エンドヌクレオリティックRNAは,真核生物のエクソソームによって分裂する
Alice Lebreton1, Rafal Tomecki, Andrzej Dziembowski
1Equipe Labellisée La Ligue, Centre de Génétique Moléculaire, CNRS UPR 2167, 91198 Gif-sur-Yvette, France.
Nature
|December 9, 2008
まとめ
重要なRNA処理装置であるエウカリオスのエクソソームは,エンドヌクレオリチスとエクソヌクレオリチスの両方の活動を持っています. Dis3サブユニットによって媒介されるこれらの二重機能は,細胞RNAの調節と生存に不可欠です.
科学分野:
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
- 遺伝学 遺伝学とは
背景:
- エクソソームは,RNAの処理,品質管理,およびターンオーバーに関与する重要な真核核酶です.
- 9つのサブユニットのリング構造を持つ3'から5'エクソヌクレアゼとして機能します.
- 以前の研究では,ユカリオットの無活性環構造が示され,活動性はDis3のRNBドメインにのみ属していた.
研究 の 目的:
- ユカリオットのエクソソーム核の触媒的活動を調査する.
- エクゾーム機能におけるDis3サブユニットのPINドメインの役割を決定する.
- RNAの代謝におけるエンド・およびエクソヌクレオリチス活動の組み合わせによる貢献を解明する.
主な方法:
- 酵素活性を評価するためのインビトロ測定法.
- 活性化されていないエクソソームコアドメインを持つ酵母菌株の分析.
- 特定の遺伝条件下で酵母菌の成長のフェノタイプ分析.
主要な成果:
- 酵母DIS3は,エンドロビヌクレアゼ (PIN領域) とエクソヌクレアゼ (RNB領域) の活動の両方を表しています.
- 両方の活動が同時に不活性化されると,生体内で合成成長障害が生じます.
- PINドメインの内核分解性活動は,外核分解性分解とは無関係に自然エクソソーム基板の分裂に寄与する.
結論:
- ユーカリオットのエクソソームコアには,EndとExonucleolyticの両方の活動があり,Dis3サブユニットの異なるドメインによって媒介されます.
- この発見は,エクソソーム機能の現在のモデルに異議を唱え,複数のリボ核分裂活動が協力することを強調しています.
- RNAの処理と分解におけるエクソソームの役割を再検討し,その二重の触媒的能力を組み込むことが正当化されています.
さらに関連する動画
06:10A Fluorescence-based Exonuclease Assay to Characterize DmWRNexo, Orthologue of Human Progeroid WRN Exonuclease, and Its Application to Other Nucleases
Published on: December 23, 2013
09:20Identification of RNA Fragments Resulting from Enzymatic Degradation using MALDI-TOF Mass Spectrometry
Published on: April 11, 2022
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...
Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
mRNA Stability and Gene Expression
The structure and stability of mRNA molecules regulates gene expression, as mRNAs are a key step in the pathway from gene to protein. In eukaryotes, the half-life of mRNA varies from a few minutes up to several days. mRNA stability is essential in growth and development. The absence of the proteins regulating its stability, such as tristetraprolin in mice, can cause systemic issues, including bone marrow overgrowth, inflammation, and autoimmunity.
Cis-acting Elements involved in mRNA stability
Cis-acting Elements involved in mRNA stability
Ribozymes
The term ribozyme is used for RNA that can act as an enzyme. Ribozymes are mainly found in selected viruses, bacteria, plant organelles, and lower eukaryotes. Ribozymes were first discovered in 1982 when Tom Cech’s laboratory observed Group I introns acting as enzymes. This was shortly followed by the discovery of another ribozyme, Ribonulcease P, by Sid Altman’s laboratory. Both Cech and Altman received the Nobel Prize in chemistry in 1989 for their work on ribozymes.
Ribozymes can be...
Ribozymes can be...
