Expression patterns of the rice class I metallothionein gene family in response to lead stress in rice seedlings and functional complementation of its members in lead-sensitive yeast cells  

作　　者：XU YuFeng ZHOU GongKe ZHOU Lu LI YiQin LIU JinYuan 

机构地区：[1]Laboratory of Molecular Biology and Protein Science Key Laboratory of the Ministry of Education, Department of Biological Sciencesand Biotechnology, Tsinghua University, Beijing 100084, China

出　　处：《Chinese Science Bulletin》2007年第16期2203-2209,共7页

基　　金：Supported by the State Key Basic Research and Development Plan of China (Grant No. 2006CB101706);the National Natural Science Foundation of China (Grant Nos. 30270753 & 30370804)

摘　　要：Metallothioneins (MTs) are a group of low molecular mass and cysteine-rich proteins that can chelate heavy-metal ions. In this paper,Northern blot analysis was used to investigate the influence of lead stress on the expression patterns of 10 rice class I MT genes (OsMT-Is) in rice seedlings. With the ex-ception of OsMT-I-3b,the data demonstrate dynamic changes of 9 OsMT-I transcripts in response to Pb2+ treatment in rice seedling roots. Of these genes,transcription of OsMT-I-1a,OsMT-I-1b,OsMT-I-2c,OsMT-I-4a,OsMT-I-4b and OsMT-I-4c increased significantly,while transcription of OsMT-I-2a and OsMT-I-3a increased marginally. In contrast,the expression of OsMT-I-2b was inhibited. Pb2+ induced the expression of 6 OsMT-I genes in seedling shoots,but had no obvious effects on the expression of OsMT-I-1a,OsMT-I-1b,OsMT-I-4a and OsMT-I-4b. All the 10 OsMT-Is had enhanced lead tolerance when heterologously expressed in lead-sensitive yeast mutant cells. These results provide an expression profile of the rice MT gene family in response to Pb2+ stress in rice seedlings and demonstrate in-creased lead tolerance in sensitive yeast mutant cells expressing OsMT-Is. This study lays a foundation for further analysis of the role of the rice MT gene family in respond to Pb2+ stress.Metallothioneins （MTs） are a group of low molecular mass and cysteine-rich proteins that can chelate heavy-metal ions. In this paper, Northern blot analysis was used to investigate the influence of lead stress on the expression patterns of 10 rice class I MT genes （OsMT-Is） in rice seedlings. With the exception of OsMT-I-3b, the data demonstrate dynamic changes of 90sMT-1 transcripts in response to Pb^2＋ treatment in rice seedling roots. Of these genes, transcription of OsMT-l-1a, OsMT-l-1b, OsMT-l-2c, OsMT-l-4a, OsMT-l-4b and OsMT-l-4c increased significantly, while transcription of OsMT-l-2a and OsMT-l-3a increased marginally. In contrast, the expression of OsMT-l-2b was inhibited. Pb^2＋ induced the expression of 60sMT-I genes in seedling shoots, but had no obvious effects on the expression of OsMT-l-1a, OsMT-l-1b, OsMT-l-4a and OsMT-l-4b. All the 10 OsMT-ls had enhanced lead tolerance when heterologously expressed in lead-sensitive yeast mutant cells. These results provide an expression profile of the rice MT gene family in response to Pb^2＋ stress in rice seedlings and demonstrate increased lead tolerance in sensitive yeast mutant cells expressing OsMT-ls. This study lays a foundation for further analysis of the role of the rice MT gene family in respond to Pb^2＋ stress.

关 键 词：水稻 金属硫蛋白 基因表达 铅 酵母细胞 

分 类 号：S511[农业科学—作物学]