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Rab proteins in sperm life
Vojtová, Kristýna ; Páleníková, Veronika (advisor) ; Zelenková, Natálie (referee)
Rab proteins are the largest group of small GTPases. They work as key regulators in the intracellular vesicular transport of cells. This bachelor's thesis contains a literature review of current information on the function of Rab proteins in mammalian spermatozoa. The first part of the work is devoted to their structure, function, cycle, and diseases related to the dysfunction of Rab proteins. The second part is focused on sperm development and maturation linked with specific Rab proteins involved in individual steps during the life of the sperm. Rab proteins are important in cytoskeletal organization and cytokinesis of sperm during spermatogenesis. They participate in the acrosome biogenesis mediated by the Golgi apparatus and the morphological changes of sperm during spermiogenesis. They also play a key role in the acrosome reaction and interaction with the zona pellucida. Due to their necessity in the sperm development and maturation, Rab proteins are proposed as a marker of male fertility, which is summarized in the last part of the thesis. Keywords Rab proteins, GTPases, sperm, spermatogenesis, spermiogenesis, fertilization, infertility
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Molecular basis of the sperm selection in the mammalian female reproductive tract
Šrámková, Adéla ; Krylov, Vladimír (advisor) ; Postlerová, Pavla (referee)
Internal fertilization is typical for all mammals. The male transfers sperm cells into the female reproductive tract, where usually one of them reach the oocyte and fertilize it. The female reproductive tract must be adapted to provide a suitable environment for the sperm cells to survive until fertilization. On the other hand, it must also be able to select developmentally competent sperm cells and prevent others to get into the close contact with the oocyte. Physical and molecular mutual communication of sperm cells with the female reproductive tract is ensured by sperm surface molecules and the receptors of the female epithelia lining. It appears that these interactions are required for key transformations, both on the sperm surface and in the cells of the female reproductive tract, where gene expression is affected. As a result of these changes, the most suitable sperm cell with all the required characteristics is allowed to fertilize the matured oocyte.
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Aggregation of bull seminal plasma protein
Boháček, Hanuš ; Liberda, Jiří (advisor) ; Hýsková, Veronika (referee)
Mammalian fertilization is a sequence of unique and fascinating events, during which seminal proteins are of crucial role. In case of bull (Bos taurus), proteins of seminal plasma (BSP), especially its major component PDC-109, are known to be in aggregated forms, but little is known about mechanism of forming aggregates and their biological function. In present thesis we discovered some interesting properties of PDC-109 and BSP proteins. We found that concentration of these proteins influences their aggregation state significantly, which can be of great biological importance. Separation of seminal proteins by size exclusion chromatography revealed three main fractions denoted I, II and III, with apparent molecular weights of Mr > 150 000, Mr = 30 000 and Mr = 13 000, respectively. In case of PDC-109, molecular weights of theese fractions were retained even after purification procedure, which implies very stable interactions in forming of aggregates. In addition, there was a difference in distribution of PDC-109 glycoforms among fractions, which can be related to the fact, that theese fractions have different sperm membrane binding patterns as we determined by fluorescence microscopy. However, further experiments are needed for better understanding this issue.
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Sperm morphology and molecular mechanism associated with sperm fertilizing ability in mice.
Šebková, Nataša ; Hortová, Kateřina (advisor) ; Jonáková, Věra (referee) ; Linhart, Otomar (referee)
The process of sperm capacitation and acrosome reaction (AR) are highly dynamic processes essential for the fertilization, including cytoskeleton proteins in the sperm head. The study of the distribution of actin, spectrin and α-tubulin in the head of representative mammalian sperm indicates that before and after the AR there were changes in the distribution of the cytoskeleton structures in the sperm head of all representatives, mainly in the apical part of the acrosome, but also in the equatorial and postacrosome part of the sperm head. The particularly well-studied actin cytoskeleton plays an important role during the capacitation and before and after the AR. Environmental estrogens can interfere with the function of endogenous hormones in very low concentrations. They can interact with specific receptors affecting several signalling pathways leading to sperm capacitation and AR. The effect of 17β-estradiol, estrone, estriol and synthetic 17α-ethynylestradiol was evaluated by the ratio of tyrosine phosphorylation and the state of the acrosome during in vitro capacitation in the sperm head. This study has provided the evidence that estrogens significantly stimulate capacitation progress in a concentration-dependent manner. Estrogens decrease number of sperm after the induced AR too. The raising...
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Aggregation of bull seminal plasma protein
Boháček, Hanuš ; Liberda, Jiří (advisor) ; Hýsková, Veronika (referee)
Mammalian fertilization is a sequence of unique and fascinating events, during which seminal proteins are of crucial role. In case of bull (Bos taurus), proteins of seminal plasma (BSP), especially its major component PDC-109, are known to be in aggregated forms, but little is known about mechanism of forming aggregates and their biological function. In present thesis we discovered some interesting properties of PDC-109 and BSP proteins. We found that concentration of these proteins influences their aggregation state significantly, which can be of great biological importance. Separation of seminal proteins by size exclusion chromatography revealed three main fractions denoted I, II and III, with apparent molecular weights of Mr > 150 000, Mr = 30 000 and Mr = 13 000, respectively. In case of PDC-109, molecular weights of theese fractions were retained even after purification procedure, which implies very stable interactions in forming of aggregates. In addition, there was a difference in distribution of PDC-109 glycoforms among fractions, which can be related to the fact, that theese fractions have different sperm membrane binding patterns as we determined by fluorescence microscopy. However, further experiments are needed for better understanding this issue.
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Functional analysis of sperm quality after endocrine disruptor treatment
Linhartová, Zuzana ; Liberda, Jiří (advisor) ; Ryšlavá, Helena (referee)
The aim The aim of my study was to determine whether the selected endocrine disruptors (EDs) affect reproductive parameters of sperm. Due to two experimental models, in which was tested the influence of selected Eds, my work is divided into two parts: A) On the boar model (Sus scrofa) was tested effect of selected EDs (zearalenone (ZEN), di(2-ethylhexyl) phthalate (DEHP), vinclozolin (VIN) on the course of capacitation, acrosome responses in vitro and changes in the detection and localization of selected proteins. B) On the fish model (Perca fluviatilis L.) was tested the influence of the selected ED- bisphenol A (BPA) on the motility and velocity of fish sperm movement. Results Mammalian model In mammalian model the course of capacitation and acrosome reaction was significantly influencing by the examined EDs in comparision with control samples. The increase of the number of marked cells during capacitation and reduce of the number of marked cells after AR compared with the differences between experimental and control samples was confirmed by the flow cytometry method. At higher concentrations EDs clearly inhibited acrosome response and thus reduce the number of sperm capable of fertilization. The relevancy of the results of detection acrosome reaction was confirmed by using various methodological...
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Some factors influencing success of IVF-embryo transfer
Pertoldová, Stanislava ; Rajmon, Radko (advisor) ; Marie, Marie (referee)
Assisted reproduction is a field of medicine that deals with infertility tretment.
Ongoing improvements of laboratory technology as well as ongoing evolving scientific research within IVF research,including experimental embryology in routine practice is contributing in a steady improvement of success rates of assisted reproduction.
This thesis is primarily based on data and information provided by the laboratory of assisted reproduction of GEST IVF Ltd.clinic in Prague,which was collected during the year 2015. This data was analyzed and investigated to verify the effect of selected factors on the success of the treatment. In This thesis we have not used any personal data of patients in accordance with the legislation act.296/2008Sb.
The results show clear evidence between the treatment success rate and patients age within all evaluated parameters. The fundametal hypothesis of interdependence of embryo quality on the further development of the embryo after the transfer was comfirmed.
Conversely, the timeframe for embryo cultivation is not an important parameter of success. Commonly used cuture media also did not show a significant impact on treatment outcome.
Statistical calculations also confirmed surprisingly significant differences in embryo transfer after 72 hours development and 120 hours development for women ever 35 years. Transfers of younger embryos appears to be more convenient for women over 35 years.
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