Polyamines and Aging: Effect of Polyamine Biosynthetic Inhibitors on Plant Regeneration in Maize Callus Cultured in Vitro
Culture age is an important factor in expressing the genetic potential of plant cells and tissues in vitro, since it is well known that many cultures lose their morphogenetic capacity as they aged (Vasil et al., 1984). Although the precise biochemical and molecular mechanisms underlying the gradual loss of totipotency are not known, some compounds such as polyamines (PAs) are involved in these phenomena. Thus, the diamine putrescine (Put), the triamine spermidine (Spd), the tetraamine spermine (Spm), and their biosynthetic enzyme arginine decarboxylase (ADC) are biochemical markers of both plant cell aging and plant cell differentiation. In senescing leaves of cereals incubated in darkness both the ADC activity and the endogenous PA levels progressively decrease, while exogenous application of PAs, especially Spd and Spm, inhibits or retards the symptoms of senescence (Kaur-Sawhhey et al., 1979; 1982). On the other hand, using tobacco thin cell layer cultures (TCL; Tran Thanh Van, 1973) we have demonstrated that Spd is a marker of floral differentiation (Tiburcio et al., 1987; 1988; Kaur-Sawhney et al., 1988), while the Put formed via ADC is a marker of root differentiation (Tiburcio et al., 1989a).
KeywordsLeaf Senescence Polyamine Metabolism Anti Senescence Effect Diamine Putrescine Maize Callus
Unable to display preview. Download preview PDF.
- Carbonell, J., and Navarro, J.L., 1989, Correlation of spermine level with ovary senescence and fruit set and development in Pisum sativum, Planta, (in press).Google Scholar
- Kaur-Sawhney, R., Shih, L.M., Cegielska, T., and Galston, A.W., 1982, Inhibition of protease activity by polyamines. Relevance for control of leaf senescence, FEBS Lett., 145:345.Google Scholar
- Slocum, R.D., and Galston, A.W., 1987, Inhibition of polyamine biosynthesis in plants and plant pathogenic fungi, in: “Inhibition of Polyamine Metabolism: Biological Significance and Basis for New Therapies”, P.P. McCann, A.E. Pegg and A. Sjoerdsma, eds., Academic Press, New York.Google Scholar
- Tiburcio, A.F., Kaur-Sawhney, R., and Galston, A.W., 1987, Regulation by polyamines of plant tissue culture development, in: “Advances in the Chemical Manipulation of Plant Tissue Cultures”, M.B. Jackson, S.H. Mantell and J. Blake, eds., British Plant Growth Regulator Group, Bristol.Google Scholar
- Tiburcio, A.F., Kaur-Sawhney, R., and Galston, A.W., 1988, Polyamine biosynthesis during vegetative and floral bud differentiation in thin layer tobacco tissue cultures, Plant Cell Physiol., 29:1241.Google Scholar
- Tiburcio, A.F., Gendy, C.A., and Tran Thanh Van, K., 1989a, Morphogenesis in tobacco subepidermal cells: putrescine as marker of root differentiation, Plant Cell Tiss. Org. Cult., (in press).Google Scholar
- Tiburcio, A.F., Kaur-Sawhney, R., and Galston, A.W., 1989b, Polyamine metabolism, in: “The Biochemistry of Plants. A Comprehensive Treatise,” B.J. Miflin, ed., Academic Press, New York, (in press).Google Scholar