E3 SUMO-protein ligase PIAS2 (IPR027228)

Short name: PIAS2

Overlapping homologous superfamilies


Family relationships



SUMO proteins are ubiquitin like proteins that are covalently attached to and detached from other proteins in cells to modify their function. SUMO is first activated in an ATP-dependent reaction by formation of a thioester bond with an E1 (SUMO-activating) enzyme and then transferred to the SUMO conjugating (E2) enzyme Ubc9. Ubc9 catalyses the formation of an isopeptide bond between the C-terminal of SUMO and the amino group of lysine in the target protein. Sumoylated proteins can be targeted for different cellular processes, such as nuclear transport, transcriptional regulation, apoptosis, and protein stability [PMID: 12383504].

PIAS2 is an E3-type small ubiquitin-like modifier (SUMO) ligase, stabilising the interaction between Ubc9 and the substrate, and is a SUMO-tethering factor. It 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. The effects of this transcriptional coregulation, transactivation or silencing may vary depending upon the biological context and PIAS2 isoform studied. However, it seems to be mostly involved in gene silencing. It binds to sumoylated ELK1 and enhances its transcriptional activity by preventing recruitment of HDAC2 by ELK1, thus reversing SUMO-mediated repression of ELK1 transactivation activity [PMID: 15920481, PMID: 15976810].

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0019789 SUMO transferase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.