Figure 2.

Overview of two examples where environmental stimuli trigger short or long-distance changes in chromatin organization. (a) Light mediates changes in histone modifications, gene relocation to the nuclear periphery and an increase in nuclear size and DNA content through the action of photoreceptors and light signaling components [35^••,42,44^••,64,65]. Light-induced changes in nuclear architecture lead to the transcriptional activation of light-responsive genes essential for photomorphogenesis (CAB, RBCS, GUN5) [35^••,44^••]. (b) Prolonged cold temperatures are required for flowering initiation by silencing of the negative regulator of flowering FLC. Prolonged cold triggers FLC gene clustering and disruption of gene loop formation followed by epigenetic silencing of FLC through the deposition of repressive histone marks [53,54^••].