トランポゼス捕獲による脊椎動物の転写因子の再発性進化
Rachel L Cosby1, Julius Judd1, Ruiling Zhang1
1Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14850, USA.
まとめ
DNAトランポゾンは,エクソンシャッフリングを通じて新しいタンパク質コードの配列を提供することで,遺伝子進化を推進します. このプロセスは繰り返しKRAB-トランスポゼのような 調節性タンパク質を作り出し テトラポッドのゲノムを形作っています
科学分野:
- 進化の遺伝学
- 分子生物学
- ゲノミクス
背景:
- 新しい細胞機能とタンパク質の構造は エクソンシャッフルから生じます
- DNAトランポゾンは ゲノム進化に寄与できる 移動性遺伝的要素です
研究 の 目的:
- エクソンシャッフルのための遺伝物質を提供するDNAトランポゾンの役割を調査する.
- トランポゼドメインの捕獲と融合タンパク質の形成を特定する.
- 新しい融合タンパク質の機能,特にKRAB-トランスポゼ複合体の特徴づけ.
主な方法:
- テトラポッドの進化を比較したゲノム分析
- 代替スプライシングイベントに焦点を当てたトランスポゼドメイン融合の識別と特徴付け.
- 特定された融合タンパク質の遺伝子調節活性を決定する機能検査.
主要な成果:
- DNAトランポゾンは,エクソンシャッフリングのための遺伝物質を繰り返し供給し,約3億5000万年以上にわたって少なくとも94の独立した融合タンパク質形成につながった.
- トランスポザースのDNA結合ドメインは,主体の調節ドメイン,特にクリュッペル関連ボックス (KRAB) ドメインと頻繁に融合する.
- 4つの異なるKRAB-トランスポゼ融合タンパク質が特定され,それぞれが配列特異的な遺伝子抑制を可能にしました.
- コウモリ特有のKRABINER融合タンパク質は,標的トランポゾンに全ゲノム結合し,関連する遺伝子とシス調節要素を調節する.
結論:
- DNAトランポゾンは,エクソンシャッフリングによる新しいタンパク質をコードする遺伝子の進化の重要な源として機能する.
- KRAB-トランスポゼ融合タンパク質の繰り返し出現は,遺伝子調節の進化におけるその重要性を強調しています.
- KRABINERの例は,トランポゾン媒介の遺伝子融合イベントから新しい転写因子とその結合部位がどのように生じるかを示しています.
関連する概念動画
Overview of Transposition and Recombination
18.0K
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...
18.0K
DNA-only Transposons
15.7K
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...
15.7K
Transposons
606
Transposons, or "jumping genes," are small mobile genetic elements (MGEs) that range from 700 to 40,000 base pairs in length. They are found in all organisms and can move within the same chromosome or transfer to different chromosomes. In some cases, transposons can also jump between different host DNA molecules, such as plasmids or viruses, contributing to genetic variability.Barbara McClintock first discovered these mobile genetic elements in the 1940s while studying maize genetics, and she...
606
LTR Retrotransposons
18.7K
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...
18.7K
Non-LTR Retrotransposons
12.6K
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...
12.6K
Conservative Site-specific Recombination and Phase Variation
6.4K
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
6.4K


