Rafは,Sevenless信号伝導経路でRas1の下流で機能する
B Dickson1, F Sprenger, D Morrison
1Zoologisches Institut, Universität Zürich, Switzerland.
Nature
|December 10, 1992
まとめ
ドロソフィラララフのセリン/スレオニンキナーゼは,セブンレス (Sevenless) 経路のシグナル伝達に不可欠であり,R7細胞の運命決定を制御する. 遺伝学的研究は,この発達経路において,RafはRas1の下流とSinaの上流に作用することを確認しています.
科学分野:
- 発達生物学 発達生物学について
- 細胞シグナル伝達 細胞信号伝達
- 遺伝学 遺伝学とは
背景:
- ドロソフィラの眼の発達におけるR7細胞運命の仕様は,セブンレス (Sev) 受容体チロシンキナーゼ経路に依存しています.
- 識別された重要な信号構成要素には, Ras1, Sos, Gap1, sina が含まれ,細胞内信号伝送を媒介する.
- 哺乳類のRaf-1と同型であるドロソフィラララフのセリン/スレオニンキナーゼは,受容体チロシンキナーゼシグナル伝達に関与しています.
研究 の 目的:
- セブンレス (Sev) 信号伝達経路におけるドロソフィラララフセリン/スレオニンキナーゼの役割を調査する.
- R7 細胞運命を特定するために,細胞内信号伝導カスケード内の Raf の位置を決定します.
主な方法:
- ドロソフィラ・メラノガスターのラフ・ローカスの遺伝子解析.
- 構成的に活性化されたRafタンパク質を用いた機能的研究.
- 遺伝子エピスタシスは,信号構成要素の順序を決定する実験である.
主要な成果:
- R7細胞の発達におけるSev活性に対する反応は,RAFの機能に依存する.
- 構成的に活性化されたRafタンパク質は,Sevから独立してR7細胞の発達を誘導することができる.
- 遺伝的証拠は,Ras1の下流とSinaの上流でRafをシグナリングカスケードに配置しています.
結論:
- ドロソフィラララフのセリン/スレオニンキナーゼは,Sev媒介のR7細胞運命を決定する経路において重要な役割を果たします.
- Rafは重要な細胞内シグナル伝達分子として機能し,Ras1の下流とSinaの上流に作用する.
- これらの発見は,発達の文脈における受容体チロシンキナーゼシグナル伝達の基礎となる分子機構を明らかにします.
さらに関連する動画
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06:44Bioluminescence Resonance Energy Transfer (BRET)-Based Assay for Measuring Interactions of CRAF with 14-3-3 Proteins in Live Cells
Published on: March 1, 2024
関連する概念動画
The Ras Gene
The Ras-gene-encoded proteins are regulators of signaling pathways controlling cell proliferation, differentiation, or cell survival. The Ras-gene family in humans constitutes three primary members—the HRas, NRas, and KRas. These genes code for four functionally distinct yet closely related proteins—the HRas, NRas, KRas4A, and KRas4B. The involvement of mutant Ras genes in human cancer was first discovered in 1982 and is among the most common causes of human tumorigenesis.
Ras is a superfamily...
Ras is a superfamily...
Rab Cascades
Rab GTPases act in a regulated cascade during membrane fusion, helping the lipid bilayers mix. The Rab family of proteins are active when bound to GTP, and inactive when bound to GDP. Hence, they act as guanine nucleotide-dependent molecular switches. Rab-GTP recognizes and binds to long or short-range tethering proteins to capture the target vesicle. These tethers coordinate with SNAREs on the vesicle and the target membrane to assemble the trans SNARE complex that locks the mixing bilayers.
Interactions Between Signaling Pathways
Signaling cascades usually lack linearity. Multiple pathways interact and regulate one another, allowing cells to integrate and respond to diverse environmental stimuli.
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
Small GTPases - Ras and Rho
Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:
Three regulatory proteins control their activity:
MAPK Signaling Cascades
Mitogen-activated protein kinase, or MAPK pathway, activates three sequential kinases to regulate cellular responses such as proliferation, differentiation, survival, and apoptosis. The canonical MAPK pathway starts with a mitogen or growth factor binding to an RTK. The activated RTKs stimulate Ras, which recruits Raf or MAP3 Kinase (MAPKKK), the first kinase of the MAPK signaling cascade. Raf further phosphorylates and activates MEK or MAP2 Kinases (MAPKK), which in turn phosphorylates MAP...
The Ras Gene
The Ras-gene-encoded proteins are regulators of signaling pathways controlling cell proliferation, differentiation, or cell survival. The Ras-gene family in humans constitutes three primary members—the HRas, NRas, and KRas. These genes code for four functionally distinct yet closely related proteins—the HRas, NRas, KRas4A, and KRas4B. The involvement of mutant Ras genes in human cancer was first discovered in 1982 and is among the most common causes of human tumorigenesis.
Ras is a superfamily...
Ras is a superfamily...
