Lineage-specific stem cells, signals and asymmetries during stomatal development

Abstract

Stomata are dispersed pores found in the epidermis of land plants that facilitate gas exchange for photosynthesis while minimizing water loss. Stomata are formed from progenitor cells, which execute a series of differentiation events and stereotypical cell divisions. The sequential activation of master regulatory basic-helix-loop-helix (bHLH) transcription factors controls the initiation, proliferation and differentiation of stomatal cells. Cell-cell communication mediated by secreted peptides, receptor kinases, and downstream mitogenactivated kinase cascades enforces proper stomatal patterning, and an intrinsic polarity mechanism ensures asymmetric cell divisions. As we review here, recent studies have provided insights into the intrinsic and extrinsic factors that control stomatal development. These findings have also highlighted striking similarities between plants and animals with regards to their mechanisms of specialized cell differentiation.

Reducing Stomatal Density in Barley Improves Drought Tolerance without Impacting on Yield

“…The manipulation of stomatal density has been facilitated by microscopic studies that characterized the cellular stages of the stomatal lineage and molecular studies that revealed the developmental mechanisms controlling their progression (Zhao and Sack, 1999;Han and Torii, 2016). The majority of these studies have been carried out using the genetically tractable, model plant species Arabidopsis.…”

Origins and Evolution of Stomatal Development

“…Although we discuss the origins of stomatal function in the context of these new discoveries, the evolution of guard cell signaling and stomatal behavior has recently been reviewed (Assmann and Jegla, 2016;Chen et al, 2017;Xu et al, 2016). The complex cellular processes underpinning stomatal development, also the subject of several recent reviews (Torii, 2015;Han and Torii, 2016;Simmons and Bergmann, 2016), will be outlined briefly to provide the background to the evo-devo context.…”

Proper division plane orientation and mitotic progression together allow normal growth of maize

“…Alternatively, mutants may have defective specific asymmetric divisions leading to developmental defects (13)(14)(15)(16)(17)(18)(19). Many mutants with general division plane defects have mutations in genes that encode microtubule-associated proteins that disrupt both mitotic and interphase microtubule dynamics.…”