Ubiquitin Conjugating Enzyme Ubc9 is Involved in Protein Degradation of Redox Factor-1 (Ref-1).

Redox factor-1 (Ref-1) is a bifunctional protein playing an important role in both cellular redox regulation and DNA apurinic/apyrimidinic sites' repair. To find Ref-1interacting proteins (Rips), a yeast two-hybrid screening was performed by using Ref-1 redox domain as the 'bait', and five positive clones were obtained. One of them (Rip3) was identified to be the ubiquitin-conjugating enzyme Ubc9.