Based on UBA domains known to possess a high affinity for ubiquitin, Tandem Ubiquitin Binding Entities (TUBEs) have been developed for the isolation and identification of ubiquitinated proteins. TUBEs display up to a 1000-fold increase in affinity for polyubiquitin moieties over the single ubiquitin binding associated domain (UBA). In addition, TUBEs have been demonstrated to protect polyubiquitinated proteins from both deubiquitination and proteasome-mediated degradation, allowing for the detection of relatively low abundant proteins that cannot be detected with current technologies.
