|
|
Development and function of endocrine cells of the pancreas
Hamplová, Adéla ; Pavlínková, Gabriela (advisor) ; Berková, Zuzana (referee)
Diabetes mellitus affects nearly 300 million people in the world. The development of diabetes is caused by dysfunction or by reduction of insulin-producing β-cells that are part of the endocrine pancreas. Therefore, the most critical step for understanding the pathophysiology of diabetes and for restoring lost β cells is the identification of molecular cues that specify the cellular phenotype in the pancreas. This work is based on the hypothesis that the transcription factor NEUROD1 is a key factor for the development of the pancreas and for the maintenance of endocrine tissue function. Neurod1 conditional KO mutants (Neurod1CKO) were generated using the Cre-loxP system by crossing floxed Neurod1 mice with Isl1-Cre line. Immunohistochemical analyses of the pancreas at embryonic day 17.5 and postnatal day 0 showed that the deletion of Neurod1 negatively affected the development, organization of endocrine tissue, and total mass of pancreatic endocrine cells. To better understand molecular changes, quantitative PCR was used to analyse mRNA expression in the developing pancreas at the age of embryonic day 14.5 and postnatal day 1. Genes important for the development and function of the pancreas have been selected for the study of expression changes. These analyses showed changes in expression of genes...
|
|
|
Deciphering the biological role of Ddi1-like protein family
Sivá, Monika ; Grantz Šašková, Klára (advisor) ; Bařinka, Cyril (referee) ; Stopka, Pavel (referee)
Ddi1-like protein family has been recently raised into the spotlight by the scientific community due to its important roles in cellular homeostasis maintenance. It represents a specific group among shuttling proteins of the ubiquitin-proteasome system. When compared to other shuttles, Ddi1-like protein family members harbor a unique retroviral-protease like domain besides the conventional ubiquitin-like (UBL) domain and domains interacting with ubiquitin. In addition, a helical domain of Ddi (HDD) has been recently found in most of the orthologs. In this thesis, I focus on characterization of several members of Ddi1-like protein family, both on molecular level using NMR and in model mouse strains via a variety of biological methods. Solution structure of the UBL domain of Ddi1p of S. cerevisiae was solved and its characteristics were compared to those of the UBL domain of its human ortholog. Furthermore, we show that human DDI2 specifically binds to ubiquitin with its terminal domains, both the UBL and the UIM; however, with very low affinity in contrast to binding properties of its yeast counterpart. Our study also show that hDDI2 does not form a head-to-tail homodimer. Based on our structural studies, we hypothesize that human DDI2 might have evolved a different function compared to its yeast...
|
|
|
Genotype influence on development of infections caused by Trypanosomatidae in mouse
Šíma, Matyáš
Parasitic protists of genera Trypanosoma and Leishmania are members of Trypanosomatidae family. In our studies, we investigated genetic influence on infections caused by these parasites in a mouse model. These diseases are on genetic level controlled by quantitative trait loci (QTLs), when the resulting phenotype is controlled by set of genes with small individual effect. As a mouse model for mapping of QTLs controlling these infections, we used recombinant congenic strains (RCS). Each RCS carry unique set of 12.5% of the genome from donor parental strain on genetic background of other parental strain. For mapping of QTLs controlling infections caused by Trypanosoma brucei brucei (T. b. brucei) and Leishmania tropica (L. tropica) and eosinophil infiltration into inguinal lymph nodes after Leishmania major (L. major) infection, we used RCS from CcS/Dem series, where STS is donor strain and BALB/cHeA is strain of genetic background. First, it was necessary to find suitable model strains for mapping. In all three studies, we selected RCS, which exceeded range of monitored phenotype parameters in comparison with any other tested RCS or parental strains. Mice of RCS CcS-11 showed shorter survival after T. b. brucei infection and strain CcS-9 exhibited higher eosinophil infiltration after L. major infection. For...
|
|
|
Transcriptional regulation in the development of neurosensory cells in the inner ear
Vochyánová, Simona ; Pavlínková, Gabriela (advisor) ; Schierová, Michaela (referee)
To understand the pathophysiology of hearing loss, it is necessary to identify genes responsible for specification and differentiation of sensory cells and neurons from a common neurosensory progenitor. These factors include LIM-homeodomain transcription factor ISLET1, high-mobility group protein SOX2, and basic helix-loop-helix transcription factors ATOH1, NEUROG1 and NEUROD1. This study aims to map important factors in inner ear development and their interactions with specific focus on transcription factor NEUROD1 and its role in mouse neurosensory inner ear development and function. Key words: inner ear, transcriptional regulation, mouse model, targeted deletion, embryonal development, Neurod1
|
|
|
Genotype influence on development of infections caused by Trypanosomatidae in mouse
Šíma, Matyáš ; Lipoldová, Marie (advisor) ; Krulová, Magdaléna (referee) ; Kolářová, Iva (referee)
Parasitic protists of genera Trypanosoma and Leishmania are members of Trypanosomatidae family. In our studies, we investigated genetic influence on infections caused by these parasites in a mouse model. These diseases are on genetic level controlled by quantitative trait loci (QTLs), when the resulting phenotype is controlled by set of genes with small individual effect. As a mouse model for mapping of QTLs controlling these infections, we used recombinant congenic strains (RCS). Each RCS carry unique set of 12.5% of the genome from donor parental strain on genetic background of other parental strain. For mapping of QTLs controlling infections caused by Trypanosoma brucei brucei (T. b. brucei) and Leishmania tropica (L. tropica) and eosinophil infiltration into inguinal lymph nodes after Leishmania major (L. major) infection, we used RCS from CcS/Dem series, where STS is donor strain and BALB/cHeA is strain of genetic background. First, it was necessary to find suitable model strains for mapping. In all three studies, we selected RCS, which exceeded range of monitored phenotype parameters in comparison with any other tested RCS or parental strains. Mice of RCS CcS-11 showed shorter survival after T. b. brucei infection and strain CcS-9 exhibited higher eosinophil infiltration after L. major infection. For...
|
|
|
Development and function of beta-cells
Hamplová, Adéla ; Pavlínková, Gabriela (advisor) ; Tlapáková, Tereza (referee)
Insulin producing β-cells are located in the endocrine pancreas. They are a part of pancreatic islets of Langerhans along with α-, β-, δ-, ε- a PP-cells producing glucagon, somatostatin, ghrelin and pancreatic polypeptide. Insulin regulates glucose uptake into cells and thus contributes to the regulation of energy metabolism. The development of β-cells as well as the development of the pancreas is a complex process. Developmental processes of proliferation, differentiation and total pancreatic organogenesis are best described in the mouse model. The developmental processes and pancreatic functions are regulated by a network of transcription factors. Pancreatic duodenal homeobox gene 1 is a transcription factor that is expressed in the precursors of endocrine, exocrine and ductal cells. Neurogenin 3 is expressed in precursors of the islets of Langerhans cells. Islet 1 regulates the formation of the islets of Langerhans as well as the pair domains of transcription factors 4 and 6, whose expression is later limited only to β-cells. Transcription factors Islet 1 and Neurod 1 regulate insulin production in β-cells. Mutations in transcription factors lead to the abnormal development and altered function of pancreatic cells, including β-cells. Diabetes mellitus is a disease resulting from defects in...
|
|
|
Generation of the Mouse Model to Delineate Function of Chromatin Remodeling Gene Smarca5 (Snf2h)
Turková, Tereza ; Stopka, Tomáš (advisor) ; Dobeš, Jan (referee)
The chromatin structure, consisting of DNA and histones, changes dynamically during the cell cycle and cell differentiation. DNA can only be transcribed and replicated when it is packaged loosely, whereas tight packaging allows for more efficient storage. Chromatin remodelling is therefore one of the tools of gene expression control. The chromatin remodelling factors recognise chromatin with varying specificity and have an effect on the interaction between DNA and the histones. One of these factors is the Smarca5 protein. This study investigates the role of Smarca5; its goal is to create a mouse model with the ability to trigger Smarca5 overproduction in specific tissues. This model will be used to study the effect of a high, unregulated dose of Smarca5 on the physiological function of the protein. Previous studies have shown that non-physiological expression of a chromatin-remodelling factor can lead to malignant transformation. Our model can help to understand this process. Another goal of this study is to investigate some phenotype aspects of the mouse model with conditional deletion of Smarca5 in T and B cells, in particular the effects of this deletion on progenitor cell differentiation. Our results show that Smarca5 has an important role in lymphocyte development, and we have observed that...
|
|
|
Generation and analysis of double deficient transgenic mice for kallikrein-related peptidase 5 and kallikrein-related peptidase 14
Hanečková, Radmila ; Sedláček, Radislav (advisor) ; Fulková, Helena (referee)
Kallikrein-related peptidases (KLKs) constitute a highly conserved serine protease family. Based on in vitro experiments, KLKs are predicted to play an important role in a number of physiolog- ical and pathophysiological processes. However, their role in vivo remains not fully understood, partially due to a lack of suitable animal models. In this work, we aim to prepare a KLK5 and KLK14 double-deficient mouse model. Both KLK5 and KLK14 were proposed to be involved in epidermal proteolytic networks critical for maintaining skin homeostasis. However, both KLK5 and KLK14 single-deficient mouse models show minimal or no phenotype, likely due to similar substrate specificity resulting in functional compensation. Double-deficient mice cannot be easily obtained by crossing due to localization of the Klk5 and Klk14 genes within the same locus on chromosome 7. We report that KLK5 and KLK14 double-deficient mice were success- fully generated, mediated by transcription activator-like effector nucleases (TALENs) targeting Klk14 by microinjection of TALEN mRNA into KLK5-deficient zygotes. Furthermore, we show that KLK5 and KLK14 double-deficient mice are viable and fertile. We believe that these novel mouse models may serve as a useful experimental tool to study KLK5 and KLK14 in vivo.
|
|
|
Food allergy to wheat flour proteins
Šotkovský, Petr ; Tučková, Ludmila (advisor) ; Panzner, Petr (referee) ; Prokešová, Ludmila (referee)
THESIS SUMMARY Food allergy is one of the frequent disorders and its incidence in paediatric as well as adult population is continuously rising, having doubled in the last two decades. Although wheat belongs to major food allergens and is a staple food in most diets, we have only little knowledge of wheat proteins causing IgE mediated hypersensitivity reaction. Diagnostic approaches of food allergy to wheat have a high sensitivity, but low specificity. Poor predictability and specificity may be associated with the insufficient purity of wheat extracts used in sIgE assays or with the lack of major allergens in these extracts. In the first step, we characterized 19 potential allergens recognised by IgE Abs of allergic patients, using proteomic techniques (1-DE, 2-DE, MALDI-TOF, QTOF and LCQDECA nLC-MS/MS ion trap technique). We identified these IgE-binding molecules such as: α-amylase inhibitors, β-amylase, profilin, serpin, β-D-glucan exohydrolase and 27K protein. To quantify sIgE in patient's sera we developed ELISA using the whole wheat extract and two commercially available α-amylase inhibitors. Second, we developed a procedure that allows isolation of wheat allergens from natural sources using Rotofor cell and HPLC. Twenty-seven potential wheat allergens have been successfully identified; of these, the...
|
|
|
Pre-clinical model of acute promyelocytic leukemia:/study of the anti-leukemic effect induced by ATRA and DNA vaccination
Pokorná, Kateřina ; Holáň, Vladimír (advisor) ; Stöckbauer, Petr (referee) ; Degos, Laurent (referee)
DOCTORAL THESIS 2012 POKORNA Abstract We have used a well characterized transplantable transgenic mouse model which mimics human acute promyelocytic leukemia (APL), both in its biological characteristics and its response to conventional therapeutic drugs. The aim of our study was to better characterize the efficacy of the combined treatment and to determine molecular markers of clinical outcome. We established a minimal residual disease monitoring based on the high sensitivity of detection of PML-RAR transcripts by polymerase chain reaction (PCR) technology in APL mice. We showed that oncogene-specific PCR-based assays allow, like in patients, the diagnosis, follow-up and prediction of disease evolution. Furthermore, PCR assay was used to assess various tissues and organs for the presence of PML-RAR-positive cells in minimal residual disease free long-term survivors. As expected, majority of mice had no measurable tissue level of PML-RAR demonstrating the efficacy of immunotherapy. However, tracking the oncogene-positive cells reveals for the first time that extramedullary PML-RAR-positive cell reservoirs such as the brain may persist and be involved in the leukemia relapse. We aimed at investigating the immune responses involved in the anti-leukemic effect of the combined immutherapy. To evaluate the...
|
guest ::
