NaBC1 is a ubiquitous electrogenic Na+-coupled borate transporter essential for cellular boron homeostasis and cell growth and proliferation
NaBC1 is a ubiquitous electrogenic Na+-coupled borate transporter essential for cellular boron homeostasis and cell growth and proliferation
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DOI：
10.1016/j.molcel.2004.09.030
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发表时间：
2004-11-05
期刊：
影响因子：
16
通讯作者：
Muallem, S
中科院分区：
文献类型：
--
作者：
Park, M;Li, Q;Muallem, S
硼是植物中一种重要的微量营养素，对动物的生长发育可能是必不可少的。虽然硼在植物生命周期中的作用已有很好的文献记载，但对动物细胞中硼的动态平衡和功能知之甚少。NaBc1是AtBor1的哺乳动物同源基因，是一种硼酸转运蛋白。在没有硼酸盐的情况下，NaBc1传导Na+和OH(H+)，而在有硼酸盐存在的情况下，NaBc1作为一个电生的、电压调节的、Na+偶联的B(OH)(4)(-)转运体发挥作用。低浓度时，硼酸盐激活MAPK途径刺激细胞生长和增殖，高浓度时，它具有毒性。相应地，NaBc1的过度表达使硼酸盐的两种作用都左移，而NaBc1的敲除则停止了细胞的生长和增殖。这些发现可能揭示了NaBC1在硼酸动态平衡中以前未被认识到的作用，并为更好地理解动物体内硼酸盐的许多推测的生理作用开辟了道路。
Boron is a vital micronutrient in plants and may be essential for animal growth and development. Whereas the role of boron in the life cycle of plants is well documented, nothing is known about boron homeostasis and function in animal cells. NaBC1, the mammalian homolog of AtBor1, is a borate transporter. In the absence of borate, NaBC1 conducts Na+ and OH(H+), while in the presence of borate, NaBC1 functions as an electrogenic, voltage-regulated, Na+-coupled B(OH)(4)(-) transporter. At low concentrations, borate activated the MAPK pathway to stimulate cell growth and proliferation, and at high concentrations, it was toxic. Accordingly, overexpression of NaBC1 shifted both effects of borate to the left, whereas knockdown of NaBC1 halted cell growth and proliferation. These findings may reveal a previously unrecognized role for NaBC1 in borate homeostasis and open the way to better understanding of the many presumed physiological roles of borate in animals.