ヌクレオチドの長さとコソリュート構造による分子混雑がDNA複合体の安定性に与える影響
Shu-ichi Nakano1, Hisae Karimata, Tatsuo Ohmichi
1Frontier Institute for Biomolecular Engineering Research (FIBER), and Department of Chemistry, Faculty of Science and Engineering, Konan University, 8-9-1 Okamoto, Higashinada-ku, Kobe 658-8501, Japan.
Journal of the American Chemical Society
|November 4, 2004
まとめ
エチレングリコール (EG) やポリエチレングリコール (PEG) などのコソルートの高濃度は,DNA複合体の安定性に影響を及ぼします. 水の活性低下は,短いDNA複合体を不安定化させ,核酸の機能に影響を与えるための鍵です.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- 物理化学 物理化学
背景:
- 細胞核酸の構造と機能は溶液状態によって影響を受けます.
- コソリュート溶液におけるDNA二重体熱力学を理解することは,細胞のプロセスにとって極めて重要です.
研究 の 目的:
- 高濃度のコソリュートでDNA複合体の熱力学を研究する.
- コソリュート型と分子量がDNA二重複の安定性にどのように影響するかを決定する.
- DNA二重複形成における水活動と核酸溶解の役割を明らかにする.
主な方法:
- DNA二重構造の熱力学的分析.
- 異なる分子量を持つエチレングリコール (EG) とポリエチレングリコール (PEG) の様々な濃度を用いた調査.
- 塩基対形成中の水活動と水吸収の測定.
主要な成果:
- DNAのデュプレックス安定性は,ニュクレオチド長さとPEGサイズによって変化した.
- 短い (8-mer) のデュプレックスの主要な不安定化要因として,水の活動が低下することが特定されました.
- 塩基対あたりの水吸収量は,コソルト構造に基づいて異なっており,異なる核酸溶解を示唆しています.
結論:
- コソルトの濃度とタイプは,DNAのダプレックス熱力学に大きな影響を与える.
- 水の活動と溶解効果は,細胞環境におけるDNAの振る舞いを理解するために重要である.
- 発見は,治療および診断用途のオリゴヌクレオチドの設計に役立ちます (例えば,アンチセンセス核酸,RNAi,DNAチップなど).
関連する概念動画
01:03Single-Strand DNA Binding Proteins
16.4K
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...
16.4K
02:05DNA as a Genetic Template
27.2K
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...
27.2K
01:53RNA Stability
35.5K
Intact DNA strands can be found in fossils, while scientists sometimes struggle to keep RNA intact under laboratory conditions. The structural variations between RNA and DNA underlie the differences in their stability and longevity. Because DNA is double-stranded, it is inherently more stable. The single-stranded structure of RNA is less stable but also more flexible and can form weak internal bonds. Additionally, most RNAs in the cell are relatively short, while DNA can be up to 250 million...
35.5K
01:25Nucleic Acid Structure
8.3K
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...
8.3K
02:02DNA Topoisomerases
34.5K
Topoisomerases are enzymes that relax overwound DNA molecules during various cell processes, including DNA replication and transcription. These enzymes regulate positive and negative DNA supercoiling without changing the nucleotide sequence. DNA overwinding in a clockwise direction results in positively supercoiled DNA, whereas underwinding in a counterclockwise direction produces negatively supercoiled DNA.
Types and Mechanism of action
Topoisomerases are divided into two main types. ...
Types and Mechanism of action
Topoisomerases are divided into two main types. ...
34.5K
02:04Fixing Double-strand Breaks
14.2K
The double-stranded structure of DNA has two major advantages. First, it serves as a safe repository of genetic information where one strand serves as the back-up in case the other strand is damaged. Second, the double-helical structure can be wrapped around proteins called histones to form nucleosomes, which can then be tightly wound to form chromosomes. This way, DNA chains up to 2 inches long can be contained within microscopic structures in a cell. A double-stranded break not only damages...
14.2K