Recombinant Human GDF-15 (CHO-expressed) Protein

Growth Differentiation Factor 15 (GDF-15), also called Macrophage inhibitory cytokine-1 (MIC-1), placental transforming growth factor-beta, prostate-derived factor, and placental bone morphogenetic protein, is a divergent member of the transforming growth factor beta(TGF-beta) superfamily. GDF-15 is highly expressed in placenta and is expressed at lower levels in kidney, pancreas, prostate and colon. It is also widely expressed in brain. Similarly to other TGF-beta family proteins, GDF-15 is synthesized as a large precursor protein that is cleaved at the dibasic cleavage site (RXXR) to release the carboxy-terminal domain. The carboxy-terminal domain of GDF-15 contains the characteristic seven conserved cysteine residues necessary for the formation of the cysteine knot and the single interchain disulfide bond. Furthermore, the carboxy-terminal domain contains two additional cysteine residues that form a fourth intrachain disulfide bond. Biologically active GDF-15 is a disulfide-linked homodimer of the carboxy-terminal 112 amino acid residues. Mature human GDF-15 shares 66.1% and 68.7% amino acid sequence similarity with rat and mouse GDF-15, respectively, which are remarkably low homologies between species in TGF-beta superfamily. GDF-15 has been shown to have various functions, including inhibition of production of tumor necrosis factor alpha (TNF-alpha) from lipopolysaccharide-stimulated macrophages, induction of cartilage formation, early‑stage endochonadal bone formation, and promotion of neuronal survival.