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Development and differentiation of different types of yeast colonies: Regulation of metabolic diversification and development of cells with novel properties
Maršíková, Jana
Yeasts are unicellular organisms, but on a solid substrate they are capable of forming complex organized structures that behave like primitive multicellular organisms. Examples of these structures include colonies and biofilms, whose cells interact with each other, coordinate their growth and development, differentiate spatially and form specialized cell subpopulations in which specific processes and regulatory pathways occur. The basis of cellular differentiation and specialization is the formation of gradients of nutrients, metabolites and signaling molecules. Thus, multicellular yeast communities differ significantly from planktonic populations in their characteristics. The aim of this work is to increase knowledge related to the development and differentiation of both smooth and structured colonies of the yeast Saccharomyces cerevisiae. The literature introduction of the thesis provides an overview of the current knowledge on the development of yeast colonies and biofilms, especially of S. cerevisiae species, and also includes selected regulations important for the formation of multicellular populations. The thesis provides insights into the antagonistic function of the transcriptional regulators Cyc8p and Tup1p in the development of structured biofilm colonies. Genome-wide transcriptomic...
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Development and differentiation of different types of yeast colonies: Regulation of metabolic diversification and development of cells with novel properties
Maršíková, Jana ; Palková, Zdena (advisor) ; Heidingsfeld, Olga (referee) ; Demnerová, Kateřina (referee)
Yeasts are unicellular organisms, but on a solid substrate they are capable of forming complex organized structures that behave like primitive multicellular organisms. Examples of these structures include colonies and biofilms, whose cells interact with each other, coordinate their growth and development, differentiate spatially and form specialized cell subpopulations in which specific processes and regulatory pathways occur. The basis of cellular differentiation and specialization is the formation of gradients of nutrients, metabolites and signaling molecules. Thus, multicellular yeast communities differ significantly from planktonic populations in their characteristics. The aim of this work is to increase knowledge related to the development and differentiation of both smooth and structured colonies of the yeast Saccharomyces cerevisiae. The literature introduction of the thesis provides an overview of the current knowledge on the development of yeast colonies and biofilms, especially of S. cerevisiae species, and also includes selected regulations important for the formation of multicellular populations. The thesis provides insights into the antagonistic function of the transcriptional regulators Cyc8p and Tup1p in the development of structured biofilm colonies. Genome-wide transcriptomic...
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Differentiation of yeast colonies: The role of selected transcription factors and metabolic proteins
Plocek, Vítězslav
5 Abstract Although yeasts are unicellular microorganisms, they form complex multicellular formations such as biofilms and colonies under natural conditions. Within these structures, processes such as cell differentiation, specialization by particular cell populations and cell signalling, which are typical of multicellular organisms, take place. The literature introduction to this thesis summarizes current knowledge regarding the development of biofilms and colonies, in particular those of the model organism, Saccharomyces cerevisiae, and some selected regulations that are important for the formation of multicellular structures. In the results section, I focus on two lines of research. The first is directed towards mechanisms, involved in the formation of multicellular structures. In studying the formation of SLI biofilms (biofilms at the solid/liquid interface), we have documented the antagonistic role of the regulators CYC8 and TUP1 in their formation and have also described the effect of the presence of glucose on the development and stability of SLI biofilms of strain BR-F. During this study we[D1] have developed an imaging method that allows us to prepare and observe the internal structure (vertical cross-section) of SLI biofilms, as well as the growth of unattached cells, under physiological...
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Differentiation of yeast colonies: The role of selected transcription factors and metabolic proteins
Plocek, Vítězslav ; Palková, Zdena (advisor) ; Heidingsfeld, Olga (referee) ; Sychrová, Hana (referee)
5 Abstract Although yeasts are unicellular microorganisms, they form complex multicellular formations such as biofilms and colonies under natural conditions. Within these structures, processes such as cell differentiation, specialization by particular cell populations and cell signalling, which are typical of multicellular organisms, take place. The literature introduction to this thesis summarizes current knowledge regarding the development of biofilms and colonies, in particular those of the model organism, Saccharomyces cerevisiae, and some selected regulations that are important for the formation of multicellular structures. In the results section, I focus on two lines of research. The first is directed towards mechanisms, involved in the formation of multicellular structures. In studying the formation of SLI biofilms (biofilms at the solid/liquid interface), we have documented the antagonistic role of the regulators CYC8 and TUP1 in their formation and have also described the effect of the presence of glucose on the development and stability of SLI biofilms of strain BR-F. During this study we[D1] have developed an imaging method that allows us to prepare and observe the internal structure (vertical cross-section) of SLI biofilms, as well as the growth of unattached cells, under physiological...
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The development of swine B cells and the role of gama delta T lymphocytes in immunization of naive immune system.
Štěpánová, Kateřina
Thesis summary The process of B cell lymphogenesis in swine remains uncertain. Some reports indicate that pigs belong to a group of animal that use ileal Peyers's patches (IPP) for the generation of B cells while others point to the possibility that the bone marrow is functional throughout life. The functional subpopulations of B cells in swine are also unknown. Together with other ruminants, and also birds, γδ T cells in swine may account for >70% of all T cells which is in apparent contrast with humans and mice. The purpose of this thesis was to address these discrepancies and unresolved issues. The results disprove the existing paradigm that the IPP is primary lymphoid tissue and that B cells develop in IPP in an antigen-independent manner. On the other hand, it shows that bone marrow is fully capable of B cell lymphogenesis and remains active at least for the same period of time as it had been speculated for the IPP. This thesis also identified functionally different subsets of porcine peripheral B cells, and shows that CD21 molecules can be expressed in differential forms. Finally, this thesis identifies two lineages of γδ T cells that differ in many functional and phenotype features. This finding may explain why γδ T cells constitute of minority of lymphocytes in circulation of humans and mice.
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Evaluation of influence of mechanical loading on differentiation of stem cells into smooth muscle cells
Pražák, Šimon ; Filová, Elena (advisor) ; Maxová, Hana (referee)
Cultivation of cells in bioreactors with mechanical load simulates the physiological conditions to which cells in the body are exposed. This technology has been used to induce the differentiation of stem cells from adipose tissue towards the phenotype of vascular smooth muscle cells, which can further serve to form vascular replacements. At present, there is no established strategy for cultivating stem cells while being exposed to mechanical stress. The main aim of this work was therefore to optimize the cultivation strategy and determine the ideal load parameters. Differentiation was analyzed by immunofluorescence of specific smooth muscle cell markers, α-actin and h1-calponin, which were quantified by Western blot. Extracellular matrix production was also detected by immunofluorescence staining. The outcome of this work is the establishment of ideal conditions of cell culture in a bioreactor with mechanical load, during which they differentiate into smooth muscle cells. Three types of scaffolds were used for cultivation; plasma treated glass, fibrin-coated glass and decelularized pericardium. Preliminary results show that smooth muscle differentiation was succesfully induced in human and porcine adipose tissue stem cells. Cells were analyzed after 3 and 7 days of culture. Developing a stem cell...
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Phenotypic switching and cell differentiation in yeast Cryptococcus neoformans
Bauer, Martin ; Kuthan, Martin (advisor) ; Abrhámová, Kateřina (referee)
Cryptococcus neoformans is an opportunistic pathogenic yeast causing around 600 000 deaths annually. Its ability to cause a chronic infection is given by the emergence of different morfotypes. These morphotypes differ in cell structures and mechanisms (virulence factors) which have an influence on the resistance to stress factors encountered in the host. This work first describes molecular mechanisms of formation of these virulence factors. Next, it presents morphotypes occurring during infection and the hypovirulent pseudohyphal morphotype. However, this morphotype is interesting because of a modification in the signalisation leading to its manifestation. Finally, described signalling pathways present possible ways of regulating the virulence factors, and so the manifestation of different morphotypes. Understanding these signalling pathways could ultimately lead to improving the development of new drugs, given that Cryptococcus neoformans is highly resistant to the existing ones. Keywords: Cryptococcus neoformans, phenotypic switching, titan cells, cell differentiation, virulence, Vad1, Rim101, Usv101, RAM
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Androgenesis
Kočová, Helena ; Honys, David (advisor) ; Kocábek, Tomáš (referee)
(anglicky) Androgenesis in the plant kingdom is an interesting phenomenon, in which a new individual is regenerated from male gametophyte. Having gametophytic, i.e. haploid number of chromosomes, these plants are potentially useful in research as well as for the generation of new genotypes. Duplication of their genetic information then results in fully homozygous plants, that can be used for breeding. At the same time, microspores represent a unique system for studying totipotency, cell proliferation, differentiation and embryogenesis. However, in many important crops as well as in some model species, such technology has not yet been efficiently managed. The aim of this thesis is to summarize the knowledge about androgenesis, from the historical context to the latest discoveries, including methods, development, complications and at the end also the possible use of obtained doubled haploid plants. Keywords: androgenesis, male gametophyte, microspore embryogenesis, pollen, totipotency, cell differentiation, stress, organogenesis, haploid
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The development of swine B cells and the role of gama delta T lymphocytes in immunization of naive immune system.
Štěpánová, Kateřina
Thesis summary The process of B cell lymphogenesis in swine remains uncertain. Some reports indicate that pigs belong to a group of animal that use ileal Peyers's patches (IPP) for the generation of B cells while others point to the possibility that the bone marrow is functional throughout life. The functional subpopulations of B cells in swine are also unknown. Together with other ruminants, and also birds, γδ T cells in swine may account for >70% of all T cells which is in apparent contrast with humans and mice. The purpose of this thesis was to address these discrepancies and unresolved issues. The results disprove the existing paradigm that the IPP is primary lymphoid tissue and that B cells develop in IPP in an antigen-independent manner. On the other hand, it shows that bone marrow is fully capable of B cell lymphogenesis and remains active at least for the same period of time as it had been speculated for the IPP. This thesis also identified functionally different subsets of porcine peripheral B cells, and shows that CD21 molecules can be expressed in differential forms. Finally, this thesis identifies two lineages of γδ T cells that differ in many functional and phenotype features. This finding may explain why γδ T cells constitute of minority of lymphocytes in circulation of humans and mice.
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The development of swine B cells and the role of gama delta T lymphocytes in immunization of naive immune system.
Štěpánová, Kateřina ; Šinkora, Marek (advisor) ; Macela, Aleš (referee) ; Faldyna, Martin (referee)
Thesis summary The process of B cell lymphogenesis in swine remains uncertain. Some reports indicate that pigs belong to a group of animal that use ileal Peyers's patches (IPP) for the generation of B cells while others point to the possibility that the bone marrow is functional throughout life. The functional subpopulations of B cells in swine are also unknown. Together with other ruminants, and also birds, γδ T cells in swine may account for >70% of all T cells which is in apparent contrast with humans and mice. The purpose of this thesis was to address these discrepancies and unresolved issues. The results disprove the existing paradigm that the IPP is primary lymphoid tissue and that B cells develop in IPP in an antigen-independent manner. On the other hand, it shows that bone marrow is fully capable of B cell lymphogenesis and remains active at least for the same period of time as it had been speculated for the IPP. This thesis also identified functionally different subsets of porcine peripheral B cells, and shows that CD21 molecules can be expressed in differential forms. Finally, this thesis identifies two lineages of γδ T cells that differ in many functional and phenotype features. This finding may explain why γδ T cells constitute of minority of lymphocytes in circulation of humans and mice.
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