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Fluctuating auxin response gradients determine pavement cell-shape acquisition.

ABSTRACT: Puzzle-shaped pavement cells provide a powerful model system to investigate the cellular and subcellular processes underlying complex cell-shape determination in plants. To better understand pavement cell-shape acquisition and the role of auxin in this process, we focused on the spirals of young stomatal lineage ground cells of Arabidopsis leaf epidermis. The predictability of lobe formation in these cells allowed us to demonstrate that the auxin response gradient forms within the cells of the spiral and fluctuates based on the particular stage of lobe development. We revealed that specific localization of auxin transporters at the different membranes of these young cells changes during the course of lobe formation, suggesting that these fluctuating auxin response gradients are orchestrated via auxin transport to control lobe formation and determine pavement cell shape.

SUBMITTER: Grones P

PROVIDER: S-EPMC7355022 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Fluctuating auxin response gradients determine pavement cell-shape acquisition.

Grones Peter P Majda Mateusz M Doyle Siamsa M SM Van Damme Daniël D Robert Stéphanie S

Proceedings of the National Academy of Sciences of the United States of America 20200622 27

Puzzle-shaped pavement cells provide a powerful model system to investigate the cellular and subcellular processes underlying complex cell-shape determination in plants. To better understand pavement cell-shape acquisition and the role of auxin in this process, we focused on the spirals of young stomatal lineage ground cells of <i>Arabidopsis</i> leaf epidermis. The predictability of lobe formation in these cells allowed us to demonstrate that the auxin response gradient forms within the cells o ...[more]

PMID: 32571946

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