红细胞Glut1触发了哺乳动物不能合成维生素C的脱酸的吸收
Amélie Montel-Hagen1, Sandrina Kinet, Nicolas Manel
1Institut de Génétique Moléculaire de Montpellier, CNRS, Université Montpellier I and II, Montpellier, France.
Cell
|March 25, 2008
概括
在发育过程中,人类红血细胞通过Glut1运输维生素C前体 (DHA),而不是葡萄糖. 这弥补了无法合成维生素C的不足,涉及胃蛋白调节.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生物化学
- 人体生理学 人体生理学
背景情况:
- 人体红细胞表现出最高的葡萄糖输送物Glut1水平.
- 在红细胞发育 (红细胞形成) 过程中Glut1的作用和调节尚不清楚.
研究的目的:
- 调查Glut1功能和调节在人体红色素形成过程中.
- 确定红细胞发育过程中营养物质运输改变背后的机制.
主要方法:
- 在红细胞生成过程中分析Glut1转录水平和葡萄糖/DHA运输.
- 识别参与红细胞运输的调节蛋白.
主要成果:
- 尽管Glut1转录增加,但在红色素形成过程中葡萄糖运输减少.
- L-脱酸 (DHA) 运输显著增强,由胃素调节.
- 红细胞Glut1和DHA吸收是人类和缺乏维生素C合成的哺乳动物的特征.
结论:
- 红细胞Glut1和胃的联合表达是维生素C合成缺乏症的补偿机制.
- 这突显了人类红细胞在营养物质运输方面的独特适应性.
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