相关实验视频
Updated: Jun 26, 2026
14:23
Recombineering Homologous Recombination Constructs in Drosophila
Published on: July 13, 2013
概括
多瘤病毒大T抗原 (T-Ag) 通过在集成原点启动复制来促进病毒DNA切除或放大. 这种依赖复制的过程促进了随后的重组事件,突出了T-Ag的关键作用.
科学领域:
- 分子生物学分子生物学
- 病毒学 病毒学
- 遗传学 是一个遗传学.
背景情况:
- 多瘤病毒 (Py) 在宿主细胞中的DNA集成可以导致切除或放大.
- 这些过程需要病毒DNA同质性和功能性大T抗原 (T-Ag).
- 在这些事件中T-Ag (复制性与重组促进性) 的确切作用仍然不清楚.
研究的目的:
- 阐明多瘤病毒大T抗原 (T-Ag) 介导综合病毒DNA的切除和放大机制.
- 确定T-Ag在这些现象中的主要功能是复制性还是促进重组的.
主要方法:
- 研究了转变的老鼠细胞系,其中包含了 ts-a 多细胞瘤病毒插入,缺乏复制来源.
- 在可允许的温度下对可热性T-Ag进行评估的切除/放大.
- 将具有病毒复制起源和G418抗性基因的重组等离子体引入到起源缺陷细胞中.
- 在允许的T-Ag条件下分析G418耐药克隆进行放大.
主要成果:
- 带有原始缺陷多瘤病毒插入的细胞没有显示可检测的切除或放大,即使具有功能T-Ag.
- 引入含有多瘤病毒复制原点的等离子体,使集成序列的T-Ag依赖放大成为可能.
- T-Ag促进了DNA序列的转基因放大,这些序列包含了多瘤病毒的起源.
结论:
- 多瘤病毒大T抗原 (T-Ag) 主要通过在集成的病毒源处启动复制来促进病毒DNA切除和放大.
- 通过T-Ag启动复制,产生了有利于随后重组事件的基质.
- 这表明T-Ag在转化细胞内的病毒DNA不稳定性中具有复制性作用.
相关概念视频
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The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
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The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
02:08Gene Conversion
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02:37Gene Duplication and Divergence
The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
03:01The Replisome
DNA replication is carried out by a large complex of proteins that act in a coordinated matter to achieve high-fidelity DNA replication. Together this complex is known as the DNA replication machinery or the replisome.
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
02:31Homologous Recombination
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...