Jiangsu Key Laboratory of Crop Genetics and Physiology/Key Laboratory of Plant Functional Genomics of the Ministry of Education, College of Agriculture, Yangzhou University, Yangzhou 225009, China; Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding / Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China.
Jiangsu Key Laboratory of Crop Genetics and Physiology/Key Laboratory of Plant Functional Genomics of the Ministry of Education, College of Agriculture, Yangzhou University, Yangzhou 225009, China.
Food Chem. 2019 Dec 15;301:125258. doi: 10.1016/j.foodchem.2019.125258. Epub 2019 Jul 25.
Starch is the abundant component in rice endosperm, and its microstructure determines the quality and functional properties of rice grain. It is well known that the starch fine structure is markedly influenced by high temperature during grain filling. However, it is poorly understood on the competition among starch synthesis related enzymes as well as the interaction between amylose and amylopectin biosynthesis under increased growing temperature. In this study, the non-waxy and waxy rice were planted under normal and high temperatures. Parameterizing analysis of the starch microstructure using mathematical models proved that amylose synthesis competed with the elongation of long amylopectin chains (DP＞60); Short chains of amylopectin can be used as the substrate for elongation of longer amylopectin chains; High temperature eliminated the consistency and regularity of the synthesis of amylose and amylopectin. In addition, enzyme assay proved the validity of fitting results from mathematical modeling analysis of starch.
淀粉是稻米胚乳中的丰富成分，其微观结构决定了稻米的品质和功能特性。众所周知，在灌浆期间高温会显著影响淀粉的精细结构。然而，对于在较高生长温度下淀粉合成相关酶之间的竞争以及直链淀粉和支链淀粉生物合成之间的相互作用，人们的了解甚少。在这项研究中，糯稻和非糯稻在正常温度和高温下种植。使用数学模型对淀粉微观结构进行参数分析证明，直链淀粉的合成与长支链淀粉链（DP＞60）的伸长竞争；支链淀粉的短链可以作为伸长更长支链淀粉链的底物；高温消除了直链淀粉和支链淀粉合成的一致性和规律性。此外，酶测定证明了数学建模分析淀粉拟合结果的有效性。
