概括
谢诺普斯卵细胞核提取物准确地从重组DNA中转录5SRNA基因. RNA聚合酶III负责90%以上的转录,包括病毒RNA合成.
科学领域:
- 分子生物学分子生物学
- 基因表达 基因表达
- RNA合成 RNA合成
背景情况:
- 精确的转录真核基因需要特定的核因子.
- 谢诺普斯·莱维斯 (Xenopus laevis) 的卵细胞具有强大的转录系统.
- 重组DNA技术允许研究特定的基因转录.
研究的目的:
- 为了研究Xenopus 5SRNA基因的精确转录在体外.
- 为了确定负责5SRNA合成的RNA聚合酶.
- 在Xenopus卵细胞核提取物中描述复合DNA的转录.
主要方法:
- 从Xenopus laevis卵细胞中制备一个核浮分子部分.
- 使用含有Xenopus 5SRNA基因的重组塑进行转录试验.
- 通过凝电泳和寡核酸指纹识别分析合成的RNA.
- 使用alpha-amanitin识别RNA聚合酶活性的抑制研究.
主要成果:
- 核上位分数准确地转录了Xenopus 5SRNA基因.
- 转录表现出一个滞后阶段,随后是持续的合成速率.
- RNA聚合酶III转录了超过90%的总RNA合成.
- 亚地诺病毒2的DNA也被RNA聚合酶III转录,产生与病毒相关的RNA1.1.
结论:
- 类卵细胞核提取物为研究5SRNA基因转录提供了一个系统.
- 在这种系统中,RNA聚合酶III在内源性和病毒性DNA的转录中起着重要作用.
- 转录效率受到DNA度和离子条件的影响.
相关概念视频
RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
Ribosomal RNA Synthesis
Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
Methods of Nuclear Reprogramming
Nuclear reprogramming is a process of transforming one cell type into an unrelated cell type by epigenetic changes that alter the cell’s original gene expression pattern. Such epigenetic changes force cells to express a different set of genes, which play a significant role in inducing transformation into other cell types. Nuclear reprogramming offers applications in reproductive cloning for livestock propagation and regenerative medicine — developing patient-specific cells for injury repair.


