PIAS1: Functions as an E3-type small ubiquitin-like modifier (SUMO) ligase, stabilizing the interaction between UBE2I and the substrate, and as a SUMO-tethering factor. Plays a crucial role as a transcriptional coregulation in various cellular pathways, including the STAT pathway, the p53 pathway and the steroid hormone signaling pathway. In vitro, binds A/T-rich DNA. The effects of this transcriptional coregulation, transactivation or silencing, may vary depending upon the biological context. Together with PRMT1, may repress STAT1 transcriptional activity, in the late phase of interferon gamma (IFN-gamma) signaling. Interacts with NCOA2 and AR. Interacts with NR2C1; the interaction promotes its sumoylation. Interacts with DDX21, CSRP2, AXIN1, JUN, UBE2I, SUMO1, SATB2, PLAG1, TP53 and STAT1 (dimer), following IFNA1-stimulation. Interacts with SP3 (preferentially when SUMO-modified). Interacts with KLF8; the interaction results in SUMO ligation and repression of KLF8 transcriptional activity and of its cell cycle progression into G(1) phase. Interacts with STAT1. Interacts with CHUK/IKKA; this interaction induces PIAS1 phosphorylation. Interacts with PTK2/FAK1; the interaction promotes its sumoylation. Interacts with DDX5. Expressed in numerous tissues with highest level in testis. Belongs to the PIAS family.
Protein type: EC 6.3.2.-; Transcription, coactivator/corepressor; SUMO conjugating system; Nuclear receptor co-regulator
Chromosomal Location of Human Ortholog: 15q
Cellular Component: nucleoplasm; nucleus; PML body
Molecular Function: enzyme binding; protein binding; SUMO ligase activity; transcription corepressor activity
Biological Process: JAK-STAT cascade; positive regulation of proteasomal ubiquitin-dependent protein catabolic process; positive regulation of protein sumoylation; protein sumoylation; regulation of cell proliferation
Show more