This gene encodes a member of the sorting nexin family. Members of this family contain a phox (PX) domain, which is a phosphoinositide binding domain, and are involved in intracellular trafficking. This protein associates with the long isoform of the leptin receptor, the transforming growth factor-beta family of receptor serine-threonine kinases, and with receptor tyrosine kinases for platelet-derived growth factor, insulin, and epidermal growth factor. This protein may form oligomeric complexes with family member proteins through interactions of both the PX domain and the coiled coil regions of the molecules. Translocation of this protein from the cytoplasm to the nucleus occurs after binding to proviral integration site 1 protein. This gene results in two transcripts encoding two distinct isoforms. [provided by RefSeq, Jul 2008].
Function: May be involved in several stages of intracellular trafficking. Promotes lysosomal degradation of CDKN1B (By similarity). Plays a role in retrograde protein transport from endosomes to the trans-Golgi network. May function as link between transport vesicles and dynactin. Negatively regulates retrograde transport of BACE1 from the cell surface to the trans-Golgi network. May contribute to transcription regulation.