文献类型：期刊文献

英文题名：Sulfur nutrition stimulates lead accumulation and alleviates its toxicity in Populus deltoides

作者：Ma, Chaofeng[1,2] Chen, Yinghao[2] Ding, Shen[2] Li, Ziliang[2] Shi, Wen-Guang[1] Zhang, Yi[2] Luo, Zhi-Bin[1]

第一作者：Ma, Chaofeng

通信作者：Luo, ZB[1]

机构：[1]Chinese Acad Forestry, Res Inst Forestry, State Key Lab Tree Genet & Breeding, Beijing 100091, Peoples R China;[2]Northwest A&F Univ, Coll Forestry, Yangling 712100, Shaanxi, Peoples R China

年份：2018

卷号：38

期号：11

起止页码：1724-1741

外文期刊名：TREE PHYSIOLOGY

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000452458300010)】；

基金：This study was jointly supported by the Special Fund on Essential Research for National Non-profit Institutions to the Chinese Academy of Forestry (Grant no. CAFYBB2018ZY001-2) and the National Natural Science Foundation of China (Grant nos. 31470618 and 31670609).

语种：英文

外文关键词：glutathione; lead; phytochelatin; phytoremediation; poplar; sulfate transporter; sulfur

摘要：Sulfur (S) can modulate plant responses to toxic heavy metals, but the underlying physiological and transcriptional regulation mechanisms remain largely unknown. To investigate the effects of S supply on lead (Pb)-induced toxicity in poplars, Populus deltoides monilifera (Aiton) Eckenw. saplings were exposed to 0 or 50 mu M Pb together with one of the three S concentrations (0 (low S), 100 (moderate S) or 1500 (high S) mu M Na2SO4). Populus deltoides roots absorbed Pb and it was partially translocated to the aerial organs, thereby decreasing the CO2 assimilation rate and leaf growth. Lead accumulation in poplars caused the overproduction of O-2(-) and H2O2 to induce higher levels of total thiols (T-SH) and glutathione (GSH). Lead uptake by the roots and its accumulation in the aerial organs were repressed by low S application, but stimulated by high S supply. Lead-induced O-2(-) and H2O2 production were exacerbated by S limitation, but alleviated by high S supply. Moreover, the concentrations of S-containing antioxidants including T-SH and GSH were reduced in S-deficient poplars, but increased in high S-treated plants, which corresponded well to the changes in the activities of enzymes involved in S assimilation and GSH biosynthesis. The transcript levels of both genes encoding sulfate transporters, i.e., SULTR1.1 and SULTR2.2, were elevated by low S application or high S supply in the roots, and the transcriptional upregulation of both genes was more pronounced under Pb exposure. Furthermore, the mRNA levels of several genes involved in S assimilation and the biosynthesis of GSH and phytochelatins, i. e., ATPS1, ATPS3, GSHS1, GSHS2 and PCS1, were upregulated in poplar roots with high S supply, particularly under Pb exposure. These results indicate that a high S supply can stimulate Pb accumulation and reduce its toxicity in poplars by improving S assimilation and stimulating the biosynthesis of S-containing compounds including T-SH and GSH.