Phosphotyrosine-binding domain

Phosphotyrosine-binding domain
Structure of the PTB domain of tensin1.[1]
Identifiers
Symbol PTB
Pfam PF08416
InterPro IPR013625
PTB domain (IRS-1 type)
irs-1 ptb domain complexed with a il-4 receptor phosphopeptide, nmr, minimized average structure
Identifiers
Symbol IRS
Pfam PF02174
InterPro IPR002404
SMART PTBI
SCOP 1cli

In molecular biology, Phosphotyrosine-binding domains are protein domains which bind to phosphotyrosine.

The phosphotyrosine-binding domain (PTB, also phosphotyrosine-interaction or PI domain) in the protein tensin tends to be found at the C-terminus. Tensin is a multi-domain protein that binds to actin filaments and functions as a focal-adhesion molecule (focal adhesions are regions of plasma membrane through which cells attach to the extracellular matrix). Human tensin has actin-binding sites, an SH2 (Pfam PF00017) domain and a region similar to the tumour suppressor PTEN.[2] The PTB domain interacts with the cytoplasmic tails of beta integrin by binding to an NPXY motif.[3]

The phosphotyrosine-binding domain of insulin receptor substrate-1 is not related to the phosphotyrosine-binding domain of tensin. Insulin receptor substrate-1 proteins contain both a pleckstrin homology domain and a phosphotyrosine binding (PTB) domain. The PTB domains facilitate interaction with the activated tyrosine-phosphorylated insulin receptor. The PTB domain is situated towards the N terminus. Two arginines in this domain are responsible for hydrogen bonding phosphotyrosine residue]s on a Ac-LYASSNPApY-NH2 peptide in the juxtamembrane region of the insulin receptor. Further interactions via `bridged' water molecules are coordinated by residues an Asn and a Ser residue .[4] The PTB domain has a compact, 7-stranded beta-sandwich structure, capped by a C-terminal helix. The substrate peptide fits into an L-shaped surface cleft formed from the C-terminal helix and strands 5 and 6.[5]

Human proteins containing these domains

APBA1; APBA2; APBA3; EPS8; EPS8L1; EPS8L2; EPS8L3; TENC1; TNS; TNS1; TNS3; TNS4; DOK1; DOK2; DOK3; DOK4; DOK5; DOK6; DOK7; FRS2; FRS3; IRS1; IRS2; IRS4; TLN1; TLN2

References

  1. ^ McCleverty CJ, Lin DC, Liddington RC (June 2007). "Structure of the PTB domain of tensin1 and a model for its recruitment to fibrillar adhesions". Protein Sci. 16 (6): 1223–9. doi:10.1110/ps.072798707. PMC 2206669. PMID 17473008. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2206669. 
  2. ^ Chen H, Ishii A, Wong WK, Chen LB, Lo SH (October 2000). "Molecular characterization of human tensin". Biochem. J. 351 Pt 2: 403–11. PMC 1221376. PMID 11023826. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1221376. 
  3. ^ Lo SH (January 2004). "Tensin". Int. J. Biochem. Cell Biol. 36 (1): 31–4. doi:10.1016/S1357-2725(03)00171-7. PMID 14592531. 
  4. ^ Eck MJ, Dhe-Paganon S, Trub T, Nolte RT, Shoelson SE (May 1996). "Structure of the IRS-1 PTB domain bound to the juxtamembrane region of the insulin receptor". Cell 85 (5): 695-705. PMID 8646778. 
  5. ^ Zhou MM, Huang B, Olejniczak ET, Meadows RP, Shuker SB, Miyazaki M, Trub T, Shoelson SE, Fesik SW (April 1996). "Structural basis for IL-4 receptor phosphopeptide recognition by the IRS-1 PTB domain". Nat. Struct. Biol. 3 (4): 388-93. PMID 8599766. 

External Links

This article incorporates text from the public domain Pfam and InterPro IPR013625

This article incorporates text from the public domain Pfam and InterPro IPR002404