Lyl1 is required for Lmo2-driven leukemogenesis. (A) Normalization of gene expression in Lmo2;Lyl1−/− thymocytes. A heat map shows the expression levels of the top 40 Lmo2-upregulated genes in wild-type (wt), Lmo2-transgenic (Tg), and Lmo2;Lyl1−/− DN thymocytes. (B) A heat map shows the expression levels of the top 40 Lmo2-downregulated genes in DN thymocytes of mice of the indicated genotypes. Labels are as in (A). (C) Kaplan-Meier survival curve of mice of the indicated genotypes. P < .001 between Lmo2;Lyl1+/− and Lmo2;Lyl−/− (log-rank [Mantel-Cox] test).