SCGN Protein, Human (His)

Secretagogin (SCGN) is a biomarker of neuroendocrine cells, and a gene product of the SCGN gene located on chromosome 6p22.3-p22.1. SCGN is a calcium binding protein that is highly expressed in neuroendocrine cells, and six EF-hand calcium-binding proteins are postulated to be involved in transmitting calcium signals to control cell proliferation. SCGN enhances pancreatic insulin secretion, and is a useful biomarker for endocrine tumors, stroke, and psychiatric conditions. SCGN also exerts a neuroprotective role in neurodegenerative diseases, such as Alzheimer's disease. In addition, RIN-5F insulinoma cell clones exhibit retarded cell growth following overexpression of SCGN, suggesting their involvement in growth control and differentiation or inhibition of cell replication by Ca²⁺ signal modulation^[1].
extracellular SCGN is readily internalized into the C2C12 cells in an energy-dependent manner. SCGN internalizes via clathrin-mediated endocytosis, following which, SCGN localizes largely in the cytosol. Exogenous SCGN treatment induces a global proteomic reprogramming in C2C12 cells^[2].
SCGN is expressed largely in pancreatic β-cells, certain parts of the brain, and also in neuroendocrine tissues. The expression of SCGN is altered in several diseases, such as diabetes, cancers, and neurodegenerative disorders. In the presence of Ca²⁺, SCGN efficiently prevents the aggregation of a broad range of model proteins in vitro. Ca²⁺ induces the conversion of a closed compact apo-SCGN conformation into an open extended holo-SCGN conformation via multistate intermediates, consistent with the augmentation of chaperone activity of SCGN^[3].