PDBsum entry: 2v76

Protein-binding

PDB id: 2v76

Contents

Protein chains

99 a.a. *

102 a.a. *

Ligands

PGE ×4

SO4 ×4

EDO

GOL

Waters ×387

* Residue conservation analysis

PDB id:

2v76

Name:

Protein-binding

Title:

Crystal structure of the human dok1 ptb domain

Structure:

Docking protein 1. Chain: a, b, c, d. Fragment: ptb domain, residues 152-256. Synonym: downstream of tyrosine kinase 1, p62, dok, pp62, human dok1 ptb. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606

Resolution:

1.60Å R-factor: 0.190 R-free: 0.224

Authors:

C.L.Oxley,N.J.Anthis,E.D.Lowe,I.D.Campbell,K.L.Wegener

Key ref:

C.L.Oxley et al. (2008). An integrin phosphorylation switch: the effect of beta3 integrin tail phosphorylation on Dok1 and talin binding. J Biol Chem, 283, 5420-5426. PubMed id: 18156175 DOI: 10.1074/jbc.M709435200

Date:

26-Jul-07 Release date: 08-Jan-08

Protein chain

Q99704  (DOK1_HUMAN) -  Docking protein 1

Seq: 481 a.a.

Struc: 99 a.a.*

Protein chains

Q99704  (DOK1_HUMAN) -  Docking protein 1

Seq: 481 a.a.

Struc: 102 a.a.

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

 Gene Ontology (GO) functional annotation 

• Biochemical function: insulin receptor binding (1 term)

DOI no: 10.1074/jbc.M709435200

J Biol Chem 283:5420-5426 (2008)

PubMed id: 18156175

An integrin phosphorylation switch: the effect of beta3 integrin tail phosphorylation on Dok1 and talin binding.

C.L.Oxley, N.J.Anthis, E.D.Lowe, I.Vakonakis, I.D.Campbell, K.L.Wegener.

ABSTRACT

Integrins play a fundamental role in cell migration and adhesion; knowledge of how they are regulated and controlled is vital for understanding these processes. Recent work showed that Dok1 negatively regulates integrin activation, presumably by competition with talin. To understand how this occurs, we used NMR spectroscopy and x-ray crystallography to investigate the molecular details of interactions with integrins. The binding affinities of beta3 integrin tails for the Dok1 and talin phosphotyrosine binding domains were quantified using 15N-1H hetero-nuclear single quantum correlation titrations, revealing that the unphosphorylated integrin tail binds more strongly to talin than Dok1. Chemical shift mapping showed that unlike talin, Dok1 exclusively interacts with the canonical NPXY motif of the beta3 integrin tail. Upon phosphorylation of Tyr 747 in the beta3 integrin tail, however, Dok1 then binds much more strongly than talin. Thus, we show that phosphorylation of Tyr 747 provides a switch for integrin ligand binding. This switch may represent an in vivo mechanism for control of integrin receptor activation. These results have implications for the control of integrin signaling by proteins containing phosphotyrosine binding domains.

Selected figure(s)

Figure 1.
FIGURE 1. NMR titration studies using the ^15N-labeled full-length β3 integrin tail. A, a weighted shift map (see "Experimental Procedures") of induced chemical shift changes observed in ^15N-^1H HSQC spectra upon the addition of Dok1 PTB domain to the ^15N-labeled β3 integrin tail. B, averaged normalized weighted shifts, plotted against protein concentration, for full-length β3 integrin titrations with Dok1 and talin PTB domains. Error bars indicate the standard deviations for each titration point. Dissociation constants, K[d], calculated from the curves, are also shown.

Figure 4.
FIGURE 4. Dok1 PTB binding to the phosphorylatedβ3 integrin tail is mainly mediated by two conserved arginines. A, electron density map shown at 1.6 Å resolution covering Arg^222, Arg^207, and a sulfate molecule. The prefix h signifies human sequences, whereas c signifies chicken. B, model of the Dok1 PTB domain complexed with a peptide of the Tyr^747-phosphorylated β3 integrin tail. C, sequence alignment of PTB domains belonging to the IRS-like group (29).

The above figures are reprinted by permission from the ASBMB: J Biol Chem (2008, 283, 5420-5426) copyright 2008.

Figures were selected by the author.