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The PX domain: a new phosphoinositide-binding module.

Chris D Ellson·Simon Andrews·Len R Stephens·Phill T Hawkins
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Abstract

The PX domain, which until recently was an orphan domain, has emerged as the latest member of the phosphoinositide-binding module superfamily. Structural studies have revealed that it has a novel fold and identified key residues that interact with the bound phosphoinositide, enabling some prediction of phosphoinositide-binding specificity. Specificity for PtdIns(3)P appears to be the most common, and several proteins containing PX domains localise to PtdIns(3)P-rich endosomal and vacuolar structures through their PX domains: these include the yeast t-SNARE Vam7p, mammalian sorting nexins (involved in membrane trafficking events) and the Ser/Thr kinase CISK, which is implicated in cell survival. Additionally, phosphoinositide binding to the PX domains of p40(phox) and p47(phox) appears to play a critical role in the active assembly of the neutrophil oxidase complex.

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Binding SitesCarrier ProteinsEndosomesEye ProteinsFatty Acid-Binding ProteinsModels, MolecularPhagosomesPhosphatidylinositol PhosphatesPhosphatidylinositolsProtein Structure, TertiaryVacuolessrc Homology DomainsJournal ArticleReview

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BibTeXRIS

Chris D Ellson, Simon Andrews, Len R Stephens, Phill T Hawkins. 2002-03-15. The PX domain: a new phosphoinositide-binding module.. https://doi.org/10.1242/jcs.115.6.1099

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