全ゲノム倍増は,腫瘍性クロマチン分離の損失を誘発する
Ruxandra A Lambuta1,2, Luca Nanni2,3,4, Yuanlong Liu2,3,4
1Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, EPFL, Écublens, Switzerland.
Nature
|March 16, 2023
まとめ
全ゲノム倍化 (WGD) は,p53欠乏した癌細胞におけるクロマチンの分離 (LCS) の喪失を引き起こします. この染色体の再編成は表遺伝的変化によって引き起こされ,腫瘍遺伝子の活性化と腫瘍の進行を促進し,WGDによって引き起こされるがんにおける染色体の進化を強調する.
科学分野:
- 癌 生物学
- ゲノミクス
- エピジェネティクス
背景:
- 全ゲノム倍化 (WGD) はヒトの癌において一般的であり,染色体不安定性とアヌプロイドを促進する.
- WGDがクロマチンの3D組織に与える影響と,がんの表型におけるその役割は,ほとんど不明である.
研究 の 目的:
- WGD癌細胞の3次元クロマチン組織を調査する
- WGDによるクロマチンの変化が腫瘍性フェノタイプに与える影響を決定する.
主な方法:
- 全ゲノム倍増後のp53欠乏細胞の分析
- クロマチンの組織変化を追跡するための縦断的な研究
- クロマチン分離におけるCTCFとH3K9me3の役割を評価する.
主要な成果:
- WGDは,p53欠乏細胞における染色体分離の損失 (LCS) を誘導し,染色体サイズとサブコンパートメントの分離が減少することが特徴です.
- LCSは,テトラプロイドチェックポイントをバイパスする細胞におけるCTCFとH3K9me3のレベル低下によって引き起こされます.
- LCSはサブコンパートメントの再定位を促し,腫瘍遺伝子を活性化する表遺伝的および転写的変化をもたらします.
結論:
- 染色体分離の喪失は,がんにおけるWGDの早期の結果である.
- 染色体の変化とは無関係な染色体の再編成は,腫瘍の発達を誘発する遺伝的変化を補完します.
- 染色体の進化はWGDによって引き起こされる癌の重要な特徴であり,腫瘍遺伝子の活性化と進行に影響を与えます.
関連する概念動画
Duplication of Chromatin Structure
5.6K
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...
5.6K
Gene Conversion
9.8K
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
9.8K
Fixing Double-strand Breaks
12.7K
The double-stranded structure of DNA has two major advantages. First, it serves as a safe repository of genetic information where one strand serves as the back-up in case the other strand is damaged. Second, the double-helical structure can be wrapped around proteins called histones to form nucleosomes, which can then be tightly wound to form chromosomes. This way, DNA chains up to 2 inches long can be contained within microscopic structures in a cell. A double-stranded break not only damages...
12.7K
Loss of Tumor Suppressor Gene Functions
5.0K
Tumor suppressor genes are normal genes that can slow down cell division, repair DNA mistakes, or program the cells for apoptosis in case of irreparable damage. Hence, they play an essential role in preventing the proliferation of damaged cells.
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...
5.0K
Inheritance of Chromatin Structures
6.3K
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...
6.3K
Epigenetic Regulation
3.1K
Epigenetic changes alter the physical structure of the DNA without changing the genetic sequence and often regulate whether genes are turned on or off. This regulation ensures that each cell produces only proteins necessary for its function. For example, proteins that promote bone growth are not produced in muscle cells. Epigenetic mechanisms play an essential role in healthy development. Conversely, precisely regulated epigenetic mechanisms are disrupted in diseases like cancer.
X-chromosome...
X-chromosome...
3.1K


