UBE3A ligase E3A) is a 101 kDa E3 Ligase enzyme. The protein contains a C4 type zinc-finger and belongs to the HECT-type E3 ligase family with its site cystein located at aa 843. UBE3A is involved in diseases. It is used by the oncoprotein E6 (HPV) to trigger p53 degradation enabling cervical cancer. It appears to be involved in prostate cancer, linked to Angelman Syndrome, and elevated expression is correlated with disorders. Furthermore, recent findings revealed a high binding site RAZUL (Rpn10 AZUL-binding domain) with the proteasome and with Rpn10 (PSMD4) its involvement in the of many proteins for 26S proteasome Knockdown of UBE3A leads to a in proteins at the proteasome. It is hypothesized, that UBE3A may belong to a subset of E3 ligases by the proteasome. This recombinant protein (human) has been expressed and from Sf9 insect cells and has a C-terminal 8x His-Tag.