Summary
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.
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Abbreviations
- ABA:
-
abscisic acid
- BA:
-
benzyladenine
- GA:
-
gibberellic acid
References
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)
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)
Bewley, J.D., Black, M.: Protein synthesis during gibberellin induced germination of lettuce seed. Canad. J. Bot. 50, 53–59 (1972)
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)
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)
Black, M.: Light controlled germination of seeds. In: Symp. Soc. exp. Biol. 23, 193–218 (1969)
Black, M., Richardson, M.: Germination of lettuce induced by inhibitors of protein synthesis. Planta (Berl.) 73, 344–356 (1967)
Black, M., Bewley, J.D., Fountain, D.W.: Lettuce seed germination and cytokinins: their entry and formation. Planta (Berl.) 117, 145–152 (1974)
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)
Brian, P.W., Hemming, H.G., Lowe, D.: Relative activity of the gibberellins. Nature 193, 946–948 (1962)
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)
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)
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)
Ikuma, H., Thimann, K.V.: Analysis of germination processes of lettuce seed by means of temperature and anaerobiosis. Plant Physiol. 39, 756–767 (1964)
Jones, R.L.: The structure of the lettuce endosperm. Planta (Berl.) 121, 133–146 (1974)
Kahn, A., Goss, J.A., Smith, D.E.: Effects of gibberellin on germination of lettuce seeds. Science 125, 645–646 (1957)
Kapoor, V.P.: A galactomannan from the seeds of Delonix regia. Phytochem. 11, 1129–1132 (1972)
Khan, A.A.: Inhibition of gibberellic acid-induced germination by abscisic acid and reversal by cytokinins. Plant Physiol. 43, 1463–1465 (1968)
Lona, F.: L'acido gibberellico determina la germinazione dei semi di Lactuca scariola in fase di skotoinhibizoine. Ateneo parmense 27, 641–644 (1956)
McCleary, B.V., Matheson, N.K.: Galactomannan structure and β-mannanase and β-mannosidase activity in germinating legume seeds. Phytochem. 14, 1187–1194 (1975)
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)
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)
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)
Nabors, M.W., Kugrens, P., Ross, C.: Photodormant lettuce seeds: Phytochrome-induced protein and lipid degradation. Planta (Berl.) 117, 361–365 (1974)
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)
Park, W.M., Chen, S.S.C.: Patterns of food utilization by the germinating lettuce seed. Plant Physiol. 53, 64–66 (1974)
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)
Pavlista, A.D., Valdovinos, J.G.: Carboxymethylcellulase activity prior to the onset of germination of lettuce seeds. Plant Physiol. 56 (suppl.), 83 (1975)
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)
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)
Thompson, J.L., Jones, J.K.N.: The glucomannan of bluebell seed (Scylla nonscripta L.). Canad. J. Chem. 42, 1088–1091 (1964)
Thompson, R.C., Kosar, W.F.: The germination of lettuce seed stimulated by chemical treatment. Science 87, 218–219 (1938)
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)
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Halmer, P., Bewley, J.D. & Thorpe, T.A. An enzyme to degrade lettuce endosperm cell walls. Appearance of a mannanase following phytochrome- and gibberellin-induced germination. Planta 130, 189–196 (1976). https://doi.org/10.1007/BF00384419
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DOI: https://doi.org/10.1007/BF00384419