Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 58.31 kDa 
• Atom Count: 3526 
• Modelled Residue Count: 417 
• Deposited Residue Count: 528 
• Unique protein chains: 1

1QQG

CRYSTAL STRUCTURE OF THE PH-PTB TARGETING REGION OF IRS-1

• PDB DOI: 10.2210/pdb1QQG/pdb

• Classification: SIGNAL TRANSDUCTION
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1999-06-04 Released: 1999-08-01 
• Deposition Author(s): Dhe-Paganon, S., Shoelson, S.E.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 0.247 
• R-Value Work: 0.191 
• R-Value Observed: 0.191 

Literature

Crystal structure of the pleckstrin homology-phosphotyrosine binding (PH-PTB) targeting region of insulin receptor substrate 1.

Dhe-Paganon, S., Ottinger, E.A., Nolte, R.T., Eck, M.J., Shoelson, S.E.

(1999) Proc Natl Acad Sci U S A 96: 8378-8383

• PubMed: 10411883 
• DOI: 10.1073/pnas.96.15.8378
• Primary Citation of Related Structures:  
  1QQG


• PubMed Abstract: 
  

We have determined the crystal structure at 2.3-A resolution of an amino-terminal segment of human insulin receptor substrate 1 that encompasses its pleckstrin homology (PH) and phosphotyrosine binding (PTB) domains. Both domains adopt the canonical seven-stranded beta-sandwich PH domain fold. The domains are closely associated, with a 720-A(2) contact surface buried between them that appears to be stabilized by ionic, hydrophobic, and hydrogen bonding interactions. The nonconserved 46-residue linker between the domains is disordered. The PTB domain peptide binding site is fully exposed on the molecular surface, as is a large cationic patch at the base of the PH domain that is a likely binding site for the head groups of phosphatidylinositol phosphates. Binding assays confirm that phosphatidylinositol phosphates bind the PH domain, but not the PTB domain. Ligand binding to the PH domain does not alter PTB domain interactions, and vice versa. The structural and accompanying functional data illustrate how the two binding domains might act cooperatively to effectively increase local insulin receptor substrate 1 concentration at the membrane and transiently fix the receptor and substrate, to allow multiple phosphorylation reactions to occur during each union.

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Organizational Affiliation: 

Joslin Diabetes Center and the Department of Medicine, Harvard Medical School, Boston, MA 02215, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
INSULIN RECEPTOR SUBSTRATE 1	A, B	264	Homo sapiens	Mutation(s): 0  Gene Names: IRS1
UniProt & NIH Common Fund Data Resources
Find proteins for P35568 (Homo sapiens) Explore P35568  Go to UniProtKB:  P35568
PHAROS:  P35568

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 0.247 
• R-Value Work: 0.191 
• R-Value Observed: 0.191 
• Space Group: P 6₅

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 120.439	α = 90
b = 120.439	β = 90
c = 79.598	γ = 120

Software Package:

Software Name	Purpose
MLPHARE	phasing
X-PLOR	refinement
XDS	data reduction
AUTOMAR	data reduction

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1999-06-04 
• Released Date: 1999-08-01 
Deposition Author(s): Dhe-Paganon, S., Shoelson, S.E.

Revision History  

• Version 1.0: 1999-08-01
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2017-10-04
  Changes: Refinement description
• Version 1.4: 2018-01-31
  Changes: Experimental preparation