Macromolecule Content

• Total Structure Weight: 15.64 kDa 
• Atom Count: 946 
• Residue Count: 119 
• Unique protein chains: 2

1KA7

SAP/SH2D1A bound to peptide n-Y-c

• DOI: 10.2210/pdb1KA7/pdb
• BMRB: 5211

• Classification: IMMUNE SYSTEM
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): Yes 


• Deposited: 2001-10-31 Released: 2001-11-07 
• Deposition Author(s): Hwang, P.M., Li, C., Morra, M., Lillywhite, J., Gertler, F., Terhorst, C., Kay, L.E., Pawson, T., Forman-Kay, J., Li, S.-C.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Submitted: 1 

Literature

A "three-pronged" binding mechanism for the SAP/SH2D1A SH2 domain: structural basis and relevance to the XLP syndrome.

Hwang, P.M., Li, C., Morra, M., Lillywhite, J., Muhandiram, D.R., Gertler, F., Terhorst, C., Kay, L.E., Pawson, T., Forman-Kay, J.D., Li, S.C.

(2002) EMBO J 21: 314-323

• PubMed: 11823424 
• DOI: 10.1093/emboj/21.3.314
• Primary Citation of Related Structures:  
  1KA7, 1KA6


• PubMed Abstract: 
  

The SH2 domain protein SAP/SH2D1A, encoded by the X-linked lymphoproliferative (XLP) syndrome gene, associates with the hematopoietic cell surface receptor SLAM in a phosphorylation-independent manner. By screening a repertoire of synthetic peptides, the specificity of SAP/SH2D1A has been mapped and a consensus sequence motif for binding identified, T/S-x-x-x-x-V/I, where x represents any amino acid. Remarkably, this motif contains neither a Tyr nor a pTyr residue, a hallmark of conventional SH2 domain-ligand interactions. The structures of the protein, determined by NMR, in complex with two distinct peptides provide direct evidence in support of a "three-pronged" binding mechanism for the SAP/SH2D1A SH2 domain in contrast to the "two-pronged" binding for conventional SH2 domains. Differences in the structures of the two complexes suggest considerable flexibility in the SH2 domain, as further confirmed and characterized by hydrogen exchange studies. The structures also explain binding defects observed in disease-causing SAP/SH2D1A mutants and suggest that phosphorylation-independent interactions mediated by SAP/SH2D1A likely play an important role in the pathogenesis of XLP.

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Organizational Affiliation: 

Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
SH2 DOMAIN PROTEIN 1A	A	128	Homo sapiens	Mutation(s): 0  Gene Names: SH2D1A, DSHP, SAP
Find proteins for O60880 (Homo sapiens) Explore O60880  Go to UniProtKB:  O60880
NIH Common Fund Data Resources
PHAROS:  O60880 GTEx:  ENSG00000183918

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
peptide n-Y-c	B	12	N/A	Mutation(s): 1
Find proteins for Q13291 (Homo sapiens) Explore Q13291  Go to UniProtKB:  Q13291
NIH Common Fund Data Resources
PHAROS:  Q13291 GTEx:  ENSG00000117090

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Submitted: 1 
• OLDERADO: 1KA7 Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2001-10-31 
• Released Date: 2001-11-07 
Deposition Author(s): Hwang, P.M., Li, C., Morra, M., Lillywhite, J., Gertler, F., Terhorst, C., Kay, L.E., Pawson, T., Forman-Kay, J., Li, S.-C.

Revision History 

• Version 1.0: 2001-11-07
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance