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The role of cytoskeleton in cell chirality
Jandjuková, Anna ; Libusová, Lenka (advisor) ; Soukup, Vladimír (referee)
The cytoskeleton is one of the key structures inside the cell. The cytoskeleton includes microfilaments, microtubules, intermediate filaments, and more recently, septins. Cytoskeletal proteins play a role in intracellular transport, cell movement, cell division, and other structural functions. A chiral object is one that is not identical to its mirror image. The concept of chirality is most commonly used to describe chemical molecules. Cells of living organisms are composed of molecules, most of which are chiral. In recent years, cellular chirality has been observed, likely involving the cytoskeleton. Cellular chirality refers to the cell shape, organelle positioning, stable cell movement and directionally biased growth of cell culture. The latest findings suggest a probable influence of cell chirality on the development of right-left asymmetry during the embryonic development of animals. This work summarizes current knowledge regarding the role of the cytoskeleton in establishing cellular chirality and its likely connection to the development of right-left asymmetry during embryonic development. Key words Cell chirality, cytoskeleton, embryonal development
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Regulation of the regular distribution of body covering structures
Zbirovský, Richard ; Soukup, Vladimír (advisor) ; Brejcha, Jindřich (referee)
5 Abstract Vertebrates are characterised by a great diversity of integumentary appendages, such as scales, feathers or hairs, or modifications derived from them. These organs tend to be distributed individually and evenly across the body surface, and the degree of regularity of their organisation may vary between species. The regulation of their formation and regular distribution is determined by epithelial-mesenchymal interactions. Signaling pathways are key components of these interactions, and molecular morphogens such as BMPs, Wnts, FGFs and Shh are their frequent participants. Many mathematical models have been proposed in an attempt to explain the relationships between those morphogens, which lead to the orderly spacing of integumentary appendages, during the process that is also known as patterning. Recently, however, the Turing reaction-diffusion model, consisting of the interplay between activators and inhibitors to achieve a self-organizing, repetitive patterning, has come to the fore again. The aim of this Bachelor thesis is to further explore the role of the Turing mechanism in the regulation and regularity of the distribution of body covering organs. Keywords: vertebrates, Turing, reaction-diffusion mechanism, patterning, feathers, hairs, scales, FGF, BMP, Shh, Wnt
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Bombing of Protectorate territory by Allied troops in 1945 in the context of ideological struggle in 1945-2015
Soukup, Vladimír ; Šedivý, Ivan (advisor) ; Michela, Miroslav (referee)
SOUKUP, Vladimir: Bombing of Protectorate territory by Allied troops in 1945 in the context of the post-war ideological struggle in 1945-2015. [Bachelor thesis]. - Charles University in Prague. Faculty of Philosophy: Institute of Czech History. - Head of work: Prof. PhDr. Ivan Šedivý CSc. Level of professional qualification: Bachelor. Prague FFUK, 2023. The aim of this final work is to map the view of the period media on the Allied air raids of 1945, carried out by Soviet and American bombers on the territory of the Protectorate of Bohemia and Moray and then to compel its transformation into socialist and post-socialist era. The work consists of 7 chapters in total, with the first devoted to the premise for the emergence of ideological-information warfare in subsequent periods, the seventh dedicated to summarizing the findings on the case of Hrotovice. The other 5 chapters then analyze the content of the articles and their interpretation during the socialist era in Czechoslovakia and the post-socialist era in the Czech Republic.
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Left-right asymmetry specification in vertebrates
Vrúbel, Matěj ; Soukup, Vladimír (advisor) ; Fabian, Peter (referee)
The left-right body axis, along with the dorso-ventral and antero-posterior axis, is certainly very important, but at the same time the most neglected body axis of bilaterally symmetrical animals. The asymmetrical distribution of visceral organs along this body axis is vital for many animals. In vertebrates, this asymmetry becomes established at early embryonic stages. An essential role in this process is played by the organizer, which is responsible for the correct establishment of the left-right axis. Among vertebrates, organizers of left-right asymmetry are found in different parts of the embryonic body, and with few exceptions, they are composed of cells with motile cilia, which create an unidirectional leftward flow of extracellular fluids in the organizer. The flow is probably sensed by the cells that surround the left side of the organizer. These cells respond to the aforementioned mechanical stimulus by triggering the Nodal signaling pathway. This signaling cascade results in the left-sided expression of the Pitx2 gene, which specifies the left side of the embryonic body. It appears, that the role of Nodal signaling pathway in determining left-right asymmetry is not only present in all vertebrates, but also is probably ancestral to bilaterally symmetrical animals. Another mechanism ensuring...
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Left-right organizer of body asymmetries in ray-finned fishes
Kupková, Anežka ; Soukup, Vladimír (advisor) ; Krylov, Vladimír (referee)
Left-right asymmetry of the body occurs across a number of organisms from invertebrates to vertebrates, and is mostly exhibited by the asymmetry of internal organs. These asymmetries are established at early stages of embryonic development due to the action of temporary structures called organizers of left-right asymmetry. In ray-finned fishes, the most-studied organizer is the so-called Kupffer's vesicle present in the teleosts. It is a hollow structure composed of monociliary cells. The cilia of these cells rotate and generate a leftward flow of extracellular fluid. The flow subsequently triggers the induction of the Nodal signalling cascade, which is responsible for left-right organ orientation and is considered evolutionarily conserved in vertebrates. The main participants in this pathway are the Nodal, Pitx2 and Lefty factors. In contrast to teleosts, the left-right organiser of non-teleost ray-finned fishes resembles the gastrocoel roof plate present in amphibians, which is apparently ancestral for ray-finned fishes. This bachelor thesis evaluates the origin and function of Kupffer's vesicle, describes the Nodal signalling cascade triggered by this organizer, and compares Kupffer's vesicle with the organizer of non-teleost ray-finned fishes.
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The role of nitric oxide (NO) during Xenopus laevis embryonic epidermis development
Tománková, Silvie ; Šindelka, Radek (advisor) ; Krylov, Vladimír (referee) ; Soukup, Vladimír (referee)
Nitric oxide (NO) is an interesting molecule, which is involved in many important biological processes such as vasodilatation, neurotransmission, immune response and cell proliferation. This work presents the crucial role of NO during the Xenopus laevis embryonic epidermis development. The outer layer of the embryonic epidermis is composed of 4 cell types (small secretory cells, multi-ciliated cells, ionocytes and goblet cells). Embryonic epidermis composition reflects specialized epithelia such as a respiratory epithelium of mammals. Therefore, Xenopus embryonic epidermis has become a suitable model for the study of human mucosal and mucociliary epithelium and their defects. I found that NO is mainly produced in ionocytes and multi-ciliated cells by using molecular and immunohistochemical approaches. The study of molecular and cellular phenotype changes in embryos with inhibited NO production revealed the necessity of this molecule for correct formation and function of the mucociliary epithelium. NO inhibition caused reduction of specialized epidermal cell types (small secretory cells, ionocytes and multi-ciliated cells) and structural changes in multi-ciliated cells. I also showed that NO affects the development of the embryonic epidermis through the sGC-cGMP-PKG signaling pathway, probably by...
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Postnatal Ontogenesis of the Skull of the Pond Slider Turtle (Trachemys scripta)
Čtrnáctová, Lenka ; Brejcha, Jindřich (advisor) ; Soukup, Vladimír (referee)
This thesis focuses on the descriptive analysis of skull morphology of the pond slider turtle (Trachemys scripta elegans). The general approach was an osteological preparation of the skulls and photographic documentation (following standardised procedures) of a larger sample of specimens. The collected data was used as a background for subsequent GMM analyses. Main hypotheses of this project were: 1) the skull of T. s. elegans is sexually dimorphic; 2) the skull of T. s. elegans constitutes of several independent modules. The objective of this thesis was therefore to describe the postnatal ontogenesis of the model taxon and to determine the developmental trends of its cranial structures. It was shown that the skull of T. s. elegans is sexually dimorphic in shape mainly due to differences in allometric growth. These differences probably reflect different nutritional requirements. The skull of T. s. elegans is formed out of four modules. These are: facial, central, basicranial, and possibly also zygomatic-pterygoideal modules.
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Molecular mechanisms of vertebrate limb regeneration
Onhajzer, Jakub ; Krylov, Vladimír (advisor) ; Soukup, Vladimír (referee)
Limb regeneration fascinates innumerable scientists for decades. Urodele amphibians can regenerate their limbs perfectly. This ability is preserved for a whole lifetime. However, they are not the only ones who regenerate their limbs. Second species are anuran amphibians, but their ability to promote limb regeneration take place only throughout a larval stage. Both groups belong to amphibians. Limbs are regeneated by the process called epimorphosis. The primary process is formation of blastema, mass of heterogeneous dedifferetiated cells, which are unipotent with the capacity to redifferentiate into only one cell type. Essential factor is the regulation of limb regeneration by numerous molecular mechanisms in order to achieve the perfect limb shape, without unwanted tumors. Mechanisms allowing limb regeneration in lower vertebrates would be applied via regenerative medicine in higher vertebrates in the future. Keywords: regeneration, limb, epimorphosis, dedifferentiation, vertebrates
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Development and dynamics of the palatal and pharyngeal dentition in sterlet
Novotná, Štěpánka ; Soukup, Vladimír (advisor) ; Oralová, Veronika (referee)
Dentition is a key vertebrate innovation showing not only great morphological diversity, but also different maintenance or replacement of functional teeth. Most extant vertebrates replace their dentition through addition of new teeth from deeply invaginated epithelium, i.e. the successional dental lamina, due to presence of dental stem cells. However, in some early branching lineages of ray-finned fishes (Actinopterygii), new tooth germs arise from the adjacent superficial epithelium without the presence of the successional dental lamina. Whether the two types of dental development in vertebrates are equivalent and whether comparable dental stem cells play role in tooth replacement is currently not satisfactorily evaluated. This Master thesis aims at describing the development of palatal and pharyngeal dentition of a member of an early branching lineage of ray-finned fishes, the sterlet sturgeon (Acipenser ruthenus). The sterlet dentition is fairly dynamic. The teeth are replaced without the successional dental lamina, however, this replacement shows characteristics similar to those described in vertebrates with the successional dental lamina. A marker of dental stem/progenitor cells, Sox2, is localized in the outer dental epithelium of the predecessor tooth in the vicinity of the adjacent taste...
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Antero-posterior polarization of body appendages in vertebrates
Smlsal, Dan ; Soukup, Vladimír (advisor) ; Krylov, Vladimír (referee)
Body appendages of vertebrates are structures developing during embryonal stages through lateral outgrowth from main body axis. Despite their different composition and high diversity, all these structures are organised along three main axes. Antero-posterior polarization is the most significant in body appendage differentiation. These polarized differentiation changes are best understood in the limbs, where they are controlled by the organizing centre named zone of polarizing activity (ZPA). This centre interacts with another centre named apical ectodermal ridge (AER), which mainly governs limb outgrowth laterally from the body axis. ZPA produces Sonic hedgehog (Shh), along with other signalling molecules participating in the polarization. Shh is a key part of highly conserved signalling pathway common to polarized structures and is influenced by retinoic acid (RA), which plays role in the ZPA creation. ZPA activity stimulates secretion of fibroblast growth factors (Fgf) and bone morphogenic proteins (Bmp). All these signalling pathways ensure correct differentiation of appendages through interaction and concentration-dependent mechanisms. The goal of this thesis is to introduce the mechanisms of polarization in other appendages, such as external genitalia and branchial arch derivates to the reader,...
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