Cell wall arabinan is essential for guard cell function

作者：Louise Jones, Jennifer L. Milne, David A. Ashford, Simon J. McQueen‐Mason · 发表于：Proceedings of the National Academy of Sciences · 年份：2003 · DOI：10.1073/pnas.1832434100 · 被引用次数：334 · 研究领域：Polysaccharides and Plant Cell Walls、Plant Stress Responses and Tolerance、Plant Molecular Biology Research

Stomatal guard cells play a key role in the ability of plants to survive on dry land, because their movements regulate the exchange of gases and water vapor between the external environment and the interior of the plant. The walls of these cells are exceptionally strong and must undergo large and reversible deformation during stomatal opening and closing. The molecular basis of the unique strength and flexibility of guard cell walls is unknown. We show that degradation of cell wall arabinan prevents either stomatal opening or closing. This locking of guard cell wall movements can be reversed if homogalacturonan is subsequently removed from the wall. We suggest that arabinans maintain flexibility in the cell wall by preventing homogalacturonan polymers from forming tight associations.