Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, People's Republic of China.
Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, People's Republic of China
Plant Physiol. 2019 Apr;179(4):1844-1860. doi: 10.1104/pp.18.01466. Epub 2019 Feb 5.
Arabidopsis () GARP (Golden2, ARR-B, Psr1) family transcription factors, GOLDEN2-LIKE1 and -2 (GLK1/2), function in different biological processes; however, whether and how these transcription factors modulate the response to abscisic acid (ABA) remain unknown. In this study, we used a double mutant to examine the role of GLK1/2 in the ABA response. The double mutant displayed ABA-hypersensitive phenotypes during seed germination and seedling development and an osmotic stress-resistant phenotype during seedling development. Genome-wide RNA sequencing analysis of the double mutant revealed that GLK1/2 regulate several ABA-responsive genes, including , in the presence of ABA. Chromatin immunoprecipitation and gel retardation assays showed that GLK1/2 directly associate with the promoter via the recognition of a consensus sequence. Additionally, RNA sequencing analysis of the double mutant and single mutant revealed that GLK1/2 and WRKY40 control a common set of downstream target genes in response to ABA. Furthermore, results of a genetic interaction test showed that the triple mutant displayed similar ABA hypersensitivity to the single mutant and the double mutant, while the ( mutant) quadruple mutant displayed similar ABA hyposensitivity to the single mutant. Based on these results, we propose that the GLK1/2-WRKY40 transcription module plays a negative regulatory role in the ABA response.
拟南芥（Arabidopsis）GARP（Golden2，ARR-B，Psr1）家族转录因子，GLK1/2（Golden2-LIKE1 和 -2），在不同的生物学过程中发挥作用；然而，这些转录因子是否以及如何调节对脱落酸（ABA）的反应尚不清楚。在本研究中，我们使用 双突变体来研究 GLK1/2 在 ABA 反应中的作用。在种子萌发和幼苗发育过程中， 双突变体表现出 ABA 超敏表型，在幼苗发育过程中表现出耐渗透胁迫表型。在存在 ABA 的情况下，GLK1/2 调节几个 ABA 响应基因的全基因组 RNA 测序分析，包括 。染色质免疫沉淀和凝胶阻滞实验表明，GLK1/2 通过识别保守序列直接与 启动子结合。此外，GLK1/2 和 WRKY40 对 ABA 响应控制一组共同的下游靶基因的 RNA 测序分析表明，GLK1/2 和 WRKY40 对 ABA 响应控制一组共同的下游靶基因。此外，遗传相互作用测试的结果表明， 三重突变体表现出与 单突变体和 双突变体相似的 ABA 超敏性，而 （突变体）四重突变体表现出与 单突变体相似的 ABA 低敏性。基于这些结果，我们提出 GLK1/2-WRKY40 转录模块在 ABA 反应中起负调节作用。
