Hu Recom Myostatin, 100 µg

STEMCELL Technologies offers Human Recombinant Myostatin, a member of the transforming growth factor beta (TGF-β) superfamily. The protein signals by binding to the activin type II receptor, recruiting either the ALK3 or ALK4 coreceptor, and activating SMAD2/3. Released by myocytes, it inhibits muscle growth and regenerative capacity, and it influences lipid catabolic metabolism in adipocytes while inhibiting preadipocyte differentiation, as demonstrated in the 3T3-L1 cell line.

Also referred to as GDF-8 (Growth differentiation factor 8) and MSTN, the protein (accession number O14793) has a predicted molecular mass of 12.4 kDa as a monomer and 24.8 kDa as a dimer, and shows cross-reactivity with mouse and rat. It is expressed in E. coli and purified to ≥ 95%, supplied as a lyophilized powder prepared from a sterile filtered aqueous solution containing 0.1% trifluoroacetic acid. Endotoxin levels are ≤ 1.0 EU/μg protein as measured by kinetic Limulus amebocyte lysate (LAL) analysis.

Specific activity is ≥ 2.0 x 10^4 units/mg, corresponding to an EC50 ≤ 50 ng/mL, as determined by a cytotoxicity assay using MPC-11 cells, with cell viability measured after 66 hours using a fluorometric assay method (an example assay produced an EC50 of 12 ng/mL). The lyophilized product is stable at -20°C to -80°C for 12 months from the date of receipt. For reconstitution, the vial should be centrifuged first and the contents resuspended in 20 mM hydrochloric acid containing 0.1% bovine serum albumin (BSA) to at least 0.1 mg/mL without vortexing; reconstituted material can be stored at 2 - 8°C for up to 1 month or at -20°C to -80°C for up to 3 months. Repeated freeze-thaw cycles should be avoided.