The proliferative growth of thin cell layers of Nicotiana tabacum cultured on a rhizogenic medium was markedly disturbed when polyamine biosynthesis was inhibited. Treatments with polyamine inhibitors led to cell expansion, accompanied by thinning of the cell wall and inhibition of cell division, and frequent cases of nucleolar extrusion, mainly in the parenchymal layer in contact with the medium. Nucleolar extrusion was not correlated with cell expansion. The highest incidence of nucleolar extrusion occurred when the pathways of putrescine biosynthesis were inhibited and when spermidine synthesis, via S-adenosylmethionine decarboxylase, was blocked. The duration of the growth phase with nuclear amitotic divisions was prolonged in the presence of the inhibitors and root meristem formation delayed. When polyamines were added with the inhibitors, all reactions proceeded as in the controls.
Cytological events induced by the inhibition of polyamine biosynthesis in thin cell layers of tobacco / Altamura, Maria Maddalena; Capitani, Francesca; R., Cerchia; Falasca, Giuseppina; N., Bagni. - In: PROTOPLASMA. - ISSN 0033-183X. - STAMPA. - 175:1-2(1993), pp. 9-16. [10.1007/bf01403280]
Cytological events induced by the inhibition of polyamine biosynthesis in thin cell layers of tobacco
ALTAMURA, Maria Maddalena;CAPITANI, Francesca;FALASCA, Giuseppina;
1993
Abstract
The proliferative growth of thin cell layers of Nicotiana tabacum cultured on a rhizogenic medium was markedly disturbed when polyamine biosynthesis was inhibited. Treatments with polyamine inhibitors led to cell expansion, accompanied by thinning of the cell wall and inhibition of cell division, and frequent cases of nucleolar extrusion, mainly in the parenchymal layer in contact with the medium. Nucleolar extrusion was not correlated with cell expansion. The highest incidence of nucleolar extrusion occurred when the pathways of putrescine biosynthesis were inhibited and when spermidine synthesis, via S-adenosylmethionine decarboxylase, was blocked. The duration of the growth phase with nuclear amitotic divisions was prolonged in the presence of the inhibitors and root meristem formation delayed. When polyamines were added with the inhibitors, all reactions proceeded as in the controls.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.