スプライソソームのU4snRNPコアドメインの構造と,snRNPの生物発生に対するその影響
Adelaine K W Leung1, Kiyoshi Nagai, Jade Li
1MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, UK.
Nature
|April 26, 2011
まとめ
スプライセオソームは,
科学分野:
- 分子生物学は分子生物学である.
- 構造生物学 構造生物学とは
- バイオケミストリー バイオケミストリー
背景:
- スプライソームは,RNAのスプライシングに不可欠な分子装置である.
- 7 Smタンパク質は,U1,U2,U4,U5の小さな核リボヌクレオプロテイン (snRNP) の核を形成する.
- シトプラズマ内のsnRNAにSmタンパク質の組み立ては,snRNPの生物発生に不可欠です.
研究 の 目的:
- U4 snRNPコアドメインの結晶構造を決定する.
- SmサイトRNAとHeptameric Smタンパク質リングの相互作用を解明する.
- U4 snRNPの構造をU1 snRNPと比較して snRNPの成熟を把握する.
主な方法:
- 3.6 Åの解像度のX線結晶学で,U4 snRNPのコアドメイン構造を決定する.
- 既存のU1 snRNPデータ (5.5 Å解像度) との構造比較.
主要な成果:
- SmサイトRNA (AUUUUUG) とヘプタアメリカンSmタンパク質リング (SmE-SmG-SmD3-SmB-SmD1-SmD2-SmF) の間の詳細な原子相互作用.
- 結合には,不規則なRNAの骨格構造と非対称なタンパク質のリング構造が含まれています.
- U1 snRNPとの比較で,Sm折りの外で snRNAに依存する構造的変化が観察されました.
結論:
- 構造は,コア snRNP アセンブリの正確な分子機構を明らかにします.
- これらの相互作用を理解することで,スプライソームの組立と機能の洞察が得られます.
- 構造的変異は,snRNPの成熟過程における粒子特異タンパク質の結合の違いを説明する可能性がある.
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...
Ribosomal RNA Synthesis
Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Additional Subnuclear Structures
The eukaryotic nucleus is a double membrane-bound organelle that contains nearly all of the cell’s genetic material in the form of chromosomes. It is rightly called the “brain” of the cell as it shoulders the responsibility of responding to various physiological processes, stress, altered metabolic conditions, and other cellular signals.
The nucleus contains many membrane-less subnuclear organelles or nuclear bodies, such as nucleoli, Cajal bodies, speckles, paraspeckles, etc. These nuclear...
The nucleus contains many membrane-less subnuclear organelles or nuclear bodies, such as nucleoli, Cajal bodies, speckles, paraspeckles, etc. These nuclear...
Chromatin Structure and RNA Splicing
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...
Ribosomal RNA Synthesis
Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...


