Recombinant Human papillomavirus type 16 Probable protein E5 (E5)

Acts to keep host cells in a proliferation-competent state upon differentiation. Enhances host epidermal growth factor receptor (EGFR) activation after stimulation by EGF by inhibiting EGFR internalization. Induces a redistribution of host caveolin-1 and glycosphingolipid (ganglioside GM1) components of lipid rafts to the plasma membrane. Since GM1s inhibit cytotoxic T-lymphocytes, block immune synapse formation, and enhance proliferative signaling by the EGFR, E5 may enhance immune evasion and cell proliferation via a common mechanism. E5 also alters endosomal pH by interacting with the vacuolar H+-ATPase, which is a proton pump responsible for acidifying cellular organelles. Additionally, E5 prevents transport of the major histocompatibility class I to the cell surface and retains the complex in the Golgi apparatus.

If the delivery form is liquid, the default storage buffer is Tris/PBS-based buffer, 5%-50% glycerol. If the delivery form is lyophilized powder, the buffer before lyophilization is Tris/PBS-based buffer, 6% Trehalose, pH 8.0.

We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Please reconstitute protein in deionized sterile water to a concentration of 0.1-1.0 mg/mL.We recommend to add 5-50% of glycerol (final concentration) and aliquot for long-term storage at -20°C/-80°C. Our default final concentration of glycerol is 50%. Customers could use it as reference.

"Endoplasmic reticulum-localized human papillomavirus type 16 E5 protein alters endosomal pH but not trans-Golgi pH." Disbrow G.L., Hanover J.A., Schlegel R. J. Virol. 79:5839-5846 (2005)

The shelf life is related to many factors, storage state, buffer ingredients, storage temperature and the stability of the protein itself. Generally, the shelf life of liquid form is 6 months at -20°C/-80°C. The shelf life of lyophilized form is 12 months at -20°C/-80°C.