| Source: |
Escherichia coli. |
| Molecular Weight: |
Approximately 21.8 kDa, a single non-glycosylated polypeptide chain containing 195 amino acids. |
| AA Sequence: |
MRPLAFSDAG PHVHYGWGDP IRLRHLYTSG PHGLSSCFLR IRADGVVDCA RGQSAHSLLE IKAVALRTVA IKGVHSVRYL CMGADGKMQG LLQYSEEDCA FEEEIRPDGY NVYRSEKHRL PVSLSSAKQR QLYKNRGFLP LSHFLPMLPM VPEEPEDLRG HLESDMFSSP LETDSMDPFG LVTGLEAVRS PSFEK |
| Purity: |
> 95% by SDS-PAGE and HPLC analyses. |
| Biological Activity: |
Assay #1: Fully biologically active when compared to standard. The biological activity is measured by its binding ability in a functional ELISA. Immobilized rHuFGF R4 at 5 μg/mL can bind rHuFGF-19 with a linear range of 3-200 ng/mL.Assay #2: Fully biologically active when compared to standard. The ED50 as determined by a cell proliferation assay using murine Balb/c 3T3 cells is less than 150 ng/mL, corresponding to a specific activity of > 6.7 × 103 IU/mg. |
| Physical Appearance: |
Sterile filtered white lyophilized (freeze-dried) powder. |
| Formulation: |
Lyophilized from a 0.2 µm filtered concentrated solution in PBS, pH7.4. |
| Endotoxin: |
Less than 1 EU/µg of rHuFGF-19 as determined by LAL method. |
| Reconstitution: |
Centrifuge the vial briefly before opening to ensure that the contents settle at the bottom. Reconstitute the vial with sterile distilled water or an aqueous buffer containing 0.1% BSA to achieve a concentration of 0.1-1.0 mg/mL. Divide the resulting stock solution into working aliquots and store them at or below -20°C. For further dilutions, use appropriate buffered solutions. |
| Stability & Storage: |
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
12 months from date of receipt, -20 to -70°C as supplied.
1 month, 2 to 8°C under sterile conditions after reconstitution.
3 months, -20 to -70°C under sterile conditions after reconstitution. |
| Background: |
The FGF-19 gene encodes for the Human FGF-19 protein, which is a part of the FGF-19 subfamily that includes FGF-19, 21, and 23. Traditionally, FGFs are seen as paracrine factors and are well-known for their roles in organogenesis and tissue organization during embryo development. However, recent studies show that the FGF-19 subfamily functions endocrinologically. Members of this subfamily have a limited capacity to bind to the heparin binding site, which is an essential factor in ligand-receptor complex formation. β-Klotho, identified as a necessary co-factor for FGF-19, 21, 23 signaling, significantly increases ligand-receptor affinity. FGF-19 is an exclusive ligand for FGF R4 unlike most FGFs which bind to and activate more than one FGF receptor. In FGF-19 transgenic mice, there are noticeable effects such as reduced liver triglycerides and glucose levels, increased fatty acid oxidation and improved insulin resistance. |
