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Regulation of yeast chronological ageing
Némethová, Ema ; Palková, Zdena (advisor) ; Motlová, Lucia (referee)
Yeast cells are able to differentiate during chronological aging and form different cell- types which acquire different viability. Chronological aging cells do not divide and thus mimic the aging of cells within multicellular organisms, such as mammals. Understanding of mechanisms of chronological aging of yeasts thus could help to understand similar processes of more complex organisms. Two types of cells, called "quiescent" and "non- quiescent" cells, are formed when yeast are grown in liquid medium. These cells have different morphology and gene expression and also differ in their metabolism. Yeast cells within agar-plate-grown colonies can sense different gradients of nutrients and signaling compounds and diversify to different cell types such as U and L cells, located in different colony regions. Both the "quiescent" and U cells are more vital and able to proliferate, whereas "non-quiescent" and L cells are less viable and exhibit stress features. Chronological aging involves many cellular processes including accumulation of storage compounds, mitochondrial activity, functions of specific genes and can be affected by calorie restriction and mild stress. Key words: chronological aging, yeast, differenciation of cell populations, metabolic change
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Inducible promoters and their use in yeast cell manipulation
Přibáňová, Gabriela ; Palková, Zdena (advisor) ; Vopálenský, Václav (referee)
Promoters which can be regulated by different chemical or physical factors are often used in cell manipulations. This thesis focuses predominantly on promoter systems which use light as an inductor. There are two main approaches to controlling a promoter by light. The first one uses so-called "caged molecules", chemical inducers whose inducing activity is "masked" by a photolabile protecting group. The second approach includes optogenetic systems, which can regulate transcription in cells. These systems are encoded in the DNA of the organism, and light is the only external regulatory stimulus. Photoreceptors that need a specific cofactor (chromophore) are the main components of optogenetic systems. There are several groups of photoreceptors classified by the type of chromophore and photoactivation mechanism. This thesis gives an overview of optogenetic systems used for transcription regulation and focuses on different photoreceptors and induction mechanism used. The systems using photocaged molecules are described as well. Furthermore, the thesis deals with light- systems in yeast as a model organism as well as organism used for biotechnological purposes. Finally, some limitations of light inducible promoters are discussed, including the chromophore type, the wavelength of the light, and the...
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Yeast colonies as a model of multicellular behaviour of microorganisms
Kuthan, Martin ; Palková, Zdena (advisor) ; Hašek, Jiří (referee) ; Kolarov, Jordan (referee)
- 32 - Závěr Již v úvodu jsem se zmínil, že mnohé laboratorní kmeny kvasinek ztratili vlivem domestikace schopnost filamentálního růstu. Ukázkovým příkladem cílené domestikace je laboratorní kmen S288C. Historie vzniku tohoto kmene je zajímavá a dokumentuje výrazný vliv genetiků na jeho vlastnosti. Velké množství kmenů S. cerevisiae používaných v laboratořích má společného předka kterým je kmen EM93. Tento diploidní kmen izoloval v Kalifornii v roce 1938 Emil Mrak z hnijícího fíku (MORTIMER and JOHNSTON 1986). Není však jasné, zda se jednalo o přirozenou mikroflóru fíků, nebo o kontaminaci komerčními pekařskými či kvasnými kmeny. Kmen EM93 je heterothalický a je schopen filamentálního růstu (LIU et al. 1996). Pro laboratorní účely ale nebyl úplně ʺpohodlnýʺ. Protože tvorba shluků buněk brání izolaci klonů vzniklých z jediné buňky a ztěžuje přesné určení počtu buněk v tekutých kulturách, snažili se genetici získat prototrofní kmen s neadherujícími, dobře resuspendovatelnými buňkami. Mnohonásobným křížením haploidních segregantů kmene EM93 s dalšími laboratorními kmeny a komerčními pekařskými kmeny vytvořil Robert Mortimer kmen S288C, jehož 90 % genomu pochází...
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TORC1 pathway regulators in yeast cells
Trubitsyna, Yana ; Palková, Zdena (advisor) ; Mašek, Tomáš (referee)
TORC1 ("Target Of Rapamycin") is highly conserved serine-threonine kinase that regulates cell growth, metabolism, proliferation and apoptosis. Some of the regulators and mechanisms of regulation of TORC1 activity are conserved in different eukaryotic organisms. In mammalian cells mTORC1 ("mammalian Target Of Rapamycin") is present that is homologous to yeast TORC1. The correct regulation of TORC1 activity is required for vitality of organisms and thus TORC1 and its regulations are investigated by many researches. A mutation in a single protein that is a part of TORC1 regulating complexes may result in a serious damage to the cell and to the organism. This thesis aims to describe the known TORC1 regulators in yeast and, in some cases, to compare TORC1 and mTORC1 regulations. Information on mTORC1 regulations that have not yet been identified in budding yeasts is also included. Keywords - TORC1, mTORC1, regulation, activity, yeast
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Temporal characteristics in the speech of guides in repeated texts
Hanušová, Kateřina ; Palková, Zdena (advisor) ; Veroňková, Jitka (referee)
The guide's speech is a very specific type of discourse. It is a semi-planned monologue performed, with minimal deviations from the pattern, several times in succcession. These qualities therefore allow for a study of each speaker's articulatory rate. This paper analyzes the articulatory and speech rate, pauses, as well as the distinction of prosodic units, using four guides' speeches (utterances?). Each of the speeches was studied in two iterations. This paper presents a detailed description of the observed qualities for each speaker and a comprehensive summary comparison of the guides' speech patterns.
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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)
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