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Evolution of karyotypes and sex determination in the turtle family Geoemydidae
Clemente, Lorenzo ; Rovatsos, Michail (advisor) ; Montiel Jimenez, Eugenia Elisabet (referee) ; Castiglia, Riccardo (referee)
(IN ENGLISH) The majority of studied turtles show temperature-dependent sex determination, but genotypic sex determination (i.e. presence of sex chromosomes) was identified sporadically. This thesis aims to investigate and expand our knowledge on the evolution of the karyotype and the sex determination in turtles, particularly focusing on the family Geoemydidae, a group of turtles with previously documented variability in sex determination systems. The presence of sex chromosomes was explored by a combination of conventional and molecular cytogenetic techniques for the analysis of karyotypes, distribution of constitutive heterochromatin (C-banding) and repetitive elements and comparative genome hybridization (FISH, CGH). In total, 49 species of turtles from nine different families were cytogenetically examined in this study. In the family Geoemydidae, a remarkable similarity in karyotypes was identified, consisting of 2n=52 chromosomes (which is suggested to be the ancestral diploid number for all turtles) and a similar topology of rDNA loci and telomeric repeats. Sharma et al. (1975) previously reported ZZ/ZW sex chromosomes in Pangshura smithii. However, in the analysis presented in this thesis, it is suggested a possible misidentification of these sex chromosomes due to erroneous pairing of...
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Study of changes on spindle and chromosomes vitrified and in vitro maturated human oocytes
Holubová, Kateřina ; Kratochvílová, Irena (advisor) ; Libusová, Lenka (referee)
The aim of this work is the comparison of cryoprotection methods for human oocytes regarding their survival rate and subsequent success in in vitro fertilization. This work showed the effect of oocyte maturation characterized by the state of the meiotic spindle, chromosomes and polar body on the success of in vitro fertilization of standard (fresh) and vitrified oocytes. The acquired knowledge will lead to a better understanding of the relationships between the state of oocytes and specific in vitro fertilization and cryoprotection procedures. The final, application-interesting goal will be to propose the optimization of methods for working with oocytes so that the probability of their success in the IVF cycle is as high as possible.
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Genome size evolution in tropical tribe Globba (Zingiberaceae)
Pospíšilová, Monika ; Fér, Tomáš (advisor) ; Zedek, František (referee)
The variability of the genome size reaches several grades even within relatively close groups of plants. The study of the genome size in the phylogenetic context provides interesting results which characterize the evolution of the individual groups of plants. In this respect, tropical plants have yet not been studied. Tropical genus Globba (ca. 100 species) belongs to an economically significant family Zingiberaceae. The diversity centre is found in Thailand but it spreads from east India and southern China up to Indonesia and the Philippines. It is a polyploid complex which exists in two cytotypes within one genus (2n = 32 a 2n = 48); it is characteristic minimally in three out of seven distinguished sections. The aim of this thesis has been a reconstruction of the group phylogeny, discovering the role of the polyploid and evaluation of the genome size evolution of the Globba genus in the phylogenetic context. To this end, modern biosystematic methods were used (flow cytometry, chromosome counting, sequencing of the nuclear and chloroplast DNA regions). Many types of software and statistical methods were used to process and interpret the data. In this group, the genome size was measured for the first time. Out of 87 individuals, the smallest size was measured with Globba nuda (2C = 1.11 pg). The...
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Use of cytogenetical methods in taxonomy of Arachnida (Arachnida)
Alaverdyan, Argam ; Šťáhlavský, František (advisor) ; Johnson Pokorná, Martina (referee)
This bachelor thesis deals with the use of cytogenetic methods in taxonomy of Arachnida. To understand this matter, we need to analyse available information about inter and intraspecific karyotype variability of individual orders. At the beginning of the thesis there is a description of cytogenetic methods used with Arachnida.They are used to gather the karyotype's fundamental information, such as the diploid number of chromosomes, chromosome morfology and possible occurence of sex chromosomes. Main part of the thesis is focused on describing karyotypes of selected orders (Amblypygi, Palpigradi, Pseudoscorpiones, Scorpions, Opiliones and Araneae) and considering the convenience of use of cytogenetic methods for their taxonomy based on these information. The thesis includes current number of described genera (species) of the orders, as well as a number of cytogenetically analyzed genera (species) for comparison.
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Sex Determination in Long-eared Owl (Asio otus) by means of PCR DNA amplification
Pecharová, Šárka ; Řezníček, Jan (advisor) ; Hačecká, Kristýna (referee)
This thesis is focused on determining the sex of the Long-eared Owl (Asio otus). Bird feathers were used during determination that were taken from owl`s back while capturing and ringing. We have attempted to differentiate the sex of captured Long-eared Owl by DNA isolation from blood platelets in the bird quail and subsequent PCR reaction. This thesis also describes the PCR method, which is one of the most used methods in the todays laboratories of many different field of science. I also mention the individual components that are needed for the process of this reaction, its history and its individual steps. Part of my diploma thesis is also the characteristic of the tested order and possible gender division based on morphological features. On this basis, there is also mention of the sexual dimorphism of birds, their plumage and its subsequent coloring. At birds and also at other animals are used different techniques of molecular determination of sex, which I also refer to in my work. Keywords Long-eared Owl (Asio otus), sex, chromosomes, feathers, colour, PCR, DNA
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Study of changes on spindle and chromosomes vitrified and in vitro maturated human oocytes
Holubová, Kateřina ; Kratochvílová, Irena (advisor) ; Libusová, Lenka (referee)
The aim of this work is the comparison of cryoprotection methods for human oocytes regarding their survival rate and subsequent success in in vitro fertilization. This work showed the effect of oocyte maturation characterized by the state of the meiotic spindle, chromosomes and polar body on the success of in vitro fertilization of standard (fresh) and vitrified oocytes. The acquired knowledge will lead to a better understanding of the relationships between the state of oocytes and specific in vitro fertilization and cryoprotection procedures. The final, application-interesting goal will be to propose the optimization of methods for working with oocytes so that the probability of their success in the IVF cycle is as high as possible.
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Karyotype variability of Myriapoda
Kášová, Adéla ; Šťáhlavský, František (advisor) ; Dolejš, Petr (referee)
The bachelor thesis deals with diploid numbers of chromosomes, their morphology and chromosome mechanism of sex determination in four classes of the subphylum Myriapoda. Attention is also paid to mutual phylogenetic relationships within the subphylum. A review of the literature shows the degree of examination of cytogenetic characteristics in individual classes, which is still very low, especially in the classes Pauropoda and Symphyla, and within the class Diplopoda there are still a large number of orders where we completely lack this information. Cytogenetic analyzes revealed a total range of chromosome numbers for: Pauropoda 2n = 12 - 27, Symphyla 2n = 11 - 18, Chilopoda 2n = 14 - 54 and Diplopoda 2n = 8 - 30. Within all four classes, there are both morphologically undifferentiated sex chromosomes and XX/XY and XX/X0 systems. In addition, the X1X1X2X2/X1X20 system is mentioned for the order Spirostreptida. Only a small number of species from the orders Glomerida, Calipodida, Julida, Spirostreptida, Lithobiomorpha and from family Scutigerellidae were able to identify the occurrence of NORs. The work also managed to identify some discrepancies between the data of different works, which shows that especially some older studies were based on poor observation of chromosomes in the karyotype. Key...
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Heterochromatin variants of the human karyotype
Michalová, Michaela ; Šípek, Antonín (advisor) ; Forman, Martin (referee)
Chromosomes are cell structures consist of chromatin, out of which one kind is a constitutive heterochromatin, which contains non-coding sequences only and is transcriptionally inactive. Heterochromatin blocks consist of highly repetitive sequences of satellite DNAs, which allows the parts to be variable. The largest areas of heterochromatin can be found at long arms of chromosomes 1, 9, 16 and Y, but heterochromatin areas also affect the variability of the short arms of acrocentric chromosomes 13 - 15, 21 and 22. This bachelor thesis based on a number of scientific essays summarizes findings about heterochromatic variants, their occurrence, frequency, possibilities of examining as well as their clinical significance in today's world. It mainly highlights their possible connection with reproductive failures and contradictory results of individual observations. Contemporary results show the importance of new laboratory methods (molecularly cytogenetic), which can be used in specifying and more detailed sorting of findings, which were previously tagged as harmless variants according to less accurate banding methods. The summarization implies that emphasis should be put on the study of clinical meaning of heterochromatic variations. These can influence the progress of meiosis and thus trigger...
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Sex Determination in Long-eared Owl (Asio otus) by means of PCR DNA amplification
Pecharová, Šárka ; Řezníček, Jan (advisor) ; Hačecká, Kristýna (referee)
This thesis is focused on determining the sex of the Long-eared Owl (Asio otus). Bird feathers were used during determination that were taken from owl`s back while capturing and ringing. We have attempted to differentiate the sex of captured Long-eared Owl by DNA isolation from blood platelets in the bird quail and subsequent PCR reaction. This thesis also describes the PCR method, which is one of the most used methods in the todays laboratories of many different field of science. I also mention the individual components that are needed for the process of this reaction, its history and its individual steps. Part of my diploma thesis is also the characteristic of the tested order and possible gender division based on morphological features. On this basis, there is also mention of the sexual dimorphism of birds, their plumage and its subsequent coloring. At birds and also at other animals are used different techniques of molecular determination of sex, which I also refer to in my work. Keywords Long-eared Owl (Asio otus), sex, chromosomes, feathers, colour, PCR, DNA
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