2g35 | pdb_00002g35
NMR structure of talin-PTB in complex with PIPKI
Structural highlights
Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedPhosphatidylinositol-4,5-bisphosphate (PIP2) is a key lipid messenger that regulates myriad diverse cellular signaling pathways. To ensure specificity in disparate cellular events, PIP2 must be localized to specific sub-cellular sites. At PIP2-regulated focal adhesion (FA) sites, such localization is in part mediated via the recruitment and activation of PIP2-producing enzyme, type Igamma phosphatidylinositol phosphate kinase (PIPKIgamma), by a phosphotyrosine binding (PTB) domain of talin. Transient phosphorylation of PIPKIgamma at Y644 regulates the interaction and efficient FA targeting of PIPKIgamma; however, the underlying structural basis remains elusive. We have determined the NMR structure of talin-1 PTB in complex with the Y644-phosphorylated PIPKIgamma fragment (WVpYSPLH). As compared to canonical PTB domains that typically recognize the NPXpY turn motif from a variety of signaling proteins, our structure displays an unusual non-NPXpY-based recognition mode for talin-1 PTB where K(357)RW in beta5 strand forms an antiparallel beta-sheet with the VpYS of PIPKIgamma. A specific electrostatic triad between K357/R358 of talin-1 PTB and the pY644 of PIPKIgamma was observed, which is consistent with the mutagenesis and isothermal calorimetry data. Combined with previous in vivo data, our results provide a framework for understanding how phosphorylation of Y644 in PIPKIgamma promotes its specific interaction with talin-1, leading to efficient local synthesis of PIP2 and dynamic regulation of integrin-mediated FA assembly. Structural basis for the phosphorylation-regulated focal adhesion targeting of type Igamma phosphatidylinositol phosphate kinase (PIPKIgamma) by talin.,Kong X, Wang X, Misra S, Qin J J Mol Biol. 2006 May 26;359(1):47-54. Epub 2006 Mar 23. PMID:16616931[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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