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Standard survival analysis involves consideration of the proportion of live individuals in the cohort at a specific time point. We propose to analyze the dependence of survival variance on cohort age. This approach allowed us to identify several age periods in the ontogenesis of Drosophila melanogaster. The first two are approximated by an exponential equation, and the later ones are approximated by a sigmoid curve. The parameters of these curves can be changed under short-term (11 days) and long-term (22 days) exposure to low temperature, as well as with the addition of Cytoflavin to the nutrient medium. The proposed approach, in our opinion, makes it possible to search for “age-associated” geroprotective effects.

We analyze the regression of survivability variance by cohort age in several generations of Drosophila melanogaster Canton-S stock. This estimation reflects survivability reaction norm. Three phases were detected. First and second was approximated by exponential equation and the third - by logistic dose-response curve. Parameters of the equations remains stable for decades and thus must have high heritability.

The rearing of Drosophila fruit flies at a temperature 5–7°C lower than the standard level until day 13 (or day 22) of the imaginal period enabled an increase of the individual insect lifespan. The positive effect of the longest exposure was evident in all age groups. This effect was due to prolongation of the initial period of the individuals’ lives and the subsequent delay of the onset of later developmental stages. The observed phenomenon may result in delayed development of aging-related pathology and a significant increase in the object’s maximal lifespan. The effect was independent of sample size (in samples of 100 to 1200 flies) and the interval between the experiments. All individuals of the cohort are assumed to contribute to the phenomenon.

The frequencies of disk sequences in the polytene chromosomes from the salivary glands of the larvae of three species of chironomids (Diptera, Chironomidae) are analyzed. Statistically significant deviations of the population structure from the structure expected by the Hardy-Weinberg equilibrium law are detected. The distribution of frequencies in individuals with different levels of heterozygosity in the Camptochironomus tentans populations is examined. The influences of the driving and stabilizing selection on the population’s genotype are uncovered. A methodology for estimating the influence of different disk sequences on the species’ adaptability based on single collections is proposed. The stability of the nonequilibrium in the studied populations is noted and interpreted as a sign of homeostasis.

The validity of the two-component structure of annuity curves in Drosophila melanogaster (line Canton-S) observed in our previous studies has been confirmed. The structure is formed by a combination of a stable five-phase pattern and the variability of phase duration (the latter determines the variability of insect viability). Both the stable and the variable component were preserved over 60 generations of flies. The unconventional type of variability addressed in the present study exists along with the well-known type of variability related to the stochastic variation of the annuity curves. The variance of viability that characterizes the reaction norm remains unchanged in a series of generations as well. Thus, both types of variability can be classified as genetically determined phenomena.

We analyze the regression of survivability variance by cohort age in several generations of Drosophila melanogaster Canton-S stock. Three phases were detected. First and second was approximated by exponential equation and the third - by logistic dose-response curve. Parameters of the equations can be influenced by short (11 days) and long (22 days) action of low temperature (21 °C) or by long-term diet of cytophlavin preparation, containing succinic acid. We argue, that such approach can help to detect age-specific geroprotectors and better detect geroprotector impact mechanisms.Стандартный анализ выживаемости предполагает учет доли живых особей в когорте на определенный момент времени. Мы предлагаем анализировать зависимость дисперсии выживаемости от возраста когорты. Такой подход позволил выявить несколько возрастных периодов в онтогенезе Drosophila melanogaster. Первые два аппроксимируются экспоненциальным уравнением, а последующие — сигмоидной кривой. Параметры этих кривых могут быть изменены при кратковременном (11 дней), долговременном (22 дня) действии пониженной температуры, а также при добавлении в питательную среду препарата «Цитофлавин». Предлагаемый подход, по нашему мнению, позволяет вести поиск «возрастных» геропротективных воздействий.

We analyze the regression of survivability variance by cohort age in several generations of Drosophila melanogaster Canton-S stock. This estimation reflects survivability reaction norm. Three phases were detected. First and second was approximated by exponential equation and the third - by logistic dose-response curve. Parameters of the equations remains stable for decades and thus must have high heritability.Стандартный анализ выживаемости предполагает учет доли живых особей в когорте на определенный момент времени. Предложено анализировать зависимость дисперсии выживаемости от возраста когорты. Этот показатель отражает норму реакции признака «выживаемость». Такой подход позволяет выявить как минимум три возрастных периода у Drosophila melanogaster. Первые два периода могут быть описаны экспоненциальным уравнением, третий — логистическим. Параметры этих уравнений сохраняют стабильность на протяжении десятков поколений и, таким образом, должны быть жестко генетически детерминированы.

Frequencies of disk sequences in polytene chromosomes from sialadens of larvae of three chironomids spesies are analysed. Cases of a deflection of population frame from expected under Hardy-Vajnberg law are statistically confirmed. Allo-cation of frequencies of individuals with different level of heterozygosity in popu-lation of Camptochironomus tentans is investigated. Influence of driving and stabi-lising selection on population is shown. The mean of an assessment of influence of different disk sequences on fitness on the basis of single assemblies is offered. Sta-bility of nonequilibrium of the investigated populations as a homeostasis sign is noted.

The five-phase structure of annuity curves for fruit flies of the Canton-S line detected earlier has been observed at different cohort sizes, which is indicative of the stability of the feature in question. However, variability in the duration of each of the five phases and a related variability in the cohort lifespan was observed in five experimental replicates. The five-phase structure is assumed to be under rigid genetic control, whereas the certain variability in the phase duration (which determines lifespan variability) implemented in the program of fruit fly development is presumably affected by weak uncontrollable signals.

Analysis of the age-specific mortality dynamics in the male imago of the Drosophila melanogaster Canton-S strain demonstrated pronounced deviations from the Gompertz law. Four successive observations carried out in large drosophila cohorts made it possible to determine that the survival curves of the objects within the cohort lifetime consist of five discrete regions (phases) divided by sharp inflections. All of the indicated regions are linear. A rigid genetic determination for the disclosed character of the investigated curves was hypothesized.

The article deals with the analysis of Russian legal policy in the sphere of genetic engineering. Over the past ten years, the risks of genetic engineering in the Russian society are mythologized. At the same time attempts were made to change the model of the legal regulation of genetic engineering legislation to tighten it. They worried the scientific community. At the same time the legislative initiatives to tighten the model of the legal regulation of genetic engineering become frequent. This situation worries the scientific community. The authors explore the goals which the Russian legislator aims in the process of legal regulation of genetic engineering, and relate them to the needs of the development of science. The authors identified two problems in the teleology of the Russian legal policy in the field of genetic engineering. Firstly, the concept of national biosafety has not been created. This concept is necessary for specifying not only negative but also positive risks of genetic engineering, that is, for the purposes of definition the use of genetic engineering. Second, the degree of influence of the scientific community to the social representations about the risks of genetic engineering is weak.

The frequency of the contacts between polytene chromosomes via their centromeric and telomeric regions in the karyotype of the non-biting midge Prodiamesa olivacea has been analyzed. The fact that the groups of centromeric contacts are nonrandom and match the diploid chromosome number, equal to ten, has been statistically confirmed. The species is announced as a transitional form that evolves towards a reduction in the chromosome number.

The frequency of contacts of centromere and telomere regions of polytene chromosomes in the karyotype of a midge Prodiamesa olivacea has been analyzed. The fact of non-random frequency of centromere regions contacts has been confirmed by statistical methods. These data are consistent with the diploid number of chromosomes equal to 10. The species has been announced as a “transitional form”, evolving towards reduction of the chromosome number.

We confirm five-phased construction of Drosophila annuity curves established earlier. Annuity curves were composed of stable five-phase component and variable one. Variable component was due to differences in phase durations. As stable, so variable components were apparent for 60 generations. Stochastic component was described as well. Viability variance which characterize «reaction norm» was apparent for all generation as well. Thus, both types of variability seem to be inherited.Подтверждена реальность установленной ранее двухкомпонентной конструкции кривых дожития у Drosophila melanogaster линии Canton-S. Конструкция состоит в комбинации стабильной пятифазной структуры с изменчивой длительностью фаз (что определяет вариабельность жизнеспособности насекомых). Как стабильная, так и изменчивая компонента сохранилась на протяжении 60 поколений мух. Указанная необычная форма изменчивости существует наряду с известной ее формой, обусловленной стохастическим разбросом кривых дожития. Дисперсия жизнеспособности, характеризующая норму реакции, также не изменяется в ряду поколений. Таким образом, обе формы изменчивости могут быть отнесены к категории наследственно детерминированных явлений.

Analysis of male imago mortality in Drosophila melanogaster Canton-S strain demonstrated deviation from Gompertz law. Annuity curves were composed of five phases divided by sharp bends. All the phases seemed to be linear. We discuss the hypotheses of strict genetic determination of the phenomenon.При анализе динамики возрастной смертности имаго дрозофил линии Canton-S зарегистрированы выраженные отклонения от закона Гомпертца. В четырех последовательных наблюдениях, проведенных на когортах дрозофил большой численности, обнаружено, что кривые дожития объектов на протяжении жизни когорт состоят из пяти дискретных участков (фаз), разделенных крутыми перегибами. Все указанные участки имеют линейный характер. Выдвинута гипотеза о жесткой генетической детерминации обнаруженного характера исследованных кривых.

Synthetic epithalon demonstrates differences in the antimutagenic activity after cyclophosphamide injection in mice with different hair color. We demonstrated protective effects in white mice, but not in grey ones. These effects may be explained by the different neuro-humoral status and stress-resistance of the animals.

To characterize survival curves, we suggest calculating the following three parameters: median life span, the slope of the survival curve, and expected maximum life span. Using these parameters, geroprotectors can be classified as weak, moderate, and strong.

Epitalon demonstrate differences in antimutagenic activity after cyclophosphamide injection in mice. We demonstarted protection effects in white mice, but not in grey ones. Those effects may be explained by different neuro-humoral status and stress-resistance of the animals.

We performed comparative genetic analysis of a set of synthetic peptides effects on longevity and free-radical oxidation in Drosophila melanogaster. Strong genotype and gene-environmental interaction in determining traits value were evaluated. Mechanisms of vilon and epithalon effect on free oxygen species in mitochondria seemed to be different.

The results of three long-term breeding and genetic experiments with Drosophila melanogaster performed at different times are summarized. Selections for different fitness components led to similar results. The data on the concentration of viability mutations in the inbred strains LA, LA+, and LA− after 400 generations of selection and the strain ULA during its breeding are presented for the first time. The results of studying the genetic heterogeneity and spontaneous mutational process in Drosophila inbred strains comply with the idea of M.E. Lobashev that “a change in the direction of selection or acceleration of its rate is always accompanied by a concurrent increase in mutational variation.”

The purpose of the course "Genetic mechanisms of individual and cooperative adaptation" (12 semester 18 hours) - is to provide students with a broad view in population mechanisms of the different types of adaptation. The problem of the course consists in benchmark analysis of the ways and mechanisms of the origin of these adaptations, as well as in their possible macroevolution consequence. The individual adaptation is considered on model of stressful influence on populations. Cooperative adaptation is considered basically on model of symbiosis, whose formation associates with origin of new traits, which greatly increase evolution potential of biological species. The course develops the knowledge obtained from prerequisite courses, such as "General genetics" "Symbiogenetics", "General ecology" and "Theory of evolution".

The antioxidant capacity of red cloudberry (Rubus chamaemorus) juice correlates well with its phenolic content. The red berries have a markedly higher content of anthocyanins, particularly cyanidin and pelargonidin derivatives, than that found in the more common yellow fruit. Conversely, the yellow juice has higher ellagitannin content. A feeding study was conducted to show the in vivo effects of the juices on lipid peroxidation in a sensitive Drosophila melanogaster stock. In young female flies there were significant (P < 0.01) effects of cloudberry juice on lipid peroxidation. In young male flies significant (P < 0.05) effects were found on primary products (hydroxyperoxides) with yellow juice and on secondary products (ketodienes) with red juice. With the red juice, a significant (P < 0.05) decrease in ketodienes was found in both young and old males. This study demonstrates that the effects of berry antioxidants on lipid peroxidation are easily and rapidly tested in vivo with the sensitive Drosophila model.

We studied the effects of Epithalon (Ala-Glu-Asp-Gly) and Vilon (Lys-Glu) on free radical processes in highly inbred HA(+)line of Drosophila melanogaster. Vilon inhibited generation of reactive oxygen species in mitochondria, but stimulated this process in the cytosol. We found sex- and age-related differences in the generation of reactive oxygen species and cytosol antioxidant activity.

The effect of epithalone on the age-specific time course of lipid peroxidation was studied in inadaptiveDrosophila melanogaster strains. A single dose of epithalone at the larval stage decreased the level of conjugated hydroperoxides and Schiff bases throughout the life span of imago. Strain- and sex-specific differences in the time course of the studied sign are characterized.

Treatment with pineal peptide preparation epithalamin was followed by the increase of the mean lifespan of female D. melanogaster, SHR mice, C3H/Sn mice and LIO rats by 11-31% (P < 0.05). Ninety percent mortality as well as maximum lifespan were increased in fruit flies, C3H/Sn mice and rats. Mortality rate was decreased by 52% in D. melanogaster, by 52% in rats, by 27% in C3H/Sn mice. It did not change in SHR mice exposed to epithalamin. Treatment with the pineal peptide increased MRDT in flies, C3H/Sn mice and rats. It has been shown that epithalamin increased synthesis and secretion of melatonin in rats and inhibits free radical processes in rats and in D. melanogaster. It is suggested that antioxidative properties of epithalamin lead to increased lifespan of three different animal species.

General and specific effects of molecular genetic responses to adverse environmental factors are not well understood. This study examines genome-wide gene expression profiles of Drosophila melanogaster in response to ionizing radiation, formaldehyde, toluene, and 2,3,7,8-tetrachlorodibenzo-p-dioxin. We performed RNA-seq analysis on 25,415 transcripts to measure the change in gene expression in males and females separately. An analysis of the genes unique to each treatment yielded a list of genes as a gene expression signature. In the case of radiation exposure, both sexes exhibited a reproducible increase in their expression of the transcription factors sugarbabe and tramtrack. The influence of dioxin up-regulated metabolic genes, such as anachronism, CG16727, and several genes with unknown function. Toluene activated a gene involved in the response to the toxins, Cyp12d1-p; the transcription factor Fer3’s gene; the metabolic genes CG2065, CG30427, and CG34447; and the genes Spn28Da and Spn3, which are responsible for reproduction and immunity. All significantly differentially expressed genes, including those shared among the stressors, can be divided into gene groups using Gene Ontology Biological Process identifiers. These gene groups are related to defense response, biological regulation, the cell cycle, metabolic process, and circadian rhythms. KEGG molecular pathway analysis revealed alteration of the Notch signaling pathway, TGF-beta signaling pathway, proteasome, basal transcription factors, nucleotide excision repair, Jak-STAT signaling pathway, circadian rhythm, Hippo signaling pathway, mTOR signaling pathway, ribosome, mismatch repair, RNA polymerase, mRNA surveillance pathway, Hedgehog signaling pathway, and DNA replication genes. Females and, to a lesser extent, males actively metabolize xenobiotics by the action of cytochrome P450 when under the influence of dioxin and toluene. Finally, in this work we obtained gene expression signatures pollutants (dioxin, toluene), low dose of gamma-irradiation and common molecular pathways for different kind of stressors.

Effects of synthetic pineal tetrapeptide L-Ala-L-Glu-L-Asp-L-Glu (Epithalon) on specific catalase activity and the content of conjugated hydroperoxides in highly inbred Drosophila melanogaster lines differing in reproductive functions were studied. It was shown that Epithalon is a potent modulator of the antioxidant defense, whose biological activity 1000-fold surpasses that of the complex pineal peptide preparation Epithalamin.

It was shown previously that epithalamin delays age-related changes in reproductive and immune systems and increases the life span of mice and rats. These effects could be mediated by stimulating influences of epithalamin on synthesis and secretion of melatonin and on free radical processes. A comparative study on the effect of epithalamin and melatonin on both the life span of Drosophila melanogaster (strain HEM) and on the intensity of lipid peroxidation and activity of antioxidative enzymes in their tissues was the main aim of this work. Melatonin and epithalamin was added to the nutrition medium (100 micrograms/ml) during 2-3rd age of larvas. For survival analysis the flies were passed (five coupes per vessel) each 3-7 days. Lipid peroxidation was evaluated as the level of ketodienes (KD) and conjugated hydroperoxides (CHP) in fly tissues at the age of 11 days. Activity of Cu, Zn-superoxide dismuatse (SOD) and catalase was evaluated as well. The mean, median and maximum life span (MLS) were estimated. Mortality rate (MR) was calculated as alpha in the Gompertz equation (R = Ro (exp alpha t) and mortality rate doubling time (MRDT) as in 2/alpha. These parameters in groups of male and female flies exposed to melatonin and in male flies exposed to epithalamin were no different from the parameters for controls. However, exposure to epithalamin was followed in females by a significant increase in mean life span (by 17%, P < 0.02), of median (by 26%), of MLS by 14% and by a 2.12 times decrease of MR (P < 0.01) and MRDT (by 32%) compared with female controls. The level of CHP and KD in the tissues of male control flies was 40 and 49% less than that in females and indirectly correlates with male life span. Exposure to melatonin was followed by a decrease in the level of CHP and KD in females and the deletion of sex differences in them. Exposure to epithalamin significantly decreased the level of CHP and KD in female flies compared to controls (2.3 and 3.4 times, respectively, P < 0.001). Exposure to melatonin failed to influence the activity of catalase in males but increased it in females by 24% (P < 0.02) and failed to influence SOD activity both in males and females. Exposure to epithalamin was followed by a significant increase in activity of catalse, 20% in males and 7% in females and by an increase in SOD activity in males (41%). Thus, it was shown that exposure to epithalamin significantly increases the mean life span and MLS of female D.melanogaster and slowed down their aging rate by 2.12 times. This effect is in good agreement with the inhibiting effect of epithalamin in lipid peroxidation processes in fly tissues.