Institute of Genetic Resources, Faculty of Agriculture, Kyushu University , Fukuoka 812-8581 , Japan ; Plant Resources Center, Vietnamese Academy of Agricultural Science , Ankhanh, Hoaiduc, Hanoi , Vietnam.
Institute of Genetic Resources, Faculty of Agriculture, Kyushu University , Fukuoka 812-8581 , Japan.
Breed Sci. 2014 Jun;64(2):142-8. doi: 10.1270/jsbbs.64.142. Epub 2014 Jun 1.
Amylose content is one of the most important factors influencing the physical and chemical properties of starch in rice. Analysis of 352 Vietnamese rice cultivars revealed a wide range of variation in apparent amylose content and the expression level of granule-bound starch synthase. On the basis of single-nucleotide polymorphisms (SNP) at the splicing donor site of the first intron and in the coding region of the granule-bound starch synthase I gene, Waxy gene, alleles can be classified into seven groups that reflect differences in apparent amylose content. The very low and low apparent amylose content levels were tightly associated with a G to T in the first intron whereas intermediate and high amylose was associated with a T genotype at SNP in exon 10. The correlation between the combination of T genotype at SNP in the first intron, C in exon 6, or C in exon 10 was predominant among low amylose rice varieties. Our analysis confirmed the existence of Wx (op) allele in Vietnamese rice germplasm. The results of this study suggest that the low amylose properties of Vietnamese local rice germplasm are attributable to spontaneous mutations at exons, and not at the splicing donor site.
直链淀粉含量是影响稻米淀粉理化特性的最重要因素之一。对 352 份越南稻种的分析表明，直链淀粉含量和颗粒结合型淀粉合成酶的表达水平存在广泛的差异。基于第一个内含子剪接供体位点和颗粒结合型淀粉合成酶 I 基因编码区的单核苷酸多态性（SNP），蜡质基因等位基因可分为 7 组，反映了直链淀粉含量的差异。非常低和低直链淀粉含量水平与第一个内含子中的 G 到 T 紧密相关，而中间和高直链淀粉与 SNP 在第 10 外显子中的 T 基因型相关。在低直链淀粉水稻品种中，第一个内含子 SNP 的 T 基因型、第 6 外显子的 C 或第 10 外显子的 C 组合之间的相关性占主导地位。本研究证实了越南稻种种质中存在 Wx(op)等位基因。研究结果表明，越南地方稻种种质的低直链淀粉特性归因于外显子的自发突变，而不是剪接供体位点。
