Sorting Nexin 1, PX domain (IPR034901)

Short name: PX_SNX1

Overlapping homologous superfamilies

Domain relationships


The Phox Homology (PX) domain is a phosphoinositide (PI) binding module present in many proteins with diverse functions. Sorting nexins (SNXs) make up the largest group among PX domain containing proteins. They are involved in regulating membrane traffic and protein sorting in the endosomal system. The PX domain of SNXs binds phosphoinositides (PIs) and targets the protein to PI-enriched membranes [PMID: 16782399, PMID: 11439176]. SNXs differ from each other in PI-binding specificity and affinity, and the presence of other protein-protein interaction domains, which help determine subcellular localization and specific function in the endocytic pathway [PMID: 15634208, PMID: 16243015, PMID: 12461558].

SNX1 harbors a Bin/Amphiphysin/Rvs (BAR) domain, which detects membrane curvature, C-terminal to the PX domain. Both domains have been shown to determine the specific membrane-targeting of SNX1 [PMID: 15498486]. SNX1 is components of the retromer complex, a membrane coat multimeric complex required for endosomal retrieval of lysosomal hydrolase receptors to the Golgi [PMID: 19081543]. The retromer consists of a cargo-recognition subcomplex and a subcomplex formed by a dimer of sorting nexins (SNX1 and/or SNX2), which ensures efficient cargo sorting by facilitating proper membrane localization of the cargo-recognition subcomplex [PMID: 17101778].

This entry represents the SNX1 PX domain.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.