TnsABCD转基因的结构揭示了向DNA转基因的机制
These videos have been matched automatically. Contact us if they are not relevant.
These videos have been matched automatically. Contact us if they are not relevant.
在PubMed上查看摘要
概括
此摘要是机器生成的。使用TnsD和TnsABC蛋白质精确插入DNA. 化EM结构揭示了TnsD如何曲DNA,TnsC有助于针对性基因组编辑应用的转基因组组装.
科学领域
- 分子生物学
- 结构生物学
- 遗传学
背景情况
- 类似Tn7的转子是以其精确的染色体插入能力而闻名的移动遗传元素.
- 转移过程涉及TnsD蛋白质识别特定的附着点 (att),并招募其他Tns蛋白质形成功能转移体.
- 尽管确立了该途径,但转基因组合和DNA相互作用的详细原子级结构信息是有限的.
研究的目的
- 阐明涉及Tn7类转换的关键复合物的原子层结构.
- 提供TnsD对att位点的识别和TnsABCD转基因组的后续组装的机制性见解.
- 了解TnsC在招募TnsAB中的作用及其在转基因组形成中的直接参与.
主要方法
- 使用冷电子显微镜 (cryo-EM) 来确定高分辨率结构.
- 获得了TnsC-TnsD-att DNA复合体和完整的TnsABCD转基因.
- 这项研究重点是来自Peltigera membranacea 210A的CRISPR相关的I型转体.
主要成果
- 冷-EM结构显示了att DNA的显著曲,由TnsD阿基因侧链插入CC/GG二核酸阶段引起.
- TnsABCD转基因的结构阐明了关键的TnsA-TnsB相互作用.
- 这表明TnsC具有双重作用:招募TnsAB复合体,并直接参与转基因组合.
结论
- 这项研究提供了前所未有的原子级结构洞察力,
- 这些发现澄清了TnsD在DNA曲和TnsC在转基因组合中的作用.
- 这些结构和机制见解对提高利用转位子的基因组编辑技术的精度和效率具有重要意义.
相关概念视频
DNA-only transposons are called autonomous transposons since they code for the enzyme transposase that is required for the transposition mechanism. Insertion of transposons can alter gene functions in multiple ways. They can mutate the gene, alter gene expression by introducing a novel promoter or insulator sequence, introduce new splice sites, and change the mRNA transcripts produced, or remodel chromatin structure.
The donor site from where the transposon is excised is either degraded or...
Transposons make up a significant part of genomes of various organisms. Therefore, it is believed that transposition played a major evolutionary role in speciation by changing genome sizes and modifying gene expression patterns. For example, in bacteria, transposition can lead to conferring antibiotic resistance. Movement of transposable elements within the genetic pool of pathogenic bacteria can aid in transfer of antibiotic-resistant genetic elements. In eukaryotes, transposons can carry out...
LTR retrotransposons are class I transposable elements with long terminal repeats flanking an internal coding region. These elements are less abundant in mammals compared to other class I transposable elements. About 8 percent of human genomic DNA comprises LTR retrotransposons. Some of the common examples of LTR retrotransposons are Ty elements in yeast and Copia elements in Drosophila.
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
Translesion (TLS) polymerases rescue stalled DNA polymerases at sites of damaged bases by replacing the replicative polymerase and installing a nucleotide across the damaged site. Doing so, TLS allows additional time for the cell to repair the damage before resuming regular DNA replication.
TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...
As the name suggests, non-LTR retrotransposons lack the long terminal repeats characteristic of the LTR retrotransposons. Additionally, both LTR and non-LTR retrotransposons use distinct mechanisms of mobilization. Non-LTR retrotransposons are further divided into two classes - Long interspersed nuclear elements (LINEs) and short interspersed nuclear elements (SINEs), both of which occur abundantly in most mammals, including humans. Some of the active non-LTR retrotransposons in humans are L1...
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...