Synthetic alleles to study MUTE-dependent molecular transitions in stomatal development.

Stomatal abundance sets plants' potential for gas exchange, impacting photosynthesis and transpiration and, thus, plant survival and growth. Stomata originate from cell lineages initiated by asymmetric divisions of protodermal cells, producing meristemoids that develop into guard cell pairs. The transcription factors SPEECHLESS, MUTE, and FAMA are essential for stomatal lineage development, sequentially driving cell division and differentiation events.