Investigating the regulation of chromatin associated proteins by intrinsically disordered regions

在多细胞生物体中，每个细胞最初在其细胞核中都含有基因组的完整拷贝，但这些基因中只有一部分是活跃的并在使用中。对每个细胞中哪些基因开启、哪些基因关闭的适当调控，对于指导发育和所有基本身体功能至关重要。基因组不是以裸DNA的形式存在，而是被一种叫做组蛋白的蛋白质复合物包裹着，组蛋白与DNA一起形成了所谓的染色质。基因调控在很大程度上是由染色质如何包裹在单个基因周围决定的，而染色质又是由细胞核中各种大的蛋白质复合物控制的。这些蛋白复合物功能的一个关键方面是能够读取组蛋白上的翻译后修饰（PTMs）， PTMs作为标签引导它们到正确的位置。然而，在染色质的整体复杂性中，这些ptm如何促进这一过程仍然知之甚少。该项目解决了染色质背景下组蛋白PTM读数如何由这些染色质结合蛋白中的高度保守元件调节以控制发育过程中适当的基因转录的基本问题。除了科学目标之外，ppi还将与当地一所通勤学院密切合作，从代表性不足的群体中招募和留住年轻学生进入科学领域。他们还将通过参与科学艺术奖学金，鼓励在对话中使用艺术，从而加强科学界和非专业人士之间的交流。本项目中解决的问题对于理解组蛋白PTM读数在染色质背景下是如何调节的至关重要。具体来说，该项目将研究进化上保守的、内在无序的区域（IDRs）是如何调节核小体动力学、组蛋白PTM读取、转录和发育的。这一调控的机制基础将通过对保守的idrs -阅读器对的一系列核磁共振波谱实验来揭示。该项目将使用斑马鱼突变体的等位基因系列来测试这些idr在体内的功能重要性。选择性去除和替换这些深度保守的氨基酸残基，并与功能缺失的等位基因进行比较，将首次允许测试这些idr的发育和生理贡献。本项目由分子与细胞生物科学部分子生物物理和遗传机制组联合支持。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Each cell in a multi-cell organism originally contains a full copy of the genome in its nucleus, but only a subset of these genes is active and in use. Proper regulation of which genes are on, and which are off, in each cell is critical to steer development and all basic body functions. The genome does not exist as naked DNA but is wrapped around complexes of proteins called histones, which together with the DNA form so-called chromatin. Gene regulation is in large part dictated by how this chromatin is packaged around individual genes, which is in turn controlled by various large protein complexes in the nucleus. A critical aspect of these protein complexes’ function is the ability to read post-translational modifications (PTMs) on the histones, which act as labels to guide them to the correct place. However, how these PTMs contribute to this process is still poorly understood within the overall complexity of chromatin. This project addresses fundamental questions of how histone PTM readout in a chromatin context is regulated by highly conserved elements within these chromatin-binding proteins to control proper gene transcription during development. In addition to the scientific goals, the PIs will work closely with a local commuter college to recruit and retain young students from underrepresented groups into the sciences. They will also work to enhance communication between the scientific and lay communities by encouraging the use of art in this conversation, through participation in the Art of Science Fellowship. The questions addressed in this project are fundamentally important for understanding how histone PTM readout is regulated in the chromatin context. Specifically, this project will investigate how evolutionarily conserved, intrinsically disordered regions (IDRs) found adjacent to histone reader domains regulate nucleosome dynamics, histone PTM readout, transcription, and development. The mechanistic basis of this regulation will be uncovered using a series of NMR spectroscopy experiments on conserved IDRs-reader pairs. This project will test the functional importance of these IDRs in vivo using an allelic series of zebrafish mutants. Selective removal and substitution of these deeply conserved amino acid residues and comparison to loss-of-function alleles will allow, for the first time, testing of the developmental and physiological contribution of these IDRs. This project was supported jointly by Molecular Biophysics and Genetic Mechanism Clusters of the Division of Molecular and Cellular Biosciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.