相关实验视频
Updated: Apr 4, 2026

16:24
Analyzing and Building Nucleic Acid Structures with 3DNA
Published on: April 26, 2013
21.4K
作为太阳辐射的首选目标的核基的非正规堆叠几何
Ruslan R Ramazanov1, Dmitriy A Maksimov1, Alexei I Kononov1
1Department of Molecular Biophysics and Polymer Physics, St. Petersburg State University , 7/9 Universitetskaya nab., St. Petersburg 199034 Russia.
Journal of the American Chemical Society
|August 28, 2015
概括
导致皮肤癌的紫外线对DNA的敏感性不是随机的. 扭曲的DNA结构, 像发针中发现的, 更容易吸收UVB辐射, 潜在地识别癌症"热点".
科学领域:
- 摄影化学
- 分子生物物理学
- 遗传学
背景情况:
- 通过DNA直接吸收UVB光子 (290-320nm) 会引起环丁二聚体,这是皮肤癌发病的主要机制.
- 这些UVB诱导的DNA损伤的形成不是随机的,特定的"热点"更容易受到伤害,但它们的构造基础尚不清楚.
研究的目的:
- 通过各种构造来研究堆叠的DNA基的电子激发光谱 (氨酸,细胞酸,腺素).
- 确定DNA结构如何影响UVB辐射的吸收,并确定潜在的病变形成热点.
主要方法:
- 使用ab initio方法计算堆叠的氨酸,氨酸和氨酸二聚体的电子激发光谱.
- 分析了由蛋白质数据库 (PDB) 和分子动力学模拟所获得的广泛的构造.
主要成果:
- 与标准的B型DNA相比,堆叠的二极体具有扭曲的DNA形状 (曲的,类似发针的) 显示激发性转移红移高达0.6 eV.
- 这些扭曲的结构中减少的基间距离增强了UVB吸收,使它们成为太阳辐射的首选目标.
结论:
- DNA 构造对UVB 吸收有显著影响,扭曲的结构作为光损伤的首选目标.
- 这些发现为预测UVB诱导的DNA损伤的热点提供了分子基础, 这对于了解皮肤癌的发展至关重要.
相关概念视频
Nucleic Acid Structure
10.3K
The pentose sugar in DNA is deoxyribose, while in RNA the pentose sugar is ribose. The difference between the sugars is the presence of the hydroxyl group on the ribose's second carbon and a hydrogen on the deoxyribose's second carbon. The phosphate residue attaches to the hydroxyl group of the 5′ carbon of one sugar and the hydroxyl group of the 3′ carbon of the sugar of the next nucleotide, which forms a 5′ to 3′ phosphodiester linkage.
DNA Structure
DNA...
DNA Structure
DNA...
10.3K
DNA Base Pairing
35.8K
Erwin Chargaff’s rules on DNA equivalence paved the way for the discovery of base pairing in DNA. Chargaff’s rules state that in a double-stranded DNA molecule,
35.8K
DNA Base Pairing
33.5K
33.5K
Single-Strand DNA Binding Proteins
17.2K
For successful DNA replication, the unwinding of double-stranded DNA must be accompanied by stabilization and protection of the separated single strands of the DNA. This crucial task is performed by single-strand DNA-binding (SSB) proteins. They bind to the DNA in a sequence-independent manner, which means that the nitrogenous bases of the DNA need not be present in a specific order for binding of SSB proteins to it. The binding of SSB proteins straightens single-stranded DNA (ssDNA) and makes...
17.2K
Mutations
45.6K
Mutations are changes in the sequence of DNA. These changes can occur spontaneously or they can be induced by exposure to environmental factors. Mutations can be characterized in a number of different ways: whether and how they alter the amino acid sequence of the protein, whether they occur over a small or large area of DNA, and whether they occur in somatic cells or germline cells.
Chromosomal Alterations Are Large-Scale Mutations
While point mutations are changes in a single nucleotide in...
Chromosomal Alterations Are Large-Scale Mutations
While point mutations are changes in a single nucleotide in...
45.6K
Nucleic Acids and Nucleotides
16.5K
Nucleic acids are the most important macromolecules for the continuity of life. They carry the cell's genetic blueprint and have instructions for its functioning. The two main types of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
Deoxyribonucleic Acid (DNA)
DNA is the genetic material in all living organisms, ranging from single-celled bacteria to multicellular mammals. It is in the nucleus of eukaryotes and the organelles such as chloroplasts and mitochondria....
Deoxyribonucleic Acid (DNA)
DNA is the genetic material in all living organisms, ranging from single-celled bacteria to multicellular mammals. It is in the nucleus of eukaryotes and the organelles such as chloroplasts and mitochondria....
16.5K

