Ephrin-A1, also known as B61 and LERK-1, is a member of the Ephrin-A family of GPI-anchored ligands that bind and induce the tyrosine autophosphorylation of Eph receptors. Ephrin-A ligands are structurally related to the extracellular domains of the transmembrane Ephrin-B ligands. Eph-Ephrin interactions are widely involved in the regulation of cell migration, tissue morphogenesis, and cancer progression. Human Ephrin-A1 is synthesized with an 18aa signal peptide, a 164aa mature chain, and a 23aa C-terminal propeptide which is removed prior to GPI linkage of Ephrin-A1 to the membrane. It can also be released as a soluble molecule. The mature 21-25kD human Ephrin-A1 shares 85% aa sequence identity with mouse and rat Ephrin-A1. Alternate splicing generates an additional isoform that lacks 22aa in the juxtamembrane region. This short isoform is also expressed on the cell surface and exhibits weakened binding to EphA2. Ephrin-A1 is widely expressed on endothelial and epithelial cells, particularly in the lung, intestine, liver, and skin. It is expressed on resting CD4+ T cells but is down-regulated following activation. Ligation of Ephrin-A1 on CD4+ T cells inhibits cell proliferation and activation, although soluble Ephrin-A1 can promote T cell chemotaxis. In cancer, Ephrin-A1 is expressed by tumor cells as well as on the tumor-associated vasculature. It inhibits tumor cell proliferation and migration but also supports tumor growth by promoting angiogenesis. Soluble Ephrin-A1 additionally promotes neuronal survival and neurite extension.
Source:Recombinant corresponding to aa1-182 from human Ephrin-A1 Fc Chimera expressed in mouse myeloma cell line, NS0.
Molecular Weight:~46kD
Biological Activity:Measured by its binding ability in a functional ELISA. When Recombinant Human (rh) EphA2 is coated at 2ug/ml (100ul/well), the concentration of rhEphrin-A1 Fc Chimera that produces 50% of the optimal binding response is found to be ~0.6-3ng/ml.
Endotoxin: ~1EU/1ug (LAL)
Storage and Stability:Lyophilized powder may be stored at -20°C. Stable for 12 months at -20°C. Reconstitute with sterile buffer. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Reconstituted product is stable for 3 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
仕様
Size：50ug
Source Antigen：Recombinant, NSO cells
Grade：Highly Purified
Purity：~95% (SDS-PAGE)
Form：Supplied as a lyophilized powder in PBS. BSA free. Reconstitute with PBS to 0.1mg/ml.
