Arabidopsis EARLY FLOWERING3 increases salt tolerance by suppressing salt stress response pathways

作者：Sakuraba Yasuhito; Bulbul Selin; Piao Weilan; Choi Giltsu; Paek Nam Chon

来源：Plant Journal, 2017, 92(6): 1106-1120.

DOI：10.1111/tpj.13747

<jats:title>Summary</jats:title><jats:p>Arabidopsis <jats:styled-content style="fixed-case">EARLY FLOWERING</jats:styled-content>3 (<jats:styled-content style="fixed-case">ELF</jats:styled-content>3) functions in modulating light input to the circadian clock, as a component of <jats:styled-content style="fixed-case">ELF</jats:styled-content>3‐<jats:styled-content style="fixed-case">ELF</jats:styled-content>4‐<jats:styled-content style="fixed-case">LUX ARRHYTHMO</jats:styled-content> (<jats:styled-content style="fixed-case">LUX</jats:styled-content>) evening complex. However, the role of <jats:styled-content style="fixed-case">ELF</jats:styled-content>3 in stress responses remains largely unknown. In this study, we show that <jats:styled-content style="fixed-case">ELF</jats:styled-content>3 enhances plants’ resilience to salt stress: <jats:italic><jats:styled-content style="fixed-case">ELF</jats:styled-content>3</jats:italic>‐overexpressing (<jats:italic><jats:styled-content style="fixed-case">ELF</jats:styled-content>3</jats:italic>‐<jats:styled-content style="fixed-case">OX</jats:styled-content>) plants are salt‐tolerant, while <jats:italic>elf3</jats:italic> mutants are more sensitive to salt stress. The expressions of many salt stress‐ and senescence‐associated genes are altered in <jats:italic>elf3‐1</jats:italic> and <jats:italic><jats:styled-content style="fixed-case">ELF</jats:styled-content>3</jats:italic>‐<jats:styled-content style="fixed-case">OX</jats:styled-content> plants compared with wild‐type. During salt stress, <jats:styled-content style="fixed-case">ELF</jats:styled-content>3 suppresses factors that promote salt stress response pathways, mainly <jats:styled-content style="fixed-case">GIGANTEA</jats:styled-content> (<jats:styled-content style="fixed-case">GI</jats:styled-content>), at the post‐translational level, and <jats:italic><jats:styled-content style="fixed-case">PHYTOCHROME INTERACTING FACTOR</jats:styled-content>4</jats:italic> (<jats:italic><jats:styled-content style="fixed-case">PIF</jats:styled-content>4</jats:italic>), at the transcriptional level. To enhance the salt stress response, <jats:styled-content style="fixed-case">PIF</jats:styled-content>4 directly downregulates the transcription of <jats:italic><jats:styled-content style="fixed-case">JUNGBRUNNEN</jats:styled-content>1</jats:italic> (<jats:italic><jats:styled-content style="fixed-case">JUB</jats:styled-content>1/<jats:styled-content style="fixed-case">ANAC</jats:styled-content>042</jats:italic>), encoding a transcription factor that upregulates the expression of stress tolerance genes, <jats:italic><jats:styled-content style="fixed-case">DREB</jats:styled-content>2A</jats:italic> and <jats:italic><jats:styled-content style="fixed-case">DELLA</jats:styled-content></jats:italic>. Furthermore, <jats:styled-content style="fixed-case">PIF</jats:styled-content>4 directly upregulates the transcription of <jats:italic><jats:styled-content style="fixed-case">ORESARA</jats:styled-content>1</jats:italic> (<jats:italic><jats:styled-content style="fixed-case">ORE</jats:styled-content>1/<jats:styled-content style="fixed-case">ANAC</jats:styled-content>092</jats:italic>) and <jats:italic><jats:styled-content style="fixed-case">SAG</jats:styled-content>29</jats:italic>, positive regulators of salt stress response pathways. Based on our results, we propose that <jats:styled-content style="fixed-case">ELF</jats:styled-content>3 modulates key regulatory components in salt stress response pathways at the transcriptional and post‐translational levels.</jats:p>

• 出版日期2017-12