1SQ0

Crystal Structure of the Complex of the Wild-type Von Willebrand Factor A1 domain and Glycoprotein Ib alpha at 2.6 Angstrom Resolution

DOI: 10.2210/pdb1SQ0/pdb

Classification: BLOOD CLOTTING
Organism(s): Homo sapiens
Expression System: Escherichia coli BL21(DE3), Cricetulus griseus
Mutation(s): Yes

Deposited: 2004-03-17 Released: 2004-04-13
Deposition Author(s): Dumas, J.J., Kumar, R., McDonagh, T., Sullivan, F., Stahl, M.L., Somers, W.S., Mosyak, L.

Experimental Data Snapshot

Method: X-RAY DIFFRACTION
Resolution: 2.60 Å
R-Value Free: 0.239
R-Value Work: 0.190
R-Value Observed: 0.190

wwPDB Validation 3D Report Full Report

This is version 1.2 of the entry. See complete history.

Literature

Crystal structure of the wild-type von Willebrand factor A1-glycoprotein Ibalpha complex reveals conformation differences with a complex bearing von Willebrand disease mutations

Dumas, J.J., Kumar, R., McDonagh, T., Sullivan, F., Stahl, M.L., Somers, W.S., Mosyak, L.

(2004) J Biol Chem 279: 23327-23334

PubMed: 15039442 Search on PubMed
DOI: 10.1074/jbc.M401659200
Primary Citation of Related Structures:
1SQ0

PubMed Abstract:

The adhesion of platelets to the subendothelium of blood vessels at sites of vascular injury under high shear conditions is mediated by a direct interaction between the platelet receptor glycoprotein Ibalpha (GpIbalpha) and the A1 domain of the von Willebrand factor (VWF). Here we report the 2.6-A crystal structure of a complex comprised of the extracellular domain of GpIbalpha and the wild-type A1 domain of VWF. A direct comparison of this structure to a GpIbalpha-A1 complex containing "gain-of-function" mutations, A1-R543Q and GpIbalpha-M239V, reveals specific structural differences between these complexes at sites near the two GpIbalpha-A1 binding interfaces. At the smaller interface, differences in interaction show that the alpha1-beta2 loop of A1 serves as a conformational switch, alternating between an open alpha1-beta2 isomer that allows faster dissociation of GpIbalpha-A1, as observed in the wild-type complex, and an extended isomer that favors tight association as seen in the complex containing A1 with a type 2B von Willebrand Disease (VWD) mutation associated with spontaneous binding to GpIbalpha. At the larger interface, differences in interaction associated with the GpIbalpha-M239V platelet-type VWD mutation are minor and localized but feature discrete gamma-turn conformers at the loop end of the beta-hairpin structure. The beta-hairpin, stabilized by a strong classic gamma-turn as seen in the mutant complex, relates to the increased affinity of A1 binding, and the beta-hairpin with a weak inverse gamma-turn observed in the wild-type complex corresponds to the lower affinity state of GpIbalpha. These findings provide important details that add to our understanding of how both type 2B and platelet-type VWD mutations affect GpIbalpha-A1 binding affinity.

Related Citations:

Crystal Structure of the GpIb(alpha)-Thrombin Complex Essential for Platelet Aggregation
Dumas, J.J., Kumar, R., Seehra, J., Somers, W.S., Mosyak, L.
(2003) Science 301: 222

Organizational Affiliation:

Department of Chemical and Screening Sciences, Wyeth, Cambridge, Massachusetts 02140, USA.

Macromolecules

Find similar proteins by:

(by identity cutoff) | Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Von Willebrand factor (vWF) [Contains: Von Willebrand antigen II]	A	214	Homo sapiens	Mutation(s): 1 Gene Names: VWF, F8VWF
Find proteins for P04275 (Homo sapiens) Explore P04275 Go to UniProtKB: P04275
NIH Common Fund Data Resources
PHAROS: P04275 GTEx: ENSG00000110799
Protein Feature View Expand
Reference Sequence

Find similar proteins by:

(by identity cutoff) | Structure

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Platelet glycoprotein Ib alpha chain (Glycoprotein Ibalpha) (GP-Ib alpha) (GPIbA) (GPIb-alpha) (CD42B-alpha) (CD42B) [Contains: Glycocalicin]	B	288	Homo sapiens	Mutation(s): 0 Gene Names: GP1BA
Find proteins for P07359 (Homo sapiens) Explore P07359 Go to UniProtKB: P07359
NIH Common Fund Data Resources
PHAROS: P07359 GTEx: ENSG00000185245
Protein Feature View Expand
Reference Sequence