集まったステレオシリア間の力は,サブナノメートルのスケールで耳の摩擦を最小限にします
Andrei S Kozlov1, Johannes Baumgart, Thomas Risler
1Howard Hughes Medical Institute and Laboratory of Sensory Neuroscience, The Rockefeller University, 1230 York Avenue, New York, New York 10065, USA.
Nature
|May 24, 2011
まとめ
耳 耳は耳です.
科学分野:
- 聴覚科学とは,聴覚に関する科学です.
- バイオフィジックス 生物物理学
- 機械生物学のメカノバイオロジー
背景:
- 音の検出は,毛細胞のステレオシリアの動きに依存しています.
- 髪の束の粘着性の摩擦は,聴覚の感度と周波数選択性に挑戦します.
- 活性増幅プロセスは,この課題を部分的に解決します.
研究 の 目的:
- 髪の束の内にある粘着摩擦を和らげるために,流体構造相互作用の役割を調査する.
- 音に誘発された運動中のステレオシリア間の力を特徴付ける.
- ヘアバンドル構造がメカニカル伝導を最適化する方法を解明する.
主な方法:
- スケールモデルでの力測定.
- 有限要素分析と水力力学的力の推定.
- ストキャスティックシミュレーションと高解像度インターフェロメトリック測定.
- チャネルゲーティングによる歪み産物の分析.
主要な成果:
- ステレオシリアの密着した位置は,ステレオシリア間の液体を固定し,抵抗を軽減します.
- 流体構造の相互作用は圧縮する動きを抑制するが,滑動する動きは抑制しない.
- 尖端リンクとトップコネクタは,さらに抵抗を軽減し,構造を安定させます.
- ステレオシリア間の相対的な動きは,ナノメートルのほんの一部分に限定されます.
結論:
- ステレオシリアの配置と結合タンパク質を含む,髪の束の構造的特徴は,粘着性の抵抗を最小限に抑えます.
- 液体構造の相互作用は,敏感で選択的な聴覚メカニカル伝導に不可欠です.
- 髪の束を制御する物理的原理は,効率的な信号検出のために適応されています.
関連する概念動画
Hair 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.
The Cochlea
The cochlea is a coiled structure in the inner ear that contains hair cells—the sensory receptors of the auditory system. Sound waves are transmitted to the cochlea by small bones attached to the eardrum called the ossicles, which vibrate the oval window that leads to the inner ear. This causes fluid in the chambers of the cochlea to move, vibrating the basilar membrane.
Mechanism of Ciliary Motion
The ciliary structures were first seen in 1647 by Antonie Leeuwenhoek while observing the protozoans. In lower organisms, these appendages are responsible for cell movement, while in higher organisms, these appendages help in the movement of the extracellular fluids within the body cavities.
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
Mechanism of Ciliary Motion
The ciliary structures were first seen in 1647 by Antonie Leeuwenhoek while observing the protozoans. In lower organisms, these appendages are responsible for cell movement, while in higher organisms, these appendages help in the movement of the extracellular fluids within the body cavities.
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
Frictional Force
When a body is in motion, it encounters resistance because the body interacts with its surroundings. This resistance is known as friction, a common yet complex force whose behavior is still not completely understood. Friction opposes relative motion between systems in contact, but also allows us to move. Friction arises in part due to the roughness of surfaces in contact. For one object to move along a surface, it must rise to where the peaks of the surface can skip along the bottom of the...
Equilibrium and Balance
The inner ear assumes dual functionalities of auditory perception and equilibrium maintenance. The vestibule is the organ responsible for balance. This organ contains mechanoreceptors, specifically hair cells, endowed with stereocilia, which aid in deciphering information regarding the position and motion of our heads. Two intrinsic components, the utricle and saccule, help perceive head position, while the semicircular canals track head movement. Neurological messages initiated in the...


