Fig. 1.

Tet1 negatively correlates with Lhb expression and is down-regulated by GnRH and gonadal steroids. (A and B) qPCR analyses in (A) primary gonadotropes from immature (6 d) or mature (8–14 wk) mice or (B) αT3-1 and LβT2 cells; mRNA levels are relative to immature mice or αT3-1 cells (n = 3–9). A t test was used to compare levels of the same gene between cells (***P < 0.001). (C) TET1 (red) in the adult pituitary of GRIC-GFP mice; GnRHR⁺ cells appear green. (Scale bar: 100 µm). (Bottom Left) Enlargement of boxed region; (Bottom Right) CGA (red) in the same pituitary. (Scale bars: 50 µm.) (D) Tet1 levels in cell lines and primary cells from immature mice after exposure to GnRH in culture; αT3-1 cells were also exposed to forskolin or PMA; alternatively treated with H89 or transfected with dominant-negative (DN) PKA with and without GnRH exposure (n = 2–6; *P < 0.05 and ***P < 0.001; NS indicates P > 0.05; all means shown relative to untreated controls). (E) αT3-1 cells or (F) primary gonadotropes from immature mice were exposed to E₂ or DHT; Tet1 mRNA levels are presented as in Fig. 1D (n = 4–6). (G and H) Tet1 and Lhb mRNA levels in gonadotropes 10 d after (G) ovariectomy (n = 4) or (H) castration (n = 8) shown relative to age-matched intact controls (Fig. S1).