Figure 3.

The dynamic timing of plant responses to environmental signals.

(a) Transcription factor (TF) cascades are dynamic over time and can be triggered by an environmental cue.

(b) TF–target interactions underlie the kinetics of TF transcriptional cascades, where higher concentrations of a TF can lead to proportional changes in expression output. In this way, the rate of transcriptional change can be aligned to an environmental signal and explained by simple kinetic models (such as the Michaelis–Menten model; Swift et al., 2020).

(c) Environmental signaling can interface with developmental trajectories. For example, under drought conditions, developing leaves can produce fewer guard cells (Hamanishi et al., 2012).

(d) Transcriptional responses to the environment can also depend on the circadian clock. One key mechanism is ‘gating’, where the expression of an environmentally responsive gene (in orange) is restricted to a certain time of day by the circadian clock (in blue; Millar and Kay, 1996)