Function of cohesin ring complexes in the control of phytohormone-mediated stress response andchromatin structuring in Arabidopsis

三维基因组结构对于基因表达的调控是决定性的。细胞学和生物化学研究，以及全基因组分析，已经确定了多种分子因子，如染色质绝缘体，多梳组复合物（PcG）和蛋白质环复合物，以构建染色质并调节真核生物中的基因转录-对生物体的发育和生理产生各种影响。对于植物，与其他真核生物如酵母和人类相比，我们对基因组结构形成的知识仍然是初步的，并且有很多证据表明植物在进化过程中已经发展了独特/额外的3D基因组包装分子机制。染色质结构是非常动态的，并根据细胞类型和细胞发育阶段而变化。特别是外部刺激引起的变化。在植物中，染色质重组响应非生物和生物胁迫，这显着有助于基因表达的适应。然而，染色质的三维结构是如何变化的，尤其是染色质环的景观，以及形成环的粘蛋白环复合物起什么作用还不清楚。敲除突变体的早期实验表明，某些粘着蛋白确实在拟南芥对外部刺激的反应中发挥了令人惊讶的作用。我打算调查的作用，三方的凝聚素环复合物的形成和调节的染色质环在营养植物细胞。在这里，我提出了一个假设，即粘附素环复合物是一个关键因素的可塑性和适应性的基因组通过控制染色质环的形成。它们可能负责基因簇的形成和分离、基因的沉默或增强子元件激活转录，这对于调节各种细胞过程非常重要，其中我对响应非生物和生物胁迫而发生的事件感兴趣。

The three-dimensional genome architecture is decisive for the regulation of gene expression. Cytological and biochemical studies, together with genome-wide analyses, have identified multiple molecular factors, such as chromatin insulators, Polycomb group complexes (PcG), and protein ring complexes to structure chromatin and regulate gene transcription in eukaryotes – with a variety of effects on the development and physiology of the organisms. For plants, compared to other eukaryotes such as yeasts and humans, our knowledge of the formation of genome structures is still rudimentary and there is much to suggest that plants, during evolution, have developed unique / additional molecular mechanisms of 3D genome packaging. The chromatin structure is very dynamic and changes according to cell types and cell developmental stages. Particularly strong is the change due to external stimuli. In plants, chromatin is reorganized in response to abiotic and biotic stress, which significantly contributes to the adaptation of gene expression. However, how the three-dimensional chromatin structure changes, especially the landscape of chromatin loops, and what role the loop-forming cohesin ring complexes play is not known yet. Early experiments with knockout mutants suggest that certain cohesins do indeed play a surprisingly strong role in responding to external stimuli in Arabidopsis. I intend to investigate the role of tripartite cohesin ring complexes in the formation and regulation of chromatin loops in vegetative plant cells. Here I put forward the hypothesis that cohesin ring complexes are a crucial factor for the plasticity and adaptability of the genome by controlling chromatin loop formation. They may be responsible for the formation and separation of gene clusters, the silencing of genes or the activation of transcription by enhancer elements, which is important to regulate all kinds of cellular processes, of which I am interested in the events that occur in response to abiotic and biotic stress in Arabidopsis.