アデノウイルスメジャー・ラット・トランスクリプション・ユニットからのトランスクリプトの早期キャッピング
Nature
|September 18, 1980
まとめ
RNAキャピングは,アデノウイルス2型 (Ad-2) RNA処理の初期のイベントであり,転写開始直後に急速に発生します. これは,RNAキャピングがすべてのRNAポリメラーゼII産物の自動プロセスであり,mRNA成熟の選択的なステップではないことを示唆しています.
科学分野:
- 分子生物学は分子生物学である.
- ウイルス学 ウイルス学 ウイルス学
- 遺伝子発現の表現について
背景:
- 転写後の改変は,RNA処理に不可欠である.
- これらの変更の時間順は,トランスクリプトの運命に影響を与える可能性があります.
- RNAキャピングは,真核生物の遺伝子発現における重要な改変である.
研究 の 目的:
- RNAの修飾の時間的な順序を調査するために.
- RNA処理における5'キャップ形成の役割を決定する.
- アデノウイルス2型 (Ad-2) 核RNAのキャピングのタイミングを検証する.
主な方法:
- アデノウイルス2型 (Ad-2) 核RNAの分析.
- 3H-アデノシンのRNAへの組み込みを追跡する.
- RNAポリメラーゼIIのトランスクリプション製品の研究.
主要な成果:
- 5'キャップ形成はAd-2核RNA処理の初期段階である.
- 3H-アデノシンは,キャップと初期RNA鎖の両方に急速に侵入します.
- 証拠によると,キャピングはmRNA処理の選択的なステップではないことを示唆しています.
結論:
- RNAカッピングは,すべてのRNAポリメラーゼII産物にとって自動的に起こる現象であるようです.
- ケーピングは,RNA処理の成功において差異的な役割を果たさない可能性が高い.
- この発見は,一般的なmRNA代謝を理解するための意味を持つ.
関連する概念動画
pre-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...
Transcription Attenuation in Prokaryotes
Transcriptional attenuation occurs when RNA transcription is prematurely terminated due to the formation of a terminator mRNA hairpin structure. Bacteria use these hairpins to regulate the transcription process and control the synthesis of several amino acids including histidine, lysine, threonine, and phenylalanine. Transcription attenuation takes place in the non-coding regions of mRNA.
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
Leaky Scanning
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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
Bacterial Transcription
RNA polymerase (RNAP) carries out DNA-dependent RNA synthesis in both bacteria and eukaryotes. Bacteria do not have a membrane-bound nucleus. So, transcription and translation occur simultaneously, on the same DNA template.
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Pre-mRNA Processing: Modification of pre-mRNA Ends
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 (7-methyl guanosine). This 5' cap helps the cell...
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 (7-methyl guanosine). This 5' cap helps the cell...


