Ubiquitin-Specific Peptidase 2 (USP2) is a deubiquitinating enzyme (DUB) belonging to the USP family, which plays a critical role in regulating protein stability and function by cleaving ubiquitin chains from target proteins. USP2 is involved in diverse cellular processes, including cell cycle progression, apoptosis, DNA repair, and immune responses. It has two major isoforms, USP2a and USP2b, with USP2a being the more extensively studied. USP2a is known to stabilize key proteins such as MDM2 (a negative regulator of p53) and fatty acid synthase (FASN), linking it to cancer progression and metabolism. Dysregulation of USP2 has been implicated in various cancers, neurodegenerative diseases, and inflammatory conditions, making it a potential therapeutic target.Besides,Ubiquitin Specific Peptidase 14 (USP14) has been identified as an interactor of USP2, thus a functional binding ELISA assay was conducted to detect the interaction of recombinant human USP2 and recombinant human USP14 . Briefly, biotin-linked USP2 were diluted serially in PBS, with 0.01% BSA (pH 7.4). Duplicate samples of 100μl were then transferred to USP14-coated microtiter wells and incubated for 1h at 37℃. Wells were washed with PBST 3 times and incubation with Streptavidin-HRP for 30min, then wells were aspirated and washed 5 times. With the addition of substrate solution, wells were incubated 15-25 minutes at 37℃. Finally, add 50μl stop solution to the wells and read at 450nm immediately. The binding activity of ecombinant human USP2 and recombinant human USP14 was shown in Figure 1, the EC50?for this effect is 0.724 μg/mL.