Regulation of cell reprogramming by matrix stiffness

通过基质硬度调节细胞重编程

• 批准号: 10281141
• 负责人: Song Li
• 金额: $ 32.48万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-20 至 2025-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10281141
• 关键词: Actins; Biocompatible Materials; Biological; Biology; Biophysical Process; Biophysics; Cardiac Myocytes; Cell Nucleus; Cell physiology; Cells; Cues; Cytoskeleton; Data; Development; Disease model; Distant; Drug Screening; Epigenetic Process; Extracellular Matrix; F-Actin; Fibroblasts; Focal Adhesions; G Actin; Gene Expression; Gene Targeting; Genes; Genomics; Histone Acetylation; Mediating; Microfilaments; Modification; Neurons; Nuclear; Nuclear Translocation; Phenotype; Play; Process; Regenerative Medicine; Regulation; Role; Site; Somatic Cell; Surface; Testing; Tissue Engineering; Transgenes; Work; base; cell type; cellular engineering; cofilin; depolymerization; design; drug discovery; epigenomics; experience; histone acetyltransferase; induced pluripotent stem cell; live cell imaging; migration; multidisciplinary; novel; novel strategies; nucleocytoplasmic transport; transcription factor; transcriptomics; Actins; Biocompatible Materials; Biological; Biology; Biophysical Process; Biophysics; Cardiac Myocytes; Cell Nucleus; Cell physiology; Cells; Cues; Cytoskeleton; Data; Development; Disease model; Distant; Drug Screening; Epigenetic Process; Extracellular Matrix; F-Actin; Fibroblasts; Focal Adhesions; G Actin; Gene Expression; Gene Targeting; Genes; Genomics; Histone Acetylation; Mediating; Microfilaments; Modification; Neurons; Nuclear; Nuclear Translocation; Phenotype; Play; Process; Regenerative Medicine; Regulation; Role; Site; Somatic Cell; Surface; Testing; Tissue Engineering; Transgenes; Work; base; cell type; cellular engineering; cofilin; depolymerization; design; drug discovery; epigenomics; experience; histone acetyltransferase; induced pluripotent stem cell; live cell imaging; migration; multidisciplinary; novel; novel strategies; nucleocytoplasmic transport; transcription factor; transcriptomics

Project Summary Cell reprogramming represents a major advancement in biology, and has wide applications in regenerative medicine, disease modeling and drug screening. During cell reprogramming, cells experience epigenetic changes that result in a cell phenotype switch. However, whether and how biophysical factors regulate cell reprogramming through epigenetic modifications are not well understood. We have found that biophysical factors, specifically extracellular matrix (ECM) stiffness, has profound effects on epigenetic state and the conversion of fibroblasts into induced neuronal (iN) cells, with the highest efficiency at an intermediate ECM stiffness, which is regulated by focal adhesions and the cytoskeleton. In addition, we have discovered that actin assembly and transport into nucleus plays an important role in epigenetic modulation. Based on our preliminary data, we hypothesize that (1) biophysical cues such as ECM stiffness regulates FAs, actin assembly/disassembly, nuclear transport of actin, and thus, HAT activity to modulate the epigenetic state and cell reprogramming process and (2) an intermediate level of stiffness is optimal for epigenetic remodeling and cell reprogramming. To test our hypothesis, we propose three Specific Aims: (1) Investigate how matrix stiffness regulates iN reprogramming through FAs and actin cytoskeleton, (2) Elucidate how matrix stiffness modulates HAT and the epigenetic state to turn on neuronal genes during iN reprogramming, and (3) Determine the role of actin nuclear transport in matrix stiffness- modulation of HAT and epigenetic state during iN reprogramming. We have assembled a multidisciplinary team with expertise on mechanobiology, cell engineering, high throughput genomic and epigenomic analysis, and live cell imaging to work together and investigate the underlying biophysical and biological mechanisms. Our proposed studies will be one of the first to elucidate how ECM stiffness regulates transcriptomic and epigenetic changes for cell reprogramming, and how ECM stiffness modulates focal adhesions and the cytoskeleton for cell reprogramming. Findings from this project will unravel new mechanisms of cell fate determination, which will have wide applications in cell and tissue engineering, disease modeling and drug discovery, and provide a rational basis for the optimization and development of novel biomaterials for somatic cell reprogramming.

项目摘要 细胞重编程代表生物学的重大进步，并且在 再生医学，疾病建模和药物筛查。在细胞重编程过程中，细胞经历 表观遗传变化导致细胞表型开关。但是，是否以及生物物理因素如何 通过表观遗传修饰调节细胞重编程尚不清楚。我们发现 生物物理因子，特别是细胞外基质（ECM）刚度，对表观遗传学有深远的影响 状态和成纤维细胞转化为诱导的神经元（IN）细胞，在 中间ECM刚度，受焦点粘连和细胞骨架调节。另外，我们 已经发现肌动蛋白组装和运输到核中在表观遗传学中起重要作用 调制。根据我们的初步数据，我们假设（1）生物物理提示，例如ECM 刚度调节FAS，肌动蛋白组装/拆卸，肌动蛋白的核运输，从而使HAT活动到 调节表观遗传状态和细胞重编程过程，（2）中间刚度是 最佳表观遗传重塑和细胞重编程。为了检验我们的假设，我们提出了三个 具体目的：（1）研究矩阵刚度如何通过FAS和肌动蛋白进行重编程时如何调节 细胞骨架，（2）阐明矩阵刚度如何调节帽子和表观遗传状态以打开神经元 在重编程过程中基因，（3）确定肌动蛋白核转运在基质刚度中的作用 在重编程过程中调节帽子和表观遗传状态。我们已经组装了一个多学科 团队具有机械生物学，细胞工程，高通量基因组和表观基因组的专业知识 分析和活细胞成像一起工作并研究潜在的生物物理和生物学 机制。我们提出的研究将是最早阐明ECM刚度调节的研究之一 转录组和表观遗传学的变化用于细胞重编程，以及ECM刚度如何调节局灶性 粘连和细胞骨骼重编程。该项目的发现将揭示新的 细胞命运确定的机制，该机制将在细胞和组织工程中广泛应用， 疾病建模和药物发现，并为优化和发展提供合理的基础 用于体细胞重编程的新型生物材料。