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| Alternative Name : |
Somatomedin C, IGF-I, IGFI. |
| Amount : |
50 µg |
Source : Escherichia Coli. Insulin-Like Growth Factor-IGilthead SeabreamRecombinant produced in E.Coli is a single, non-glycosylated, polypeptide chain containing 68 amino acids and having a molecular mass of 7545.4 Dalton, the predicted pI=7.72.IGF-1 is purified by proprietary chromatographic techniques. The somatomedins, or insulin-like growth factors (IGFs), comprise a family of peptides that play important roles in mammalian growth and development. IGF1 mediates many of the growth-promoting effects of growth hormone (GH; MIM 139250). Early studies showed that growth hormone did not directly stimulate the incorporation of sulfate into cartilage, but rather acted through a serum factor, termed 'sulfation factor,' which later became known as 'somatomedin' (Daughaday et al., 1972). Three main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2; MIM 147470), and somatomedin B (MIM 193190) (Rotwein, 1986; Rosenfeld, 2003).
It is recommended to reconstitute the lyophilized IGF-1 in sterile 0.4% NaHCO3 adjusted, not less than 100µg/ml, which can then be further diluted to other aqueous solutions. Binding assays of the 125I-Gealthead Seabream IGF1 to Gilthead Seabream or carp (Cyprinus carpio) sera resulted in high specific binding, indicating the existence of one or more IGF-binding proteins. In binding experiments to crude Gilthead Seabream brain homogenate, using human (h) IGF-I as a ligand, the respective IC50 value of hIGF1 was about fourfold lower than that of Gilthead Seabream IGF-1. Recombinant Gilthead Seabream IGF-1 exhibited mitogenic activity in a mouse mammary gland-derived MME-L1 cell line which was approximately 200-fold lower than that of hIGF1. Binding experiments to intact MME-L1 cells suggests that this difference most likely results from a correspondingly lower affinity for IGF1 receptor in these cells. In contrast, the activities of Gilthead Seabream IGF-I and hIGF-I measured by 35S uptake by gill arches from the goldfish (Carassius auratus) were identical, indicating that the recombinant Gilthead Seabream IGF-I is biologically active.
