Induction of LMO2 gene expression by E2A-HLF. (A) Induction of E2A-HLF expression. Lysates of wild type (WT) and a clone of E2A-HLF–transfected 697 cells as well as UOC-B1 cells harvested at the indicated time after the addition of zinc were blotted with an anti-E2A serum. Gray, white, and black arrowheads indicate E2A-Pbx1, E2A, and E2A-HLF, respectively. (B) Time course analysis of LOM2 gene expression after induction of E2A-HLF. Levels of LMO2 transcripts were quantified by real-time RT-PCR using the primers for exons 4 and 5, normalized by GAPDH gene expression as an internal control. Changes in fold induction of LMO2 gene expression level to that in wild type 697 cells cultured in the absence of zinc are shown as the mean ± SE of triplicate samples. (C) Time course analysis of LOM2 gene expression derived from the distal and proximal promoters after induction of E2A-HLF. Levels of LMO2 transcripts in E2A-HLF–transfected 697 cells cultured in the presence of zinc were semiquantified by real-time RT-PCR with the specific primers for LMO2 transcripts sourced at the distal promoter and for total LMO2 transcripts. Changes in fold induction of LMO2 gene expression level to that in E2A-HLF–transfected cells cultured in the absence of zinc are shown as the mean ± SE of triplicate samples. Asterisks indicate the significant gene induction determined by t-test. (D) Schematic diagram of mutants of E2A-HLF. (E) Western blot analysis of mutants of E2A-HLF. Lysates of UOC-B1 cells and wild-type (WT) and clones of 697 cells transfected with E2A-HLF, BX, and ΔAD1/ΔLH cultured in the absence or presence of zinc for 24 hours were blotted with E2A (left panel) and HLF(C) (right panel) antisera. (F) LMO2 gene expression in mutant E2A-HLF–transfected 697 cells. Wild-type (WT) and transfectants of 697 cells were cultured in the absence or presence of zinc for 24 hours, and the levels of LMO2 transcripts were quantified by real-time RT-PCR. Changes in fold induction of LMO2 gene expression level to that in wild-type 697 cells cultured in the absence of zinc are shown as the mean ± SE of triplicate samples.