3FFK

Crystal structure of human Gelsolin domains G1-G3 bound to Actin


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Free: 0.273 
  • R-Value Work: 0.201 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Ca2+ binding by domain 2 plays a critical role in the activation and stabilization of gelsolin.

Nag, S.Ma, Q.Wang, H.Chumnarnsilpa, S.Lee, W.L.Larsson, M.Kannan, B.Hernandez-Valladares, M.Burtnick, L.D.Robinson, R.C.

(2009) Proc.Natl.Acad.Sci.USA 106: 13713-13718

  • DOI: 10.1073/pnas.0812374106
  • Primary Citation of Related Structures:  3FFN

  • PubMed Abstract: 
  • Gelsolin consists of six homologous domains (G1-G6), each containing a conserved Ca-binding site. Occupation of a subset of these sites enables gelsolin to sever and cap actin filaments in a Ca-dependent manner. Here, we present the structures of Ca- ...

    Gelsolin consists of six homologous domains (G1-G6), each containing a conserved Ca-binding site. Occupation of a subset of these sites enables gelsolin to sever and cap actin filaments in a Ca-dependent manner. Here, we present the structures of Ca-free human gelsolin and of Ca-bound human G1-G3 in a complex with actin. These structures closely resemble those determined previously for equine gelsolin. However, the G2 Ca-binding site is occupied in the human G1-G3/actin structure, whereas it is vacant in the equine version. In-depth comparison of the Ca-free and Ca-activated, actin-bound human gelsolin structures suggests G2 and G6 to be cooperative in binding Ca(2+) and responsible for opening the G2-G6 latch to expose the F-actin-binding site on G2. Mutational analysis of the G2 and G6 Ca-binding sites demonstrates their interdependence in maintaining the compact structure in the absence of calcium. Examination of Ca binding by G2 in human G1-G3/actin reveals that the Ca(2+) locks the G2-G3 interface. Thermal denaturation studies of G2-G3 indicate that Ca binding stabilizes this fragment, driving it into the active conformation. The G2 Ca-binding site is mutated in gelsolin from familial amyloidosis (Finnish-type) patients. This disease initially proceeds through protease cleavage of G2, ultimately to produce a fragment that forms amyloid fibrils. The data presented here support a mechanism whereby the loss of Ca binding by G2 prolongs the lifetime of partially activated, intermediate conformations in which the protease cleavage site is exposed.


    Organizational Affiliation

    Institute of Molecular and Cell Biology, ASTAR, 61 Biopolis Drive, Proteos, Singapore 138673.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
plasma gelsolin
A, D
377Homo sapiensGene Names: GSN
Find proteins for P06396 (Homo sapiens)
Go to Gene View: GSN
Go to UniProtKB:  P06396
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
actin, alpha skeletal muscle
B, E
377Oryctolagus cuniculusGene Names: ACTA1 (ACTA)
Find proteins for P68135 (Oryctolagus cuniculus)
Go to Gene View: ACTA1
Go to UniProtKB:  P68135
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ATP
Query on ATP

Download SDF File 
Download CCD File 
B, E
ADENOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O13 P3
ZKHQWZAMYRWXGA-KQYNXXCUSA-N
 Ligand Interaction
CA
Query on CA

Download SDF File 
Download CCD File 
A, B, D, E
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Free: 0.273 
  • R-Value Work: 0.201 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 102.179α = 90.00
b = 146.923β = 90.00
c = 148.301γ = 90.00
Software Package:
Software NamePurpose
PDB_EXTRACTdata extraction
AMoREphasing
SCALEPACKdata scaling
DENZOdata reduction
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-10-06
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Refinement description, Version format compliance
  • Version 1.2: 2017-11-01
    Type: Refinement description