宁夏大学农学院 / 宁夏优势特色作物现代分子育种重点实验室,银川 750021
研究方向为水稻遗传育种,E-mail: 1916640220@qq.com
马天利,研究方向为水稻遗传育种,E-mail: tianlima2018@163.com
宁夏自然科学基金项目(2021AAC03086);宁夏重点研发项目引才专项(2019BEB04014)
Agricultural College, Ningxia University/Ningxia Key Laboratory of Modern Molecular Breeding for Dominant and Characteristic Crops, Yinchuan 750021
Foundation projects:Ningxia Natural Science Foundation Project (2021AAC03086); Ningxia Key R&D Project for Talent Introduction (2019BEB04014)
高抗性淀粉的稻米有益于改善人类健康并降低与饮食相关的慢性疾病风险。挖掘新的水稻籽粒抗性淀粉相关基因,对揭示水稻籽粒抗性淀粉合成的遗传机理有重要意义,同时可为选育高抗性淀粉水稻新品种提供新的基因资源。本研究以宁夏本地高产粳稻品种宁粳28号和外引粳稻品种JTD,以及构建的126个F7重组自交系(RILs, recombination inbred lines)群体为研究材料,通过全基因组重测序技术构建了一张含有1,856个Bin标记的遗传连锁图谱。该图谱全长1973.86 cM,标记间平均遗传距离为1.06 cM。采用CIM区间作图法对水稻群体的抗性淀粉性状进行QTL定位,检测到1个控制抗性淀粉的QTL,位于第7号染色体上,LOD值为4.2,贡献率为9.7%。深入分析获得候选基因Os07g0444000(预测为水稻葡萄糖神经酰胺酶)和Os07g0443500(含有MYB结构域的DNA结合蛋白)。研究发现Os07g0444400上SNP15740179和SNP15740207位点的基因型频率在RIL群体高抗性淀粉组和低抗性淀粉组之间存在显著差异。在灌浆过程中,Os07g0443500和Os07g0444000在父本JTD(高抗性淀粉亲本)中的表达量均不同程度的高于母本宁粳28号。由此推测这两个候选基因可能参与水稻籽粒灌浆过程中抗性淀粉的形成。本研究通过挖掘水稻籽粒抗性淀粉QTL位点和相关基因为选育高抗性淀粉水稻新品种提供新的基因资源。
Functional rice with high resistant starch content improves human health considering the risk of diet-related chronic diseases. Exploring the resistant starch-related genes is of great significance to reveal the genetic mechanism of rice grain resistant starch synthesis, which has implication in breeding rice varieties with high resistant starch. In this study, 126 F7 recombinant inbred lines (RILs) from cross between Ningxia local high-yield japonica rice variety Ningjing 28 and imported japonica rice variety JTD were used. A genetic linkage map containing 1,856 Bin markers was constructed by whole genome resequencing technology, showing a length of 1973.86 cM, and the average genetic distance of 1.06 cM between markers. Using CIM interval mapping method to map the QTL of resistant starch traits in rice populations, one QTL controlling resistant starch was detected on chromosome 7, with a LOD value of 4.2 and a contribution rate of 9.7%. Through in-depth analysis, two candidate genes Os07g0444000 (predicted as rice glucosylceramidase) and Os07g0443500 (DNA binding protein containing MYB domain) were obtained. The study found that the genotype frequencies of SNP15740179 and SNP15740207 on Os07g0444400 were significantly different between the high resistant starch group and the low resistant starch group in the RIL population. During the grain filling process, the expression levels of Os07g0443500 and Os07g0444000 in the male parent JTD(high resistant starch parent) were higher than those of the female parent Ningjing 28. These results implied that both candidate genes may be involved in forming resistant starch during rice grain filling. Collectively, this study provides new genetic resources for the breeding of new rice varieties with high resistant starch by mining the QTL loci and related genes of rice grain-resistant starch.
张风琴,于雪然,李玲,等.基于高密度遗传图谱对水稻抗性淀粉