Investigation of a potential function of COR27 and COR28 in phytochrome-mediated chromatin remodelling

COR27 和 COR28 在光敏色素介导的染色质重塑中潜在功能的研究

• 批准号: 515270717
• 负责人: Professor Dr. Andreas Hiltbrunner
• 金额: --
• 依托单位: Institute of Plant Biology
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/515270717?language=en
• 关键词: Investigation; potential; function; COR27; COR28

Light is one of the most important environmental factors controlling almost all aspect of plant growth and development. Plants possess a plethora of proteins involved in light perception and light signal transduction to sense and adapt to the light conditions in their environment. In addition, many factors involved in light signalling also have a function in crosstalk between different signalling pathways to integrate internal and external stimuli. Light signalling in plants begins with the perception of light quality and quantity by photoreceptors. Among them, phytochromes (phys) are mainly responsible for red- and far- red light-dependent responses. With COLD REGULATED GENE 27 (COR27), and its homologue COR28, we have identified two proteins that interact directly with phyA and phyB and play a role in light-dependent hypocotyl growth, induction of flowering, regulation of circadian rhythms, and freezing tolerance. Thus, they are likely involved in the integration of light and temperature signals. The cor27-2 cor28-2 double mutant is hypersensitive to red light in a phyB-dependent manner and flowers late under long-day conditions, while seedlings overexpressing COR27 or COR28 are hyposensitive to red light. Furthermore, we have shown that COR27 and COR28 are targets of the CONSTITUTIVELY PHOTOMORPHOGENIC 1/SUPPRESSOR OF phyA-105 (COP1/SPA) E3 ubiquitin ligase complex and stabilised by light, probably through photoreceptor-dependent inactivation of COP1/SPA. Recently, COR27 and COR28 were shown to bind to ELONGATED HYPOCOTYL 5 (HY5), a central transcription factor involved in light signalling, thereby repressing the transcriptional activity of HY5. However, RNAseq data and phenotypic analysis revealed that the effect of COR27 and COR28 on seedling development is largely independent of HY5. Therefore, the main pathways of COR27 and COR28 action remain elusive. In the proposed project, we plan to investigate the relevance of the direct association of COR27 and COR28 with phyA and phyB, and examine potential COR27/COR28 interaction partners that we recently identified by AP-MS and that point to a role of COR27 and COR28 in chromatin remodelling. Consequently, we aim to analyse whether COR27 and COR28 affect chromatin density and histone modifications, and we want to identify direct target genes of COR27 and COR28 using a ChIP-seq approach. Overall, the aim of the proposed project is to understand how phytochromes, COR27 and COR28, and factors involved in regulation of chromatin density and histone modifications act together to control light-regulated gene expression.

光是控制植物生长和发育的几乎所有方面的最重要的环境因素之一。植物拥有大量参与光感知和光信号转导的蛋白质，以感知和适应环境中的光条件。此外，参与光信号传递的许多因素也具有不同信号通路之间串扰的功能，以整合内部和外部刺激。植物中的光信号始于光感受器对光质量和光量的感知。其中，光敏色素（phys）主要负责红光和远红光依赖性反应。通过冷调节基因 27 (COR27) 及其同源物 COR28，我们鉴定了两种直接与 phyA 和 phyB 相互作用的蛋白质，并在光依赖性下胚轴生长、诱导开花、调节昼夜节律和耐冻性中发挥作用。因此，它们可能参与光和温度信号的整合。 cor27-2 cor28-2双突变体以phyB依赖性方式对红光过敏，并且在长日照条件下开花较晚，而过表达COR27或COR28的幼苗对红光不敏感。此外，我们还表明，COR27 和 COR28 是组成性光形态 1/phyA-105 抑制剂 (COP1/SPA) E3 泛素连接酶复合物的靶标，并可能通过光感受器依赖性 COP1/SPA 失活而被光稳定。最近，COR27 和 COR28 被证明可以与伸长下胚轴 5 (HY5)（一种参与光信号传导的中央转录因子）结合，从而抑制 HY5 的转录活性。然而，RNAseq数据和表型分析表明COR27和COR28对幼苗发育的影响很大程度上独立于HY5。因此，COR27 和 COR28 作用的主要途径仍然难以捉摸。在拟议的项目中，我们计划调查 COR27 和 COR28 与 phyA 和 phyB 直接关联的相关性，并检查我们最近通过 AP-MS 识别的潜在 COR27/COR28 相互作用伙伴，这些伙伴指出了 COR27 和 COR28 的作用在染色质重塑中。因此，我们的目标是分析 COR27 和 COR28 是否影响染色质密度和组蛋白修饰，并且我们希望使用 ChIP-seq 方法鉴定 COR27 和 COR28 的直接靶基因。总体而言，该项目的目的是了解光敏色素、COR27 和 COR28 以及参与染色质密度调节和组蛋白修饰的因子如何共同作用来控制光调节基因表达。