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Sexual dimorphism in the mouse olfactory system
Kuntová, Barbora ; Stopka, Pavel (advisor) ; Havlíček, Jan (referee) ; Žídek, Lukáš (referee)
Sexually dimorphic behaviour of the house mouse (Mus musculus musculus) relies on various physical and chemical cues, however, chemical signals are the most essential cues for individual recognition and in causing various priming effects on reproductive behaviour of the receiver. House mice belong to macrosmatic mammals, and thus, their sense of smell is highly developed and is able to recognize a wide spectrum of ligands from other individuals and from their surrounding environment. Volatile signals belong to organic compounds that are produced by most tissues, and may have harmfull effects on cells, and thus they are transported out of the body with lipocalin transporters where some of them may function as signals. These volatile signals are able to stimulate chemosensory neuronal receptors, and thus, yield particular responses in neural circuits. The ligand sensing has a differential effect upon males and females, however, it has not been shown yet in wild mice whether these differences are also caused by the variation in receptors and neural processing, or rather by differential expression of signals typical for each sex. The aim of this thesis was to perform comparative analysis of orofacial mucosal tissues to determine the specificity of expression of particular lipocalins. For the first time...
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Species-specific structural differences of mammalian sperm and function of their key proteins during fertilization.
Dobrodinská, Anna ; Frolíková, Michaela (advisor) ; Kuntová, Barbora (referee)
The fertilization is a process during which a male and a female gamete merge so that a new organism may come into being. The sperm-egg fusion is preceded by several essential processes, such as the capacitation, acrosome reaction, the sperm binding to the zona pellucida and oolemma, and membrane fusion of the gametes. Numerous proteins, which are located in both sperm and eggs, are major actors in controlling the listed, essential processes. During the process of fertilization these proteins fulfil one or more functions. In mammalian sperm, significant species-specific differences may be found both in their morphology and at the protein level. A complex understanding of species-specific distinctions in sperm structure and functions of key sperm proteins would contribute to a better insight into the process of fertilization, thereby enabling us to better diagnose and subsequently treat the causes of infertility in humans. This bachelor's thesis summarizes the current knowledge of sperm structure and its key proteins that has been acquired through the studies of the following model mammal species: bull, boar, mouse, and human. Further, this thesis brings an interspecific comparison between the studied species. Keywords: sperm, fertilization, acrosome reaction, capacitation, sperm proteins, bull,...
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The acrosome reaction in mammalian sperm
Picková, Jana ; Frolíková, Michaela (advisor) ; Kuntová, Barbora (referee)
The acrosome reaction (AR) of the sperm is a prerequisite for egg fertilization, which takes place in the female reproductive tract. The AR allows sperm to penetrate extracellular egg coats and fuse with the egg. At first, the sperm must undergo the process called capacitation, then AR is initiated and acrosomal content is released. While it is not clear, what initiates the AR, it is probably the egg's extracellular coats - the zona pellucida and cumulus cells, secreting progesterone and some other substances, which can initiate the AR. Lately, it was demonstrated, that in the mouse the most sperms undergo the AR in the upper isthmus of the oviduct. Only a few sperms reach the ampulla, but all of them can fertilize eggs. During the AR, the acrosomal content is released into the extracellular space. It was discovered, that the release of acrosomal proteins is not synchronous, soluble components are released faster from the acrosome than are acrosomal matrix proteins. Before the acrosomal release, G-coupled receptors and tyrosine kinase receptors activate phospholipases. Protein kinases are also activated, which results in the opening of Ca2+ channels in the acrosome and sperm plasma membrane and the release of Ca2+ . The increase of Ca2+ leads to actin depolymerization, membrane fusion, and finally,...
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Species-specific structural differences of mammalian sperm and function of their key proteins during fertilization.
Dobrodinská, Anna ; Frolíková, Michaela (advisor) ; Kuntová, Barbora (referee)
The fertilization is a process during which a male and a female gamete merge so that a new organism may come into being. The sperm-egg fusion is preceded by several essential processes, such as the capacitation, acrosome reaction, the sperm binding to the zona pellucida and oolemma, and membrane fusion of the gametes. Numerous proteins, which are located in both sperm and eggs, are major actors in controlling the listed, essential processes. During the process of fertilization these proteins fulfil one or more functions. In mammalian sperm, significant species-specific differences may be found both in their morphology and at the protein level. A complex understanding of species-specific distinctions in sperm structure and functions of key sperm proteins would contribute to a better insight into the process of fertilization, thereby enabling us to better diagnose and subsequently treat the causes of infertility in humans. This bachelor's thesis summarizes the current knowledge of sperm structure and its key proteins that has been acquired through the studies of the following model mammal species: bull, boar, mouse, and human. Further, this thesis brings an interspecific comparison between the studied species. Keywords: sperm, fertilization, acrosome reaction, capacitation, sperm proteins, bull,...
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Sexual dimorphism in the mouse olfactory system
Kuntová, Barbora ; Stopka, Pavel (advisor) ; Havlíček, Jan (referee) ; Žídek, Lukáš (referee)
Sexually dimorphic behaviour of the house mouse (Mus musculus musculus) relies on various physical and chemical cues, however, chemical signals are the most essential cues for individual recognition and in causing various priming effects on reproductive behaviour of the receiver. House mice belong to macrosmatic mammals, and thus, their sense of smell is highly developed and is able to recognize a wide spectrum of ligands from other individuals and from their surrounding environment. Volatile signals belong to organic compounds that are produced by most tissues, and may have harmfull effects on cells, and thus they are transported out of the body with lipocalin transporters where some of them may function as signals. These volatile signals are able to stimulate chemosensory neuronal receptors, and thus, yield particular responses in neural circuits. The ligand sensing has a differential effect upon males and females, however, it has not been shown yet in wild mice whether these differences are also caused by the variation in receptors and neural processing, or rather by differential expression of signals typical for each sex. The aim of this thesis was to perform comparative analysis of orofacial mucosal tissues to determine the specificity of expression of particular lipocalins. For the first time...
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