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Synthesis of Lanthanidocene Based Compounds
Pospíšek, Marek ; Zmrzlý, Martin (referee) ; Richtera, Lukáš (advisor)
The aim of this bachelor thesis is to summarize the issues of the polymerization catalytic systems based on lanthanidocene complexes. These complexes are subsequently divided by the structure into four basic groups. One part of this work deals with an overview of the most interesting results of the catalytic systems, which are then analyzed and assessed either in its entirety or point of view of catalytic activity, living mechanism of polymerisation and stereo or regioselectivity. The focus is also placed on type of monomers or the conditions of polymerization. In this part of thesis are also described general methods for their synthesis. Found analogies and generalization are commented from the point of view of the design of the catalytic systems for the purpose of choosing the stereo or regioselectivity, molar mass and its distribution. This gives significance to these complexes as catalytic systems for obtaining the required polymer properties. The acquired knowledge is used for the theoretical design of the catalytic system for controlled polymerization.
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Chemical modifications of polypropylene surfaces
Pospíšek, Marek ; Petrůj, Jaroslav (referee) ; Kučera, František (advisor)
Diploma thesis is focused on modification and characterization of polypropylene (PP) products surfaces by the chemical way. In theoretical part of thesis are summarized the current knowledge of this topic including characterization methods. Polypropylene surfaces were modified by acrylic monomers (acrylic acid, acrylic acid with 20 mol% content of sodium acrylate and acryl amide). Modified surfaces were characterized by infrared spectroscopy with ATR technique. The comparative parameter was carbonyl index determined from absorption peaks of functional methyl groups (2950 cm-1 ) and functional carbonyl groups (1700-1750 cm-1) of FTIR-ATR spectra. Determination of effect of initiator concentration on the modification process was done for acetophenone and benzophenone. There were determined the time dependence of carbonyl index for time from 0 to 600 s of mentioned monomers. In the same condition were modified test specimens designed for preparation of adhesive joints. Joints were bonded by cyanoacrylate adhesive that provide reaction with surface of polyacrylic acid. There were founded conditions of modification that provided strength of adhesive joints higher than strength of original PP. There were identified changes of surface roughness by using of confocal microscopy.
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Interaction partners of protein eIF4E2 in human cells
Pospíšilová, Klára ; Pospíšek, Martin (advisor) ; Hálová, Martina (referee)
Protein eIF4E2 belongs to the family of eukaryotic translation initiation factors 4E, but it does not participate in translation initiation under normal circumstances. Its main role lies in translational repression of specific mRNAs. Nevertheless eIF4E2 takes part in translation initiation as a subunit of a specific translation initiation complex in hypoxic conditions. The exact mechanism in which eIF4E2 takes part in either of these processes is not known. One way to study the role of eIF4E2 in the cell is to find out what other proteins does eIF4E2 interact with. The goal of this work was to seek out potential eIF4E2-interacting partners in the HEK293 cell line using immunoprecipitation followed by mass spek- trometry. Apart from finding individual proteins the goal was to identify eIF4E2-containig protein com- plexes in HEK293 cells. A second line of work was preparation of a system for screening inhibitors of the interaction between eIF4E2 and eIF4G3. The main result is finding potential new eIF4E2-intera- cting partners in human cells.
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Noncanonical functions of IL-1α
Novák, Josef ; Pospíšek, Martin (advisor) ; Černý, Jan (referee) ; Brdička, Tomáš (referee)
1α (IL 1α) is a multifunctional cytokine 1α is 1α independent on the receptor sig 1α is responsible for 1α to the plasma membrane. 1α activates express κB, binds to 1α 1α 1α to the plasma membrane 1α to signal 1α is required for membrane 1α exter 1α anchoring 1α 1α 1α with tumor suppressor p53 following genotoxic stress is further described in human cell 1α coloca
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Mechanisms used by SARS-CoV-2 for escape from innate host defense
Rybová, Lucie ; Němečková, Šárka (advisor) ; Pospíšek, Martin (referee)
SARS-CoV-2 of the Coronaviridae family causes the disease called Covid-19. It has a number of structural, non-structural and accessory proteins that interfere with the host's immune response and help the virus escape this response and survive in the host. The most important escape mechanism is suppression of host interferon function. Molecules causing inhibition of the host's innate immunity are encoded from the region of the virus genome ORF1a and ORF1ab. This work provides a summary of the characterization, morphology, genome, replication cycle, innate immunity mechanisms involved in host defense against infection, and escape mechanisms of SARS-CoV-2. Keywords: SARS-CoV-2, virus, morfology of SARS-CoV-2, SARS-CoV-2 genome, structural proteins, nonstructural proteins, innate immune system escape, IFN dysregulation, TLRs, SARS-CoV-2 variants, Covid-19
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Noncanonical human eIF4Es in and out of the RNA granules
Frydrýšková, Klára ; Pospíšek, Martin (advisor) ; Půta, František (referee) ; Valášek, Leoš (referee)
Eukaryotic translation initiation factor eIF4E1 (eIF4E1) plays a pivotal role in the control of cap-dependent translation initiation, occurs in P- bodies and is important for the formation of stress granules (SG). Human cells encompass two other non-canonical translation initiation factors capable of cap binding although with a lower affinity for the cap: eIF4E2 and eIF4E3. Here, I investigated the ability of individual eIF4E family members and their variants to localize to SGs and P-bodies in stress-free, arsenite and heat shock conditions. Under all tested conditions, both eIF4E1 and eIF4E2 proteins and all their variants localized to P-bodies unlike eIF4E3 protein variants. Under both arsenite and heat stress conditions all tested variants of eIF4E1 and the variant eIF4E3-A localized to SGs albeit with different abilities. Protein eIF4E2 and all its investigated variants localized specifically to a major part of heat stress-induced stress granules. Further analysis showed that approximately 75% of heat stress-induced stress granules contain all three eIF4Es, while in 25% of them eIF4E2 is missing. Large ribosomal subunit protein L22 was found specifically enriched in arsenite induced SGs. Heat stress-induced re- localization of several proteins typical for P-bodies such as eIF4E2, DCP-1, AGO-2...
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Structure and function of IRES elements in yeast
Černý, Jiří ; Pospíšek, Martin (advisor) ; Fišer, Radovan (referee)
Translation initiation is an important step in control of gene expression. Cellular mRNAs are usually translated via classical cap-dependent pathway, but some of them can also be translated by an alternative pathway like IRES mediated one. In the first part of my work I studied a possibility of IRES dependent translation initiation of RRN3 and BAS1 mRNAs from yeast Saccharomyces cerevisiae. I inserted BAS1 and RRN3 5'UTR into the intercistronic spacer of pFGAL4h and its promotreless version and measured the activity of secondary reporters in enegineered yeast strains. My data indicates presence of cryptic promoter in tested regions. To confirm this results I first inserted the RRN3 5'UTR into the intercistronic region of another bicistronic plasmid - pRFh and measured expression of second cistron. The results were similar like in the case of pFGAL4h system. The presence of shorter RNAs transcribed from cryptic promoter within the intercistronic region was shown using real time PCR. My quest in the second part of this work was to prepare RNAs useful for next investigation of translation control of lariat capped RNAs produced by GIR1 ribozyme in a slime mold Didymium iridis. I have prepared a wide set of DNA molecules coding different versions of GIR1 in front of the firefly luciferase ORF which served as...
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Transcriptional regulation of miR-17-92 microRNA cluster during macrophage differentiation.
Rybářová, Jana ; Stopka, Tomáš (advisor) ; Pospíšek, Martin (referee)
miR-17-92 cluster (Oncomir1) encodes seven microRNAs (miRNA, miR) regulating many biological processes including proliferation, differentiation or apoptosis. Overexpression of microRNAs encoded by miR-17-92 cluster is found in a number of tumors including acute and chronic myeloid leukemias (Dixon-McIver et al., 2008; Li et al., 2008; Venturini et al., 2007). Myeloid progenitors express miR-17-92 cluster at a high level, while macrophage differentiation associates with its downregulation. Our laboratory found, that miR-17-92 cluster is repressed by transcription factor Early growth response 2 (Egr2) upon differentiation of primary myeloid PUER progenitors, induced with transcription factor PU.1. Aim of this thesis is to further test the abovementioned data by preparing a reporter vectors set, carrying various fragments of miR-17-92 putative promoter, which enables us to study regulation of transcription of miR-17-92 cluster. This task complicated by presence of increased GC content of the miR-17-92 promoter was successfully accomplished resulting in amplification of eight fragments containing the various parts of miR-17-92 promoter including region -3.3 to 0 kb relative to the start of miR-17-5p sequence, that were inserted into pGL3 reporter vector. Transfection of pGL3 reporter vector carrying...
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