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Diversity and Evolution of Short Interspersed Nuclear Elements (SINEs) in Angiosperm and Gymnosperm Species and their Application as molecular Markers for GenotypingKögler, Anja 08 September 2020 (has links)
Short interspersed nuclear elements (SINEs) are small non-autonomous and heterogeneous retrotransposons, widespread in animals and plants and usually differentially propagated in related species resulting in genome-specific copy numbers.
Within the monocots, the Poaceae (sweet grasses) is the largest and economically most important plant family. The distribution of 24 Poaceae SINE (PoaS) families, five of which showing a subfamily structure, was analyzed in five important cereals (Oryza sativa, Triticum aestivum, Hordeum vulgare, Sorghum bicolor, Zea mays), the energy crop Panicum virgatum and the model grass Brachypodium distachyon. The comparative investigation of SINE abundance and sequence diversity within Poaceae species provides insights into their species‐specific diversification and amplification. The PoaS families and subfamilies fall into two length and structural categories: simple SINEs of up to 180 bp and dimeric SINEs larger than 240 bp. Of 24 PoaS families, 20 are structurally related across species, in particular either in their 5′ or 3′ regions. Hence, reshuffling between SINEs, likely caused by nested insertions of full-lengh and truncated copies, is an important evolutionary mechanism of SINE formation. Most striking, the recently evolved homodimeric SINE family PoaS‐XIV occurs exclusively in wheat (T. aestivum) and consists of two tandemly arranged PoaS‐X.1 copies.
Exemplary for deciduous tree species, the evolutionary history of SINE populations was examined in six Salicaceae genomes (Populus deltoides, Populus euphratica, Populus tremula, Populus tremuloides, Populus trichocarpa, Salix purpurea). Four of eleven Salicaceae SINE (SaliS) families exhibit a subfamily organization. The SaliS families consist of two groups, differing in their phylogenetic distribution pattern, sequence similarity and 3’ end structure. These groups probably emerged at different evolutionary periods of time: during the ‘salicoid duplication’ (~ 65 million years ago) in the Salix-Populus progenitor, and during the separation of the genus Salix (~ 45 - 65 million years ago), respectively. Similar to the PoaS families, the majority of the 20 SaliS families and subfamilies share regions of sequence similarity, providing evidence for SINE emergence by reshuffling. Furthermore, they also contain an evolutionarily young dimeric SINE family (SaliS-V), amplified only in two poplar genomes. The special feature of the Salicaceae SINEs is the contrast of the conservation of 5’ start motifs across species and SINE families compared to the high variability of
3’ ends within the SINE families, differing in sequence and length, presumably resulting from mutations in the poly(A) tail as a possible route for SINE elongation. Periods of increased transpositional activity promote the dissemination of novel 3’ ends. Thereby, evolutionarily older motifs are displaced leading to various 3’ end subpopulations within the SaliS families. Opposed to the PoaS families with a largely equal ratio of poly(A) to poly(T) tail SINEs, the SaliS families are exclusively terminated by adenine stretches.
Among retrotransposon-based markers, SINEs are highly suitable for the development of molecular markers due to their unidirectional insertion and random distribution mainly in euchromatic genome regions, together with an easy and fast detection of the heterogeneous SINE families. As a prerequisite for the development of SINE-derived inter-SINE amplified polymorphism (ISAP) markers, 13 novel Theaceae SINE families (TheaS-I - TheaS-VII, TheaS-VIII.1 and TheaS-VIII.2, TheaS-IX - TheaS-XIII) were identified in the angiosperm tree species Camellia japonica. Moreover, six Pinaceae SINE families (PinS-I.1 and PinS-I.2, PinS-II – PinS-VI) were detected in the gymnosperm species Larix decidua. Compared to the SaliS and PoaS families, structural relationships are less frequent within the TheaS families and absent in the PinS families.
The ISAP analysis revealed the genetic identity of Europe’s oldest historical camellia (C. japonica) trees indicating their vegetative propagation from the same ancestor specimen, which was probably the first living camellia on European ground introduced to England within the 18th century. Historical sources locate the native origin of this ancestral camellia specimen either in the Chinese province Yunnan or at the Japanese Gotō Islands. Comparative ISAPs showed no accordance to the Gotō camellia sample pool and appropriate Chinese reference samples were not available. However, the initial experiments demonstrated the potential of ISAP to resolve variations among natural populations.
The ISAP application on angiosperm trees also concerned fast growing Populus clones grown in short rotation coppice plantations for energy production. The species-specific P. tremula ISAP primers might also be applied for the discrimination of hybrid poplar clones involving P. tremuloides genome
portions, since SINEs of these two species are highly related. However, due to lineage-specific SINE evolution during speciation, cross-species applications are generally only successful to limited extent. The analysis of poplar hybrids composed of P. maximowiczii with either P. trichocarpa or P. nigra based on P. tremula ISAP primers showed a strongly reduced resolution.
In forestry, hybrid larch (e.g. Larix × eurolepis) genotypes have to be selected from the offspring of Japanese (Larix kaempferi) and European larch (Larix decidua) crosses, as they exhibit superior growth rates compared to the parental species. Initial ISAP-based examinations of European larch genotypes provided less polymorphic banding patterns, probably resulting from general high levels of synteny and collinearities reported for gymnosperm species. Hence, the ISAP was combined with the AFLP technique to the novel marker system inter-SINE-restriction site amplified polymorphism (ISRAP). The amplicons originating from genomic regions between SINEs and EcoRI cleavage sites were visualized with the sensitive capillary gel electrophoresis. The ISRAP assays, based on EcoRI adapter primers combined with two different SINE-derived primers, resulted in a sufficient number of polymorphic peaks to distinguish the L. decidua genotypes investigated. Compared to ISAPs, the ISRAP approach provides the required resolution to differentiate highly similar larch genotypes.
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Vliv triaxiální deformace kameniva na vlastnosti betonu / The influence of triaxial deformation of aggregates on properties of concreteFójcik, Tomáš January 2009 (has links)
This diploma work takes focus in elastic modulus of unbound granular aggregates, which was determined by repeat load triaxial test and in deformation behaviour of unbound granular aggregates - elastic and plastic deformation. It was examine the propriety of this aggregate for its service as underlying granular material in pavement. Further, there was observed the influence of elastic modulus of unbound granular aggregates on concrete characteristics - compressive and bending strength. Finally, it was observed the influence of individual fractions of aggregates on its elastic modulus and strength of concrete.
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Buněčné mechanizmy regulace kanálu TRPA1 / Cellular mechanisms of TRPA1 channel regulationBarvíková, Kristýna January 2020 (has links)
TRPA1 is a thermosensitive ion channel from the ankyrin subfamily of Transient Receptor Potential (TRP) receptors. These proteins play essential roles in the transduction of wide variety of environmental and endogenous signals. TRPA1, which is abundantly expressed in primary nociceptive neurons, is an important transducer of various noxious and irritant stimuli and is also involved in the detection of temperature changes. Similarly to other TRP channels, TRPA1 is comprised of four subunits, each with six transmembrane segments (S1-S6), flanked by the cytoplasmic N- and C-terminal ends. In native tissues, TRPA1 is supposed to be regulated by multiple phosphorylation sites that underlie TRPA1 activity under physiological and various pathophysiological conditions. Using mutational approach, we predicted and explored the role of potential phosphorylation sites for protein kinase C in TRPA1 functioning. Our results identify candidate residues, at which phosho-mimicking mutations affected the channel's ability to respond to voltage and chemical stimuli, whereas the phospho-null mutations to alanine or glycine did not affect the channel activation. Particularly, we identify the serine 602 within the N-terminal ankyrin repeat domain 16, the substitution of which to aspartate completely abolished the TRPA1...
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Specifika práce s dlouhodobými klienty na lince důvěry Senior telefon / Specifics of working with long-term clients of the "Senior telefon" helplineMundok Nitschová, Aneta January 2020 (has links)
(in English) The dissertation focuses on working with long-term clients of the "Senior telefon" helpline. It elaborates on the specifics of working with the clients who use the helpline repeatedly compared to other users. The thesis is based on theoretical knowledge sourced from professional literature and statistics, as well as on the internal regulations, documents and methodological materials of the "Senior telefon" helpline. The empirical part analyses selected documents that deal with the potential of working with long-term clients, with the aim to compare the findings with the existing Methodology of working with long-term clients of the "Senior telefon" helpline.
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Affinity Based Capture of Circulating Tumour Cells Using Designed Ankyrin Repeat Proteins (DARPins) in a Microfluidic SystemSpåre, Emil January 2021 (has links)
Designade ankyrinupprepningsproteiner (DARPiner) är små, mycket stabila antikroppsmimetiska proteiner. I det här projektet användes anti-EpCAM-DARPiner tillsammans med mikrofluidik för att avgära om de kunde fånga upp HCT116-celler mer effektivt än anti-EpCAM-antikroppar. Ytorna på insidan av mikroffluidikkanaler förändrades genom bindning av N-γ-maleimidobutyryl-oxysuccinimidester (GMBS) och merkaptopropyltrietoxysilan (MPTES) för anti-EpCAM-antikroppar och GMBS och (3-aminopropyl)trietoxysilan (APTES) för DARPiner. Båda kanaltyperna testades genom inflöde av cancerceller och helblod blandat med cancerceller. Ingen effektiv och konsekvent celluppfångst åstadkoms trots att det visades att antikropparna och DARPinerna kunde binda till cellerna direkt och att test med fluorescenta DARPiner och antikroppar visade att ytförändringskemin var fungerande. Slutsatsen blev att de mest troliga orsakerna till misslyckandena var att ytförändringskemin påverkade proteinernas bindningsförmåga negativt eller att proteinerna bands till kanalernas yta i fel riktning. DARPiner är fortfarande intressanta för tillämpningar inom mikrofluidik, men vidare förbättring av det experimentella protokollet behövs. / Designed ankyrin repeat proteins (DARPins) are small and highly stable antibody mimetics. In this project, anti-EpCAM DARPins were used in conjunction with microfluidics to determine if they could capture HCT116 cells more effectively than anti-EpCAM antibodies. The inside surfaces of microfluidic chips were modified using N-γ-maleimidobutyryl-oxysuccinimide ester (GMBS) and mercaptopropyltriethoxysilane (MPTES) for anti-EpCAM antibodies, and surface modifications for anti-EpCAM DARPins were made using GMBS and (3-aminopropyl)triethoxysilane (APTES). Both chip types were tested using cancer cells and whole blood mixed with cancer cells. No effective and consistent cell capture was achieved, despite the antibodies and DARPins being shown to be able to bind to the cells directly and tests with fluorescently labelled DARPins and antibodies showing that the surface modification chemistry used was functional. It was concluded that the most likely causes of the failures were surface modifications interfering with the binding ability of the proteins, or improper orientation of the bound proteins. The DARPin remains a protein of interest for microfluidic applications, but further changes and optimisation of the experimental protocol is necessary.
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Home in Hardship : Exploring how United Nations professionals negotiate constructions of home in and between hardship settingsThomas, Alexander January 2021 (has links)
There is a general recognition within the social sciences that extensive mobility challenges how we perceive the notion of home. With this idea as its starting point, this thesis explores how situations of hardship impact the ways in which mobile professionals negotiate and construct their homes. The actor-network theory (ANT) has been used as the means to explore the interactions between the people who inform this study and the multidimensional characteristics of the hardship setting. Through individual, open-ended interviews, the research draws upon the experiences of five international civil servants from the United Nations (UN) system of organizations who are assigned to hardship duty stations. Applying ANT to the empirical material drew the attention to the identification of five principal entities (or actors) that come into play in the negotiation of home construction, namely the civil servant, [in]security, mobility, ownership and social relations. The influence of the various nonhuman actors on home construction varied according to the individual and their transnational ties and professional status – those with family nuclei tended to situate their homes in terms of territoriality, whereas for others, factors such as privacy, materiality and social interaction weighed more heavily in the act of creating home.
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The Co-chaperones FKBP51 and PP5 Control Nuclear Receptor Phosphorylation and AdipogenesisStechschulte, Lance A. 21 August 2013 (has links)
No description available.
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Algorithms to Resolve Large Scale and Complex StructuralVariants in the Human GenomeHayes, Matthew 23 August 2013 (has links)
No description available.
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InvasiveJames, Lindsey Taylor 08 May 2018 (has links)
No description available.
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Aberrant DNA Replication at an Ectopic Chromosomal Site in Human CellsChen, Xiaomi 27 April 2011 (has links)
No description available.
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