颗粒结合型淀粉合成酶研究进展

本文综述了小麦胚乳中合成直链淀粉的关键酶——颗粒结合型淀粉合成酶(GBSS)的研究进展，展望了GBSS的研究前景。小麦中的GBSS基因在种子中特异表达；控制3个Waxy，位点的基因Wx—A1、Wx—B1和Wx—D1，分别位于7AS、4AL和7DS上；六倍体小麦和二倍体小麦中3个GBSS的DNA序列从起始密码子到终止密码子，Wx—A1为2781bp，Wx-B1为2794bp，Wx—D1为2862bp。基因的完全编码区含有11个外显子和10个内含子，在核苷酸序列上三个糯基因彼此之间有惊人的同源性；研究表明，直链淀粉含量和淀粉糊化特性受Wx—B1的影响最大，其次是Wx-D1缺失蛋白，Wx-A1缺失蛋白的影响最小。GBSS的鉴定技术包括I2—KI染色、电泳和分子标记技术鉴定。

Progress in Research of Granule-Bound Starch Synthase

The progress in research granule-bound starch synthase (GBSS) which was responsible for amylose synthesis in cereal endosperm, was reviewed in the paper. The expression of GBSS was specific in seed. The genie loci containing the genes encoding wheat GBSS were found on chromosomes 7AS, 4AL and 7DS respectively. The lengths of the three genes were 2 781 bp, 2 794 bp and 2 862 bp, respectively. The entire coding region consisted of 11 extrons and 10 introns. There were significant homology among the three genes. The effects of Wx-A1, Wx -B1 and Wx-D1 on amylose content and starch pasting properties in common wheat were Wx-B1