プリオン認識要素は,核形成,株の特異性,種のバリアを制御する
Peter M Tessier1, Susan Lindquist
1Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, Massachusetts 02142, USA.
Nature
|May 15, 2007
まとめ
プリオンタンパク質の変換は,小さな配列要素によって正確に制御されます. これらの要素は,プリオン複製,菌株形成,種の伝播障壁を決定し,感染性タンパク質の構成に関する洞察を提供します.
科学分野:
- バイオケミストリー バイオケミストリー
- 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
背景:
- プリオンは自己永続的な形状を持つ感染性タンパク質ですが,その複製,株の多様性,および種間伝播は依然として十分に理解されていません.
- 溶液中のプリオンの振る舞いを調査することは,重大な複雑性をもたらします.
研究 の 目的:
- プリオン複製,菌株形成,種の伝播障壁を制御する分子機構を調査する.
- これらのプリオン特性を制御する特定の配列要素を特定する.
主な方法:
- プリオン行動の調査を簡素化するために,表面に結合したペプチドを使用した.
- 種間伝播を分析するためにキメリックSup35タンパク質を設計した.
主要な成果:
- プリオン状態へのスイッチを特定して制御する小型の一次配列要素を特定した.
- これらの同じ配列要素が,異なるプリオン株の形成と種特有の種蒔きの活動を支配することを実証しました.
- 菌株形成に対する環境的および変異的影響は,これらの配列要素の選択的認識によって引き起こされることを示した.
結論:
- プリオン変換,株の多様性,および伝播障壁は,タンパク質配列内の小さな特定の認識要素によって決定的に影響されます.
- これらの発見は,プリオン伝播と種間伝播の基本原理を明らかにします.
関連する概念動画
00:43Bacterial RNA Polymerase
20.0K
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...
20.0K
01:34Nuclear Protein Sorting
4.9K
Nuclear protein sorting is the selective trafficking of histones, polymerases, gene regulatory proteins into the nucleus and exporting RNAs and ribosomes to the cytosol. It is a tightly controlled process that regulates gene expression within a cell.
Proteins targeted to the nucleus carry nuclear localization signals or NLS recognized by import receptors in the cytosol. Similarly, proteins with nuclear export signals are recognized by export receptors. Import and export receptors are...
Proteins targeted to the nucleus carry nuclear localization signals or NLS recognized by import receptors in the cytosol. Similarly, proteins with nuclear export signals are recognized by export receptors. Import and export receptors are...
4.9K
01:45Regulation of Nuclear Protein Sorting
2.5K
Nuclear protein sorting regulates nucleus composition and gene expression, crucial for determining the fate of a eukaryotic cell. Hence, the entry and exit of molecules across the nuclear envelope is a tightly controlled process. Nuclear protein sorting can be inhibited by one of the following ways: 1) masking cargo signal sequences, 2) modifying the nuclear receptor's affinity for cargo, 3) controlling the nuclear pore size, 4) retaining the cargo during its transit to the cytosol or the...
2.5K
01:34Directing Proteins to the Rough Endoplasmic Reticulum
12.1K
The organelle-specific signaling sequences direct proteins synthesized in the cytosol to their final destination like ER, mitochondria, peroxisomes, etc. Some of the proteins directed to ER are then trafficked via vesicles to other organelles within the cell or the extracellular environment through the Golgi complex. For example, the rough ER synthesizes soluble proteins for transportation to the lysosomes or secretion out of the cell. It can also synthesize transmembrane proteins that can...
12.1K
01:24Nucleoid
2.3K
The nucleoid represents a structurally and functionally distinct region within prokaryotic cells, where the cell's DNA and associated proteins are housed. Unlike eukaryotic cells, prokaryotes lack a membrane-bound nucleus, and the nucleoid facilitates the organization and accessibility of the genetic material within this constraint. The DNA in most bacteria and archaea exists as a single, circular, double-stranded molecule that is highly compacted through supercoiling and interactions with...
2.3K
01:28Prokaryotic Gene Structure and Organization
2.9K
Prokaryotic genomes exhibit a streamlined organization of coding and non-coding regions essential for gene expression and protein synthesis. While coding regions contain the genetic instructions for proteins or functional RNAs, non-coding regions regulate the precise transcription and translation of these genes.Coding Regions: Proteins and RNAsThe primary coding regions, known as structural genes, include sequences transcribed into messenger RNA (mRNA) and ultimately translated into...
2.9K