小卫星RNA功能在小鼠胚胎干细胞染色体分离中的决定因素
Yung-Li Chen1, Alisha N Jones2, Amy Crawford3
1Institute of Epigenetics and Stem Cells (IES), Helmholtz Munich , München, Germany.
The Journal of cell biology
|April 16, 2024
概括
中心RNA转录,特别是小卫星 (MinSat) RNA,对于染色体分离至关重要. 它们的茎环结构,而不是序列,是它们功能和跨物种保护的关键.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 中心分子在细胞分裂期间对染色体分离至关重要.
- 由于重复的低序列保存,中心转录的作用受到争论.
- 一个假设提出通过RNA二级结构的功能.
研究的目的:
- 为了研究中心体转录的功能,特别是小卫星 (MinSat) RNA.
- 为了确定RNA的二次结构,而不是序列保存,是底层的中心转录函数.
- 确定MinSat转录影响染色体分离的机制.
主要方法:
- 使用了小鼠胚胎干细胞 (ESC).
- 分析了改变的MinSat转录水平对染色体分离的影响.
- 研究了MinsatRNA二次结构及其在人类α卫星转录中的保存.
- 在CENPC中确定了RNA结合区域,并测试了突变RNA.
主要成果:
- 不平衡的MinSat转录水平会导致严重的染色体分离缺陷.
- MinSat RNA 形成了一个保存的干循环二次结构.
- 敏卫星转录通过其结构区域运行,与CENPC互动.
- 破坏MinSat的二级结构取消了分离缺陷.
结论:
- 中心转录可能通过保存的二级RNA结构运行,而不是序列.
- 敏卫星RNA的二级结构对于其在忠实染色体分离中的作用至关重要.
- 这一发现使中心体重复的低序列保存与中心体转录的保存函数相协调.
相关概念视频
02:02Meiosis II
45.6K
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,...
45.6K
02:54Nucleosome Remodeling
9.1K
Nucleosomes are the basic units of chromatin compaction. Each nucleosome consists of the DNA bound tightly around a histone core, which makes the DNA inaccessible to DNA binding proteins such as DNA polymerase and RNA polymerase. Hence, the fundamental problem is to ensure access to DNA when appropriate, despite the compact and protective chromatin structure.
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
9.1K
02:41Chromatin Structure Regulates pre-mRNA Processing
7.0K
In eukaryotic cells, nascent mRNA transcripts need to undergo many post-transcriptional modifications to reach the cell cytoplasm and translate into functional proteins. For a long time, transcription and pre-mRNA processing were considered two independent events that occur sequentially in the cell. However, it has now been well established that transcription and pre-mRNA processing are two simultaneous processes that are precisely regulated inside the cell.
The chromatin structure, especially...
The chromatin structure, especially...
7.0K
02:19The Spindle Assembly Checkpoint
3.2K
The spindle assembly checkpoint is a molecular surveillance mechanism ensuring the fidelity of chromosome segregation during anaphase. The checkpoint monitors the completion of all the prerequisite steps before chromosome segregation to determine whether the segregation process should proceed or be delayed.
Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
3.2K
02:17Separation of Sister Chromatids
3.6K
At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
At the onset of anaphase, separase, a proteolytic enzyme, is...
At the onset of anaphase, separase, a proteolytic enzyme, is...
3.6K
02:57Meiosis vs. Mitosis
55.4K
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...
55.4K