Fig. 4.

NR4A3 is an early regulator of the CD8⁺ T cell memory gene signature. (A) Volcano plot of genes differentially expressed in Nr4a3^+/+ and Nr4a3^−/− OT-I cells assessed by RNA-seq at day 3 postinfection with Lm-OVA. Indicated in black, genes P adj <0.05. Indicated in red, genes P adj <0.05 and |FC|>1.5. (B) GSEA of the NR4A3-regulated transcriptome reveals enrichment of memory signatures. (C) Heat map illustrating the relative expression in Nr4a3^+/+ and Nr4a3^−/− OT-I cells of genes encoding for selected transcription factors controlling CD8⁺ T cell differentiation. At day 7 post-Lm-OVA infection, the expression of transcription factors known to be involved in CD8⁺ T cell memory generation was measured by FACS (D) or by qRT-PCR (E) in spleens. (F) Il2ra transcription by day-3 OT-I effectors (data from RNA-seq). (G) At day 3 post-Lm-OVA infection, expression of CD25 on Nr4a3^+/+ and Nr4a3^−/− OT-I cells was measured by flow cytometry. Endo: total CD8⁺CD45.2⁻ endogenous cells. Each dot represents one mouse. Data are from two (A, C, E, and G) or at least three independent experiments (D). A Mann–Whitney unpaired t test (F), when a low number of experimental samples were available, was used and an unpaired Student’s t test, with a Welch’s correction when applied, was used for the other two-group comparison: *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001.