An improvement of rice chilling tolerance by means of over expression of polyamine biosynthesis genes

通过过量表达多胺生物合成基因提高水稻的耐冷性

基本信息

批准号：
17580010
负责人：
AKIYAMA Takashi
金额：
$ 2.16万
依托单位：
National Agricultural Research Organization
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2007
项目状态：
已结题

项目摘要

Arginine decarboxylase (ADC; EC4.1.1.19) and ornithine decarboxylase (ODC; EC4.1.1.17) play pivotal roles in biosynthesis of putrescine, which is the precursor of the other two higher polyamines, spermidine and spermine. The polyamines have been implicated in many developmental processes and stress responses in higher plants. At the present time, however, only limited information is available for the regulation of polyamine biosynthesis in relation to ADC or ODC gene expression in plants in response to environmental stress. We have cloned ADC and ODC genes from rice, designated here as OsADC1and OsODC1, which encode putative ADC and ODC proteins. Only OsADC1 deduced protein is predicted to have an N-terminal putative signal peptide targeting to chloloroplasts, suggesting that the localization of OsADC1protein may differ from that of OsODC1 protein. Northern-blot analysis revealed that gene expression of OsADC1 was strongly induced by chilling stress, while OsODC1 gene expression increased in response to submergence stress. Interestingly, a concomitant increase in the levels of free putrescine coincided with the increase in levels of OsADC1 and OsODC1mRNA in response to chilling and submergence stress, respectively. To our knowledge, this is the first direct evidence to show that OsADC1 and OsODC1 genes are involved with the increase in putrescine levels that is induced in response to chilling stress and submergence stress in rice seedlings, respectively.

精氨酸脱羧酶（ADC; EC4.1.1.19）和鸟嘌呤脱羧酶（ODC; EC4.1.1.17）在penscine的生物合成中起关键作用，这是其他两个高较高多胺，精子和精子的前体。多胺与较高植物的许多发育过程和压力反应有关。然而，目前，只有有限的信息可用于调节植物中与环境应激的植物中与ADC或ODC基因表达相关的多胺生物合成。我们从大米中克隆了ADC和ODC基因，此处被指定为Osadc1和Osodc1，该基因编码了推定的ADC和ODC蛋白。仅预测OSADC1推导的蛋白质具有N末端推定的信号肽靶向氯托，这表明OSADC1蛋白质的定位可能与OsoDC1蛋白的定位可能不同。北印迹分析表明，osadc1的基因表达是由寒冷应激强烈诱导的，而osodc1基因表达则因淹没应激而增加。有趣的是，自由腐烂的水平伴随着响应于寒冷和浸没压力的osadc1和osodc1mRNA水平的增加。据我们所知，这是第一个直接证据表明，OSADC1和OSODC1基因与腐烂水平的升高有关，这分别响应稻米幼苗的寒冷压力和浸没胁迫而引起。