Gfi1b suppresses Gfi1 and Gata3 expression in a SNAG domain-dependent manner. (A) Fold repression of the indicated genes after infection of 0531 (▪) or 1.F9 (⊡) with MigR1-Gfi1b as compared to MigR1 virus, as determined by Affymetrix 430 2.0 gene arrays. Gfi1b-mediated repression was confirmed by QPCR for (B) Gfi1 or (C) Gata3 mRNA after infection of 0531 or 1.F9 cells with MigR1, MigR1-Gfi1b, or MigR1-ΔSNAG. (D) Western blot analysis of Gfi1 and Gata3 protein in 1.F9 and 0531 cells expressing MigR1 (−) or MigR1-Gfi1b retrovirus. (E) QPCR analysis of Gfi1b and Gata3 mRNA isolated from primary E2A^−/− lymphomas (labeled A-D). Data are presented as the difference in C_T value between HPRT and Gfi1b () or Gata3 (▪). The standard error of triplicate measurements is shown for panels B, C, and E.