2LCT

Solution structure of the Vav1 SH2 domain complexed with a Syk-derived doubly phosphorylated peptide

Summary for 2LCT

• Entry DOI: 10.2210/pdb2lct/pdb
• NMR Information: BMRB: 17632
• Descriptor: Proto-oncogene vav, Tyrosine-protein kinase SYK (2 entities in total)
• Functional Keywords: phosphopeptide, syk kinase, tyrosine kinase, protein-peptide complex, phosphorylated peptide, phosphotyrosine binding domain, b cell signaling protein, signaling protein
• Biological source: Homo sapiens (human); More
• Cellular location: Cell membrane (Probable): P48025
• Total number of polymer chains: 2
• Total formula weight: 14009.60

Authors

Chen, C.,Gorenstein, N.,Post, C. (deposition date: 2011-05-09, release date: 2011-06-01, Last modification date: 2024-11-06)

Primary citation

Chen, C.H.,Martin, V.A.,Gorenstein, N.M.,Geahlen, R.L.,Post, C.B.
Two closely spaced tyrosines regulate NFAT signaling in B cells via Syk association with Vav.
Mol.Cell.Biol., 31:2984-2996, 2011

PubMed Abstract: Activated Syk, an essential tyrosine kinase in B cell signaling, interacts with Vav guanine nucleotide exchange factors and regulates Vav activity through tyrosine phosphorylation. The Vav SH2 domain binds Syk linker B by an unusual recognition of two closely spaced Syk tyrosines: Y342 and Y346. The binding affinity is highest when both Y342 and Y346 are phosphorylated. An investigation in B cells of the dependence of Vav phosphorylation and NFAT activation on phosphorylation of Y342 and Y346 finds that cellular response levels match the relative binding affinities of the Vav1 SH2 domain for singly and doubly phosphorylated linker B peptides. This key result suggests that the uncommon recognition determinant of these two closely spaced tyrosines is a limiting factor in signaling. Interestingly, differences in affinities for binding singly and doubly phosphorylated peptides are reflected in the on rate, not the off rate. Such a control mechanism would be highly effective for regulating binding among competing Syk binding partners. The nuclear magnetic resonance (NMR) structure of Vav1 SH2 in complex with a doubly phosphorylated linker B peptide reveals diverse conformations associated with the unusual SH2 recognition of two phosphotyrosines. NMR relaxation indicates compensatory changes in loop fluctuations upon binding, with implications for nonphosphotyrosine interactions of Vav1 SH2.

PubMed: 21606197
DOI: 10.1128/MCB.05043-11

Experimental method

SOLUTION NMR