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Regulation of potato tuber onset: the role of auxin
Myslivcová, Jitka ; Mašková, Petra (advisor) ; Havelková, Lenka (referee)
Potato (Solanum tuberosum) is an essential component of food worldwide. The process of tuber formation is controlled by the interplay of external and internal conditions. Understanding of the molecular basis of tuberization, including the effect of photoperiod, pointed to a key role of mobile signals. Among these morphogenic signals StBEL5 and POTH1 transcripts are involved, which are translated in the stolon and form a heterodimer regulating target genes with TTGAC tandem motifs, further an FT homologue, StSP6A, mobile from leaves to stolons as a protein. BEL5/POTH1 and StP6A signaling pathways seem to overlap. Phytohormones also play an important signaling role, i.a. auxins. During tuber initiation, IAA levels in stolon tissues increase. PIN transporters are likely to be involved in the redistribution of auxin in the stolon, but also LAX and ABCB transporters and components of auxin signaling pathway, Aux/IAAs and ARFs are also involved in the process. Although auxins are proved to play an important role during stolon-to-tuber transition, their exact role in the process is not sufficiently clarified. Auxin signaling is interconnected with BEL5/POTH1 and SP6A-mediated tuber signaling, as its target genes in the stolon include those that encode proteins involved in auxin biosynthesis (YUCCA1),...
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Changes in the contents of anthocyanins and photosynthetic pigments in barley leaves under the effect od climate change factors
Nikodymová, Michaela ; Albrechtová, Jana (advisor) ; Mašková, Petra (referee)
Ongoing climate change and its manifestations have a significant impact on agricultural crops, which are exposed to a wide range of abiotic (drought, high or low temperature, elevated UV radiation) and biotic (pathogens, pests) stress factors that can dangerously affect their growth and yield. One of the very important phenomena of climate change is the increasing concentration of CO2 and other greenhouse gases in the atmosphere. Manifestations of climate change, such as high temperature and drought, interact together with increased CO2 concentration, and these interactions can have serious effects on vegetation. This diploma thesis examines the effect of climate change factors and stress factors on the content of pigments with the importance of plant protection against stress, namely photosynthetic pigments and anthocyanins in barley leaves. The aim of the thesis is to find out whether and what are the differences in the response to these factors in two varieties of barley, differ in their resistance to photooxidative stress. The plants were grown in pots in growth chambers under controlled conditions and in flower beds in adjustable greenhouses with open roofs in the experimental station of plant ecophysiology Domanínek of the Global Change Research Institute of the Czech Academy of Sciences in...
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Modulation of BELL transcription factors balance as a tool for tuberisation strengthening in selected potato cultivars
Zounková, Andrea ; Mašková, Petra (advisor) ; Fischer, Lukáš (referee)
Potato (Solanum tuberosum) is the third most important crop in terms of human consumption. Hence understanding regulatory mechanisms controlling tuber initiation is significant not only from a theoretical but also practical point of view. Tuberization of S. tuberosum is a complex morphogenic process regulated by both, environmental conditions and inner plant status. Environmental conditions regulating the onset of tuberization have been known for a long time, but the molecular basis of tuber initiation has only recently been discovered, in particular using wild subspecies S. tuberosum subsp. andigena. BELL transcription factors are among the important components of the regulatory signalling network. The aim of this study was to modulate balance between the BELL transcription factors that induce and repress tuberization towards strengthening of tuber induction using two cultivars of Solanum tuberosum subsp. tuberosum, cv. Kamýk, resp. cv. Korela. To achieve this, transgenic lines carrying construct containing a part of coding sequence StBEL11, resp. StBEL29 in antisense orientation (AS) under control of constitutive promoters and lines carrying complete sequences of StBEL5 and StPTB6 genes under control of their native promoters were derived. We used the StBEL11 and StBEL29 AS constructs with the aim to...
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The Development of Fiscal Decentralization in Republic of Korea (South Korea) since 1987
Yeou, Junghyup ; Hnízdo, Bořivoj (advisor) ; Mašková, Pavla (referee)
The topic of this study is the fiscal decentralization (FI) in Republic of Korea (Korea). As a world-wide trend, FI has also been adopted and implemented in Korea, particularly since the democratization of 1987. As a redistribution of limited resources between national and sub-national government (SNG), FI is essentially political in that various political actors interact to achieve more resources. With the research problem of the fiscal tensions between SNGs and national government, the objective of this thesis is to assess the process of FI in Korea in its contexts since 1987. Research questions are: (1) why FI happened; (2) how national government and SNGs have interacted and how institutionalization has been devised; (3) how the outcomes can be interpreted in terms of socioeconomic development. The qualitative methodology is adopted in that it can describe phenomena in contexts and explore dynamic processes and find sequential patterns, which is relevant for the objective of this thesis. The specific methodology is interdisciplinary approach combining case, history, policy process, and institution approach. The main findings are; (1) democratization and globalization are the main driving factors of FI. (2) The policy process became more plural with the resistance against FI. As outputs, the...
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Cell cycle regulation in plants: the role of CDK activatory dephosphorylation at entry into mitosis
Mašková, Petra ; Macháčková, Ivana (advisor) ; Havel, Ladislav (referee) ; Vaňková, Radomíra (referee)
t I I I I I I I I I I I I I I Summary of PhD. thesis Cel1 division representsone of fundamentalattributesof all living creatuÍes.Basic molecular mechanisms operating during cell proliferation seem to be evolutionary conservedamongeukaryotes.The cell cycle is dividedin four subsequentphases;themost regulatoryeventsareconcentratedin Gr/S andGzlM checkpoints. The key regulatory proteins, cyclin-dependentkinases (CDKs), govern the progress throughthe whole cell cycle. Their function is strictly dependenton catalytic cyclin subunits.The correspondingcyclin partnerbinding CDK determinesthe time window of the specific CDlVcyclin complex actionin individual cell cycle phase.To becomefully active, the complex requiresfurtherposttranslationalmodificationincluding activatory phosphorylationanddephosphorylationof theCDK on specificaminoacidresidues. Plant cell cycle, besideswell-conservedmechanismscoÍlmonto all eukaryotes,exhibits other specific mechanismsresultingfrom plant survival strategy.The Gr/S transitionis stronglyaffectedby extemalandinternalsignals,mainlyphytohormonesandmetabolites, reflectingthe elementaryconditionssuitablefor accomplishmentof the whole cell cycle. The centralmoleculerespondingto thesesignalsat Gr/S is D cyclin, whoseexpressionis regulatedby cýokinin and sucrose(Riou-Khamlichi et aI.,...
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Analysis of possible resources for the support of gifted children in Czech elementary schools
Frimlová, Martina ; Háva, Petr (advisor) ; Mašková, Pavla (referee)
Diploma thesis "Analysis of possible resources for the support of gifted children in Czech elementary schools" deals with financing the support of gifted children in Czech elementary schools from multiple sources. It starts from the finding that there are available resources both from government and non-government subjects, and that these resources can be used to support special pedagogical care of gifted pupils. It tries to analyze these resources (both financial and non-financial) from the point of view of an elementary school, which aims to give special treatment to gifted children, as it is suggested by legal documents, but cannot influence national policy. When searching for resources to support gifted children, the school eventually faces the fact that directive state funding is inadequate. So the school is forced to resort to searching for alternative sources. It is, however, not a system solution of the problem. Within the process of solving the research problem, 22 most significant resources were identified, including the basic resource - directive state funding. Data obtained about these resources were analyzed within historical and legal context. The result is findings about important characteristics of each of these resources, including legal validity of use, political continuity, amount and...
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Mutations in brassinosteroid biosynthetic genes and their effects on plant phenotype
Frimlová, Klára ; Rothová, Olga (advisor) ; Mašková, Petra (referee)
Brassinosteroids are important group of phytohormones, whose presence affects anatomy, morphology and development of plants. They occur in all vegetative and mainly generative organs. Brassinosteroids are biosynthesized via two main paths named early C-6 oxidation pathway and late C- 6 oxidation pathway. Brassinosteroid biosynthesis is catalyzed by enzymes from the group of cytochrome P450. Gene mutations - which affect brassinosteroid biosynthesis - have been studied especially in Arabidopsis thaliana L., Pisum sativum L., Solanum lycopersicum L. and Oryza sativa L. Mutations lead to changes in the composition and amount of brassinosteroids in plants. The reduced content of brassinosteroids is manifested by typical phenotype that includes reduced growth, reduced size of plant organs, and dark green leaves in mutant plants. The mutant phenotype can be reversed by exogenous application of brassinosteroids, which is nevertheless dependent on the concentration of the brassinosteroids used. Higher concentrations of brassinosteroids cause mostly inhibition of root elongation. Keywords: brassinosteroids, biosynthesis, mutant, phenotype
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Regulation of floral initiation in woody perennials
Čermák, Vladimír ; Mašková, Petra (advisor) ; Čermák, Vojtěch (referee)
Floral initiation is an important process for temperate woody perennials that affects the subsequent development of the flower. Although this process is well known in annual plants such as Arabidopsis thaliana, not much research has been done in woody plants. This review summarizes the knowledge about mechanisms of flowering induction in woody perennials, compared to the findings in model plants, especially A. thaliana, including factors involved in the regulation of the flowering process. In particular, FT-like genes and TFL1-like genes, which play an important role in the regulation of flowering induction, are discussed in detail. In temperate woody plants the dormancy period follows the floral induction before the floral development. Periodic regulation of this stage is controlled endogenously and, in addition to other factors, it is affected by expression of DAM genes. The genetic mechanisms regulating endodormancy release in woody perennials are similar to vernalization in herbs. Better understanding of processes such as the floral induction and endodormancy release can help us to develop cultivars with a modified flowering time.
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The role of the Czech public media in the pension reform discourse
Tomíčková, Adéla ; Háva, Petr (advisor) ; Mašková, Pavla (referee)
The thesis 'The role of the Czech public media in the pension reform discourse' aims to provide a critical reflection on the role of the Czech Television and the Czech Radio in the debate over the changes in the pension scheme of the Czech Republic. The principal method used for that is the discourse analysis, which comprises quality and quantity analysis of the media output, interviews and personal observation. The research project focuses on the context the debate over the pension reform occurs and how it is presented in the public media. The theoretical part summarizes the theoretical concepts used in the research project, i.e. concepts from the field of public policy, social policy, mass communication and discourse analysis. The empirical part examines the institutional development of the pension reform, its variations in political, scholarly (Czech and international) and public discourse. The major part of the research project is based on the discourse analysis of the pension reform discourse in the Czech public media. The role of the public media in the pension reform discourse is deduced on the basis of the theoretical and empirical parts.
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