一个脏电致Na+/HCO3-共运输体的表达克隆和特征
M F Romero1, M A Hediger, E L Boulpaep
1Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut 06510, USA. mromero@biomed.med.yale.edu
Nature
|May 22, 1997
概括
研究人员发现了一种新型的二碳酸共运输体 (NBC). 这种电源转运器对动物细胞,特别是脏的pH调节至关重要,并且已经成功克隆和表征.
科学领域:
- 生理学 生理学 生理学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 二碳酸盐运输体是动物细胞中细胞内pH的关键调节体.
- 它们对于包括脏在内的各种器官的酸平衡至关重要.
- 对于许多二碳酸盐运输体,特别是与阴离子合的运输体的知识仍然有限.
研究的目的:
- 为了克隆和表征一种新型的离子合二碳酸盐输送器.
- 为了确定电致酸碳酸共运输体 (NBC) 的分子基础.
主要方法:
- 在Xenopus卵细胞中监测细胞内pH值和膜电压.
- 克隆和表达一个候选cDNA编码二碳酸盐输送器的表达.
- 表达蛋白的功能性特征,包括离子依赖性和抑制剂敏感性.
主要成果:
- 成功克隆并对编码1035个氨基酸蛋白的cDNA进行表征.
- 在Xenopus卵细胞中的表达证实了蛋白质是电致的,依赖于 (Na+) 和碳酸 (HCO3-).
- 运输物的活动被DIDS抑制,与二碳酸盐运输相一致.
结论:
- 克隆的cDNA编码了脏电源的二碳酸共运输体 (NBC).
- 这一发现促进了对动物生理学pH调节机制的理解.
- 这项研究为涉及酸稳态的关键转运体提供了分子基础.
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