Fig. 6: JUMONJI demethylases are required for the removal of H3K27me3 histone modifications from heat-memory genes under fluctuating temperature conditions.

a Schematic representation of the temperature conditions used. Colored dots indicate the times of different assays: qRT-PCR, red; ChIP-qPCR, gray. Upper, basal thermotolerance condition (+HS); Lower, heat-stress memory condition (+ACC +HS). b Gene expression levels of HSP22 and HSP17.6C in the wild type and jmjq grown under the Nara conditions. Gray dots represent the expression levels of individual samples. One-way ANOVA test; *p < 0.05. Letters above bars indicate significant differences based on a post-hoc Tukey HSD test (p < 0.05). c H3K27me3 levels at HSP22 and HSP17.6C in the wild type and jmjq grown under the Nara conditions. One-way ANOVA test; *p < 0.05. Different letters above bars indicate significant differences based on a post-hoc Tukey HSD test (p < 0.05). d Current model of JUMONJI-mediated heat acclimation. Upon exposure to a triggering heat, plants are acclimatized. Three red and green circles represent H3K27me3 and H3K4me3, respectively. JMJ proteins keep H3K27me3 at lower levels on HSP17.6C and HSP22. The primed plants respond to recurring heat faster or more strongly than non-primed plants do.