甜高粱蔗糖积累与茎秆中SPS表达的相关性研究

 【目的】以甜高粱为原料生产酒精作为替代能源近年来引起人们的广泛关注，本文试图通过检测蔗糖合成的关键酶-蔗糖磷酸合成酶（SPS）在高粱叶片（源）与茎秆（库）中的表达量，了解高粱体内SPS表达与蔗糖积累的关系，进而探讨蔗糖的代谢机理。【方法】以甜高粱和普通高粱为材料，利用Western blot技术对SPS的蛋白质表达进行检测。【结果】在高粱的生长发育过程中，茎秆中蔗糖含量、叶片和茎秆中SPS蛋白质表达量持续上升，灌浆期达到最高，腊熟期略有下降，它们之间的变化趋势基本一致，甜高粱茎秆蔗糖含量与叶片SPS蛋白质的表达相关系数为0.895，与茎秆SPS蛋白质的表达相关系数为0.781;甜高粱和普通高粱相比，其叶片中SPS表达量差别不明显，而甜高粱茎秆中SPS表达量明显高于普通高粱。【结论】蔗糖为高粱糖分的主要形式，蔗糖积累与叶片和茎秆中SPS的表达相关。在甜高粱中，蔗糖积累主要与茎秆中SPS的表达相关。

Correlation Analysis of Sugar Accumulation and SPS Expression in Sweet Sorghum (Sorghum bicolor L. Moench) Stems

【Objective】Alcohol production by using sweet sorghum (Sorghum bicolor L. Moench) might be an alternative way to provide energy for the world. To better understand the mechanism of sucrose accumulation, the correlation between sucrose content and sucrose phosphate synthetase (SPS) expression was analyzed by monitoring the expression of SPS in leaves (source) and stems (sink). 【Method】 The expression of SPS, the key enzyme of sucrose synthesis in sorghum, was investigated by using Western blot. 【Result】 The results indicated that the sucrose content, the expression of SPS in leaves and stems increased along with the growth of sorghum, reached the highest level at grain filling stage, and decreased at dough stage. The correlation coefficient between sugar content in stems of sweet sorghum and SPS protein expression in leaves was 0.895, and the correlation coefficient was 0.781 as compared with SPS protein expression in stems. In comparison of sweet and normal sorghums, there was no visible difference of SPS expression in leaves, while the SPS expression level in stems of sweet sorghum was much higher than that in normal sorghum. 【Conclusion】Sucrose is the major component of sugar in sorghum, sucrose accumulation was correlated with the expression of SPS in leaves and stems. In sweet sorghum, sucrose accumulation is correlated with the expression of SPS in stems.