1BXX

MU2 ADAPTIN SUBUNIT (AP50) OF AP2 ADAPTOR (SECOND DOMAIN), COMPLEXED WITH TGN38 INTERNALIZATION PEPTIDE DYQRLN

• PDB DOI: https://doi.org/10.2210/pdb1BXX/pdb

• Classification: ENDOCYTOSIS/EXOCYTOSIS
• Organism(s): Rattus norvegicus, synthetic construct
• Expression System: Escherichia coli BL21
• Mutation(s): No 


• Deposited: 1998-10-08 Released: 1998-11-25 
• Deposition Author(s): Owen, D.J., Evans, P.R.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.70 Å
• R-Value Free: 0.325 
• R-Value Work: 0.263 
• R-Value Observed: 0.282 

Starting Model: experimental

Literature

A structural explanation for the recognition of tyrosine-based endocytotic signals.

Owen, D.J., Evans, P.R.

(1998) Science 282: 1327-1332

• PubMed: 9812899 
• DOI: https://doi.org/10.1126/science.282.5392.1327
• Primary Citation of Related Structures:  
  1BW8, 1BXX


• PubMed Abstract: 
  

  Many cell surface proteins are marked for endocytosis by a cytoplasmic sequence motif, tyrosine-X-X-(hydrophobic residue), that is recognized by the mu2 subunit of AP2 adaptors. Crystal structures of the internalization signal binding domain of mu2 complexed with the internalization signal peptides of epidermal growth factor receptor and the trans-Golgi network protein TGN38 have been determined at 2.7 angstrom resolution. The signal peptides adopted an extended conformation rather than the expected tight turn. Specificity was conferred by hydrophobic pockets that bind the tyrosine and leucine in the peptide. In the crystal, the protein forms dimers that could increase the strength and specificity of binding to dimeric receptors.

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Organizational Affiliation: 

Medical Research Council Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 33.57 kDa 
• Atom Count: 2,142 
• Modelled Residue Count: 262 
• Deposited Residue Count: 291 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN (AP50)	A	285	Rattus norvegicus	Mutation(s): 0
UniProt
Find proteins for P84092 (Rattus norvegicus) Explore P84092  Go to UniProtKB:  P84092

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN (TGN38 PEPTIDE)	B [auth P]	6	synthetic construct	Mutation(s): 0

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.70 Å
• R-Value Free: 0.325 
• R-Value Work: 0.263 
• R-Value Observed: 0.282 
• Space Group: P 6₄

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 125.26	α = 90
b = 125.26	β = 90
c = 73.79	γ = 120

Software Package:

Software Name	Purpose
REFMAC	refinement
MOSFLM	data reduction
CCP4	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 1998-11-25 
Deposition Author(s): Owen, D.J., Evans, P.R.

Revision History  

• Version 1.0: 1998-11-25
  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: 2018-05-30
  Changes: Data collection, Source and taxonomy, Structure summary
• Version 1.4: 2023-08-09
  Changes: Data collection, Database references, Refinement description