过表达抗miR98的OsmCSD2基因提高水稻的重金属抗性

CSD（Cu／Zn superoxide dismutases）基因在拟南芥中参与多种胁迫应答，而miR398是CSD基因响应胁迫的原因。此处，我们成功克隆出了水稻的OsCSD2基因，并根据密码子的兼并性，突变了miR398作用的位点，但不改变其氨基酸序列，得到新的抗miR398的OsmCSD2，构建过表达载体并转入水稻中。对阳性转基因株系的分子鉴定表明，过表达植株的OsmCSD2基因获得了高表达。在重金属铜胁迫下，转基因株系表现出良好的抗逆性，H2O2含量显著低于野生型。

Over-Expression of miR398-Resistant Version of OsCSD2 Gene in Rice Enhance Tolerance to Heavy Metal Stress

CSD （Cu/Zn superoxide dismutases） genes in Arabidopsis involve in multiple stress responses, and miR398 is the cause of CSD gene response to stress. Here, we have successfully cloned OsCSD2 gene, and mutated the sequence of sites targeted by miR398 according to the degeneracy of codons, but didn＇t change the amino acid sequence in OsCSD2. Thus, we got new anti-miR398-version of CSD2 （named as OsmCSD2）, built an expression vector and transferred to the rice. Positive molecular identification of transgenic plants showed that over-expression of plant obtained a high expression of OsmCSD2 gene. Under the Cu stress, transgenic plants showed good resistance, and H2O2 content was significantly lower than that of wild type.