分子決定因子と種特有のRNA編集の導かれた進化
1Department of Genetics and Developmental Biology, University of Connecticut Health Center, Farmington, Connecticut 06030, USA. rreenan@neuron.uchc.edu
Nature
|March 18, 2005
まとめ
シナプトタグミンI (sytI) のアデノシンからイノシンへのRNA編集は,種特有の有意な変化を示しています. 新規の擬似結び目を含む複雑な内部RNA構造は,ヘキサポッドの進化を通じてこれらの編集パターンを決定する.
科学分野:
- 分子生物学は分子生物学である.
- 進化生物学の進化生物学について
- ゲノミクスゲノミクスとは
背景:
- RNA編集は,真核生物において機械的に多様である.
- アデノシンからイノシン (A-to-I) のRNA編集は,動物ではよく見られ,しばしば保存されたタンパク質コードの位置を変更する.
- シナプトタグミンI (sytI) の再コーディングは,種間の顕著な違いを示しています.
研究 の 目的:
- シナプトタグミンI (sytI) のRNA編集における種特有の変異を調査する.
- sytI RNA編集を統制する規制メカニズムを特定する.
- Sytil遺伝子編集の進化史を理解するために.
主な方法:
- 34種のゲノムを比較した.
- RNA構造の変異分析.
- シティル遺伝子編集の系統遺伝分析.
主要な成果:
- sytI編集サイトの有意な変動は種ごとに観察され,一部のサイトは共有され,他のサイトはユニークでした.
- ミツバチ,甲虫,ゴキブリはシチラ編集をしない.
- 新しい長距離シドノットを含む,イントロン内の複雑な,マルチドメインのプレ-mRNA構造は,種特有の編集の重要な決定因子として特定されました.
- 小さな内部配列の変化は,RNA基板間の編集特異性を変化させる可能性があります.
- ヘクサポッドの進化の2億5000万年以上に及ぶシティル遺伝子編集の系統系が支持されました.
結論:
- sytIの種別RNA編集は,主に複雑な内部RNA構造によって決定されます.
- これらの発見は,RNA編集サイトの進化のモデルを提供します.
- この研究は,ヘクサポッドにおけるシティルRNA編集の進化の軌道を明らかにしている.
関連する概念動画
RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
Chromatin Structure Regulates pre-mRNA Processing
In eukaryotic cells, nascent mRNA transcripts need to undergo many post-transcriptional modifications to reach the cell cytoplasm and translate into functional proteins. For a long time, transcription and pre-mRNA processing were considered two independent events that occur sequentially in the cell. However, it has now been well established that transcription and pre-mRNA processing are two simultaneous processes that are precisely regulated inside the cell.
The chromatin structure, especially...
The chromatin structure, especially...
Alternative RNA Splicing
Alternative RNA splicing is the regulated splicing of exons and introns to produce different mature mRNAs from a single pre-mRNA. Unlike in constitutive splicing where a single gene produces a single type of mRNA, alternative splicing allows an organism to produce multiple proteins from a single gene and plays an important role in protein diversity.
There are five types of alternative RNA splicing that vary in the ways the pre-mRNA segments are removed or retained in the mature mRNA. The first...
There are five types of alternative RNA splicing that vary in the ways the pre-mRNA segments are removed or retained in the mature mRNA. The first...
RNA Editing
RNA editing is a post-transcriptional modification where a precursor mRNA (pre-mRNA) nucleotide sequence is changed by base insertion, deletion, or modification. The extent of RNA editing varies from a few hundred bases, in mitochondrial DNA of trypanosomes, to a just single base, in nuclear genes of mammals. Even a single base change in the pre-mRNA can convert a codon for one amino acid into the codon for another amino acid or a stop codon. This type of re-coding can significantly affect the...
Regulation of Expression at Multiple Steps
The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. Transcriptional regulation is mediated by regulatory proteins such as transcription factors, activators, or repressors—these control gene expression by initiating or inhibiting the transcription of genes. Once a precursor or pre-mRNA is produced, it undergoes post-transcriptional modification, including 5' capping, splicing, and the addition of a...


