A PtdIns4,5P2-調節された核ポリ (A) ポリメラーゼは,選択されたmRNAの発現を制御する
David L Mellman1, Michael L Gonzales, Chunhua Song
1Program in Molecular and Cellular Pharmacology, University of Wisconsin Medical School, University of Wisconsin-Madison, 1300 University Avenue, Madison, Wisconsin 53706, USA.
Nature
|February 22, 2008
まとめ
核のフォスファディチリノシトール-4,5-ビスホスファート (PtdIns4,5P2) は,スター-PAPとの相互作用によって遺伝子発現を調節する. この脂質シグナル伝達分子はmRNAの3'-end形成を制御し,酸化ストレス反応遺伝子に影響を与えます.
科学分野:
- 分子生物学は分子生物学である.
- セルラー・シグナリング
- 遺伝子発現の規制について
背景:
- フォスフォノシチドは,真核細胞の細胞機能を調節する重要な脂質シグナル伝達分子である.
- フォスファディチルイノシトール-4,5-ビスホスファート (PtdIns4,5P2) は,I型フォスファディチルイノシトール4'-リン酸5-キナーゼ (PIPKI) によって生成されるフォスファディチルイノシトールシグナル伝達に中心的です.
- フォスホイノシチドは核内で機能するが,その直接的な調節機構は不明である.
研究 の 目的:
- 核機能の調節における核PtdIns4,5P2の役割を解明する.
- 核PIPK,PIPKIalpha.alphaと相互作用するタンパク質パートナーを特定するために.
主な方法:
- 核内のPIPKIアルファの局所化を決定するための共同局所化研究.
- タンパク質とタンパク質の相互作用測定は,PIPKIalpha.の結合パートナーを特定するために行われます.
- Star-PAP活動に対するPtdIns4,5P2の調節効果を評価するための生化学分析.
- PIPKIalpha-Star-PAP複合体によって調節される特定の遺伝子のmRNA 3'-end形成の分析.
主要な成果:
- PIPKIalphaは,Star-PAPと名付けられた,新しい非正規のポリ (A) ポリメラーゼと,核の斑点に同局する.
- Star-PAPの活動は,PtdIns4,5P2.2によって特に規制されています.
- PIPKIalpha-Star-PAP複合体は,mRNAの3'-end形成を調節することによって,ヘム酸素酶-1および他の酸化ストレス反応遺伝子を含む特定のmRNAの発現を制御する.
結論:
- 新しいメカニズムは,核のフォスホイノシチドシグナル伝達と遺伝子発現の調節の統合を明らかにします.
- PIPKIalphaとStar-PAPは,3'-end処理を通じてmRNA生物合成を調節する複合体を形成しています.
- この経路は,核内の脂質シグナル伝達が,酸化ストレス反応に関与する遺伝子などの重要な遺伝子の発現を制御する方法を強調しています.
関連する概念動画
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...
Regulation of Expression Occurs at Multiple Steps
Gene expression can be regulated at almost every step from gene to protein. Transcription is the step that is most commonly regulated. This involves the binding of proteins to short regulatory sequences on the DNA. This association can either promote or inhibit the transcription of a gene associated with the respective sequence.
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Regulated 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...
Regulation of Expression Occurs at Multiple Steps
Gene expression can be regulated at almost every step from gene to protein. Transcription is the step that is most commonly regulated. This involves the binding of proteins to short regulatory sequences on the DNA. This association can either promote or inhibit the transcription of a gene associated with the respective sequence.
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Regulated 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...
Regulation of Expression at Multiple Steps
The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. Transcriptional regulation is mediated by regulatory proteins such as transcription factors, activators, or repressors—these control gene expression by initiating or inhibiting the transcription of genes. Once a precursor or pre-mRNA is produced, it undergoes post-transcriptional modification, including 5' capping, splicing, and the addition of a...


