Biological Assembly 1  

 3D View: Structure | Electron Density

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

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

Macromolecule Content

• Total Structure Weight: 31.73 kDa 
• Atom Count: 2028 
• Residue Count: 250 
• Unique protein chains: 2

2IV8

beta appendage in complex with b-arrestin peptide

• DOI: 10.2210/pdb2IV8/pdb

• Classification: ENDOCYTOSIS/REGULATOR
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21
• Mutation(s): No 


• Deposited: 2006-06-08 Released: 2007-06-12 
• Deposition Author(s): Ford, M.G.J., Schmid, E.M., McMahon, H.T.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.80 Å
• R-Value Free: 0.369 
• R-Value Work: 0.213 
• R-Value Observed: 0.220 

Literature

Role of the Ap2 Beta-Appendage Hub in Recruiting Partners for Clathrin-Coated Vesicle Assembly.

Schmid, E.M., Ford, M.G.J., Burtey, A., Praefcke, G.J.K., Peak-Chew, S., Mills, I.G., Benmerah, A., Mcmahon, H.T.

(2006) PLoS Biol 4: E262

• PubMed: 16903783 
• DOI: 10.1371/journal.pbio.0040262
• Primary Citation of Related Structures:  
  2IV9, 2IV8


• PubMed Abstract: 
  

Adaptor protein complex 2 alpha and beta-appendage domains act as hubs for the assembly of accessory protein networks involved in clathrin-coated vesicle formation. We identify a large repertoire of beta-appendage interactors by mass spectrometry. These interact with two distinct ligand interaction sites on the beta-appendage (the "top" and "side" sites) that bind motifs distinct from those previously identified on the alpha-appendage. We solved the structure of the beta-appendage with a peptide from the accessory protein Eps15 bound to the side site and with a peptide from the accessory cargo adaptor beta-arrestin bound to the top site. We show that accessory proteins can bind simultaneously to multiple appendages, allowing these to cooperate in enhancing ligand avidities that appear to be irreversible in vitro. We now propose that clathrin, which interacts with the beta-appendage, achieves ligand displacement in vivo by self-polymerisation as the coated pit matures. This changes the interaction environment from liquid-phase, affinity-driven interactions, to interactions driven by solid-phase stability ("matricity"). Accessory proteins that interact solely with the appendages are thereby displaced to areas of the coated pit where clathrin has not yet polymerised. However, proteins such as beta-arrestin (non-visual arrestin) and autosomal recessive hypercholesterolemia protein, which have direct clathrin interactions, will remain in the coated pits with their interacting receptors.

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Organizational Affiliation: 

Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
AP-2 COMPLEX SUBUNIT BETA-1	A	238	Homo sapiens	Mutation(s): 0  Gene Names: AP2B1, ADTB2, CLAPB1
Find proteins for P63010 (Homo sapiens) Explore P63010  Go to UniProtKB:  P63010
NIH Common Fund Data Resources
PHAROS  P63010 GTEx  ENSG00000006125

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
BETA-ARRESTIN-1	P, Q	20	Homo sapiens	Mutation(s): 0  Gene Names: ARRB1, ARR1
Find proteins for P49407 (Homo sapiens) Explore P49407  Go to UniProtKB:  P49407
NIH Common Fund Data Resources
PHAROS  P49407 GTEx  ENSG00000137486

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.80 Å
• R-Value Free: 0.369 
• R-Value Work: 0.213 
• R-Value Observed: 0.220 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 36.952	α = 90
b = 35.484	β = 90
c = 190.624	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
MOSFLM	data reduction
SCALA	data scaling
PHASER	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2006-06-08 
• Released Date: 2007-06-12 
Deposition Author(s): Ford, M.G.J., Schmid, E.M., McMahon, H.T.

Revision History 

• Version 1.0: 2007-06-12
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Advisory, Version format compliance