遺伝子の複製の後,パラログ干渉は転写回路の進化を制約する
Christopher R Baker1, Victor Hanson-Smith, Alexander D Johnson
1Department of Immunology and Microbiology, University of California, San Francisco, CA 94143, USA.
まとめ
遺伝子の複製は,パラログの間の競争的干渉につながり,特に協力的なアセンブリのタンパク質のために. この干渉を解消すると,Mcm1調節器で見られるように,分子複雑性が増加し,重複した遺伝子を安定させます.
科学分野:
- 進化生物学の進化生物学について
- 分子遺伝学 分子遺伝学
- システム生物学 システム生物学
背景:
- 遺伝子の複製モデルでは,しばしば独立した祖先の機能が想定されます.
- 協同組成のタンパク質は,トランスクリプションのレギュレータと同様に,複製後のユニークな進化的圧力に直面する可能性があります.
- MADSボックスの転写調節体Mcm1は,真菌に不可欠であり,多数の遺伝子を制御する.
研究 の 目的:
- 協力的なタンパク質集合における遺伝子複製の結果としてのパラログ干渉を調査する.
- Mcm1遺伝子とその類似遺伝子の進化史を検証する.
- パラログ干渉の解像度が遺伝子調節ネットワークの複雑性にどのように影響するかを理解する.
主な方法:
- キノコ種間のMcm1遺伝子配列の比較分析.
- タンパク質の相互作用と規制ネットワークのダイナミクスのモデリング.
- 歴史的置換を推論するための系統遺伝分析.
主要な成果:
- Mcm1のような転写レギュレータの重複と分岐は,パラログ間の競争的干渉につながる可能性があります.
- Mcm1における歴史的アミノ酸置換は,現存種のパラログ干渉を最小限に抑えた.
- パラログ干渉の解消により,Mcm1-調節遺伝子ネットワーク内の分子複雑性が増加しました.
結論:
- パラログ干渉は,重複した遺伝子の進化,特に複雑な組成に関与する遺伝子の進化に重大な制約を与える.
- パラログ干渉の解消は,より大きな規制の複雑性の進化を促すことができます.
- パラログ干渉を最小限に抑えることは,複製された遺伝子のゲノムへの安定した統合に不可欠です.
関連する概念動画
Gene Duplication and Divergence
The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
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Gene Families
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Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
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Combinatorial gene control is the synergistic action of several transcriptional factors to regulate the expression of a single gene. The absence of one or more of these factors may lead to a significant difference in the level of gene expression or repression.
The expression of more than 30,000 genes is controlled by approximately 2000-3000 transcription factors. This is possible because a single transcription factor can recognize more than one regulatory sequence. The specificity in gene...
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Transcriptional regulators bind to specific cis-regulatory sequences in the DNA to regulate gene transcription. These cis-regulatory sequences are very short, usually less than ten nucleotide pairs in length. The short length means that there is a high probability of the exact same sequence randomly occurring throughout the genome. Since regulators can also bind to groups of similar sequences, this further increases the chances of random binding. Transcriptional regulators form dimers that...
Cooperative Binding of Transcription Regulators
Transcriptional regulators bind to specific cis-regulatory sequences in the DNA to regulate gene transcription. These cis-regulatory sequences are very short, usually less than ten nucleotide pairs in length. The short length means that there is a high probability of the exact same sequence randomly occurring throughout the genome. Since regulators can also bind to groups of similar sequences, this further increases the chances of random binding. Transcriptional regulators form dimers that...
RNA Polymerase II Accessory Proteins
Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...

