FIGURE 1. Efficient HuR ablation in late-stage thymocytes does not alter thymic egress or peripheral T cell distribution.

(A and B) Isolated CD4⁺ T cells from the SP and LNs of HuR-KO mice (distal lck-Cre ROSA HuR^fl/fl) were sorted according to their YFP expression (YFP⁺ versus YFP⁻); CD4⁺ T cells from WT HuR^fl/fl mice were used as control cells. HuR levels were assessed by RT-PCR (A) and Western blot (B). (C) Frequency of DP, CD4 single-positive (CD4⁺ single-positive), and CD8 single-positive (CD8⁺ single-positive) cells among total thymocytes in HuR-KO mice (upper panels) and in YFP⁺ thymocytes (lower panel). (D) Frequency of YFP⁺ (HuR-deficient) cells among DP, CD4⁺ single-positive, and CD8⁺ single-positive thymocytes (upper panel) and representative line graphs of YFP expression (lower panel). (E) Frequency of DP, CD4⁺ single-positive, and CD8⁺ single-positive cells among total splenocytes (upper panel) and YFP⁺ splenocytes (lower panel). (F) Frequency of YFP⁺ (HuR-deficient) cells among DP, CD4⁺ single-positive, and CD8⁺ single-positive splenocytes. Data in (A) and (B) are representative of two independent experiments using at least two mice per group in each experiment. Data in (C)–(F) are representative of four independent experiments consisting of at least two mice per group in each experiment, along with representative flow cytometry plots. Bars represent mean + SEM of two (A and B) or four (D and F) independent experiments. *p < 0.05, ***p < 0.001, ****p < 0.0001, one-way ANOVA with the Tukey multiple-comparisons test or Student t test.