Synonym(s): IGF-I
Purity: >97% (SDS-PAGE)
Physical form: Lyophilized from a 0.2 μm filtered solution in phosphate buffered saline.
Analysis Note: The biological activty is measured in a serum-free cell proliferation assay using the human breast carcinoma cell line, MCF-7.
Storage: −20°C
Biochem/physiol Actions: IGF-1 belongs to the insulin-like growth factor (IGF; see MIM 147440) family of signaling molecules that play critical roles in cellular energy metabolism and in growth and development, especially prenatal growth.
IGF-I also known as somatomedin C, is secreted from the liver into circulation in a process regulated by pituitary growth hormone (GH) and so it mediates the growth-promoting activity of GH. In the developing embryo IGF-I is expressed primarily by mesenchymal-derived cells. After birth IGF-I expression in most extrahepatic tissues declines and hepatic expression of IGF-I becomes GH-regulated. Expression of IGF-I outside the liver is regulated differently, depending on the specific tissues. For example, gonadotropins and sex steroids regulate IGF-I expression within the reproductive system, while parathyroid hormone and sex steroids regulate IGF-I expression in bone. IGF-I is produced in several human tumors. IGF-I is mitogenic for a variety of cells including fibroblasts, osteoblasts, smooth muscle cells, fetal brain cells, neuroglial cells, and erythroid progenitor cells. IGF-I exerts its actions exclusively through the IGF-I receptor (IGF-IR). IGF-I induces endothelial cell migration and is involved in the regulation of angiogenesis.
Empirical Formula (Hill Notation): C3H9N