Fig. 3.

KDM3A functions as a transcriptional coactivator of STAT3 in JAK−STAT signaling pathway. (A) Co-IP assay was performed to detect interaction between STAT3 and KDM3A in HeLa cells with or without IL-6 treatment for 2 h. (B) ChIP assays were performed using anti-JAK2, anti−phospho-STAT3, anti−phospho-KDM3A, and anti-H3K9me2 antibodies on the MYC promoters after IL-6 treatment in HeLa cells. **P < 0.01; ***P < 0.001 (Student’s t test). (C) Quantitative RT-PCR analysis of MYC mRNA levels after knockdown of KDM3A by shRNA in HeLa cells following IL-6 treatment. ***P < 0.001 (Student’s t test). (D) Immunoblot analysis of MYC protein levels after knockdown of KDM3A by shRNA following IL-6 treatment in HeLa cells. (E) MYC mRNA levels were measured by quantitative RT-PCR in HeLa cells after rescuing resistant forms of KDM3A WT^R or YA^R in shRNA-mediated KDM3A knockdown cells following IL-6 treatment. *P < 0.05 (Student’s t test). (F) Immunoblot analysis in HeLa cells after rescuing resistant forms of KDM3A WT^R or YA^R in shRNA-mediated KDM3A knockdown cells following IL-6 treatment. (G–I) STAT-responsive M67 promoter luciferase reporter was transfected into HEK293T cells with indicated plasmids. Luciferase reporter activity was measured at 48 h after transfection and normalized by β-galactosidase activity. Values are expressed as mean ± SD for three independent experiments. *P < 0.05; **P < 0.01 (Student’s t test).