USP may refer to:
The USP (Universelle Selbstladepistole or "universal self-loading pistol") is a semi-automatic pistol developed in Germany by Heckler & Koch GmbH (H&K) of Oberndorf am Neckar as a replacement for the P7 series of handguns.
Design work on a new family of pistols commenced in September 1989 focused primarily on the U.S. commercial and law enforcement markets. USP prototypes participated in rigorous testing alongside H&K's entry in the Offensive Handgun Weapon System (OHWS) program requested by the U.S. Special Operations Command (USSOCOM) and which would later result in the Mk 23 Mod 0. The USP prototypes were then refined in 1992, based on input from the OHWS trials, and the design was finalized in December of the same year. The USP was formally introduced in January 1993 with the USP40 model (the base version) chambered for the increasingly popular .40 S&W cartridge, followed soon by the USP9 (using the 9×19mm Parabellum cartridge), and in May 1995—the USP45 (caliber .45 ACP). In contrast to the ambitious and innovative P7, P9S, and VP70Z designs, the USP uses a more conventional Browning-style cam-locked action, similar to that used in the Hi-Power - but with a polymer frame.
Ubiquitin carboxyl-terminal hydrolase 20 is an enzyme that in humans is encoded by the USP20 gene.
Ubiquitin-specific protease 20 (USP20), also known as ubiquitin-binding protein 20 and VHL protein-interacting deubiquitinating enzyme 2 (VDU2), is a cysteine protease deubiquitinating enzyme (DUB). The catalytic site of USP20, like other DUBs, contains conserved cysteine and histidine residues that catalyse the proteolysis of an isopeptide bond between a lysine residue of a target protein and a glycine residue of a ubiquitin molecule. USP20 is known to deubiquitinate a number of proteins including thyronine deiodinase type 2 (D2), Hypoxia-inducible factor 1α (HIF1α), and β2adrenergic receptor (β2AR).
The USP20 gene is located on chromosome 9 at the locus 9q34.11.
USP20 is a 914-amino acid protein that shows 59% homology with another DUB, USP33. It contains 4 known domains, an N-terminal Zf UBP domain, a catalytic domain containing conserved histidine and cysteine residues, and two C-terminal DUSP domains.