Heterologous expression of Pteris vittata arsenite antiporter PvACR3;1 reduces arsenic accumulation in plant shoots
writer：Yanshan Chen, Chenyu Hua, Meng-Ru Jia, Jingwei Fu, Xue Liu, Yong-He Han, Yungen Liu, Bala Rathinasab
keywords：无
source：期刊
specific source：Environmental Science & Technology
Issue time：2017年
Arsenic (As) is a toxic carcinogen so it is crucial to decrease As accumulation in crops to reduce its risk to human health. Arsenite (AsIII) antiporter ACR3 is critical for As metabolism in organisms, but it is lost in flowering plants. Here, a novel ACR3 from As-hyperaccumulator Pteris vittata, PvACR3;1, was cloned and expressed in Saccharomyces cerevisiae (yeast), Arabidopsis thaliana (model plant) and Nicotiana tabacum (tobacco). Yeast experiments showed that PvACR3;1 functioned as AsIII-antiporter to mediate AsIII efflux to external medium. At 5 μM AsIII, PvACR3;1 transgenic Arabidopsis accumulated 14?29% higher As in the roots, but 55?61% lower As in the shoots compared to WT control, showing lower As translocation. Besides, transgenic tobacco under 5 μM AsIII or AsV also showed similar results, indicating that expressing PvACR3;1 increased As retention in plant roots. Moreover, observation of PvACR3;1?green fluorescent protein fusions in transgenic Arabidopsis showed that PvACR3;1 localized to the vacuolar membrane, indicating PvACR3 mediated AsIII sequestration into vacuoles, consistent with increased root As. Soil experiments showed ~22% lower As in the shoots of transgenic tobacco than control. Thus, our study provides a potential strategy to limit As accumulation in plant shoots, representing the first report to decrease As translocation by sequestrating AsIII into vacuoles and shedding lights on engineering low-As crops for food safety.