一个小的螺旋捆通过结合两个核酸来准备初始合成,从而提高DNA模板的特定序列识别
Julien Boudet1, Jean-Christophe Devillier2, Thomas Wiegand3
1Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland.
Cell
|January 1, 2019
概括
考古原始酶使用螺旋束域 (HBD) 来绑定DNA模板. 核酸结合触发了全变化,使得序列特异性的DNA结合能够进行原始合成.
科学领域:
- 分子生物学
- 生物化学
- 结构生物学
背景情况:
- 原酶是DNA复制中的必不可少的酶,用于合成DNA聚合酶的原酶.
- 考古真核原始体具有催化和辅助域,辅助域的功能不清楚.
- 在 pRN1 考古原酶中,其辅助域为115氨基酸螺旋束域 (HBD).
研究的目的:
- 阐明了辅助螺旋束域 (HBD) 在古生物原酶介导的DNA复制中的结构和功能作用.
- 研究HBD与DNA模板和核酸三酸相互作用的机制.
主要方法:
- 使用液态和固态核磁共振 (NMR) 光谱来研究pRN1古生物原酶HBD的结构.
- 结构研究重点是DNA模板结合和核酸三相互作用的影响.
主要成果:
- 单独的HBD将DNA模板结合起来,独立于催化域.
- 在结合两个核酸三时,HBD转换为特定序列的DNA结合.
- 这种核酸结合会诱导HBD显著的形变化.
结论:
- 通过结合DNA模板并促进特定序列的识别,HBD在启动DNA复制方面发挥着至关重要的作用.
- HBD 作为支架,将基板 (DNA 模板和核酸) 接近,用于初始合成.
- 这种机制很可能在古核细胞原生体中保留,突出显示了DNA复制启动的有效策略.
相关概念视频
DNA as a Genetic Template
27.8K
Two structural features of the DNA molecule provide a basis for the mechanisms of heredity: the four nucleotide bases and its double-stranded nature. The Watson-Crick model of double-helical DNA structure, proposed in 1952, drew heavily upon the X-ray crystallography work of researchers Rosalind Franklin and Maurice Wilkins. Watson, Crick, and Wilkins jointly received the Nobel Prize in Physiology or Medicine for their work in 1962. Franklin was, controversially, excluded from the prize for...
27.8K
DNA as a Genetic Template
9.5K
9.5K
DNA Replication
59.3K
DNA replication involves the separation of the two strands of the double helix, with each strand serving as a template from which the new complementary strand is copied. After replication, each double-stranded DNA includes one parental or “old” strand and one “new” strand. This is known as semiconservative replication. The resulting DNA molecules have the same sequence and are divided equally into the two daughter cells.
Replication in Prokaryotes
DNA replication...
Replication in Prokaryotes
DNA replication...
59.3K
From DNA to Protein
22.4K
The flow of genetic information in cells from DNA to mRNA to protein is described by the central dogma, which states that genes specify the sequence of mRNAs, which in turn specify the sequence of amino acids making up all proteins. The decoding of one molecule to another is performed by specific proteins and RNAs. Because the information stored in DNA is so central to cellular function, it makes intuitive sense that the cell would make mRNA copies of this information for protein synthesis...
22.4K
Cis-regulatory Sequences
11.8K
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...
11.8K
Conservative Site-specific Recombination and Phase Variation
6.8K
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...
The recognition sites for Cre recombinase called LoxP...
6.8K


