植物叶片淀粉分解机理研究进展

Advance in the decomposition mechanism of starch in plant leaves

高等植物白天光合作用产物以过渡型淀粉的形式储存于叶片叶绿体,夜晚过渡型淀粉分解为麦芽糖和葡萄糖后转运出叶绿体,用于合成蔗糖、维持叶片呼吸、植物代谢以及生长发育。近年来,通过对拟南芥、水稻、玉米、马铃薯、大豆等植物的研究,发现叶片淀粉分解主要是通过水解和磷酸解两条途径;分解过程受到光照、生物节律和碳源平衡等因素的调控。目前一批重要的植物叶片淀粉分解相关基因已被鉴定出来,随着对这些基因功能研究的不断深入,对植物叶片淀粉分解机理将有更深刻的认识。

Transitory starch, the product of photosynthesis, is usually stored in chloroplasts of leaf of higher plants in daytime, but at night, it would be decomposed into maltose and glucose, then transformed out of chloroplasts for sucrose synthesis, leaf respiration, plant metabolism and growth. Recent studies in Arabidopsis, rice, maize, potato and soybean, etc., suggested that starch decomposition in the leaves had two pathways： hydrolysis pathway and phospholysis pathway, and these two pathways were controlled by light, biological rhythm and carbon balance, etc. At present, a series of related genes of starch decomposition have been identified, with further researches on the function of these genes, people will have more understanding on the decomposition mechanism of starch in plant leaves.