Inhibitory Effects of a Novel PPAR-γ Agonist MEKT1 on Pomc Expression/ACTH Secretion in AtT20 Cells

Figure 10

Effects of MEKT1 on the interaction between Nur77/Nurr1 and NurRE, Tpit and TpitRE, and Nur77 and NBRE on Pomc promoter (a) in AtT20 cells. Effects of MEKT1 on the interaction between Nur77/Nurr1 and NurRE (b), Tpit and TpitRE (c), and Nur77 and NBRE (d) on Pomc promoter examined by ChIP assay using NurRE, TpitRE, and NBRE primer. ChIP assay was carried out using digested chromatin extracted from the cells cultured in the presence of either 10 μM MEKT1 or 0.1% DMSO (control) for 24 hours. Chromatin fragments were immunoprecipitated either by normal rabbit IgG (negative control), anti-Nur77/Nurr1 antibody, or anti-Tpit (anti TBX 19) antibody. Purified DNA was analyzed by qPCR using primers specific for NurRE, TpitRE, and NBRE containing sequence on Pomc promoter. The primer product sizes of NurRE, TpitRE, and NBRE were 211 bp, 146 bp, and 102 bp, respectively. Immunoprecipitated DNA was amplified by qPCR and then normalized to the values obtained after amplification of immunoprecipitated 1% input DNA. Data represent mean ± SEM (). NS means “not significant.” , and significantly different from the level of control group.

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