Figure 1. miR-181a deficiency impairs histone expression and cell cycle progression in murine antiviral responses.

(A–E) Equal numbers of congenically marked WT and miR-181a^–/– YFP⁺ SMARTA cells were cotransferred into B6 mice before LCMV infection. (A) Experimental scheme (left), representative flow plots of WT and miR-181a^–/– SMARTA cells (middle), and SMARTA frequencies (right, mean ± SEM). (B and C) RNA-seq of WT and miR-181a^–/– SMARTA CD4⁺ T cells on day 7 after LCMV infection. (B) GSEA of cell cycle gene signature in WT relative to miR-181a^–/– SMARTA cells. (C) Volcano plot of core histone genes (red indicates adjusted P < 0.05). (D) Immunoblotting for histones in WT and miR-181a^–/– SMARTA cells on day 7 after LCMV infection. (E) On day 5 after LCMV infection, recipient mice received BrdU for 1 hour prior to spleen harvest. Representative flow plots of BrdU incorporation and DNA content and summarized frequencies (mean ± SEM). (F and G) WT and miR-181a^–/– mice infected with LCMV were injected with BrdU. (F) Number of D^b LCMV GP33-tetramer⁺ CD8⁺ T cells (mean ± SEM). (G) Representative flow plots of BrdU incorporation and DNA content in tetramer⁺ CD8⁺ T cells (left) and summary of frequencies (right, mean ± SEM). (H) GSEA of the p53-induced gene set in WT relative to miR-181a^–/– SMARTA cells. (I) Immunoblots for p53 on day 7 SMARTA cells and summary data of mean normalized intensities. (J) Immunoblots of SMARTA cells on day 7 after LCMV infection. Data are representative of 3 experiments with 3 to 5 mice per group (A and D), 1 experiment with 4 mice per group (B, C, and H), or representative of 2 experiments with 2 to 6 mice per group (E–G, I, and J). Comparison by 2-tailed, paired (A, E, and I) or unpaired Student’s t test (F and G). *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001. NS, not significant.