DNA オリガミロータを使用したゲノム処理酵素の回転追跡
Pallav Kosuri1,2,3, Benjamin D Altheimer1,2,3,4, Mingjie Dai4,5,6
1Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA.
Nature
|July 19, 2019
まとめ
研究者らは,リアルタイムでDNAの回転を正確に測定するために,オリガミ・ローターベースのイメージングと追跡 (ORBIT) という新しい方法を開発しました. この技術はミリ秒の解像度を提供し DNAの修復と転写過程の理解を深めています
科学分野:
- 分子生物学
- バイオ物理学
- ゲノミクス
背景:
- 転写や複製のようなゲノム処理反応には DNAの回転が含まれます
- DNAの回転を測定する既存の方法は,生理学的条件下で多くの酵素を研究するために必要な時間解像度とスループットを欠いている.
研究 の 目的:
- 単一分子レベルでDNAの回転を追跡するための高解像度の新しい方法を導入します.
- DNAとタンパク質の相互作用の研究における既存の技術の限界を克服する.
主な方法:
- オリガミ・ロータベースの画像と追跡 (ORBIT) の開発
- DNAの回転をミリ秒解像度で追跡するために,光で標識されたDNAオリガミの回転器を使用します.
- RecBCD複合体とRNAポリメラーゼ (RNAP) の活性を研究するためのアプリケーション.
主要な成果:
- ORBITは,RecBCD複合体とRNAPによって誘発されたDNAの回転を成功裏に追跡しました.
- 開始,転位,一時停止,およびバックトラッキングを含むRecBCD媒介の解き放たれイベントの詳細な特徴.
- リバーシブルなATP無依存の解き放たれとRecBモータの関与を含むRecBCDのイニシアチブメカニズムを明らかにした.
- RNAP転写中の単塩基対解のステップを直接観察する.
結論:
- ORBITは,単一分子DNAの回転を追跡するために,前例のないミリ秒レベルの解像度を提供します.
- この方法は,RecBCDのようなDNA修復酵素とRNAPのような転写機構の複雑なメカニズムを明らかにします.
- ORBITはタンパク質とDNAの相互作用に関するより広範な調査を容易にする見込みです.
関連する概念動画
Genomic DNA in Prokaryotes
48.4K
The genome of most prokaryotic organisms consists of double-stranded DNA organized into one circular chromosome in a region of cytoplasm called the nucleoid. The chromosome is tightly wound, or supercoiled, for efficient storage. Prokaryotes also contain other circular pieces of DNA called plasmids. These plasmids are smaller than the chromosome and often carry genes that confer adaptive functions, such as antibiotic resistance.
Genomic Diversity in Bacteria
Although bacterial genomes are much...
Genomic Diversity in Bacteria
Although bacterial genomes are much...
48.4K
Genomic DNA in Eukaryotes
52.4K
Eukaryotes have large genomes compared to prokaryotes. To fit their genomes into a cell, eukaryotic DNA is packaged extraordinarily tightly inside the nucleus. To achieve this, DNA is tightly wound around proteins called histones, which are packaged into nucleosomes that are joined by linker DNA and coil into chromatin fibers. Additional fibrous proteins further compact the chromatin, which is recognizable as chromosomes during certain phases of cell division.
52.4K
Genomics
39.8K
Genomics is the science of genomes: it is the study of all the genetic material of an organism. In humans, the genome consists of information carried in 23 pairs of chromosomes in the nucleus, as well as mitochondrial DNA. In genomics, both coding and non-coding DNA is sequenced and analyzed. Genomics allows a better understanding of all living things, their evolution, and their diversity. It has a myriad of uses: for example, to build phylogenetic trees, to improve productivity and...
39.8K
DNA-only Transposons
17.3K
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...
The donor site from where the transposon is excised is either degraded or...
17.3K
DNA Topoisomerases
35.1K
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. ...
35.1K
Enzymes
93.9K
Inside living organisms, enzymes act as catalysts for many biochemical reactions involved in cellular metabolism. The role of enzymes is to reduce the activation energies of biochemical reactions by forming complexes with its substrates. The lowering of activation energies favor an increase in the rates of biochemical reactions.
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
93.9K


