Department of Biological Science and Technology, Tokyo University of Science, Katsushika, Tokyo, Japan.
Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, Abiko, Chiba, Japan.
Biosci Biotechnol Biochem. 2022 Oct 20;86(11):1599-1604. doi: 10.1093/bbb/zbac152.
Cesium (Cs) in the environment is primarily absorbed by a potassium (K) transporter. OsHAK5 is a KT/HAK/KUP family K-transporter showing a high affinity for K. We created cultured rice cells whose OsHAK5 was knocked down by RNAi (named KD). In the medium containing 1.0 m m and less K, the growth of KD was significantly suppressed, suggesting that OsHAK5 greatly contributed to K absorption under limited K conditions. Although Cs suppressed the growth of KD and WT, stronger inhibition was observed on KD. Both KD and WT accumulated similar amounts of Cs when they were cultured in a medium containing Cs, whereas lower amounts of K were detected in KD. These results suggest that OsHAK5 was less involved in the absorption of Cs, although it was essential to K absorption under limited K conditions. In contrast, this means that another transporter may contribute to cesium uptake in rice.
环境中的铯（Cs）主要通过一种钾（K）转运体吸收。OsHAK5 是一种 KT/HAK/KUP 家族的 K 转运体，对 K 具有高亲和力。我们创建了通过 RNAi 敲低 OsHAK5 的培养水稻细胞（命名为 KD）。在含有 1.0 m m 及更低浓度 K 的培养基中，KD 的生长受到显著抑制，这表明 OsHAK5 在低钾条件下对 K 吸收有很大贡献。尽管 Cs 抑制了 KD 和 WT 的生长，但对 KD 的抑制作用更强。当它们在含有 Cs 的培养基中培养时，KD 和 WT 积累的 Cs 量相似，而在 KD 中检测到的 K 量较低。这些结果表明，尽管 OsHAK5 在低钾条件下对 K 吸收至关重要，但它对 Cs 的吸收参与较少。相反，这意味着另一种转运体可能有助于水稻对铯的吸收。
