UBR2
Description
The UBR2 (ubiquitin protein ligase E3 component n-recognin 2) is a protein-coding gene located on chromosome 6.
E3 ubiquitin-protein ligase UBR2 is an enzyme that in humans is encoded by the UBR2 gene. Proteolysis by the ubiquitin-proteasome system controls the concentration of many regulatory proteins. The selectivity of ubiquitylation is determined by ubiquitin E3 ligases, which recognize the substrate's destabilization signal, or degron.
UBR2 is a key component of the N-end rule pathway. It identifies and binds proteins with specific N-terminal residues that signal degradation, ultimately leading to their ubiquitination and breakdown. UBR2 plays a crucial role in chromatin inactivation and transcriptional silencing during meiosis by ubiquitinating histone H2A. It regulates cell growth by binding leucine and acting as a negative regulator of the leucine-mTOR signaling pathway. UBR2 is essential for spermatogenesis and works with Tex19.1 to promote the accumulation of SPO11-dependent recombination foci, driving robust homologous chromosome synapsis. UBR2 polyubiquitinates LIRE1, a LINE-1 retrotransposon-encoded protein, which triggers its degradation and inhibits LINE-1 retrotransposon mobilization. Following activation of NLRP1 by pathogens or damage signals, UBR2 catalyzes the ubiquitination and degradation of the N-terminal part of NLRP1. This ubiquitination promotes the degradation of the N-terminal part and releases the cleaved C-terminal part, leading to NLRP1 inflammasome formation and host cell pyroptosis.
UBR2 is also known as C6orf133, bA49A4.1, dJ242G1.1, dJ392M17.3.
