Introduction
Growth differentiation factor 5 (GDF-5), a member of the transforming growth factor beta (TGF-β) superfamily, plays a crucial role in bone and cartilage development. GDF-5 is synthesized as a precursor protein that undergoes proteolytic cleavage to release its active form, which forms homodimers. These homodimers bind to cell surface receptors, initiating signaling pathways that regulate cell proliferation, differentiation, and extracellular matrix production, essential processes for skeletal morphogenesis. Mutations in the GDF-5 gene have been linked to skeletal dysplasias, highlighting its importance in human skeletal health.
Description
Recombinant Mouse GDF5, expressed in E. coli, is a non-glycosylated homodimeric protein. Each subunit, composed of 120 amino acids, contributes to a total molecular weight of 27.2 kDa. The protein is purified using proprietary chromatographic techniques, ensuring high purity for research applications.
Physical Appearance
The product appears as a sterile, white powder obtained through lyophilization (freeze-drying).
Formulation
The GDF-5 protein was subjected to lyophilization from a 0.2µm filtered solution containing 30% Acetonitrile and 0.1% TFA at a concentrated state.
Solubility
To reconstitute the lyophilized GDF5, it is recommended to dissolve it in sterile 4mM HCl at a concentration not less than 100µg/ml. This solution can then be further diluted into other desired aqueous solutions.
Stability
Lyophilized GDF5 remains stable at room temperature for a period of 3 weeks. However, for long-term storage, it is recommended to store it desiccated at a temperature below -18°C. Once reconstituted, the GDF-5 solution should be stored at 4°C for a maximum of 2-7 days. For extended storage, freezing at -18°C is advisable. It is crucial to avoid repeated freeze-thaw cycles to maintain protein stability. The addition of a carrier protein (0.1% HSA or BSA) is recommended for long-term storage.
Purity
The purity of GDF5 exceeds 96.0%, as determined by two methods: (a) Reverse-Phase High-Performance Liquid Chromatography (RP-HPLC) analysis and (b) Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) analysis.
Biological Activity
The biological activity of GDF5 is measured through its ability to induce alkaline phosphatase production in murine ATDC5 cells. The ED50, which represents the concentration required for half-maximal response, is determined to be less than 1.0µg/ml. This corresponds to a specific activity greater than 1000IU/mg, indicating high potency.
Synonyms
Bmp-14, Bp, GDF-5, Bone morphogenetic protein 14, GDF5, Growth/differentiation factor 5.
Amino Acid Sequence
APLANRQGKR PSKNLKARCS RKALHVNFKD MGWDDWIIAP LEYEAFHCEG LCEFPLRSHL EPTNHAVIQT LMNSMDPEST PPTCCVPTRL SPISILFIDS ANNVVYKQYE DMVVESCGCR.
