関連する実験動画
Updated: May 10, 2026

11:52
Analysis of LINE-1 Retrotransposition at the Single Nucleus Level
Published on: April 23, 2016
LINE-1の逆転移によって作られたゲノム削除
Nicolas Gilbert1, Sheila Lutz-Prigge, John V Moran
1Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109, USA. gilbertn@umich.edu
Cell
|August 15, 2002
まとめ
LINE-1の逆変換は,様々な統合経路を通じてヒトゲノムに影響を与えます. この研究は,LINE-1の活動が,単純な挿入ではなく,大規模な削除を引き起こし,キメリック要素を形成することを明らかにしています.
科学分野:
- 遺伝学 遺伝学とは
- 分子生物学は分子生物学である.
- ゲノミクスゲノミクスとは
背景:
- LINE-1 (L1) レトロトランポゾンとは,ヒトゲノムに活性化している移動性遺伝要素である.
- L1がDNAに統合される正確なメカニズムは,まだ完全に理解されていない.
研究 の 目的:
- 培養ヒト細胞におけるLINE-1レトロトランスポーソンの統合メカニズムを調査する.
- L1 リトロトランスポーゼーションイベントの構造的結果の特徴づけ.
主な方法:
- L1レトロトランスポジションイベントを捕捉するためのプラズミドベースの救助システムの開発.
- シーケンシングを用いた培養ヒト細胞から新たに回収された37件のL1挿入イベントの分析.
主要な成果:
- 典型的な構造的特徴を持つ37の新しいL1逆転移イベントを特定しました.
- 4つのL1統合インスタンスで大規模なターゲットサイト削除が観察されました.
- 内生的なL1配列と人工的なL1配列の融合によって形成された3つのキメリックL1元素を発見した.
結論:
- L1統合の複数の経路がヒト細胞に示されている.
- L1の逆転移は,単に挿入だけでなく,重要なゲノム削除につながる可能性があることが判明しました.
- 単純な挿入イベントを超えたL1変異性の複雑な性質を強調しました.
関連する概念動画
Gene Conversion
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
Overview of Transposition and Recombination
Transposons make up a significant part of genomes of various organisms. Therefore, it is believed that transposition played a major evolutionary role in speciation by changing genome sizes and modifying gene expression patterns. For example, in bacteria, transposition can lead to conferring antibiotic resistance. Movement of transposable elements within the genetic pool of pathogenic bacteria can aid in transfer of antibiotic-resistant genetic elements. In eukaryotes, transposons can carry out...
DNA-only Transposons
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...
Retroviruses
Retroviruses and retrotransposons both insert copies of their genetic elements into the genome of the host cell. Thus, the viral genes are passed on when the host genome is replicated or translated. A typical retroviral DNA sequence contains 3-4 genes that encode the different proteins required for its structural assembly and function as a molecular parasite. This DNA is transcribed into a single mRNA, which is very similar in structure to conventional mRNAs, i.e., it is capped at the 5’...
LTR Retrotransposons
LTR retrotransposons are class I transposable elements with long terminal repeats flanking an internal coding region. These elements are less abundant in mammals compared to other class I transposable elements. About 8 percent of human genomic DNA comprises LTR retrotransposons. Some of the common examples of LTR retrotransposons are Ty elements in yeast and Copia elements in Drosophila.
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
Non-LTR Retrotransposons
As the name suggests, non-LTR retrotransposons lack the long terminal repeats characteristic of the LTR retrotransposons. Additionally, both LTR and non-LTR retrotransposons use distinct mechanisms of mobilization. Non-LTR retrotransposons are further divided into two classes - Long interspersed nuclear elements (LINEs) and short interspersed nuclear elements (SINEs), both of which occur abundantly in most mammals, including humans. Some of the active non-LTR retrotransposons in humans are L1...

