SNX17/27/31 (IPR037831)

Short name: SNX17/27/31

Overlapping homologous superfamilies


Family relationships


SNX17/27/31 are known as PX-FERM proteins, a sub-group of the PX superfamily that contain a defining PtdInsP-binding PX domain, and a C-terminal 4.1, ezrin, radixin, moesin (FERM) domain with an atypical tertiary structure [PMID: 25472716]. They are modular peripheral membrane proteins that act as central scaffolds mediating protein-lipid interactions, cargo binding, and regulatory protein recruitment [PMID: 24359963].

SNX17 is a critical regulator of endosomal recycling of numerous receptors, channels, and other transmembrane proteins. It binds to Asn-Pro-Xaa-Tyr (NPxY) sequences in the cytoplasmic tails of cargo such as LDL receptors and the amyloid precursor protein [PMID: 21512128].

SNX27 is a core component of the SNX27-retromer, a multiprotein complex composed of SNX27, the WASH complex and the retromer complex. It specifically binds and directs sorting of a subset of transmembrane proteins containing a PDZ-binding motif at the C terminus [PMID: 20733053]. Its PDZ domain mediates binding to the retromer complex via direct interaction with VPS26 (VPS26A or VPS26B) [PMID: 23563491], while its PX domain mediates binding to phosphatidylinositol 3-phosphate (PtdIns(3P)) and localization to early endosome membranes [PMID: 20733053].

SNX31 is a sorting nexin that binds to PtdIns3P-enriched lipids via its N-terminal PX-domain. It also binds to uroplakins [PMID: 24914955].

GO terms

Biological Process

GO:0006886 intracellular protein transport

Molecular Function

GO:0035091 phosphatidylinositol binding

Cellular Component

No terms assigned in this category.

Contributing signatures

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