インターキストロニックの幹ループ構造は,mRNAの衰退のターミネーターとして機能し, puf mRNAの安定性には必要だが不十分である
C Y Chen1, J T Beatty, S N Cohen
1Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts 02115.
Cell
|February 26, 1988
まとめ
R. capsulatus の重要なRNAヘアピンが,上流のpuf mRNAを安定させています. しかし,この構造だけでは,下流のmRNAを安定させることができず,分解終結剤としてのみ作用します.
科学分野:
- 微生物学 微生物学とは
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- R. capsulatus のポリシストロニクストランスクリプトは,セグメントの安定性差異を示し,光合成の遺伝子発現に影響を与えます.
- プフオペロントランスクリプトの5'端にある大きなインターシストロニックの幹ループ構造は,mRNAの安定性に関連しています.
研究 の 目的:
- プフオペロントランスクリプトの安定性におけるインターキストロン幹ループ構造の役割を調査する.
- ステム・ループ構造が安定剤か衰退終結剤として機能するかどうかを判断する.
主な方法:
- プフオペロントランスクリプトからインターシストロニックRNAヘアピンを削除.
- pufオペロントランスクリプトの3'端に茎ループ構造の挿入.
- エンドヌクレオリチス分裂とエクソリボヌクレアース活性を含むmRNA分解経路の分析.
主要な成果:
- RNAヘアピンを削除すると,5' puf mRNAセグメントが不安定になります.
- 3'端にヘアピンを挿入しても,ラビルの3' puf mRNAセグメントは安定しませんでした.
- 証拠によると,3'セグメントの崩壊は,幹ループとは独立して,エンドヌクレオリチス分裂で始まる.
結論:
- インターキストロニックRNAヘアピンは上流mRNAの安定化に不可欠ですが,それだけでは不十分です.
- RNAのヘアピンは,mRNAの崩壊のターミネーターとして機能し,3'-エクソリボ核酸から上流領域を保護します.
関連する概念動画
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RNA Stability
Intact DNA strands can be found in fossils, while scientists sometimes struggle to keep RNA intact under laboratory conditions. The structural variations between RNA and DNA underlie the differences in their stability and longevity. Because DNA is double-stranded, it is inherently more stable. The single-stranded structure of RNA is less stable but also more flexible and can form weak internal bonds. Additionally, most RNAs in the cell are relatively short, while DNA can be up to 250 million...
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Cis-acting Elements involved in mRNA stability
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Nonsense-mediated mRNA Decay
The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
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


