甘薯贮藏根淀粉代谢相关基因表达分析

Expression of Starch Metabolism Related Genes in Storage Roots of Sweet Potato

甘薯淀粉含量高,是一种重要的粮食作物和工业原料。然而,甘薯贮藏根发育过程中淀粉代谢途径相关基因昼夜周期变化规律尚不完全清楚。为探讨甘薯贮藏根发育过程中淀粉代谢相关基因昼夜周期变化规律,本研究以4个不同淀粉含量的甘薯品种为试验材料,采用qRT-PCR法对淀粉代谢相关基因全天的表达模式进行分析。结果表明:IbAGPa、IbSS、IbGBSSⅠ、IbSBEⅠ、IbSBEⅡ、Ibα-amylase基因的表达均呈现先升高后降低的趋势。淀粉合成相关基因(IbAGPa、IbSS、IbGBSSⅠ、IbSBEⅠ、IbSBEⅡ)的表达高峰出现在12时到15时,淀粉降解相关基因(Ibα-amylase)的表达高峰出现在15时之后。在不同淀粉含量的甘薯品种中,淀粉代谢相关基因的表达在整个昼夜周期内都发生周期性的变化,且表达趋势相似。本研究进一步丰富了我们对甘薯贮藏根淀粉代谢调控机制的认识。

Sweet potato is an important food crop and industrial raw material because of its high starch content.In order to explore the diurnal cycle of genes related to starch metabolism pathway in the development of storage roots of sweet potato,four cultivars with different starch content were selected as experimental materials.The expression patterns of starch metabolism related genes were analyzed by qRT-PCR.The results showed that genes of IbAGPa,IbSS,IbGBSSⅠ,IbSBEⅠ,IbSBEⅢand Ibα-amylase had an increased expression followed by a decreasing trend.The expression peak of the genes related to starch synthesis(IbAGPa,IbSS,IbGBSSⅠ,IbSBEⅠand IbSBEⅡ)appeared at 12 noon to 3 pm,and the expression peak of the starch degradation-related gene(Ibα-amylase)appeared after 3 pm.The results showed that the expression of starch metabolism related genes changed periodically throughout the diurnal cycle and that of the expression was similar in sweet potato cultivars with different starch contents.This study further enriched our understanding of the regulation mechanism of starch metabolism in the storage roots of sweet potato.