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Molecular physiology of opioid receptors
Valný, Martin ; Novotný, Jiří (advisor) ; Hejnová, Lucie (referee)
The opioid receptors (OR) belong to the family of G protein-coupled receptors (GPCRs). ORs mediate the effects of the opioids, leading primarily to inhibition of neuroexcitability, predominantly through the class of the inhibitory G proteins Gi/Go. Cloning of ORs confirmed the existence of four subtypes of ORs, which mediate effects of different classes of opioid ligands. The major aim of this work is to summarize the current knowledge about characteristics and function of ORs at the molecular level. Acute exposition of ORs to their agonists results in activation of the signaling cascades that trigger mechanisms leading to analgesia. Chronic exposition of ORs to their agonists leads to desensitization and internalization of the receptors and induces adaptive changes in signal transduction system that suppresses the opioid action, and may result in the development of opioid tolerance and dependence. Although a big progress has been made in the field of understanding the molecular mechanisms of the OR-mediated signaling, there are still a lot of unresolved questions that are necessary to answer.
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Efekt inhibice proteasomu na proteom Arabidopsis thaliana
Dufek, Martin
Proteasome is highly conserved in its structure among all eukaryotes. The main function of this multi-protein complex is to facilitate protein turnover and degrade misfolded, altered, aged or unneeded proteins. Proteasome-dependant degradation predominantly operates in cooperation with a complex system that conjugates proteins destined for degradation to ubiquitin. Emerging evidence suggests that the proteasome-dependant degradation is crucially involved in plant hormone signalling and as such could play a central role in plant growth and development. This bachelor thesis entitled "Effects of proteasome inhibition on Arabidopsis thaliana proteome" reviews proteasome-ubiquitin pathway with the focus on plant hormone signalling. In the experimental part, the effects of proteasome inhibition were investigated via LC-MS profiling. Altogether, abundances of more than 1400 proteins were followed. PCA analysis and a detailed pair-wise comparison of MG-132 and mock treated seedlings provided an insight into the molecular mechanism behind processes in the response to proteasome inhibition.
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Investigation of the molecular mechanisms of elimination of clinically relevant tumors by killer cells of the immune system.
Libigerová, Martina ; Bosáková, Zuzana (referee) ; Bezouška, Karel (advisor)
Carbohydrates have an essentials role in wide range of biological phenomena. It is well known that most of the eukaryotic proteins are glycosylated and that their glycosylation undergoes dynamic changes, nevertheless the biological imperative for these modifications is still not fully understood. However, one area in which the importace of cell surface glycosylation has recently been the subject of active investigations is the tumor plasma membrane biology, where many changes in glycosylation have been found useful for diagnosis, and mostly recent, even for the therapies of malignant disease. Interestingly cell surface glycoconjugates, namely N-linked and O-linked oligosaccharides have been found therapeutically attractive for treatment of certain tumors. And although our understanding of the participation of these principal glycan classes in tumorigenesis is far from complete, there are already several examples of carbohydrate-based antitumor vaccines. Therefore, we decided to give this issue more attention, especially the molecular mechanisms responsible for identifying changes in glycosylation of the surface of tumor cells of the immune system. Although in the past in our laboratory identified a receptor-type lectin specific lectin receptors on natural killer cells, very little is yet known...
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Diagnostics of species complex in the family Adelgidae by molecular markers
JAROŠOVÁ, Andrea
Three molecular markers were tested for use in species identification of two selected genuses of the Adelgidae. Two mitochondrial markers were successfully amplified and sequenced, part of the COI gene and fragment between the COII and COIII genes. Their ability to distinguish species complexes was checked by statistical methods and by construction of phylogenetic trees.
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Utilization of molecular markers in oil seed rape breeding programmes
KRISTINOVÁ, Helena
Current breeding of oilseed rape is focused on breeding of F1 hybrids and the male sterility and self-incompatibility could play the significant role in hybrid breeding programmes. Plant breeders also more widely utilize molecular genetic techniques for selection of desirable plants/genotypes. Molecular methods are faster, more reliable and more specific than conventional ones, which are based mainly on morphological descriptors. The aim of my thesis was to optimize PCR analysis methods and to develop specific molecular markers for target plant selection in oilseed rape hybrid breeding programmes. The new marker for detection of fertility restoration gene (Rf) in CMS Ogu-INRA plants was tested. New primer pair RsPPRF2/RsPPRR2 was designed in the coding region of PPR-B protein, which participates in the restoration of fertility in CMS Ogu-INRA. Also newly designed primers BrSLGIIF/BrSLGIIR were tested in SI plants. The optimal annealing temperaturse of these primers was 58 °C. But amplification in some SC plants was also observed. The optimization of the PCR reaction was performed for all designed primers. The set of F1 SI hybrids created by crossing of two lines with different S II haplotypes was tested by using of the PCR-RFLP technique for detection of polymorphism in amplified fragments.
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Could fur characters be a source of phylogenetic information?
VOLDŘICHOVÁ, Marie
This work analysed phylogenetic utility of several characters associated with basic coloration, moulting and whorls in Cervidae via comparison of these traits with relatively robust phylogeny of this group based on several morphological, ethological and molecular data. I was able to detect probable evolutionary history of some selected traits, their ancestral state and synapomorphies of recognized clades.
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Cluster studies in molecular beams
Profant, Václav ; Kužel, Petr (referee) ; Dian, Juraj (advisor)
In the present work we study properties of clusters of small heteroatomic molecules with biological relevance by several experimental methods based on molecular beams. In the rst experiment structure and dynamics of size-selected charged pyrrole clusters have been studied by means of molecular beam scattering experiment. Small neutral P yn clusters were produced in Py/He expansions and larger mixed P ynArm clusters in Py/Ar expansions, and the scattering experiment with a secondary beam of He atoms was used to select the neutral clusters of dierent sizes. The complete size-selected fragmentation patterns for the neutral dimer to tetramer after an electron impact ionization at 70 eV from the measurements of the angular and velocity distributions at dierent fragment masses. In second experiment photolysis of size selected pyrrole, imidazole and pyrazole clusters has been investigated. Comparison with the photolysis of an isolated molecules and between studied systems has been made. Clusters were photolyzed at 243 and 193 nm and the kinetic energy distributions of the H-photofragments have been measured and analyzed. Finally the mass spectra of the fragments after multiphoton ionization have been measured. The signicant inuence of the cluster environment to the photolytic behavior was observed and discussed.
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