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Functional analysis of HSP complex expression in response to cold in \kur{Drosophila melanogaster}
ŠTĚTINA, Tomáš
The constitutively obsereved up-regulation of Hsp70 expression often led to premature conclusions about its critical role as a repair mechanism of cold injury that is, besides, expressed by protein misfolding/denaturation. In this study, we analyze the cold tolerance and the expression of 24 different mRNA transcripts of Hsp complex and other genes, that are associated with the repair of injury caused by cold. We use two strains of D. melanogaster: the wild type and the mutant type Hsp70- null, that lacks all 6 copies of the gene hsp70. We found out, that the larvae of two strains do not differ in their patterns of target genes expression during long term acclimation nor during recovery from chronic cold exposure and acute cold shock, therefore there is no transcriptional compensation of any other Hsp gene for the missing hsp70 in Hsp70- strain. The cold tolerance of Hsp70- strain larvae was impaired only, when they were exposed to strong acute cold shock by temperatures below -8°C. No difference in cold tolerance was observed, when the larvae were exposed to chronic cold exposure in 0°C or to mild acute cold shock by temperatures up to -4°C. Based on our results we assess, that the cold injury caused by strong acute cold schock is of another nature than caused by mild cold conditions and only in the first case Hsp70 expression is critical for the repair of cold injury in Drosophila melanogaster larvae.
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Current options for use of metabolomics in plant production
Maršík, Petr ; Vaněk, Tomáš
Metabolomics like other so-called "omics" approaches is based on the characterization and treatment as far as possible in the given dataset biological system. Meaning of each "omics" techniques lies mainly in their mutual integration which leads to the so-called. Systems biology linking output at the level of gene expression, protein translation and file metabolites with genomic data. These relationships are summarized in Fig. 1. The primary goal of systems biology is to understand the biological processes to such an extent that it is possible to predict the function of biological systems from the level of genes through metabolism, physiological processes to growth and development.
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Changes in the expression of selected testicular genes in mice
Valášková, Eliška ; Margaryan, Hasmik ; Žatecká, Eva ; Pěknicová, Jana
The decrease in population fertility has become a major concern in many developed countries. Recent studies show that infertility is affecting an estimated 15% of all couples (World Health Organization, WHO, 2010). Male infertility is the primary or contributing cause in 60% of cases. Male infertility is caused by a number of factors, such as genetic background, various environmental factors and disease. Diabetes mellitus (DM), a serious health problem on its own, is also suspected to be a contributing factor to male infertility. The aim of this project was to analyze the cellular, molecular and genetic effects of diabetic environment on spermatogenesis and sperm quality and to determine the impact of DM on the in vivo reproduction, using the mouse model (Mus musculus) inbred FVB. Diabetes was induced using streptozotocin. We used our knowledge and tools (unique monoclonal antibodies developed by our group) to determine the status of reproductive organs, anogenital distance, and the quality of sperms. Genetic analysis was performed by a quantitative Reverse Transcription Polymerase Chain Reaction (qPCR). We tested selected genes which are expressed in testicular tissue and thus can influence process of spermatogenesis and consequently the sperm quality. Our preliminary data strongly suggest that DM impairs male fertility. We have found significant changes in the body and reproductive organ weight of mice with DM. We have identified qualitative and quantitative changes in the expression of proteins in epididymal fluid and sperms. We have also detected an increased number of apoptotic cells in sperm of diabetic mice compared to the control group. To our knowledge, there is no study assessing the correlation between DM and “unexplained infertility”. In view of this, it is essential to analyze the effects of DM on male fertility, sperm quality, and reproduction parameters.
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Effect of exposure to bisphenol A on gene expression in the testicular tissue in male mice
Dorosh, Andriy ; Elzeinová, Fatima ; Žatecká, Eva ; Kubátová, Alena ; Pěknicová, Jana
Laboratory of Reproductive Biology, Institute of Biotechnology, Academy of Sciences of the Czech Republic, v.v.i., Prague, Czech Republic Bisphenol A (BPA) is a synthetic, endocrine-disrupting compound able to directly bind estrogen receptors. Free BPA has been detected in human samples indicating that humans are internally exposed to BPA. The purpose of this study was to analyse the effect of BPA on the male reproductive system and testicular gene expression in germ cells. We studied the influence of long-term low concentration BPA exposition on male fertility in vivo in a two-generation study in C57BL/6 mouse strain. In this work, BPA was added with water at two environmentally relevant concentrations: 0, 4 and 4 µg/l. We measured the reproductive organs weight and sperm cells morphology and quality. Expression of genes involved in endocrine regulation and energy metabolism in testis was analysed after BPA exposure. Next, the epigenetic mechanisms of gene expression and regulation during the germ cell differentiation and effect of BPA will be analysed.
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Gene expression reporters in \kur{Drosophila melanogaster}.
ŠTROS, Jiří
Drosophila melanogaster is a widely used model organism in genetic research and in a number of other disciplines associated with medical and biotechnological issues. The first part of this thesis presents a review of some basic genetic tools and gene expression reporters used in D. melanogaster research with emphasis on the use of GFP reporter. The second part presents a description and results of my experimental work aimed at the reporter construct consisting of adenosine deaminase gene (ADGF-A) and GFP marker. When using gene expression reporters such as GFP, it is important to know whether the presence of reporter does not affect the studied process. The experiment described in this study tested whether the fusion protein consisting of GFP and adenosine deaminase is fully functional enzyme or whether the enzyme activity is influenced by the presence of fluorescent tag. Results of this work support the usefulness of using the fusion construct as a gene expression reporter.
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The role of genetic background of the host on the pathogenesis of tick-borne encephalitis
PALUS, Martin
We examined the influence of the host genetic background on the pathogenesis of tick-borne encephalitis. We determined virus titers in organs and serum in different time intervals post-infection for different ways of inoculation. We also stated mean survival times and antibody production in different strains of mice infected with tick-borne encephalitis virus. Moreover, differences in expression of immunologicaly important genes in brains of infected mice were compared.
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