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Detection of positive selection in reproductive genes of songbirds
Cakl, Lukáš ; Reifová, Radka (advisor) ; Těšický, Martin (referee)
Reproductive genes are assumed to play an important role in adaptive evolution and speciation, yet little is known about the patterns of molecular evolution in these genes within avian species. This thesis is focused on identifying reproductive genes under positive selection and analyzing their function in songbirds, the largest and most diverse suborder of modern birds. Using existing bioinformatic approaches and published genomic data of 14 songbird species, we have first constructed 12000 groups of orthologous genes and detected significant traces of recurrent positive selection within 385 of them. Using proteomic data, this genome wide set of genes was then filtered to obtain genes expressed within songbird spermatozoa and fluids from the female reproductive tract. Within spermatozoa 22 out of 940 expressed genes were positively selected, while female fluids were found to be more conserved, as only 6 out of 529 expressed genes have shown traces of positive selection. We have then computed the enrichment of gene ontology terms within the positively selected genes. The enriched terms suggest evolutionary pres- sures acting on spermatozoa cytoskeleton, molecular motors and energetic metabolism, highlighting the importance of sperm morphology and swimming speed. Furthermore, the enrichment results...
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Význam vitaminu D a jeho metabolitů v reprodukci živočišných organismů
Červenka, Jiří
Vitamin D is considered to be a group of molecules that have many functions in animal organisms. The best known of these is the key role in calcium and phosphorus homeostasis and regulation of bone mineralization. In recent years, however, many new functions of this vitamin have been discovered, such as the regulation of cell proliferation and differentiation, its influence on the immune system or its function in animal reproduction. This thesis deals with the importance of vitamin D in animal reproduction with an emphasis on livestock. In the literature review, the occurrence of receptors for vitamin D in cells of various types of different tissues of reproductive system, particularly in mammals and birds, and the function of various metabolites mediated by these receptors are discussed in the individual chapters. The thesis includes the design of methodology, which would test the effect of vitamin D on reproduction of the male and female domestic chickens. The hypothesis could verify, whether or not, Rhode Island Red cockerels, that would be fed a diet with a higher vitamin D content would demonstrate better ejaculate parameters and higher fertilization of eggs laid by Rhoade Island White hens inseminated with this semen. Furthemore, a solution is proposed to verify the hypothesis, assuming higher hatchability and lower embryonic mortality in hens fed higher vitamin D feed mixture. The result would be compared with hens and roosters of the same breeds, reared in an environment with the same conditions, fed a vitamin D deficient feed mixture.
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Rab proteins in sperm life
Vojtová, Kristýna ; Páleníková, Veronika (advisor) ; Zelenková, Natálie (referee)
Rab proteins are the largest group of small GTPases. They work as key regulators in the intracellular vesicular transport of cells. This bachelor's thesis contains a literature review of current information on the function of Rab proteins in mammalian spermatozoa. The first part of the work is devoted to their structure, function, cycle, and diseases related to the dysfunction of Rab proteins. The second part is focused on sperm development and maturation linked with specific Rab proteins involved in individual steps during the life of the sperm. Rab proteins are important in cytoskeletal organization and cytokinesis of sperm during spermatogenesis. They participate in the acrosome biogenesis mediated by the Golgi apparatus and the morphological changes of sperm during spermiogenesis. They also play a key role in the acrosome reaction and interaction with the zona pellucida. Due to their necessity in the sperm development and maturation, Rab proteins are proposed as a marker of male fertility, which is summarized in the last part of the thesis. Keywords Rab proteins, GTPases, sperm, spermatogenesis, spermiogenesis, fertilization, infertility
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Proteomic architecture of sperm-egg interactions
Otčenášková, Tereza ; Stopka, Pavel (advisor) ; Petr, Jaroslav (referee) ; Vrbacký, Marek (referee)
Recent advances in proteomic methods provide new insights for biological research including the field of reproductive biology. Determination of the proteomic basis of spermatozoa is pivotal for understanding the complex process of gamete interactions during fertilization such as acrosome reaction. Great differences imposed by postcopulatory sexual selection and phylogeny can be observed regarding the size, shape, and molecular composition of sperm across animal taxa. The first objective of this doctoral thesis is to characterize the protein contents of the acrosome to ascertain its further functional significance in sperm-egg interaction. Also, we aim to investigate the potential relationships between sperm protein composition and sperm morphology diversification, risk of sperm competition, and species phylogenetic background. Wild-caught males from natural populations of species of Mus musculus musculus, Apodemus flavicollis, Microtus arvalis (order Rodentia), Acrocephalus palustris, Chloris chloris, Phylloscopus collybita, Cinclus cinclus, Hirundo rustica, and Taeniopygia guttata from a captive population (order Passeriformes) were subject to the analyses. Nano-liquid chromatography with tandem mass spectrometry was applied as the main methodological approach in this thesis. Our data implicate...
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Ezrin-Radixin-Moesin (ERM) proteins: The link between tetraspanin web and cytoskeleton in gametes
Picková, Jana ; Frolíková, Michaela (advisor) ; Lánská, Eva (referee)
Ezrin, which belongs to the ERM protein family along with radixin and moesin, plays an important role in linking membrane proteins to the actin cytoskeleton. In sperm, ezrin was described so far in bovine and humans, where it probably contributes in actin polymerization during capacitation. During the acrosome reaction, actin plays a significant role in relocation of protein from the inner acrosomal membrane to the equatorial segment, which is an essential process for successful fertilization. One of the proteins that relocates to the equatorial segment, the site of initiation of gamete fusion, is protein CD9. This protein probably stabilizes protein interactions between sperm and oocyte during gamete fusion. In this diploma thesis, we focused on the role of ezrin in linking the CD9 protein to the actin cytoskeleton in mouse sperm. Using indirect immunofluorescence, we detected ezrin, CD9 and actin in acrosome intact mouse sperm. The co-localization of these proteins in the apical acrosomal region suggests their interactions. However, this was not confirmed by our co-immunoprecipitation experiments. Nevertheless, in the apical acrosomal region we also detected EWI-2 protein, which could act as linker between CD9 and ezrin. In this thesis, we also investigated changes in levels of active...
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The role of LINC complex in male germinal cells
Kmoníčková, Věra ; Komrsková, Kateřina (advisor) ; Knop, Filip (referee)
LINC (linker of the nucleoskeleton and cytoskeleton) complex is substantial for the overall function of any nuclear cell. It is a bridge between the cytoplasmic and nuclear structures which mediates transmission of mechanical forces generated on the cytoplasmic side. The main objective of this thesis is the function of distinct variants of the LINC complexes in mammalian male germinal cells throughout their development. The nuclear facing side of the LINC complex is a key player in homolog pairing and rapid chromosome movements during meiosis. The cytoplasmic facing side is necessary for the sperm head formation, proper acrosome and nucleus attachment. Evenly, another complex is essential for the head-to-tail coupling as without this one the sperm cells are found decapitated. If the subunits of the LINC complex are defective, males are afflicted with different kinds of infertilities, which nowadays is one of the important issues of our society. Many things about the role and structure of the LINC complex has been discovered due to modern technologies. These up to date findings are summarized and discussed on the following pages.
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Sperm maturation process in fishes (review)
KŘIŠŤAN, Jakub
The main aim of this thesis was to review the current knowledge in the field of fish sperm maturation (a process where immature spermatozoa acquire the potential to respond to motility-activating factors) and the urogenital system structure in relation to this maturation.
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Aspekty spermatologického vyšetření nativního bovinního ejakulátu
Weberová, Gabriela
In this bachelor thesis was described the reproductive system of a bull, hormonal regulation, sperm production and sperm, was also focused on the collection and sampling methods ejaculate. Work dealt with of studies of morphologically abnormal sperm and their influence on the fertility of bulls. At morphological defects been described primary and secondarily changed spermatozoa. Examination of native ejaculate was divided into microscopical, microbiological and special. At the end of this bachelor thesis was given the chapter on automated scoring systems ejaculates. Of those systems been described system for evaluating ejaculate CASA and flow cytometry.
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Frekvence výskytu morfologických změn spermií hřebců v Zemském hřebčinci Tlumačov s.p.
Jakubčíková, Simona
Morphological evaluation of sperm has a long history and is an essential element analysis of semen, which provides breeders invaluable information to assess the health status of animal and its potential fertility. An important role is played by the percentage of healthy sperm due to abnormally developed. This value plays an important role in the usability of quality in breeding stallions. Stallion sperm intended for artificial insemination breeding mares in native form may not contain more than 40 % of defective sperm and the total amount of their activity should not be below 60 %. In the case of benefits intended for deep freezing is allowed only 20 % pathological forms of sperm. Activity selected for cryopreservation of semen should not fall below 80 %. The topic of the thesis was to determine the frequency of morphologic sperm defects in a group of stallions stud farm Tlumačov s.p., included in breeding season for 2013. Sperm morphology examination was performed on 72 samples of ejaculates collected from 12 stallions during the breeding season from May to August. For each stallion sperm activity was recorded of subjective method, immediately after collection, and the correlation was observed with respect to morphological abnormalities of the same sample. To investigate the morphological structure of sperm abnormalities were stained with two methods of cytological stain -- staining of B.T.Farelly and staining of Čeřovský. After staining the preparations were evaluated under a light microscope. Identified defects were divided into 6 categories - defects in the head, acrosome defects, defects of the neck, tail defects, abnormal forms of sperm and immature sperm. We studied a number of normospermia and total sperm pathology also expressed as a percentage. Another part of the analysis was a theoretical comparison of both the staining techniques with respect to suitability for the examination of morphological sperm abnormalities in stallions.
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