マウスにおけるアンドロゲネティック・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・
Nature
|March 1, 1987
まとめ
母親と父親のゲノムは,マウス胚の発達に不可欠です. 化学胚は細胞の空間的分離を示しますが,完全な発達には,同じ細胞内の両方の親遺伝子が必要です.
科学分野:
- 発達生物学 発達生物学について
- ゲノミクスゲノミクスとは
- エピジェネティクス エピジェネティクス
背景:
- マウスの適切な胚発達には,母子のゲノムと父子のゲノムの両方が必要です.
- アンドロゲネティックおよびパートノゲネティック胚は,相補的なゲノム情報を強調する,明確な現象型を示します.
- アンドロゲネティック細胞とパートノゲネティック細胞を組み合わせたキメラは,親のゲノム機能を研究するためのモデルを提供します.
研究 の 目的:
- マウス・キメラのアンドロゲネティック・細胞とパートノゲネティック・細胞を組み合わせることで生じる機能的影響を調査する.
- 異なる親の起源の細胞の空間的分布と発達への貢献を決定する.
- 完全な胚の発達のために,同局的親遺伝子の必要性を理解する.
主な方法:
- アンドロゲネティック・パルテノゲネティック・キメリック・マウス胚の構築.
- 胚組織,トロフォブラスト,卵黄袋内の細胞分布の分析.
- キメリック胎児の発達進捗と生存能力の評価.
主要な成果:
- パルテノジェネティック細胞は,主に胚自体で見つかりました.
- アンドロゲネティック細胞は主にトロフォブラストを形成した.
- 卵黄の袋には,両方の細胞の混合物が含まれていた.
- キメリック胎児は,不完全な機能的補完を示し,期限まで発達しなかった.
結論:
- キメラの親遺伝子の発現は,細胞系統の空間的分離につながります.
- 期限に達しなかったことは,同じ細胞内の両方の親遺伝子の共同局所化は,マウスの完全な発達に不可欠であることを示唆しています.
- ゲノムインプリントを超えた発達制御は,個々の細胞における両方の染色体組の存在に依存する可能性があります.
関連する概念動画
01:58X-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.
01:39Chromosomal Theory of Inheritance
In 1866, Gregor Mendel published the results of his pea plant breeding experiments, providing evidence for predictable patterns in the inheritance of physical characteristics. The significance of his findings was not immediately recognized. In fact, the existence of genes was unknown at the time. Mendel referred to hereditary units as “factors.”
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...
02:27Background and Environment Affect Phenotype
Although the genetic makeup of an organism plays a major role in determining the phenotype, there are also several environmental factors, such as temperature, oxygen availability, presence of mutagens, that can alter an organism’s phenotype.
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
02:19The Y Chromosome Determines Maleness
The Y chromosome is a sex chromosome found in several vertebrates and mammals, including humans. In addition to 22 pairs of autosomes, the human males have one X chromosome and one Y chromosome. In these organisms, the presence or absence of the Y chromosome determines the development of male traits.
Evolution
Around 300 million years ago, the two sex chromosomes diverged from two identical autosomal chromosomes. Over time, the Y chromosome has lost most of its genes, shrinking in size. Today,...
Evolution
Around 300 million years ago, the two sex chromosomes diverged from two identical autosomal chromosomes. Over time, the Y chromosome has lost most of its genes, shrinking in size. Today,...
02:45The Ratio of X Chromosome to Autosomes
In most organisms, sex is determined by the ratio of X and Y chromosomes. However, in some organisms, such as Drosophila and C.elegans, sex is determined by the ratio of the number of X chromosomes to the number of sets of autosomes. The Y chromosome in Drosophila is active but does not determine sex. It contains genes responsible for the production of sperms in adult flies.
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...