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Accumulation of the β-subunit of polygalacturonase 1 in normal and mutant tomato fruit

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Polyclonal antiserum raised against the native PG1 isoform of tomato fruit (Lycopersicon esculentum Mill.) polygalacturonase [poly(1,4-α-d-galacturonide) glycanohydrolase, EC] bound to each of the subunits of the protein and also to a range of other fruit proteins. Affinity purification was used to remove antibody molecules that bound to the native form of the PG2 isoform. The resulting serum bound to native PG1, denatured PG2 and β-subunits of PG1 but not to native PG2 or other fruit proteins. This anti-PG1 serum was used to monitor the occurrence of the PG1 β-subunit and PG2 in detergent extracts of tomato tissues. The β-subunit polypeptide was detected in pericarp but not locule tissue of fruit, including fruit of the rin and nor mutants. It increased in amount in the pericarp tissues from an early stage to the mature green stage, clearly prior to any appreciable accumulation of the PG2 subunit. The β-subunit polypeptide was not detected in stem or leaf tissues. A PG2-specific antiserum was used to study the interaction of PG2 with the isolated β-subunit. The PG2 isoform was bound to the β-subunit over a wide range of salt concentrations and pH; the interaction was independent of the presence of reducing agents. It is concluded that strong non-covalent forces are involved in the interaction. The results are consistent with a model in which the β-subunit is positioned in the cell wall structure and provides a specific binding site for the active PG2 subunit when this is synthesised during ripening.

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mature green

Mr :

relative molecular mass

nor :

non-ripening mutant


polyacrylamide gel electrophoresis



rin :

ripening inhibitor mutant


sodium dodecyl sulphate


  1. Ali, Z.M., Brady, C.J. (1982) Purification and characterization of the polygalacturonases of tomato fruits. Aust. J. Plant Physiol. 9, 155–169

  2. Baron-Epel, O., Gharyal, P.K., Schindler, M. (1988) Pectins as mediators of wall porosity in soybean cells. Planta 175, 389–395

  3. Brady, C.J., McGlasson, W.B., Pearson, J.A., Meldrum, S.K., Kopeliovitch, E. (1985) Interactions between the amount and molecular forms of polygalacturonase, calcium and firmness in tomato fruit. J. Am. Soc. Hort. Sci. 110, 254–258

  4. Brady, C.J., McGlasson, W.B., Speirs, J. (1987) The biochemistry of fruit ripening. In: Tomato biotechnology, pp. 279–288, Nevins, D.J., Jones, R.A., eds. Alan R. Liss, New York

  5. Buescher, R.W., Sistrunk, W.A., Tigchelaar, E.G., Ng, T.J. (1976) Softening, pectolytic activity, and storage-life of rin and nor tomato hybrids. HortScience 11, 603–604

  6. Carpita, N., Sabularse, D., Montezinos, D., Delmer, D.P. (1979) Determination of the pore size of cell walls of living plant cells. Science 205, 1144–1147

  7. DellaPenna, D., Bennett, A.B. (1988). In vitro synthesis and processing of tomato fruit polygalacturonase. Plant Physiol. 86, 1057–1063

  8. DellaPenna, D., Alexander, D.C., Bennett, A.B. (1986) Molecular cloning of tomato fruit polygalacturonase: Analysis of polygalacturonase mRNA levels during ripening. Proc. Natl. Acad. Sci. USA 83, 6420–6424

  9. DellaPenna, D., Lashbrook, C.C., Toenjes, K., Giovannoni, J.J., Fischer, R.L., Bennett, A.B. (1990) Polygalacturonase isozymes and pectin depolymerization in transgenic rin tomato fruit. Plant Physiol. 94, 1882–1886

  10. Fischer, R.L., Bennett, A.B. (1991) Role of cell wall hydrolases in fruit ripening. Annu. Rev. Plant Physiol. 42, 675–703

  11. Giovannoni, J.J., DellaPenna, D., Bennett, A.B., Fischer, R.L. (1989) Expression of a chimeric polygalacturonase gene in transgenic rin (ripening inhibitor) tomato fruit results in polyuronide degradation but not fruit softening. Plant Cell 1, 53–63

  12. Goding, J.W. (1986) Monoclonal antibodies: principles and practice. Academic Press, Sydney

  13. Grierson, D., Tucker, G.A., Keen, J., Ray, J., Bird, C.R., Schuch, W. (1986) Sequencing and identification of a cDNA clone for tomato polygalacturonase. Nucleic Acids Res. 14, 8595–8603

  14. Harriman, R.W., Tieman, D.M., Handa, A.K. (1991) Molecular cloning of tomato pectin methylesterase gene and its expression in Rutgers, Ripening Inhibitor, Nonripening, and Never Ripe tomato fruits. Plant Physiol. 97, 80–87

  15. Jurd, R.D. (1981) Immunoelectrophoresis. In: Gel electrophoresis of proteins: a practical approach, pp. 229–248, Hames, B.D., Rickwood, D., eds. IRL Press, London

  16. Knegt, E., Vermeer, E., Bruinsma, J. (1988) Conversion of the polygalacturonase isoenzymes from ripening tomato fruits. Physiol. Plant. 72, 108–114

  17. Knegt, E., Vermeer, E., Pak, C., Bruinsma, J. (1991) Function of the polygalacturonase convertor in ripening tomato fruit. Physiol. Plant. 82, 237–242

  18. Kramer, M., Sanders, R.A., Sheehy, R.E., Melis, M., Kuehn, M., Hiatt, W.R. (1990) Field evaluation of tomatoes with reduced polygalacturonase by antisense RNA. In: Plant biology, pp.347–356, Bennett, A.B., O'Neill, S.D., eds. Wiley-Liss, New York

  19. Labavitch, J.M. (1981) Cell wall turnover in plant development. Annu. Rev. Plant Physiol. 32, 385–406

  20. Laue, T.M., Rhodes, D.G. (1990) Determination of size, molecular weight and presence of subunits. In: Methods in enzymology, pp. 566–587, Deutscher, M. P., ed. Academic Press, Sydney

  21. Lauriere, M., Lauriere, C., Chrispeels, M.J., Johnson, K.D., Starm, A. (1989) Characterization of a xylose-specific antiserum that reacts with the complex asparagine-linked glycans of extracellular and vacuolar glycoproteins. Plant Physiol. 90, 1182–1188

  22. McGlasson, W.B., Wade, N.L., Adato, I. (1978) Phytohormones and fruit ripening. In: Phytohormones and related compounds — A comprehensive treatise, pp. 447–493, Letham, D.S., Goodwin, P.B., Higgins, T.J.V., eds. Elsevier, Amsterdam

  23. McManus, M.T., McKeating, J., Sechers, D.S., Osborne, D.J., Ashford, D., Dwek, R.A., Rademacher, T.W. (1988) Identification of a monoclonal antibody to abscission tissue that recognises xylose/fucose-containing N-linked oligosaccharides from higher plants. Planta 175, 506–512

  24. Moshrefi, M., Luh, B.S. (1983) Carbohydrate composition and electrophoretic properties of tomato polygalacturonase isoenzymes. Eur. J. Biochem. 135, 511–514

  25. Ng, T.J., Tigchelaar, E.C. (1977) Action of the non-ripening (nor) mutant on fruit ripening of tomato. J. Am. Soc. Hort. Sci. 102, 504–509

  26. Osteryoung, K.W., Toenjes, K., Hall, B., Winkler, V., Bennett, A.B. (1990) Analysis of tomato polygalacturonase expression in transgenic tobacco. Plant Cell 2, 1239–1248

  27. Pogson, B.J., Brady, C.J. (1993) Do multiple forms of tomato fruit endopolygalacturonase exist in situ? Postharvest Biol. Technol., in press

  28. Pogson, B.J., Brady, C.J., Orr, G.R. (1991) On the occurrence and structure of subunits of endopolygalacturonase isoforms in mature-green and ripening tomato fruits. Aust. J. Plant Physiol. 18, 65–79

  29. Pogson, B.J., Seymour, G.B., Brady, C.J., Jones, M., Goodchild, D. (1992) Immunolocalisation of pectinases in tomato fruit. NZ J. Crop Hort. Sci. 20, 137–146

  30. Pressey, R. (1984) Purification and characterization of tomato polygalacturonase converter. Eur. J. Biochem. 144, 217–220

  31. Pressey, R. (1986a) Changes in polygalacturonase isoenzymes and converter in tomatoes during ripening. J. Hort. Sci. 21, 1183–1185

  32. Pressey, R. (1986b) Extraction and assay of tomato polygalacturonase. HortScience 21, 490–492

  33. Pressey, R. (1988) Reevaluation of the changes in polygalacturonases in tomatoes during ripening. Planta 174, 39–43

  34. Pressey, R., Avants, J.K. (1973) Two forms of polygalacturonase in tomatoes. Biochim. Biophys. Acta 309, 363–369

  35. Ray, J., Knapp, J., Grierson, D., Bird, C., Schuch, W. (1988) Identification and sequence determination of a cDNA clone for tomato pectin esterase. Eur. J. Biochem. 174, 119–124

  36. Reisfeld, R.A., Lewis, U.J., Williams, D.E. (1962) Disc electrophoresis of basic proteins and peptides on polyacrylamide gels. Nature 195, 281–283

  37. Sheehy, R.E., Pearson, J., Brady, C.J., Hiatt, W.R. (1987) Molecular characterization of tomato fruit polygalacturonase. Mol. Gen. Genet. 208, 30–36

  38. Smith, C.J.S., Watson, C.F., Morris, P.C., Bird, C.R., Seymour, G.B., Gray, J.E., Arnold, C., Tucker, G.A., Schuch, W., Harding, S., Grierson, D. (1990) Inheritance and effect on ripening of antisense polygalacturonase genes in transgenic tomatoes. Plant Mol. Biol. 14, 369–379

  39. Speirs, J., Brady, C.J. (1981) A coordinated decline in the synthesis of subunits of ribulose bisphosphate carboxylase in aging wheat leaves. II Abundance of messenger RNA. Aust. J. Plant Physiol. 8, 603–618

  40. Taiz, L. (1984) Plant cell expansion: Regulation of cell wall mechanical properties. Annu. Rev. Plant Physiol. 35, 585–657

  41. Tigchelaar, E.C., McGlasson, W.B., Buescher, R.W. (1978) Genetic regulation of tomato fruit ripening. HortScience 13, 508–513

  42. Tucker, G.A., Robertson, N.G., Grierson, D. (1980) Changes in polygalacturonase isoenzymes during the ‘ripening’ of normal and mutant tomato fruit. Eur. J. Biochem. 112, 119–124

  43. Tucker, G.A., Robertson, N.G., Grierson, D. (1981) The conversion of tomato-fruit polygalacturonase isoenzyme 2 into isoenzyme 1 in vitro. Eur. J. Biochem. 115, 87–90

  44. Zheng, L., Heupel, R.C., DellaPenna, D. (1992) The b subunit of tomato fruit polygalacturonase isoenzyme 1: Isolation, characterization, and identification of unique structural features. Plant Cell 4, 1147–1156

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Correspondence to Colin J. Brady.

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Pogson, B.J., Brady, C.J. Accumulation of the β-subunit of polygalacturonase 1 in normal and mutant tomato fruit. Planta 191, 71–78 (1993). https://doi.org/10.1007/BF00240897

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Key words

  • Fruit ripening
  • Lycopersicon (fruit ripening)
  • Mutant (tomato)
  • Polygalacturonase (β-subunit)