ロックされた核酸を含む単一鎖および二重鎖DNAのチミン光分解の適合制御 TTステップ
Mahesh Hariharan1, Martin McCullagh, George C Schatz
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|August 26, 2010
まとめ
ロックされた核酸 (LNA) は,DNAのチミン-チミン光二分化を促進します. この形状制御により,光産物形成の効率と選択性が著しく向上します.
科学分野:
- フォトケミストリー フォトケミストリー
- 分子生物学は分子生物学である.
- 核酸化学 核酸化学について
背景:
- ティミン-ティミン光二酸化は,DNA損傷の重要な経路です.
- DNAの光分解の理解は,DNA修復と光保護の戦略に不可欠です.
- ロックされた核酸 (Locked nucleic acids,LNA) は,結合親和性と安定性を高め,化学的に改変された核酸である.
研究 の 目的:
- 鎖核酸がDNAにおけるチミン-チミン光二分化に及ぼす影響を調査する.
- フォトダイメリゼーション結果の制御における基底状態コンフォームの役割を解明する.
- 光産物形成の量子収量と選択性に対するLNAの影響を決定する.
主な方法:
- 統合された実験的 (光谱学,結晶学) と理論的 (計算モデリング) のアプローチ.
- ロックされた核酸チミン-チミン (LNA TT) を含む短い単一鎖および二重鎖DNAの合成ステップ.
- 紫外線照射とフォト製品の分析.
主要な成果:
- ロックされた核酸は,チミン-チミン光二分化の量子産量を大幅に増加させます.
- LNAによる形状制御は,光産物形成の選択性を高めます.
- 実験的および理論的データは,LNA媒介による光分解のメカニズム的理解を提供します.
結論:
- ロックされた核酸は,DNAの光分解プロセスを調節するために利用できます.
- 基底状態の形状制御は,核酸の光化学反応を強化するための強力な戦略です.
- この研究は,光化学とDNA損傷/修復の研究におけるLNAの応用に関する洞察を提供します.
さらに関連する動画
関連する概念動画
Translesion DNA Polymerases
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...
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...
Single-Strand DNA Binding Proteins
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...
DNA Topoisomerases
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. Type I...
Types and Mechanism of action
Topoisomerases are divided into two main types. Type I...
Proofreading
Synthesis of new DNA molecules starts when DNA polymerase links nucleotides together in a sequence that is complementary to the template DNA strand. DNA polymerase has a higher affinity for the correct base to ensure fidelity in DNA replication. The DNA polymerase furthermore proofreads during replication, using an exonuclease domain that cuts off incorrect nucleotides from the nascent DNA strand.Errors during Replication Are Corrected by the DNA Polymerase EnzymeGenomic DNA is synthesized in...
Maxam-Gilbert Sequencing
In the same year as the discovery of the Sanger sequencing method, another group of scientists, Allan Maxam and Walter Gilbert, demonstrated their chemical-cleavage method for DNA sequencing. The Maxam-Gilbert method relies on using different chemicals that can cleave the DNA sequence at specific sites, the separation of resulting DNA fragments of variable size using electrophoresis, and deciphering the DNA sequence from the resulting gel bands.
Challenges of the Maxam-Gilbert Method
The...
Challenges of the Maxam-Gilbert Method
The...
DNA Damage can Stall the Cell Cycle
In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...


