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Evolution and expression of the Odorant Binding Proteins in selected species of mice
Vinkler, David ; Stopka, Pavel (advisor) ; Trachtulec, Zdeněk (referee)
Odorant-binding proteins (OBPs) are small soluble proteins expressed at high levels in the proximity of olfactory receptors. OBPs act as solubilizers and carriers of the lipophilic odorants in the aqueous mucus of mammals and other vertebrates. OBPs have now been studied nearly thirty years, but in comparison to the wealth of data available on their structural chemistry and molecular biology, our knowledge about gene expression and function of these proteins is still insufficient. This work provides new insights into the tissue specificity of OBP and presents several new sequences of genes governing these proteins in selected species of mice.
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Sperm strategies in rodents
Šandera, Martin ; Stopka, Pavel (advisor) ; Macholán, Miloš (referee) ; Sedláček, František (referee)
Rodents exhibit diverse biology, mating systems and diverse sperm morphology. Different levels of sperm competition have therefore been found in this group. Generally, it is accepted that sperm competition in animals causes the prolongation of sperm tails. However, what other sperm morphological adaptations in rodents are affected by sperm competition? Species-specific sexual selection likely optimizes sperm morphology. Sperm physiology, morphology and competition may be influenced, ultimately, by environmental factors. This Ph.D. thesis focuses on sperm competition in murine rodents. The thesis contains three research articles (including one as a submitted manuscript). In addition, another published article, partialy related to the topic of this thesis, is represented in the Appendix. The sperm morphology in rodents plays an important role in sperm competition. Longer tails and apical hooks are usually found in the species with relatively larger testes and with higher percentage of multiple paternity (i.e. rate of promiscuity), that is in species with the higher risk of sperm competition. The goal of the first study was to investigate the relationships between relative testis weight and sperm traits (apical hook and tail lengths and variance in this traits). The apical hook length was positively...
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Strategie mateřské investice u modelového monotokního a polytokního savce z pohledu životní historie
Dušek, Adam ; Stopka, Pavel (advisor) ; Šumbera, Radim (referee) ; Tkadlec, Emil (referee)
The litter size is one of the most important determinants of mammalian life-histories. Depending on the size of the litter, the mammals can be divided into two main groups: (1) the monotocous mammals, producing only one offspring per litter; and (2) the polytocous mammals, producing more than one offspring per litter. This life-history dichotomy entails different strategies whereby the mammalian females may optimize their maternal investment. The aim of this Ph.D. thesis is to show variation in the maternal investment strategies of monotocous and polytocous mammals from a life-history perspective. In order to address this issue, I investigated the strategy of maternal investment in the red deer (Cervus elaphus), representing a typical monotocous mammal, and the house mouse (Mus musculus), representing a typical polytocous mammal. From a life-history perspective, the red deer, producing no more than one litter per year, can be viewed as a model of "K-selected species", while the house mouse, producing up to ten litters per year, can be viewed as a model of "r- selected species". The red deer and the house mouse are ideal model organisms for this type of research also because they both are representatives of the most common mammalian mating system - the simultaneous polygyny. A general assumption of...
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Territoriality and social relationships in field mice of the genus Apodemus
Cholevová, Kristýna ; Stopka, Pavel (advisor) ; Vohralík, Vladimír (referee)
1 Territoriality is a phenomenon associated with resource use and social system in animals. This phenomenon reached the highest level in birds (Aves) and mammals (Mammalia). Wood mice (Apodemus) can be a good genus for research. Due to that they are abundant and well studied, they can be used for checking existing knowledge of territories, social relationships and reproductive strategies. Differences in ecology between species can help us investigate a lot of phenomena, including the phenomenon sometimes called monogamy-polygyny shift, using comparative studies.
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Chemical communication in field mice of the genus ApodemusApodemus
Obstová, Lucie ; Stopka, Pavel (advisor) ; Vohralík, Vladimír (referee)
The bachelor thesis deals with a special sebaceous organ that probably serves as a chemical communication means with four species of Apodemus field mouse - A. flavicollis, A. sylvaticus, A. agrarius and A. microps. This organ is found on the ventral side of a tail, so it is classified as a caudal organ. It consists of significantly enlarged sebaceous glands. It is particularly developed mainly with males; however, both females and infants have it as well. Its morphological structure has the same base regardless of the species, gender, and/or age; however the extent of development varies among species. The organ releases a secretion whose chemical content is unknown so far. Thanks to the gas-liquid chromatography, researchers have found out that there are both variations in the secretion contents among individual species, as well as within the same species. This kind of secretion is basically a characteristic feature of an individual, as it bears information about the species, gender, age and even the population affiliation. Functions of the organ stay unknown as well. It might serve to mark the territory, to play a role in social interactions (i.e. agonistic behaviour) and/or to be an important part of copulatory behaviour.
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Study of chemical communication in the house mouse: a proteomic approach
Janotová, Kateřina ; Stopka, Pavel (advisor) ; Piálek, Jaroslav (referee) ; Vošlajerová, Barbora (referee)
Chemical communication of the house mouse is similarly as in other mammals, substantially complex and influence every social ineraction between individuals. Important part of mouse chemical signalling system is Major Urinary Protein complex (MUP). These proteins are known as pheromone-carriers that prolong longevity of the pheromones by retarding their evaporation from the scent mark. Their other role in chemical communication is direct signalling which is mediated by VNO. MUP have been shown to trigger both behavioural and physiological effects in recipient. Proteins belonging to the same family (lipocalins) as MUPs, have been found in other, mainly rodent, species. Although the information about these urinary lipocalins are, with exception of mouse, very limited, it is likely that their roles relies in chemical communication. The Ph.D. thesis is related to the urinary proteins in the house mouse and Mastomys coucha. Thesis contains four chapters represented by three published and one submitted manuscript. One aim of the thesis is to provide information about these proteins in the subspecies Mus musculus musculus which is widespread in the Czech Republic and which is much less studied when compared to Mus musculus domesticus. The part of Ph.D thesis is a review publication which summarizes recent...
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The role of Toxoplasma gondii on the expression of Major Urinary Proteins in the house mouse
Hladovcová, Denisa ; Stopka, Pavel (advisor) ; Hrdý, Ivan (referee)
Major Urinary Proteins (MUP) are pheromonal transmitters involved in chemical communication in rodents. Complexes of MUPs and ligands mediate information about genetical background of an individual and co-create individual scent profile. They play a significant role in kinship determination, the crucial factor in the choice of a mating partner. It is assumed that the MUP production is energetically demanding due to the pressure of sexual selection, and the transmitted signal is thus supposed to be honest. This theory hasn't yet been experimentally tested, neither was proven the effect of another intense selection pressure- a parasitic infection. In my thesis, I describe the effect of an infection of a parasite Toxoplasma gondii on MUP production. The results suggest that the production is altered in both sexes, the production decreasing in males to the level of male castrates (or the female level). Considering the results of more detailed analysis of the infection we assume that the energetical demands of the MUP production doesn't allow the production of ordinary amounts if MUPs during the first phase of the infection as the energy is primarily devoted to the infection control. The increased production in latter phase can be attributed to the importance of scent communication. Decreased levels of...
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Analysis of gene expression during spermatogenesis in mice
Suchan, Jan ; Stopka, Pavel (advisor) ; Hortová, Kateřina (referee)
Spermatogenesis is very unique and complex process regulating and be amenable to reproductive behaviour equally. These processes are affected by outer factors such as social stimuli, represented by interaction between male and female. Mice belong to mammals with high sensitivity to chemical signals. Hence pheromonal communication takes important part in their life. Pheromones have effect on expression activity in testicular tissue throught hormonal pathways. A target of these regulations are for example proteins participating in immunity or competition actions. Phenotype plasticity might proceed on the level of DNA as well as on the level of gene expression. That's why we take interest if factors like social contacts are able to significantly change expression of genes involved in reproduction pathways. We are also interested in possibility that expression changes of target genes take part in speciation events. In this study we demonstrate the effect of short-term social contact to gene expression of biochemical pathways involved in spermatogenesis and by other pathways linked together with reproductive bahaviour. This involvement might be direct or indirect. We found genes, whose level of expression in testicular tissue is different between species Mus m. musculus and Mus m. domesticus. Here I provide...
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