木薯己糖激酶MeHXK4的功能鉴定

Functional Complementation of Cassava Hexokinase MeHXK4 in Yeast

己糖激酶可催化葡萄糖和果糖磷酸化生成磷酸己糖,在植物的碳水化合物代谢及糖信号转导中具有重要的作用。前期我们已克隆获得木薯己糖激酶基因Me HXK4,根据生物信息学分析其编码的蛋白可能不具有催化活性。本研究主要利用己糖激酶酵母突变菌株YSH7.4-3C进行酵母功能互补实验,鉴定Me HXK4是否具有催化己糖磷酸化的功能。结果发现,转了p DR195-Me HXK4的YSH7.4-3C酵母可以在以葡萄糖或果糖为唯一碳源的培养基中生长,表明Me HXK4能催化己糖磷酸化为酵母的生长提供碳水化合物和能量。本研究结果为进一步研究Me HXK4的生理功能提供依据。

Hexokinase catalyzes the phosphorylation of glucose and fructose generated hexose monophosphate,plays an important role in carbohydrate metabolism and sugar signal transduction in plants. We have cloned and obtained the cassava hexokinase gene MeHXK4, which may not be catalytically active according to bioinformatics analysis. In this study, we used the yeast mutant strain YSH7.4-3 C to perform yeast functional complementation experiment to determine whether MeHXK4 had the function of catalyzing the phosphorylation of hexose. It was found that YSH7.4-3 C yeast with pDR195-MeHXK4 could be grown in medium with glucose or fructose as the sole carbon source, indicating that MeHXK4 could catalyze the phosphorylation of hexose to provide carbohydrate and energy for yeast growth. The results of this study laid the foundation for the further study of the physiological function of MeHXK4.