Detection of allelic variation at the Wx locus with single-segment substitution lines in rice (Oryza sativa L.)
Detection of allelic variation at the Wx locus with single-segment substitution lines in rice (Oryza sativa L.)
复制标题
用单片段替换系检测水稻 (Oryza sativa L.) 中 Wx 基因座的等位基因变异
DOI：
10.1007/s11032-011-9647-x
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发表时间：
2012-06-01
影响因子：
3.1
通讯作者：
Zhang, Guiquan
中科院分区：
文献类型：
--
作者：
Teng, Bin;Zeng, Ruizhen;Zhang, Guiquan
稻米直链淀粉表观含量（AAC）是稻米食味和蒸煮品质的重要决定因素，其主要由编码颗粒结合淀粉合成酶（GBSS）的Wx基因控制。在这项研究中，16个单节置换线窝藏Wx基因从16个不同的捐助者和他们的受体HJX 74被用来检测在Wx基因座的自然发生的等位基因变异。不同环境条件下，供试材料的AAC含量差异较大，可分为糯性、低AAC、中AAC和高I AAC（24.36-25.20%）、高II AAC（25.81-26.19%）两个亚类，且与GBSS酶活性呈正相关。在Wx基因上检测到1个插入/缺失（InDel）和3个单核苷酸多态性，它们的组合导致5类AAC的变异。根据AAC表型、GBSS活性和cDNA序列分析结果，共鉴定出5个Wx等位基因：wx、Wxt、Wxg 1、Wxg 2和Wxg 3，其中Wxg 2和Wxg 3为本研究首次分离。在不同种植季节，Wxt和Wxg 1等位基因的AAC差异显著，秋季AAC高于春季，而wx、Wxg 2和Wxg 3等位基因的AAC差异不显著。总之，本研究结果可能有助于我们了解自然发生的等位基因变异的Wx位点，并将有助于通过分子标记辅助选择改善稻米品质。
Apparent amylose content (AAC) is a key determinant of eating and cooking quality in rice and it is mainly controlled by the Wx gene which encodes a granule-bound starch synthase (GBSS). In this study, sixteen single-segment substitution lines harboring the Wx gene from 16 different donors and their recipient HJX74 were used to detect the naturally occurring allelic variation at the Wx locus. The AAC in the materials varied widely and could be grouped into glutinous, low, intermediate, and two high AAC sub-classes, high I (24.36–25.20%) and high II (25.81–26.19%), under different experimental environments, which showed a positive correlation with the enzymatic activity of GBSS. One insertion/deletion (InDel) and three single nucleotide polymorphisms in the Wx gene were detected and their combinations resulted in the variation of five classes of AAC. Based on the results of AAC phenotypes, GBSS activities and cDNA sequences, five Wx alleles, wx, Wxt, Wxg1, Wxg2, and Wxg3, were identified, two of which, Wxg2 and Wxg3, are separated for the first time in this study. Under different cropping seasons, the AAC differed significantly for the Wxt and Wxg1 alleles, with higher AAC in the fall season than in the spring season, but did not differ significantly for the wx, Wxg2, and Wxg3 alleles. In conclusion, the present results might contribute to our understanding of the naturally occurring allelic variation at the Wx locus and will facilitate the improvement of rice quality by marker-assisted selection.