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Abstract BackgroundLike all plant cells, the guard cells of stomatal complexes are encased in cell walls that are composed of diverse, interacting networks of polysaccharide polymers. The properties of these cell walls underpin the dynamic deformations that occur in guard cells as they expand and contract to drive the opening and closing of the stomatal pore, the regulation of which is crucial for photosynthesis and water transport in plants. ScopeOur understanding of how cell wall mechanics are influenced by the nanoscale assembly of cell wall polymers in guard cell walls, how this architecture changes over stomatal development, maturation and ageing and how the cell walls of stomatal guard cells might be tuned to optimize stomatal responses to dynamic environmental stimuli is still in its infancy. ConclusionIn this review, we discuss advances in our ability to probe experimentally and to model the structure and dynamics of guard cell walls quantitatively across a range of plant species, highlighting new ideas and exciting opportunities for further research into these actively moving plant cells.
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Establishing asymmetry: stomatal division and differentiation in plants
Summary In the leaf epidermis, stomatal pores allow gas exchange between plants and the environment. The production of stomatal guard cells requires the lineage cells to divide asymmetrically. In this Insight review, we describe an emerging picture of how intrinsic molecules drive stomatal asymmetric cell division in multidimensions, from transcriptional activities in the nucleus to the dynamic assembly of the polarity complex at the cell cortex. Given the significant roles of stomatal activity in plant responses to environmental changes, we incorporate recent advances in external cues feeding into the regulation of core molecular machinery required for stomatal development. The work we discuss here is mainly based on the dicot plantArabidopsis thalianawith summaries of recent progress in the monocots.
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- PAR ID:
- 10447575
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 232
- Issue:
- 1
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 60-67
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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