Understanding the role of tether proteins to maintain chromatin-nuclear lamina contacts in premature aging.

了解系链蛋白在过早衰老过程中维持染色质-核层接触的作用。

基本信息

批准号：
10647365
负责人：
Andrey Poleshko
金额：
$ 24.38万
依托单位：
UNIVERSITY OF PENNSYLVANIA
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-05-15 至 2025-02-28
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10647365
关键词：
Adopted Affect Binding Biological Assay Cell Nucleus Cells Chromatin DNA Sequence Alteration Data Defect Development Disease Epigenetic Process Farnesyl Transferase Inhibitor Gene Silencing Genetic Transcription Genome Genomic approach Goals Heart failure Heterochromatin Histone H3 Interruption Investigation Knowledge Lamin Type A Link Maintenance Maps Methylation Modification Molecular Morphology Mutation Nuclear Nuclear Lamin Nuclear Lamina Pathway interactions Peripheral Play Positioning Attribute Premature aging syndrome Process Progeria Protein Isoforms Proteins Regulation Role Site Structure Surface Syndrome Testing Work domain mapping epigenetic regulation experimental study genome-wide heterochromatin-specific nonhistone chromosomal protein HP-1 histone modification imaging approach insight knock-down mutant overexpression population based proline-rich proteins transcriptome sequencing tumorigenesis

项目摘要

Project Summary/Abstract This proposal outlines an investigation into the role of chromatin-tethering proteins in maintenance of peripheral heterochromatin and the integrity of nuclear lamina. It is well established that heterochromatin association with the nuclear lamina plays an important role in development, and contributes to maintenance of the adopted cell fate. Genetic mutations in lamina proteins, such as is seen in Hutchinson-Gilford progeria syndrome (HGPS), is associated with alterations in the morphology of the nuclear lamina and disruption of peripheral heterochromatin. However, the precise link between nuclear lamina mutations and heterochromatin positioning remains unclear. I propose to test if the chromatin-tethering protein PRR14 plays a critical role in this process and therefore functions in the premature aging pathway. Our data demonstrate that PRR14 organizes a significant fraction of heterochromatin at the nuclear lamina. Lack of PRR14 results in detachment of the peripheral heterochromatin from the nuclear lamina, while PRR14 overexpression substantially increases the fraction of heterochromatin located at the nuclear periphery. Previous findings implicate PRR14 as an epigenetic repressor and its loss can release transcriptional gene silencing. Furthermore, our results demonstrate that PRR14 loss results in nuclear lamina defects similar to those observed in diseases associated with nuclear lamina mutations. Here we propose to study the role of PRR14 in maintenance of chromatin organization at the nuclear lamina and assess how nuclear lamina mutations act through PRR14 to cause dysregulation of lamina-associated chromatin. We will determine the effect of PRR14 loss on heterochromatin organization at the nuclear lamina and define epigenetic features that mark genome regions for nuclear lamina localization via PRR14. Further, we will determine how nuclear lamina mutations affect the PRR14 function in organizing chromatin at the nuclear lamina by testing how Progerin (a mutant form of Lamin A protein) affects the PRR14-nuclear lamina interaction and triggers nuclear lamina and peripheral heterochromatin defects. Finally, to determine if PRR14-nuclear lamina association is affected by farnesyl group modification on Progerin, we will test whether farnesyltransferase inhibitors restore PRR14 function in tethering heterochromatin in HGPS cells. Our work will provide critical insights into the fundamental knowledge of chromatin association with the nuclear lamina. This would significantly advance our understanding of molecular mechanism behind nuclear lamina and genome organization defects observed in laminopathy diseases.

项目概要/摘要该提案概述了对染色质束缚蛋白在维持外周细胞中的作用的研究。异染色质和核纤层的完整性。众所周知，异染色质与核层在发育中起着重要作用，并有助于维持所采用的细胞命运。核纤层蛋白的基因突变，如哈钦森-吉尔福德早衰综合症 (HGPS) 中所见，是与核纤层形态的改变和外周异染色质的破坏有关。然而，核纤层突变和异染色质定位之间的确切联系仍不清楚。我建议测试染色质束缚蛋白 PRR14 是否在此过程中发挥关键作用，因此在过早衰老途径中发挥作用。我们的数据表明 PRR14 组织了很大一部分核层上的异染色质。 PRR14 缺乏导致外周异染色质脱离来自核纤层，而 PRR14 过表达显着增加了异染色质的比例位于核外围。先前的研究结果表明 PRR14 是一种表观遗传抑制因子，其缺失可能会导致释放转录基因沉默。此外，我们的结果表明 PRR14 丢失会导致核核纤层缺陷类似于在与核纤层突变相关的疾病中观察到的缺陷。在这里我们建议研究 PRR14 在维持核层染色质组织中的作用并评估其作用核纤层突变通过 PRR14 起作用，导致核纤层相关染色质失调。我们将确定 PRR14 丢失对核层异染色质组织的影响并定义表观遗传通过 PRR14 标记基因组区域以进行核纤层定位的特征。此外，我们将确定如何通过测试核纤层突变如何影响 PRR14 在核纤层染色质组织中的功能 Progerin（Lamin A 蛋白的一种突变形式）影响 PRR14-核纤层相互作用并触发核椎板和周围异染色质缺陷。最后，确定 PRR14-核层关联是否 Progerin受到法尼基修饰的影响，我们将测试法尼基转移酶抑制剂是否恢复 PRR14 在 HGPS 细胞中束缚异染色质中发挥作用。我们的工作将为以下方面提供重要见解：染色质与核层关联的基础知识。这将显着推进我们的了解核纤层背后的分子机制和观察到的基因组组织缺陷核纤层病疾病。