Abstract
A dot-blot technique was developed using monoclonal antibodies to measure, rapidly and accurately, the amount of sucrose-phosphate synthase (SPS; EC 2.4.1.14) protein present in a crude extract from spinach (Spinacia oleracea L. cv. Dark Green Bloomsdale) leaves; this was compared with SPS activity in this material. During leaf development, increased SPS activity followed closely the increase in enzyme-protein level, indicating denovo synthesis or altered turn-over rates for SPS. In contrast, activation of SPS by illumination of leaves or by mannose treatment of leaf discs in the dark (M. Stitt et al. Planta 174, 217–230) occurred without a significant change in the level of enzyme protein. Since conditions which altered SPS activity did not affect immunoprecipitation or mobility of the 120-kilodalton (kDa) subunit of the enzyme during denaturing gel electrophoresis, some form of protein modification other than proteolysis must be involved. Overall, the results indicate that regulation of SPS activity can involve changes in the level of enzyme protein and-or covalent modification.
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Abbreviations
- kDa:
-
kilodalton
- SDS-PAGE:
-
sodium dodecylsulfate polyacrylamide gel electrophoresis
- SPS:
-
sucrosephosphate synthase
References
ap Rees, T. (1980) Integration of pathways of synthesis and degradation of hexose phosphates. In: Biochemistry of plants. A comprehensive treatise, vol. 3, pp. 1–41, Preiss, J., ed. Academic Press, New York
Dennis, D.T., Hekman, W.E., Thomson, A., Ireland, R.J., Botha, F.C., Kruger, N.J. 1985. Compartmentation of glycolytic enzymes in plant cells. In: Regulation of carbon partitioning in photosynthetic tissue. pp. 127–146, Heath, R.L., Preiss, J., eds. Waverly Press, Baltimore, Md., USA
Giaquinta, R. (1978) Source and sink leaf metabolism in relation to phloem translocation. Carbon partitioning and enzymology. Plant Physiol. 61, 380–385
Huber, S.C., Ohsugi, R., Usuda, H., Kalt-Torres, W. (1987) Light modulation of maize leaf sucrose phosphate synthase. Plant Physiol. Biochem. 25, 515–523
Huber, S.C., Kerr, P.S., Kalt-Torres, W. (1986) Biochemical control of allocation of carbon for export and storage in source leaves. In: Phloem transport, pp. 355–367, Cronshaw, J., Lucas, W.J., Giaquinta, R.T., eds. Alan R. Liss, New York
Stitt, M., Huber, S.C., Kerr, P.S. (1988a) Control of photosynthetic sucrose formation. In: Biochemistry of plants, vol. 10: Photosynthesis, pp. 328–409, Hatch, M.D., Boardman, N.K., eds. Academic Press, New York
Stitt, M., Wilke, I., Feil, R., Heldt, H.W. (1988b) Coarse control of sucrose phosphate synthase in leaves. Alterations of the kinetic properties in response to the rate of photosynthesis and the accumulation of sucrose. Planta 174, 217–230
Walker, J.L., Huber, S.C. (1988a) Production and preliminary characterization of monoclonal antibodies spinach leaf sucrose phosphate synthase. Plant Physiol. in press
Wlaker, J.L., Huber, S.C. (1988b) Evidence for covalent modification of spinach leaf sucrose-phosphate synthase. (Abstr.) Plant Physiol. 86, Suppl., 6
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Cooperative investigations of the U.S. Department of Agriculture, Agricultural Research Service, and the North Carolina Agricultural Reseach Service, Raleigh. Paper No. 11789 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, NC 27695-7643, USA
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Walker, J.L., Huber, S.C. Regulation of sucrose-phosphate-synthase activity in spinach leaves by protein level and covalent modification. Planta 177, 116–120 (1989). https://doi.org/10.1007/BF00392161
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DOI: https://doi.org/10.1007/BF00392161