NEAT1 regulates Th2 cell development by targeting STAT6 for degradation.

The aim of this study was to investigate the role of lncRNA NEAT1 (nuclear enriched abundant transcript 1) in regulating Th2 cell differentiation. The overexpression vectors of NEAT1 and ITCH, and siRNA targeting NEAT1, EZH2 (enhancer of zeste homolog 2) and STAT6 (signal transducer and activator of transcription 6) were transfected into CD4+T cells. The mRNA expressions of ITCH and STAT6 were analyzed by qRT-PCR and western blotting. The levels of Th2 cytokines were detected by ELISA assay. RIP and ChIP assays were performed to analyze the association between NEAT1 and EZH2 as well as EZH2 and STAT6, respectively. Results showed that NEAT1 significantly repressed ITCH expression and increased STAT6 expression as well as the levels of IL-4, IL-5 and IL-13 in CD4+T cells. RIP and ChIP assays revealed that NEAT1 bound to EZH2 and EZH2 was recruited to the promoter region of ITCH in CD4+T cells. Silencing EZH2 significantly promoted STAT6 for ubiquitination. Furthermore, NEAT targeted STAT6 for ubiquitination and elevated levels of Th2 cytokines by regulating EZH2/ITCH axis. In conclusion, our data indicated that NEAT1 promotes Th2 cell differentiation through the EZH2/ITCH/STAT6 axis.