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E E Stupak

Publications and source records attributed to E E Stupak.

5 recordsLinked to original sources

Inheritance and state switching of genetic toggle switch in different culture growth phases.

Using the gene engineering methods, one can construct simple artificial gene networks with two stable functioning regimes (bistable genetic systems). Such genetic systems make it possible for cells with identical genotype to inherit two alternative phenotypes. The toggle switch is just one of the types of bistable genetic systems. In this work, we investigate the inheritance and switching of toggle switch functioning regimes in the cells at different culture growth phases. It is shown that during transition into the stationary growth phase the inheritance of stable states is disturbed and variations in the toggle-switching rate are more possible in different cells. Also, simultaneous expression of two genes of the system has been experimentally modelled. According to our results, the culture growth phase in this period determines later on the ratio between cell phenotypes in a population.

Escherichia coli↗

Epigenes: design and construction of new hereditary units.

A plasmid digene construction designed before [Tchuraev, R.N. (1982) J. Gen. Biol. 43, 79-87] has been realised, including feedback by repressing proteins with given trigger regime of gene functioning. Experimental tests of the expected epigene properties of the obtained pECPI recombinant plasmid involving lacI and cI(857) regulatory genes have shown a phenomenon of steady inheritance of two alternative epigenotypes lacI(1)cI(0) and lacI(0)cI(1), as well as an external toggle switch through metabolitic and temperature signals from one inherited functional state of the cyclic digene system into another. Thus, we have constructed a hereditary unit of a specific kind, namely, a two-component stationary epigene with preset properties.

Bacterial Proteins↗

[Construction of an artificial digenic network with epigenetic properties].

A model of the simplest epigene was constructed to have two alternative states, which proved to be stable and transmittable through Escherichia coli cell generations. A switch from one to another state was induced by thermal and chemical external signals. The results gave further insight into the dynamic mechanism of preservation, coding, and transmission of the genetic information.

Bacterial Proteins↗