IL1B and infection: Unstimulated chondrocytes exhibited various mRNA levels of the different ZC3H12 family members (Fig. 1b); our RT-PCR (Supplementary Fig. 1A and B) and quantitative RT-PCR (qRT-PCR) (Fig. 1c–e) analyses revealed that Regnase-1 was upregulated by IL-1β treatment (Fig. 1c) or infection of Ad-HIF-2α (Fig. 1d) or Ad-ZIP8 (Fig. 1e).