ポリソームとサイトプラズマ的処理体間のエウカリオスのmRNAの移動
Muriel Brengues1, Daniela Teixeira, Roy Parker
1Department of Molecular and Cellular Biology and Howard Hughes Medical Institute, University of Arizona, Tucson, AZ 85721-0106, USA.
Science (New York, N.Y.)
|September 6, 2005
まとめ
酵母P体内のメッセンジャーRNA (mRNA) は,単に分解されるのではなく,翻訳を再入力することができます. この発見は,細胞の調節に不可欠なダイナミックなmRNAリサイクル経路を明らかにしています.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- イースト遺伝学 イースト遺伝学
背景:
- ユカリオット細胞は,非翻訳伝達 RNA (mRNA) を処理体 (P体) に貯蔵する.
- P-ボディは,伝統的にmRNAの断片と分解の場所として見られています.
研究 の 目的:
- 酵母P体内のmRNAのダイナミックな行動を調査する.
- mRNA分子がP体から翻訳に戻ることができるかどうかを判断する.
主な方法:
- 新しいmRNAがP体へ伝達されるのを阻害する.
- ストレス回復中のP-bodyダイナミクスの観察.
- レポーターmRNAの局所化と翻訳の分析.
- 静止相酵母におけるP-ボディの検査.
主要な成果:
- P-ボディの分解は,新しいmRNAの配送がブロックされたとき,mRNAの分解とは独立して発生します.
- ストレス回復中のP体減少は,翻訳開始に依存する.
- レポーターmRNAは,翻訳が阻害されたときにP体内に蓄積し,復元時に翻訳を再開します.
- 静止相酵母P体には,成長再開時に翻訳を再開するmRNAが含まれています.
結論:
- 酵母P体は,mRNAが翻訳に戻ることを促進するダイナミックなハブです.
- ポリソームとP体間の相互的なmRNAの動きは,翻訳制御に不可欠である.
- このmRNA貯蔵とリサイクルメカニズムは,保存され,広く適応されている可能性が高い.
関連する概念動画
02:01pre-mRNA Processing
In eukaryotic cells, transcripts made by RNA polymerase are modified and processed before exiting the nucleus. Unprocessed RNA is called precursor mRNA or pre-mRNA to distinguish it from mature mRNA.
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl guanosine). This 5’ cap helps the...
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl guanosine). This 5’ cap helps the...
02:01Pre-mRNA Processing
In eukaryotic cells, transcripts made by RNA polymerase are modified and processed before exiting the nucleus. Unprocessed RNA is called precursor mRNA or pre-mRNA to distinguish it from mature mRNA.
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl guanosine). This 5’ cap helps the...
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl guanosine). This 5’ cap helps the...
02:31Nuclear 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...
02:22Regulated mRNA Transport
In eukaryotes, transcription and translation are compartmentalized; an mRNA is first synthesized in the nucleus and then selectively transported to the cytoplasm for protein synthesis. Before transport, a pre-mRNA undergoes several steps of post-transcriptional modifications including splicing, 5' capping, and the addition of a poly-adenine tail. Various proteins bind to the pre-mRNA during these modifications. The mRNA transport takes place with the help of multiple proteins playing specific...
02:31Nuclear 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...
02:22Regulated mRNA Transport
In eukaryotes, transcription and translation are compartmentalized; an mRNA is first synthesized in the nucleus and then selectively transported to the cytoplasm for protein synthesis. Before transport, a pre-mRNA undergoes several steps of post-transcriptional modifications including splicing, 5' capping, and the addition of a poly-adenine tail. Various proteins bind to the pre-mRNA during these modifications. The mRNA transport takes place with the help of multiple proteins playing specific...