.Ehrlich, B.E.Boggon, T.J.Hodsdon, M.E.

(2010) Proc.Natl.Acad.Sci.USA 107: 9176-9181

  • DOI: 10.1073/pnas.0912295107

  • PubMed Abstract: 
  • The C-terminal cytoplasmic tail of polycystin-2 (PC2/TRPP2), a Ca(2+)-permeable channel, is frequently mutated or truncated in autosomal dominant polycystic kidney disease. We have previously shown that this tail consists of three functional regions: ...

    The C-terminal cytoplasmic tail of polycystin-2 (PC2/TRPP2), a Ca(2+)-permeable channel, is frequently mutated or truncated in autosomal dominant polycystic kidney disease. We have previously shown that this tail consists of three functional regions: an EF-hand domain (PC2-EF, 720-797), a flexible linker (798-827), and an oligomeric coiled coil domain (828-895). We found that PC2-EF binds Ca(2+) at a single site and undergoes Ca(2+)-dependent conformational changes, suggesting it is an essential element of Ca(2+)-sensitive regulation of PC2 activity. Here we describe the NMR structure and dynamics of Ca(2+)-bound PC2-EF. Human PC2-EF contains a divergent non-Ca(2+)-binding helix-loop-helix (HLH) motif packed against a canonical Ca(2+)-binding EF-hand motif. This HLH motif may have evolved from a canonical EF-hand found in invertebrate PC2 homologs. Temperature-dependent steady-state NOE experiments and NMR R(1) and R(2) relaxation rates correlate with increased molecular motion in the EF-hand, possibly due to exchange between apo and Ca(2+)-bound states, consistent with a role for PC2-EF as a Ca(2+)-sensitive regulator. Structure-based sequence conservation analysis reveals a conserved hydrophobic surface in the same region, which may mediate Ca(2+)-dependent protein interactions. We propose that Ca(2+)-sensing by PC2-EF is responsible for the cooperative nature of PC2 channel activation and inhibition. Based on our results, we present a mechanism of regulation of the Ca(2+) dependence of PC2 channel activity by PC2-EF.


    Organizational Affiliation

    Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Polycystin-2
A
78Homo sapiensMutation(s): 0 
Gene Names: PKD2 (TRPP2)
Find proteins for Q13563 (Homo sapiens)
Go to Gene View: PKD2
Go to UniProtKB:  Q13563
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 80 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy and least restraint violations 
  • Olderado: 2KQ6 Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-05-12
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance