caa a22 4500 606208682 CHVBK 20210128101024.0 cr unu---uuuuu 210128e20150101xx s 000 0 eng 10.1007/s00425-014-2165-4 doi (NATIONALLICENCE)springer-10.1007/s00425-014-2165-4 Impact of concurrent overexpression of cytosolic glutamine synthetase (GS1) and sucrose phosphate synthase (SPS) on growth and development in transgenic tobacco [Elektronische Daten] [Mark Seger, Sayed Gebril, Jules Tabilona, Amanda Peel, Champa Sengupta-Gopalan] Main conclusion : The outcome of simultaneously increasing SPS and GS activities in transgenic tobacco, suggests that sucrose is the major determinant of growth and development, and is not affected by changes in N assimilation. Abstract: Carbon (C) and nitrogen (N) are the major components required for plant growth and the metabolic pathways for C and N assimilation are very closely interlinked. Maintaining an appropriate balance or ratio of sugar to nitrogen metabolites in the cell, is important for the regulation of plant growth and development. To understand how C and N metabolism interact, we manipulated the expression of key genes in C and N metabolism individually and concurrently and checked for the repercussions. Transgenic tobacco plants with a cytosolic soybean glutamine synthetase (GS1) gene and a sucrose phosphate synthase (SPS) gene from maize, both driven by the CaMV 35S promoter were produced. Co-transformants, with both the transgenes were produced by sexual crosses. While GS is the key enzyme in N assimilation, involved in the synthesis of glutamine, SPS plays a key role in C metabolism by catalyzing the synthesis of sucrose. Moreover, to check if nitrate has any role in this interaction, the plants were grown under both low and high nitrogen. The SPS enzyme activity in the SPS and SPS/GS1 co-transformants were the same under both nitrogen regimens. However, the GS activity was lower in the co-transformants compared to the GS1 transformants, specifically under low nitrogen conditions. The GS1/SPS transformants showed a phenotype similar to the SPS transformants, suggesting that sucrose is the major determinant of growth and development in tobacco, and its effect is only marginally affected by increased N assimilation. Sucrose may be functioning in a metabolic capacity or as a signaling molecule. Springer-Verlag Berlin Heidelberg, 2014 Sucrose phosphate synthase (SPS) nationallicence Cytosolic glutamine synthetase (GS1) nationallicence Co-transformants nationallicence C:N ratio nationallicence Sucrose:starch ratio nationallicence SPS : Sucrose phosphate synthase nationallicence GS1 : Cytosolic glutamine synthetase nationallicence Suc : Sucrose nationallicence Glc : Glucose nationallicence Gln : Glutamine nationallicence HN : High nitrogen nationallicence LN : Low nitrogen nationallicence C : Carbon nationallicence N : Nitrogen nationallicence NT : Non transformed nationallicence MzSPS : Maize SPS gene nationallicence Gmgln150 : Soybean GS1 gene without 3′UTR nationallicence GS1/SPS : Co-transformant with both GS 1 and SPS genes nationallicence Seger Mark Department of Plant and Environmental Sciences, New Mexico State University, 88003, Las Cruces, NM, USA aut Gebril Sayed Department of Plant and Environmental Sciences, New Mexico State University, 88003, Las Cruces, NM, USA aut Tabilona Jules Department of Plant and Environmental Sciences, New Mexico State University, 88003, Las Cruces, NM, USA aut Peel Amanda Department of Plant and Environmental Sciences, New Mexico State University, 88003, Las Cruces, NM, USA aut Sengupta-Gopalan Champa Department of Plant and Environmental Sciences, New Mexico State University, 88003, Las Cruces, NM, USA aut Planta Springer Berlin Heidelberg 241/1(2015-01-01), 69-81 0032-0935 241:1<69 2015 241 425 https://doi.org/10.1007/s00425-014-2165-4 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00425-014-2165-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Seger Mark Department of Plant and Environmental Sciences, New Mexico State University, 88003, Las Cruces, NM, USA aut NATIONALLICENCE 700 1- Gebril Sayed Department of Plant and Environmental Sciences, New Mexico State University, 88003, Las Cruces, NM, USA aut NATIONALLICENCE 700 1- Tabilona Jules Department of Plant and Environmental Sciences, New Mexico State University, 88003, Las Cruces, NM, USA aut NATIONALLICENCE 700 1- Peel Amanda Department of Plant and Environmental Sciences, New Mexico State University, 88003, Las Cruces, NM, USA aut NATIONALLICENCE 700 1- Sengupta-Gopalan Champa Department of Plant and Environmental Sciences, New Mexico State University, 88003, Las Cruces, NM, USA aut NATIONALLICENCE 773 0- Planta Springer Berlin Heidelberg 241/1(2015-01-01), 69-81 0032-0935 241:1<69 2015 241 425