新しいエピジェネティック効果は,分裂酵母におけるセントロメア機能を変化させることができる
1Department of Biological Sciences, University of California, Santa Barbara 93106.
Cell
|December 2, 1994
まとめ
科学者たちは,S. pombeで非機能的セントロメアを活性化する新しい表遺伝的メカニズムを発見しました. このエピジェネティックシステムは,DNAを変更することなく,不活性なセントロメアを活性化させ,セントロメア形成のための新しい測定法を提供します.
科学分野:
- エピジェネティクス エピジェネティクス
- 分子生物学は分子生物学である.
- クロマチンの生物学
背景:
- セントロメアは,細胞分裂中の染色体分離に不可欠です.
- S. pombe のミニクロモソームは,セントロメア機能を研究するためのモデルシステムを提供します.
- エピジェネティック調節は,遺伝子発現とゲノム安定性において重要な役割を果たします.
研究 の 目的:
- 生命体内でセンターメア機能を調節する新しい表遺伝的メカニズムを特定する.
- 非機能的セントロメアを機能的セントロメアに変換することを研究する.
- セントロメア活動におけるクロマチンの構造の役割を調査する.
主な方法:
- S. pombeをモデル生物として利用しました.
- ミニクロモソームを研究し,簡略化されたセントロメリックDNA構造を研究した.
- ミトスの細胞分裂中に観察されたセントロメア活動.
- エピジェネティック変異とクロマチンの構造を分析した.
主要な成果:
- 非機能的セントロメアを活性化する新しい表遺伝的メカニズムを特定しました.
- DNAの含有量または改変の変更なしに,セントロメア変換が実証されています.
- ミトーシス中の高周波変換が観察され,インビボ測定法を提供した.
- セントロメリック成分を高階クロマチンの構造にデノボ折りたたむモデルをサポートしました.
結論:
- S. pombe の新しい表遺伝系は,センターメアの機能を調節する.
- このシステムは,クロマチンの改造によって,不活性なセントロメアを活性状態に変換することができます.
- この発見は,セントロメア形成と表遺伝子遺伝に関する洞察を提供している.
関連する概念動画
02:30Histone Variants at the Centromere
Histone variants are the histone proteins with structural and sequence variations. These variants may be regarded as “mutant” forms that replace their canonical histone counterparts in the nucleosomes. Specific post-translational modifications on the histone variants enable further chromatin complexity and regulate tissue-specific gene expression. The most common histone variants are from histone H2A, H2B, and linker histone H1 families. However, several variants of histone H3 variants are also...
03:17Inheritance of Chromatin Structures
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 DNA...
02:25Centrosome Duplication
The primary microtubule organizing center (MTOC) in animal cells is the centrosome. A centrosome has two cylindrical centrioles at its core. Each centriole consists of nine sets of three microtubules held together by proteins. The centrioles are positioned at right angles to each other and surrounded by a shapeless protein cloud called the pericentriolar matrix, or pericentriolar material (PCM).
To ensure that each daughter cell receives a centrosome after cell division, centrosome duplication...
To ensure that each daughter cell receives a centrosome after cell division, centrosome duplication...
01:37Epigenetic Regulation
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...
02:25Centrosome Duplication
The primary microtubule organizing center (MTOC) in animal cells is the centrosome. A centrosome has two cylindrical centrioles at its core. Each centriole consists of nine sets of three microtubules held together by proteins. The centrioles are positioned at right angles to each other and surrounded by a shapeless protein cloud called the pericentriolar matrix, or pericentriolar material (PCM).
To ensure that each daughter cell receives a centrosome after cell division, centrosome duplication...
To ensure that each daughter cell receives a centrosome after cell division, centrosome duplication...
01:24Methods of Nuclear Reprogramming
Nuclear reprogramming is a process of transforming one cell type into an unrelated cell type by epigenetic changes that alter the cell’s original gene expression pattern. Such epigenetic changes force cells to express a different set of genes, which play a significant role in inducing transformation into other cell types. Nuclear reprogramming offers applications in reproductive cloning for livestock propagation and regenerative medicine — developing patient-specific cells for injury repair.