Ubiquitin-conjugating enzyme E2 K

Ubiquitin-conjugating enzyme E2 K (UBE2K) is an E2 ubiquitin-conjugating enzyme that catalyzes the covalent transfer of ubiquitin to target proteins, primarily synthesizing Lys-48-linked polyubiquitin chains and elongating monoubiquitinated substrates (UniProt: P61086). The protein mediates selective protein degradation pathways including endoplasmic reticulum-associated degradation (ERAD) of misfolded proteins and ubiquitinates several substrates including huntingtin, p53, NFKB1, and viral proteins.

UBE2K functions in protein quality control and cellular stress responses across diverse tissues. No primary disease associations are documented in the UniProt record (UniProt: P61086), though the protein's roles in protein misfolding degradation and apoptosis regulation implicate it in cellular homeostasis.

In Alzheimer's Disease, UBE2K is significantly up-regulated in post-mortem AD brain tissue relative to age-matched controls (mean log2 fold-change = 0.94; Chaparral AD proteomics). This up-regulation, detected via TMT-labeled quantitative proteomics across subcellular fractions, may reflect elevated protein quality control demands or altered ubiquitin-proteasome system activity in response to AD-associated protein aggregation and neurodegeneration.