Spelling suggestions: "subject:"repeated sequences""
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The Role of Terminal Repeat Sequences in the Preservation of the Ends of the Adenovirus Genome / Role of ITRs in the Preservation of the Ends of AdenovirusLippe, Roger 03 1900 (has links)
The requirement for identical inverted terminal repeats (ITRs) for viral viability and the role of internal viral sequences in the specification of the sequences of the termini were investigated. The viral strains used in this study were a variant Ad2 strain Ad2 (mac) and the wild type Ad5 strain which was very similar to the former one in sequence except at the extreme end of the terminal repeat. A hybrid virus (sub54), obtained by recombination between Ad2 (mac) and Ad5, derived the left 41-51% of its genome from Ad2 (mac) and the right 59-49% from Ad5. The identity of the termini was determined by Southern blotting analysis using 32p end labeled oligocleoxynucleotides. Analysis of the sub54 isolate indicated that both Ad2 (mac) and Ad5 ITRs were present. Plaque purification of sub54 demonstrated that viruses with non identical terminal sequences were viable and allowed their characterization. This analysis also indicated that Ad5 ITRs are converted to Ad2 (mac) ITRs possibly as a result of repair of the ends to yield viruses with identical termini. A model involving replication and emphasizing the importance of panhandle formation as a replicative intermediate is proposed. These results also indicated a possible role of the internal sequences of adenovirus in the selection and maintenance of serotype specific ITRs. The preference for Ad2 (mac) termini observed during repair of the ends of sub54 may be related to the origin of the genes coding for the adenoviral polymerase and/or the terminal protein both of which were derived from Ad2 (mac). Further investigation would be required to determine whether these replicative proteins are actually involved in ITR conversion. Transformation of Escherichia coli with a DNA preparation from sub54 infected rat embryo cells resulted in the isolation of the plasmid pFG154. This plasmid contained the entire adenovirus genome with an Ad2 (mac) ITR at the "left" terminus covalently linked to an Ad5 ITR at the "right". Analysis of the viral progeny generated upon transfection of mammalian cells with pFG154 indicated that the Ad2 (mac) ITRs were very efficiently converted to Ad5 termini. These results, although apparently contradictory to those initially obtained from the plaque purification of sub54, may be explained by an ITR repair model which is specific for infectious circles. / Thesis / Master of Science (MS)
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Characterization of mutations in the terminal repeats and capsid proteins of the adeno-associated virus type-2Opie, Shaun Rueben, January 2003 (has links)
Thesis (Ph. D.)--University of Florida, 2003. / Title from title page of source document. Includes vita. Includes bibliographical references.
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Varijabilnost mikrosatelitskih lokusa X hromozoma u populaciji Vojvodine / Genetic variability of X chromosome microsatellite loci in population of VojvodinaVapa Dušan 29 January 2016 (has links)
<p>Kratki uzastopni ponovci predstavljaju klasu mikrosatelitskih segmenata DNK, rasprostranjenih širom genoma čoveka. Građeni su od uzastopno ponavljajućih sekvenci dužine 2-6 parova nukleotida. Zahvaljujući različitom broju ponavljanja repetitivne jedinice, većina mikrosatelitskih markera pokazuje visok stepen polimorfizma dužine, koji je moguće ispitati primenom tehnike lančane reakcije polimeraze. Pored utvrđivanja spornih srodničkih odnosa, analiza X hromozom mikrosatelitskih markera može se uspešno koristiti i u oblastima kriminalistike, humane identifikacije, populaciono-genetičkim i demografskim istraživanjima i dr. Cilj istraživanja je izrada populacione studije, iz koje će se izračunati broj i frekvencija alela, struktura i frekvencija haplotipova, utvrditi vrednosti relevantnih statističkih parametara, oceniti mogućnost primene analize X-STR markera u slučajevima iz oblasti medicinske kriminalistike, humane identifikacije i veštačenja spornih srodničkih odnosa u populaciji Vojvodine. Istraživanjem je obuhvaćeno 200 odraslih, međusobno nesrodnih osoba. Izolacija DNK materijala iz krvnih mrlja vršena je Chelex metodom, a amplifikacija dobijenih uzoraka DNK metodom PCR, uz korišćenje komercijalnog Mentype® Argus X-12 PCR Amplification Kit – a. Razdvajanje i detekcija dobijenih fragmenata izvršeno je kapilarnom elektroforezom GeneScan i Genotyper programom. Statististička obrada rezultata izvršena je pomoću Arlequin i GENEPOP programa. Za vizuelizaciju interpopulacionih genetičkih odnosa, upotrebljen je program POPTREE2 i koordinatna analiza (Principal Coordinate Analysis - PCoA). Dobijeni rezultati ukazuju da se analiza ispitivanih X-STR markera može uspešno primeniti u slučajevima iz oblasti medicinske kriminalistike, humane identifikacije i veštačenja spornih srodničkih odnosa u populaciji Vojvodine, kao i da mogu poslužiti kao osnova za dalja istraživanja u populacionogenetičkim, antropološkim, demografskim i drugim oblastima.</p> / <p>Short tandem repeats (STR) represent a class of microsatellites, widely spread throughout the human genome, consisting of tandemly repeated sequences of 2-6 bp. Related to variation in the number of repeat unit displayed, most of microsatellites show a high degree of length polymorphism, investigated by the PCR techniques. The aim of this research is to create a population study, which will be used to calculate allele and haplotype frequencies, determine the value of relevant statistical parameters and assess the possibility of applying X-STR markers analysis in the fields of forensics, human identification and kinship testing. The study included 200 unrelated adults. DNA isolation was performed by Chelex method and DNA amplification by PCR, using commercial Mentype Argus X-12 PCR Amplification Kit. Separation and detection of fragments was obtained by capillary electrophoresis using Gene Scanand Genotyper program. Statistical analysis of the result was performed using Arlequin and GENEPOP program. For visualization of inter population genetic distances POPTREE2 program and coordinate analysis (PCoA) was used. The results show that the analysis of X-STR markers can be successfully applied in the field of forensics, human identification and kinship testing in the population of Vojvodina, as well as to serve as a basis for further research in population genetic, anthropological, demographic and other scientific areas.</p>
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Approche cytogénomique de l'évolution des séquences répétées : cas des satellites et des gènes ribosomiques au sein du genre Mus. / Cytogenomic approach of the evolution of repetitive sequences in the genus Mus : the case of satellite DNA and ribosomal clusters.Cazaux, Benoite 06 December 2011 (has links)
L'étude comparative de l'architecture des génomes mammaliens a révélé l'association des séquences répétées et des réarrangements. Cette thèse porte sur la dynamique et le rôle dans les remaniements de deux types de séquences répétées: les clusters ribosomiques et les satellites. Ces séquences sont analysées par une approche cytogénomique (FISH, CO-FISH) dans le genre Mus connu pour sa diversité chromosomique, et pour lequel les phylogénies moléculaires et chromosomiques sont disponibles.1) La distribution chromosomique des clusters ribosomiques, établie chez 19 espèces, a permis de reconstruire les états ancestraux des clusters. Cette analyse montre que les clusters (24%) sont associés à des points de cassures, mais présentent également une grande labilité en l'absence de réarrangements. De plus, une forte association entre les clusters et les centromères est mise en évidence. 2) Le sous-genre Mus se caractérise par un caryotype très conservé excepté chez une sous-espèce de la souris domestique (M. musculus domesticus), qui est connue pour son extraordinaire radiation chromosomique impliquant les séquences satellites du centromère. Afin de rechercher les spécificités génomiques responsables de ce patron d'évolution contrasté, la dynamique évolutive des séquences satellites a été analysée chez 11 taxons. Révélant des différences qualitatives entre taxons, cette étude a permis de proposer un scénario évolutif de ces séquences. Toutefois, aucune des caractéristiques étudiées (composition, orientation) n'est propre à M. m. domesticus, et ne permet de rendre compte de sa plasticité chromosomique. De même, chez cette dernière, aucun lien entre la quantité de séquences satellites et la fréquence d'implication des chromosomes dans les réarrangements n'est mis en évidence.Cette étude confirme que les séquences répétées participent à l'évolution chromosomique, mais ne constituent pas à elles seules l'élément clef de cette dernière. / Comparative analyses of the architecture of mammalian genomes have highlighted the association between repetitive sequences and rearrangements. This thesis focuses on the evolutionary dynamics of two repeat sequences (ribosomal clusters and satellites) and explores their role in chromosomal change. These sequences are analyzed by a cytogenomic approach (FISH, CO-FISH) in the genus Mus that is known for its chromosomal diversity and for which molecular and chromosomal phylogenies are available.1) The chromosomal distribution of ribosomal clusters, established in 19 species, allowed us to reconstruct the ancestral states of clusters. This analysis demonstrated that 24% of clusters were associated with breakpoints, whereas others showed high lability in the absence of rearrangements. Moreover, a strong association between clusters and centromeres was retrieved.2) The subgenus Mus is characterized by a highly conserved karyotype except for one subspecies of the house mouse (M. musculus domesticus), that displays an extraordinary chromosomal radiation involving centromeric satellite sequences. To determine the genomic traits related to this difference in rate, the evolutionary dynamics of satellite sequences was analyzed in 11 taxa. From the qualitative differences evidenced between taxa, an evolutionary scenario of these sequences is proposed. None of the studied features (composition, orientation) of these sequences was found to be specific to M. m. domesticus, and could explain its chromosomal plasticity. Similarly, in the latter, no relationship between satellite sequence quantity and the rearrangement frequency of chromosomes was found.This study confirms that although repeated sequences are involved in chromosomal evolution, they aren't in themselves the key element of the latter.
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