Related Experiment Video
Updated: Sep 11, 2026

A High Resolution Method to Monitor Phosphorylation-dependent Activation of IRF3
Published on: January 24, 2016
PIAS3 induces SUMO-1 modification and transcriptional repression of IRF-1
Koji Nakagawa1, Hideyoshi Yokosawa
1Department of Biochemistry, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
Abstract:
Interferon regulatory factor-1 (IRF-1) is a transcriptional activator that is involved in interferon response, regulation of cell growth and oncogenesis. To try to identify the molecules that regulate the function of IRF-1, we performed yeast two-hybrid screening and isolated protein inhibitor of activated STAT3 (PIAS3) as an IRF-1-binding protein. This protein was also found to bind with small ubiquitin-related modifier-1 (SUMO-1) and ubiquitin-conjugating enzyme 9, an E2 in the SUMO-1-conjugating system. Co-expression of PIAS3 induced SUMO-1 modification of IRF-1 in a RING finger domain-dependent manner and also repressed transcriptional activity of IRF-1. Thus, PIAS3 functions as a SUMO-1 ligase for IRF-1 and also as a repressor of IRF-1 transcriptional activity.
Related Concept Videos
siRNA - Small Interfering RNAs
In the cytoplasm, siRNA is processed from a double-stranded RNA, which comes from either endogenous DNA transcription or exogenous sources like a virus. This double-stranded RNA is then cleaved by the ATP-dependent...
piRNA - Piwi-interacting RNAs
Phosphoinositides and PIPs
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
Experimental RNAi
Regulation of the Unfolded Protein Response
The JAK-STAT Signaling Pathway

