 When it was discovered that PIAS proteins did far more than simply inhibit STATs, it was proposed that the PIAS acronym should stand for Pleiotropic Interactors Associated with SUMO based on their association with SUMO proteins.Additionally, E3 SUMO-protein ligase PIAS is an alternative name for PIAS proteins.The discovery of PIAS3L, an isoform of PIAS3, was published in 2003.