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Multidisciplinary characterization of interactions between oestrogen hormones and their receptors during sperm capacitation.
Bosáková, Tereza ; Komrsková, Kateřina (advisor) ; Smrček, Stanislav (referee) ; Postlerová, Pavla (referee)
This doctoral thesis was focused on the multidisciplinary characterizatrion of interactions between hormones and their receptors during sperm capacitation, which is the final step in sperm maturation in mammals and the key event to achieve egg fertilization. Three oestrogenic hormones (17β-estradiol (E2), 17α-estradiol (αE2), 17α-ethynylestradiol (EE2)), which are part of environmental pollution, were selected for the study. These hormones are called endocrine disruptors as they can cause disorders of the hormonal system in animals, thereby adversely affecting physiological processes, including reproduction. A new analytical HPLC-MS/MS method was developed for monitoring of concentration changes of oestrogens (E2, αE2 and EE2) during time-dependent capacitation of mouse and rat sperm in vitro. For individual oestrogens, the concentration dependences of free, unbound hormone on the capacitation time were measured for three concentrations of individual hormones (200, 20 and 2 μg/L). The obtained concentration data were converted into values of relative concentrations, which were subjected to kinetic analysis. Kinetic models were proposed for the interaction of individual hormones with sperm, which were described by a system of differential equations with optimization of rate constants and molar...
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Roles of sperm morphology variation on proteomic content in muroid rodents
Drozdová, Tereza ; Stopka, Pavel (advisor) ; Postlerová, Pavla (referee)
We can find a whole range of morphological differences between the spermatozoa of different animal species, whether at the level of shape, size or intracellular arrangement. It has been proven that these differences are likely to be driven by selective pressure caused by sperm competition. This can cause morphological adaptations that give sperm a selective advantage and increase the individual's success in fertilization. The main goal of my diploma thesis was to determine whether individual morphological variability of spermatozoa is detectable at the proteome level and possibly to determine what changes at the proteome level occur in spermatozoa with changing morphology. Three species of rodents, Mus musculus, Apodemus flavicollis and Microtus arvalis, were selected for this study, and a thorough morphometric measurement of their sperm was performed. Because the greatest variation was detected in the dimensions of the apical hook, only acrosomal proteins were analyzed by mass spectrometry, and then the proteins that distinguished the most sperm with long and short apical hooks were determined by discriminant analysis and machine learning methods. A significant trend among sperm-separating proteins with short and long apical hooks, regardless of species, has been identified for proteins involved...
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Rab-2A protein: its localization and function in human spermatozoa and fertilization
Sadílková, Lucie ; Postlerová, Pavla (advisor) ; Lánská, Eva (referee)
The Rab-2A protein belongs to the Rab family of monomeric G-proteins involved in the regulation of intracellular vesicular transport. Although several studies describing the role of Rab-2A protein in mammalian sperm have been published, the exact localization and function of this protein in male gametes have not been fully understood yet. In the diploma thesis, we were the first to describe the presence of Rab-2A in human sperm using 5C5, produced by the Laboratory of Reproductive Biology. Using the 5C5 antibody, we were able to identify several Rab-2A isoforms with molecular weights of 26, 24, 22, and 18 kDa in the human sperm lysate, confirmed by mass spectrometry analysis. Using the indirect immunofluorescence method, we localized Rab-2A in the acrosome area of both ejaculated and capacitated sperm. We noticed that Rab-2A leaves the sperm during the acrosomal exocytosis. We also found a reduced Rab-2A protein level in sperm of patients with various pathologies of ejaculate. Based on studies describing the role of Rab-2A in acrosome biogenesis and the presence of Rab-2A in bovine sperm perinuclear theca, we tried to detect Rab-2A in this protein layer in human sperm. However, the chosen method is apparently not applicable to human sperm and isolation has failed. Additionally, we demonstrated the...
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Study of sperm proteins in different mammalian species
Pohlová, Alžběta ; Postlerová, Pavla (advisor) ; Ryšlavá, Helena (referee)
Reproduction is an essential feature of all animals and a fundamental step to produce new generations. Study of sperm proteins is crucial for understanding of the sperm-egg recognition. We searched out sperm surface proteins involving in the zona pellucida (ZP) binding and studied whether these proteins are preserved throughout mammalian species. Indirect immunofluorescent technique was used to test a panel of monoclonal antibodies prepared against boar sperm surface proteins on spermatozoa of bull and mice. We found a cross-reactivity of some antibodies against boar sperm with bull ejaculated and mouse epididymal spermatozoa. Further, we isolated sperm proteins from different mammalian species, such as pig, bull, dog, cat, mouse and human. Proteins were separated by SDS- electrophoresis and protein/glycoprotein profiles from epididymal, ejaculated and in vitro capacitated sperm were compared. The interaction of sperm with ZP was studied on electrophoretically-separated sperm surface proteins from pig and bull with biotin-labeled ZP glycoproteins. Antibodies, which reacted with boar sperm surface proteins with ZP- binding activity, therefore could be potential egg-binding receptors, were used for monitoring of the sperm protein origin in reproductive fluids and tissues. (In Czech) Keywords: sperm...
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Isolation and study of proteins with zona pellucida binding activity
Zigo, Michal ; Postlerová, Pavla (advisor) ; Ryšlavá, Helena (referee) ; Antalíková, Jana (referee)
Binding of sperm to the oocyte is mediated by complementary molecules on the surface of both gametes and involves the interaction of sperm protein receptors with the zona pellucida (ZP) saccharide structures. It has been shown that many proteins receptors are involved in the sperm-ZP interaction, and potential primary sperm receptors for ZP glycoproteins have been investigated in various mammals. The majority of proteins with identified sperm-ZP binding activity belong to the plasma membrane proteins. However, the exact methods for isolation of sperm membrane proteins are still to be standardized. This study is focused on investigating how employment of various isolation protocols leads to acquisition of various protein mixtures. Further in the work, two possible approaches towards identification of potential ZP-binding partners are implemented, in order to disclose novel primary ZP-binding receptor candidates. Sperm proteins of ejaculated and in vitro capacitated boar sperms were isolated by: Triton X-100, Triton X-114, acetic acid, sodium dodecyl sulphate (SDS), N-octyl-β-D- glucopyranoside (OBG), rehydration buffer (RHB), and finally by freezing-thawing extraction and they were characterized by 1-D, 2-D protein profiles, glycoprotein staining and substrate zymographic methods. The results have...
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Secreted proteins by male reproductive tract
Cozlová, Nina ; Postlerová, Pavla (advisor) ; Železná, Blanka (referee) ; Antalíková, Jana (referee)
1 AbstractAbstractAbstractAbstract Proteins secreted in the male reproductive tract play a key role in post-testicular development of sperm and in further steps needed for fertilization. Sperm maturation represents a key step in the reproduction process. Sperm, during the passage through the epididymis undergoes significant changes due to proteolytic and glycolytic activities in the epididymal fluid. Inhibitor of acrosin protects spermatozoa and reproductive epithelium against proteolytic degradation and also protects binding sites for ZP on sperm plasma membrane. In boar reproductive system acrosin inhibitor (AI) was found in seminal plasma and on sperm plasma membrane. Polyclonal antibody recognized AI in extracts of the cauda epididymidis, seminal vesicles, prostate, and Cowper's glands. Using immunofluorescence method has revealed the AI in the epithelium and lumen of these organs but also on the surface of epididymal and ejaculated spermatozoa. We registered the increasing signal of AI from caput to cauda epididymis. Gene expression of AI mRNA was detected in the epididymis, seminal vesicles, prostate, and Cowper's glands and increased gradually throughout the epididymal duct. In present study, we also monitored AI in boar epididymal fluid and spermatozoa along the organ. In the epididymis, AI may...
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Use of transcriptomics to study mechanism of the action of complex mixtures of organic compounds occurring in the ambient air focusing on polycyclic aromatic hydrocarbons
Líbalová, Helena ; Topinka, Jan (advisor) ; Krásný, Libor (referee) ; Postlerová, Pavla (referee)
Polycyclic aromatic hydrocarbons (PAH) represent a large group of organic compounds occuring as pollutants in ambient air. Besides their genotoxic effect, some of them are known to be complete carcinogens and act via nongenotoxic and tumor promoting mechanism. Although effects of many individual compounds are well-documented, human exposure to polycyclic aromatic hydrocarbons in ambient air occurs through complex mixtures and only few studies describe the behavior of PAH in real complex mixtures. The first part of the thesis is dealing with the global gene expression changes in human embryonic lung fibroblasts (HEL) as a consequence of the effect of complex mixtures containing PAH extracted from the respirable airborne particles PM2.5. These particles were collected in 4 localities in the Czech republic (Ostrava - Bartovice, Ostrava - Poruba, Karviná, Třeboň) differing in the level of the air pollution. Gene expression changes induced by three subtoxic concentrations of organic extracts (EOM - extractable organic matter) from each locality after 24 hour incubation were examined by microarray analysis. Pathway analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database was applied to interpret gene expression data. In each locality we identified several deregulated signaling pathways...
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Isolation and characterisation of oviductal proteins involved in formation of sperm oviductal reservoir in cow
Kračmerová, Jana ; Liberda, Jiří (advisor) ; Postlerová, Pavla (referee)
The oviduct plays an important role in the complex process of fertilization and in the early phase of embryo development. Isolation and characterization of some components of bovine oviduct participating in the formation of oviductal sperm reservoir was a subject of the present study. Two affinity sorbents containing immobilized components of bull seminal plasma (non-separated proteins of bull seminal plasma and their phosphorylcholine binding fraction) were prepared and used for the study of interaction of immobilized ligands with components of oviductal epithelium. Two types of preparation of oviductal membrane proteins of the isthmus region were isolated: complete membrane proteins and the apical fraction of membrane proteins. These preparations were separated using prepared affinity matrices. in both cases only an insignificant amount of proteins was found in the adsorbed fractions. Further attention has been paid to the identification of four protein zones detected after electrophoretic separation in the presence of SDS (rel. mol. wt. 15 500 - 18 500) in the fraction of apical membrane proteins. These proteins were identified after the electrophoretic separation and tryptic digestion using MS analysis as bovine histones H4, H2A typ 2-C, H2B typ 1-K a H3.3. Proteins identified as bovine...
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