Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 4-mer - A1B1C1D1 Pseudo Symmetry: Asymmetric - C1 
Pseudo Stoichiometry: Hetero 4-mer - A2B1C1 

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

Macromolecule Content

• Total Structure Weight: 213.02 kDa 
• Atom Count: 13889 
• Modelled Residue Count: 1735 
• Deposited Residue Count: 1873 
• Unique protein chains: 4

4UQI

AP2 controls clathrin polymerization with a membrane-activated switch

• DOI: 10.2210/pdb4UQI/pdb

• Classification: ENDOCYTOSIS
• Organism(s): Rattus norvegicus, Homo sapiens, Mus musculus
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2014-06-23 Released: 2014-07-30 
• Deposition Author(s): Kelly, B.T., Graham, S.C., Liska, N., Dannhauser, P.N., Hoening, S., Ungewickell, E.J., Owen, D.J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.79 Å
• R-Value Free: 0.259 
• R-Value Work: 0.203 
• R-Value Observed: 0.206 

Literature

Clathrin Adaptors. Ap2 Controls Clathrin Polymerization with a Membrane-Activated Switch.

Kelly, B.T., Graham, S.C., Liska, N., Dannhauser, P.N., Honing, S., Ungewickell, E.J., Owen, D.J.

(2014) Science 345: 459

• PubMed: 25061211 
• DOI: 10.1126/science.1254836
• Primary Citation of Related Structures:  
  4UQI


• PubMed Abstract: 
  

Clathrin-mediated endocytosis (CME) is vital for the internalization of most cell-surface proteins. In CME, plasma membrane-binding clathrin adaptors recruit and polymerize clathrin to form clathrin-coated pits into which cargo is sorted. Assembly polypeptide 2 (AP2) is the most abundant adaptor and is pivotal to CME. Here, we determined a structure of AP2 that includes the clathrin-binding β2 hinge and developed an AP2-dependent budding assay. Our findings suggest that an autoinhibitory mechanism prevents clathrin recruitment by cytosolic AP2. A large-scale conformational change driven by the plasma membrane phosphoinositide phosphatidylinositol 4,5-bisphosphate and cargo relieves this autoinhibition, triggering clathrin recruitment and hence clathrin-coated bud formation. This molecular switching mechanism can couple AP2's membrane recruitment to its key functions of cargo and clathrin binding.

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Organizational Affiliation: 

Cambridge Institute for Medical Research (CIMR), Department of Clinical Biochemistry, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK. [e-mail] [e-mail].

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
AP-2 COMPLEX SUBUNIT ALPHA-2	A	628	Rattus norvegicus	Mutation(s): 0  Gene Names: Ap2a2, Adtab
Find proteins for P18484 (Rattus norvegicus) Explore P18484  Go to UniProtKB:  P18484

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
AP-2 COMPLEX SUBUNIT BETA	B	657	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: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
AP-2 COMPLEX SUBUNIT MU	C [auth M]	446	Rattus norvegicus	Mutation(s): 0  Gene Names: Ap2m1
Find proteins for P84092 (Rattus norvegicus) Explore P84092  Go to UniProtKB:  P84092

Entity ID: 4
Molecule	Chains	Sequence Length	Organism	Details	Image
AP-2 COMPLEX SUBUNIT SIGMA	D [auth S]	142	Mus musculus	Mutation(s): 0  Gene Names: Ap2s1, Ap17, Claps2
Find proteins for P62743 (Mus musculus) Explore P62743  Go to UniProtKB:  P62743
NIH Common Fund Data Resources
IMPC:  MGI:2141861

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
IHP	F [auth A]	INOSITOL HEXAKISPHOSPHATE C6 H18 O24 P6 IMQLKJBTEOYOSI-GPIVLXJGSA-N
CL	E [auth A]	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.79 Å
• R-Value Free: 0.259 
• R-Value Work: 0.203 
• R-Value Observed: 0.206 
• Space Group: P 3₁ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 121.3	α = 90
b = 121.3	β = 90
c = 259.37	γ = 120

Software Package:

Software Name	Purpose
REFMAC	refinement
XDS	data reduction
SCALA	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2014-06-23 
• Released Date: 2014-07-30 
Deposition Author(s): Kelly, B.T., Graham, S.C., Liska, N., Dannhauser, P.N., Hoening, S., Ungewickell, E.J., Owen, D.J.

Revision History  

• Version 1.0: 2014-07-30
  Type: Initial release
  
• Version 1.1: 2014-08-06
  Changes: Database references
• Version 1.2: 2020-10-07
  Changes: Derived calculations, Other, Structure summary