The MKK3 module integrates nitrate and light signals to modulate secondary dormancy in Arabidopsis thaliana

• 成果类型: Article
• 署名作者: Regnard, Sarah; Otani, Masahiko; Keruzore, Marc; Teinturier, Alizee; Blondel, Marc; Kawakami, Naoto; Krapp, Anne; Colcombet, Jean
• 署名单位: Centre National de la Recherche Scientifique (CNRS); Universite Paris Saclay; Universite Paris Cite; INRAE; Meiji University; CHU Brest; Institut National de la Sante et de la Recherche Medicale (Inserm); Universite de Bretagne Occidentale; INRAE; Universite Paris Saclay; AgroParisTech
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-8577
• DOI: 10.1073/pnas.2403646121
• 发表日期: 2024-10-01
• 关键词: seed dormancy; map kinase; mapkkk18; aba; pathways; proteins

摘要

Seed dormancy corresponds to a reversible blockage of germination. Primary dormancy is established during seed maturation, while secondary dormancy is set up on the dispersed seed, following an exposure to unfavorable factors. Both dormancies are relieved in response to environmental factors, such as light, nitrate, and coldness. Quantitive Trait Locus (QTL) analyses for preharvest sprouting identified MKK3 kinase in cereals as a player in dormancy control. Here, we showed that MKK3 also plays a role in secondary dormancy in Arabidopsis within a signaling module composed of MAP3K13/14/19/20, MKK3, and clade-C MAPKs. Seeds impaired in this module acquired heat- induced secondary dormancy more rapidly than wild- type (WT) seeds, and this dormancy is less sensitive to nitrate, a signal able to release dormancy. We also demonstrated that MPK7 was strongly activated in the seed during dormancy release, especially in response to light and nitrate. This activation was greatly reduced in map3k13/14/19/20 and mkk3 mutants. Finally, we showed that the module was not regulated and apparently did not regulate the genes controlling abscisic acid/ gibberellin acid hormone balance, one of the crucial mechanisms of seed dormancy control. Overall, our work identified a MAPK module controlling seed germination and enlarged the panel of functions of the MKK3- related modules in plants.