Mechanochemical feedback mediates tissue bending required for seedling emergence

第一作者：Kristoffer Jonsson

第一单位：瑞典农业科学大学

通讯作者：Rishikesh P. Bhalerao

 Abstract 

大背景：Tissue bending is vital to plant development, as exemplified by apical hook formation during seedling emergence by bending of the hypocotyl.

大问题：How tissue bending is coordinated during development remains poorly understood, especially in plants where cells are attached via rigid cell walls.

小背景：Asymmetric distribution of the plant hormone auxin underlies differential cell elongation during apical hook formation.

小问题：Yet the underlying mechanism remains unclear.

主要发现：Here, we demonstrate spatial correlation between asymmetric auxin distribution, methylesterified homogalacturonan (HG) pectin, and mechanical properties of the epidermal layer of the hypocotyl in Arabidopsis.

结果1-机械化学：Genetic and cell biological approaches show that this mechanochemical asymmetry is essential for differential cell elongation.

结果2-生长素与HG甲酯化：We show that asymmetric auxin distribution underlies differential HG methylesterification, and conversely changes in HG methylesterification impact the auxin response domain.

结论：Our results suggest that a positive feedback loop between auxin distribution and HG methylesterification underpins asymmetric cell wall mechanochemical properties to promote tissue bending and seedling emergence.

 通讯作者 

**Marc Libault**

doi: https://doi.org/10.1016/j.cub.2020.12.016

Journal: Current Biology

Published date: Jan 07, 2021