植物中存在各種各樣的修飾化反應(yīng),能夠產(chǎn)生大量結(jié)構(gòu)多樣性的代謝物,這些反應(yīng)通常能夠改變這些代謝物前體的生物學(xué)功能。糖基轉(zhuǎn)移酶介導(dǎo)的糖基化反應(yīng)是引起次生代謝物多樣性的主要反應(yīng)之一。類黃酮是一類廣泛存在于植物體內(nèi)的次生代謝產(chǎn)物,在植物的生長(zhǎng)發(fā)育過(guò)程中發(fā)揮至關(guān)重要的作用。盡管黃酮醇（類黃酮的一個(gè)分支）在模式植物擬南芥中已經(jīng)被廣泛研究,其代謝途徑的調(diào)控也比較清楚,但是作為類黃酮的另外一個(gè)分支,黃酮以及由糖基轉(zhuǎn)移酶合成的糖基化的產(chǎn)物卻鮮有報(bào)道。這些代謝物在模式作物如水稻中的自然變異仍待解析。在本研究中,我們解析了水稻中黃酮的自然變異及其遺傳和生化基礎(chǔ)。通過(guò)液質(zhì)聯(lián)用技術(shù),結(jié)合廣泛靶向的檢測(cè)方法,我們測(cè)定了7個(gè)囊括原始被子植物、單子葉、雙子葉等不同植物葉片中包括黃酮、黃酮醇和黃烷酮在內(nèi)的類黃酮代謝譜。檢測(cè)結(jié)果表明糖基化黃酮的積累具有物種特異性,在單子葉植物例如水稻中含量很高,這一特點(diǎn)正好為后續(xù)解析水稻中黃酮的自然變異提供便利。另外,基于代謝物的全基因組關(guān)聯(lián)分析方法鑒定了三個(gè)水稻中控制黃酮糖基化的主要位點(diǎn),這些位點(diǎn)分布在第1和5號(hào)染色體上。在這些位點(diǎn)內(nèi)部的糖基轉(zhuǎn)移酶被認(rèn)為是控制水稻類黃酮自然變異的候選基... 

【文章來(lái)源】：華中農(nóng)業(yè)大學(xué)湖北省 211工程院校 教育部直屬院校

【文章頁(yè)數(shù)】：127 頁(yè)

【學(xué)位級(jí)別】：博士

【文章目錄】：
Abstract
摘要
Abbreviations
CHAPTER I Introduction
    1.1. Plant metabolites: An overview
    1.2. The rise of chemical diversity in plant species
    1.3. Modification reactions contribute to metabolic diversity in plant species
    1.4. Glycosylation and glycosyltransferases
    1.5. The flavonoid glycosyltransferases (Flavonoid UGTs)
    1.6. Flavonoid biosynthesis and key genes involved in the pathway
    1.7. Identification and functional characterization of flavonoid UGTs
        1.7.1. Flavonoid 3-O-glycosyltransferases (F3GTs)
        1.7.2. Flavonoid 5-O-glycosyltransferases (F5GTs)
        1.7.3. Flavonoid 7-O-glycosyltransferases (F7GTs)
        1.7.4. Flavonoid 3′-O-glycosyltransferases (F3′GTs)
        1.7.5. Falvoniod C-glycosyltransferases (CGTs)
        1.7.6. Flavonoid glycoside glycosyltransferases (GGTs)
    1.8. Biological role of flavonoids in protection against stresses
    1.9. ‘Omics’ assisted integrated strategies determine gene-metabolite regulatorynetwork and led to gene function in plants
        1.9.1. Metabolite profiling manifest a powerful tool for large-scale metaboliteidentification in plants
        1.9.2. Metabolic genome-wide association in plants and its implication in functionalgenomics
    1.10. Towards our research interests
CHAPTER Ⅱ Material and methods
    2.1. Plant materials and metabolite profiling
    2.2. Nomenclature of glucosyltransferase (UGT) encoding genes
    2.3. Genome-wide association mapping by gene-based analysis
    2.4. Phylogenetic tree construction and analysis
    2.5. Rice UGT genes cloning and vector construction
    2.6. Recombinant protein expression analysis
    2.7. Enzyme activity assays
    2.8. Enzyme kinetics
    2.9. Rice transformation, gene expression analysis by q RT-PCR and targetedmetabolites assessment in transgenic plants
        2.9.1. Overexpression vector constructs and transformation into rice
        2.9.2. Quantitative RT-PCR analysis
        2.9.3. Quantification and analysis of flavonoids in Os UGT706D1 overexpressionplants
    2.10. Bioinformatics approaches and analyses
        2.10.1. Genebank accession numbers used in phylogentic trees construction
        2.10.2. Gene structures and characterization of the conserved PSPG motif ofOs UGTs
        2.10.3. Os UGT706D1 protein 3D-structural model generation
    2.11. Statistical analysis
Chapter Ⅲ Results
    3.1. Flavonoid profiling among plant species
    3.2. Genetic control of natural variation of rice flavonoids
    3.3. Phylogenetic characterization of putative rice flavonoid UGTs
    3.4. Molecular cloning of the candidate rice flavonoid UGT genes
    3.5. Biochemical characterization of putative flavonoid UGTs
        3.5.1. In vitro enzymatic activities of flavonol UGTs
        3.5.2. In vitro enzymatic activities of flavone UGTs
    3.6. Activities of flavone UGTs in vivo
    3.7. Functional polymorphisms behind the variation of major rice flavones
    3.8. Evolutionary and comparative genomic insights into flavonoid UGTs
ChapterⅣ Discussion
    4.1. Widely-targeted metabolomics strategy facilitates identification and quantificationof secondary metabolites in plant species
    4.2. Metabolite-based genome-wide association study (m GWAS) aids understandingsinto the genetic basis of flavonoids metabolism in rice
    4.3. Forward and reverse genomics approaches together disclose the in vitrobiochemical and in planta functions of flavonoid UGT genes
    4.4. Functional genetic polymorphisms contribute to the natural variation of majorflavonoid contents in rice
    4.5. Inferring the evolutional history of major flavonoid UGT genes provides signaturesinto their conserved evolution
    4.6. Conclusion and future directions
References
Appendices
    Appendix 1 Flavonoid profiling among 7 plant species
    Appendix 2 LC-MS based flavonoid profiling in Arabidopsis
    Appendix 3 Genetic control of the natural variation for the flavonoid traits
    Appendix 4 Manhattan plots of the m GWAS result for the flavonoid traits
    Appendix 5 Single nucleotide polymorphisms (SNPs) behind the natural variation of flavone 7-O-glucosides (Os UGT706D1)
Brief history of author
List of publications
Acknowledgement


【參考文獻(xiàn)】：
期刊論文
[1]Novel Natural Allelic Variations at the Rht-1 Loci in Wheat[J]. Aixia Li,Wenlong Yang,Xueyuan Lou,Dongcheng Liu,Jiazhu Sun,Xiaoli Guo,Jing Wang,Yiwen Li,Kehui Zhan,Hong-Qing Ling,Aimin Zhang.  Journal of Integrative Plant Biology. 2013(11)



本文編號(hào)：3180637