Temperature- dependent polar lignification of a seed coat suberin layer promoting dormancy in Arabidopsis thaliana
成果类型：
Article
署名作者：
Hyvarinen, Lena; Fuchs, Christelle; Utz-Pugin, Anne; Gully, Kay; Megies, Christian; Holbein, Julia; Iwasaki, Mayumi; Demonsais, Lara; Capitao, Maria Beatriz; Barberon, Marie; Franke, Rochus B.; Nawrath, Christiane; Loubery, Sylvain; Lopez-Molina, Luis
署名单位：
University of Geneva; University of Lausanne; University of Bonn; University of Geneva
刊物名称：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
ISSN/ISSBN：
0027-14330
DOI：
10.1073/pnas.2413627122
发表日期：
2025-02-11
关键词：
lipid polyester
brassica-napus
abscisic-acid
lignin
proteins
root
polymerization
biosynthesis
deposition
EVOLUTION
摘要：
The seed is a landmark plant adaptation where the embryo is sheltered by a protective seed coat to facilitate dispersion. In Arabidopsis, the seed coat, derived from ovular integuments, plays a critical role in maintaining dormancy, ensuring germination occurs during a favorable season. Dormancy is enhanced by cold temperatures during seed development by affecting seed coat permeability through changes in apoplastic barriers. However, their localization and composition are poorly understood. This study identifies and investigates a polar barrier in the seed coat's outer integument (oi1) cells. We present histological, biochemical, and genetic evidence showing that cold promotes polar seed coat lignification of the outer integument 1 (oi1) cells and suberization throughout the entire oi1 cell boundary. The polar oi1 barrier is regulated by the transcription factors MYB107 and MYB9. MYB107, in particular, is crucial for the lignified polar oi1 barrier formation under cold temperatures. The absence of the oi1 barrier in mutant seeds correlates with increased permeability and reduced dormancy. Our findings elucidate how temperature- induced modifications in seed coat composition regulate dormancy, highlighting the roles of suberin and lignin in this process.