Glial Derived Neurotrophic Factor (GDNF) Recombinant, Human

GDNF is a disulfide-linked homodimeric neurotrophic factor structurally related to Artemin, Neurturin and Persephin. These proteins belong to the cysteine-knot superfamily of growth factors that assume stable dimeric protein structures. GDNF signals through a multicomponent receptor system, composed of a RET and one of the four GFRalpha (alpha1-alpha4) receptors. GDNF specifically promotes dopamine uptake and survival and morphological differentiation of midbrain neurons. Using Parkinson's disease mouse model, GDNF has been shown to improve conditions such as bradykinesia, rigidity, and postural instability. The functional human GDNF ligand is a disulfide-linked homodimer, of two 15kD polypeptide chains called monomers. Each monomer contains seven conserved cysteine residues, one of which (Cys101) is used for inter-chain disulfide bridging and the others are involved in intramolecular ring formation known as the cysteine knot configuration. Biological Activity: Assay#1: The ED50 as determined by the dose-dependent dopamine uptake by rat ventral mesencephalic cultures was found to be in the range of 5-10ng/ml. Assay #2: The ED50 was determioned by the proliferation of rat C6 cells is (same/less than)0.1ng/ml, cooresponding to a specific activity of (same/more than)1x10e7 units/mg. AA Sequence: MSPDKQMAVL PRRERNRQAA AANPENSRGK GRRGQRGKNR GCVLTAIHLN VTDLGLGYET KEELIFRYCS GSCDAAETTY DKILKNLSRN RRLVSDKVGQ ACCRPIAFDD DLSFLDDNLV YHILRKHSAK RCGCI Storage and Stability: Lyophilized powder may be stored at -20 degrees C. Stable for 12 months at -20 degrees C. Reconstitute with sterile ddH2O with a carrier protein. Aliquot and store at -20 degrees C. Reconstituted product is stable for 6 months at -20 degrees 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.