. "Reviewed: Abdul-Sater, AA, Schindler, C, 2010-08-17"^^ . "Edited: Garapati, P V, 2010-07-07"^^ . "Authored: Garapati, P V, 2010-06-08"^^ . "PIAS1 protein interacts directly with phoshorylated STAT1 dimers and inhibit the transcriptional activity of STAT1 by blocking the DNA-binding domain of STAT1. It has also been suggested that PIAS proteins might regulate transcription by promoting small ubiquitin-related modifier (SUMO1) conjugation of STAT1. The significance of STAT1 sumoylation in regulating STAT1 activity is controversial and needs to be clarified."^^ . . . . . . . . "PIAS1 binds p-STAT1 dimer"^^ . . . . .