FGFb (fibroblast growth factor basic) or FGF2, belongs to the fibroblast growth factor (FGF) family, and interact with high-affinity transmembrane receptors to influence cell proliferation and tissue neovascularization. FGFb exists as five isoforms with distinct intracellular localizations and functions. The 18kDa isoform is predominantly cytosolic and acts through cell surface receptors, whereas the 22, 22.5, 24 and 34kDa isoforms are nuclear and may signal independent of transmembrane receptor pathways. In humans, the gene is located on the q arm of chromosome 4. Description: This SAFE™ (Serum and Animal Free, low Endotoxin) protein has been made in plants with no exposure to animal protein during expression or purification. This animal free product has very low levels of endotoxin. Fibroblast Growth Factor basic (FGF-b, also known as FGF-2) is a member of the FGF family, a highly conserved family of 16-34kDa heparin-binding proteins. FGF-b exists in several isoforms, and although they are equally active, only the 18kDa form is secreted while the 23kDa form localizes to the nucleus. It lacks the signal sequence peptide necessary for the ER/Golgi pathway, indicating that secretion occurs via an alternate pathway. FGF-b shares four common tyrosine kinase receptors, FGFR 1-4, and require the binding of a second surface protein, the ubiquitously expressed heparan sulfate proteoglycan, in order to fully activate these receptors. FGF family members affect the proliferation, differentiation, mobility, and survival of several cell types, including fibroblasts, osteoblasts, smooth muscle cells, and neuroblasts. FGF-b expression has been detected in several cell types, including fibroblasts, macrophages, endothelial cells, epithelial cells, and neurons. FGF-b is particularly important in embryonic development as triggers of neurogenesis, angiogenesis, and neovascularization and has most recently been studied for its ability to maintain the proliferation of embryonic stem cell cultures in an undifferentiated state. Some members of the family, including FGF-b, remain active during adulthood and play a role in bone formation and tissue repair. FGF family members are also implicated in many types of cancer and may contribute to tumor vascularization. Applications Reported: SAFE™ Human FGF basic Recombinant Animal Free Protein is biologically active. Applications Tested: The ED50 of this protein, as measured by proliferation assay of NIH3T3 mouse fibroblast cells, is less than or equal to 0.2ng/mL. This corresponds to a specific activity of greater than or equal to 5 x 10e6 Units/mg. Source: Plant expressed 146 amino acids (Pro143-Ser288) with 10 amino acid N terminal tag-accession NP_001997.5. Bioactivity: The ED50 of this protein, as measured by proliferation assay of NIH3T3 mouse fibroblast cells, is less than or equal to 0.2ng/mL. This corresponds to a specific activity of greater than or equal to 5 x 10e6 Units/mg. Endotoxin: Less than 0.005ng/ug (0.05 EU/ug) as measured by turbidity assay. Purity: Greater than or equal to 95% as determined by SDS-PAGE. Molecular Weight: 17.8 kDa. Storage: The lyophilized powder can be stored at less than or equal to -20°C. (Short term storage at 2-8°C). Reconstitute in sterile PBS to a concentration no less than 100 ug/mL. Once reconstituted, protein should be aliquoted and stored at -20°C or lower. For best stability add 0.1% BSA before freezing aliquots.