哺乳动物卵细胞中染色体组质子的与衰老相关的减少
Masashi Mori1, Manami Koshiguchi1, Osamu Takenouchi1
1Laboratory for Chromosome Segregation, RIKEN Center for Biosystems Dynamics Research (BDR), Kobe, Japan.
概括
衰老的哺乳动物卵细胞显示染色体基因组的减少,影响基因表达,但不会导致介质性错误. 这项研究研究了卵细胞衰老期间的组质子变化及其对染色体分离的影响.
科学领域:
- 生殖生物学 生殖生物学
- 分子遗传学 分子遗传学
- 细胞生物学 细胞生物学
背景情况:
- 哺乳动物卵细胞在化过程中长时间停滞,这对随着年龄的增长而维持染色体蛋白质带来了挑战.
- 卵细胞衰老与染色体分离中的潜在错误有关,这对繁殖成功至关重要.
研究的目的:
- 为了研究衰老对哺乳动物卵细胞染色体组素水平的影响.
- 为了确定与年龄相关的组素减少和转录基因变化之间的关系.
- 评估降低的质子水平是否有助于衰老卵细胞中介质分离错误.
主要方法:
- 在不同年龄的卵细胞中,测量基因组变体 (H3.1/H3.2和H3.3) 的量化.
- 转录组分析以确定与年龄相关的基因表达变化.
- 基因操纵以减少特定的组织蛋白变异,并观察对染色体分离的影响.
主要成果:
- 复制依赖的 (H3.1/H3.2) 和复制独立的 (H3.3) 基因组变异都随着卵细胞年龄的增长而减少.
- 与衰老相关的组素减少与转录基因变化相关,特别是与H3.3耗尽相关的变化.
- 基因减少H3.1/H3.2或H3.3并没有加速与年龄相关的过早染色体分离或介质性错误.
结论:
- 哺乳动物卵细胞的衰老导致染色体组质子的减少,影响基因表达模式.
- 尽管发生了转录基因变化,但观察到的基因素减少似乎不是生殖寿命期间介质分离错误的主要驱动因素.
相关概念视频
02:07Oogenesis
63.6K
In human women, oogenesis produces one mature egg cell or ovum for every precursor cell that enters meiosis. This process differs in two unique ways from the equivalent procedure of spermatogenesis in males. First, meiotic divisions during oogenesis are asymmetric, meaning that a large oocyte (containing most of the cytoplasm) and minor polar body are produced as a result of meiosis I, and again following meiosis II. Since only oocytes will go on to form embryos if fertilized, this unequal...
63.6K
02:38Heterochromatin
12.1K
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...
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...
12.1K
02:57Meiosis vs. Mitosis
54.8K
Cell division is necessary for growth and reproduction in organisms. Mitosis aids cell growth and development by dividing somatic cells. In contrast, meiosis causes the division of germ cells and plays an essential role in sexual reproduction. Due to their unique functional requirements, mitosis and meiosis differ from each other in multiple aspects.
Before the start of mitosis and meiosis I, the cell synthesizes DNA, resulting in two homologous copies of each chromosome. DNA synthesis is...
Before the start of mitosis and meiosis I, the cell synthesizes DNA, resulting in two homologous copies of each chromosome. DNA synthesis is...
54.8K
02:02Meiosis II
45.3K
Meiosis II entails cell division and segregation of the sister chromatids, resulting in the production of four unique haploid gametes. The steps for meiosis II are similar to mitosis, except that meiosis II occurs in haploid cells, whereas mitosis occurs in diploid cells.
The timing and cell division patterns of meiosis differ between males and females. In male meiosis, the centrosomes are part of the formation of the meiotic spindle. However, in oocytes, including that of humans, Drosophila,...
The timing and cell division patterns of meiosis differ between males and females. In male meiosis, the centrosomes are part of the formation of the meiotic spindle. However, in oocytes, including that of humans, Drosophila,...
45.3K
03:17Inheritance of Chromatin Structures
6.2K
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...
6.2K
01:21Nondisjunction
3.8K
Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate correctly and move to the opposite poles of the cells. This produces daughter cells with abnormal chromosome numbers. Nondisjunction is common during anaphase I or anaphase II of meiosis. Mutations in synaptonemal complex proteins that attach homologous chromosomes increase the chances of nondisjunction in anaphase I of meiosis I. In contrast, mutations in topoisomerases and condensins that hold...
3.8K