caa a22 4500 397521170 CHVBK 20180308164633.0 cr unu---uuuuu 161202e199509 xx s 000 0 eng 10.1093/jxb/46.special_issue.1309 doi (NATIONALLICENCE)oxford-10.1093/jxb/46.special_issue.1309 Manipulation of phosphoribulokinase and phosphate translocator activities in transgenic tobacco plants [Elektronische Daten] [John C. Gray, Matthew J. Paul, Simon A. Barnes, Jacqueline S. Knight, Andrew Loynes, Dimah Habash, Martin A.J. Parry, David W. Lawlor] Transgenic tobacco plants containing altered amounts of phosphoribulokinase (PRK) and the chloroplast phosphate translocator (PT) have been produced by transformation with tobacco cDNAs in the sense or antisense orientation expressed from a tobacco rbcS promoter. Plants expressing antisense PRK RNA contained a range of PRK activities from wild type to less than 5% of wild type. CO2 assimilation rate was not inhibited until more than 85% of PRK activity had been removed. With reduction in PRK activity between 85% and 95%, assimilation rates were reduced by up to half compared to wild type. It is estimated that changes in amounts of Ru5P, RuBP, ATP, ADP, and 3-PGA would have altered the fine control of PRK in vivo, to realize the assimilation rates observed. Amounts of hexoses and starch, in particular, were reduced in plants expressing the lowest PRK activities; amounts of sucrose were little affected. Transgenic plants expressing sense or antisense PT cDNAs showed a 15-fold range of PT activity, from 20% to 300% of wild-type activity, but there were no consistent differences in photo-synthetic rates between transformants. Starch content was increased by 20% and total soluble sugars decreased by 20% in leaves of antisense transformants compared to sense transformants. The 40% change in the ratio of starch to soluble sugars in these plants indicates that partitioning of assimilate between starch and sugars had been altered. © 1995 Oxford University Press Photosynthetic Carbon Reduction nationallicence Carbon assimilation nationallicence phosphate translocator nationallicence phosphoribulokinase nationallicence starch nationallicence tobacco nationallicence transgenic plant nationallicence Gray John C. Department of Plant Sciences, University of Cambridge Downing Street, Cambridge CB2 3EA, UK aut Paul Matthew J. Biochemistry and Physiology Department, IACR-Rothamsted Harpenden, Herts AL5 2JQ, UK aut Barnes Simon A. Department of Plant Sciences, University of Cambridge Downing Street, Cambridge CB2 3EA, UK aut Knight Jacqueline S. Department of Plant Sciences, University of Cambridge Downing Street, Cambridge CB2 3EA, UK aut Loynes Andrew Department of Plant Sciences, University of Cambridge Downing Street, Cambridge CB2 3EA, UK aut Habash Dimah Biochemistry and Physiology Department, IACR-Rothamsted Harpenden, Herts AL5 2JQ, UK aut Parry Martin A.J. Biochemistry and Physiology Department, IACR-Rothamsted Harpenden, Herts AL5 2JQ, UK aut Lawlor David W. Biochemistry and Physiology Department, IACR-Rothamsted Harpenden, Herts AL5 2JQ, UK aut Journal of Experimental Botany Oxford University Press 46/special_issue(1995-09), 1309-1315 0022-0957 46:special_issue<1309 1995 46 exbotj https://doi.org/10.1093/jxb/46.special_issue.1309 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/jxb/46.special_issue.1309 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Gray John C. Department of Plant Sciences, University of Cambridge Downing Street, Cambridge CB2 3EA, UK aut NATIONALLICENCE 700 1- Paul Matthew J. Biochemistry and Physiology Department, IACR-Rothamsted Harpenden, Herts AL5 2JQ, UK aut NATIONALLICENCE 700 1- Barnes Simon A. Department of Plant Sciences, University of Cambridge Downing Street, Cambridge CB2 3EA, UK aut NATIONALLICENCE 700 1- Knight Jacqueline S. Department of Plant Sciences, University of Cambridge Downing Street, Cambridge CB2 3EA, UK aut NATIONALLICENCE 700 1- Loynes Andrew Department of Plant Sciences, University of Cambridge Downing Street, Cambridge CB2 3EA, UK aut NATIONALLICENCE 700 1- Habash Dimah Biochemistry and Physiology Department, IACR-Rothamsted Harpenden, Herts AL5 2JQ, UK aut NATIONALLICENCE 700 1- Parry Martin A.J. Biochemistry and Physiology Department, IACR-Rothamsted Harpenden, Herts AL5 2JQ, UK aut NATIONALLICENCE 700 1- Lawlor David W. Biochemistry and Physiology Department, IACR-Rothamsted Harpenden, Herts AL5 2JQ, UK aut NATIONALLICENCE 773 0- Journal of Experimental Botany Oxford University Press 46/special_issue(1995-09), 1309-1315 0022-0957 46:special_issue<1309 1995 46 exbotj Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford