Purity: > 90% by SDS - PAGE Format: Liquid. In 20mM Tris-HCl buffer (pH 8.0) containing 0.15M NaCl, 10% glycerol, 1mM DTT . AP-3 complex subunit sigma-1, also known as AP3S1, is a Part of the AP-3 complex, an adapter-related complex which is not clathrin-associated. The complex is associated with the Golgi region as well as more peripheral structures. It facilitates the budding of vesicles from the Golgi membrane and may be directly involved in trafficking to lysosomes. Recombinant human AP3S1 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.