Usp16
Domain
The UBP-type zinc finger binds 3 zinc ions that form a pair of cross-braced ring fingers encapsulated within a third zinc finger in the primary structure. It recognizes the C-terminal tail of free ubiquitin.
Function
Specifically deubiquitinates 'Lys-120' of histone H2A (H2AK119Ub), a specific tag for epigenetic transcriptional repression, thereby acting as a coactivator (PubMed:24034696). Deubiquitination of histone H2A is a prerequisite for subsequent phosphorylation at 'Ser-11' of histone H3 (H3S10ph), and is required for chromosome segregation when cells enter into mitosis (PubMed:24034696). In resting B- and T-lymphocytes, phosphorylation by AURKB leads to enhance its activity, thereby maintaining transcription in resting lymphocytes (PubMed:24034696). Regulates Hox gene expression via histone H2A deubiquitination. Prefers nucleosomal substrates. Does not deubiquitinate histone H2B. Also deubiquitinates non-histone proteins, such as ribosomal protein RPS27A: deubiquitination of monoubiquitinated RPS27A promotes maturation of the 40S ribosomal subunit. Also mediates deubiquitination of tektin proteins (TEKT1, TEKT2, TEK3, TEKT4 and TEKT5), promoting their stability (PubMed:36206347).
Post-translational modifications
Phosphorylated at the onset of mitosis and dephosphorylated during the metaphase/anaphase transition. Phosphorylation by AURKB enhances the deubiquitinase activity.
Sequence Similarities
Belongs to the peptidase C19 family. USP16 subfamily.
Cellular localization
- Nucleus
- Cytoplasm
Alternative names
Ubiquitin carboxyl-terminal hydrolase 16, Deubiquitinating enzyme 16, Ubiquitin thioesterase 16, Ubiquitin-specific-processing protease 16, Usp16