エッセンシャルイーストリボソームタンパク質の遺伝子アクティベーターIfh1の成長制御による募集
Stephan B Schawalder1, Mehdi Kabani, Isabelle Howald
1Department of Molecular Biology and NCCR Program Frontiers in Genetics University of Geneva, Sciences III, 30, quai Ernest-Ansermet, Geneva 4, CH-1211, Switzerland.
Nature
|December 24, 2004
まとめ
エッセンシャルタンパク質Ifh1は,最適な成長下で酵母におけるリボソームタンパク質 (RP) 遺伝子プロモーターを活性化させます. Ifh1結合はFhl1によって調節され,ストレス中に減少し,細胞成長制御に影響を与えます.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- イースト遺伝学 イースト遺伝学
背景:
- リボソーム生物生成は,細胞成長制御に不可欠です.
- リボソームタンパク質 (RP) 遺伝子は酵母で高度に転写されるが,ストレス中にダウンレギュレーションされる.
- TORのようなシグナル伝達経路は,RP遺伝子転写を調節しますが,開始制御は不明です.
研究 の 目的:
- Saccharomyces cerevisiaeにおけるRP遺伝子発現の調節を調査する.
- 様々な条件下でRP遺伝子転写の制御に関与する重要なタンパク質を特定する.
主な方法:
- RP遺伝子プロモーターへのタンパク質結合を評価するためのクロマチン免疫プレシピテーション.
- Ifh1とFhl1の相互作用と採用の分析.
- TOR阻害,栄養素の枯渇,飢餓の条件下でRP遺伝子調節を研究する.
主要な成果:
- エッセンシャルタンパク質Ifh1は,酵母における多くのRP遺伝子プロモーターと結合し,活性化させます.
- Ifh1は,Fhl1のフォークヘッド関連ドメイン経由でRP遺伝子プロモーターに勧誘される.
- Ifh1結合は,TOR阻害および栄養素の枯渇の間に減少し,飢餓の解放時に回復します.
結論:
- Ifh1は,最適な成長条件下でのRP遺伝子プロモーターの活性化に中心的な役割を果たします.
- Fhl1は,RP遺伝子プロモーターにIfh1の勧誘を媒介する.
- Ifh1とFhl1はRP遺伝子発現の重要なレギュレータであり,環境のシグナルをリボソーム生物発生と結びつける.
関連する概念動画
01:28Yeast Signaling
Yeasts are single-celled organisms, but unlike bacteria, they are eukaryotes (cells with a nucleus). Cell signaling in yeast is similar to signaling in other eukaryotic cells. A ligand, such as a protein or a small molecule released from a yeast cell, attaches to a receptor on the cell surface. The binding stimulates second-messenger kinases to activate or inactivate transcription factors that further regulate gene expression. Many of the yeast intracellular signaling cascades have similar...
02:35Transcription Elongation Factors
Transcription elongation is a dynamic process that alters depending upon the sequence heterogeneity of the DNA being transcribed. Hence, it is not surprising that the elongation complex's composition also varies along the way while transcribing a gene.
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
01:58Prokaryotic Transcriptional Activators and Repressors
The organization of prokaryotic genes in their genome is notably different from that of eukaryotes. Prokaryotic genes are organized, such that the genes for proteins involved in the same biochemical process or function are located together in groups. This group of genes, along with their regulatory elements, are collectively known as an operon. The functional genes in an operon are transcribed together to give a single strand of mRNA known as polycistronic mRNA.
Transcription of prokaryotic...
Transcription of prokaryotic...
02:36Cells Coordinate Growth and Proliferation
Cell size is a significant factor impacting cellular design, function, and fitness. There exists some internal coordination by which cells double their masses before division, thus, achieving homeostasis. Coordination between cell growth and proliferation depends on the checkpoints in between cell cycle phases. Loss of coordination or failure in the checkpoint mechanism can drive the cell to uncontrolled growth and loss of cellular function. Like dividing cells that coordinate cellular growth,...
01:58Prokaryotic Transcriptional Activators and Repressors
The organization of prokaryotic genes in their genome is notably different from that of eukaryotes. Prokaryotic genes are organized, such that the genes for proteins involved in the same biochemical process or function are located together in groups. This group of genes, along with their regulatory elements, are collectively known as an operon. The functional genes in an operon are transcribed together to give a single strand of mRNA known as polycistronic mRNA.
Transcription of prokaryotic...
Transcription of prokaryotic...
01:17Gene Regulation During Sporulation
Sporulation is a complex developmental process that allows certain Gram-positive bacteria, such as Bacillus subtilis and Clostridium species, to survive extreme environmental conditions. This process is tightly regulated by a series of signaling cascades and transcriptional controls, ensuring the formation of a highly resistant endospore.Sporulation is triggered by unfavorable conditions, such as nutrient depletion, and is governed by a phosphorelay system. One of the sensor kinases, such as...