Recombinant Human CG alpha / CGA Protein, His Tag, 100 µg

Background
Chorionic gonadotrophin subunit alpha (CGA),a member of the glycoprotein hormones subunit alpha family, is also known as glycoprotein hormones alpha chain, choriogonadotropin alpha chain, follicle-stimulating hormone alpha chain (FSH-alpha), luteinizing hormone alpha chain (LSH-alpha) and thyroid-stimulating hormone alpha chain (TSH-alpha). The hormones human chorionic gonadotropin (hCG), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and thyroid-stimulating hormone (TSH) are dimers consisting of alpha and beta subunits that are associated noncovalently. The alpha subunits (CGA) of these four human glycoprotein hormones are nearly identical, however, their beta chains are unique and confer biological specificity.

Source
Recombinant Human CGA /TSH alpha Protein,HEK293 expressed (rh CGA / TSH alpha) Ala 25 - Ser 116 (Accession # AAH20782) was produced in human 293 cells (HEK293)

Molecular Characterization
rh CGA / TSH alpha is fused with a polyhistidine tag at the C-terminus, and has a calculated MW of 12.1 kDa. The predicted N-terminus is Ala 25. DTT-reduced Protein migrates as 22-26 kDa in SDS-PAGE due to glycosylation.

Endotoxin
Less than 1.0 EU per μg of the rh CGA / TSH alpha by the LAL method.

Purity
>92% as determined by SDS-PAGE.

Formulation
Lyophilized from 0.22 μm filtered solution in PBS, pH 7.4. Normally Mannitol or Trehalose are added as protectants before lyophilization.

Reconstitution
See Certificate of Analysis for reconstitution instructions and specific concentrations.

Storage
Avoid repeated freeze-thaw cycles.
No activity loss was observed after storage at:
In lyophilized state for 1 year (4°C); After reconstitution under sterile conditions for 3 months (-70°C).

References

(1) Sairam M.R., et al., 1977, Can. J. Biochem. 55:755-760.
(2) Rathnam P., et al., 1975, J. Biol. Chem. 250:6735-6746.
(3) Fan Q.R., et al., 2005, Nature 433:269-277.