Background: Retroelements (REs) occupy a significant part of all eukaryotic genomes including humans. The majority of retroelements in the human genome are inactive and unable to retrotranspose. Dozens of active copies are repressed in most normal tissues by various cellular mechanisms.
View Article and Find Full Text PDFOne important question in aging research is how differences in genomics and transcriptomics determine the maximum lifespan in various species. Despite recent progress, much is still unclear on the topic, partly due to the lack of samples in nonmodel organisms and due to challenges in direct comparisons of transcriptomes from different species. The novel ranking-based method that we employ here is used to analyze gene expression in the gray whale and compare its de novo assembled transcriptome with that of other long- and short-lived mammals.
View Article and Find Full Text PDFBackground: Gray whale, Eschrichtius robustus (E. robustus), is a single member of the family Eschrichtiidae, which is considered to be the most primitive in the class Cetacea. Gray whale is often described as a "living fossil".
View Article and Find Full Text PDFBackground: Transcriptional changes that contribute to the organism's longevity and prevent the age-dependent decline of biological functions are not well understood. Here, we overexpressed pro-longevity gene encoding glutamate-cysteine ligase catalytic subunit (Gclc) and analyzed age-dependent changes in transcriptome that associated with the longevity, stress resistance, locomotor activity, circadian rhythmicity, and fertility.
Results: Here we reproduced the life extension effect of neuronal overexpression of the Gclc gene and investigated its influence on the age-depended dynamics of transcriptome and biological functions such as fecundity, spontaneous locomotor activity and circadian rhythmicity, as well as on the resistance to oxidative, proteotoxic and osmotic stresses.
Background: The molecular mechanisms that determine the organism's response to a variety of doses and modalities of stress factors are not well understood.
Results: We studied effects of ionizing radiation (144, 360 and 864 Gy), entomopathogenic fungus (10 and 100 CFU), starvation (16 h), and cold shock (+4, 0 and -4°C) on an organism's viability indicators (survival and locomotor activity) and transcriptome changes in the Drosophila melanogaster model. All stress factors but cold shock resulted in a decrease of lifespan proportional to the dose of treatment.
DNA double-strand breaks (DSBs) are involved in many cellular mechanisms, including replication, transcription, and genome rearrangements. The recent observation that hot spots of DSBs in human chromosomes delimit DNA domains that possess coordinately expressed genes suggests a strong relationship between the organization of transcription patterns and hot spots of DSBs. In this study, we performed mapping of hot spots of DSBs in a human 43-kb ribosomal DNA (rDNA) repeated unit.
View Article and Find Full Text PDFGeneral 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.
View Article and Find Full Text PDF