Wan Tai Fung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 102-111). / Abstracts in English and Chinese. / Thesis committee --- p.i / Statement --- p.ii / Abstract --- p.iii / Chinese Abstract --- p.v / Acknowledgements --- p.vii / General Abbreviations --- p.ix / Abbreviations of Chemicals --- p.xi / Table of Contents --- p.xii / List of Figures --- p.xvi / List of Tables --- p.xvi / Chapter 1 --- Literature Review --- p.1 / Chapter 1.1 --- Soybeans --- p.1 / Chapter 1.1.1 --- Nutrient composition of soybean --- p.1 / Chapter 1.1.2 --- Nitrogen fixation and assimilation in soybean --- p.3 / Chapter 1.1.3 --- The role in nitrogen allocation and controlling the nitrogen sink-source relationship of asparagine --- p.3 / Chapter 1.1.4 --- Characterization of asparagine synthetase --- p.8 / Chapter 1.1.4.1 --- Biochemistry and molecular background of plant asparagine synthetase --- p.8 / Chapter 1.1.4.2 --- Asparagine synthetase in Arabadopsis thaliana --- p.9 / Chapter 1.1.4.3 --- "Asparagine synthesis in soybean, Glycine max" --- p.10 / Chapter 1.1.4.4 --- "Asparagine synthetase in rice, Oryza sativa" --- p.11 / Chapter 1.2 --- Seed protein quality and quantity improvement --- p.13 / Chapter 1.2.1 --- Nutrition composition of rice --- p.13 / Chapter 1.2.2 --- Molecular approaches for improving seed storage protein quality --- p.14 / Chapter 1.2.2.1 --- Protein sequence modification --- p.14 / Chapter 1.2.2.2 --- Synthetic genes --- p.16 / Chapter 1.2.2.3 --- Overexpression of homologous genes --- p.17 / Chapter 1.2.2.4 --- Transfer and expression of heterologous genes --- p.18 / Chapter 1.2.2.5 --- "Manipulation of pathway synthesizing essential amino acids, aspartate family amino acid" --- p.19 / Chapter 1.2.3 --- Research in improving rice seed protein quality and quantity --- p.22 / Chapter 1.3 --- Hypothesis and objective of this study --- p.23 / Chapter 2 --- Materials and Methods --- p.25 / Chapter 2.1 --- Materials --- p.25 / Chapter 2.1.1 --- Plant materials --- p.25 / Chapter 2.1.2 --- Bacterial strains and vectors --- p.26 / Chapter 2.1.3 --- Growth conditions for soybean --- p.26 / Chapter 2.1.4 --- Chemicals and reagents --- p.26 / Chapter 2.1.5 --- "Buffer, solution and gel" --- p.26 / Chapter 2.1.6 --- Commercial kits --- p.27 / Chapter 2.1.7 --- Equipments and facilities used --- p.27 / Chapter 2.1.8 --- Primers --- p.27 / Chapter 2.2 --- Methods --- p.28 / Chapter 2.2.1 --- Growth condition for plant materials --- p.28 / Chapter 2.2.1.1 --- General conditions for planting soybean --- p.28 / Chapter 2.2.1.2 --- Soybean seedlings for gene expression profile analysis --- p.28 / Chapter 2.2.1.3 --- Mature soybean for gene expression profile analysis --- p.29 / Chapter 2.2.1.4 --- Mature soybean for cloning of AS I and AS2 full length cDNA --- p.30 / Chapter 2.2.1.5 --- Mature soybean seed for amino acid profile analysis --- p.30 / Chapter 2.2.1.6 --- General conditions for planting transgenic rice in CUHK --- p.30 / Chapter 2.2.1.7 --- Transgenic rice seedling for PCR screening --- p.31 / Chapter 2.2.1.8 --- Transgenic rice for functional test and seed for biochemical analysis --- p.31 / Chapter 2.2.2 --- Molecular techniques --- p.32 / Chapter 2.2.2.1 --- Total RNA extraction --- p.32 / Chapter 2.2.2.2 --- Denaturing gel electrophoresis for RNA --- p.33 / Chapter 2.2.2.3 --- Northern blot analysis --- p.33 / Chapter 2.2.2.3.1 --- Chemiluminescent detection --- p.33 / Chapter 2.2.2.3.2 --- Film development --- p.34 / Chapter 2.2.2.4 --- Preparation of single-stranded DIG-labeled PCR probes --- p.34 / Chapter 2.2.2.4.1 --- Primer design for the PCR probes of --- p.34 / Chapter 2.2.2.4.2 --- Amplification of AS1 and AS2 internal PCR fragments --- p.34 / Chapter 2.2.2.4.3 --- Quantitation of purified AS1 and AS2 PCR fragments --- p.35 / Chapter 2.2.2.4.4 --- Biased PCR to make single-stranded DNA probes --- p.35 / Chapter 2.2.2.4.5 --- Probe quantitation --- p.36 / Chapter 2.2.2.5 --- Probe specificity test --- p.37 / Chapter 2.2.2.6 --- Cloning of full length cDNA --- p.37 / Chapter 2.2.2.6.1 --- First strand cDNA synthesis from RNA of high protein content soybean leaf --- p.37 / Chapter 2.2.2.6.2 --- PCR for amplification of AS1 and AS2 full length cDNA --- p.38 / Chapter 2.2.2.6.3 --- Preparation of pBluescript II KS(+) T-vector for cloning --- p.38 / Chapter 2.2.2.6.4 --- Ligation of DNA inserts into pBluescript II KS(+) T-vector --- p.39 / Chapter 2.2.2.6.5 --- Preparation of E. coli DH5α CaCl2-mediaed competent cells --- p.39 / Chapter 2.2.2.6.6 --- Transformation of E. coli DH5α competent cell --- p.40 / Chapter 2.2.2.7 --- Screening of recombinant plasmids --- p.40 / Chapter 2.2.2.7.1 --- Isolation of recombinant plasimid DNA from bacterial cells --- p.41 / Chapter 2.2.2.7.2 --- PCR screening on recombinant plasmids --- p.41 / Chapter 2.2.2.7.3 --- DNA gel electrophoresis --- p.41 / Chapter 2.2.2.8 --- Sequencing and homology search --- p.42 / Chapter 2.2.2.9 --- Functional test using transgenic plant --- p.43 / Chapter 2.2.2.9.1 --- Preparation of chimeric gene constructs and recombinant plasmids --- p.43 / Chapter 2.2.2.9.2 --- Agrobacterium mediated transformation into rice calli to regenerate transgenic AS1/ AS2 rice --- p.44 / Chapter 2.2.2.10 --- PCR Screenig of homozygous and heterozygous transgenic plants --- p.44 / Chapter 2.2.2.10.1 --- Isolation of genomic DNA from transgenic plants --- p.45 / Chapter 2.2.2.10.2 --- PCR screening using genomic DNA --- p.46 / Chapter 2.2.2.11 --- Quantitative PCR analysis on transgenic plants --- p.48 / Chapter 2.2.3 --- Biochemical Analysis --- p.49 / Chapter 2.2.3.1 --- Quantitative amino acid analysis in mature soybean seeds --- p.49 / Chapter 2.2.3.2 --- Quantitative amino acid analysis in mature transgenic rice grain --- p.49 / Chapter 3 --- Results --- p.50 / Chapter 3.1 --- Amino acid analysis on mature soybean seeds --- p.50 / Chapter 3.2 --- Expression pattern analysis of AS genes by Northern Blot analysis --- p.54 / Chapter 3.2.1 --- Making of single strand digoxigenin (DIG)-labeled probe --- p.54 / Chapter 3.2.2 --- Probe specificity --- p.57 / Chapter 3.2.3 --- AS expression level under light/dark treatments by Northern Blot analysis --- p.58 / Chapter 3.2.4 --- AS expression level in young seedlings by Northern Blot analysis --- p.62 / Chapter 3.2.5 --- AS expression level in podding soybean by Northern Blot analysis --- p.64 / Chapter 3.3 --- Cloning of AS genes from high protein content soybeans --- p.66 / Chapter 3.3.1 --- "PCR amplification of AS1 and AS2 full length cDNA from the first-strand cDNA of high portein content cultivar soybean, YuDoul2" --- p.66 / Chapter 3.3.2 --- Nucleotide sequences analysis of AS1 and AS2 full-length cDNA clones --- p.68 / Chapter 3.4 --- Construction of AS1 and AS2 transgenic rice --- p.75 / Chapter 3.4.1 --- Construction of AS1 and AS2 constructs --- p.75 / Chapter 3.4.2 --- Transformation of chimeric gene constructs into Agrobacterium tumefaciens --- p.75 / Chapter 3.4.3 --- Agrobacterium mediated transformation into Oryza sativa calli to regenerate transgenic rice --- p.76 / Chapter 3.4.4 --- PCR screening of transgene from transgenic AS1 and AS2 rice --- p.76 / Chapter 3.4.5 --- Quantitative PCR analysis of the transgene expression --- p.81 / Chapter 3.4.6 --- Quantitative amino acid analysis in mature transgenic rice grain --- p.83 / Chapter 4 --- Discussion --- p.89 / Chapter 4.1 --- The role of asparagine and asparagine synthetase in nitrogen assimilation and sink-source relationship in soybean --- p.89 / Chapter 4.2 --- Comparative study of AS between different high seed protein content crops --- p.92 / Chapter 4.3 --- The attempt to find out the reason for the strong AS1 expression detected in high protein soybean cultivars --- p.92 / Chapter 4.4 --- Other factors affecting seed protein contents --- p.93 / Chapter 4.5 --- Rice seed quality improvement by nitrogen assimilation enhancement --- p.94 / Chapter 4.6 --- Comparative study of amino acid profile and seed total protein in other transgenic rice --- p.95 / Chapter 4.7 --- Possible reason of higher seed protein content in AS2 transgenic rice --- p.96 / Chapter 4.8 --- Selectable marker --- p.97 / Chapter 5 --- Conclusion and Prespectives --- p.99 / Chapter 6 --- References --- p.102 / Chapter 7 --- Appendix --- p.112 / Appendix I: Major chemicals and reagents used in this research --- p.112 / "Appendix II: Major buffer, solution and gel used in this research" --- p.114 / Appendix III: Commercial kits used in this research --- p.117 / Appendix IV: Major equipments and facilities used in this research --- p.118 / Appendix V: Primer list --- p.119