Beltran Jean L, Bain Richara K, Stiefel Marie J, McDonnell Alexis S, Carr Natalie N, Thurtle-Schmidt Bryan H
Department of Biology, Davidson College, Davidson, NC 28035, USA.
MicroPubl Biol. 2022 Jul 20;2022. doi: 10.17912/micropub.biology.000605. eCollection 2022.
Borate is an essential micronutrient in plants regulated by borate transporters, which also protect both yeast and plants from toxically high levels of borate and share homology with the human SLC4 transporters. SLC4A11 is linked to congenital hereditary endothelial dystrophy and was initially reported to transport borate before subsequent studies rebutted this conclusion. To better understand the transport activities of purported borate transporters, we tested the ability of and eleven borate transporters from and to complement a deletion in . We show that , , , , and can each complement , while the rest of the transporters tested do not rescue growth. Additionally, quantification of intracellular borate content demonstrates that SLC4A11 does not export borate in yeast, supporting studies that its transported substrate is not borate.
硼酸盐是植物中的一种必需微量营养素,受硼酸盐转运蛋白调控,这些转运蛋白还能保护酵母和植物免受高毒性硼酸盐水平的影响,并且与人类SLC4转运蛋白具有同源性。SLC4A11与先天性遗传性内皮营养不良有关,最初有报道称其能转运硼酸盐,但后续研究反驳了这一结论。为了更好地了解所谓硼酸盐转运蛋白的转运活性,我们测试了来自拟南芥和水稻的11种硼酸盐转运蛋白补充酿酒酵母中硼酸盐转运蛋白缺失的能力。我们发现,AtBOR1、AtBOR2、AtBOR4、AtBOR5和OsBOR1各自都能补充硼酸盐转运蛋白缺失,而其余测试的转运蛋白则不能挽救生长。此外,细胞内硼酸盐含量的定量分析表明,SLC4A11在酵母中不输出硼酸盐,这支持了其转运底物不是硼酸盐的研究。