CRYSTAL STRUCTURE OF THE XLP PROTEIN SAP

File:1d1z.gif


1d1z, resolution 1.4Å

Drag the structure with the mouse to rotate

OverviewOverview

SAP, the product of the gene mutated in X-linked lymphoproliferative syndrome (XLP), consists of a single SH2 domain that has been shown to bind the cytoplasmic tail of the lymphocyte coreceptor SLAM. Here we describe structures that show that SAP binds phosphorylated and nonphosphorylated SLAM peptides in a similar mode, with the tyrosine or phosphotyrosine residue inserted into the phosphotyrosine-binding pocket. We find that specific interactions with residues N-terminal to the tyrosine, in addition to more characteristic C-terminal interactions, stabilize the complexes. A phosphopeptide library screen and analysis of mutations identified in XLP patients confirm that these extended interactions are required for SAP function. Further, we show that SAP and the similar protein EAT-2 recognize the sequence motif TIpYXX(V/I).

DiseaseDisease

Known diseases associated with this structure: Amyloidosis, secondary, susceptibility to OMIM:[104770], Lymphoproliferative syndrome, X-linked OMIM:[300490]

About this StructureAbout this Structure

1D1Z is a Single protein structure of sequence from Homo sapiens with as ligand. Full crystallographic information is available from OCA.

ReferenceReference

Crystal structures of the XLP protein SAP reveal a class of SH2 domains with extended, phosphotyrosine-independent sequence recognition., Poy F, Yaffe MB, Sayos J, Saxena K, Morra M, Sumegi J, Cantley LC, Terhorst C, Eck MJ, Mol Cell. 1999 Oct;4(4):555-61. PMID:10549287

Page seeded by OCA on Thu Feb 21 12:12:18 2008

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA