Phosphotyrosine-binding Domain - Ptb Domain

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. The PTB domain interacts with the cytoplasmic tails of beta integrin by binding to an NPXY motif.

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 residues on an 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. 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.

Human proteins containing these domains

Proteins with SH2 or PTB domains that interact with Receptor Tyrosine Kinases - Proteins with SH2 or PTB domains that interact with Receptor Tyrosine Kinases.

APBA1; APBA2; APBA3; APPL1; EPS8; EPS8L1; EPS8L2; EPS8L3; TENC1; TNS; TNS1; TNS3; TNS4; DOK1; DOK2; DOK3; DOK4; DOK5; DOK6; DOK7; FRS2; FRS3; IRS1; IRS2; IRS4; TLN1; TLN2

See also

Solution Structure of the Phosphotyrosine Binding (PTB) Domain of .... Source : www.researchgate.net

• SH2 domains also bind phosphorylated tyrosines

References

Review. Evolution of pTyr signalling | Philosophical Transactions .... Source : rstb.royalsocietypublishing.org

External links

High-Affinity Binding of the Drosophila Numb Phosphotyrosine .... Source : www.researchgate.net

• Eukaryotic Linear Motif resource motif class LIG_PTB_Phospho_1

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

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

Phosphotyrosine Binding Domain - Semantic Scholar. Source : www.semanticscholar.org