ЭлБиб

201 / 592

PRO LO NG ED CULTIVATION OF SOMATIC PLA N T C ELL
SOMEPECULIARITIES OFTHEGENOMEEVOLUTION INCULTURED
PLANT CELLS
V.A .Kunakh
Institute ofMolecular Biology and Genetics NAS Ukraine, 252143 Kyiv, Zabolotnogo str.,
150,
Plant cell genomes in culture in vitro appear to come through the
considerable genome rearrangements. Levels, types, underlying reasons
and mechanisms fo r the genome variability and the course (pattern) of
selection (at various steps of cell culturing) tend to be various. During the
callus formation induction (dedifferentiation) there take place both the
reprogramming of the genome and alteration of its structure indicating the
regressive cell evolution. The initiation of the passaged cultures suggests
the adaptation of the cells to the environmental conditions extending beyond
the ranges of the genome norm reactions thereof. A t the early steps this
results in the p re fe rrential activities of the destabilizing selection, the dramatic
enhancement of the genetic variability. Further on as a manifestation of the
pressure of the newly-set environment the direrctional variety of the selection
comes into play. The established passaged populations are characteristic
of the occurrence of both physiological and genetic homeostasis, arising
from the effect of the stabilizing selection. Genome modifications were found
to occur at different steps o f the cell culturing thus suggesting the putative
parallelism in the genome evolution in culture in vitro and those in nature.
It is speculated that the cultured plant cells may serve as a model fo r
studies on the details of the genome evolution upon switch from one level of
the population organization to another, from multicellularto unicellular, from
panm icticto clonal one and vice versa.
2 0 1
Научная электронная библиотека ЦНСХБ