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Genetic engineering as a subject of public debates has been winning more and more space in the mass media over the past few years. And the emphasis, woe and behold, has been less on the potential benefits of this branch of modem research to the suffering mankind in its struggle against disease and genetic disorders and in its efforts to develop new plants and animals with new and improved characteristics. What we hear of as often as not is about some really frightening prospects of this research and experiments conducted here and there with or without formal approval. But, as we all know from historical experience, time will finally put all of these things in their proper place and perspective. A leading expert in this field of research, Corresponding Member of the Russian Academy of Sciences and Director of the RAS Siberian Institute of Plant Physiology and Biochemistry, Rurik Salyaev, summed up his views on the problem in a recent interview which we are quoting now.
So, what can we expect from genetic engineering at the current state of the art?
The most immediate, and humane tasks before this science is combating disease and boosting food production. In this country, for example, there is a shortage of "domestic"
insulin, a drug which is daily required for large numbers of patients. And although we do have genetic engineering technologies of insulin manufacture, large-scale production of the drug is still a thing of the future.
And there are also other genetic engineering technologies for manufacturing new medicinal and veterinary preparations. Take, for example, the production of genetic engineering vaccines against such dangerous ailments as rabbis, tuberculosis, hepatitis and suchlike infections.
In recent time there have appeared new possibilities for developing "edible" vaccines on the basis of transgenic plants. This very promising area calls for the concerted efforts of medical experts, molecular biologists and specialists in genetic engineering.
What concerns transgenic plants, progress in this area has been really impressive. This is largely due to the fact that the problem of developing an organism from a cell, group of cells or "immature" buds of plants lends itself to some practical and not too complicated solutions. Cell technologies, tissue cultures and development of what we call regenerants have become common practice in modem science.
In 1999 we hosted an All-Russia symposium at our Siberian Institute of Plant Physiology and Biochemistry on the subject of genome studies and studies of genetic transformation of plants. The forum demonstrated that vigorous research into genetic engineering of plants is now under way in the research centers of Moscow, St. Petersburg, Saratov, Ufa, Kazan, Novosibirsk, Irkutsk and Vladivostok. The results already available now can provide a basis for developing new plant forms with new and improved characteristics. Take, for example, the results of studies of the genome of plants and development of new transgenic forms obtained by scientists in Novosibirsk over the past 5 to 7 years.
One quite unexpected result of the studies of the mitochondrial* genome has been the discovery of nonrandom homologies (identity) of fragments of mitochondrial DNA with the DNA of some dangerous viruses.
The degree of homology of fragments of mitochondrial DNA of maize with the hepatitis A virus reaches 89 percent and is 89.5 percent with the virus of В influenza (Singapore). Sites with lesser degree of homology have been found homologous with the DNA of Punta toro phlebovirus, the retrovirus of birds. The genetic engineering lab of the Institute, which carried out these studies, has so far been unable to explain its findings. Is this something accidental? Nor can we explain how this nucleotide sequence was formed in the mitochondrial DNA of plants. Could it be that the fragments of mitochindrial DNA (and probably other DNAs) which were singled out in the process of the evolution were somehow "built in" into the mitochonrial genome?
Over the past few years scientists of the Siberian Institute of Plant Physiology and Biochemistry obtained several transgenic plants by implanting into their genome of genes ugt, acp, acb, accc and several others isolated from various plant objects. Institute specialists are working with plant genes so as to rule out any doubts concerning the "edibility" of such transgenic plant forms.
* Mitochondria - any of various round or long cellular organelles that are found outside the nucleus, produce energy for the cell through cellular respiration and are rich in fats, proteins and enzymes. - Ed.
The genes were introduced either by "firing" at tissues from a "gene gun" (designed and built by our staff) or by means of a genetic vector on the basis of agrobacterial plasmid, possessing "built-in" targeted genes and the appropriate promoters.
Adequite control was provided for the "incorporation" of the special-purpose and marker genes and their expression in the transgenic plants. A number of new transgenic forms have been produced as a result, including transgenic wheat (two varieties). It features rapid growth and tillering and is more resistant to droughts and other adverse factors of the environment. Experts are now assessing its crop yields and hereditary factors.
Transgenic potato, which has been under observations for the past three years now, boasts yields which are 50 to 90 percent higher that the norm. It features practically complete stability towards herbicides of the auxin range and its tubers do not "blacken" so much at the cuts due to a reduced activity of polyphenol oxidase.
New transgenic tomatoes (several varieties) also feature increased tillering and cropyields. In hothouses they yield up to 46 kg/m 2 (which is twice as much as the control).
Transgenic cucumbers (several varieties) feature a greater number of fertile buds and, consequently, greater yields of up to 21 kg/m 2 as against 13.7 in the control.
While working on transgenic aspen, we assumed that by introducing ugt and acb genes we shall be able to alter in a desirable way the hormonal status of the plant (lipid metabolism) and produce some faster growing varieties. These could be used as the basis for rapidly growing tree plantations which could be planted without felling away the valuable patches of taiga forests which are of planetary ecological importance. And such "instant" plantations would be more attractive economically since they could be located next to the processing plants, doing away with transportation costs and providing for a more complete utilization of timber.
The transgenic asp gave us quite a surprise. Observed already in vitro in the culture medium was its more intensive growth which was even more impressive when planted into vegetation boxes.
With the introduction of ugt gene from maize its growth was 2.5 times greater than of the control, and with the introduction of ugt and acb genes it was 5 times greater than the control.
When the plants were moved onto an open-air test site, the growth increase was preserved, though on a smaller scale.
The plants are now 4 years old and the transgenic species are growing much faster than the control and with time we shall be able to draw final conclusions about the new varieties.
Our Institute scientists have on their record more than 30 transgenic plants with which they are still working now. And we are in no hurry to offer our new "products", even the best of them, to commercial users. This is because we feel we need to solve a whole range of additional problems concerning the stability of the introduced genes, and the "heredity" of the new and improved parameters. And we have to keep up our studies on their biochemical and physiological characteristics.
These studies at our Institute are conducted now by three labs: of cell physiology, genetic engineering and transgenic plant physiology.
Summing it up, one can say that genetic engineering is a science of both today and tomorrow. Even now tens of millions hectares are occupied by transgenic crops which provide the basis for new medicinal preparations and other useful substances. As time goes by, genetic engineering will evolve into an even more powerful instrument for progress and achievements in medicine, veterinary science, pharmacology, food industry and farming.
Nauka v Sibiri (Science in Siberia), 2001
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