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Temporal characteristics of tone units in the speech of professional speakers
Hrachová, Jana ; Veroňková, Jitka (advisor) ; Palková, Zdena (referee)
This thesis deals with temporal characteristics of tone units in read speeches of professional speakers. The main goal of the research is to follow variability of the articulation rate (AR) within tone units. Thus, the domain where we investigate AR is the tone unit and we also deal with the general articulation rate. Read narrations in Czech in wildlife documentaries represented the studied material. To verify the statistical significance, we used the linear mixed effects model and the ANOVA test. The results of the measurement of the general average articulation rate within the narrations showed that the values of one speaker were significantly different from those of the other speakers. Interpersonal variability was also proved by the ANOVA tests and intrapersonal variability was also evidenced. The average AR values with regard to linear segmentation proved to be relatively uniform. Statistical verifications did not prove any statistical significance either. In our analyses of tone units, we investigated whether AR was influenced by the size of tone units in prosodic words, further by the position of the prosodic word in the tone unit, and what were the directions of AR changes inside the unit. Statistical tests were used to verify the significance of the impact of the tone unit size as well as...
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Role of the low-molecular metabolites in the development of yeast colonies
Bezdíčka, Martin ; Palková, Zdena (advisor) ; Dostál, Jiří (referee)
Previous research of colonies formed by yeast Saccharomyces cerevisiae growing on glycerol agar medium revealed two major cell types of U and L cells that are formed within these colonies. This colonial cell differentiation seem to be caused by communication among yeast cells as well as whole colonies and affected by changes in the environment (for example changes in nutrients). Studies of U and L cells showed that U cells are more resistant against biological, chemical and physical stresses than L cells. The aim of this thesis was to isolate U and L cell types and investigate their resistance against selected low molecular weight chemical substances produced in Ehrlich pathway. Ehrlich pathway was discovered in 1907 and was classified as amino acid catabolic pathway in yeast S. cerevisiae. The low molecular intermediates are formed in Ehrlich pathway which are called fusel (original name from German) alcohols and acids. These chemical substances are widely used in food industry and cosmetics especially because of their aroma. Several studies provided indications that these chemical substances may affect development of colonies and important yeast functions such as switching to the pseudohypfal growth of S. cerevisiae cells. Some chemical substances of the Ehrlich pathway were selected and their effects on...
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Function and localization of the SUN family of proteins in yeast populations
Kuznetsov, Evgeny ; Palková, Zdena (advisor) ; Janderová, Blanka (referee) ; Malcová, Ivana (referee)
The SUN family of proteins (Uth1p, Sun4p, Sim1p, Nca3p) is a group of fungal proteins similar to cell wall glucanases and highly homologous in their 256 long C- terminal amino acid domain. Our previous studies on yeast colony development revealed that members of the SUN family of proteins may be involved in the aging process and may play important role for survival during the development and grow of multicellular yeast populations. Our lab implemented a microarray analysis of expression changes in Saccharomyces cerevisiae colonies, which showed significant changes in the expression level of the SUN family member - UTH1. In addition, a strain with a disrupted UTH1 gene displayed a poorer grow and rate of survival in yeast colonies in comparison to the wild type. However, in this work, we focused on identifying and better understanding the functions of particular SUN proteins and determitation of their exact localization. Interestingly, some SUN family proteins have dual localization (Uth1p, Sun4p) to the mitochondria and cell wall and may thus be involved in mitochondrial and cell wall function. In this thesis, the "Results and discussion" section is divided into two parts as follows: the first part addresses questions concerning localization, oxygen-depended regulation and the possible involvement...
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Autophagy and other processes in colonies of natural yeast strains
Novosadová, Zuzana ; Palková, Zdena (advisor) ; Groušl, Tomáš (referee)
Abstract The yeast Saccharomyces cerevisiae on solid media forms multicellular colonies. Cells within colonies undergo differentiation and metabolic diversification, including formation of two layers of cells called Upper and Lower cells. The metabolic activity of U and L cells is different. For instance a higher level of autophagy was observed in U cells. This thesis includes a literature review of molecular mechanisms of autophagy in yeasts. Yeast colonies, under starvation conditions, produce volatile ammonia signal. This signal allows them communicate over a distance. Studies, revealing cell differentiation within colonies and ammonia signalling among colonies, were performed in colonies of laboratory strains. Strains isolated from nature, so-called wild strains, form distinct structured colonies, termed fluffy. Yeast within fluffy colonies also form different cell types. However the situation seems to be more complex that within smooth colonies of laboratory strains. Strains were constructed during this study, which express marker proteins Icl2p, Pox1p, Mae1p, Pma1p, Pma2p, Ino1p, Met17p and Atg8p fused with fluorescent labels in order to study cell differentiation and other processes within fluffy colonies. Furthermore, a new system for ...
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Structurally motivated analysis of intonation downtrends in three Czech accents
Pospíšilová, Iva ; Volín, Jan (advisor) ; Palková, Zdena (referee)
This thesis pursues the topic of downtrends in Czech intonation in correlation with the geographical origin of speakers. The theoretical part is devoted to the section on the suprasegmental plateaux of the language - the intonation, the intonation variability, and mainly the intonation downtrends. It also brings a selective dialectical description of three Czech regions, which this thesis deals with: Plzeňsko, Štítecko and Břeclavsko. The practical part is targeted to the intonational analysis of the speech material (74 speakers overall), acquired in the previously mentioned regions. The average caliber of the guidelines, acquired by the application of the regressive line, were − for the given groups of speakers − compared and annotated, considering the age and sex of the respondents, (ideal) number of tacts or relative presence of the finding questions. key words: intonation, intonational downtrends, region, speaker, regressive line
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Yeast retrograde signaling pathway between mitochondria and the nucleus
Podholová, Kristýna ; Palková, Zdena (advisor) ; Fraiberk, Martin (referee)
Retrograde signaling pathway is the pathway between mitochondria and nucleus. This pathway helps Saccharomyces cerevisiae to cope with worsening of conditions of life, such as depletion of rich nutrient sources and necessity of use poor resources, reduction of mitochondrial membrane potential, or loss of mitochondrial DNA causing disturbances in the citric acid cycle. Most of these conditions are associated with aging yeast populations. Key retrograde pathway proteins include RTG transcription factors Rtg1p/Rtg3p and cytoplasmic protein Rtg2p. Retrograde pathway is upregulated by several positive and negative regulators including the TOR pathway, which negatively regulates retrograde pathway. The retrograde pathway target genes include genes coding for tricarboxylic cycle enzymes, peroxisomal enzymes, transporters and other enzymes of anaplerotic pathways. Retrograde response help cells to modify their metabolism so that they are able to overcome unfavorable environmental conditions in which they live. Powered by TCPDF (www.tcpdf.org)
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Nucleotide metabolism in the development of Saccharomyces cerevisiae colony
Dvořáková, Markéta ; Palková, Zdena (advisor) ; Seydlová, Gabriela (referee)
Yeasts are unicellular microorganisms which are able to form colonies. The morphology of colonies is characteristic for the strain and differs according to particular growth conditions. Saccharomyces cerevisiae colonies are able to produce volatile ammonia which functions as a signalling molecule alarming nutrient depletion (PALKOVÁ et al. 1997). Changes in gene expression, metabolism and ammonia production occur during the development of giant S. cerevisiae colonies. Genes with changes in expression have been identified to be involved in ammonia transport, amino acid metabolism and also in nucleotide metabolism. Genes, whose deletion may affect the induction of ammonia production have been described (ČÁP et al., 2010), (VÁCHOVÁ a PALKOVÁ 2005), (PALKOVÁ et al. 2002). This work is focused on studying of an impact of deletions of selected genes involved in nucleotide metabolism, as well as of changes in extracellular concentrations of different bases on growth, morphology, ammonia production, cell morphology and differentiation of giant S. cerevisiae colonies. S. cerevisiae strains producing Gfp-tagged proteins (Ade4p-Gfp, Adk1p-Gfp, Urk1p-Gfp, Fcy2p-Gfp, Fur4p-Gfp, Fcy22p-Gfp) have been constructed and analyzed. Development of S. cerevisiae giant colonies with deletions of selected genes (ADE5,7,...
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Sch9p and Rim15p signaling pathways in yeast colony development
Mikešová, Jana ; Palková, Zdena (advisor) ; Heidingsfeld, Olga (referee)
On solid surfaces, laboratory strain Saccharomyces cerevisiae BY4742 forms horizontally and vertically stratified colonies. Central part of the colony differentiates into U and L cells occupying upper and lower colony regions, respectively. There are many morphological and physiological differences between these two cell types. However, molecular mechanisms of the vertical stratification are still largely unknown. In this study, I analyzed effects of the deletion and overexpression of Sch9p a Rim15p kinases with crucial role in nutrient sensing pathways, of transcription activators Msn2p and Msn4p involved i stress response and of post-diauxic shift transcription factor Gis1p in yeast colony differentiation and U and L cell survival. Microscopic analyses showed changes in morphology of cells in colonies of these strains and decreased ability of vertical stratification in colonies of the strain rim15Δ and partially in colonies of the strain PTEF-SCH9. Moreover, changed level of these proteins significantly affected long-term survival of U and L cells. Obtained data suggest an involvement of nutrient sensing pathways in colony formation and development.
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Temporal accuracy of speech imitation in two age groups of children
Prachová, Pavla ; Volín, Jan (advisor) ; Palková, Zdena (referee)
The goal of this thesis was to test the ability of speech imitation in terms of temporal accuracy in two age groups of children. The first age group comprised 8 girls and 8 boys at the age of 10 to 11 years; the second group consisted of 8 girls and 8 boys at the age of 12 to 13 years. For the purpose of the experiment a perception-production test was created - it consisted of six, nine and twelve syllabic declarative sentences which contained two, three and four trisyllabic stress- groups. The task of the participating children was to repeat the sentences in three manners: in exactly the same words as they had heard them, and then by using the syllable /na/ and /ba/. Even though the children were able to meet the task, in some cases deviations occurred, such as deformations of the sentences in a certain way. Accuracy of imitation was investigated through average deviations from the model sentences. Based on the obtained values we identified the factors of length and composition of the task items and also the manner and order of imitation. We were also interested whether age and gender of respondents affect the accuracy of imitation. Key words speech rhythm, tempo, duration, stress-group, average deviation, imitation, children
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TOR signalling in yeast
Šimek, Jan ; Palková, Zdena (advisor) ; Španielová, Hana (referee)
TOR ("Target of rapamycin") protein, a highly conserved Ser/Thr protein kinase, is a central component of signalling network that controls cell growth in diverse eukaryotic organism, ranging from yeast to man. TOR proteins were first identified in yeast Saccharomyces cerevisiae in 1991 as the targets of the antifungal and immunosupressive agent rapamycine. In contrast to most eukaryotes, yeast contains two TOR homologues , Tor1p and Tor2p. These proteins are components of multiprotein complexes TORC1 and TORC2. TORC1 is specifically inhibited by rapamycine and controls cell growth in response to quality of the available nutrients. TORC2, which is insensite to rapamycine, regulates actin polymerization, sphingolipid biosynthesis and endocytosis. This work is focused on description of both TOR complexes, especially on downstream and upstream regulation of TORC1. Powered by TCPDF (www.tcpdf.org)
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