UBR1 Recombinant Rabbit mAb (S-4166-11)

UBR1 is an evolutionarily highly conserved E3 ubiquitin ligase encoded by the UBR1 gene and serves as a key recognition component of the N-end rule pathway. This protein contains a RING-type zinc finger domain for binding E2 ubiquitin-conjugating enzymes, as well as a UBR box domain for recognizing substrates bearing destabilizing N-terminal residues (such as basic or bulky hydrophobic amino acids), enabling specific binding to target proteins and mediating their polyubiquitination, ultimately leading to degradation via the ubiquitin-proteasome system. Beyond this classical function, UBR1 can also bind leucine and participate in cell growth regulation as a negative regulator of the leucine-mTOR signaling pathway. At the pathological level, UBR1 gene mutations lead to Johanson-Blizzard syndrome (JBS), an autosomal recessive disorder characterized by congenital pancreatic exocrine insufficiency, nasal wing hypoplasia, intellectual disability, and other multisystem anomalies, in which patients' pancreatic tissues lack UBR1 expression and exhibit destructive pancreatitis beginning in utero. Furthermore, recent studies have revealed that UBR1 plays an important role in regulating glutamate metabolic homeostasis, and its loss of function may lead to abnormal glutamate levels, providing new perspectives for understanding the pathogenesis of JBS