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原始的な細胞のための原始的な酵素:Giardiaの発現に必要なプロテアゼ
W Ward1, L Alvarado, N D Rawlings
1Department of Pathology, University of California, San Francisco 94143, USA.
Cell
|May 2, 1997
まとめ
研究者らは,Giardia寄生虫の感染に不可欠なシステインプロテアスを特定しました. このGiardiaプロテアゼは,原始的なキャセプシンBであり,真核生物の歴史の初期に進化し,酵素ファミリーの多様性を強調しました.
科学分野:
- 寄生虫学とは,寄生虫学である.
- 分子生物学は分子生物学である.
- 進化生物学の進化生物学について
背景:
- Giardiaの寄生虫は,初期のエウカリオット系統を表しています.
- トロフォゾイトがキスタから出てきて,感染を誘発する.
- システインプロテアゼ阻害剤は,ギアルディアの発症を阻害する.
研究 の 目的:
- Giardia excystation. に関する特定のシステインプロテアスを特定します.
- このプロテアゼの進化的起源と機能を決定する.
主な方法:
- 標的タンパク質酶を特定するために,バイオチニル化阻害剤を使用した.
- 特定されたプロテアゼをコードする遺伝子をクローン化しました.
- 顕微鏡を用いてGiardia細胞内のプロテアゼを局所化しました.
主要な成果:
- エクシステーションに不可欠な新しいシステインプロテアスを特定し,クローン化しました.
- エクシーステーション直前に放出された膀にプロテアゼを局所しました.
- 系統遺伝学的分析により,このプロテアゼが,知られている最も古いカテプシンBであることが明らかになった.
結論:
- Giardiaのシステインプロテアゼは,寄生虫感染症の発生に重要な役割を果たします.
- キャセプシンB系は,植物と動物の分岐前に初期のエウカリオットで進化した.
- この発見は,進化の過程でカタヘプシンB酵素が果たす多様な細胞の役割を強調しています.
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