Modulation of amino acid metabolism in transformed tobacco plants deficient in Fd-GOGAT

被引:47
作者
Ferrario-Méry, S
Suzuki, A
Kunz, C
Valadier, MH
Roux, Y
Hirel, B
Foyer, CH
机构
[1] INRA, Lab Metab & Nutr Plantes, F-78026 Versailles, France
[2] AFRC, Inst Arable Crops Res, Dept Biochem & Physiol, Harpenden AL5 2JQ, Herts, England
关键词
alpha-ketoglutarate; amino acid; ammonium assimilation; glutamate synthase; Nicotiana tabacum; transgenic plant;
D O I
10.1023/A:1004715208478
中图分类号
S3 [农学(农艺学)];
学科分类号
0901 ;
摘要
Tobacco (Nicotiana tabacum) plants expressing a partial ferredoxin-dependent glutamine-2-oxoglutarate aminotransferase (Fd-GOGAT) cDNA in the antisense orientation under the control of the 35S promoter, were used to study the metabolism of amino acids, 2-oxoglutarate and ammonium following the transition from CO2 enrichment (where photorespiration is inhibited) to air (where photorespiration is a major process of ammonium production in leaves). The leaves of the lowest Fd-GOGAT expressors accumulated more foliar glutamine (Gln) and alpha-ketoglutarate (alpha-KG) than the untransformed controls in both growth conditions. Photorespiration-dependent increases in foliar ammonium, glutamine, alpha-KG and total amino acids were proportional to the decreases in foliar Fd-GOGAT activity. No change in endoprotease activity was observed following transfer to air in the Fd-GOGAT transformants or the untransformed controls which has similar activities over a broad range of pH values. We conclude that several pathways of amino acid biosynthesis are modified when NH4+ and Gln accumulate in leaves.
引用
收藏
页码:67 / 79
页数:13
相关论文
共 37 条