Biopolym. Cell. 1998; 14(4):298-319.
Genome variability in plant somatic cells. 4. Variability in the process of dedifferentiation and callus formation in vitro
1Kunakh V. A.
  1. Institute of Molecular Biology and Genetics, NAS of Ukraine
    150, Akademika Zabolotnoho Str., Kyiv, Ukraine, 03680


Peculiarities of the genome, variations upon induction of the dedifferentiation and callus formation events have been reviewed. Role of the genotype and the genome state in cells of the original explant, nutrient medium stimuli, determinants, mechanisms and possible ways to control these variations have been discussed. Initiation of the dedifferentiation processes and further cell proliferation was shown to suggest the reprogramming of the genome, «juvenilization» of its state. Genome regressive evolution in the course of the development of the dedifferentiation program was hypothesized. Capacity for such evolution seems to underly the differentiation–dedifferentiation–differentiation developmental cycle peculiar to many plants. Existence of such a cycle, its potential to be control-liable both in nature and experiment appear to question the concept about the programmed number of the cell cycles, the irreversibility of ageing, tile fatality of the programmed cell death and. apoptosis. Utmost importance and actuality of the studies on molecular mechanisms of the dedifferentiation and juvenilization processes in plants has been emphasized. Author believes that this would allow better understanding of the fundamental biological mechanisms involving ageing and death.


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