TY - JOUR

T1 - Shank-localized cell wall growth contributes to Arabidopsis root hair elongation

AU - Herburger, Klaus

AU - Schoenaers, Sébastjen

AU - Vissenberg, Kris

AU - Mravec, Jozef

N1 - Publisher Copyright: © 2022, The Author(s), under exclusive licence to Springer Nature Limited.

PY - 2022

Y1 - 2022

N2 - Root hairs are highly elongated tubular extensions of root epidermal cells with a plethora of physiological functions, particularly in establishing the root–rhizosphere interface. Anisotropic expansion of root hairs is generally thought to be exclusively mediated by tip growth—a highly controlled apically localized secretion of cell wall material-enriched vesicles that drives the extension of the apical dome. Here we show that tip growth is not the only mode of root hair elongation. We identified events of substantial shank-localized cell wall expansion along the polar growth axis of Arabidopsis root hairs using morphometric analysis with quantum dots. These regions expanded after in vivo immunolocalization using cell wall-directed antibodies and appeared as distinct bands that were devoid of cell wall labelling. Application of a novel click chemistry-enabled galactose analogue for pulse chase and real-time imaging allowed us to label xyloglucan, a major root hair glycan, and demonstrate its de novo deposition and enzymatic remodelling in these shank regions. Our data reveal a previously unknown aspect of root hair growth in which both tip- and shank-localized dynamic cell wall deposition and remodelling contribute to root hair elongation.

AB - Root hairs are highly elongated tubular extensions of root epidermal cells with a plethora of physiological functions, particularly in establishing the root–rhizosphere interface. Anisotropic expansion of root hairs is generally thought to be exclusively mediated by tip growth—a highly controlled apically localized secretion of cell wall material-enriched vesicles that drives the extension of the apical dome. Here we show that tip growth is not the only mode of root hair elongation. We identified events of substantial shank-localized cell wall expansion along the polar growth axis of Arabidopsis root hairs using morphometric analysis with quantum dots. These regions expanded after in vivo immunolocalization using cell wall-directed antibodies and appeared as distinct bands that were devoid of cell wall labelling. Application of a novel click chemistry-enabled galactose analogue for pulse chase and real-time imaging allowed us to label xyloglucan, a major root hair glycan, and demonstrate its de novo deposition and enzymatic remodelling in these shank regions. Our data reveal a previously unknown aspect of root hair growth in which both tip- and shank-localized dynamic cell wall deposition and remodelling contribute to root hair elongation.

U2 - 10.1038/s41477-022-01259-y

DO - 10.1038/s41477-022-01259-y

M3 - Letter

C2 - 36303011

AN - SCOPUS:85140851425

VL - 8

SP - 1222

EP - 1232

JO - Nature Plants

JF - Nature Plants

SN - 2055-026X

ER -