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Updated: Aug 12, 2026
11:35
Flash Photolysis of Caged Compounds in the Cilia of Olfactory Sensory Neurons
Published on: October 29, 2011
嗅覚受容体細胞のカルシウム依存塩化物チャンネルによる非線形増幅
Nature
|November 18, 1993
まとめ
哺乳類の嗅覚受容体細胞は,匂いを検知するために循環核酸ゲートチャネルを使用します. クロライドの電流は,匂いの信号を放大し,反応を高め,匂いの差別を改善します.
科学分野:
- 嗅覚神経科学とは
- 哺乳類の感覚システムは,
- 分子生物学は分子生物学である.
背景:
- 哺乳類の嗅覚は,高感度で多数の匂いを区別することを可能にします.
- 哺乳類における匂い誘発性膜電流の正確なメカニズムは不明である.
- 両生類の嗅覚伝導は,周期性核酸ゲートチャネルと塩化物流を含む.
研究 の 目的:
- 哺乳類の嗅覚受容体細胞における臭味誘発性膜電流を解明する.
- 哺乳類の嗅覚伝導における塩化物流の役割を調査する.
- 哺乳類と両生類の嗅覚伝導機構を比較する.
主な方法:
- ネズミの嗅覚受容体細胞からの電気生理学的記録.
- サイクル・ヌクレオチド・ゲート・チャネル活動の分析.
- 細胞内塩化物濃度と電流の測定.
主要な成果:
- ネズミの嗅覚受容体細胞における匂い変換は,周期性核酸ゲートチャネルによって開始されます.
- 塩化物流はネズミの嗅覚受容体細胞に存在し,両生類に似ている.
- クロライド電流は,周期的なAMP濃度に対するシグモイド的依存性を与え,伝導信号を放大します.
結論:
- サイクリックヌクレオチドゲートチャネルは,哺乳類における嗅覚伝導の主要なイニシアターである.
- クロライド電流は,哺乳類と両生類の両方で嗅覚信号を放大する上で重要な役割を果たします.
- この増幅メカニズムは,ベースノイズより上位の超値応答を刺激することによって,匂いの差別を高めます.
関連する概念動画
01:22Hair Cells
Hair cells are the sensory receptors of the auditory system—they transduce mechanical sound waves into electrical energy that the nervous system can understand. Hair cells are located in the organ of Corti within the cochlea of the inner ear, between the basilar and tectorial membranes. The actual sensory receptors are called inner hair cells. The outer hair cells serve other functions, such as sound amplification in the cochlea, and are not discussed in detail here.
01:11Channel Rhodopsins
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01:15Amplifying Signals via Second Messengers
Many receptor binding ligands are hydrophilic; they do not cross the cell membrane but bind to cell-surface receptors. Thus, their message must be relayed by second messengers present in the cell cytoplasm. There are several second messenger pathways, each with its own way of relaying information. For example, the G protein-coupled receptors can activate both phosphoinositol and cyclic AMP (cAMP) second messenger pathways. The phosphoinositol pathway is active when the receptor induces...
01:21G-Protein Gated Ion Channels
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Sensory organs,...
Sensory organs,...
01:27Feedback Regulation of Calcium Concentration
Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
01:16Calmodulin-dependent Signaling
Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...