概括
胚胎白肌细胞在分化过程中调节核糖体的产生. 融合后,rRNA合成继续,但降解增加,减少肌肉纤维中的核糖体积累.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 发育生物学 发展生物学
背景情况:
- 核糖体对于蛋白质合成和细胞生长至关重要.
- 核糖体生物发生在细胞分化过程中受到严格调节.
- 了解rRNA动态对于理解细胞发育至关重要.
研究的目的:
- 为了研究核糖体RNA (rRNA) 的合成,积累和稳定性,在区分长菌体中.
- 阐明控制肌细胞融合和纤维形成过程中的核糖体含量机制.
主要方法:
- 胚胎白肌细胞的细胞培养.
- 使用3H-甲基-氨酸测量rRNA稳定性的脉冲追踪实验.
- 分析3H-腺在rRNA和ATP池中的结合,以评估rRNA合成速率.
主要成果:
- 分裂的神经细胞通过将rRNA积累与细胞分裂相匹配来保持恒定的核糖体含量.
- 融合后,肌肉纤维中的核糖体积累显著减少 (到四分之一的分裂肌细胞的速度).
- 分化纤维中的rRNA的半衰期为45小时;在加工过程中的降解占了减少核糖体形成的很大一部分.
结论:
- 在分化过程中, Quail 菌根细胞调节核糖体生物发生.
- 在加工过程中增加的rRNA降解,以及rRNA周转,解释了肌肉纤维中的核糖体积累减少.
- 这些调节机制确保了适当的核糖体水平,以实现分化的细胞功能.
相关概念视频
Regulation of Expression Occurs at Multiple Steps
Gene expression can be regulated at almost every step from gene to protein. Transcription is the step that is most commonly regulated. This involves the binding of proteins to short regulatory sequences on the DNA. This association can either promote or inhibit the transcription of a gene associated with the respective sequence.
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Master Transcription Regulators
Master transcription regulators are regulatory proteins that are predominantly responsible for regulating the expression of multiple genes. Often these genes work in concert to drive a complex process. Activation of a master transcription regulator can lead to a cascade of transcriptional activation necessary for that outcome. These regulators can directly bind to the regulatory sequences of the various genes involved, or they can indirectly regulate transcription by binding to regulatory...
Regulated mRNA Transport
In eukaryotes, transcription and translation are compartmentalized; an mRNA is first synthesized in the nucleus and then selectively transported to the cytoplasm for protein synthesis. Before transport, a pre-mRNA undergoes several steps of post-transcriptional modifications including splicing, 5' capping, and the addition of a poly-adenine tail. Various proteins bind to the pre-mRNA during these modifications. The mRNA transport takes place with the help of multiple proteins playing specific...
Regulation of Expression Occurs at Multiple Steps
Gene expression can be regulated at almost every step from gene to protein. Transcription is the step that is most commonly regulated. This involves the binding of proteins to short regulatory sequences on the DNA. This association can either promote or inhibit the transcription of a gene associated with the respective sequence.
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Regulated mRNA Transport
In eukaryotes, transcription and translation are compartmentalized; an mRNA is first synthesized in the nucleus and then selectively transported to the cytoplasm for protein synthesis. Before transport, a pre-mRNA undergoes several steps of post-transcriptional modifications including splicing, 5' capping, and the addition of a poly-adenine tail. Various proteins bind to the pre-mRNA during these modifications. The mRNA transport takes place with the help of multiple proteins playing specific...
Regulation of Expression at Multiple Steps
The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. Transcriptional regulation is mediated by regulatory proteins such as transcription factors, activators, or repressors—these control gene expression by initiating or inhibiting the transcription of genes. Once a precursor or pre-mRNA is produced, it undergoes post-transcriptional modification, including 5' capping, splicing, and the addition of a...


