Growth differentiation factor 15 (GDF-15) is a distant member of the TGFβ superfamily. Its expression is tightly regulated and circulating GDF15 protein in serum is associated with diseases such as cancer, cardiovascular disease, obesity and metabolic disease. GDF15 protein is being recognized an important biomarker for cellular stress.

Unlike other members of the TGFβ superfamily that cause activation of the SMAD pathway, GDF15 protein signals through GRAL and co-receptor RET leading to RET phosphorylation and signalling through the ERK and AKT pathway (reviewed in Emmerson et al., 2018). Commercial sources of recombinant human GDF15 protein, in particular those purified from mammalian expression are frequently contaminated with trace amounts of TGFβ and related proteins. These trace contaminants cause misleading experimental results due to the picomolar or even femtomolar EC50s of this family of cytokines (2).  Please be cautious with your source of recombinant GDF15 protein, our scientists are happy to provide further information, please email support@qkine.com

We produce our proteins in E. coli with no animal products in our culture or purification processes to ensure there is no contamination from related proteins. In addition, we use a well-characterized SMAD2/3 activation assay to confirm there is no SMAD signalling.

Summary: Qk015 Mature domain of human GDF15 protein (Uniprot: Q99988) expressed in E. coli and purified to homogeneity. Mature active protein is a disulfide-linked dimer.

Molecular mass: ~25 kDa (for the dimer)

Form: protein is provided lyophilized from a fully volatile solution without carrier protein.