Ubiquitin carboxyl-terminal hydrolase 8

UniProtKB accession:  P50102

Grouped By:  Matching UniProtKB accession

UniProtKB description:  Histone deubiquitinating enzyme component of the transcription coactivator SAGA complex (PubMed:14563679, PubMed:14660634, PubMed:25216679, PubMed:28918903). SAGA acts as a general cofactor required for essentially all RNA polymerase II transcription (PubMed:10864329, PubMed:25216679, PubMed:28918903). At the promoters, SAGA is required for transcription pre-initiation complex (PIC) recruitment. It influences RNA polymerase II transcriptional activity through different activities such as TBP interaction (via core/TAF module) and promoter selectivity, interaction with transcription activators (via Tra1/SPT module), and chromatin modification through histone acetylation (via HAT module) and deubiquitination (via DUB module) (PubMed:31969703). SAGA preferentially acetylates histones H3 (to form H3K9ac, H3K14ac, H3K18ac and H3K23ac) and H2B and deubiquitinates histone H2B (PubMed:10026213, PubMed:14660634, PubMed:15657441). SAGA interacts with DNA via upstream activating sequences (UASs) (PubMed:28918903). Also identified in a modified version of SAGA named SALSA or SLIK (PubMed:12446794, PubMed:14660634, PubMed:15647753). The cleavage of SPT7 and the absence of the SPT8 subunit in SLIK neither drive any major conformational differences in its structure compared with SAGA, nor significantly affect HAT, DUB, or DNA-binding activities (PubMed:33864814). Within the DUB module, the correctly positioned zinc finger domains of SGF11 and SGF73 are both required to fully activate the ubiquitin hydrolase UBP8 (PubMed:15657442, PubMed:20434206). The DUB module is also linked to the splicing efficiency of many transcripts (PubMed:23209445).