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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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Fc receptor-like molecules: biological role and phylogenetic conservation of FcRL multigene family
Böhmová, Helena ; Komrsková, Kateřina (advisor) ; Vinkler, Michal (referee)
Fc receptor-like (FcRL) molecules are novel immunological receptors with intriguing proposed roles in the immune system. Phylogenetic studies revealed that FcRL genes are conserved in jawed vertebrates (Gnathostomata), and likely formed during adaptive system genesis. FcRLs have multiple extracellular immunoglobulin domains, and some representatives have newly documented specific ligands. Several FcRLs contain both ITIM and ITAM cytoplasmatic sequences, which provide them with dual signalling properties. These allow them to regulate intracellular signalling pathways. FcRLs are known to engage in B cell regulation. They are largely expressed on B cells, with some representatives preferentially expressed on cytotoxic T cells and NK cells. Their expression patterns are specific to distinct B cell subpopulations and also show different levels of expression during B cell differentiation, pointing to their possible involvement in this process. FcRL molecules have also been detected on the mammalian eggs, and they may potentially play role in gamete fusion. This thesis aims to introduce FcRL molecules in various aspects, including their relation to classical Fc receptors, their structural properties, genomic organisation, phylogenetic conservation and their roles in organism. Thesis also focuses on...
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Inflammation-associated changes in cannabinoid receptor expression in avian brain
Divín, Daniel ; Vinkler, Michal (advisor) ; Bendová, Zdeňka (referee)
(EN) Research in interactions between the nervous and immune systems is focused mainly on mammals, while in other vertebrates, including birds, it remains neglected. Two types of cannabinoid receptors interconnect the nervous and immune systems: CB1, which is in mammals involved in regulation of neural processes, and CB2, which is in mammals involved in regulation of immune processes. However, little is presently known about the roles of these receptors in nervous and especially immune processes in birds. Therefore, in this work I focus on the expression of cannabinoid receptors in cognitively advanced bird species (parrots, passerines) during induced sterile peritoneal inflammation. Unlike passerines, parrots appear to lack the gene for CB2, which may affect the inflammation regulation. I have revealed no changes in the expression of these receptors during peritoneal inflammation neither in parrots, nor in songbirds. Nevertheless, the increase in expression of the proinflammatory cytokine IL- 1β in the brain in parrots confirms the importance of neuroimmune interaction and mutual influences along the gut-brain axis. This work suggests that even in birds, the central nervous system is affected by inflammation through the gut-brain axis. The expression of cannabinoid receptors does not change much...
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Adaptive evolution of Toll-like receptors in birds
Velová, Hana ; Vinkler, Michal (advisor) ; Elleder, Daniel (referee) ; Novák, Karel (referee)
Adaptive evolution of Toll-like receptors in birds Hana Velová, PhD thesis 6 Abstract Toll-like receptors (TLRs) are one of the key and presumably also evolutionary most original components of animal immune system. As Pattern recognition receptors they form the first line of innate immune defence against various pathogens. The proper receptor binding of pathogenic ligands is crucial for their correct recognition and for subsequent triggering of an appropriate immune response. Because there exists a direct interaction between the receptor surface and the pathogenic ligand, host-pathogen coevolution on molecular level can be predicted. Thus, through variability of their ligands, TLRs are exposed to extensive selective pressures that may be detected on both genetic and protein levels. Surprisingly, the variability we revealed in birds is even higher than previously expected based on the reports from other vertebrates, mainly mammals. In my doctoral thesis I summarise the results of my contribution to the avian TLR research. We were the first who experimentally verify the absence of functional TLR5 in several avian species and duplication of TLR7 in others. We finally resolved the origin of duplication in TLR1 and in TLR2 family. An important part of my research project focused on the prediction of potentially...
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Trans-species polymorphism in selected innate immunity genes in tits (Paridae family)
Těšický, Martin ; Vinkler, Michal (advisor) ; Štefka, Jan (referee)
Adaptation of host receptor system to optimal detection of infection-related structures is one of the key evolutionary challenges of immunity in host-pathogen interactions. Toll-like receptors (TLRs) are genetically variable molecules of vertebrate innate immunity that recognise danger signals, e.g. pathogenic molecules. Examination of genetic variation in TLRs may reveal mechanisms of host immunity adaptation to pathogenic pressure at molecular level. Trans-species polymorphism (TSP) is a phenomenon which assumes that several identical alleles or allelic lineages are inherited from ascendant to descendant species and these may be subsequently maintained over a long period of time in a polymorphic state. Whereas in adaptive immune genes the concept of TSP is well understood, little is presently known about TSP in innate immune genes such as TLRs. In this thesis I describe genetic polymorphism in functionally-relevant regions of TLR4 and TLR5 in 192 individuals representing 20 species Paridae family (tits, chickadees and titmice). These two receptors bind mainly bacterial ligands (TLR4 detects lipopolysaccharide and TLR5 detects flagellin), being among the first ones to trigger immune response to bacterial pathogens. To differentiate presumed TSP from gene flow among species, intron sequences of six...
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Variability in selected haematological traits related to gastrointestinal microbiota in parrots (Psittaciformes)
Dlugošová, Sylvie ; Vinkler, Michal (advisor) ; Volf, Jiří (referee)
Thousands of parrots all over the world suffer from illnesses and medical complications that can result from interactions between their immune system and bacteria in their digestive tract. The aim of this master's thesis is to understand the link between symptoms of these medical issues, the composition of blood and gastrointestinal microbiota in parrots. Using the hematological methods, 198 blood samples representing 53 parrot species were analyzed. The composition of microbiome was defined by combination of a molecular approach using bacterial 16S rRNA gene sequencing in 132 fecal samples, 12 intestine samples, 228 cloacal swabs and 236 beak swabs representing in total 61 parrot species and a diagnostic approach by psittacine fecal Gram's stain method. Significant association of hematological parameters with individual, environmental and clinical factors was observed, as well as its considerable interspecific variability. Absolute heterophile and lymphocyte counts have been shown more useful for infectious and autoimmune disease monitoring than H/L ratio. Relative numbers of basophiles were the best indicator for behavioral disorders. In relation to hematological parameters, the effect of the bacterial family Flavobacteriaceae, as part of the oral microbiota, and the bacteria Escherichia or...
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Effect of ageing on haematological and immunological traits in great tit (Parus major)
Krajzingrová, Tereza ; Vinkler, Michal (advisor) ; Remeš, Vladimír (referee)
v III. Abstract (EN) According to the Disposable soma theory, senescence is mainly influenced by adaptive allocation of resources among the physical growth, reproduction and self-maintaining processes, which depend on expected survival of an individual. The amount of allocated resources may be influenced by external environmental factors such as heavy metal pollution or by inner factor e.g. reproduction. The aim of my diploma thesis was to clarify the relationships between senescence, selected haematological traits, reproduction and efficiency of innate immunity mechanism. Moreover, we are interested in the role of heavy metal pollution in ageing and haematology. The heterophiles to lymphocytes ratio (H/L) was used as a marker of long-term stress caused by these physiological expenses. This study summarizes partial data collected within the long-term research of great tits (Parus major) in Prague, Czech Republic, I participated in. We have more than 300 samples of repeatedly captured individuals at our disposal. The structure of this unique dataset allows us to observe changes in the traits of our interest during an avian lifespan. Our results show that during aging, males experience a noticeable increase in the H/L ratio compared to females. Although we have not found the effect of age on the brood size,...
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Influence of anthropogenic pollution by heavy metals on freshwater invertebrates
Varvažovská, Adéla ; Tropek, Robert (advisor) ; Vinkler, Michal (referee)
This bachelor thesis summarizes the effects of heavy metals on freshwater invertebrates in post- industrial areas. There are heavy metals of dual origin in nature, essential and non-essential. Non-essential heavy metals which get to nature by human activities can have a negative impact on lives of organisms in the ecosystem. If the organisms can't cope with and adapt to heavy metals, it can be lethal for them. Some organisms are more tolerant than others and can survive in heavy metal concentrations which would be a big fatal to other organisms. In case of dangerous concentration for more resistant species, the resistant species create special adaptations which help them survive and prosper in the polluted areas. Mechanisms and adaptations that prevent the body from damaging cell structures and organs in the body can be of different nature. Morphological changes consist of changing the color, shape of the body or removing parts where heavy metals accumulate. Physiological mechanisms help to modify the metabolism and mode of accumulation of substances in the body. Many mechanisms, as well as the consequences of heavy metals, can be used to bioindicate polluted waters. Such observation can then be used in other disciplines, for exampl in environmental protection. Study of documents from professional...
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Evolution of immune response driven by increasing pathogen virulence
Hančová, Klára ; Vinkler, Michal (advisor) ; Macháček, Tomáš (referee)
Coevolution is relationship between two or more species reciprocally affect each other's evolution. Coevolution is also known as host-parasite interaction where parasite becomes the driving force of host evolution. In an effort to escape the parasite, hosts create different mechanisms that protect themself from infection or minimize its impact. This text is written to acquaint the reader with the host-parasite interaction in response to improving parasite. In systems with myxoma virus and Mycoplasma gallisepticum are described changes of virulence and manipulation with host immune response. Myxomatosis should be known for its increasing virulence because of horizontal transmission. But after many years coevolution between European rabbit (Oryctolagus cuniculus) settled on low value in three different places. Second system represents young evolution between mycoplasma and house finch (Haemorhous mexicanus) which offer opportunity to watch new beggining of defense mechanism against parasite.
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Polymorphism of the transcription factor NF-κB and Toll-like receptor 2 in a production population of cattle (Bos taurus L.)
Samaké, Kalifa ; Novák, Karel (advisor) ; Vinkler, Michal (referee)
The broader purpose of the work is to find and interpret polymorphism in the genes of natural immunity of cattle to be used to improve disease resistance. The NGS method on the PacBio platform was applied for the resequencing of the gene for the key receptor of innate immunity TLR2 and two genes coding for the components of the downstream transcriptional factor NF-κB. In the population of 149 bulls of the Czech Simmental breed, 22 polymorphisms were found in the gene NFKB1 (5 new), while in the NFKB2 gene 13 SNP were found (10 new). 21 SNP were found in the TLR2 gene (3 new). Of the 56 found polymorphisms, 6 SNPs were nonsynonymous. One SNP leads to a change R474G in the NFKB1 product and five to changes E63D, R152Q, I211V, R563H and H665Q in the protein TLR2. Knowledge of the haplotypes facilitated the development of individual genotyping reactions. In TLR2, a high number of haplotypes was detected, both from the PacBio reads and the statistical reconstruction. In addition, two clusters of haplotypes were ditinguished inTLR2, possibly due to diversifying selection or introgression. The knowledge of genetic diversity in the population allows for the planned association studies with health data. Localization in functional domains allow to define the change with the greatest effect, in particular...
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