Pectin homogalacturonan nanofilament expansion drives morphogenesis in plant epidermal cells

• Published in: Science (American Association for the Advancement of Science) Vol. 367; no. 6481; pp. 1003 - 1007
• Main Authors: Haas, Kalina T, Wightman, Raymond, Meyerowitz, Elliot M, Peaucelle, Alexis
• Format: Journal Article
• Language: English
• Published: United States The American Association for the Advancement of Science 28.02.2020; American Association for the Advancement of Science (AAAS)
• Subjects: Arabidopsis - cytology; Arabidopsis - embryology; Cell Shape; Cell size; Cell Wall - metabolism; Cell walls; Cotyledon - cytology; Cotyledon - embryology; Development Biology; Expansion; Extracellular matrix; Growth Models; Life Sciences; Methylation; Molecular Imaging; Morphogenesis; Organic chemistry; Pectin; Pectins - metabolism; Pectins - ultrastructure; Plant Cells; Plant Development; Plant Epidermis - cytology; Turgor
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.aaz5103

The process by which plant cells expand and gain shape has presented a challenge for researchers. Current models propose that these processes are driven by turgor pressure acting on the cell wall. Using nanoimaging, we show that the cell wall contains pectin nanofilaments that possess an intrinsic expansion capacity. Additionally, we use growth models containing such structures to show that a complex plant cell shape can derive from chemically induced local and polarized expansion of the pectin nanofilaments without turgor-driven growth. Thus, the plant cell wall, outside of the cell itself, is an active participant in shaping plant cells. Extracellular matrix function may similarly guide cell shape in other kingdoms, including Animalia.