UBR-box found in ubiquitin-protein ligase E3-alpha-1 (UBR1) and similar proteins
UBR1 (EC 2.3.2.27), also called ubiquitin-protein ligase E3-alpha-I (E3alpha-I), or N-recognin-1, is a RING-type E3 ubiquitin ligase of the Arg/N-end rule degradation pathway. It recognizes and binds to proteins bearing specific N-terminal residues that are destabilizing according to the N-end rule, leading to their ubiquitination and subsequent degradation. Deficiency of UBR1 causes Johanson-Blizzard syndrome.
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