Functional analysis of spermidine for conferring abiotic stress tolerance

与野生型（WT）相比，盐或镉胁迫下，转基因欧洲梨株系与减少亚精胺（spd）合酶（SPDS）的表达表现出严重的影响表型。然而，抑制表型大大减轻应用Spd。Spd对WT的施用可以赋予胁迫耐受性，而SPDS抑制剂对SPDS过表达的梨的施用显示胁迫耐受性降低。我们还通过影响抗氧化系统，证明了Spd在植物抗逆性中的重要性。利用差异显示技术和cDNA微阵列技术，成功分离到了SPDS过表达株和野生型中表达量差异显著的几个基因，包括Bispherin和过氧化物酶。

Transgenic European pear lines with reduced spermidine(spd) synthase(SPDS) expression showed severe effect on phenotypes compared with the wild-type(WT) under salt or cadmium stress. However, repressed phenotype was much alleviated by application of Spd. Application of Spd to WT can confer stress tolerance, while application of SPDS inhibitor to SPDS-overexpressing pear showed reduction of stress tolerance. We also showed the evidence for the importance of Spd in stress tolerance by influencing antioxidant system. Moreover, several genes including dehydrin and peroxidase whose expression levels were significantly different in SPDS-overexpressing line and WT, were successfully isolated by differential display and cDNA microarray.