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Proteomic approach for the study of cancer cell line profiles.
Predná, Nikola ; Langová, Denisa (referee) ; Strouhalová,, Dana (advisor)
Triple-negativní karcinom prsu (TNBC), velice agresivní podtyp rakoviny prsu, je známý svou nepříznivou prognózou a omezenými možnostmi léčby. V tuto chvíli je chemoterapie považována za hlavní způsob léčby. Za účelem vyvinutí nových účinných léčiv je snaha pochopit molekulární základ této nemoci. V důsledku toho bylo již několik potenciálně aktivních látek pro tento konkrétní typ rakoviny prsu podrobeno výzkumu. V poslední době se mnoho studií zabývající touto záležitostí provádí za použití proteomiky jakožto prostředku ke studiu proteomů rakovinných buněk. Rakovinové buňky obsahují klíčové rozdíly v proteinech, které regulují mechanismy buňky. Mapování těchto mechanismů může nakonec umožnit diagnostikovat stav organismu. Tato práce se zaměřuje na proteomické studium buněk TNBC a porovnává neošetřené buňky s buňkami, které byly podrobeny léčbě retinoidy. Separace proteinů a peptidů byla úspěšně provedena elektroforézou na 1D a 2D gelu. Kromě toho byly vzorky podrobeny enzymatickému štěpení vybraných proteinů, které byly poté identifikovány pomocí hmotnostní spektrometrie MALDI-TOF (MS). Proteiny, které se podílejí na procesu epiteliálně-mezenchymálního přechodu (EMT), byly poté kvantifikovány a porovnány mezi vzorky.
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Proteomic architecture of sperm-egg interactions
Otčenášková, Tereza ; Stopka, Pavel (advisor) ; Petr, Jaroslav (referee) ; Vrbacký, Marek (referee)
Recent advances in proteomic methods provide new insights for biological research including the field of reproductive biology. Determination of the proteomic basis of spermatozoa is pivotal for understanding the complex process of gamete interactions during fertilization such as acrosome reaction. Great differences imposed by postcopulatory sexual selection and phylogeny can be observed regarding the size, shape, and molecular composition of sperm across animal taxa. The first objective of this doctoral thesis is to characterize the protein contents of the acrosome to ascertain its further functional significance in sperm-egg interaction. Also, we aim to investigate the potential relationships between sperm protein composition and sperm morphology diversification, risk of sperm competition, and species phylogenetic background. Wild-caught males from natural populations of species of Mus musculus musculus, Apodemus flavicollis, Microtus arvalis (order Rodentia), Acrocephalus palustris, Chloris chloris, Phylloscopus collybita, Cinclus cinclus, Hirundo rustica, and Taeniopygia guttata from a captive population (order Passeriformes) were subject to the analyses. Nano-liquid chromatography with tandem mass spectrometry was applied as the main methodological approach in this thesis. Our data implicate...
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Intermediate filament proteins of Preaxostyla flagellates
Švagr, Ezra ; Hampl, Vladimír (advisor) ; Varga, Vladimír (referee)
5 Abstract Monocercomonoides exilis and Paratrimastix pyriformis are protists from within the group Preaxostyla (Metamonada), they possess an excavate morphology that is presumed to be an ancestral cytoskeletal organisation of eukaryotic cells. A significant part of eukaryotic but specifically excavate morphology is fibers composed of unidentified proteins. The hypothesis on which this thesis builds upon is that these fibers are composed of Intermediate Filament proteins (IF proteins). IF proteins are a polyphyletic group of proteins involved in the assembly of mechano-elastically important fibers in eukaryotes. The most widespread group of these proteins is a family called SF-assemblins, homologues of which were identified first in Chlamydomonas reinhardii, and giardins a protein family first discovered in Giardia intestinalis, which were also found to be related to this group. Nested into the bigger hypothesis is an idea, that SF-assemblins are present in M. exilis and P. pyriformis, further strengthening their position as a universally present eukaryotic feature. The goal of this work was to find support for the morphological hypothesis that LECA possessed an excavate morphology in protein composition of the cytoskeleton. Two approaches were employed. First, identifying proteins in cytoskeletal fraction...
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Proteom rostlin v reakci na abiotický stres
Čotková, Veronika
Plants as a sessile organisms have evolved complex mechanisms to cope with unfavorable environmental conditions. This diploma thesis summarizes current state of knowledge and focuses on light, temperature and phytohormones in plant abiotic stress responses. The practical part is devoted to proteomics and completes and extends the project started during my Bachelor program. Transgenic Arabidopsis seedlings carrying inducible barley cytokinin oxidase/dehydrogenase (CaMV35S> GR> HvCKX2) were profiled to elucidate proteome-wide responses to down-regulation of cytokinin levels under heat stress at standard (80 umol.m-2.s-1) and low light intensity (20 umol.m-2.s-1). In total, 2-DE analysis and mass spectrometry analysis revealed 63 differentially abundant proteins involved in diverse metabolic processes. These data provide evidence of a link between temperature, light and cytokinin signaling in Arabidopsis and will be used in the modeling of cytokinin-light-temperature interactions.
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Isolation and characterisation of extracellular vesicles of parasitic helminths
MAZANEC, Hynek
Excretory-secretory products (ESP) serve as important mediators of intercellular and inter-species communication. They were originally thought to be secreted mainly in a soluble form, but recent discoveries indicate their delivery through extracellular vesicles (EVs). These membraneous particles provide protection from degradation for some of their components, as well as targeted delivery through various receptors on their surface. As such they have been studied as potent immunomodulators in host-pathogen relationships. With respect to parasitic helminths, EVs are being studied as agents for diagnosis, vaccination or therapeutics. However, their general biology, especially their biogenesis patterns, is still poorly understood compared to their functional role.Therefore, the goal of this thesis is to investigate in more detail the secretion activity of EVs in different tapeworms and their life-cycle stages. Under laboratory conditions, the life cycle of Schistocephalus solidus, a tapeworm with an aquatic life cycle, was established to explore EVs secretion at different developmental stages. Moreover, we used proteomic analyses and ultrastructural observations to identify the main biogenesis pathways behind EVs secretion in a terrestrial tapeworm Hymenolepis diminuta. This also allowed for the comparison of EVs generation in tapeworms with different host types.
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Integrated multi-omics analysis of chemical signaling in wild rodents
Matějková, Tereza ; Stopka, Pavel (advisor) ; Macholán, Miloš (referee) ; Bryja, Josef (referee)
Symbiotic bacteria living with the host in so-called microbiomes have been one of the significant pillars of all aspects of animal evolution, chemical communication included. However, the phenotype, genotype, and microbiome of laboratory animals kept for generations in sterile conditions changed from their wild ancestors leading to profound differences in the laboratory results and the reality of wild animals. To describe the chemical communication in neglected wild rodents, this thesis focuses on the body parts involved in chemical communication (i.e. mouth, vagina, and intestines) and are also inhabited by microbiomes that produce metabolites with the capability of transmitting chemical signals. Using next-generation sequencing and state-of-the-art proteome and metabolome chromatography-mass spectrometry, this thesis covers the analysis of changes in the microbiome, proteome, and metabolome of wild mice in the context of transferring the wild individuals into the captivity, cohousing wild, and laboratory animals and hormonal changes during the estrous cycles. Moreover, this thesis describes and discusses the differences and similarities in the microbiome, proteome, and metabolome on the level of different species (Apodemus sp.), subspecies (Mus musculus domesticus vs. musculus), and environment...
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A method for identification of foreign amylases in honey
Erban, Tomáš ; Shcherbachenko, Elena ; Talacko, Pavel ; Harant, Karel
Honey is a unique natural product. Honey has been used as a sweet and delicious foodstuff since ancient times. However, it is also valued for its multifaceted currative properties. Unfortunately, honey is one of the most adulterated foods. Nothing may be added to or modified from the honey. Honey also needs to be handled with care. Honey quality can negatively be affected by the way of processing such as heating and storage. Despite great progress in analytical methods, it is not possible to prove all adulterated honeys. Some methods of adulteration are quite sophisticated. Therefore, it is necessary find new approaches and methods for identification of honey adulteration. To be sold, honey must comply with internationally valid standards, which are also valid at national levels with possible minor modifications. One of the important parameters for honey is the level of diastase or amylase enzyme activity, which is a recognized indicator of the freshness and quality of honey. Lower diastase activity below the established level may indicate old honey, but it may also be the result of careless handling of honey. Last but not least, diastase activity may be reduced due to adulteration of honey such as its dilution with sugar substitutes. It is possible that amylase activity can be artificially adjusted by the addition of enzymes. Honey adulterated by the artificially added amylase meets the legislative requirements for placing honey on the market, but this violates the rules laid down by law. The methods used so far have not made it possible to prove this way of honey adulteration. Therefore, this methodology focuses on the identification of foreign amylases that may occur in honey. The methodology enables to identify practically any foreign amylase in honey by bottom-up shotgun proteomic approach. Based on the obtained results with specific peptides can be further used for the development of a targeted method for the identification of foreign amylases.
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Preparation of proteases for protein structure studies.
Jirečková, Barbora ; Man, Petr (advisor) ; Vaňková, Pavla (referee)
Hydrogen/deuterium exchange coupled with mass spectrometry (HDX-MS) is a method allowing the study of protein structure and dynamics. Its spatial resolution is given by the proteolysis step that is included in the HDX-MS workflow. Most widely used pepsin has however some limitations and use of a single protease often does not provide optimal spatial resolution. Several publications have emphasized the importance of the alternative proteases nepenthesin-2 (Nep-2) and aspergillopepsin (XIII) cleaving, in contrast to pepsin, after basic amino acids. In studies targeting proline-rich proteins, another enzyme, prolyl endoprotease from Aspergillus niger (AnPEP), is gaining importance. This work focuses on the characterization of immobilized AnPEP in combination with pepsin, aspergillopepsin or Nep-2 for their application in HDX-MS. First, columns with only one protease were tested on a set of model proteins. It was found that immobilized AnPEP did not have optimal cleavage characteristics compared to the other proteases. In order to combine the advantages of the proteases mentioned above, the model proteins were digested using columns with AnPEP coimmobilized with pepsin, Nep-2 or XIII and also using two protease columns in series (always AnPEP column with pepsin, Nep-2 or XIII column in both...
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Research of epigenetic aspects of hematopoietic and spermatogenesis stem cells.
Hybešová, Michaela ; Pimková, Kristýna (advisor) ; Děd, Lukáš (referee)
Stem cell differentiation is controlled by coordinated regulation of gene transcription. One of the regulatory factors is the loosening of chromatin and the accessibility of DNA to transcription factors. Chromatin remodeling is mediated by remodeling complexes. The ISWI chromatin remodeling ATPase Smarca5 (S5) is an important factor of remodeling complexes. It is a highly conserved chromatin-remodeling factor forming a catalytic subunit that can be found in several oligosubunit complexes. In these complexes, it actively regulates nucleosome structure and remodeling during DNA replication, repair and transcription. S5 has been identified as a key protein in embryonic development. Its deficiency leads to defects in hematopoiesis and male genital development. In the presented study, we focused on the role of S5 in hematopoiesis and spermatogenesis. Using a mouse model with transgenic expression of S5, co-immunoprecipitation and mass spectrometry, we identified S5 complexes in hematopoietic and testicular cells. We also studied the phenotypic consequences of S5 deficiency in mouse testes and found that it leads to impaired sperm development and male sterility. Using transcriptomic and proteomic analysis, we identified several molecular programs that could lead to reproductive disorders. Our work...
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Identification and characterization of ciliary tip proteins
Gorilák, Peter ; Varga, Vladimír (advisor) ; Lánský, Zdeněk (referee) ; Dean, Samuel (referee)
The distal tip of the cilium/flagellum, also known as the ciliary tip domain (CTD), is critical for the structure and function of the eukaryotic cilium. The limited knowledge of its protein constituents hinders a better understanding of the domain. In this thesis, we set out to verify the localization of a subset of known mammalian CTD constituents and to assess the localization of candidate CTD proteins, orthologs of which localize to the tip of the flagellum of evolutionary distant protozoan Trypanosoma brucei. Using our localization pipeline, we identified two proteins that robustly localize to the CTD of the primary cilium. One of these proteins (ZC2HC1C), in addition, also localizes to stationary foci along the axoneme, positions of which coincide with sites of intraflagellar train pausing and turning. We hypothesize that these may be ends of sub-distally terminating axonemal microtubules. We further show that the protein ULK4 localizes to the CTD of motile ependymal cilia but not to the CTD of primary cilia, consistent with previously published phenotypes in ULK4 depleted mice and exemplifying differences in the composition of CTDs of the two types of cilia. Finally, we demonstrate that Expansion microscopy, a rapid and robust super-resolution technique, is well suited for ultrastructural and...
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