Abstract
In some soybean (Glycine max (L.) Merr.) cultivars, fruit removal does not delay the apparent loss of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco, EC 4.1.1.39) activity and abundance or the decline in photosynthesis. Analysis of leaf extracts from defruited plants indicated a time-dependent increase in both Rubisco activity and abundance in a 30000 · g pellet fraction in cultivars which had been reported to lose all Rubisco protein from the supernatant fraction. Attempts to solubilize the pelleted Rubisco by increasing the buffer volume/tissue ratio or by adding alkylphenoxypolyethoxyethanol (Triton X-100), ethylenediaminetetraacetic acid (EDTA), or NaCl were unsuccessful. However, treatment of the pellets with denaturants such as 8 M urea or 5% (w/v) sodium dodecyl sulfate (SDS) did release Rubisco from the pellet. Redistribution of protein to the pellet fraction appeared to be specific for Rubisco since the amount of ribulose-5-phosphate kinase (EC 2.7.1.19) found in the pellet fraction of leaf extracts of control and defruited plants was small and constant over time. The loss of soluble Rubisco, and the concomitant increase in insoluble Rubisco, in response to fruit removal varied with genotype and was reproducible in both field and greenhouse environments. In addition, the effect was influenced by node position and light; lower and-or shaded leaves exhibited less Rubisco in the pellet fraction than leaves from the top of the plant that was fully exposed to sunlight. When isolated by sucrose-density-gradient centrifugation, the insoluble Rubisco was found to co-purify with a 30-kDa (kilodalton) polypeptide. These results indicate that alteration of the source/sink ratio by removing fruits results in the formation of an insoluble form of Rubisco in leaf extracts of soybean. Whether or not Rubisco exists as an insoluble complex with the 30-kDa polypeptide in intact leaves of defruited plants remains to be determined.
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Abbreviations
- kDa:
-
kilodalton
- PGA kinase:
-
3-phosphoglyceric acid kinase (EC 2.7.2.3)
- Rubisco:
-
ribulose-1,5-bisphosphate car-boxylase/oxygenase (EC 4.1.1.39)
- Ru5P kinase:
-
ribulose-5-phosphate kinase (EC 2.7.1.19)
- SDS-PAGE:
-
sodium dodecyl sulfatepolyacrylamide gel electrophoresis
References
Chua, N.-H. (1980) Electrophoretic analysis of chloroplast proteins. Methods Enzymol. 69, 434–446
Crafts-Brandner, S.J., Egli, D.B. (1987a) Sink removal and leaf senescence in soybean. Cultivar effects. Plant Physiol. 85, 662–666
Crafts-Brandner, S.J., Egli, D.B. (1987b) Modification of seed growth by physical restraint: effect on leaf senescence. J. Exp. Bot. 38, 2043–2049
Crafts-Brandner, S.J., Below, F.E., Harper, J.E., Hageman, R.H. (1984) Effects of pod removal on metabolism and senescence of nodulating and nonnodulating soybean isolines. Enzymes and chlorophyll. Plant Physiol. 75, 318–322
Crafts-Brandner, S.J., Salvucci, M.E., Egli, D.B. (1990) Changes in ribulosebisphosphate carboxylase/oxygenase and ribulose 5 phosphate kinase abundances and photosynthetic capacity during leaf senescence. Photosynth. Res. 23, 223–230
Fehr, W.R., Caviness, C.E. (1977) Stages of soybean development. Spec. Rep. No. 80, Cooperative Extension Service, Agricultural and Home Economics Experiment Station, Iowa State University, Ames, USA
Heitholt, J.J., Egli, D.B. (1985) Influence of deflowering on dry matter production of soybeans. Field Crops Res. 12, 163–173
Huber, S.C. Wilson, R.F., Burton, J.W. (1983) Studies on genetic male-sterile soybeans. II. Effect of nodulation on photosynthesis and carbon partitioning in leaves. Plant Physiol. 73, 713–717
Makino, A., Mae, T., Ohira, K. (1983) Photosynthesis and ribulose 1,5-bisphosphate carboxylase in rice leaves. Changes in photosynthesis and enzymes involved in carbon assimilation from leaf development through senescence. Plant Physiol. 73, 1002–1007
McNeil, P.H., Walker, D.A. (1981) The effect of magnesium and other ions on the distribution of ribulose 1,5-bisphosphate carboxylase in chloroplast extracts. Arch. Biochem. Biophys. 208, 184–188
Mondal, M.H., Brun, W.A., Brenner, M.L. (1978) Effects of sink removal on photosynthesis and senescence in leaves of soybean (Glycine max L. Merr.) plants. Plant Physiol. 61, 394–397
Salvucci, M.E., Anderson, J.C. (1987) Factors affecting the activation state and the level of total activity of ribulose bisphosphate carboxylase in tobacco protoplasts. Plant Physiol. 85, 66–71
Salvucci, M.E., Ogren, W.L. (1985) A Chlamydomonas reinhardii mutant with catalytically and structurally altered ribulose-5phosphate kinase. Planta 165, 340–347
Schweitzer, L.E., Harper, J.E. (1985) Leaf nitrate reductase, Dribulose-1,5-bisphosphate carboxylase, and root nodule development of genetic male-sterile and fertile soybean isolines. Plant Physiol. 78, 61–65
Wittenbach, V.A. (1982) Effect of pod removal on leaf senescence in soybeans. Plant Physiol. 70, 1544–1548
Wittenbach, V.A. (1983 a) Effect of pod removal on leaf photosynthesis and soluble protein composition of field-grown soybeans. Plant Physiol. 73, 121–124
Wittenbach, V.A. (1983b) Purification and characterization of a soybean leaf storage glycoprotein. Plant Physiol. 73, 125–129
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Crafts-Brandner, S.J., Salvucci, M.E. & Egli, D.B. Fruit removal in soybean induces the formation of an insoluble form of ribulose-1,5-bisphosphate carboxylase/oxygenase in leaf extracts*. Planta 183, 300–306 (1991). https://doi.org/10.1007/BF00197802
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DOI: https://doi.org/10.1007/BF00197802