| |
| |
| |
| |
|
Role mitochondria and retrograde signalization during development of yeast colony
Podholová, Kristýna ; Palková, Zdena (advisor) ; Heidingsfeld, Olga (referee)
Unicellular organisms such as yeast have been traditionally studied in shaken cultures, i.e., under condition in which they do not grow attached to solid surfaces as under natural conditions. In nature, cells only rarely live alone, but, on the other hand often create multicellular colonies or biofilms. During last years, yeasts started to be investigated also when grown on solid media. Our laboratory has previously developed special techniques for investigation of yeast colonies. These techniques allowed us to describe individual cell subpopulations within the colonies. The aim of this work was to prepare a series of mutant strains, describe morphology and ultrastructure of their colonies with the aim to contribute to understanding ofthe role of mitochondrial retrograde signalling pathway in the development of yeast colonies. This work describes expression of few selected genes (CIT2, RTG1, RTG2, and RTG3) in colonies of the parental strain BY4742 and of other mutant strains with deletion of one or more genes of RTG regulatory pathways. The results of the diploma thesis together with results of other authors became part of the publication (Podholová et al., 2016). Powered by TCPDF (www.tcpdf.org)
|
|
5' end modification of bacterial RNA
Pinkas, Daniel ; Krásný, Libor (advisor) ; Schierová, Michaela (referee)
Regulation of gene expression is a key feature of all organisms and can occur at several levels ranging from transcription initiation to protein degradation. An important mechanism of this process is regulation of mRNA stability by various modifications. The best known modification is eukaryotic 7mG cap, which protects RNA from RNase degradation. Recently, several new prokaryotic modifications have been discovered thanks to advances in liquid chromatography and mass spectrometry methods. One such a modification is nicotinamide adenine dinucleotide at the 5' end of some RNA. Nicotinamide adenine dinucleotide is analogous to 7mG cap. This study describes this phenomenon in context of bacterial transcription. Powered by TCPDF (www.tcpdf.org)
|
|
Pleiotropic effects of transcriptional protein Opi1 in Saccharomyces cerevisiae
Pavlíčková, Martina ; Schierová, Michaela (advisor) ; Mašek, Tomáš (referee)
Phospholipid biosynthesis in Sacchromyces cerevisiae is regulated by Ino2p-Ino4p activation complex and Opi1p repressor. The most highly regulated INO1 gene encodes inositol-3- phosphate synthase. This enzyme catalyzes the first step of the metabolic pathway of inositol synthesis. The Ino2p-Ino4p activation complex binds to the promoter of the target genes and interacts with other proteins necessary for activation (Snf1p, SAGA, SWI/SNF, INO80). The Opi1p represses transcription by direct binding to Ino2p and by interaction with other proteins (Sin3p, Cyc8p). The activity of Opi1p protein is mediated by cellular localization and by phosphorylation. The regulation of phospholipids is dependent on the growth phase and on the availability of precursors. Apart from its repressor activity, Opi1p affects mitochondrial metabolism, endoplasmic reticulum stress, cell size, mat formation and invasive growth.
|
|
Transcription factors driving periodic gene expression during the fission yeast cell cycle
Jordáková, Anna ; Převorovský, Martin (advisor) ; Paleček, Jan (referee)
The fission yeast Schizosaccharomyces pombe plays an important role in elucidation of the mechanisms of cell cycle regulation and characterization of the relevant effector molecules involved. The cell cycle of S. pombe consists of a prolonged period of growth (G2 phase), which is followed by a nuclear division (M phase), a very short G1 phase and DNA replication (S phase). Already during S phase formation of division septum occurs. Cell cycle progression is regulated at multiple levels. Although the yeast S. pombe is an extensively studied model organism, knowledge of the transcriptional network regulating progression through the cell cycle is still incomplete. Transcription factors are very important regulators of gene expression and therefore their characterization is the subject of research. At the transcriptional level, several key transcription factors have been identified that regulate periodically oscillating and interdependent waves of gene expression during the cell cycle. This study summarizes the current state of knowledge in the field of the transcriptional regulation of periodic gene expression in the fission yeast cell cycle.
|
|
Aptamers - binding and regulation abilities of RNA molecules
Oplová, Michaela ; Půta, František (advisor) ; Dzijak, Rastislav (referee)
Aptamers are single stranded ribo- or deoxyribonucleotides usually 20 to 80 nucleotides in length that occupy a complex three-dimensional structures by intramolecular interactions and bind to small target molecules with high affinity and specificity. Aptamers are generated in vitro using revolutionary technology SELEX (systematic evolution of ligand by exponential enrichment) and its modifications. They have recently attracted considerable attention of the scientific and medical community because of the fact that is possible to prepare aptamers binding practically any target molecule and this is making aptamers promising as diagnostic and therapeutic tools. Aptamers also exist naturally; aptamer domains have been found repeatedly as part of the regulatory elements of gene expression in bacteria, where they act as specific receptors for cellular metabolites. Domain TPP has been also found in plants, fungi and green algae.
|
|
Detection of Transcription Factor Binding Sites
Hlávka, Ondřej ; Vogel, Ivan (referee) ; Martínek, Tomáš (advisor)
Nowadays, it is very important to study gene expression mechanism in molecular biology. Gene expression is also regulated by sequence specific transcription factors which binds to regulatory regions of the genes. Searching for this specific sequences can be very problematic because transcription factor binding sites can be very degenerative. There are several possible methods that can be aplied to this problem. First part of this paper describes few algorithms for transcription binding sites search. Second part contains design and implementation of algorithm for searching binding sites of transcription factor p53.
|