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Response of different genotypes of Zea mays L. and Vicia faba L. treated with brassinosteroids to water deficit
Kuklíková, Radka ; Rothová, Olga (advisor) ; Hnilička, František (referee)
This work monitors the response of plants to the application of a solution of synthetic brassinosteroid (5-fluor-3α,17β-dihydroxy-5α-pregnan-6-on) under drought stress conditions and subsequent restoration of water availability. The response of two plant species was monitored under six-day period of cessation of watering and under six-day period of renewed optimal water supply. The experiments were carried out on plants with different type of photosynthesis - C3 plant Vicia faba L. and C4 plant Zea mays L.. For both plant species, three varieties/genotypes were used. Photosynthetic, morphological and developmental characteristics were monitored. The brassinosteroid treatment influenced more the morphological than the photosynthetic characteristics. The content of photosynthetic pigments was influenced more than the chlorophyll fluorescence parameters. The differences in morphological characteristics between individual varieties/genotypes were observed. The response to the application of brassinosteroid was observed especially for drought-sensitive variety/genotype. Application of brassinosteroid caused increase of the dry mass of leaves and roots, the height to leaf , the height of the whole plant and its increment under stress and post-stress periods in both plant species. The content of...
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Characterization of the Hstx1 and Hstx2 hybrid sterility candidate genes
Kašíková, Lenka ; Jansa, Petr (advisor) ; Rothová, Olga (referee)
Speciation, the formation of new species, is an essential evolutionary process that causes species diversity on the Earth. At the beginning of this process is the separation of two populations by a reproductive barrier that prevents gene flow between these populations. One of the mechanisms, which enable reproductive isolation, is hybrid sterility (HS). It is a mechanism of postzygotic isolation that is described in a number of eukaryotes. The first discovered gene of hybrid sterility in vertebrates is the mice gene Hst1, later identified as gene Prdm9. By genetic and molecular analysis the locus on the X chromosome was determined, whose interaction with Prdm9 causes sterility or reduced fitness in male hybrids. This locus contains two genetic factors: Hstx1, causing an abnormal morphology of spermatozoa, and Hstx2, causing an arrest in spermatogenesis in pachytene spermatocytes and sterility. In my thesis I focus on the effect of deletion of a candidate hybrid sterility gene Fmr1nb on the X chromosome. The analysis of males B6N.Fmr1nbmut with deletion variants of the Fmr1nb gene showed that Fmr1nb is one of the factors influencing spermatogenesis. An increase in morphologic abnormalities in spermatozoa occurred in males with Fmr1nb gene deletion. This phenotype is identical with Hstx1. The effect...
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Organoids - the phenomenon of complex organ-like structures cultivation in vitro
Vilímková, Veronika ; Janečková, Lucie (advisor) ; Rothová, Olga (referee)
Pluripotent embryonal stem cells (ESCs) are unique for their ability to proliferate and differentiate into almost all cell types. In the presence of appropriate stimuli, they are able to initiate morphogenesis in vitro. Stem cells are able to differentiate into specific cell lines of a given tissue and to arrange three- dimensional (3D) structures. These so-called organoids are formed in a self-organizing process that mimics normal ESCs development. Organ development is a complex process that requires temporally and spatially ordered regulatory signals. 3D organization of these structures allows important cell-cell interactions. Organoid cultures are thus the area of a huge potential. Organoids are accessible to all standard experimental manipulations. They are therefore an ideal tool for the research of stem cells, signaling pathways, organogenesis and disease modeling. Finally, they may open up new avenues for regenerative medicine and gene therapy. Powered by TCPDF (www.tcpdf.org)
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Marfan syndrome, the main genetic causes
Šinknerová, Eliška ; Rothová, Olga (advisor) ; Daňková, Pavlína (referee)
This thesis is a review with the topic of Marfan syndrome (MFS) that hasn't been sufficiently described in Czech scientific literature yet. The first chapters pursue general informations and history of research of MFS, which was first desribed in 1896 and following research continued. During 1990s the main interest was to describe manifestations of Marfan syndrome and to find main genetic causes. Research continues until today and it is focused on searching specific mutations causing this syndrome. The thesis furthermore describes clinical manifestations classical MFS and neonatal MFS, e. g. manifestations in many body systems as sketal, cardiovascular, pulmonar and other systems. Thesis is focused on process which enables to diagnose MFS. The main part of the thesis is a desctiption of molecular nature and genetic aspects of this syndrome. The thesis describes in detail gene FBN1 and different types of mutationon which are responsible for formation of MFS. Attention is paid to genotype/phenotype correlation. This thesis also includes suggestions for work with this topic (MFS) in teaching at high schools and grammar schools.
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Formation of complex chromosomal rearrangements in cancer cells and significance of these events
Rochlová, Kristina ; Zemanová, Zuzana (advisor) ; Rothová, Olga (referee)
Chromoanagenesis is a catch-all term of recently described catastrophic events that generate complex karyotypes. These events are divided according to the characteristic features and are termed chromothripsis, chromoplexis and chromoanasynthesis. Chromothripsis represents a disintegration of chromosomes or their parts into hundreds of small fragments. Those chromosome fragments are then incorrectly reassembled. Chromoplexis rearrangements are not very different from chromothripsis rearrangements. The main difference is a lower number of breakpoints and the distribution of aberrations in the whole genome. The erroneous replication processes occur during chromoanasynthesis. There are several mechanisms responsible for breakdowns of a DNA molecule. In the case of chromothripsis, micronucleus formation is probably the most important mechanism. During chromoplexis, transcriptional stress plays a major role. Replication stress is associated with chromoanasynthesis rearrangements. The result of all these processes are highly rearranged chromosomes with numerous losses or gains of genetic material. This work summarizes the current knowledge of the mechanisms that are mentioned above and the genesis of complex aberrations. At the same time, it represents the connection between complex karyotype and clonal...
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Response of primary photosynthetic processes in C3 and C4 monocotyledonous plants to steroids aplication
Frimlová, Klára ; Rothová, Olga (advisor) ; Mocová, Klára Anna (referee)
Brassinosteroids and ecdysteroid are naturally occuring chemical compounds in plants. The aim of this study was to show whether the application of exogenous steroids such as brassinosteroids (24-epibrassinolide, 28-homobrassinolide, 24-epicastasterone) and ecdysteroid (20-hydroxyecdysone) can affect the morphological parameters and primary photosyntetic processes of selected monocotyledons that was barley, wheat, maize and sorghum. Non-destructive method for measuring of fast kinetics of chlorophyll fluorescence in investigated plants was used. Analysis of primary photosynthetic processes was realized in five time periods from the application of exogenous steroids on the two different old leaves. The response to the treatment by exogenous steroid was different species by plant species. One week after the application of exogenous steroids plants showed differences in their morphological parameters but most of them were not signifficant. The most steroid-sensitive plant was wheat morphological parameters of were significantly different from untreated control plants. No change in maximum quantum yield of photosystem II to the application of exogenous steroid in plants of Sorghum bicolor L. was detected. In the other examined plant species changes in photosynthesis parameters were detected which...
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X chromosome inactivation in human with abnormal gonosomal assembly
Chaloupková, Veronika ; Šolc, Roman (advisor) ; Rothová, Olga (referee)
X chromosome inactivation is the process of genetic regulation of mammals, which is designed to balance the genetic dose between male sex chromosomes (XY) and female sex chromosomes (XX). During embryonic development in females, one of the two X chromosome is inactivated and that it's detected in the cell as a Barr body. The other chromosome remains active. The whole process is controlled by genes from the X inactivation center. At the same time, we can see that some genes from the inactivated chromosome can escape and they continue in creating their products. That could be the cause of different phenotype of individuals with heterochromosome aneuploidy. This work summarized the current knowledge of the process and regulation of X chromosome inactivation in people with abnormal set of gonosomes and compates them to the inactivation process in healthy woman.
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Honey bee (Apis mellifera) virome
Kadlečková, Dominika ; Tachezy, Ruth (advisor) ; Rothová, Olga (referee)
Microbiome is composed of all microorganism (fungi, bacteria, archea, protozoa, virus) sharing the same space at the same time. Virome which consists of viruses either of the host or viruses of other microorganisms and of genetic elements derived from viruses, is part of the microbiome. Microbiome plays a role in a number of processes which are vital for development and survival of the host. Virome can affect host either directly or indirectly by interaction with other parts of microbiome. This thesis is focused on virome of Apis mellifera, globally managed pollinator. Viral diseases are one of the factors responsible for high colony losses of this pollinator and therefore this work is mostly dedicated to those viruses which were confirmed as pathogens of Apis mellifera. Also, their interaction with other pathogens of Apis mellifera, which leads to great losses of these pollinators will be discussed. Key words: virome, honey bee, Apis mellifera, honey bee viruses, colony losses
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