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Regulation and Function of Hemoglobin in Barley Aleurone Tissue Regulation and function of hemoglobin in barley aleurone tissue A thesis Subrritted to the Faculty of Graduate Studies The University of Manitoba by Xianzhou Nie In Partial Fulfilment of the Requirernent of the Degree of Doctor of Philosophy Department of Plant Science September 1 997 National Library Bibliothèque nationale i+lof Canada du Canada Acquisitions and Acquisitions et Bibliagraphic Services services bibliographiques 395 Wellington Street 395, nie Wellington Otfawa ON KiA ON4 -ON KlAON4 Canada Canada Yournb Votm &w>a Our &? Nom nlhirence The author has granted a non- L'auteur a accordé une licence non exclusive licence dowing the exclusive permettant a la National Library of Canada to Bibliothèque nationale du Canada de reproduce, loan, distribute or sell reproduire, prêter, distribuer ou copies of this thesis in microform, vendre des copies de cette thèse sous paper or electronic fomats . la forme de microfiche/film, de reproduction sur papier ou sur format électronique. The author retains ownership of the L'auteur conserve la propriété du copyright in this thesis. Neither the droit d'auteur qui protège cette thèse. thesis nor substantial extracts korn it Ni la thèse ni des extraits substantiels may be printed or otherwise de celle-ci ne doivent être imprimés reproduced without the author's ou autrement reproduits sans son permission. autorisation. FACULTY OF GUDUATE STUDES **a** COPYRIGHT PERiWSSION PAGE A TbesidPracticum submitted to the Faculty of Graduate Studies of The University of Manitoba in partial fuliillment of the requirements of the degree of Xianzhou Nie 1997 (c) Permission has been granted to the Libnry of The University of Manitoba to lend or sel1 copies of this thesidpracticum, to the National Library of Canada to microfilm this thesis and to lend or seil copies of the film, rad to Dissertations Abstncts International to publisb an abstract of this thesidpracticum. The author reserves other publication rights, and neithet thW thesidpracticum oor extensive extracts from it may be printed or otherwise reproduced without the author's written permission. I would Wce to th& Dr. Robert D. Hiil, my advisor, for his continuous encouragement, thorough support and excellent guidance; Drs. Harry W. Duckworth (Department of Chemistry) and J. Kevin Vessey for their consultation and guidance; Drs. G. Murray Baliance and AUen G. Good (University of Aiberta, Canada) for their critical reading of the manuscript. I would also Like to thank: ali current members of Dr. HiU's laboratory, particulariy Mr. Douglas Dumin, Drs. Stephen Duff and Phillip Guy, Mr. Aleksander Sowa and Ms. Iieana Silva-Cardenas for their helpful discussion and consultation; Drs. Michel Penas and Euan R. Taylor, former postdoctorai feliows of Dr. Hill's laboratory, for their consultation; Mr. Bert Luit of the Department of Plant Science for his technicai help in the gas mixing system. My de,Cuijuan (Jan), has given me fuily wpport and encouragement. 1 thank you. To Wendy, my daughter, who makes me happy whenever 1 feel hstrated, 1 thank you. Table of Contents ... List of Abbreviations ............................................................................................................ wu List of Tables ..............................................................................................................................x List of Figures ........................................................................................................................... xi ... Abstract ................................................................................................................................... xui 1. Objectives of the research .......................................................................................................1 2. Literature Review.................................................................................................................... 3 2.1. Hemoglobin ............................................................................................................. 3 2.1.1. introduction ............................................................................................... 3 2.1.2. General aspects of hemoglobin ................................................................... 3 2.1.3. Distribution of Hb in nature ....................................................................... 5 2.1.4. Plant hemoglobin ....................................................................................... 6 2.1.4.1. Legume hemoglobin .................................................................... 6 2.1.4.1.1. Symbiotic hemoglobin ................................................... 6 2.1.4.1.2. Non-symbiotic hemoglobin ........................................... 8 2.1.4.2. Hemoglobin in non-legume dicotyledonous plants ........................ 8 2.1 A2.1. Symbiotic hemoglobin in non-Ieguminous plants ...........8 2.1 A.2.2. Non-symbio tic hemoglobin in non-legume dicots ......... 10 2.1.4.3. Hemoglobin in monocotyledonous plants ....................................10 2.1.5. Functions of hemoglobin .......................................................................... 11 2.1 .5 .1 . Hemoglobin mediated oxygen difhision and oxygen storage ....... 12 2.1 S.2. Oxygen sensing ......................................................................... 13 lu... 2.1.5.3. Other Functions .........................................................................14 2.1.6. Hemoglobin gene expression and its regdation .......................................-16 2.1.7. Evolution of hemoglobin .......................................................................16 2.2. Anaero bic responses in plants ................................................................................-19 2.2.1. Anaero bic meta bolism ............................................................................. -20 2.2.2. Molecular aspects of plants in response to anaerobic stress .......................22 2.2.3. Anaerobiosis tolerance of plants ..............................................................-26 2.3. Mitochondrial respiration ....................................................................................... 29 2.3.1. Plant mitochondrial electron transport and oxidative phosphory lation ...... 30 2.3.2. Respiratory inhibitors ............................................................................... 33 2.3.3. Energy metabolism in plants .................................................................... -35 . 2.4. Signal Transduction ui plants ................................................................................... 37 2.4.1. Ca2'/caM in signal transduction .............................................................. -38 2.4.2. Role of reversible protein phosphorylation in signal transduction in plants41 2.4.3. G-protein and signal transduction in plants ...............................................44 3. Matenals and Methods ..........................................................................................................46 3.1. Plant Materials ....................................................................................................... 46 3.1.1. Barley aleurone layers .............................................................................. 46 3.1.2. Barley coleoptiles ......; .............................................................................. 46 3.1.3. Barley seedlings .......................................................................................47 3.1.4. Rice plants ................................................................................................47 3.1.5. Other plant materials .................................................................................47 iv 3.2. Inhibitor experiments .............................................................................................-47 ... 3.2.1. Respiratory inhibitors ................................................................................47 3.2.2. Calcium and calcium inhibitors (EGTA, A23 187, ruthenium red) .............48 3.2.3. CaM antagonist, protein phosphatase and kinase inhibitors (W.7, okadaic acid and A3) ...........................................................................................49 3.2.4. Hb in hibitors ............................................................................................ 49 3.2.5. Nitrate ....................................................................................................-49 3.3. Anaerobic treatrnents.............................................................................................. -50 3.3.1 Barley aleurone layers .............................................................................. SO 3.3.2. Barley coleoptiles ..................................................................................... 50 3.3.3. Barley and maize seedlings (flooding; anoxia)........................................... 50 3.4. Southem bloning .................................................................................................... 51 3.4.1. DNA isolation .................................................................................... 1 3.4.2. Probe preparation ....................................................................................52 3.4.3. DNA hybridization ...................................................................................52 3.5. Nonhem Blotting ...................................................................................................53 3.5.1. RNA isolation
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