|
|
The relationship between splicing and posttranslational modifications of chromatin in Saccharomyces cerevisiae
Kovaľová, Libuša ; Folk, Petr (advisor) ; Čáp, Michal (referee)
Protein Prp45, the yeast ortholog of the human transcription coregulator SNW1/SKIP, has been previously associated only with the regulation of pre-mRNA splicing. However, our laboratory found that protein Prp45 genetically interacts not only with the proteins involved in pre-mRNA splicing, but also with factors important for transcription elongation and with chromatin modifying enzymes. Our data and the information about the human ortholog SNW1/SKIP suggest that Prp45 could serve as a regulator coupling splicing, transcription and chromatin state in S. cerevisiae. The main aim of this diploma thesis was to find out whether the protein Prp45, which is essential for cotranscriptional assembly of the spliceosome, affects posttranslational modifications of chromatin on transcribed genes. Using chromatin immunoprecipitation, the influence of prp45(1-169) mutation on trimethylation of histone H3 at lysine 4 and acetylation of histone H3 at lysines 9, 14 and 18 on transcriptionally active genes was not confirmed. The other aim was to analyse the behavior of cells synchronized by α-factor by using flow cytometry. According to our results, prp45(1-169) mutation leads to the prolongation of the cell cycle. For the purpose of monitoring the dynamics of nucleosomes in S. cerevisiae strains, the system of...
|
|
|
Eukaryotic translation initiation factor 3 and its role in plant translation regulation
Raabe, Karel ; Michailidis, Christos (advisor) ; Retzer, Katarzyna (referee)
After transcription, mRNA translation is another highly regulated process in gene expression. In plants, translation regulation plays an important role during progamic phase, fertilization and seed development, where synthesized transcripts are stored and selectively translated later in development. Translation regulation is also broadly used in stress responses as a fast and flexible tool to change gene expression; therefore, it plays an essential role in the survival strategy of sessile organisms like plants. Both regulation of the global translational rate as well as selective regulation of specific transcripts modulate the final gene expression response. Most of the regulatory mechanisms are concentrated in the stage of initiation, which is facilitated by several translation initiation factors. Eukaryotic translation initiation factor 3 (eIF3) is the largest and most complex of these factors, consisting of 12 conserved subunits. Its key function in the initiation is to scaffold the formation of the translation initiation complex and in the scanning mechanism accuracy. In past decades, additional eIF3 functions were discovered acting upon the whole translation cycle, including its importance in global and specific translation regulation. The aim of this work is to review eIF3 functions and to...
|
|
|
Role of long non-coding RNAs in plants
Klodová, Božena ; Honys, David (advisor) ; Novotný, Marian (referee)
Long non-coding RNAs (lncRNAs) represent a group of transcripts with length greater than 200 nucleotides having low coding potential. It is a group of regulatory ribonucleic acid (RNA) still not fully understood but with significant potential in many biological processes across different species. For animals, many important lncRNA regulators and their roles in a range of events including their involvement in carcinogenic diseases have been reported. However, particular mechanisms of functions are often yet to be discovered. Considering plants, economically important species such as rice, maize or soybean are of particular interest. There are still only several fully annotated transcripts. However, with the constant improvement of sequencing and bioinformatic methods, the importance of lncRNA (for example in pathogen resistance or plant reproduction) becomes clear. This bachelor thesis reviews up-to-date knowledge about lncRNAs and their roles in plants. It also describes the difficulties of lncRNA research and discusses their future potential.
|
|
|
The structure and role of type III secretion system and other virulence factors in pathogenesis of pertussis
Štipl, Daniel ; Večerek, Branislav (advisor) ; Pinkas, Dominik (referee)
Bordetella pertussis is a significant human pathogen which colonises a respiratory tract. The infection with B. pertussis results in serious and highly contagious disease called pertussis or whooping cough. B. pertussis produces wide range of virulence factors such as pertussis toxin, adenylate cyclase toxin, dermonecrotic toxin, tracheal cytotoxin, adhesins and type III secretion system (T3SS). The BvgAS is two-component signal transduction system that provides the complex regulation of B. pertussis virulence. The virulence factor T3SS is used by some Gram-negative bacteria to colonise the host and is responsible for pathogenesis of the infection. T3SS takes a role in virulence of mammalian pathogen B. bronchiseptica, closely related to B. pertussis. The importance of T3SS in virulence of B. pertussis remains to be investigated. Significant advance in structure, function and regulation of the most of virulence factors have been accomplished in last few decades. The causative agents of pathogenesis in that infection remain unknown. Key words: Bordetella, T3SS, gene expresssion regulation, virulence factor, pathogenesis
|
|
| |
|
| |
|
| |
|
| |
|
| |
|
| |
guest ::
