Arabidopsis NF-YCs Mediate the Light-Controlled Hypocotyl Elongation via Modulating Histone Acetylation
Arabidopsis NF-YCs Mediate the Light-Controlled Hypocotyl Elongation via Modulating Histone Acetylation
复制标题
拟南芥 NF-YCs 通过调节组蛋白乙酰化介导光控下胚轴伸长
DOI：
10.1016/j.molp.2016.11.007
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发表时间：
2017-02-13
期刊：
影响因子：
27.5
通讯作者：
Hou, Xingliang
中科院分区：
文献类型：
--
作者：
Tang, Yang;Liu, Xuncheng;Hou, Xingliang
光是促进光形态发生的关键环境信号，这是植物适应各种外部挑战的一系列依赖光的变化的发育过程。染色质修饰被认为参与了这种光介导的生长，但其潜在的机制仍然是难以捉摸的。在这项研究中，我们鉴定了四种拟南芥核因子- yc同源物，NF-YC1, NF-YC3， NF-YC4和NF-YC9 (NF-YCs)，它们通过组蛋白去乙酰化作为光控下胚轴伸长的冗余抑制因子。在光照条件下生长的NF-YCs功能丧失突变体幼苗中观察到明显的黄化表型，包括显著延长的下胚轴和较少开放的子叶。我们发现NF-YCs在光照下与组蛋白去乙酰化酶HDA15相互作用，共同靶向一组下胚轴延长相关基因的启动子，调节相关染色质上组蛋白H4乙酰化水平，从而抑制基因表达。相反，NF-YC-HDA15复合物在黑暗中被靶基因排除，导致H4乙酰化水平升高，从而导致黄化生长。进一步分析表明，NF-YCs对光控下胚轴伸长的转录抑制活性部分取决于HDA15的去乙酰化活性，HDA15功能的丧失可以挽救NF-YCs过表达植株的短下胚轴表型。综上所述，我们的研究结果表明，NF-YC1、NF-YC3、NF-YC4和NF-YC9作为转录共抑制因子，通过与HDA15相互作用抑制幼苗早期光形态发生过程中的下胚轴伸长。我们的研究结果强调，NF-YCs可以通过表观遗传调控来调节植物的发育，以响应环境线索。
Light is a crucial environmental signal that promotes photomorphogenesis, the developmental process with a series of light-dependent alterations for plants to adapt various external challenges. Chromatin modification has been proposed to be involved in such light-mediated growth, but the underlying mechanism is still elusive. In this study, we identified four Arabidopsis thaliana Nuclear Factor-YC homologs, NF-YC1, NF-YC3, NF-YC4, and NF-YC9 (NF-YCs), which function redundantly as repressors of light-controlled hypocotyl elongation via histone deacetylation. Obvious etiolation phenotypes are observed in NF-YCs loss-of-function mutant seedlings grown under light conditions, including significant elongated hypocotyls and fewer opened cotyledons. We found that NF-YCs interact with histone deacetylase HDA15 in the light, co-target the promoters of a set of hypocotyl elongation-related genes, and modulate the levels of histone H4 acetylation on the associated chromatins, thus repressing gene expression. In contrast, NF-YC-HDA15 complex is dismissed from the target genes in the dark, resulting in increased level of H4 acetylation and consequent etiolated growth. Further analyses revealed that transcriptional repression activity of NF-YCs on the light-controlled hypocotyl elongation partially depends on the deacetylation activity of HDA15, and loss of HDA15 function could rescue the short-hypocotyl phenotype of NF-YCs overexpression plants. Taken together, our results indicate that NF-YC1, NF-YC3, NF-YC4, and NF-YC9 function as transcriptional co-repressors by interacting with HDA15 to inhibit hypocotyl elongation in photomorphogenesis during the early seedling stage. Our findings highlight that NF-YCs can modulate plant development in response to environmental cues via epigenetic regulation.