Overexpression of OsLCT2, a Low-Affinity Cation Transporter Gene, Reduces Cadmium Accumulation in Shoots and Grains of Rice.
Overexpression of OsLCT2, a Low-Affinity Cation Transporter Gene, Reduces Cadmium Accumulation in Shoots and Grains of Rice.
复制标题
OsLCT2（一种低亲和力阳离子转运蛋白基因）的过度表达可减少水稻芽和籽粒中镉的积累。
DOI：
10.1186/s12284-021-00530-8
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发表时间：
2021-10-24
期刊：
影响因子：
--
通讯作者：
Zhao B
中科院分区：
文献类型：
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作者：
Tang L;Dong J;Tan L;Ji Z;Li Y;Sun Y;Chen C;Lv Q;Mao B;Hu Y;Zhao B
镉（Cd）污染大米是影响食品安全的严重问题。了解水稻籽粒中Cd积累的分子调控机制对于降低籽粒中Cd浓度至关重要。我们在水稻中鉴定了一个低亲和力阳离子转运蛋白家族成员OsLCT 2。它是一种膜蛋白。OsLCT 2在根的伸长区和成熟区的所有组织中均有表达，在靠近木质部的中柱细胞和周鞘细胞中表达最强。在Cd污染的水稻土中，过量表达OsLCT 2的水稻植株显著降低了稻草和籽粒中Cd的含量。水培试验表明，过量表达该基因降低了Cd从根向地上部的转运速率，降低了木质部汁液和地上部中Cd的含量。此外，它的过表达增加了根中的锌浓度，通过上调OsZIP 9的表达，一个负责锌吸收的基因。过量表达OsLCT 2基因可通过限制Cd进入木质部的量和限制Cd从根向地上部的转运来降低水稻地上部和籽粒中Cd的积累。因此，OsLCT 2基因是一个很有希望的基因资源，可以通过基因工程的方法降低水稻籽粒中Cd的积累。在线版本包含补充材料，可通过10.1186/s12284-021-00530-8获取。
Cadmium (Cd)-contaminated rice is a serious issue affecting food safety. Understanding the molecular regulatory mechanisms of Cd accumulation in rice grains is crucial to minimizing Cd concentrations in grains. We identified a member of the low-affinity cation transporter family, OsLCT2 in rice. It was a membrane protein. OsLCT2 was expressed in all tissues of the elongation and maturation zones in roots, with the strongest expression in pericycle and stele cells adjacent to the xylem. When grown in Cd-contaminated paddy soils, rice plants overexpressing OsLCT2 significantly reduced Cd concentrations in the straw and grains. Hydroponic experiment demonstrated its overexpression decreased the rate of Cd translocation from roots to shoots, and reduced Cd concentrations in xylem sap and in shoots of rice. Moreover, its overexpression increased Zn concentrations in roots by up-regulating the expression of OsZIP9, a gene responsible for Zn uptake. Overexpression of OsLCT2 reduces Cd accumulation in rice shoots and grains by limiting the amounts of Cd loaded into the xylem and restricting Cd translocation from roots to shoots of rice. Thus, OsLCT2 is a promising genetic resource to be engineered to reduce Cd accumulation in rice grains. The online version contains supplementary material available at 10.1186/s12284-021-00530-8.