caa a22 4500 467901546 CHVBK 20180406152819.0 cr unu---uuuuu 170328e20061101xx s 000 0 eng 10.1007/s00299-006-0181-y doi (NATIONALLICENCE)springer-10.1007/s00299-006-0181-y Expression of ipt gene controlled by an ethylene and auxin responsive fragment of the LEACO1 promoter increases flower number in transgenic Nicotiana tabacum [Elektronische Daten] [Mariya Khodakovskaya, Degang Zhao, William Smith, Yi Li, Richard McAvoy] Cytokinins play important roles in regulating plant growth and development. A new genetic construct for regulating cytokinin content in plant cells was cloned and tested. The gene coding for isopentenyl transferase (ipt) was placed under the control of a 0.821kb fragment of the 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase gene promoter from Lycopersicon esculentum (LEACO1) and introduced into Nicotiana tabacum (cv. Havana). Some LEACO10.821kb-ipt transgenic plant lines displayed normal shoot morphology but with a dramatic increase in the number of flower buds compared to nontransgenic plants. Other transgenic lines produced excessive lateral branch development but no change in flower bud number. Isolated leaves of transgenic tobacco plants showed a significantly prolonged retention of chlorophyll under dark incubation (25°C for 20 days). Leaves of nontransformed plants senesced gradually under the same conditions. Experiments with LEACO10.821kb-gus transgenic tobacco plants suggested auxin and ethylene involvement in induction of LEACO10.821kb promoter activity. Multiple copies of nucleotide base sequences associated with either ethylene or auxin response elements were identified in the LEACO10.821kb promoter fragment. The LEACO10.821kb-ipt fusion gene appears to have potential utility for improving certain ornamental and agricultural crop species by increasing flower bud initiation and altering branching habit. Springer-Verlag, 2006 Transgenic Nicotiana tabacum nationallicence Fragment of LEACO1 promoter nationallicence IPT expression nationallicence Leaf senescence nationallicence Number of flower buds nationallicence Khodakovskaya Mariya Plant Science Department, University of Connecticut, 06269-4163, Storrs, CT, USA aut Zhao Degang Plant Science Department, University of Connecticut, 06269-4163, Storrs, CT, USA aut Smith William Plant Science Department, University of Connecticut, 06269-4163, Storrs, CT, USA aut Li Yi Plant Science Department, University of Connecticut, 06269-4163, Storrs, CT, USA aut McAvoy Richard Plant Science Department, University of Connecticut, 06269-4163, Storrs, CT, USA aut Plant Cell Reports Springer-Verlag 25/11(2006-11-01), 1181-1192 0721-7714 25:11<1181 2006 25 299 https://doi.org/10.1007/s00299-006-0181-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00299-006-0181-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Khodakovskaya Mariya Plant Science Department, University of Connecticut, 06269-4163, Storrs, CT, USA aut NATIONALLICENCE 700 1- Zhao Degang Plant Science Department, University of Connecticut, 06269-4163, Storrs, CT, USA aut NATIONALLICENCE 700 1- Smith William Plant Science Department, University of Connecticut, 06269-4163, Storrs, CT, USA aut NATIONALLICENCE 700 1- Li Yi Plant Science Department, University of Connecticut, 06269-4163, Storrs, CT, USA aut NATIONALLICENCE 700 1- McAvoy Richard Plant Science Department, University of Connecticut, 06269-4163, Storrs, CT, USA aut NATIONALLICENCE 773 0- Plant Cell Reports Springer-Verlag 25/11(2006-11-01), 1181-1192 0721-7714 25:11<1181 2006 25 299 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer