イーストRNAポリメラーゼIIは5A解像度で
J Fu1, A L Gnatt, D A Bushnell
1Department of Structural Biology, Stanford University School of Medicine, Fairchild Science Center, California 94305, USA.
Cell
|September 28, 1999
まとめ
研究者らはX線微分法を使用して,酵母RNAポリメラーゼIIの構造を決定した. これは,転写中にDNAとRNAのクランプとして作用する移動性タンパク質ドメインを明らかにした.
科学分野:
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
- 分子生物学は分子生物学である.
背景:
- 酵母RNAポリメラーゼIIは,遺伝子転写に不可欠です.
- その構造を理解することは,その機能を解読する鍵です.
研究 の 目的:
- イーストRNAポリメラーゼIIの高解像度構造を決定する.
- 転写における移動性タンパク質ドメインの機能的役割を明らかにする.
主な方法:
- 酵母RNAポリメラーゼII結晶の18重原子クラスター誘導体のX線 difraktion.
- 5A解像度で取得した相情報.
- 電子結晶学データとの比較.
主要な成果:
- 5A解像度に関する重要な段階の情報が得られた.
- A6A電子密度マップは,電子結晶学の16A分子封筒と密接に一致し,相を検証しました.
- 2つの移動タンパク質ドメインが特定されました:下流のDNAクランプと,トランスクリプトを囲むヒンジングのRNAクランプ.
結論:
- この研究は,酵母RNAポリメラーゼIIの機能に関する構造的な洞察を提供します.
- 移動性タンパク質ドメインは,転写中のDNA結合とRNA封じ込めにおいて重要な役割を果たします.
- この発見は,トランスクリプションの延長メカニズムについての理解を深める.
関連する概念動画
00:43Bacterial RNA Polymerase
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In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
00:58Eukaryotic RNA Polymerases
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All three eukaryotic RNAPs require specific transcription factors, of which the...
All three eukaryotic RNAPs require specific transcription factors, of which the...
02:36RNA 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...
00:43Bacterial RNA Polymerase
Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
00:58Eukaryotic RNA Polymerases
RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
All three eukaryotic RNAPs require specific transcription factors, of which the...
All three eukaryotic RNAPs require specific transcription factors, of which the...
02:36RNA 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...