胚の血管発達における組織因子の役割
P Carmeliet1, N Mackman, L Moons
1Center for Transgene Technology and Gene Therapy, Flanders Interuniversity Institute for Biotechnology, Leuven, Belgium.
Nature
|September 5, 1996
まとめ
組織因子遺伝子 (TF) の非活性化により,マウスの血液循環が異常になり,胚が死亡しました. これは,組織因子が適切な血管の発達と機能に不可欠であることを示唆しています.
科学分野:
- 発達生物学 発達生物学について
- 血液学 ヘマトロジ
- 分子生物学は分子生物学である.
背景:
- 組織因子 (TF) は血液の凝固を誘発し,血栓症,炎症,癌に関与しています.
- TFはサイトカイン受容体超家族の一員で,因子VII/VIIaの受容体および共因子として作用する.
- 凝固を超えて,TFは細胞内信号伝達,転移,血管新生,胚形成に影響を与える.
研究 の 目的:
- 胚の発達と血管形成における組織因子の役割を調査する.
- 組織因子遺伝子不活性化が胚の早期血管化に及ぼす影響を決定する.
主な方法:
- マウスにおける組織因子 (TF) の遺伝子不活性化.
- 8.5. 胚の日までの胚の発達と血管形態の分析
- TF-null胚のビテリン系血管における滑らかな筋肉のアクチン発現の評価.
主要な成果:
- TF遺伝子の無活性化により,胚の8.5.5日を過ぎた胚の循環に異常な黄色の袋が生じました.
- TF-null胚は衰弱と死亡を示し,重大な発達障害を示した.
- TF-nullマウスのビテリン系血管には,滑らかな筋肉のアルファ-アクチン発現するメゼンキマ細胞が不足していた.
結論:
- 組織因子は,胚の血管発達において重要な役割を果たします.
- TFの欠如は,メゼンキマ細胞の募集に影響を与えることによって,血管壁の組織を混乱させます.
- TFは,胚形成初期に循環器の完全性を維持するために不可欠です.
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