在C9orf72中重复扩展重新连接ALS中的3D染色质景观
bioRxiv : the preprint server for biology
|February 23, 2026
概括
在C9orf72中GGGGCC短串重复扩张会在肌缩侧面硬化症 (ALS) 中引起神经退行. 这项研究揭示了这些扩张通过创建新的染色质循环来破坏神经元基因组结构,从而导致基因失调.
科学领域:
- 神经科学是一个神经科学.
- 基因组学就是基因组学.
- 分子生物学分子生物学
背景情况:
- 肌缩侧面硬化 (ALS) 是一种神经退行性疾病,通常是由C9orf72基因中的GGGGCC短串重复 (STR) 扩张引起的.
- 将C9orf72-STR扩张与神经退行症联系在一起的确切机制尚未完全理解.
研究的目的:
- 研究一种涉及C9orf72-STR扩张驱动ALS中高阶染色体结构的新型机制.
- 了解C9orf72-STR扩张如何导致转录基因失调和神经退行.
主要方法:
- 染色体构造捕获技术用于分析全基因组的染色体循环.
- 通过RNA结合蛋白免疫沉 (RIP) 来识别RNA-DNA相互作用.
- 转录组分析以评估基因表达变化.
主要成果:
- C9orf72-STR扩张诱导在染色质环中的广泛,神经元特异性增长.
- 这些异常循环与C9orf72-STRRNA结合点和CTCF结合.
- 宫外环的形成与ALS中显著的转录基因失调有关.
结论:
- C9orf72-STR扩张通过促进RNA驱动的异常色素环形成来重塑神经元基因组.
- 这种改变的核拓扰乱了基因表达,为C9-ALS的神经退行提供了机制.
- 这些发现突出了RNA-DNA相互作用在基因组组织和疾病发病过程中的作用.
相关概念视频
Chromatin Position Affects Gene Expression
25.0K
Chromatin is the massive complex of DNA and proteins packaged inside the nucleus. The complexity of chromatin folding and how it is packaged inside the nucleus greatly influences access to genetic information. Generally, the nucleus' periphery is considered transcriptionally repressive, while the cell's interior is considered a transcriptionally active area.
Topologically Associated Domains (TADs)
The 3-dimensional positioning of chromatin in the nucleus influences the...
Topologically Associated Domains (TADs)
The 3-dimensional positioning of chromatin in the nucleus influences the...
25.0K
Duplication of Chromatin Structure
7.4K
The process of chromosome duplication during cell division requires genome-wide disruption and re-assembly of chromatin. The chromatin structure must be accurately inherited, reassembled, and maintained in the daughter cells to ensure lineage propagation.
The basic unit of the chromatin is the nucleosome, consisting of DNA wrapped around octameric histone proteins and short stretches of linker DNA separating individual nucleosomes. The histone proteins within the nucleosome have their...
The basic unit of the chromatin is the nucleosome, consisting of DNA wrapped around octameric histone proteins and short stretches of linker DNA separating individual nucleosomes. The histone proteins within the nucleosome have their...
7.4K
Inheritance of Chromatin Structures
7.7K
Epigenetics is the study of inherited changes in a cell's phenotype without changing the DNA sequences. It provides a form of memory for the differential gene expression pattern to maintain cell lineage, position-effect variegation, dosage compensation, and maintenance of chromatin structures such as telomeres and centromeres. For example, the structure and location of the centromere on chromosomes are epigenetically inherited. Its functionality is not dictated or ensured by the underlying...
7.7K
Spreading of Chromatin Modifications
9.7K
The histone proteins in the nucleosomes are post-translationally modified (PTM) to increase or decrease access to DNA. The commonly observed PTMs are methylation, acetylation, phosphorylation, and ubiquitination of lysine amino acids in the histone H3 tail region. These histone modifications have specific meaning for the cell. Hence, they are called "histone code". The protein complex involved in histone modification is termed as "reader-writer" complex.
Writers
The writer...
Writers
The writer...
9.7K
Chromatin Modification in iPS Cells
2.2K
Chromatin modification alters gene expression; therefore, scientists can add histone-modifying enzymes, histone variants, and chromatin remodeling complexes to somatic cells to aid reprogramming into pluripotent stem (iPS) cells.
Compact chromatin makes reprogramming difficult. Enzymes, such as histone demethylases and acetyltransferases, are often added during reprogramming to loosen the chromatin, making the DNA more accessible to transcription factors. Molecules that inhibit histone...
Compact chromatin makes reprogramming difficult. Enzymes, such as histone demethylases and acetyltransferases, are often added during reprogramming to loosen the chromatin, making the DNA more accessible to transcription factors. Molecules that inhibit histone...
2.2K
Nucleosome Remodeling
11.4K
Nucleosomes are the basic units of chromatin compaction. Each nucleosome consists of the DNA bound tightly around a histone core, which makes the DNA inaccessible to DNA binding proteins such as DNA polymerase and RNA polymerase. Hence, the fundamental problem is to ensure access to DNA when appropriate, despite the compact and protective chromatin structure.
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
11.4K


