SNX9 (F9G1M) Rabbit mAb #54984

Sorting nexins (SNXs) are a family of cytoplasmic proteins characterized by the presence of a phosphatidylinositol 3-phosphate (PI3P) binding phox (PX) domain. This binding occurs mainly in the early endosome and allows for trafficking of the bound protein to either a degradative or recycling pathway (1). Sorting nexin family member 9 (SNX9) is a multifunctional scaffolding protein that plays an important role in clathrin-mediated endocytosis (CME) (2). In CME, SNX9 binds to the protein clathrin at the plasma membrane and recruits the GTPase dynamin to facilitate membrane fission and vesicle release (3). SNX9 also recruits the protein N-WASP to the cell membrane, a key regulator of actin dynamics (4). SNX9’s function in actin assembly contributes to cancer progression, primarily by affecting cell invasion and metastasis. For instance, SNX9 has been shown to promote metastasis in breast cancer through its interaction with N-WASP and RhoA-ROCK (5). Interestingly, SNX9 has also been shown to have reduced expression in primary tumors relative to healthy tissue (6). In this context, SNX9 downregulation promotes the formation of actin-rich structures known as invadopodia, which are required for cancer cells to invade through the basement membrane (6). SNX9 is also recruited to immunological synapses during T cell activation, where it complexes with N-WASP, p85, and CD28 to internalize CD28 via CME (7,8). Furthermore, targeted knockout of SNX9 has been shown to alleviate CD8+ T cell exhaustion, suggesting its use as a therapeutic target in cancer immunotherapies (9).