Recombinant Human ZAG Protein, CF

Recombinant Human ZAG Protein, CF Summary

Product Specifications

Product Datasheets

Carrier Free

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: ZAG

ZAG (zinc‑ alpha ₂‑glycoprotein; also called AZGP1) is a 40 ‑ 43 kDa secreted member of the MHC class I family of proteins (1 ‑ 5). It was previously called LMF in humans to reflect its activity as a lipid mobilizing factor that is upregulated in plasma and urine of cancer patients with cachexia (4, 6). Human ZAG cDNA encodes a 20 amino acid (aa) signal sequence and a 278 aa mature protein that contains one MHC class I antigen region and a C1‑type Ig‑like domain. The region equivalent to the MHC peptide groove is hydrophobic and likely binds lipid molecules rather than peptides (1, 3). An RGD sequence (aa 251 ‑ 253) that occurs in human but not mouse mediates integrin adhesion (1). ZAG is reported to associate with PIP (prolactin‑inducible protein) but not the MHC light chain, beta 2‑microglobulin (3, 7). Mature human ZAG shares 57 ‑ 66% aa sequence identity with mouse, rat, canine and equine ZAG. Human ZAG is active in mice (6, 8).  It is produced by secretory epithelia and is present in most body fluids (9). It is abundantly produced by adipocytes and is classed as an adipokine that stimulates adiponectin secretion (4, 10, 11). Its expression is downregulated by macrophage‑associated inflammation in adipose tissue, and it is underexpressed in obesity and diabetes (8, 10 ‑ 12). Serum ZAG is produced by liver epithelia, while prostate epithelia produce seminal fluid ZAG that can bind sperm and initiate motility (1, 12). ZAG stimulates lipid breakdown, at least in part by inducing expression of the uncoupling proteins UCP1 and UCP3 (1, 6, 8, 10, 12). It is considered a tumor suppressor, interfering with TGF‑ beta ‑mediated tumor cell invasion and epithelial/mesenchymal transition (5). ZAG can bind beta 3-AR (beta‑3 adrenergic receptor) and can alter beta 3‑AR signaling pathways (8, 10, 13).

Related Research Areas

• Cancer Biomarkers