2IIM

SH3 Domain of Human Lck


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1 Å
  • R-Value Free: 0.153 
  • R-Value Work: 0.132 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal structure analysis and solution studies of human Lck-SH3; zinc-induced homodimerization competes with the binding of proline-rich motifs.

Romir, J.Lilie, H.Egerer-Sieber, C.Bauer, F.Sticht, H.Muller, Y.A.

(2007) J.Mol.Biol. 365: 1417-1428

  • DOI: 10.1016/j.jmb.2006.10.058

  • PubMed Abstract: 
  • In cytosolic Src-type tyrosine kinases the Src-type homology 3 (SH3) domain binds to an internal proline-rich motif and the presence or the absence of this interaction modulates the kinase enzymatic activity. The Src-type kinase Lck plays an importan ...

    In cytosolic Src-type tyrosine kinases the Src-type homology 3 (SH3) domain binds to an internal proline-rich motif and the presence or the absence of this interaction modulates the kinase enzymatic activity. The Src-type kinase Lck plays an important role during T-cell activation and development, since it phosphorylates the T-cell antigen receptor in an early step of the activation pathway. We have determined the crystal structure of the SH3 domain from Lck kinase at a near-atomic resolution of 1.0 A. Unexpectedly, the Lck-SH3 domain forms a symmetrical homodimer in the crystal and the dimer comprises two identical zinc-binding sites in the interface. The atomic interactions formed across the dimer interface resemble strikingly those observed between SH3 domains and their canonical proline-rich ligands, since almost identical residues participate in both contacts. Ultracentrifugation experiments confirm that in the presence of zinc ions, the Lck-SH3 domain also forms dimers in solution. The Zn(2+) dissociation constant from the Lck-SH3 dimer is estimated to be lower than 100 nM. Moreover, upon addition of a proline-rich peptide with a sequence corresponding to the recognition segment of the herpesviral regulatory protein Tip, competition between zinc-induced homodimerization and binding of the peptide can be detected by both fluorescence spectroscopy and analytical ultracentrifugation. These results suggest that in vivo, too, competition between Lck-SH3 homodimerization and binding of regulatory proline-rich sequence motifs possibly represents a novel mechanism by which kinase activity is modulated. Because the residues that form the zinc-binding site are highly conserved among Lck orthologues but not in other Src-type kinases, the mechanism might be peculiar to Lck and to its role in the initial steps of T-cell activation.


    Organizational Affiliation

    Lehrstuhl für Biotechnik, Institut für Biologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Proto-oncogene tyrosine-protein kinase LCK
A
62Homo sapiensMutation(s): 0 
Gene Names: LCK
EC: 2.7.10.2
Find proteins for P06239 (Homo sapiens)
Go to Gene View: LCK
Go to UniProtKB:  P06239
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
A
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
CA
Query on CA

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Download CCD File 
A
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
PG4
Query on PG4

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Download CCD File 
A
TETRAETHYLENE GLYCOL
C8 H18 O5
UWHCKJMYHZGTIT-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1 Å
  • R-Value Free: 0.153 
  • R-Value Work: 0.132 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 50.310α = 90.00
b = 50.310β = 90.00
c = 46.370γ = 120.00
Software Package:
Software NamePurpose
AMoREphasing
SHELXL-97refinement
XDSdata scaling
HKL-2000data collection
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-11-07
    Type: Initial release
  • Version 1.1: 2008-05-01
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance