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Geographical variation of localisation in vertebrates
Cinerová, Michaela ; Petrusková, Tereza (advisor) ; Turčoková, Lucia (referee)
Sound expressing is common for a big amount of animal species, mostly when communicating with individuals of their own or other species. Acoustic communication can be used especially in situations or in the environment where an individual does not see a signal receiver well (confusing environment, at night or long distance). It's well-known that the individual species have their own characteristic acoustic expressions. However, these can differ also within the species itself, either in time or in space. This study is concerned just with variability of inter-species vocal communication of all vertebrates in space. Its purpose is to map at which animal species vocalization vary in space. Furthermore, it deals with searching for causes of origin of this variability, such as genetic differences among particular groups of populations, environmental and learning effects etc. within various animal species. In the last part, it tries to answer the question whether the spatial variability of acoustic signals could influence separation of new species and thus have evolutionary consequences.
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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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Regeneration of heart muscle in vertebrates
Bergelová, Barbora ; Krylov, Vladimír (advisor) ; Mašek, Jan (referee)
Fish model organisms such a Danio rerio have the ability to regenerate heart muscle during its whole lifespan. Compared to Danio rerio, the ability of heart regeneration differs in amphibians. While the newt has the ability to regenerate its heart tissue throughout its whole life, the Xenopus leavis loses its power when it goes through metamorphosis. The regenerative ability varies not only between genera but also between species. For example compared to Xenopus leavis, Xenopus tropicalis has the ability to regenerate its heart tissue even in adulthood. Mammals have a very limited ability to regenerate their heart muscle. We can observe the ability to regenerate heart after injury in mice and humans for a very limited time of a few days after birth. In adulhood the heart is healed via rich collagen scar. It is vital that signaling pathways in highly regenerative model organisms are intensively studied, so that the knowledge gained may help us in the treatment of heart injuries in humans. Key words: regeneration, heart muscle, repair, zebrafish, mammals, amphibians, heart development, vertebrates
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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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Regeneration abilities among vertebrates
Majerová, Veronika ; Starostová, Zuzana (advisor) ; Soukup, Vladimír (referee)
Among vertebrates the ability to regenerate various body structure, from the cellular level to diverse internal organs or even the complex body structures (such as limb or tail), is unequally distributed across animal taxa. Regeneration is understood as the restoration of damaged or completely lost tissues, while the restored structure is more or less similar or even identical to the original structure. Regeneration is naturally often preceded by an encounter with a predator, when the animal is directly injured by the predator or an autotomy may occur as an anti-predator mechanism, which means that the animal voluntarily releases an appendage. Autotomy and following regeneration have many advantages but there can also appear some costs associated with these events which may have various consequences Masters in regeneration are considered to be mainly urodele amphibians who are able to perfectly regenerate various body structures (such as eye lens, limb or tail) and this ability persists throughout their lives, unlike anuran amphibians, in which the ability to regenerate after metamorphosis decreases significantly. In contrast to amphibians, the ability to regenerate among mammals or birds is severely limited. The aim of this work is to approach the ability of regeneration and the mechanisms by...
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Mortality of small animals on singletrails in Marianské údolí valley (Brno, Czech Republic)
Homolka, Miloslav ; Mikulka, O. ; Kamler, J. ; Drimaj, J. ; Plhal, R.
Singletrail areas became a part of tourist business all over the world. Cycling routes usually go through the natural environment, they are used especially in the summer and therefore are quite evident that small animals are killed on them. The submitted contribution indicates what effects have the traffic on the singletrail on small animals in the deciduous forest environment (Brno, Czech Republic). During singletrail traffic insects and small vertebrates were killed. The number of cadavers of individual species was relatively small on the trails (3800 individuals of insect and 51 of vertebrates one during 3 months on the 11 km of the route) and traffic most probably does not endanger the existence of any animal species at the local population level. Mostly the common species were perished on the trails, but individuals of specially protected and endangered species were also killed there (Calosoma sycophanta, Bombus spp., Anguis fragilis, Bufo bufo) so this fact should not be overlooked and underestimated. For ethical and educational reasons, the construction of new singletrail areas should be preceded by careful research of particular area in order to map the distribution of small animals and choose the route with regard to minimizing mortality, especially endangered species of fauna.
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Regeneration of heart muscle in vertebrates
Bergelová, Barbora ; Krylov, Vladimír (advisor) ; Mašek, Jan (referee)
The model organisms like for example the fish Danio rerio has the ability to regenerate heart muscle during its whole lifespan. Compared to Danio rerio, the ability of heart regeneration differs in amphibians. While the newt has the ability to regenerate its heart tissue throughout its whole life, the Xenopus leavis loses its power when it goes through metamorphosis. The regenerative ability does not only differ between salamanders and claws. We can observe some differences between regeneration of Xenopus tropicalis and Xenopus leavis too. Compared to Xenopus leavis, Xenopus tropicalis has the ability to regenerate its heart tissue even in adulthood. Mammals have a very limited ability to regenerate their heart muscle. We can observe the ability to reverse heart damage in mice and humans for a very limited time of a few days after they are born. In adulhood they repair the heart muscle and the rich collagen scar is formed. It is vital that signaling pathways in regeneration of model organisms is researched further, so that the knowledge gained may help us in the treatment of heart injuries in humans. Key words: regeneration, heart muscle, repair, zebrafish, mammals, amphibians, heart development, vertebrates
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Comparative development & evolution of adenohypophysis in vertebrates
Brezarová, Dominika ; Černý, Robert (advisor) ; Kozmikova, Iryna (referee)
Adenohypophysis is very important gland in vertebrate head. In general adenohypophysal development is described together with formation of the primary mouth. Adenohypophyseal placode migrates together with stomodeal placode in ventral direction. Stomodeal placode starts to invaginate and from oral ectoderm adenohyphyseal placode invaginates to form Rathke's pouch. Pouch is then separated from mouth and migrates towards the brain to make adult hypohyseal gland. Origin of adenohypophysis is therefore in oral ectoderm, but in some vertebrates species is this development little different and adenohypophysis can even be endodermal. In some vertebrate groups, like amphibians or fishes there's no sign of Rathke's pouch, thus early migrations of adenohypophyseal placode can be different. These differences are there maybe because these groups don't have shallow invagination of stomodeum like other vertebrates. There are some homological structures in other chordate groups, for example Hatshek's pit in amphioxus or neural gland in tunicates, these structures has, in contrast with vertebrates, endodermal origin. Key words: adenohypohysis, placodes, primary mouth, craniofacial development, Rathke's pouch, vertebrates
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Shared mechanisms of development of vertebrate body appendages
Vintr, Jan ; Soukup, Vladimír (advisor) ; Krylov, Vladimír (referee)
Vertebrate body appendages include a number of structures such as limbs, paired and median fins, the tail bud, the cloacal region, barbels or pharyngeal arch derivatives. Despite differences in form and function, these appendages share a number of developmental genetic mechanisms. Development of these structures is chiefly regulated by Fgf, Shh, Wnt, Tgf-β and retinoic acid signalling pathways, activity of transcription factors such as Hox or Tbx along with cis-regulatory elements controlling the genes in which these factors are encoded. A recurring feature shared by some of the herein discussed anatomical structures is a transient epithelial ridge whose activity influences production and proliferation of the adjacent mesenchyme. Some are also instructed by a signalling centre, which confers asymmetry to the structure. In this text, the various appendages are compared on the basis of their development in relation to tetrapod limbs and theories evaluating the emergence of vertebrate paired appendages. The fin fold theory and archipterygial theory are discussed in the light of recent data provided by evolutionary developmental biology. All together, this thesis evaluates shared and derived characteristics of vertebrate body appendages with the aim to provide a basis for the upcoming work on the role...
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The embryonic development of the pharyngeal region in vertebrates
Píchová, Lenka ; Černý, Robert (advisor) ; Minařík, Martin (referee)
The fully-formed pharynx is for adult vertebrates indeed a vital structure. The pharynx provides two main functions - dealing with food and breathing. During embryonic development, pharynx is visible like a series of bulges on the lateral surface of the head. Embryonic development of the pharyngeal region starts with evagination of the endoderm to form the pouches, opposit to that the ectoderm invaginates to form the ectodermal clefts. Pharyngeal arches are formed after fusion of these epithelial layers, and pharynx is thus bordered by ectoderm from the inner, and endoderm from the outer side. Each pharyngeal arch consists of mesenchymal core of mesodermal and neural crest derived cells. All vertebrates develop through the so called phylotypic stage, being represented by the - pharyngula with the present pharyngeal arches. Accordingly, it was generally believed that development of the pharyngeal region is rather conservative in all vertebrates. My comparative analysis of pharyngeal development in different vertebrates species reveals that - only early embryonic formation of pharyngeal arches seems conserved, however, that later in development pharyngeal arches form various and diverse derivatives. Key words: Vertebrates, ectodermal fleft, endodermal pouch, pharyngeal arches, neural crest
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