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Non-traditional roles of formins besides actin nucleation
Metlička, Jáchym ; Cvrčková, Fatima (advisor) ; Opatrný, Zdeněk (referee)
Formin homology 2 (FH2) domaincontaining proteins (formins) have, since their discovery in 1990, been observed in all analyzed species of eukaryotic kingdoms. Our knowledge of structure and function of the defining FH2 domain has greatly increased over the last couple of years. Its function in nucleation, polymerization and processive capping of actin filaments designates formin protein family an important cytoskeletonremodelling factor. But FH2 domain is just one part of the puzzle additional optional conserved peptide structures surrounding it, as well as concrete variation of the FH2 domain itself, greatly influence the functional properties and cellular localization of the resultant formin protein. Formins have been implicated in variety of cellular processes, which often (but not always) involve the cytoskeleton e.g. Factin network management, crosstalk of Factin filaments and microtubules or plasma membrane. They also partake in processes integral to cell division, function in conserved signalling pathways and much more. This thesis explains the structure and function of FH2 and FH1 domains, outlines the main formin phylogenetic clades in multicellular eukaryotes and reviews various roles that formins fulfill or are thought to fulfill. Such goal, however, is very bold and (considering the...
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Transgenic crops and third world
Andrová, Julie ; Opatrný, Zdeněk (advisor) ; Cvrčková, Fatima (referee)
The issue of transgenic crops and the third world is mostly neglected in secondary education. In view of the fact that it is an interesting topic that gains greater importance worldwide, it would deserve the place in secondary education. It is not necessary to submit information about this topic only in the text form to students but teaching methods that force the students to gain information actively, can be used. Text for teachers was created in diploma thesis. The text could serve as a source of information for teachers in preparing for the lesson about this topic. Then test for students was created. The test consists of tasks that are inspired by the PISA. Students have to gain information actively from the texts in the tasks to solve the tasks correctly. The test consists of three thematic areas (transgenic crops, golden rice, vaccination and edible vaccines) and 16 questions (31 including the sub-questions). The test was verified on a sample of 82 grammar school students at the age of 16 to 19 years. The students were of the four classes in four grammar schools. The students recorded their answers in a data sheet. The data sheet included additional questions that sought the views and attitudes of students towards texts and questions in the test. The teachers completed the questionnaire. The...
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GM crops for new food, pharmacological and technical use: inovation of secondary school study
Koblihová, Kateřina ; Opatrný, Zdeněk (advisor) ; Drda Morávková, Alena (referee)
The demand for plant and other production is increasing with the growth of human population when the territory where plants can be grown is continually decreasing. The present agricultural production of food, industrial materials and drugs of plant origin is not enough for people, as for the effort to achieve higher environmental comfort, especially in developed countries. We are trying to find a simpler, cleaner and cheaper ways of crop production. The genetic modification is one of the modern ways how to achieve this goal. Students get a lot of information about this topic from various sources, but mainly just from the internet and television. It is recommended that students should be able to compare information received from the media with school knowledge as for avoiding opinion pressure and manipulations.
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Following the Arp2/3-based processes in plant cells
Fišerová, Jindřiška ; Opatrný, Zdeněk (advisor) ; Binarová, Pavla (referee) ; Dráber, Pavel (referee)
1. ABSTRACT An actin cytoskeleton comprises an essential cytoskeletal structure that organizes a cytoplasm during number of processes occurring in animal and plant cells, such as cell division and growth, formation of membrane protrusions and cellular movement or cytoplasmic streaming. A dynamic actin net and an exact spatial and temporal actin filament organization is, therefore, necessary for correct growth processes and development of multicellular organism. Depolymerization and re-establishment of actin arrays is mediated by actin associated proteins. Among them, an Arp2/3 complex (actin related protein 2 and 3) plays an important role as a catalyst of the actin filament nucleation and, thus, enables the formation of dynamic actin network. In non-plant cells, Arp2/3 complex-dependent polymerization of actin filaments is required for movement of whole cells (fibroblasts or keratocytes), it drives organels and pathogens throughout the cell or mediates endocytic processes. The role of the Arp2/3 complex in non-motile plant cells is despite the considerable effort over last three years far from being understood. Unlike animals, where loss-of-function mutations in the Arp2/3 complex are lethal, only limited number of cell types show significant phenotype in Arabidopsis mutants. The evidence exists that the...
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Rodina auxinových přenašečů PIN: funkční a evoluční pohled
Skůpa, Petr ; Zažímalová, Eva (advisor) ; Hejátko, Jan (referee) ; Opatrný, Zdeněk (referee)
Growth and development of plant body is dependent on correct and effective integration of information about current deployment of its body parts, as well as on perception and transduction of inputs from environment. Multiple developmental processes within plant body are determined by specific and tightly controlled distribution of molecule with unique signaling mission within plant development - auxin. Spatial distribution of auxin is co-determined by plethora of tightly controlled processes, and the polar auxin transport plays unique role among them. PIN proteins are the plant-specific family of secondary transporters driving movement of auxin across membranes. With their frequent asymmetrical localization within cells, specific expression patterns in developing tissues and their reactiveness to external cues they secure unique, dynamic and asymmetric distribution of auxin within the plant body. This dissertation thesis is focused on characterization of the role different PIN proteins play in determining cellular auxin homeostasis and consequent formation of auxin gradients. Controlled overexpression of PIN proteins in tobacco cells showed, that PIN4 and to some extent also PIN6, function as the direct auxin efflux carriers. In the cellular auxin transport they play the role analogous to other...
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Molecular mechanism of transport of plant hormone auxin into cells
Laňková, Martina ; Zažímalová, Eva (advisor) ; Stiborová, Marie (referee) ; Opatrný, Zdeněk (referee)
The non-uniform distribution of the plant growth regulator (phytohormone) auxin is known to mediate many fundamental processes in plant development. Auxin is transported through the plant body either via vascular pathways or from cell to cell by specialized polar auxin transport machinery. This machinery consists of a balanced system of passive diffusion combined with the activities of auxin influx and efflux carriers. This work is focused on the processes that are involved in the uptake of auxin into plant cells. On the basis of molecular-biological and biochemical characterization, the function as an auxin influx carrier was confirmed for PaLAX1 protein from wild cherry (Prunus avium). The sequences of isolated cDNA of the PaLAX1 gene and of its protein product are highly similar to both the cDNAs and the corresponding protein products of the AUX1/LAX-type genes, coding for putative auxin influx carriers in model plant A. thaliana. On the level of organs and single cells, we have shown that the overproduction of PaLAX1 in transgenic lines resulted in an increase of the content of native auxin indole-3-acetic acid as well as of the uptake of synthetic auxin, 2,4-dichlorophenoxyacetic acid. Further, the mechanism of action of putative auxin influx inhibitors 1-naphthoxyacetic acid (1-NOA),...
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