UBE2D4 belongs to the ubiquitin-conjugating enzyme family. Ubiquitin-conjugating enzymes, also known as E2 enzymes and more rarely as ubiquitin-carrier enzymes, perform the second step in the ubiquitination reaction that targets a protein for degradation via the proteasome. UBE2D4 accepts ubiquitin from the E1 complex and catalyzes its covalent attachment to other proteins. In vitro able to promote polyubiquitination using all 7 ubiquitin Lys residues, but may prefer 'Lys-11' and 'Lys-48'-linked polyubiquitination. Recombinant human UBE2D4 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.