组织因子通路抑制剂-α在细胞表面结合中的Kunitz-3域的作用
1Division of Hematology, Washington University School of Medicine, St Louis, Mo, USA.
Circulation
|November 24, 2004
概括
组织因子通路抑制剂-α (TFPI-α) 的Kunitz-3域和C端区域对于其细胞表面定位至关重要. 在Kunitz-3中的P1残留物 (R199) 对于这种TFPI-alpha结合至关重要.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 组织因子通路抑制剂-α (TFPI-α) 通过三个Kunitz域调节凝血.
- 昆茨-1 抑制了 VIIa 因素,昆茨-2 抑制了 Xa 因素.
- 在此之前,TFPI-alpha的Kunitz-3域的功能是未知的.
研究的目的:
- 阐明TFPI-alpha的Kunitz-3域和C端在细胞表面结合中的作用.
- 在Kunitz-3中识别特定的残留物,对TFPI-alpha定位至关重要.
主要方法:
- 设计的截断和突变的TFPI-alpha变体 (例如,TFPI-alpha (desK3),TFPI-alpha (R199L)).
- 在小鼠乳腺 (C127) 和内皮 (b-end3) 细胞系中表达的变异.
- 使用流式细胞计量和分析的TFPI-alpha淘汰细胞量化细胞表面结合.
主要成果:
- 缺乏Kunitz-3或C终端域的TFPI-alpha变体显示细胞结合显著减少或不存在.
- 昆茨-3 P1残留物 (R199L) 的突变也影响了TFPI-α结合.
- Knockdown 的内源性TFPI-alpha证实了这些域对于细胞表面定位的必要性.
结论:
- 昆尼茨-3域和C端区域对于TFPI-alpha的最佳细胞表面结合至关重要.
- 在Kunitz-3域内的P1残留物 (R199) 对此定位至关重要.
- 库尼茨-3域在TFPI-alpha.的细胞表面定位中起着关键作用.
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