Aging in humans and fruit flies: another common gene

Scientists working under the guidance of Doctors Lynne Cox and Robert Saunders from Oxford and the Open University (Great Britain) have identified a gene in the genome of fruit flies that makes these insects a convenient model for studying human aging processes at the cellular, genetic and biochemical levels.

The authors are studying Werner syndrome, a disease that causes premature aging of a person, in order to understand in more detail the mechanisms of normal aging. The cause of this disease is a mutation of the WRN gene. Scientists have made great progress in studying the effects of the functioning of this gene (its main role is to prevent errors in the recombination of DNA sections during cell division), but until now they have studied the functions of WRN in cell cultures and have not been able to observe its effect on the development of the whole organism.

Researchers have identified the equivalent of the human WRN gene in the genome of fruit flies. In addition, it turned out that insects with damage to this gene have symptoms similar to the manifestations of Werner syndrome. In particular, in drosophila with a damaged WRN gene, there is instability of chromosomes and, accordingly, their damage, as well as the movement of genes from chromosome to chromosome. In people with Werner syndrome, such genome instability contributes to the development of cancer. The cells of patients with this disease are extremely sensitive to the anti-cancer drug camptothecin (camptothecin). This natural alkaloid exhibits a cytotoxic effect, suppressing the work of the enzyme topoisomerase 1 (topoisomerase I), which is necessary at one of the first stages of DNA replication. Researchers have demonstrated that even negligible doses of this drug are fatal for fruit flies with WRN gene mutations.

Geneticists have been using fruit flies as a model for studying the genetic mechanisms underlying the normal functioning of the human body for a very long time. Therefore, the opportunity to work with these well-known organisms in the study of aging processes is very good news for specialists working in this field.

Article by Saunders et al. Identification and characterization of a Drosophila orthologue of WRN exonuclease that is required to maintain genome integrity is published in the open access journal Aging Cell.

Portal "Eternal youth" www.vechnayamolodost.ru based on the materials of ScienceDaily

14.05.2008