Isolation of Three Metallothionein Genes and Their Roles in Mediating Cadmium Resistance

• 全文链接

分离油菜体内镉（Cd）积累和耐受的基因，揭示其功能机制

关键词：

来源：

Agronomy

全文链接：

//agri.nais.net.cn/topic/downloadFile/87ffebd0-d401-4677-980d-a98e743c0b13

来源地址：

https://www.mdpi.com/2073-4395/12/12/2971

资源所属：

蔬菜育种专题

类型：

学术文献

语种：

英语

原文发布日期：

2022-11-26

摘要：

Isolating the genes responsible for cadmium (Cd) accumulation and tolerance in oilseed rape and uncovering their functional mechanism is of great significance for guiding genetic improve-ment to cope with heavy metal pollution. In this study, we screened the cDNA library of Brassica napus cv. Westar using a yeast genetic complementation system and isolated BnMT2-22a, BnMT2-22b and BnMT3b, which can mediate Cd tolerance in yeast. They all have two cysteine-rich domains in their sequence. Ectopic expression of these MTs demonstrated that all of them enhanced Cd and Cu tolerance in yeast, but had no effect on Mn and Zn tolerance. The fusion of the red fluorescent protein mRFP did not affect their function in mediating Cd tolerance, and using these functional fusion proteins we observed that they were all localized in cytosol. Meanwhile, their expression in yeast did not affect the accumulation of Cd in the yeast transformants. Gene expression analyses found that BnMT2-22a, BnMT2-22b and BnMT3b were all induced by Cd in roots, and BnMT3b was also significantly induced in shoots. These results indicate that the genes BnMT2-22a, BnMT2-22b and BnMT3b isolated with cDNA library screening can mediate Cd tolerance, and they may detoxify Cd via cytosolic chelation.