水稻叶宽基因qFLW7和OsNAAL1的图位克隆及其分子调控机制

发布时间：2018-04-29 00:10

本文选题：水稻 + 叶片宽度　；参考：《沈阳农业大学》2017年博士论文

【摘要】：聚合有利基因,挖掘增产潜力,寻求产量更大突破,将是水稻产业发展的重要方向。如何在分子水平通过叶形调控,协调水稻植株产量形成的"源-流-库"互作关系,提高光合效率,是保证水稻实现高产的基本前提。本研究的第一个材料是以遗传背景清晰并已完成测序的高产籼稻品种扬稻6号(93-11)和优质粳稻品种日本晴为亲本材料,在前期利用其构建重组自交系并完成抽穗期叶宽QTLqFLW7定位的基础上,分别以93-11和日本晴互为QTLqFLW7片段供体,并以各自对应的受体亲本为轮回亲本构建2个近等基因系NIL-FLW79311和NIL-FLW7NPB,开展叶宽调控基因qFLW7的克隆、功能分析及其育种利用研究。研究结果如下:1.通过93-11与日本晴重组自交系进行叶形QTL分析,位于第7染色体上的叶宽增效等位基因来自93-11,图位克隆获得叶宽QTLqFLW7。NIL-FLW793-11与轮回亲本NPB相比,叶片的小维管束数目极显著的增加,叶片宽度和叶面积都增大;而NIL-FFLW7NPB与轮回亲本93-11相比,小维管束数目则极显著减少,叶片宽度和叶面积都减小。2.在抽穗期,对两个候选基因进行相对表达量分析,LOC_Os07g41190在近等基因系NIL-FLW7NPB与其轮回亲本93-11之间的表达没有显著的差异,而NIL-FLW7NPB中LOC_Os07g41200的表达量是93-11的4.51倍。OsFLW7基因的过量表达使水稻叶宽变窄,叶面积下降;抑制OsFLW7的表达则使叶宽增加,叶面积增大;而水稻籽粒长度发育与OsFLW7表达间存在一定的平衡,无论是OsFLW7表达增加或基因功能的下降都可能导致粒长的增加。3.OsFLW7基因在调控叶片形态建成的同时,改变叶片组织结构,从而影响叶片的光合作用速率。OsFLW7功能降低可以增加水稻植株叶片受光面积,并提高叶片的光合效率。近等基因系田间产量测定试验同样证实,NIL-FLW79311籽粒长度和千粒重较NPB都极显著增加,大田实际产量增幅达10%以上,增产作用显著。本研究的另一个材料,是以EMS诱变籼稻品种蜀恢527分离获得的一个水稻窄叶白化突变体narrow-albino leaf1(naall),通过图位克隆并对叶片形态的分子调控机制研究,探索OsNsAL1基因在水稻叶片形态发育、生长素代谢调控及水稻产量形成中的重要作用。研究结果如下:1.相对野生型蜀恢527,突变体naall呈现株高变矮、窄叶且叶片上表面白化、冠根减少、叶片表面毛状体数目增多等突变表型。突变体naall的叶片近轴面和远轴面的大、小毛状体数目较野生型极显著增加;叶绿体基质片层结构数目显著减少;叶片主、次维管束的数目显著减少。2.利用图位克隆的方法,将OsNAAL1定位到水稻第7染色体上,编码一个CHR4/MI-2-like蛋白。互补试验证明LOCOs07g31450就是调控叶片宽度发育的目标基因OsNAAL1。OsNAAL1以组成型的方式在水稻根、茎、叶、鞘和穗部表达,编码一个核蛋白。3.naal 窄叶突变表型的出现,不仅与多个叶片形态发育调控基因相关,同时还与生长素合成、转运、信号传导等代谢途径相关。naall对不同浓度外源NAA处理具有响应,推测OsNAAL1可能通过参与水稻生长素的色氨酸生物合成途径,从而影响水稻根系的发育和叶片形态建成。
[Abstract]:It is an important direction for the development of rice industry to polymerized the favorable gene, excavate the potential of increasing yield and seek a greater breakthrough in production. It is the basic premise to ensure the high yield of rice at the molecular level through the regulation of leaf shape, coordinate the relationship between the source flow and reservoir of rice plant yield, and improve the photosynthetic efficiency. The first material of this study is to The high yield indica rice cultivar Yangdao No. 6 (93-11) and high quality japonica rice varieties, which have a clear genetic background and have been sequenced, are the parent materials. On the basis of the early use of the recombinant inbred line and the QTLqFLW7 location of the leaf width of the heading stage, 93-11 and Japan clear each other are QTLqFLW7 fragments, respectively, with their respective receptor parents as their parents. 2 near isogenic lines NIL-FLW79311 and NIL-FLW7NPB were constructed and the leaf width regulation gene qFLW7 was cloned, functional analysis and breeding utilization were carried out. The results were as follows: 1. the leaf width enhancement allele on the seventh chromosome from 93-11 was analyzed with the Japanese clear recombinant inbred line, and the allele of the leaf width synergistic allele on the seventh chromosome was from 93-11. The number of small vascular bundles in leaf width QTLqFLW7.NIL-FLW793-11 increased significantly compared with the recurrent parent NPB, and the leaf width and leaf area increased. While NIL-FFLW7NPB compared with the recurrent parent 93-11, the number of small vascular bundles decreased significantly, and the leaf width and leaf area decreased by.2. at the heading stage and relative to the two candidate genes. Expression analysis showed that there was no significant difference in the expression of LOC_Os07g41190 between the near isogenic line NIL-FLW7NPB and its recurrent parent 93-11, while the expression of LOC_Os07g41200 in NIL-FLW7NPB was 4.51 times of 93-11 and the overexpression of.OsFLW7 gene made the leaf width narrowed and the leaf area decreased, and the expression of the inhibition of OsFLW7 increased leaf width and increased leaf area. There is a balance between the growth of rice grain length and the expression of OsFLW7. Both the increase of OsFLW7 expression and the decrease of the gene function may lead to the increase of the grain length. The.3.OsFLW7 gene changes the leaf tissue structure while regulating the leaf morphogenesis, thus affecting the decrease of the photosynthesis rate of the leaves and the decrease of the function of.OsFLW7. The leaf area of the rice plants and the photosynthetic efficiency of the leaves were increased. The field yield test of the near isogenic lines also confirmed that the grain length and 1000 grain weight of NIL-FLW79311 increased significantly than that of NPB, and the actual yield increased by more than 10%, and the effect of increasing yield was significant. The other material of this study was to mutagenesis the indica rice variety Shu Hui 527 points by EMS. A rice narrow leaf albino mutant narrow-albino leaf1 (naall) was obtained. The important role of OsNsAL1 gene in the morphological development of rice leaves, regulation of auxin metabolism and the formation of rice yield was investigated by cloning and molecular regulation mechanism of leaf morphology. The results are as follows: 1. relative to wild type Shu Hui 527, mutants Naall showed a dwarf strain, a narrow leaf and a whitening on the upper surface of a leaf, a decrease in the crown root and an increase in the number of hairy bodies on the surface of the leaf. The mutant naall leaves the near axis and the distal axis, and the number of small hairy bodies is significantly higher than that of the wild type; the number of the lamellar structure of the chloroplast is significantly reduced, and the number of the leaf main and secondary vascular bundles is significant. Reducing.2. by using the method of graphic cloning, OsNAAL1 is located on the seventh chromosome of rice to encode a CHR4/MI-2-like protein. The complementarity test shows that LOCOs07g31450 is the expression of the target gene OsNAAL1.OsNAAL1 that regulates the leaf width development in the form of the rice root, stem, leaf, sheath and ear, and encodes a nucleoprotein.3.naal narrow leaf. The occurrence of mutant phenotype is not only related to the regulation genes of multiple leaf morphological development, but also with the response of.Naall to exogenous NAA treatment with different concentrations, such as auxin synthesis, transport, signal transduction and other metabolic pathways. It is presumed that OsNAAL1 may be involved in the tryptophan biosynthesis pathway of rice auxin, thus affecting the root development of rice. Breeding and leaf morphogenesis.

【学位授予单位】：沈阳农业大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：S511

【参考文献】