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Retroviral infection of chicken testicular cells in a process of construction of transgenic poultry
Kalina, Jiří ; Škvor, Jiří (advisor) ; Petr, Jaroslav (referee) ; Jílek, František (referee)
Biotechnological research in chicken transgenesis is still lagging beyond the mammals mainly due to the specificities of avian reproductive system. This thesis is trying to offer functionally complex approach to the chciken transgenesis through one of the techniques. Common transfection techniques were applied on chicken blastodermal and testicular cells to affirm this approach. Our original techniqe of sterilization of chicken testes was improved and applied. Stained testicular cells of donor male were transplanted into sterilized acceptors testes and subseqent tubuli recolonization and sperm production were described. The retroviral- based vector was developed and transplanted testicular cells were successfuly infected. Carried marker transgene (Green fluorescence protein, GFP) was detected in DNA of produced sperms and no significant CpG methylation was detected when sreening infected cells. Through the flow cytometry, testicular cells used for transplantation were analyzed. All major spermatogonia-derived populations were described including the side population (SP), possible group of spermatogonial stem cells.
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Cell signaling pathways controlling meiotic maturation of mammalian oocytes
Šolc, Petr ; Motlík, Jan (advisor) ; Petr, Jaroslav (referee) ; Dráber, Pavel (referee)
4 2 Summary in English The female germ cells called oocytes arise from the primordial germ cells during embryogenesis. They are essential for the reproduction. Already during embryogenesis oocytes enter meiosis, however, they arrest at the dictyate stage of prophase I. After onset of sexual maturity luteinizing hormone induces the resumption of meiosis of follicle enclosed oocytes (GV stage) in animals (in vivo) but removing of oocytes from follicles and culture in a suitable medium allows the spontaneous resumption of meiosis in vitro. Nuclear envelope break down (NEBD or GVBD) is the first visible mark of the meiosis resumption. Later after GVBD, the metaphase I (MI) spindle forms and after all chromosome bivalents are correctly attached to microtubules (MTs) anaphase I occurs. Following meiosis I completion, oocytes enter directly meiosis II and arrest at metaphase II (MII). These oocytes are fertilizable and sperm trigger meiosis II completion. The development from GV to MII oocytes is governed mainly by meiosis promoting factor (MPF) that consists of cyclin dependent kinase 1 (CDK1) and cyclin B (CCNB). On the mouse oocytes, we have shown using functional studies (RNA interference, mRNA microinjection) that phosphatases CDC25A and B cooperate in the induction of CDK1 activity and resumption of meiosis....
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Chemical signals and reproductive processes of the house mouse (Mus musculus)
Černá, Martina ; Stopka, Pavel (advisor) ; Petr, Jaroslav (referee) ; Sedláček, Radislav (referee)
The aim of my thesis was to identify proteins involved in chemical communication and especially those that are involved in sexual signalling. Volatile chemical signals are transported with lipocalins in their beta-barrel structure to present their ligands to receptors or out of the body. Thus, I focused on the identification of these proteins in saliva and vaginal secretion of the house mouse using proteomic and transcriptomic approaches. Due to a cyclic manner of reproduction and its hormonal control, I have also focused on the role of estradiol on sperm phenotype in the laboratory mouse. We have identified an elevated sexual dimorphism in several lipocalins (i.e. 10 out of 20) in the saliva proteome where they may play a role in sexual signalling (i.e. similar to their described roles in the mouse urine). Interestingly, vaginal secretion also contains lipocalins and they rise from proestrus to estrus and remain steady during metestrus. Such variation provides evidence that they serve sexual signalling, however, due to their elevated levels during metestrus it is most likely that their ligands function as signals and not the proteins themselves. On the level of sperm phenotype, we have provided evidence, that experimental concentrations of estradiol have differential effects on sperm. This is due...
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The impact of intracytoplasmic sperm injection on succesful development and fertility in selected mammal species
Kaufman, Jonáš ; Petelák, Aleš (advisor) ; Petr, Jaroslav (referee)
5 Abstract This thesis aims to summarize the current knowledge about the development and reproductive capacities of individuals conceived by artificial conception, especially intracytoplasmic sperm injection (ICSI), and to make a comparison with naturally conceived ones. The focus is primarily on human assisted reproduction, even though scientific work with human gametes and embryos faces ethical difficulties. However, the main objective is to determine whether ICSI has a negative effect on offspring, partially using results from animal models. Furthermore, this thesis compares birth outcomes, incidence of birth defects, cognitive and reproductive abilities and both genetic and epigenetic integrity of individuals conceived naturally with those conceived via ICSI. As of yet, according to available information, ICSI appears to be a safe artificial method of reproduction. Poor results may often either be explained by the reduced fertility of parents, or their significance is negligible. Keywords: artificial fertilization, ART, ICSI, reproduction, offspring, mouse, livestock, human
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Maternal-fetal cellular trafficking: clinical implications and consequences
Knížková, Karolina ; Černý, Jan (advisor) ; Petr, Jaroslav (referee)
Microchimerism is the presence of small population of cells with a different genetic information within the organism, which can result from bidirectional transfer of the cells between the mother and fetus during pregnancy. It is very studied phenomenon whose biological role is not clear yet. The presence of fetal cells in mother's body is associated with both positive and negative effects on maternal health. Microchimerism plays a role in cancer or autoimmune disease and it is implicated in development of tolerance mechanisms during pregnancy. Microchimerism could be used in prenatal diagnostics for aneuploidies or in prediction of complications during pregnancy.
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Signaling pathways and genes regulating oocyte maturation in pig
Blaha, Milan ; Procházka, Radek (advisor) ; Krylov, Vladimír (referee) ; Petr, Jaroslav (referee)
The gonadotropin-induced resumption of meiosis and cumulus expansion in preovulatory follicles is preceded by expression of epidermal growth factor (EGF)-like factors, amphiregulin (AREG) and epiregulin (EREG), in mural granulosa and cumulus cells. In vitro, the EGF-like peptides are also produced in cumulus cells upon stimulation by FSH. Both FSH and the EGF-like peptides stimulate resumption of meiosis and cumulus expansion in vitro via activation of a broad signaling network in cumulus cells. To define signaling pathways that drive FSH- and AREG-induced cumulus expansion and meiotic resumption, in vitro cultured pig cumulus-oocyte complexes (COCs) were treated with specific protein kinase inhibitors. The results document that FSH-stimulated, but not the AREG-stimulated resumption of meiosis, depends on the PKA and MAPK14 activities; both modes of stimulation require activation of EGFR and MAPK3/1. To characterize the effects of FSH and EGF-like peptides on gene expression in cumulus cells, transcriptomes of cumulus cells were analysed using microarray approach. Both FSH and AREG+EREG increased the expression of genes associated with regulation of cell proliferation, blood coagulation and extracellular matrix remodeling. In contrast to AREG+EREG, FSH also increased the expression of genes coding...
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Expressing Causation in the Czech and Spanish Language
Petr, Jaroslav ; Čermák, Petr (advisor) ; Zavadil, Bohumil (referee)
Expressing Causation in Czech and Spanish Language The subject of this thesis, as is evident from the title, consists in expression of causation in Spanish and its equivalents in the Czech language. We dealt with the issue of the causation in both formal and practical perspective. As a basic material, we have used not only Spanish, but also Czech philological publications. We based particularly on the article written by Petr Čermák and Pavel Štichauer called Španělské a italské faktitivní konstrukce hacer/fare + sloveso a jejich české ekvivalenty, as well as from selected chapters of Gramática descriptiva de la lengua española written by different authors. The work is divided into a theoretical part (Chapters 1-4) and a practical part (5-6). In introduction, we set ourselves the goals, we have outlined the research methodology using a parallel corpus InterCorp, which we described in detail. At the theoretical level, we discussed the question of the translation direction and its effect on our research. Furthermore, we defined the terms of causation, causative verb and factitiveness, factitive verb, to be able to continue working with it. We have commented the form of the causative verbs in Czech and their most distinctive features, including a test for distinguishing causative verbs from non-causative verbs....
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Hormonal Aspects of Antler Growth Regulation
Kužmová, Erika ; Bartoš, Luděk (advisor) ; Petr, Jaroslav (referee) ; Kierdorf, Uwe (referee)
Hormonal aspects of antler growth regulation Erika Kužmová Abstract Deer antlers are the only mammalian organ that completely regenerates and therefore they became an object of rising interest as a potential model for bone growth and development. In recent years, it has been confirmed that annual regeneration of the antler is initiated from the stem cell niche localised in the pedicle periosteum. Antlers grow to the length at the tip. Only a little is known about endocrine stimulation of antler growth and some discrepancy has arisen between in vivo and in vitro studies over the decades. As the secondary sexual character, the antler cycle timing and growth are linked to seasonal levels of testosterone. Since the levels are at their minimum during the antler growth phase, according to many mainly in vitro studies, insulin-like growth factor-1 (IGF-1) tends to be accepted as the "antler stimulating hormone". Since the conclusion about the role of IGF-1 was contradictory to previous opinions and also in contrast with our own experience, we aimed to verify the role of IGF-1 in vitro. Our ex- periments were based on existing in vivo studies demonstrating the importance of testosterone, even in its low levels, and on the hypothesis that testosterone should be the "antler stimulating hormone". We performed in vitro...
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Transcriptomics of bovine preimplantation embryo genome activation in vivo and in in vitro culture conditions
Vodičková Kepková, Kateřina ; Kaňka, Jiří (advisor) ; Petr, Jaroslav (referee) ; Krylov, Vladimír (referee)
The goal of the thesis was to characterize transcriptional profiles of in vivo and in vitro derived embryos during bovine minor and major embryonic genome activation and to identify mRNA transcripts newly synthesized during these stages. In our first work we have concentrated on the study of minor genome activation at the 4-cell stage of embryo. Using SSH, we have identified 31 amplicons homologous with already identified genes. We have selected 5 of these for detailed study of their expression during the whole period of preimplantation development: centromere protein, 350/400 kDa (CENPF, mitosin), splicing factor arginine/serine-rich 3 (SRFS3), high mobility group nucleosomal binding domain 2 (HMGN2) protein and eukaryotic translation initiation factors EIF4A2 a EIF4E. All these genes play an important role in the early embryo development. SRFS3 is the first described gene with an important function in preimplantation development, which is expressed already during bovine minor genome activation, and its transcription is α-amanitin sensitive during this period. We have selected CENPF gene for a more thorough study. By silencing its expression by the injection of CENPF dsRNA into the zygote, we have studied its function throughout the whole preimplantation development of bovine embryo....
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Effect of hydrogen sulphide on aging of porcine oocytes in vitro
Krejčová, Tereza ; Petr, Jaroslav (advisor) ; Ješeta, Michal (referee)
Unfertilized or parthenogenetically non-activated porcine oocytes matured in vitro conditions are subjected to a process known as aging. During such development, porcine oocytes undergo the complex of the structural and functional changes, which can result in spontaneous parthenogenetic activation, fragmentation or lysis. After three days of culture in our condition, 23% of oocytes remained at the stage of metaphase II, 48% of oocytes were spontaneously parthenogenetically activated, 26% of oocytes were subjected to fragmentation and 3% of oocytes were lysed. The complete suppression of porcine oocyte fragmentation during the process of aging occurred during oocytes cultured in medium with sulphide donor Na2S in concentrations 150 µM and 300 µM. Inhibition of enzymes catalyzing the synthesis of hydrogen sulfide in the oocytes during the process of aging (cystathionine-gamma-lyase and cystathionine beta-synthase), iniciates earlier onset of oocytes fragmentation. The effect of both inhibitors could be completely reversed by using sulphide donor Na2S. The process of aging in porcine oocytes significantly reduces the success of the activation processes. Parthenogenetic activation occurred in 94% of pig oocytes, which were not subjected to aging. The proportion of activated oocytes after exposure to 24...
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