| Source: |
Escherichia coli |
| Molecular Weight: |
Approximately 6 kDa, a single non-glycosylated polypeptide chain containing 50 amino acids. |
| AA Sequence: |
MVVSHFNDCPDSHTQFCFHGTCRFLVQEDKPACVCHSGYVGARCEHADLLA |
| Purity: |
>95% by SDS-PAGE analyses. |
| Physical Appearance: |
Sterile filtered white lyophilized (freeze-dried) powder. |
| Formulation: |
Lyophilized from a 0.2 μm filtered solution in PBS, with 0.02% Tween-20, pH7.0. |
| Endotoxin: |
Less than 0.1 EU/µg of rHuTGF-α as determined by LAL method. |
| Reconstitution: |
Prior to opening, it is recommended to centrifuge the vial briefly to bring the contents down the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1% BSA to a concentration of 0.1-1.0 mg/mL. If animal-origin-free condition is expected in your product, then sterile distilled water is recommended. Stock solutions should be apportioned into working aliquots and stored at ≤ -20°C. Further dilutions should be made in appropriate buffered solutions. Do not reconstitute in cell culture media directly. |
| Stability & Storage: |
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
A minimum of 12 months from date of receipt, when stored at ≤ -20°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: |
TGF-alpha was first discovered in the conditioned media of cells that had undergone oncogenic transformation, exhibiting bioactivity akin to that of EGF. Belonging to the EGF family of cytokines, TGF-alpha is initially synthesized as transmembrane precursors, featuring one or more EGF structural units within their extracellular domain. These cytokines are liberated from the transmembrane protein through proteolytic cleavage, transitioning into soluble forms. Interestingly, the membrane-bound proTGF-alpha retains biological activity and appears to facilitate cell-cell adhesion while stimulating neighboring cells in a juxtacrine manner.
TGF-alpha expression is widespread in tumors and transformed cells, but it's also present in normal tissues during embryonic development and in various adult tissues such as the pituitary, brain, keratinocytes, and macrophages. Its mature form shares a strikingly high amino acid sequence identity of about 93% with mouse or rat TGF-alpha, and it exhibits biological effects across species.
Upon binding to the EGF receptor, TGF-alpha triggers the activation of receptor tyrosine kinase. Consequently, it demonstrates comparable potency to EGF in stimulating fibroblast proliferation and inducing epithelial development in vivo. Moreover, TGF-alpha reportedly surpasses EGF in its angiogenic effects and in promoting keratinocyte migration. Notably, the EGF receptor gene serves as the cellular counterpart of the avian v-erb-B oncogene. |
