コンドリキシアンの音響ヘッジホッグの機能と付属体のパターンの進化
Randall D Dahn1, Marcus C Davis, William N Pappano
1Department of Organismal Biology and Anatomy, The University of Chicago, Chicago, Illinois 60637, USA.
Nature
|December 26, 2006
まとめ
ソニック・ヘッジホッグ (Shh) 遺伝子調節は,脊椎動物のペア付属の進化において深く保存されています. コンドリヒチアンは,線羽魚や四足動物とShh表現と機能パターンを共有し,保存された遺伝的メカニズムを明らかにしています.
科学分野:
- 進化的発達生物学 進化的発達生物学
- 比較ゲノミクスとは
- 脊椎動物の古生物学について
背景:
- テトラポッドの四肢の発達遺伝子は知られているが,進化の組み立てと基礎脊椎動物の機能は不明である.
- ペアリングされた付属体の原始的脊椎動物であるコンドリヒチアンは,ソニック・ヘッジホッグ (Shh) による独立付属体の骨格パターンを有すると考えられていた.
- これは,線羽魚や四足類と対照的であり,異なる進化の経路を示唆しています.
研究 の 目的:
- 基礎脊椎動物におけるソニック・ヘッジホッグ (Shh) 遺伝子機能の進化的保存を調査する.
- コンドリクシアンの付属体の発達におけるShhの役割とその進化的意味を説明する.
- 主要な脊椎動物の系統におけるShh調節を比較する.
主な方法:
- コンドリヒチアにおけるShh遺伝子発現パターンの比較分析.
- Shh 付属体特有の規制DNA要素の識別と特徴付け.
- 附属体のパターニングにおけるShhの役割を評価する機能的研究.
主要な成果:
- コンドリヒチアンは,付属体の保存されたパターンを示しています. Shh表現.
- 類似したSHH付属体特異的な調節DNA配列は,コンドリクシアン,光魚,四足類にも確認された.
- 証拠によると,Shhは,コンドリクシアンの付属体のパターニングに保存された機能的な役割を果たしていることを示唆しています.
結論:
- 付属体の発達におけるソニック・ヘッジホッグ (Shh) 機能は,脊椎動物の系統系全体で深く保存されています.
- Shhの規制メカニズムの進化は,付属体の進化の間に主要な形態学的変化に寄与した可能性が高い.
- コンドリヒチアンは,他のの脊椎動物と基本的なShh依存型パターニングメカニズムを共有しています.
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.
01:13The 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.
01:17Characteristics of OpAmp
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01:16Characteristics of Practical Op Amps
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01:25Instrumentation Amplifier
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01:23Design Example
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