Functional characterization of the insulin signaling pathway in the hard tick Ixodes ricinus
KOZELKOVÁ, Tereza
2024 - English In this thesis, the molecular and functional characterization of the insulin receptor signaling pathway (ISP) in hard tick Ixodes ricinus was characterized. As obligatory blood-feeding ectoparasites, ticks play a crucial role in the transmission of various pathogens, including bacteria, viruses, and protozoa, which has a significant impact on human and animal health. The parasite is strictly bonded with its host through a unidirectional transmission of nutrition for its survival, development, and reproduction. The ISP, a highly conserved system, regulates numerous physiological and anabolic processes to nutritional availability. This study aims to investigate the functionality of key components of the ISP pathway identified in the midgut transcriptome, namely the insulin receptor (IrInR), the protein kinase B called AKT (IrAKT), and the target of rapamycin (IrTOR). To achieve this goal, the expression profiles of these components in tick tissues during feeding and after detachment were investigated using qRT-PCR. Additionally, RNAi silencing of individual components was performed, and the phenotype of the ticks was observed. To further clarify the effects of ISP, immunization of rabbits with recombinant IrInR protein and tick infestation were investigated. Available in the Digital Repository of University of South Bohemia. Functional characterization of the insulin signaling pathway in the hard tick Ixodes ricinus

In this thesis, the molecular and functional characterization of the insulin receptor signaling pathway (ISP) in hard tick Ixodes ricinus was characterized. As obligatory blood-feeding ...

KOZELKOVÁ, Tereza
Jihočeská univerzita v Českých Budějovicích, 2024

Oligomerization state and pigment contents of algal light-harvesting proteins
MALINOVÁ, Kateřina
2023 - English Light-harvesting antennas (LHCs) from four microalgae species (diatom Phaeodactylum tricornutum, haptophyte Emiliania huxleyi, and two eustigmatophytes Nannochloropsis oceanica and Trachydiscus minutus) were studied. LHCs were extracted and purified using sucrose gradient ultracentrifugation and ion-exchange chromatography. Oligomerization states of LHCs were assessed using two independent methods - CN-PAGE and size-exclusion chromatography. Effects of the purification on LHC pigment composition was assessed using HPLC. Light-harvesting antennas (LHCs) from four microalgae species (diatom Phaeodactylum tricornutum, haptophyte Emiliania huxleyi, and two eustigmatophytes Nannochloropsis oceanica and Trachydiscus minutus) were studied. LHCs were extracted and purified using sucrose gradient ultracentrifugation and ion-exchange chromatography. Oligomerization states of LHCs were assessed using two independent methods - CN-PAGE and size-exclusion chromatography. Effects of the purification on LHC pigment composition was assessed using HPLC. Keywords: pigments; LHC; HPLC; alga; SEC; IEC Available in the Digital Repository of University of South Bohemia. Oligomerization state and pigment contents of algal light-harvesting proteins

Light-harvesting antennas (LHCs) from four microalgae species (diatom Phaeodactylum tricornutum, haptophyte Emiliania huxleyi, and two eustigmatophytes Nannochloropsis oceanica and Trachydiscus ...

MALINOVÁ, Kateřina
Jihočeská univerzita v Českých Budějovicích, 2023

Evolúcia socio-kultúrnych adaptací člověka: Fylogenetická medzi-kultúrna perspektíva
ŠAFFA, Gabriel
2023 - English This thesis investigates the adaptive significance of seemingly maladaptive human behaviors or cultural norms that are often viewed as responses to intra- and inter-sexual conflict. It combines behavioral ecological approach with phylogenetic comparative methods to study evolutionary origins and maintenance of these practices, using samples of ethnographically documented human societies. The thesis is divided into three sections. The first section is the introduction to evolutionary sciences of human behavior, including an overview of the theoretical perspectives and a critical evaluation of the methodological approaches to macro-evolutionary studies of human behavior and culture. The second section consists of three chapters - two published research papers and a manuscript that is currently under review. The first paper investigates female and male genital mutilation/cutting practices, their evolutionary history, and socio-ecological correlates; the second paper investigates restrictions on female premarital sex and evaluates the three hypotheses explaining them - male, female, and parental control hypothesis; the third paper investigates the causes of socially imposed monogamy and evaluates the competing hypotheses explaining its prevalence in stratified, agricultural societies. The last section summarizes the results of the three studies and concludes with perspectives of future research. Keywords: adaptation; causal inference; cultural evolution; human behavioral ecology; phylogenetics; regression Available in the Digital Repository of University of South Bohemia. Evolúcia socio-kultúrnych adaptací člověka: Fylogenetická medzi-kultúrna perspektíva

This thesis investigates the adaptive significance of seemingly maladaptive human behaviors or cultural norms that are often viewed as responses to intra- and inter-sexual conflict. It combines ...

ŠAFFA, Gabriel
Jihočeská univerzita v Českých Budějovicích, 2023

Environmental and socio-cultural determinants of language skills and ethnobiological knowledge in Papua New Guinea and Cameroon
KIK, Alfred
2023 - English Available in the Digital Repository of University of South Bohemia. Environmental and socio-cultural determinants of language skills and ethnobiological knowledge in Papua New Guinea and Cameroon

KIK, Alfred
Jihočeská univerzita v Českých Budějovicích, 2023

Functional analysis of cryoprotectant system in Chymomyza costata
GRGAC, Robert
2023 - English In this study, employing an integrated approach that involves transcriptomics, metabolomics, and other techniques, we aimed to understand the mechanistic roles of the cryoprotective system underlying extreme freeze tolerance in the larvae of the drosophilid fly, Chymomyza costata. Metabolomics unveiled the complex composition of the seasonally accumulated larval innate mixture of putative cryoprotectants. This mixture was predominantly composed of proline and trehalose, supplemented by minor components (glutamine, asparagine, betaine, sarcosine, glycerophospho-choline, and ethanolamine). We identified food ingestion as a significant source for the direct assimilation of amino compounds, while glycogen and phospholipids served as the primary internal sources for the biosynthesis of other cryoprotectants. The utilization of MALDI-MSI to observe cryoprotectants revealed distinct behaviors of proline and trehalose during ecologically relevant, gradual inoculative extracellular freezing of larvae. Trehalose exhibited accumulation in partially dehydrated hemolymph, inducing a transition to the amorphous glass phase. On the other hand, proline migrated to the boundary between extracellular ice and dehydrated hemolymph and tissues, forming a layer of dense viscoelastic liquid. Finally, through a combination of in vivo and in vitro assays, we found that cell membranes are likely targets of freezing injury, while their integrity is sustained by accumulated small cryoprotective molecules and proteins in cold-acclimated C. costata larvae. Contrary to our expectations, our assays did not provide support for the hypothesis that proteins (soluble enzymes) require in vivo stabilization through the accumulation of cryoprotectants. In this study, employing an integrated approach that involves transcriptomics, metabolomics, and other techniques, we aimed to understand the mechanistic roles of the cryoprotective system underlying extreme freeze tolerance in the larvae of the drosophilid fly, Chymomyza costata. Metabolomics unveiled the complex composition of the seasonally accumulated larval innate mixture of putative cryoprotectants. This mixture was predominantly composed of proline and trehalose, supplemented by minor components (glutamine, asparagine, betaine, sarcosine, glycerophospho-choline, and ethanolamine). We identified food ingestion as a significant source for the direct assimilation of amino compounds, while glycogen and phospholipids served as the primary internal sources for the biosynthesis of other cryoprotectants. The utilization of MALDI-MSI to observe cryoprotectants revealed distinct behaviors of proline and trehalose during ecologically relevant, gradual inoculative extracellular freezing of larvae. Trehalose exhibited accumulation in partially dehydrated hemolymph, inducing a transition to the amorphous glass phase. On the other hand, proline migrated to the boundary between extracellular ice and dehydrated hemolymph and tissues, forming a layer of dense viscoelastic liquid. Finally, through a combination of in vivo and in vitro assays, we found that cell membranes are likely targets of freezing injury, while their integrity is sustained by accumulated small cryoprotective molecules and proteins in cold-acclimated C. costata larvae. Contrary to our expectations, our assays did not provide support for the hypothesis that proteins (soluble enzymes) require in vivo stabilization through the accumulation of cryoprotectants. Available in the Digital Repository of University of South Bohemia. Functional analysis of cryoprotectant system in Chymomyza costata

In this study, employing an integrated approach that involves transcriptomics, metabolomics, and other techniques, we aimed to understand the mechanistic roles of the cryoprotective system underlying ...

GRGAC, Robert
Jihočeská univerzita v Českých Budějovicích, 2023

Structural and functional characterization of the E3 ligase BIRC6
GRATZL, Sascha
2023 - English The aim of the thesis was to characterize the ubiquitin ligase BIRC6 in several contexts. The goal was to expand the knowledge on the selectivity of E1-E2 recognition, to increase the known substrate range of BIRC6, and to elucidate the molecular interactions fulfilled by BIRC6 during autophagy via interaction with GABARAP. In addition, it was aimed to gain a better understanding on the general ubiquitination mechanism in E2/E3 hybrid enzymes, to identify the ubiquitination sites of known apoptotic and autophagic substrates and to enlighten substrate recognition by BIRC6. The aim of the thesis was to characterize the ubiquitin ligase BIRC6 in several contexts. The goal was to expand the knowledge on the selectivity of E1-E2 recognition, to increase the known substrate range of BIRC6, and to elucidate the molecular interactions fulfilled by BIRC6 during autophagy via interaction with GABARAP. In addition, it was aimed to gain a better understanding on the general ubiquitination mechanism in E2/E3 hybrid enzymes, to identify the ubiquitination sites of known apoptotic and autophagic substrates and to enlighten substrate recognition by BIRC6. Keywords: structural biology; cryo-EM; x-ray crystallography; autophagy; apoptosis; inhibitor of apoptosis proteins; AlphaFold2; ATG8; ubiquitin; E3 ligase Available in the Digital Repository of University of South Bohemia. Structural and functional characterization of the E3 ligase BIRC6

The aim of the thesis was to characterize the ubiquitin ligase BIRC6 in several contexts. The goal was to expand the knowledge on the selectivity of E1-E2 recognition, to increase the known substrate ...

GRATZL, Sascha
Jihočeská univerzita v Českých Budějovicích, 2023

Metabolic setup of Drosophila macrophages during the immune response
KREJČOVÁ, Gabriela
2023 - English Adjustment of cellular metabolism is a key function that allows macrophages to fulfill their roles in the body. While the pro-inflammatory polarization of macrophages has been extensively studied in mammalian models, it has not yet been satisfactorily investigated in insects. The study presented in this thesis therefore attempts to elucidate the metabolic setup of macrophages during the immune response in Drosophila melanogaster. Adjustment of cellular metabolism is a key function that allows macrophages to fulfill their roles in the body. While the pro-inflammatory polarization of macrophages has been extensively studied in mammalian models, it has not yet been satisfactorily investigated in insects. The study presented in this thesis therefore attempts to elucidate the metabolic setup of macrophages during the immune response in Drosophila melanogaster. Keywords: makrofág; polarizace; metabolismus; infekce; octomilka; plazmatocyt; imunitní odpověď Available in the Digital Repository of University of South Bohemia. Metabolic setup of Drosophila macrophages during the immune response

Adjustment of cellular metabolism is a key function that allows macrophages to fulfill their roles in the body. While the pro-inflammatory polarization of macrophages has been extensively studied in ...

KREJČOVÁ, Gabriela
Jihočeská univerzita v Českých Budějovicích, 2023

Red-backed shrike (Lanius collurio) versus common cuckoo (Cuculus canorus): An example of ineffective cuckoo-hawk mimicry
KRAUSOVÁ, Ladislava
2023 - English V této práci jsem testovala reakci ťuhýka obecného (Lanius collurio) na hnízdního parazita, kukačku obecnou (Cuculus canorus) (šedá forma), predátora, krahujce obecného (Accipiter nisus) a neškodnou kontrolu, hrdličku divokou (Streptoptelia turtur). Prokázala jsem, že ťuhýci od sebe dokážou rozlišit jednotlivé atrapy a adekvátně na ně reagovat. Navíc jsem prokázala, že imitace krahujce kukačkou je u ťuhýků neúspěšná. In this work, I tested the reaction of the red-backed shrike (Lanius collurio) against a nest parasite, the common cuckoo (Common cuckoo) (grey form), predator, Eurasian sparrowhawk (Accipiter nisus) and harmless intruder, turtle dove (Streptopelia turtur). I proved that shrikes can differ between presented stimuli and adequately respond to them. Moreover, I proved that the cuckoo-hawk mimicry is not successful against shrikes. Keywords: ťuhýk obecný; cuckoo-hawk mimicry; hnízdní parazitismus; obrana hnízda Available in the Digital Repository of University of South Bohemia. Red-backed shrike (Lanius collurio) versus common cuckoo (Cuculus canorus): An example of ineffective cuckoo-hawk mimicry

V této práci jsem testovala reakci ťuhýka obecného (Lanius collurio) na hnízdního parazita, kukačku obecnou (Cuculus canorus) (šedá forma), predátora, krahujce obecného (Accipiter nisus) a neškodnou ...

KRAUSOVÁ, Ladislava
Jihočeská univerzita v Českých Budějovicích, 2023

The role of macrophages in the regulation of systemic metabolism in Drosophila
KREJČOVÁ, Gabriela
2023 - English Macrophages are immensely versatile cells in the mammalian body, fulfilling roles ranging from protection against pathogenic intruders and engulfing apoptotic cells to morphogenesis and maintenance of tissue homeostasis. This impressive functional versatility may be achieved due to plasticity of macrophage cellular metabolism called metabolic polarization. The adoption of different polarization phenotypes by macrophages determines their function and is essential for the health of the organism. Nonetheless, if the cells lose their metabolic plasticity or polarize inadequately to a particular situation, it can lead to the development of chronic pathological states such as metabolic syndrome. Metabolic polarization of immune cells is thus a key factor in determining whether macrophage function within the organism will be adaptive or pathological. Despite Drosophila melanogaster represents a major model organism for immunological studies, the metabolic setup of activated immune cells has not been addressed up to now. The results of this thesis document that Drosophila immune cells undergo metabolic polarization toward aerobic glycolysis when challenged by extracellular bacteria. Mammals alike, this cellular metabolic switch is regulated by the transcription factor HIF1, thus documenting the conservation of this process between insects and vertebrates. Furthermore, we show that the adoption of aerobic glycolysis is directly linked to the production of the signaling factor IMPL2, which induces the mobilization of lipid stores from the fat body via the silencing of insulin signaling. By this mechanism, immune cells secure sufficient nutrients for successful elimination of the pathogen. Moreover, the mammalian ImpL2 homolog IGFBP7 appears to act analogously in the mammalian liver not only during severe infectious states but also in the liver of obese individuals. While such macrophage activity in regulating systemic metabolism is beneficial to the host during bacterial infection, it becomes maladaptive when chronically activated. Further evidence for a metabolism-regulatory role of immune cells has been found during insect metamorphosis and early post-metamorphic development. This thesis documents that during this period, macrophages infiltrate and engulf the histolyzing larval fat body and convert nutrients into storage peptides and lipoproteins. Subsequently, these nutrients are exploited by the maturing adult structures. Macrophages are immensely versatile cells in the mammalian body, fulfilling roles ranging from protection against pathogenic intruders and engulfing apoptotic cells to morphogenesis and maintenance of tissue homeostasis. This impressive functional versatility may be achieved due to plasticity of macrophage cellular metabolism called metabolic polarization. The adoption of different polarization phenotypes by macrophages determines their function and is essential for the health of the organism. Nonetheless, if the cells lose their metabolic plasticity or polarize inadequately to a particular situation, it can lead to the development of chronic pathological states such as metabolic syndrome. Metabolic polarization of immune cells is thus a key factor in determining whether macrophage function within the organism will be adaptive or pathological. Despite Drosophila melanogaster represents a major model organism for immunological studies, the metabolic setup of activated immune cells has not been addressed up to now. The results of this thesis document that Drosophila immune cells undergo metabolic polarization toward aerobic glycolysis when challenged by extracellular bacteria. Mammals alike, this cellular metabolic switch is regulated by the transcription factor HIF1, thus documenting the conservation of this process between insects and vertebrates. Furthermore, we show that the adoption of aerobic glycolysis is directly linked to the production of the signaling factor IMPL2, which induces the mobilization of lipid stores from the fat body via the silencing of insulin signaling. By this mechanism, immune cells secure sufficient nutrients for successful elimination of the pathogen. Moreover, the mammalian ImpL2 homolog IGFBP7 appears to act analogously in the mammalian liver not only during severe infectious states but also in the liver of obese individuals. While such macrophage activity in regulating systemic metabolism is beneficial to the host during bacterial infection, it becomes maladaptive when chronically activated. Further evidence for a metabolism-regulatory role of immune cells has been found during insect metamorphosis and early post-metamorphic development. This thesis documents that during this period, macrophages infiltrate and engulf the histolyzing larval fat body and convert nutrients into storage peptides and lipoproteins. Subsequently, these nutrients are exploited by the maturing adult structures. Keywords: makrofág; metabolismus; imunitní odpověď; polarizace; ImpL2; octomilka; tukové těleso; infiltrace; insulinová rezistence; glukanové částice Available in the Digital Repository of University of South Bohemia. The role of macrophages in the regulation of systemic metabolism in Drosophila

Macrophages are immensely versatile cells in the mammalian body, fulfilling roles ranging from protection against pathogenic intruders and engulfing apoptotic cells to morphogenesis and maintenance of ...

KREJČOVÁ, Gabriela
Jihočeská univerzita v Českých Budějovicích, 2023

Carbohydrates drive growth and longevity tradeoff strategies of plants in the Western United States
SAMRAOUI, Kenz Raouf
2023 - English This study explores the relationship between non-structural carbohydrates (NSCs), growth, and longevity in over 200 vascular plant species across diverse Western U.S. habitats. The research identifies specific roles for NSC compoundsfructans enhance longevity, while simple sugars support rapid growth at the expense of longevity. By elucidating the roles of individual NSC compounds and their relationship with growth and longevity, we are contributing to a deeper understanding of plant adaptation and survival strategies. This study explores the relationship between non-structural carbohydrates (NSCs), growth, and longevity in over 200 vascular plant species across diverse Western U.S. habitats. The research identifies specific roles for NSC compoundsfructans enhance longevity, while simple sugars support rapid growth at the expense of longevity. By elucidating the roles of individual NSC compounds and their relationship with growth and longevity, we are contributing to a deeper understanding of plant adaptation and survival strategies. Keywords: Carbon allocation strategies; Environmental adaptation; Non-structural carbohydrates (NSCs); Plant growth dynamics; United States of America. Available in the Digital Repository of University of South Bohemia. Carbohydrates drive growth and longevity tradeoff strategies of plants in the Western United States

This study explores the relationship between non-structural carbohydrates (NSCs), growth, and longevity in over 200 vascular plant species across diverse Western U.S. habitats. The research identifies ...

SAMRAOUI, Kenz Raouf
Jihočeská univerzita v Českých Budějovicích, 2023