|PROSITE documentation PDOC51064|
Proteins encoding phosphotyrosine binding (PTB) domains function as adaptors or scaffolds to organize the signaling complexes involved in wide-ranging physiological processes including neural development, immunity, tissue homeostasis and cell growth. Due to structural differences, PTB domains are divided into three groups represented by phosphotyrosine-dependent IRS-like, phosphotyrosine-dependent Shc-like (see <PDOC00907>), and phosphotyrosine-independent Dab-like PTBs (see <PDOC00907>).
IRS-type PTB domain has an average length of about 100 amino acids. It binds to the insulin receptor through the Asn-Pro-Xaa-Tyr(P) motif found in many tyrosine-phosphorylated proteins. This domain is found in IRS/Dok/SNT proteins that are the major adapters for RTK and cytokine signaling. This domain binds both peptides and headgroups of phosphatidylinositides, utilizing two distinct binding motifs to mediate spatial organization and localization within cells. The IRS-type PTB domain is found alone or in association with the PH domain (see <PDOC50003>) [1,2].
The 3D structure of IRS-type PTB domain has been solved (see <PDB:1P5T>) . It shares a folding pattern commonly referred to as the PH-domain "superfold". The core "superfold" consists of seven antiparallel β strands forming two orthogonal β sheets. This β sandwich is capped at the C terminus by an α helix. It contains a peptide binding pocket (formed by the β strand 5 and the C-terminal α helix) and a highly basic phospholipid binding "crown" (largely composed of residues from loop regions near the N terminus) .
IRS-type PTB domain has also been found in the proteins listed below.
The profile we developed covers the entire IRS-type PTB domain.Note:
Talin proteins may contain an IRS-type PTB domain. This family is however too divergent to be detected by this profile.Last update:
January 2005 / First entry.
PROSITE method (with tools and information) covered by this documentation:
|1||Authors||Uhlik M.T. Temple B. Bencharit S. Kimple A.J. Siderovski D.P. Johnson G.L.|
|Title||Structural and evolutionary division of phosphotyrosine binding (PTB) domains.|
|Source||J. Mol. Biol. 345:1-20(2005).|
|2||Authors||Eck M.J. Dhe-Paganon S. Trub T. Nolte R.T. Shoelson S.E.|
|Title||Structure of the IRS-1 PTB domain bound to the juxtamembrane region of the insulin receptor.|
|3||Authors||Shi N. Ye S. Bartlam M. Yang M. Wu J. Liu Y. Sun F. Han X. Peng X. Qiang B. Yuan J. Rao Z.|
|Title||Structural basis for the specific recognition of RET by the Dok1 phosphotyrosine binding domain.|
|Source||J. Biol. Chem. 279:4962-4969(2004).|