caa a22 4500 477100368 CHVBK 20180405111539.0 cr unu---uuuuu 170330e19961001xx s 000 0 eng 10.1007/BF00208311 doi (NATIONALLICENCE)springer-10.1007/BF00208311 Regulation of the subunit composition of tomato plastidic glutamine synthetase by light and the nitrogen source [Elektronische Daten] [Andrea Migge, Gudrun Meya, Elisa Carrayol, Bertrand Hirel, Thomas Becker] The co-action of light and the N-source in the regulation of the expression of the single-copy gene encoding plastidic glutamine synthetase (GS-2) and of the multigene family encoding cytosolic glutamine synthetase (GS-1) was investigated in the cotyledons of tomato (Lycopersicon esculentum L.). Light, acting at red/far red or at blue regions of the spectrum increased the abundance of the GS-2 gene product and induced a modification of GS-2 subunits, resulting in the appearance of two GS-2 proteins exhibiting different molecular weights. The magnitude of the light stimulation of GS-2 gene expression was independent of the nitrogen source. However, following red- or far-red-light treatment of etiolated tomato cotyledons, two GS-2 proteins were found when nitrate was the N-source, while only one GS-2 protein was present with ammonium as the sole nitrogen source. Thus, light of specific wavelengths and N-substrates seem to act in concert to regulate GS-2 subunit composition. Tomato GS-1 gene expression was unaffected by light. Ammonium provided externally increased the level of the tomato GS-1 protein. Irrespective of the N-source or the light quality, the GS-1 subunits were represented by polypeptides of similar molecular weight in tomato cotyledons. However, phosphinothricin-induced inhibition of GS activity resulted in the appearance of at least one additional GS-1 polypeptide in etiolated or in green tomato cotyledons. In addition, impairment of GS activity in green tomato cotyledons by phosphinothricin was correlated with an increased level of the GS-1 transcript. Taken together, our data suggest a metabolic control of GS-1 gene expression in green tomato cotyledons. Springer-Verlag, 1996 Gene expression nationallicence Glutamine synthetase nationallicence Nitrogen source nationallicence Phosphinothricin nationallicence Phytochrome nationallicence Solanum nationallicence GS : glutamine synthetase nationallicence GS-1 : cytosolic GS nationallicence GS-2 : plastidic GS nationallicence Pt : phosphinothricin nationallicence Migge Andrea Lehrstuhl für Genetik, Universität Bielefeld, P.O. Box 100131, D-33501, Bielefeld, Germany aut Meya Gudrun Lehrstuhl für Stoffwechselphysiologie, Universität Bielefeld, Germany aut Carrayol Elisa Laboratoire du Métabolisme et de la Nutrition des Plantes, INRA, Centre de Versailles, Route de Saint-Cyr, F-78026, Versailles Cedex, France aut Hirel Bertrand Laboratoire du Métabolisme et de la Nutrition des Plantes, INRA, Centre de Versailles, Route de Saint-Cyr, F-78026, Versailles Cedex, France aut Becker Thomas Lehrstuhl für Genetik, Universität Bielefeld, P.O. Box 100131, D-33501, Bielefeld, Germany aut Planta Springer-Verlag 200/2(1996-10-01), 213-220 0032-0935 200:2<213 1996 200 425 https://doi.org/10.1007/BF00208311 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00208311 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Migge Andrea Lehrstuhl für Genetik, Universität Bielefeld, P.O. Box 100131, D-33501, Bielefeld, Germany aut NATIONALLICENCE 700 1- Meya Gudrun Lehrstuhl für Stoffwechselphysiologie, Universität Bielefeld, Germany aut NATIONALLICENCE 700 1- Carrayol Elisa Laboratoire du Métabolisme et de la Nutrition des Plantes, INRA, Centre de Versailles, Route de Saint-Cyr, F-78026, Versailles Cedex, France aut NATIONALLICENCE 700 1- Hirel Bertrand Laboratoire du Métabolisme et de la Nutrition des Plantes, INRA, Centre de Versailles, Route de Saint-Cyr, F-78026, Versailles Cedex, France aut NATIONALLICENCE 700 1- Becker Thomas Lehrstuhl für Genetik, Universität Bielefeld, P.O. Box 100131, D-33501, Bielefeld, Germany aut NATIONALLICENCE 773 0- Planta Springer-Verlag 200/2(1996-10-01), 213-220 0032-0935 200:2<213 1996 200 425 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer