UBR-box found in ubiquitin-protein ligase E3-alpha-3 (UBR3) and similar proteins
UBR3 (EC 2.3.2.27), also called ubiquitin-protein ligase E3-alpha-III (E3alpha-III), or N-recognin-3, or zinc finger protein 650, is a RING-type E3 ubiquitin ligase with a function in olfactory and other sensory systems. It negatively regulates the mono-ubiquitination of non-muscle Myosin II, a protein associated with hearing loss in humans. It acts as a positive regulator of Hedgehog (Hh) signaling in Drosophila and vertebrates. It also plays an important role for genome stability by controlling cellular levels of the essential DNA repair protein APE1.