Isolation and characterization of three metallothionein genes in sweetpotato
Heavy metal pollutions of water and soil are serious environment problems. It causes direct health hazards to human beings and affects the crop productivity in heavy metal contaminated soils. Phy-toremediation which uses plants for removal of contaminants is getting highlighted because it is a cost effective and environmentally friendly technology. To overcome heavy metal stress,plants produce metal chelating proteins such as metallothioneins (MTs) and phytochelatins. MTs are low molecular weight, cysteine-rich,metal binding proteins and widely distributed in living organisms. To remediate the heavy metals in contaminated areas,we have cloned three MT genes from the leaves of sweetpotato Ipomoea batatas (L.) Lam. . According to their cysteine residue alignment,three MT genes were classified into type1 ,type2,and type3 MT gene,respectively. IbMT1 gene was the most abundantly transcribed in the plants. It was predominantly expressed in the leaves,roots and callus. lbMT2 transcript was detected only in the stem and IbMT3 was specifically expressed in the stems and leaves. Expression profiles of lbMT1 gene under various exogenous factors were investigated in cultured cells of sweetpotato. lbMT1 gene expression was strongly induced by Fe and Mn and moderately induced by Cu. Significant increase in the transcript level of lbMT1 was also found in response to ABA,methyl jasmonate and ethephon. Abiotic stresses such as NaCl and cold treatments also up-regulated IbMT1 expression. These results imply that IbMTs would be applicable to the development of plants with enhanced tolerance to environmental stresses as well as heavy metal stresses.
sweetpotato metallothionein ROS heavy metal phytoremediation
AHN Young Ock KIM Sun Ha LEE Haeng-Soon KWAK Sang-Soo
Environmental Biotechnology Research Center,Korea Research Institute of Bioscience and Biotechnology (KRIBB),Daejeon 305-806,Korea
国际会议
徐州
英文
97-105
2010-11-27（万方平台首次上网日期，不代表论文的发表时间）