|
|
delta subunit of bacterial RNA pol and its role in regulation of gene expression in B. subtilis
Dvořáček, Lukáš ; Krásný, Libor (advisor) ; Vopálenský, Václav (referee)
Delta subunit of bacterial RNA pol and its role in regulation of gene expression in B. subtilis. In this work I focus on regulation of eubacterial gene expression. First, I describe recent knowledge about a key stage of gene expression - transcription, focusing on regulation of trancription iniciation via small effector molecules (guanosine tetraphosphate, initiating nucleoside triphosphate) that are important for the regulation of ribosomal RNA. Second, in the experimental part of my work, I focus on the role of the _ protein, a subunit of RNA polymarase in gram positive bacteria, in transcription iniciation and its effects on regulation of RNA polymerase by the concentration of initiating nucleoside triphosphates.
|
|
|
Analysis of karyotype and sex chromosome differentiation in African annual killifish of the genus Nothobranchius (Teleostei: Nothobranchiidae)
Lukšíková, Karolína ; Sember, Alexandr (advisor) ; Zrzavá, Magda (referee)
Teleost fishes (Teleostei) encompass more than half of the extant vertebrate biodiversity. Their genomes display considerable plasticity and flexibility, going hand in hand with polyploidization events and repetitive DNA dynamics. Teleosts also display a striking diversity in mechanisms of sex determination and differentiation. The aim of the present thesis was to study the mechanisms underlying the karyotype and sex chromosome differentiation through cytogenetic mapping of repetitive DNA (by fluorescence in situ hybridization, FISH) in selected representatives of the African annual killifishes of the genus Nothobranchius (Teleostei: Nothobranchiidae). Nothobranchius spp. evolved a unique adaptation to freshwater temporary water pools whose existence is limited to periods of rainy season in African savannahs. Recent diversification, allopatric speciation in non-overlapping generations and small-sized populations together with known cytogenetics collectively suggest fast dynamics of chromosomal changes in Nothobranchius killifishes. The study took advantage of the availability of i) more populations of several closely related species for analysis and ii) data on specific repetitive DNA composition in selected Nothobranchius genomes as revealed by RepeatExplorer analysis. My work showed considerable...
|
|
| |
|
|
Cytogenetics of selected groups of ray-finned fishes (Actinopterygii): Evolutionary-ecological questions associated with the dynamics of repetitive sequences and the occurrence of polyploidy
Sember, Alexandr ; Ráb, Petr (advisor) ; Marec, František (referee) ; Král, Jiří (referee)
Ray-finned fishes (Actinopterygii) exhibit the greatest biodiversity among vertebrates. The vast majority of extant actinopterygian fish species belong to clade Teleostei - a lineage whose significant evolutionary success might have resulted from a teleost specific whole- genome duplication (TSGD) that occurred at the onset of this group, subsequent to its divergence from the rest of actinopterygian lineages. Despite the growing body of sequenced fish genomes and analyses of their transcriptomes, the largest contribution to understanding fish genomes comes from analyses of DNA content and from cytogenetics. Genomes of ray-finned fishes and especially those of Teleostei exhibit vast diversity and rapid dynamics of repetitive DNA sequences whose variability is reflected in a wide range of fish genome sizes and in the dynamics behind karyotype differentiation. Therefore, ray-finned fishes offer a unique opportunity to study genome variability as a driving force underlying morphological and ecological diversification, evolution and adaptation. Particularly, the mapping of repetitive DNA sequences by means of fluorescence in situ hybridization (FISH) has proven to be a very useful and informative approach during the last two decades and contributed greatly to our understanding of the fish genome...
|
|
|
Application of molecular and cellular biology methods in research of protozoa Eimeria
Vrba, Vladimír ; Škvor, Jiří (advisor) ; Čepička, Ivan (referee) ; Hampl, Vladimír (referee)
Eimeria is an apicomplexan parasite causing disease coccidiosis that is most prominent in poultry farming industry. This thesis is aimed to develop new molecular tools and resolve issues that would be a valuable contribution in the field from both research and industry perspective. Because immunity to Eimeria is strictly species- specific, it is important to know and recognize correctly all species that parasitize the host. Traditional diagnostic approaches rely on classical methods such as oocyst morphology determination under the microscope, measurement of prepatent period or in-vivo assessment of lesions caused by this parasite. However, diagnostics of individual species using these methods is very time-consuming and it is often unreliable, especially when mixture of multiple species whose parameters overlap is analyzed. Methods utilizing conventional PCR to distinguish species already exist, however, they lack advantages offered by quantitative real-time PCR (qPCR). The first aim of this thesis was to develop qPCR assays for detection and quantification of seven Eimeria species which infect chicken utilizing single-copy non-polymorphic targets in order to ensure maximal specifity and coverage of all strains of each species. Usefulness of this method was demonstrated by analysis of field...
|
|
|
delta subunit of bacterial RNA pol and its role in regulation of gene expression in B. subtilis
Dvořáček, Lukáš ; Krásný, Libor (advisor) ; Vopálenský, Václav (referee)
Delta subunit of bacterial RNA pol and its role in regulation of gene expression in B. subtilis. In this work I focus on regulation of eubacterial gene expression. First, I describe recent knowledge about a key stage of gene expression - transcription, focusing on regulation of trancription iniciation via small effector molecules (guanosine tetraphosphate, initiating nucleoside triphosphate) that are important for the regulation of ribosomal RNA. Second, in the experimental part of my work, I focus on the role of the _ protein, a subunit of RNA polymarase in gram positive bacteria, in transcription iniciation and its effects on regulation of RNA polymerase by the concentration of initiating nucleoside triphosphates.
|
guest ::
