1N9Z

INTEGRIN ALPHA M I DOMAIN MUTANT


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Free: 0.278 
  • R-Value Work: 0.242 
  • R-Value Observed: 0.247 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Engineered allosteric mutants of the integrin alphaMbeta2 I domain: structural and functional studies

McCleverty, C.J.Liddington, R.C.

(2003) Biochem J 372: 121-127

  • DOI: 10.1042/BJ20021273
  • Primary Citation of Related Structures:  
    1MF7, 1N9Z, 1NA5

  • PubMed Abstract: 
  • The alpha-I domain, found in the alpha-subunit of the leucocyte integrins such as alphaMbeta2 and alphaLbeta2, switches between the open and closed tertiary conformations, reflecting the high- and low-affinity ligand-binding states of the integrin that are required for regulated cell adhesion and migration ...

    The alpha-I domain, found in the alpha-subunit of the leucocyte integrins such as alphaMbeta2 and alphaLbeta2, switches between the open and closed tertiary conformations, reflecting the high- and low-affinity ligand-binding states of the integrin that are required for regulated cell adhesion and migration. In the present study we show, by using point mutations and engineered disulphide bonds, that ligand affinity can be reduced or increased allosterically by altering the equilibrium between the closed and open states. We determined equilibrium constants for the binding of two ligands, fibrinogen and intercellular cell-adhesion molecule 1, to the alphaM-I domain by surface plasmon resonance, and determined crystal structures of a low-affinity mutant. Locking the domain in the open conformation increases affinity by a factor of no greater than 10, consistent with a closely balanced equilibrium between the two conformations in the absence of ligand. This behaviour contrasts with that of the unliganded alphaL-I domain, for which the equilibrium lies strongly in favour of the closed conformation. These results suggest significant differences in the way the parent integrins regulate I domain conformation and hence ligand affinity.


    Organizational Affiliation

    The Burnham Institute, 10901 North Torrey Pines Rd, La Jolla, CA 92037, U.S.A.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Integrin alpha-M A192Homo sapiensMutation(s): 3 
Gene Names: ITGAM OR CR3A OR CD11BITGAMCD11BCR3A
Find proteins for P11215 (Homo sapiens)
Explore P11215 
Go to UniProtKB:  P11215
NIH Common Fund Data Resources
PHAROS:  P11215
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MG
Query on MG

Download Ideal Coordinates CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Free: 0.278 
  • R-Value Work: 0.242 
  • R-Value Observed: 0.247 
  • Space Group: P 43
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 44.22α = 90
b = 44.22β = 90
c = 99.91γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
AMoREphasing
CNSrefinement

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2003-05-20
    Type: Initial release
  • Version 1.1: 2008-04-28
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance