Overexpression of FOG-1 induced the downregulation of β-chain transcription and surface expression of FcϵRI in PT18 cells. (A) Western blot analysis of transfected cells. PT18 cells were transfected with pCR-FOG-1 or pCR3.1 by electroporation and cultured in the presence of G418 for longer than 2 weeks. Lysates (1 × 106 cells per lane) were analyzed using anti-FOG-1, anti-GATA-1, or anti-YY1 Abs. (B) Surface expression of FcϵRI on transfectants. PT18 cells transfected with pCR-FOG-1 (FOG-1, bold line) or empty vector (mock, solid line) were stained with FITC-conjugated mouse IgE antibody. FOG-1 transfectants without antibody are shown by the dotted line. (C) Quantitative real-time RT-PCR analysis of transfected cells. The mRNA levels of FOG-1, α-chain, and β-chain in FOG-overproducing cells were represented as the ratio to that of mock transfectants. □ indicates PT18 cells transfected with pCR3.1; and ▪, PT18 cells transfected with pCR-FOG-1. Data are represented as the average ± SD of triplicate samples.
