水稻多效性基因Ghd7.1的克隆與功能分析
發(fā)布時間：2018-08-03 21:07
【摘要】：水稻是我國的主要糧食作物之一,高產(chǎn)和穩(wěn)產(chǎn)一直是水稻科技人員的主要追求目標。利用圖位克隆的方法鑒定水稻高產(chǎn)基因,不僅可以解析水稻產(chǎn)量構(gòu)成機制,還可以直接指導(dǎo)水稻分子設(shè)計育種。水稻是典型的短日照植物,以13.5h為臨界點,在日照長度短于13.5h時提前開花,長于13.5h時延遲開花。前期利用汕優(yōu)63的母本珍汕97與高產(chǎn)品種特青構(gòu)建重組自交系,在該自交系中檢測到一個可以同時延遲抽穗,增加株高和產(chǎn)量的多效性位點,該位點位于第7染色體末端,故將其命名為Ghd7.1(grain number,plant height and heading date)。本研究通過構(gòu)建珍汕97為受體/特青為供體的Ghd7.1近等基因系,對Ghd7.1的表型進行了確認:特青等位基因型為顯性,長日照條件下,表現(xiàn)為延遲抽穗19天,增加株高28cm,增產(chǎn)幅度超過60%。通過8h,10h和自然長日照條件下種植近等基因系并考察表型,發(fā)現(xiàn)Ghd7.1是一個光周期敏感的抽穗期基因,僅在長日照條件下抑制抽穗期,短日照條件下無抽穗期表型差異,但是有微弱的株高和產(chǎn)量的表型差異。主莖穗考種顯示株高增加是因為在特青等位基因型中莖節(jié)增加一節(jié),同時每個莖節(jié)長度也顯著長于珍汕97等位基因型對應(yīng)的的莖節(jié)長度。對主莖穗的穗長、一次枝梗,二次枝梗和每穗穎花數(shù)等性狀進行考察,發(fā)現(xiàn)特青等位基因型在上述性狀也都顯著增加,最終導(dǎo)致產(chǎn)量大幅度提高。在組織水平,通過對近等基因系幼穗進行動態(tài)觀察,比較兩種等位基因型的分化歷時和分化速率,發(fā)現(xiàn)Ghd7.1是通過延長分化歷時增加每穗穎花數(shù)。利用圖位克隆的方法對該基因進行了克隆,發(fā)現(xiàn)Ghd7.1編碼一個PRR(PSEUDO-RESPONSE REGULATORS)類的蛋白,具有一個REC domain(response receivers domain)和一個CCT domain(CONSTANS,CO-like,and TOC1domain),亞細胞定位顯示Ghd7.1定位于細胞核。在擬南芥中,Ghd7.1的同源基因AtPRR7是生物鐘核心振蕩器的組份之一,通過生物鐘來調(diào)控開花。而對Ghd7.1的近等基因系進行光周期處理,發(fā)現(xiàn)Ghd7.1并不影響水稻生物鐘,而是通過抑制水稻特有的基因Ehd1來調(diào)控水稻抽穗期。通過對178份種質(zhì)資源品種的重測序我們一共鑒定出24種等位基因型,結(jié)合關(guān)聯(lián)分析共鑒定出7種無功能的等位基因型。粳稻中最主要的等位基因型是日本晴等位基因型,利用近等基因系進行了不同等位基因的效應(yīng)評價,發(fā)現(xiàn)與特青等位基因型相比,日本晴等位基因型是一種弱等位基因型。進一步通過對47份野生稻的比較測序,未檢測到無功能的等位基因型,暗示Ghd7.1是一個在水稻馴化中被保留下來的基因,并且秈稻和粳稻的主要基因型都可以在野生稻中找到序列完全一致的基因型,推斷Ghd7.1秈稻和粳稻的等位基因型是獨立起源于野生稻。進一步構(gòu)建Ghd7.1序列上的進化流程圖,發(fā)現(xiàn)其在水稻適應(yīng)性和擴散過程中的重要貢獻:Ghd7.1由野生稻的有功能到栽培稻的無功能等位基因型的進化歷程,正是水稻能夠由低緯度向高緯度擴散的重要推動力,同時通過Ghd7.1功能缺失后抽穗期短,育種家培育出生育期很短的品種在部分地區(qū)種植雙季稻,提高農(nóng)田利用效率。
[Abstract]:Rice is one of the main grain crops in China. High yield and stable yield have always been the main pursuit of rice science and technology personnel. The identification of high yield gene of rice by the method of map cloning can not only analyze the mechanism of rice yield, but also direct the rice molecular design and breeding. Rice is a typical short day plant with 13.5h as the critical point. When the length of sunshine is shorter than 13.5h, it blooms ahead of time and delays flowering when it is longer than 13.5h. In the early stage, a recombinant inbred line was constructed with the mother of Shanyou 63, the mother of Shanyou 97 and the high yield variety special green. In the inbred line, a pleiotropic location that could delay the heading, increase plant height and yield was detected at the end of the seventh chromosome. Ghd7.1 (grain number, plant height and heading date). In this study, the phenotype of Ghd7.1 was confirmed by constructing a Ghd7.1 near isogenic line with a receptor / special green as a donor. The special green allele was dominant. Under long sunshine conditions, the phenotype was delayed for 19 days and increased the plant height, and the increase of yield was more than that of 60%.. It is found that Ghd7.1 is a photoperiod sensitive gene of heading stage, which is a photoperiod sensitive gene, which only inhibits heading stage under long sunshine conditions and has no heading phase difference under short sunshine conditions, but there is a weak phenotype difference between plant height and yield. In the green allele, the stem node was increased by one node, and the length of each stem segment was significantly longer than that of the Jen Shan 97 allele. The spike length of the main stem, the primary branch, the two branch and the spikelet number per panicle were investigated. It was found that the special green allele also increased significantly in the above characters, which eventually led to a large yield. At the organizational level, the differentiation diachronic time and differentiation rate of the two alleles were compared by the dynamic observation of the near isogenic lines, and the number of spikelet number per panicle was increased by prolonging the differentiation period. The gene was cloned by the method of graph cloning, and Ghd7.1 was found to encode a PRR (PSEUDO-RESPONSE REGULA). TORS) proteins that have a REC domain (response receivers domain) and a CCT domain (CONSTANS, CO-like, and TOC1domain), which are located in the nucleus. In Arabidopsis, the homologous gene is one of the components of the core oscillator in the biological clock. The near isogenic lines were treated with photoperiod. It was found that Ghd7.1 did not affect the rice biological clock, but by inhibiting rice specific gene Ehd1 to regulate the heading stage of rice. By resequencing 178 germplasm resources, we identified 24 alleles, and identified 7 non functional allelic genotypes combined with correlation analysis. The main allele of the rice is the Japanese clear allele, and the effect of different alleles is evaluated using the near isogenic lines. It is found that the Japanese clear allele is a weak allele compared with the special green allele, and the non functional allele is not detected by the comparison of 47 wild rice sequences. Type, suggesting that Ghd7.1 is a gene preserved in rice domestication, and the major genotypes of both indica and japonica rice can be found in wild rice with a complete sequence of genotypes. It is concluded that the allelic genotypes of Ghd7.1 indica and japonica are independently derived from wild rice. The evolutionary flow chart of the Ghd7.1 sequence is constructed step by step. The important contribution in the process of rice adaptation and diffusion: the evolutionary course of Ghd7.1 from the functional to the non functional allele of cultivated rice is the important driving force for rice to spread from low latitudes to high latitudes. At the same time, the breeders cultivate short breeds at birth by the lack of Ghd7.1 function. Double cropping rice is planted in different regions to improve the efficiency of farmland utilization.
【學(xué)位授予單位】：華中農(nóng)業(yè)大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2016
【分類號】：S511;Q943.2
本文編號：2162999
[Abstract]:Rice is one of the main grain crops in China. High yield and stable yield have always been the main pursuit of rice science and technology personnel. The identification of high yield gene of rice by the method of map cloning can not only analyze the mechanism of rice yield, but also direct the rice molecular design and breeding. Rice is a typical short day plant with 13.5h as the critical point. When the length of sunshine is shorter than 13.5h, it blooms ahead of time and delays flowering when it is longer than 13.5h. In the early stage, a recombinant inbred line was constructed with the mother of Shanyou 63, the mother of Shanyou 97 and the high yield variety special green. In the inbred line, a pleiotropic location that could delay the heading, increase plant height and yield was detected at the end of the seventh chromosome. Ghd7.1 (grain number, plant height and heading date). In this study, the phenotype of Ghd7.1 was confirmed by constructing a Ghd7.1 near isogenic line with a receptor / special green as a donor. The special green allele was dominant. Under long sunshine conditions, the phenotype was delayed for 19 days and increased the plant height, and the increase of yield was more than that of 60%.. It is found that Ghd7.1 is a photoperiod sensitive gene of heading stage, which is a photoperiod sensitive gene, which only inhibits heading stage under long sunshine conditions and has no heading phase difference under short sunshine conditions, but there is a weak phenotype difference between plant height and yield. In the green allele, the stem node was increased by one node, and the length of each stem segment was significantly longer than that of the Jen Shan 97 allele. The spike length of the main stem, the primary branch, the two branch and the spikelet number per panicle were investigated. It was found that the special green allele also increased significantly in the above characters, which eventually led to a large yield. At the organizational level, the differentiation diachronic time and differentiation rate of the two alleles were compared by the dynamic observation of the near isogenic lines, and the number of spikelet number per panicle was increased by prolonging the differentiation period. The gene was cloned by the method of graph cloning, and Ghd7.1 was found to encode a PRR (PSEUDO-RESPONSE REGULA). TORS) proteins that have a REC domain (response receivers domain) and a CCT domain (CONSTANS, CO-like, and TOC1domain), which are located in the nucleus. In Arabidopsis, the homologous gene is one of the components of the core oscillator in the biological clock. The near isogenic lines were treated with photoperiod. It was found that Ghd7.1 did not affect the rice biological clock, but by inhibiting rice specific gene Ehd1 to regulate the heading stage of rice. By resequencing 178 germplasm resources, we identified 24 alleles, and identified 7 non functional allelic genotypes combined with correlation analysis. The main allele of the rice is the Japanese clear allele, and the effect of different alleles is evaluated using the near isogenic lines. It is found that the Japanese clear allele is a weak allele compared with the special green allele, and the non functional allele is not detected by the comparison of 47 wild rice sequences. Type, suggesting that Ghd7.1 is a gene preserved in rice domestication, and the major genotypes of both indica and japonica rice can be found in wild rice with a complete sequence of genotypes. It is concluded that the allelic genotypes of Ghd7.1 indica and japonica are independently derived from wild rice. The evolutionary flow chart of the Ghd7.1 sequence is constructed step by step. The important contribution in the process of rice adaptation and diffusion: the evolutionary course of Ghd7.1 from the functional to the non functional allele of cultivated rice is the important driving force for rice to spread from low latitudes to high latitudes. At the same time, the breeders cultivate short breeds at birth by the lack of Ghd7.1 function. Double cropping rice is planted in different regions to improve the efficiency of farmland utilization.
【學(xué)位授予單位】：華中農(nóng)業(yè)大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2016
【分類號】：S511;Q943.2
【相似文獻】
相關(guān)期刊論文 前1條
1 ;我國分離出控制水稻產(chǎn)量和生育期的多效性基因[J];生物學(xué)通報;2008年06期
相關(guān)博士學(xué)位論文 前1條
1 劉海洋;水稻多效性基因Ghd7.1的克隆與功能分析[D];華中農(nóng)業(yè)大學(xué);2016年
，本文編號：2162999
本文鏈接：http://sikaile.net/shoufeilunwen/nykjbs/2162999.html
最近更新
教材專著
