Ro-sieの周りのリング:RNA媒介によるPNP酵素活性の変化
Brian J Geiss1, Jeffrey Wilusz
1Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA. brian.geiss@colostate.edu
Cell
|April 2, 2013
まとめ
非コーディングRNAは,複雑な細胞機構を調節することができる. この研究では,特定のノンコーディングRNAが,エクソリボニュクレアース酵素をどのように変化させるかを示しています.
科学分野:
- 分子生物学は分子生物学である.
- RNAの生物学とは,RNAの生物学である.
- 酵素学 酵素学とは
背景:
- ノンコーディングRNA (ncRNA) は,遺伝子調節において重要な役割を果たします.
- 多成分複合体は,細胞機能に不可欠である.
- エクソリボヌクレアゼは,RNA分子を分解する酵素です.
研究 の 目的:
- 非コーディングRNAが多成分複合体の機能を調節する新しいメカニズムを解明する.
- 非コーディングRNAとエクソリボヌクレアゼの間の特定の相互作用を調査する.
- この相互作用がエクソリボンucleaseの活性と基板特異性にどのように影響するかを決定する.
主な方法:
- RNAとタンパク質の相互作用を研究するための生化学分析.
- 酵素活性アッセイは,エクソリボヌクレアゼの機能を測定する.
- リボ核タンパク質複合体の形成を理解するための構造分析.
主要な成果:
- 特定のノンコーディングRNAがエクソリボヌクレアゼと相互作用することが判明した.
- この相互作用は,エクソリボヌクレアゼの基板特異性を変化させます.
- 非コーディングRNAは,リボヌクレオプロテインの支架として作用し,潜在的に基板へのアクセスを制御します.
結論:
- 非コーディングRNAは,タンパク質複合体の酵素活性と基板標的を直接調節することができます.
- このncRNA-エクソヌクレアゼ相互作用は,酵素機能のncRNA媒介調節のための新しいモデルを提供します.
- この発見は,細胞の調節におけるncRNAの汎用性を強調しています.
関連する概念動画
piRNA - Piwi-interacting RNAs
PIWI-interacting RNAs, or piRNAs, are the most abundant short non-coding RNAs. More than 20,000 genes have been found in humans that code for piRNAs while only 2000 genes have been found for miRNAs. piRNAs can act at the transcriptional and post-transcriptional levels and have a vital role in silencing transposable elements present in germ cells. They are also involved in epigenetic silencing and activation. Previously, they were thought to function only in germ cells but new evidence suggests...
RNA Editing
RNA editing is a post-transcriptional modification where a precursor mRNA (pre-mRNA) nucleotide sequence is changed by base insertion, deletion, or modification. The extent of RNA editing varies from a few hundred bases, in mitochondrial DNA of trypanosomes, to a just single base, in nuclear genes of mammals. Even a single base change in the pre-mRNA can convert a codon for one amino acid into the codon for another amino acid or a stop codon. This type of re-coding can significantly affect the...
Biosynthesis of Nucleic Acids
Nucleic acid biosynthesis is a fundamental biochemical process that produces the purine and pyrimidine nucleotides essential for DNA and RNA synthesis. This pathway maintains a balanced nucleotide pool, preventing imbalances that could jeopardize genetic integrity and cellular function. Given the crucial role of nucleotides, their synthesis is tightly regulated to ensure proper cellular homeostasis.Purine BiosynthesisThe biosynthesis of purine nucleotides begins with ribose-5-phosphate, a...
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,...
Chromatin Structure Regulates pre-mRNA Processing
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...
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...

