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Reproductive isolation between diploid and tetraploid cytotype of Vicia cracca and possibilities of evolution of this aggregate
Vlčková, Zuzana ; Münzbergová, Zuzana (advisor) ; Mráz, Patrik (referee)
Master thesis investigates reproductive barriers in diploid-polyploid complex of Vicia cracca. Complex with basic chromosome number x=7 consists of diploid (2x=14), tetraploid (4x=28) and rare triploid (3x=21) cytotype. I studied prereproductive barriers between diploid and tetraploid cytotype: phenology of flowering, pollinators' behavior (preference of spieces of pollinators to cytotypes, sequence of visited cytotypes), variables, that could explain pollinators' behavior (amount of nectar as the main reward, size and amount of pollen grains as a potentional reward). To find out how strong the triploid block is I analyzed ploidy of seeds and seedlings from mixed-ploidy population. The habitat isolation showed up to be the strongest reproductive barrier. Pollinator's behavior meaningfully contributes to isolation, phenology of flowering contributes only minimally. Index expressing rate of prereproductive barriers is 0,956. Pollinator Bombus pascuorum visited on one locality preferably tetraploid plants and Andrena sp. preferred diploid plants. Even though tetraploid plants produce more nectar, no other analysis showed pollinators' preference to tetraploid plants. I prepared one squash of diploid V. cracca using method of in situ hybridization. This method needs to be optimilized for the studied taxon.
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Earlier evolutionary dead-ends, now the creators of a reproductive strategy: the origin and reproduction of the all-male water frog lineage Pelophylax esculentus
Doležálková, Marie ; Choleva, Lukáš (advisor) ; Mikulíček, Peter (referee) ; Kratochvíl, Lukáš (referee)
Asexual modes of reproduction are usually based on the principle of copying (cloning) DNA from the female and passing it on to the offspring. For most asexually reproducing vertebrates the progeny develop from an unreduced and often unfertilised egg. This is driven by the mechanisms of parthenogenetic and gynogenetic reproduction. While in the former the clonal germ cell develops spontaneously and separately, in the latter a sexual partner is needed to activate the cleavage of the ovum, although without the fusion of the sperm and egg. Therefore in both cases there is no fertilization and the clonal progeny consist solely of daughters, hence the majority of previous studies have only focused on asexual female lineages. However, on rare occasions asexual clonal males can arise when the right fertilization occurs. Whilst these offspring are usually infertile, fertile diploid asexual males have been discovered in just three genera of hybrid origin in vertebrates. One of these unique cases is the European water frog complex of the genus Pelophylax, whose distribution includes the Czech Republic. In areas around the upper Odra River populations of hybrid males were recently discovered who form stable all-male lineages, similar to those formed by asexual females. The results of this study show that males produce...
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Earlier evolutionary dead-ends, now the creators of a reproductive strategy: the origin and reproduction of the all-male water frog lineage Pelophylax esculentus
Kaštánková, Marie
Asexual modes of reproduction are usually based on the principle of copying (cloning) DNA from the female and passing it on to the offspring. For most asexually reproducing vertebrates the progeny develop from an unreduced and often unfertilised egg. This is driven by the mechanisms of parthenogenetic and gynogenetic reproduction. While in the former the clonal germ cell develops spontaneously and separately, in the latter a sexual partner is needed to activate the cleavage of the ovum, although without the fusion of the sperm and egg. Therefore in both cases there is no fertilization and the clonal progeny consist solely of daughters, hence the majority of previous studies have only focused on asexual female lineages. However, on rare occasions asexual clonal males can arise when the right fertilization occurs. Whilst these offspring are usually infertile, fertile diploid asexual males have been discovered in just three genera of hybrid origin in vertebrates. One of these unique cases is the European water frog complex of the genus Pelophylax, whose distribution includes the Czech Republic. In areas around the upper Odra River populations of hybrid males were recently discovered who form stable all-male lineages, similar to those formed by asexual females. The results of this study show that males produce...
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Earlier evolutionary dead-ends, now the creators of a reproductive strategy: the origin and reproduction of the all-male water frog lineage Pelophylax esculentus
Kaštánková, Marie
Asexual modes of reproduction are usually based on the principle of copying (cloning) DNA from the female and passing it on to the offspring. For most asexually reproducing vertebrates the progeny develop from an unreduced and often unfertilised egg. This is driven by the mechanisms of parthenogenetic and gynogenetic reproduction. While in the former the clonal germ cell develops spontaneously and separately, in the latter a sexual partner is needed to activate the cleavage of the ovum, although without the fusion of the sperm and egg. Therefore in both cases there is no fertilization and the clonal progeny consist solely of daughters, hence the majority of previous studies have only focused on asexual female lineages. However, on rare occasions asexual clonal males can arise when the right fertilization occurs. Whilst these offspring are usually infertile, fertile diploid asexual males have been discovered in just three genera of hybrid origin in vertebrates. One of these unique cases is the European water frog complex of the genus Pelophylax, whose distribution includes the Czech Republic. In areas around the upper Odra River populations of hybrid males were recently discovered who form stable all-male lineages, similar to those formed by asexual females. The results of this study show that males produce...
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Reproductive isolation between diploid and tetraploid cytotype of Vicia cracca and possibilities of evolution of this aggregate
Vlčková, Zuzana ; Münzbergová, Zuzana (advisor) ; Mráz, Patrik (referee)
Master thesis investigates reproductive barriers in diploid-polyploid complex of Vicia cracca. Complex with basic chromosome number x=7 consists of diploid (2x=14), tetraploid (4x=28) and rare triploid (3x=21) cytotype. I studied prereproductive barriers between diploid and tetraploid cytotype: phenology of flowering, pollinators' behavior (preference of spieces of pollinators to cytotypes, sequence of visited cytotypes), variables, that could explain pollinators' behavior (amount of nectar as the main reward, size and amount of pollen grains as a potentional reward). To find out how strong the triploid block is I analyzed ploidy of seeds and seedlings from mixed-ploidy population. The habitat isolation showed up to be the strongest reproductive barrier. Pollinator's behavior meaningfully contributes to isolation, phenology of flowering contributes only minimally. Index expressing rate of prereproductive barriers is 0,956. Pollinator Bombus pascuorum visited on one locality preferably tetraploid plants and Andrena sp. preferred diploid plants. Even though tetraploid plants produce more nectar, no other analysis showed pollinators' preference to tetraploid plants. I prepared one squash of diploid V. cracca using method of in situ hybridization. This method needs to be optimilized for the studied taxon.
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Reproductive isolation between diploid and tetraploid cytotype of Vicia cracca and possibilities of evolution of this aggregate
Vlčková, Zuzana ; Münzbergová, Zuzana (advisor) ; Trávníček, Pavel (referee)
Master thesis investigates reproductive barriers in diploid-polyploid complex of Vicia cracca. Complex with basic chromosome number x=7 consists of diploid (2x=14), tetraploid (4x=28) and rare triploid (3x=21) cytotype. I studied prezygotic barriers between diploid and tetraploid cytotype: phenology of flowering, pollinators' behavior (preference of spieces of pollinators to cytotypes, sequence of visited cytotypes), variables, that could explain pollinators' behavior (amount of nectar as the main reward, size and amount of pollen grains as a potentional reward). To find out how strong the triploid block is, I analyzed ploidy of seeds and seedlings from mixed-ploidy population. The habitat isolation showed up to be the strongest reproductive barrier. Pollinator's behavior meaningfully contributes to isolation, phenology of flowering contributes only minimally. Index expressing rate of prereproductive barriers is 0,990. Pollinator Bombus pascuorum visited on one locality preferably tetraploid plants and Andrena sp. preferred diploid plants. Even though tetraploid plants produce more nectar, no other analysis showed pollinators' preference to tetraploid plants.
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Methods of Molecular Biology in Predictive Diagnostics of Her/neu in Stomach Cancer
Důra, Miroslav ; Staněk, Libor (advisor) ; Gemperle, Jakub (referee)
Stomach cancer is a malignant neoplastic disease, which is caused by malignant transformation of the gastric mucosal epithelium. Elderly patients are more frequently affected, the majority of the patients are males. Stomach cancer has some typical features like minor symptomatology and early metastasis founding. Nowadays, a mild decrease of incidence is registered. Treatment of stomach cancer depends on its location and stage. Because of its relative chemo- and radioresistance, surgical resection is the only one potentially curable method, although there is high number of recurrences. An amplification and overexpression of HER2 receptor is detected in approximately 10 - 20 % patients with stomach cancer. This overexpression correlates with worse prognosis of disease. Treatment with a monoclonal antibody named trastuzumab, Herceptin® could significantly elongate their life. Trastuzumab is now widely and successfully used for the treatment of female patients with breast carcinoma. Detection of HER2 amplification is there needed. Treatment with trastuzumab can be useful only when HER2 positivity of tumor is determined. This determination should be made by a reliable test with sufficient sensitivity and specificity. The aim of this work is to summarize the methods of molecular biology that are used in...
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Reproductive isolation between diploid and tetraploid cytotype of Vicia cracca and possibilities of evolution of this aggregate
Vlčková, Zuzana ; Münzbergová, Zuzana (advisor) ; Jersáková, Jana (referee)
Master thesis investigates reproductive barriers in diploid-polyploid complex of Vicia cracca. Complex with basic chromosome number x=7 consists of diploid (2x=14), tetraploid (4x=28) and rare triploid (3x=21) cytotype. I studied prereproducitve barriers between diploid and tetraploid cytotype: phenology of flowering, pollinators' behavior (preference of species of pollinators to cytotypes, sequence of visited cytotypes), variables, that could explain pollinators' behavior (amount of nectar as the main reward, size and amount of pollen grains as a potentional reward). To find out how strong the triploid block is I analyzed ploidy of seeds and seedlings from mixed-ploidy population. The habitat isolation showed up to be the strongest reproductive barrier. Pollinator's behavior meaningfully contributes to isolation, phenology of flowering contributes only minimally. Index expressing rate of prereproctive barriers is 0,956. Pollinator Bombus pascuorum visited on one locality preferably tetraploid plants and Andrena sp. preferred diploid plants. Even though tetraploid plants produce more nectar, no other analysis showed pollinators' preference to tetraploid plants. I prepared one squash of diploid V. cracca using method of in situ hybridization. This method needs to be optimilized for studied taxon.
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Use of In Situ Hybridization to study evolution in plants
Vlčková, Zuzana ; Münzbergová, Zuzana (advisor) ; Šurinová, Mária (referee)
The main focus of this thesis is in situ hybridization method and its impacts in modern cytology. The first chapter of the thesis describes the method itself and its types, defines and enumerates fundamental terms of the method, describes the steps of preparation and actual experiments in detail and explains the process of evaluation and interpretation of results. Following chapter describes several cases studies on plants performed using ISH. It describes use of ISH to recognize introgression lines among hybrids and to determine their fertility, to study polyploids and evolution of the nonaploids and to study repetitive sequences in telomeres of lily plants. In the next chapter the thesis describes Vicia cracca agg. from morphological but mainly systematical point of view. The thesis is concluded by suggestion of possible utilization of genomic in situ hybridisation in order to reveal the pregenitors of tetraploid V. cracca and the evolution within the aggregate.
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Localization of individual opioid receptor subtypes in CNS
Lišháková, Michaela ; Hejnová, Lucie (advisor) ; Bendová, Zdeňka (referee)
In last decades, the research focused on opioid receptors has been intensively conducted in order to determine their role in various homeostatic functions, control of movement, neurotransmission and drug addiction. An important factor determining the pharmacologic role of opioid receptors is their distribution within the brain regions as well as at the cellular level. Over the past 40 years, a great deal of information concerning their distribution in the central nervous system has been collected, allowing us to determine their localization and mechanisms of their action. In general, results obtained from previous studies are in agreement. However, there are some inconsistencies that impede the accurate determination of receptor distribution and need to be clarified. This paper aims to summarize results of the previously published studies observing the localization of opioid receptors in the rat CNS. Emphasis is placed on the comparison of results obtained by all available methods.
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