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Polymorphism of TLR2/TLR1 and TLR2/TLR6 heterodimers in wild-derived house mouse inbred strains
Bainová, Zuzana ; Vinkler, Michal (advisor) ; Hyršl, Pavel (referee)
Contrary to the classical mouse inbred strains with unnatural genetic variability, wild-derived strains offer a more suitable model for evolutionary immunology. Toll-like receptors (TLRs) belong to initial detectors of invading pathogens. Although TLRs recognise conserved structures they were shown to be polymorphic. This polymorphism is associated with various diseases. In my thesis, I describe variability of Tlr1, 2 and 6 in 24 inbred strains derived from two subspecies of house mouse (Mus m. musculus and M. m. domesticus). These Tlrs exhibit different levels in variability among the strains. In Tlr1 the polymorphic sites are spread along the whole exodomain. Tlr6 is quite conserved (a lower amount of substitutions located far from the binding region and with minor modifications in the amino acid residue properties). Tlr2, on the contrary, contains some substitutions with substantial alternations of residue properties that are located within or nearby the binding region and the subspecies differ at these sites. All alleles of M. m. domesticus and M. m. musculus, except for Tlr1 PWD, Tlr2 STAIL, are phylogenetically separated. The strains and the subspecies vary in the production of IL-1β, IL-12 a NO after stimulation by TLR1, 2 and 6 ligands. This trend is, however, presumably influenced by the effect of...
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Application of Haematological Methods in Zoological Studies
Poplová, Jitka ; Vinkler, Michal (advisor) ; Krulová, Magdaléna (referee)
Haematological methods are widely used in zoological researches. Unfortunately, especially in ecological studies there is often much imperfection in techniques adopted, and misinterpretation of results is also common. This is particularly the case of methods serving to assessment of the peripheral blood cellular composition. In this thesis I therefore decided to describe basic haematological methods, their mechanisms, advantages and disadvantages. I also highlighted possible application potential in several less widely utilised haematological techniques. In the practical part of this thesis I have shown that the examination of immature erythrocyte differential count may serve as a meaningful indicator of health state in birds.
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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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Vliv polymorfismu Toll-like receptoru 4 na kondici a ornamentaci u sýkory koňadry
Bainová, Hana ; Vinkler, Michal (advisor) ; Krulová, Magdaléna (referee)
Host-parasite co-evolution belongs to the most important evolutionary relationships that shape natural and sexual selection. Parasites pose permanent selective pressure on their hosts. Toll-like receptors (TLRs) as a part of innate immunity are involved in mechanisms of a first immunological barrier which has to be overcome by parasites. These receptors play a key role in primary detection of pathogen-associated molecular patterns (PAMPs) and, hence, are responsible for early triggering of effector immunological mechanisms and for co- activating adaptive immunity. Several studies revealed that TLR4 may represent a suitable model molecule for host-parasite co-evolution studies. TLR4 interacts directly with several PAMPs and structural variability in this receptor was shown to affect host resistance to various diseases. Thus, there is potential for occurrence of parasite-mediated natural and sexual selection. Contrary to the number of fish and mammalian TLRs described, avian inter- and intraspecific TLR variability is only very insufficiently explored. This is especially true for passerine birds. In my diploma thesis I therefore provide the first description of the complete Tlr4 translated region in a non-model free-living bird, great tit (Parus major), predict structure of the protein product of...
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Vliv stavu a funkce imunitního systému na pohlavní výběr u ptáků
Vinkler, Michal ; Albrecht, Tomáš (advisor) ; Kleven, Oddmund (referee) ; Grim, Tomáš (referee)
Evolution is a most fascinating feature of all living things in our world. The means of organismal evolution are diverse, comprising mainly of natural and sexual selection. Both of these phenomena may contribute to evolutionary adaptations in health and disease. The questions of immunity impact on the process of sexual selection and sexual selection for increased anti-parasite resistance are wide issues of the present research in natural sciences. Their clarification requires multidisciplinarily-based investigation combining a variety of partial results into a single united paradigm. My co-workers and I have chosen several specific issues to study, in order to fill some of the important gaps of the current knowledge. We proposed the Carotenoid maintenance handicap hypothesis to point out that optimisation instead of maximisation of the carotenoid intake and ornamental display may be physiologically convenient for the individual. In Scarlet rosefinch (Carpodacus erythrinus) we confirmed the role of the carotenoid-based ornamental colouration in the process of sexual selection and investigated several partial aspects of the association between immunogenetics, immune function, health and the ornament expression and mate choice. In Zebra finch (Taeniopygia guttata) we have shown that the present way of...
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Evolution of molecular interaction between host and parasite
Bílková, Barbora ; Vinkler, Michal (advisor) ; Synek, Petr (referee)
Coevolution between host and parasite is a long-term object of scientific interest, mostly because of negative influence of parasites and human need to defend against it., The evidence concerning host-parasite coevolution mechanisms is, however, still incomplete and various models and theories are considered separately, out of the general concept. Beside generally well-known theories such as the "Red queen" theory or the coevolution "arms race" theory, several other models were proposed, e.g. the "gene for gene" model or the "matching allele" model, which describe detailed aspects of host-parasite coevolution and principles of genetic variability maintenance in their interaction. Although there are many studies mapping reciprocal evolution of hosts and parasites, the connection between empirical evidence and theoretical models is often missing. Therefore, this thesis covers theory on host-parasite evolutionary interactions and provides examples of host-parasite systems and molecules, which correspond to behavior of described models.
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Evolutionary implications of innate immunity receptors polymorphism
Bainová, Zuzana ; Vinkler, Michal (advisor) ; Zajícová, Alena (referee)
Interactions between hosts and their parasites are considered to be one of the major forces driving animal evolution. It can be assumed that the evolutionary changes will occur especially in host molecules directly involved in these interactions. The first line of host defense is formed by innate immunity receptors among which also pattern recognition receptors (PRRs) belong. PRRs detect the presence of parasites at the beginning of their invasion by binding characteristic structures of their bodies (so called pathogen-associated molecular patterns, PAMPs, e. g. lipopolysaccharide, flagellin or peptidoglycans) or abnormal self molecules (damage-associated molecular patterns, DAMPs, e.g heat shock proteins). Although this mechanism of immune system activation is based on the recognition of ligands that are relatively evolutionarily conservative in pathogens, growing body of evidence suggests that PRRs are highly polymorphic on both interspecific and intraspecific level. High frequencies of minority alleles can be observed in most populations studied. It has been proven that particular alleles of many PRRs may associate with increased or decreased resistance to various infectious or autoimmunity diseases. Relationship between polymorphic receptor and a disease could be the main force, which shapes the...
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Mate Choice in Scarlet Rosefinch Carpodacus erythrinus: Test of "Good Genes" and "Complementary Genes" Hypotheses
Vinkler, Michal
Master's esis, 2007 Michal Vinkler 3 I ABSTRACT Within the contemporary theory on the sexual selection there are two main competing hypotheses concerning the female indirect benefits arising from the mate choice. The 'Good genes' hypothesis assumes that the female tends to gain for her progeny some generally beneficial alleles through mating with an appropriate male. On the other hand the 'Complementary genes' hypothesis supposes that the mate choice is governed by the female effort to obtain for her offspring the most fitting parental haplotypes. This thesis aimed to provide evidence for discrimination between these two hypotheses in scarlet rosefinch. Three principal aspects of the sexual selection were concerned: (1) the reliability of male ornamentation as an indicator of individual's quality; (2) the associations between parental traits and offspring health indicators and (3) the effect of paternity on offspring heterozygosity and immune responsiveness in mixed- paternity broods. The results indicate that male ornamentation is a reliable signal of individual's health which may be used by females in their mate choice. The ornamentation does not reflect male's heterozygosity. Moreover, the social father's ornamental plumage hue and saturation are good predictors of nestlings'health and immune...
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