, Volume 130, Issue 2, pp 189–196 | Cite as

An enzyme to degrade lettuce endosperm cell walls. Appearance of a mannanase following phytochrome- and gibberellin-induced germination

  • P. Halmer
  • J. D. Bewley
  • T. A. Thorpe


Lettuce seeds (Lactuca sativa L. cv. Grand Rapids) stimulated to germinate by gibberellin and red light produce large amounts of endo-β-mannanase. This enzyme increases markedly following radicle emergence and is capable of degrading mannose-containing polysaccharides, which are the major components of the endosperm cell wall. Non-germinated seeds contain little enzyme and under conditions where gibberellin- or red light-stimulated germination is prevented (eg. by abscisic acid or prolonged far red light) enzyme levels remain low. Cycloheximide inhibits the increase in enzyme levels when supplied to germinating seeds, but the enzyme once produced is stable in vivo in the presence of this inhibitor for at least 24h. The majority of the extractable mannanase activity is located in the endosperm and we propose that the function of this enzyme is to mobilise the endosperm cell wall polysaccharides as a nutrient source for the growing embryo.



abscisic acid




gibberellic acid


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Andrews, P., Hough, L., Jones, J.K.N.: Mannose containing polysaccharides. Part II. The galactomannan of fenugreek seed (Trigonella foenum-graecum). J. Chem. Soc. 2744–2750 (1952)Google Scholar
  2. Andrews, P., Hough, L., Jones, J.K.N.: Mannose containing polysaccharides. Part III. The polysaccharides in the seeds of Iris ochroleuca and I. sibirica. J. Chem. Soc. 1186–1192 (1953)Google Scholar
  3. Bewley, J.D., Black, M.: Protein synthesis during gibberellin induced germination of lettuce seed. Canad. J. Bot. 50, 53–59 (1972)Google Scholar
  4. Bewley, J.D., Fountain, D.W.: A distinction between the actions of abscisic acid, gibberellic acid and cytokinins in light sensitive lettuce seed. Planta (Berl.) 102, 368–371 (1972)Google Scholar
  5. Bewley, J.D., Negbi, M., Black, M.: Immediate phytochrome action in lettuce seeds and its interaction with gibberellins and other germination promoters. Planta (Berl.) 78, 351–357 (1968)Google Scholar
  6. Black, M.: Light controlled germination of seeds. In: Symp. Soc. exp. Biol. 23, 193–218 (1969)Google Scholar
  7. Black, M., Richardson, M.: Germination of lettuce induced by inhibitors of protein synthesis. Planta (Berl.) 73, 344–356 (1967)Google Scholar
  8. Black, M., Bewley, J.D., Fountain, D.W.: Lettuce seed germination and cytokinins: their entry and formation. Planta (Berl.) 117, 145–152 (1974)Google Scholar
  9. Borthwick, H.A., Hendricks, S.B., Toole, E.H., Toole, V.K.: Action of light on lettuce seed germination. Bot. Gaz. 115, 205–225 (1954)CrossRefGoogle Scholar
  10. Brian, P.W., Hemming, H.G., Lowe, D.: Relative activity of the gibberellins. Nature 193, 946–948 (1962)Google Scholar
  11. Evenari, M., Neumann, G.: The germination of lettuce seed. II The influence of fruit coat, seed coat, and endosperm on germination. Bull. Res. Coun. Israel. 2, 15–17 (1952)Google Scholar
  12. Halmer, P., Bewley, J.D., Thorpe, T.A.: Enzyme to degrade lettuce endosperm cell wall during gibberellin- and light-induced germination. Nature (Lond.) 716–718 (1975)Google Scholar
  13. Ikuma, H., Thimann, K.V.: The role of the seed-coats in germination of photosensitive lettuce seeds. Plant and Cell Physiol. 4, 169–185 (1963)Google Scholar
  14. Ikuma, H., Thimann, K.V.: Analysis of germination processes of lettuce seed by means of temperature and anaerobiosis. Plant Physiol. 39, 756–767 (1964)Google Scholar
  15. Jones, R.L.: The structure of the lettuce endosperm. Planta (Berl.) 121, 133–146 (1974)Google Scholar
  16. Kahn, A., Goss, J.A., Smith, D.E.: Effects of gibberellin on germination of lettuce seeds. Science 125, 645–646 (1957)Google Scholar
  17. Kapoor, V.P.: A galactomannan from the seeds of Delonix regia. Phytochem. 11, 1129–1132 (1972)CrossRefGoogle Scholar
  18. Khan, A.A.: Inhibition of gibberellic acid-induced germination by abscisic acid and reversal by cytokinins. Plant Physiol. 43, 1463–1465 (1968)Google Scholar
  19. Lona, F.: L'acido gibberellico determina la germinazione dei semi di Lactuca scariola in fase di skotoinhibizoine. Ateneo parmense 27, 641–644 (1956)Google Scholar
  20. McCleary, B.V., Matheson, N.K.: Galactomannan structure and β-mannanase and β-mannosidase activity in germinating legume seeds. Phytochem. 14, 1187–1194 (1975)CrossRefGoogle Scholar
  21. Meier, H.: On the structure of cell walls and cell wall mannans from ivory nuts and from dates. Biochim. Biophys. Acta 28, 229–240 (1958)CrossRefPubMedGoogle Scholar
  22. Nabors, M.W., Lang, A.: The growth physics and water relations of red light-induced germination in lettuce seeds. 1: Embryos germinating in osmoticum. Planta (Berl.) 101, 1–25 (1971a)Google Scholar
  23. Nabors, M.W., Lang, A.: The growth physics and water relations of red light-induced germination in lettuce seeds. II: Embryos germinating in water. Planta (Berl.) 101, 26–42 (1971b)Google Scholar
  24. Nabors, M.W., Kugrens, P., Ross, C.: Photodormant lettuce seeds: Phytochrome-induced protein and lipid degradation. Planta (Berl.) 117, 361–365 (1974)Google Scholar
  25. Negbi, M., Black, M., Bewley, J.D.: Far-red sensitive dark processes essential for light- and gibberellin-induced germination of lettuce seed. Plant Physiol.43, 35–40 (1968)Google Scholar
  26. Park, W.M., Chen, S.S.C.: Patterns of food utilization by the germinating lettuce seed. Plant Physiol. 53, 64–66 (1974)Google Scholar
  27. Paulson, R.E., Srivastava, L.M.: The fine structure of the embryo of Lactuca sativa. I: Dry embryo. Canad. J. Bot. 46, 1437–1445 (1968)Google Scholar
  28. Pavlista, A.D., Valdovinos, J.G.: Carboxymethylcellulase activity prior to the onset of germination of lettuce seeds. Plant Physiol. 56 (suppl.), 83 (1975)Google Scholar
  29. Reynolds, T., Thompson, R.A.: Effects of kinetin, gibberellins and (±) abscisic acid on the germination of lettuce (Lactuca sativa). Physiol. Plant. 28, 516–522 (1973)Google Scholar
  30. Scheibe, J., Lang, A.: Lettuce seed germination: evidence for a reversible light-induced increase in growth potential and for phytochrome mediation of the low temperature effect. Plant Physiol. 40, 485–492 (1965)Google Scholar
  31. Thompson, J.L., Jones, J.K.N.: The glucomannan of bluebell seed (Scylla nonscripta L.). Canad. J. Chem. 42, 1088–1091 (1964)Google Scholar
  32. Thompson, R.C., Kosar, W.F.: The germination of lettuce seed stimulated by chemical treatment. Science 87, 218–219 (1938)Google Scholar
  33. Wolfrom, M.L., Laver, M.L., Patin, D.L.: Carbohydrates of the coffee bean. II Isolation and characterisation of a mannan. J. Org. Chem. 26, 4533–4535 (1961)Google Scholar

Copyright information

© Springer-Verlag 1976

Authors and Affiliations

  • P. Halmer
    • 1
  • J. D. Bewley
    • 1
  • T. A. Thorpe
    • 1
  1. 1.Department of BiologyUniversity of CalgaryCalgaryCanada

Personalised recommendations