SNX9
Description
The SNX9 (sorting nexin 9) is a protein-coding gene located on chromosome 6.
Sorting nexin-9 is a protein that in humans is encoded by the SNX9 gene. 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 does not contain a coiled coil region, like some family members, but does contain an SH3 domain near its N-terminus. This protein interacts with the cytoplasmic domains of the precursor but not the processed forms of a disintegrin and metalloprotease domain 9 and 15. This protein binds the beta-appendage domain of adaptor protein 2 and may function to assist adaptor protein 2 in its role at the plasma membrane. This protein interacts with activated Cdc42-associated kinase-2 to regulate the degradation of epidermal growth factor receptor protein.
== Interactions == SNX9 has been shown to interact with ADAM9, DNM2 and ADAM15.
SNX9 is involved in both endocytosis and intracellular vesicle trafficking, playing a role during interphase and at the end of mitosis. It is crucial for efficient progression through mitosis and cytokinesis, and for the proper formation of the cleavage furrow at the end of mitosis. SNX9 participates in endocytosis through clathrin-coated pits, as well as clathrin-independent, actin-dependent fluid-phase endocytosis. It also plays a role in macropinocytosis. SNX9 promotes the internalization of TNFR and the degradation of EGFR after EGF signaling. It stimulates the GTPase activity of DNM1 and promotes its oligomerization. Furthermore, SNX9 activates the Arp2/3 complex through WASL, contributing to the reorganization of the F-actin cytoskeleton. SNX9 binds to membranes enriched in phosphatidylinositol 4,5-bisphosphate, promoting membrane tubulation. It has a lower affinity for membranes enriched in phosphatidylinositol 3-phosphate.
SNX9 is also known as SDP1, SH3PX1, SH3PXD3A, WISP.
