バクテリアB. hermsiiの抗原多様性は,再編成されたvmp遺伝子の"体"変異によって発生する
1Department of Microbiology, University of Texas Health Science Center, San Antonio 78284-7758.
Cell
|September 9, 1994
まとめ
Borrelia hermsiiは,抗原変異によって免疫反応を回避する. 遺伝子の再編成と突然変異により,多様なVMPタンパク質が作られ,細菌は感染中に生き残ることができます.
科学分野:
- 微生物学 微生物学とは
- 免疫学 免疫学とは
- 遺伝学 遺伝学とは
背景:
- Borrelia hermsiiは,宿主の免疫反応を回避するために,多相抗原的変異を採用しています.
- この変異は,主にプラズミドに存在するVMP (Vira-Mating-Protein) 遺伝子の再配列によって媒介される.
研究 の 目的:
- B. hermsii. の抗原変異を誘発するVMP遺伝子の再編成と変異の正確なメカニズムを解明する.
- VMPの多様性の発生における遺伝子変換の役割を調査する.
主な方法:
- vmp遺伝子のインタープラズミディックおよびイントラプラズミディック再配列の分析.
- 変異を特定するために静止および発現したvmp遺伝子の配列決定.
- vmp偽遺伝子による遺伝子配列の比較分析.
主要な成果:
- 静かなvmp遺伝子の活性化は,イントラプラズミド内欠損を経由するが,インタープラズミド内再結合は行われず,新しい変異の獲得が先行した.
- これらの変異は,再編成された遺伝子の5'端に現れ,元の静音遺伝子には存在しなかった.
- 変異性アレルの有病率は感染中に増加し,配列の差異はvmp偽遺伝子からの遺伝子変換を示唆した.
結論:
- B. hermsiiは,VMPの多様性を生み出すために,遺伝子変換に続く分子内欠損を含むメカニズムを使用しています.
- この戦略は,宿主の免疫環境内で迅速な適応と持続を可能にします.
- 細菌の多様性を生み出すメカニズムは,病原体を排除するための宿主の免疫戦略に並行しています.
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