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Evolution of olfactory receptors
Klempt, Petr ; Stopka, Pavel (advisor) ; Vinkler, Michal (referee)
This bachelor thesis deals with the largest gene family of mammals which encode olfactory receptors. Olfactory receptors fall in rhodopsin-like GPCRs subfamily, approximately 600 - 800 millions of years old. At least from this time, olfactory receptors play, as a part of one of the oldest senses (smell), fundamental role in detection of chemical cues from water or air. This work summarizes large repertoire of olfactory receptors and its changes during the evolution of important animal taxons with emphasis on number and fraction of functional and nonfunctional olfactory receptor genes. Those values are part of criteria used for olfactory ability of animals. Olfactory receptors are typically placed on surface of sensory neuron placed in olfactory epithelium, where they bind various odorants and triggers signal cascade which leads to neuron's membrane depolarization. Therefore, about one half of this work summarizes knowledge of olfactory receptor's molecular biology like their structure, main parts of signal cascade (Gαolf, ACIII, CNG channel, Ca2+ dependent Cl- channel) just as parts needed for steady-state establishment. Expression of olfactory receptors detected in amount of non-olfactory tissues (mussels, sperm, brain etc.), indicate possibly important biomedical roles of this receptors.
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Evolution of Olfaction in Mammals with Focus on Superorder Laurasiatheria
Vondráčková, Kamila ; Hulva, Pavel (advisor) ; Hanus, Robert (referee)
The evolution history of mammals is connected with the dominance of smell and olfactory communication, which are important sense and communication channels also in recent forms. Two systems are involved in detecting and processing the molecules of scent, the main and the accessory olfactory system. These systems distinguish different types of scents, odorants and pheromones, which are also detected by different types of receptors. Significant factors for comparison of the ability of smell between mammals are both the amount of olfactory genes and the size and complexity of olfactory structures. The main emphasis in this thesis is put on the sensory part of the olfactory system and hence there is effort to support characterization of particular taxa by genomic studies. The ability of smell, respectively amount and variation of olfactory gene repertoires has been formed during the evolution on different circumstances and the ecological adaptation played a great role. The amount and diversity of olfactory receptors vary a lot in mammals and range through anosmatic Cetaceans and microsmatic bats to macrosmatic carnivores. Present thesis is focused to the superorder Laurasiatheria because of its extensive ecological differentiation and diversification of smell abilities (from anosmatic to macrosmatic...
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Evolution of olfactory receptors
Klempt, Petr ; Stopka, Pavel (advisor) ; Vinkler, Michal (referee)
This bachelor thesis deals with the largest gene family of mammals which encode olfactory receptors. Olfactory receptors fall in rhodopsin-like GPCRs subfamily, approximately 600 - 800 millions of years old. At least from this time, olfactory receptors play, as a part of one of the oldest senses (smell), fundamental role in detection of chemical cues from water or air. This work summarizes large repertoire of olfactory receptors and its changes during the evolution of important animal taxons with emphasis on number and fraction of functional and nonfunctional olfactory receptor genes. Those values are part of criteria used for olfactory ability of animals. Olfactory receptors are typically placed on surface of sensory neuron placed in olfactory epithelium, where they bind various odorants and triggers signal cascade which leads to neuron's membrane depolarization. Therefore, about one half of this work summarizes knowledge of olfactory receptor's molecular biology like their structure, main parts of signal cascade (Gαolf, ACIII, CNG channel, Ca2+ dependent Cl- channel) just as parts needed for steady-state establishment. Expression of olfactory receptors detected in amount of non-olfactory tissues (mussels, sperm, brain etc.), indicate possibly important biomedical roles of this receptors.
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