Trehalose 6-phosphate regulates starch synthesis via posttranslational redox activation of ADP-glucose pyrophosphorylase

Proceedings of the National Academy of Sciences of the United States of America - Tập 102 Số 31 - Trang 11118-11123 - 2005
Anna Kolbe1, Axel Tiessen1, Henriette Schluepmann1, Matthew J. Paul1, Silke Ulrich1, Peter Geigenberger1
1Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Golm, Germany; Department of Molecular Plant Physiology, Utrecht University, Padualaan 8, 3584CH Utrecht, The Netherlands; and Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, United Kingdom

Tóm tắt

Trehalose is the most widespread disaccharide in nature, occurring in bacteria, fungi, insects, and plants. Its precursor, trehalose 6-phosphate (T6P), is also indispensable for the regulation of sugar utilization and growth, but the sites of action are largely unresolved. Here we use genetic and biochemical approaches to investigate whether T6P acts to regulate starch synthesis in plastids of higher plants. Feeding of trehalose to Arabidopsis leaves led to stimulation of starch synthesis within 30 min, accompanied by activation of ADP-glucose pyrophosphorylase (AGPase) via posttranslational redox modification. The response resembled sucrose but not glucose feeding and depended on the expression of SNF1-related kinase. We also analyzed transgenic Arabidopsis plants with T6P levels increased by expression of T6P synthase or decreased by expression of T6P phosphatase (TPP) in the cytosol. Compared with wild type, leaves of T6P synthase-expressing plants had increased redox activation of AGPase and increased starch, whereas TPP-expressing plants showed the opposite. Moreover, TPP expression prevented the increase in AGPase activation in response to sucrose or trehalose feeding. Incubation of intact isolated chloroplasts with 100 μM T6P significantly and specifically increased reductive activation of AGPase within 15 min. Results provide evidence that T6P is synthesized in the cytosol and acts on plastidial metabolism by promoting thioredoxin-mediated redox transfer to AGPase in response to cytosolic sugar levels, thereby allowing starch synthesis to be regulated independently of light. The discovery informs about the evolution of plant metabolism and how chloroplasts of prokaryotic origin use an intermediate of the ancient trehalose pathway to report the metabolic status of the cytosol.

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Tài liệu tham khảo

Martin, C. & Smith, A. M. (1995) Plant Cell 7, 971-985.7640529

Geigenberger P. & Fernie A. R. (2005) in Food Biochemistry and Food Processing ed. Hui Y. H. (Blackwell Ames IA) in press.

10.1104/pp.85.1.182

10.1104/pp.93.2.785

10.1007/BF02411398

10.1111/j.1365-3040.2004.01183.x

Preiss, J. (1988) in The Biochemistry of Plants, ed. Preiss, J. (Academic, San Diego), Vol. 14, pp. 181-254.

10.1074/jbc.273.39.25045

10.1074/jbc.275.2.1315

10.1093/jxb/eri178

10.1105/tpc.003640

10.1104/pp.103.024513

10.1146/annurev.pp.31.060180.002013

10.1104/pp.96.1.1

10.1146/annurev.arplant.56.032604.144246

10.1046/j.1365-313X.2003.01823.x

Smeekens, S. (2000) Plant Mol. Biol. 51, 49-81.

10.1016/S0968-0004(00)88938-0

10.1016/S1369-5266(03)00037-2

10.1016/S1567-1356(03)00222-8

10.1046/j.1365-313x.2002.01220.x

10.1073/pnas.1132018100

10.1104/pp.104.039503

10.1046/j.1365-313X.1998.00108.x

10.1007/BF00310888

10.1016/0014-5793(93)80191-V

10.1007/BF00313424

10.1111/j.1574-6968.1994.tb07102.x

10.1042/bj3530157

10.1146/annurev.arplant.51.1.371

10.1111/j.1365-313X.2003.02012.x

10.1126/science.1091811

10.1111/j.1365-313X.2004.02016.x

10.1093/jxb/erg038

10.1073/pnas.94.20.11096

10.1016/S0168-9452(99)00163-6

10.1074/jbc.M401280200

10.1074/jbc.M400549200

10.1194/jlr.M400341-JLR200

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Proceedings of the National Academy of Sciences of the United States of America

Tập 102 Số 31

11118-11123

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