Xistは,X染色体不活性化センターの性質を持っています
L B Herzing1, J T Romer, J M Horn
1CRC Centre for Cell and Molecular Biology, Chester Beatty Laboratories, The Institute of Cancer Research, London, UK.
Nature
|March 20, 1997
まとめ
Xist遺伝子は,雌性哺乳類のX染色体不活性化に不可欠である. Xistを別の染色体に導入することで,cisの遺伝子を静止させる能力が示され,X-無活性化センターにおけるXistの役割が確認されました.
科学分野:
- 遺伝学 遺伝学とは
- エピジェネティクス エピジェネティクス
- 哺乳類の発達 哺乳類の発達
背景:
- X染色体不活性化により,哺乳類の性別間の遺伝子発現が均等になる.
- このプロセスは,女性の1つのX染色体を静止させ,X不活性化センター (Xic) から cis に作用します.
- Xicに位置するXist遺伝子は,不活性X染色体から発現し,核RNAを生成します.
研究 の 目的:
- Xist遺伝子がX染色体不活性化に十分であるかどうかを調査する.
- XistがX不活性化センターの特性を示すかどうかを判断する.
- X不活性化と染色体カウントにおけるオートソームXISTの役割を調査する.
主な方法:
- 胚性幹細胞のオートソームにXist遺伝子を導入する.
- Xist RNAの局所化を分析する.
- 固有のXist遺伝子発現とX染色体の不活性化に対する自己群 Xistの影響を観察した.
主要な成果:
- Xistは,オートソームに統合されると,cis.の遺伝子不活性化を誘導するのに十分でした.
- 統合遺伝子を含むオートソームの近くに位置するキストRNA.
- オートソーマルXistは,いくつかの細胞で内生Xistの活性化を誘発し,染色体カウントメカニズムへの関与を示唆しました.
結論:
- Xist遺伝子は,X無活性化センターの重要な特性を有しています.
- Xistは,X染色体の不活性化を開始するために必要なだけでなく,十分なものです.
- 発見は,哺乳類における用量補償の分子機構の洞察を提供します.
さらに関連する動画
12:42Quick Fluorescent In Situ Hybridization Protocol for Xist RNA Combined with Immunofluorescence of Histone Modification in X-chromosome Inactivation
Published on: November 26, 2014
08:27A Non-random Mouse Model for Pharmacological Reactivation of Mecp2 on the Inactive X Chromosome
Published on: May 22, 2019
関連する概念動画
X-Inactivation
The human X chromosome contains over ten times the number of genes as in the Y chromosome. Since males have only one X chromosome, and females have two, one might expect females to produce twice as many of the proteins, with undesirable results.
Inheritance 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...
Euchromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions take up more dye, appearing darker, while the less-compact areas take up less dye and appear lighter. Based on the compaction level, chromatins are classified into two primary forms – euchromatin and heterochromatin.
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
X-inactivation
The human X chromosome contains over ten times the number of genes as in the Y chromosome. Since males have only one X chromosome, and females have two, one might expect females to produce twice as many of the proteins, with undesirable results.
Heterochromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions that take up more dye are called heterochromatin. Heterochromatin is further classified into two forms – constitutive heterochromatin and facultative heterochromatin.
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
Heterochromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions that take up more dye are called heterochromatin. Heterochromatin is further classified into two forms – constitutive heterochromatin and facultative heterochromatin.
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
