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Lushchak, O.

Publications and source records attributed to Lushchak, O..

3 recordsLinked to original sources

Reproduction and preference to macronutrients have different relations to biological or chronological age in Drosophila

Genetic manipulations, dietary composition and supplementations with varied drugs and natural compounds were shown to extend both the life- and health-span in different model organisms. An understanding of the mechanisms behind the beneficial properties of intervention includes the evaluation of physiological and molecular traits at certain time points that reflect the values at distinguished chronological age. Thus, if one cohort has a long-lived phenotype than measurements at certain time points represent the difference between organisms of different biological ages. We have compared reproduction and consumption of specific macronutrients for flies of the same cohort but related to different quartiles of chronological and biological age. We found that the decline in carbohydrate or protein consumption was stronger in the case of chronological rather than biological age. However, flies of biological or chronological quartile 4 consumed virtually the same amounts of macronutrients. The decline in reproduction was significantly reduced in relation to biological age. Thus, the decline was about 38-68% when within chronological quartiles 2 and 1 but only 4-31% for biological ones. The reproductive capacity was reduced by 86-93% in flies of chronological Q4 as compared to a 60-77% decrease for those of biological. Starting from quartile 2 biologically aged flies laid significantly higher number of eggs than flies of the same chronological quartile. Our results point out the significant difference in flies of the same biological and chronological quartile and raise the question about the suitability of comparison traits of organisms with different lifespans same chronological age.

zoology↗

Intergenerational metabolic priming by sperm piRNAs

SummaryPreconception parental environment can reproducibly program offspring phenotype without altering the DNA sequence, yet the mechanisms underpinning this epigenetic inheritance remains elusive. Here, we demonstrate the existence of an intact piRNA-pathway in mature Drosophila sperm and show that pathway modulation alters offspring gene transcription in a sequence-specific manner. We map a dynamic small RNA content in developing sperm and find that the mature sperm carry a highly distinct small RNA cargo. By biochemical pulldown, we identify a small RNA subset bound directly to piwi protein. And, we show that piRNA-pathway controlled sperm small RNAs are linked to target gene repression in offspring. Critically, we find that full piRNA-pathway dosage is necessary for the intergenerational metabolic and transcriptional reprogramming events triggered by high paternal dietary sugar. These data provide a direct link between regulation of endogenous mature sperm small RNAs and transcriptional programming of complementary sequences in offspring. Thus, we identify a novel mediator of paternal intergenerational epigenetic inheritance.

developmental biology↗

INSULIN-LIKE PEPTIDES REGULATE FEEDING PREFERENCE AND METABOLISM IN DROSOPHILA

Fruit flies have eight identified Drosophila insulin-like peptides (DILPs) involved in regulation of carbohydrate concentrations in hemolymph as well as accumulation of storage metabolites. In the present study, we investigated diet-dependent roles of DILPs encoded by genes dilp1-5, and dilp7 in regulation of insect appetite, food choice, accumulation of triglycerides, glycogen, glucose, and trehalose in fruit fly body and carbohydrates in hemolymph. We found that dilp2 gene predominantly influences body glycogen level, dilp3 - trehalose level in hemolymph, while dilp5 and dilp7 affect triglyceride level. Fruit fly appetite was found to be regulated by dilp3 and dilp7 genes. Our data contribute to the understanding of Drosophila as a model for further studies of metabolic diseases and may serve as a guide for uncovering the evolution of metabolic regulatory pathways.\n\nHIGHLIGHTSDifferent Drosophila insulin-like peptides play distinctive roles in metabolism, physiology and appetite regulation.\n\nLack of Dilp2 and Dilp5 abrogates glycogen accumulation on high carbohydrate diets\n\nLack of Dilp3 leads to build-up of trehalose in haemolymph on high-carbohydrate-low-protein diets\n\nLack of Dilp3 and Dilp7 leads to increased consumption of protein on low-carbohydrate-high-protein diets\n\nGRAPHICAL ABSTRACT O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

physiology↗