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Evolution of host specifity in cuckoo bees of the genus Sphecodes (Hymenoptera)
Habermannová, Jana ; Straka, Jakub (advisor) ; Kratochvíl, Lukáš (referee)
Cuckoo bees behave similarly to the well-known birds, cuckoos - they lay eggs in the nests of other bees. Proposed thesis charts the evolution of host specialization within the strictly cuckoo genus Sphecodes. According to the classical view based on the Red Queen hypothesis, parasites should gradually specialize during evolution to keep pace in the "arms race" with their hosts. Specialization is also perceived as an evolutionary dead end - narrow adaptation prevents change of host. To test these hypotheses phylogeny of tribus Sphecodini based on the partial sequences of five genes was constructed. For each ancestor has been by two methods of mapping ancestral characters (Bayesian method, Maximum Parsimony) specified, whether it was specialist or generalist and which kind of host or hosts it had. The results show that the original strategy of genus Sphecodes is specialization and generalists originated from specialized ancestors only recently. The results also show that the jumps between the hosts are common. These findings are inconsistent with the Red Queen hypothesis as well as with the view that specialization is an evolutionary dead end. Falsity of these hypotheses within the genus Sphecodes established also likelihood ratio test, in which the likelihood of model allowing two-way transition...
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Functional analysis of plant Arp2/3 complex subunits
Kukla, Jakub ; Schwarzerová, Kateřina (advisor) ; Honys, David (referee)
1. Abstract ARP2/3 complex is well studied in case of animals, it plays key roles in motility of cells and intracellular organels. It's malfunctions result in severe growth disorders and even lethality of affected cells. On the contrary, plant cells do not exhibit such dramatic phenotype of ARP2/3 complex mutations like it is by animals. It is possible that just the different life strategies of plants and animals contribute to differences in a way how animal and plant cells use their cytoskeleton, where ARP2/3 complex is it's part as well. It is highly conserved 7 protein complex from yeast to human. His main functions are creation of new "de novo" actin filaments, actin branched filaments network. Some of the parasite organisms are capable of missusing its nucleator activity to actively move inside of host cell. Because of the plant cells are sourounded by the cell wall, which give them support in creating various shapes and also hinders active movement of the whole cell body, it is likely that ARP 2/3 complex could be possibly involved in novel plant specific functions as well. If we think about the different life strategy of plants and animals we can not ignore all the things these two kingdoms have in common regarding to cytoskeleton processes. That is the need both for vesicular transport and...
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Nesting biology and alternative reproductive strategies in bees of the genus Anthophora (Hymenoptera)
Macháčková, Lenka ; Straka, Jakub (advisor) ; Tropek, Robert (referee)
My thesis is focused on the nesting behaviour and reproductive strategies of solitary bee Anthophora plumipes, which nests in colonies and builds the nests in the ground. During behavioral observation in seasons 2009 and 2010 the basic demographic characteristics of studied species were described and all the observed behavioral patterns were described in ethogram. Existence of intraspecific cleptoparasitism in form of usurpations was proved. From field usurpations were 22-33 % assessed as a real usurpations and 66-67 % were cases of use of an empty nests. Number of usurpation was constant throughout the season. There was increase in cases of use of empty nests at the end of the season. The underground nests were marked by lanthanides. This way the interactions between females could bee observed. In this way the intraspecific cleptoparasitism could be found out. 25-32 % samples were positive from 152 samples, that were measured on ICP. It suggests relatively low effectivity of marking. The mark losses reach up to 42 % during processing.
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Investment in reproduction and nest defense in waterfowl
Javůrková, Veronika ; Albrecht, Tomáš (advisor) ; Remeš, Vladimír (referee) ; Weidinger, Karel (referee)
Investment in reproduction is considered to be crucial component of life history traits. Reproductive success is however constrained by generally unpredictable environmental conditions. Based on "bet hedging" theory, individuals are forced to eliminate such unpredictability via the mixed strategy to maximize their long-term fitness. Predation represents underlying factor affecting individual reproductive success, and it undoubtedly lies behind the evolution of alternative reproductive strategies such as extra-pair paternity and conspecific brood parasitism. Behavioral mechanisms related to nest defense are thought to be investment in reproduction in accordance with trade-off between actual and residual reproductive value. Despite the extensive interest in the principles associated with parental investment into the nest defense, studies describing in detail the pattern of particular antipredator strategies are rare. Similarly, mechanisms responsible for maintenance of egg- viability during prolonged egg-laying period in species delayed the onset of incubation are poorly understood. In accordance with mentioned themes, this thesis includes publications aimed at aspects of reproductive biology and antipredator behavior in Mallards (Anas platyrhynchos). Particular publications concretely documented: a)...
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Nesting behaviour and alternative reproductive tactics in solitary bees (Hymenoptera: Apoidea)
Rezková, Kateřina ; Straka, Jakub (advisor) ; Konvička, Martin (referee)
Proposed thesis describes nesting behaviour of gregarious solitary bee species Andrena vaga. The knowledge of behaviour in solitary bees can be very important, because solitarity might represent the initial point in the evolution of eusociality and obligate cleptoparasitism. A population of the studied species was observed continuously for two nesting seasons, which enabled me to describe basic demographic characteristics of studied species such as lenght of bee season, longevity, density of population, number of nests per female life, etc. All the observed behavioural patterns were described in ethogram and their exact position in provisioning cycle was determined. This information helped me to compile average daily activity of studied species. I found out major differences in bee behaviour in both years and between nonparasitized and stylopized (parasitized by Stylops) bees. I proved the existence of intraspecific cleptoparasitism in form of usurpations. Because it is crucial to link female to the provisioned cell for the detection of intraspecific cuckoo-like behaviour, I tested two new methods of underground cell marking - protein marking and fluorescent dye marking. Powered by TCPDF (www.tcpdf.org)
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Forms of Regional Co-operation in the Light of the Promotion of Production
BLÁHOVÁ, Jana
At the beginning of the year 2008 I chose the topic for my bachelor diploma paper {\clq}"Forms of Regional Co-operation in the Light of the Promotion of Production". I have chosen the group called LAG Strakonicko which is a Local Action Group located in my home town Strakonice. I have found out that activity of this group is based on the cooperation on the tripartite basis (public administration, non-profit making organizations and businessmen). To gain money from the European Agricultural Fund for Rural Development for projects mentioned in LEADER strategy plan a group should prove its existing activity in accordance with LEADER rules and it should have a carefully prepared LEADER strategy plan. The common vision of all members of LAG Strakonicko including a four village association (the Region of Middle Otava, the Region of Lower Otava, Strakonice Region and Šumava Podlesí) is the vital countryside which will be inspired by its history and tradition of the given regions and which will continue in its development and which will use its current potential at the same time. From my point of view the manager LAG Strakonicko Bc. Jiřina Karasová and her assistant Ing. Věra Dědíková are right people at the right place because they know everything about the region they are working in, they know all legal rules and mainly they work with enthusiasm on promotion and regional development. One part on my research was a questionnaire among businessmen who are not members of MAS. Local farmers were the most informed among the interviewees, other businessmen mostly did not know anything about the activities or they did not know anything about the existence they of this group at all. The interviewees see the biggest negatives in demanding administrative work on application forms, bureaucracy, problems with project application forms and financing in advance. The last part of my research was a questionnaire among businessmen who are members of MAS. I have found out that approximately 33,3% of the members were founders. For 83,3% of interviewees the membership in MAS met their expectations. The results of the survey show that the membership in MAS is advantageous for businessmen at least concerning the LAG Strakonicko. The proves of this fact are successfully approved and financially encouraged projects ``Country market-hall{\crq}q and ``Strategic plan LEADER 2007 {--} 2013{\crq}q. A great variety of prepared projects will be carried out thanks to gained financial support. The above mentioned projects include for example, renovation of a hand carved bee house and its functional regeneration, mile restoration and many other interesting projects influencing a successful regional development.
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Biotransformation and Transport of Xenobiotics in Helminths
Bártíková, Hana ; Szotáková, Barbora (advisor) ; Horák, Petr (referee) ; Machala, Miroslav (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Department of Biochemical Sciences Candidate Mgr. Hana Bártíková Supervisor Doc. Ing. Barbora Szotáková, Ph.D. Title of Doctoral Thesis Biotransformation and transport of xenobiotics in helminths Infectious diseases caused by parasitic helminths are a major problem threatening health of domestic and wild animals and affecting agricultural industry worldwide. Treatment of helminthoses is based on administration of anthelmintic drugs, with benzimidazoles being the most important group. Unfortunately, the irrational use of similar anthelmintics has led to the development of drug resistance in helminths, thus causing a serious problem in the veterinary practice. Possible mechanisms of drug resistance development include changes of pharmacokinetic processes (changes in drug transport or increased drug deactivation), which are based on an increased activity of biotransformation enzymes and transporters in helminths. Understanding the mechanisms of drug resistance and defence strategies of parasites against drugs can prolong the efficacy of current anthelmintics and help to find new strategies for the control of helminthoses. Although drug metabolizing enzymes and transporters of helminths serve as an efficient defence...
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Dual role of CD9 protein in mast cell activation
Machyna, Martin ; Dráber, Petr (advisor) ; Černý, Jan (referee)
Mast cells are well known effector cells in immune system. They have been implicated in such important processes as host defense against bacteria, toxins or parasites. However, in some cases they can develop improper reaction against harmless environmental antigens and thus causing allergies. It is therefore essential to understand signaling events that lead to activation of these cells in order to develop new treatment strategies. Newly prepared rat monoclonal antibody of IgG1 subtype raised against murine mast cells was characterized and found suitable for flow cytometry, immunoblotting and immunoprecipitation. Employing of optimized procedure for immunopurification in combination with mass spectrometry led to identification of its target cluster of differentiation (CD)9 protein. CD9 is a member of large protein family called tetraspanins. Functional studies showed that binding of this antibody to mast cells induced degranulation and early activation events such as increased tyrosine phosphorylation and enhanced levels of free cytoplasmic calcium. Interestingly, subsequent activation of these cells via antigen-mediated aggregation of the high-affinity IgE receptor (FcεRI) led to decreased degranulation, calcium response and tyrosine phosphorylation of several substrates. Importantly, anti-CD9 antibody did...
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Fungi associated with tree roots
Charvátová, Markéta ; Baldrian, Petr (advisor) ; Gryndler, Milan (referee)
In contrast to the bulk soil environment, plant roots represent a habitat with higher nutrient availability due to the supply of photosynthesis-derived C-containing compounds. The roots thus support the life of various microorganisms that use such compounds, but the root-associated microbes in the same time may face a limitation in N and P availability. Unlike bacteria, many filamentous fungi are able to transport these compounds from soil and their mycelia thus typically extend into this environment. Ectomycorrhizal fungi are a typical example of this nutrition strategy. Tree roots produce exudates, that differ in thein composition for each species and they can also differ among individuals. It causes a high diversity of root-associated fungi. Soil is also inhabited by parasitic and saprotrophic fungi. Composition and activity of microbial communisies in the rhizosphere differ from the bulk soil. This work points at the differences of the rhizosphere and builk soil, the importance mycorrhizal fungi and it presents an overview of fungal species that have been found on the roots of spruce - Picea abies. Key words: fungi, mycorrhiza, soil, rhizosphere, Picea abies
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Extra-pair fertilizations and the opportunity for sexual selection in Barn swallows
Michálková, Romana ; Albrecht, Tomáš (advisor) ; Šálek, Miroslav (referee)
Generally it is assumed, that sexual selection drives the evolution of elaborate traits. The strength of sexual selection has traditionally been attributed to varinace in reproductive success among individuals. This variance is mainly caused by the number of mating partners and the number of sired offspring. Both males and females can increase their reproductive success by alternative reproductive strategies - extrapair copulations and intraspecific brood parasitism. In our study we tested the relationship between male ornamentation and success in extra-pair and within-pair paternity and the total male reproductive success in barn swallow (Hirundo rustica), a socially monogamous species with high levels of extrapair paternity. The results suggest more colourful throat to indicate male reproductive success. Dark rusty males were less often cuckolded and they have higher total fertilization success than drab ones. Tail length did not affect neither within- nor extra-pair fertilization success, however, previous studies have concluded that reproductive success of male barn swallows is positively related to the tail ornaments. Our results confirm that extra-pair paternity considerably increase variance in reproductive success among barn swallow males. We show that within-pair success may increase the...
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