Recombinant human activin E PLUS™ (Avi-tag) protein (Qk082)

Activin E is not traditionally classified as a cytokine. Instead, it is part of the transforming growth factor-beta (TGF-β) superfamily. While it has signaling functions similar to cytokines, it is more accurately described as a growth factor within the TGF-β family.

Activin E primarily binds to the activin receptor-like kinase 7 (ALK7), also known as ACVR1C. This receptor is part of the TGF-β signaling pathway and is expressed in various tissues, including adipose tissue. When Activin E binds to ALK7, it initiates signaling cascades that influence metabolic processes, such as the regulation of adipose tissue function and energy homeostasis. This interaction is particularly important in controlling lipid metabolism and insulin sensitivity.

The Activin E gene, known as INHBE, encodes for the Activin E protein.

Activin E is a protein belonging to the TGF-beta superfamily, involved in the regulation of inflammation, metabolism and muscle growth.

The Activin E pathway is part of the larger TGF-β signaling pathway and involves the binding of Activin E to its receptor, primarily ALK7 (activin receptor-like kinase 7). Upon binding, ALK7 undergoes phosphorylation, which activates intracellular signaling cascades, particularly the SMAD proteins. These SMAD proteins then translocate to the nucleus, where they regulate the expression of target genes involved in metabolic processes such as lipid metabolism, adipose tissue function, and energy homeostasis.

Activin E is primarily expressed in the liver and has been implicated in metabolic processes, including the regulation of glucose and lipid metabolism. Additionally, Activin E has been detected in adipose tissue and the gastrointestinal tract. 

An Avi-tag is a short, artificial peptide sequence that acts as a substrate for the biotin ligase enzyme, BirA, leading to the highly efficient and site-specific addition of biotin. This biotinylated protein can then be easily detected, purified, or immobilized using streptavidin or avidin, which bind tightly to biotin. Avi-tags are useful tools in molecular biology and biotechnology.

TGF beta family proteins and other growth factors can be very poorly soluble in physiological solutions.  Please follow the handling guidance for lyophilized cytokines below to minimize loss of protein due to precipitation or adsorption to plastic.  We advise storing the recombinant protein at very low pH before dilution in cell culture media or final working solutions. Low pH will also assist in maintaining the correct disulfide structure of the protein by minimizing disulfide bond exchange reactions.

• Resuspension in physiological buffers may cause precipitation of stock solutions, hence we recommend dissolving our lyophilized cytokines in 10 mM HCl (1:1000 dilution of concentrated HCl) while keeping the protein concentration at 50 µg/ml or above, in order to avoid loss by adsorption to plasticware.
• To ensure you recover all of the protein, let the sample sit for a few minutes with the solubilization buffer at room temperature and pipette gently up and down (avoid foaming).
• Rinse the tube with some more 10 mM HCl and pool with the rest.
• The protein is tolerant of some freeze and thaw cycles, but as always with proteins, it is better to aliquot and store frozen.
• Our proteins are supplied carrier-protein free.  If compatible with your work, add carrier protein of your choice such as BSA, HSA or gelatin to further minimize loss by adsorption.
• Store in -80°C for long term storage. -20°C for short-term.

Every effort is made to ensure samples are sterile; however, we recommend sterile filtering after dilution in media or the final working solution.