UBE2V1UBE2V2

UBE2V1 and UBE2V2 are closely related proteins that belong to the family of ubiquitin-conjugating enzymes, also known as E2 enzymes. They are involved in the ubiquitination pathway, a crucial cellular process that tags proteins for degradation, alters their activity, or influences their cellular localization. Both proteins share significant sequence similarity and often function as partners in various biological processes.

UBE2V1, also known as UbcH6 variant, is an E2 enzyme that lacks intrinsic catalytic activity but partners with E2 enzymes like UBE2N (Ubc13) to facilitate specific types of polyubiquitination. UBE2V2, similarly, acts as an E2 variant that forms heterodimers with UBE2N, enabling the formation of Lys63-linked polyubiquitin chains. These chains are predominantly involved in DNA repair, signal transduction, and immune responses rather than targeting proteins for proteasomal degradation.

Structurally, both UBE2V1 and UBE2V2 are characterized by their conserved ubiquitin-conjugating enzyme fold but lack the active site cysteine residue present in other E2 enzymes. Instead, they modulate ubiquitination activities through their ability to form heterodimers with catalytic E2 enzymes, influencing the specificity and outcome of ubiquitin chain formation.

Functionally, the UBE2V1/UBE2V2 complex plays a critical role in immune signaling pathways, particularly in the activation of NF-κB signaling, and in maintaining genomic stability. Dysregulation of these proteins has been implicated in various disease processes, including cancer and immune disorders. Overall, UBE2V1 and UBE2V2 are vital components of the ubiquitination machinery with key roles in cellular homeostasis and signaling.