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Epigenetics was a term first coined to understand how cells with the same genetic make up can differentiate into various cell types. Elegant research over the past 30 years has shown that these mechanisms include heritable marks such as DNA methylation and histone modifications along with stable expression of non- coding RNAs. Within the realm of epigenetics is a phenomenon known as genomic imprinting. Imprints are marks that distinguish the maternal from the paternal chromosomes in the form of methylation. Methylation marks can influence transcript expression, resulting in only one allele being expressed. One imprinted domain is the Kcnq1 domain located on chromosome 11p15.5 in humans and chromosome 7 in the mouse. This domain is thought to be under the control of a paternally expressed long noncoding RNA (ncRNA) Kcnq1ot1. The Kcnq1ot1 ncRNA is expressed on the paternal chromosome due to a differentially methylation region located within its promoter. The promoter is methylated on the maternal allele thus inhibiting ncRNA expression, whereas the promoter is unmethylated on the paternal allele. In the placenta, a most of the genes located within a one mega-basepair region are exclusively expressed from the maternal chromosome, whereas the transcripts on the paternal chromosome are silenced by the ncRNA. The placenta seems to follow the classic idea of an imprinted domain. However, in the embryo and more specifically, in the embryonic heart, this is not the case. In the embryonic heart, only a 400kb region is restricted to maternal expression. In addition, one the genes, Kcnq1, starts out expressed exclusively from the maternal allele in early development but switches to biallelic expression during mid-gestation. The purpose of my research is to determine the underlying complexities that are involved in the regulation of transcripts within the Kcnq1 domain. This involves the Kcnq1 gene itself, which has been shown to transition from mono- to biallelic expression during mid-gestation and the Kcnq1ot1 ncRNA per se. I hypothesize that regulation by the Kcnq1ot1 ncRNA is not occurring in a uniform manner in the embryo; rather, the amount of regulation by the ncRNA is dependent on the developmental stage and specific tissue. In addition, this regulation involves complex interactions between enhancers, insulators and other regulatory elements to control the amount of silencing by the Kcnq1ot1 ncRNA. First, through a series of experiments looking at the Kcnq1 promoter, the mechanism of Kcnq1 paternal expression was determined. It was confirmed that Kcnq1 becomes biallelic during mid-gestation in the heart. Bisulfite mutagenesis and methylation sensitive chromatin immunoprecipitation were used to test the hypothesis that the Kcnq1 promoter was methylated in early development and then lost its methylation mark. However, a lack of methylation disproved this mechanism of paternal Kcnq1 activation. Rather, chromosome conformation capture (3C) determined that the Kcnq1 promoter interacts in a tissue-specific manner with regions within the domain that have enhancer activity. The role of the ncRNA within our system was also investigated. Interestingly, when Kcnq1ot1 allelic expression was profiled throughout development in heart, it transitioned to biallelic expression during heart development but remained monoallelic in the liver and brain. Several possibilities could account for this phenomenon, including loss of promoter methylation and/or an alternative transcript start site. Both of these options were explored using bisulfite mutagenesis and 5' RACE. However, the Kcnq1ot1 promoter region retained its methylation mark even after the maternal transcript was turned on, disproving this idea. Rather, a maternal specific transcript was found in the heart to start downstream of the CpG islands. Lastly, to gain a better understand of the Kcnq1ot1 ncRNA, experiments were carried out on a mutant mouse in which a truncated form of the ncRNA was transmitted paternally; this is dubbed the "Kterm" mouse. Unexpectedly, Kcnq1 still followed the same mono- to biallelic transition as seen in the wild-type, whereas the head and body counterparts from the same stage embryos were biallelic for Kcnq1. Also, the immediate upstream genes, Cdk1nc and Slc22a18, lost their mono-allelic expression in neonatal heart, liver and brain when the Kterm mutation was transmitted. This suggested that Kcnq1ot1 did not function as a silencer for Kcnq1 paternal expression in the heart, but rather had an alternative and previously unknown function. From qRT-PCR, 3C and ChIP assays, it was determined that the Kcnq1ot1 ncRNA plays a role in regulating Kcnq1 gene expression in the heart by limiting its interaction to specific cis-acting enhancers. When the ncRNA was absent, the Kcnq1 promoter interacted with non-native sites along the domain, possibly causing the increase in transcript expression. This phenomenon was specific to the heart and was not seen in other tissues. These findings showed that Kcnq1 paternal expression is the result of strong developmental and tissue specific enhancers. Chromatin interactions in cis put a strong enhancer in contact with the Kcnq1 promoter to increase its expression in later development. In addition, a truncation mutation model identified a key role for the Kcnq1ot1 ncRNA in regulating Kcnq1 expression. Instead of regulating the imprinting status of Kcnq1, the ncRNA regulates the amount of Kcnq1 transcript being produced in the heart by regulating chromatin interactions. Finally, these studies identified a maternally expressed Kcnq1ot1 transcript whose role in heart development is still not fully understood. Taken together, these findings support a model where an inhibitory factor(s) silence the paternal Kcnq1 transcript and maternal Kcnq1ot1 transcript and in later development, this factor is released allowing for expression and chromatin interactions to occur. / Molecular Biology and Genetics

Delia Chiaro (2010) describes humor in two broad categories: referential and verbal. The former focuses on the meaning of a story or event and the humor embedded within. In the case of the latter, idiosyncratic features such as word play displays humorous undertones. This Master’s thesis examines oral text transformation to another language via transcription. The transcripts themselves consist of 10 minutes of the 2012 Presidential debate between François Hollande and Nicolas Sarkozy and 10 minutes of a monologue presented by French animator Cyrille de Lasteyrie. Both transcripts are linked by the commonality of humor and exhibit the two categories previously outlined. Additional attention will be given to the translation challenges that arose such as: transferring the overall meaning of each idea, maintaining as much of the humor within the text as possible and conveying each speaker’s style. This study aims to provide future translators guidance in their translation endeavors by pinpointing scholarly research and discussing the various translator techniques implemented in overcoming challenges such as metaphors and collocations.

The objective of this study is to examine the impact of students accessing Algebra 1 in the 8th grade on their science course-taking patterns in high school in a large district in the Mid Atlantic of the United States. This is an important question because many studies have shown that Algebra 1 is a "gatekeeper" course (Adelman, 1999, 2006) but there has not been much research around the impact of who has taken Algebra 1 by 8th grade and what science courses they took as a result of having access to that particular course (Xin Ma, 2009). The data will be supplied by the school district of the last two cohorts of graduating seniors who were in the district from the seventh grade on, so the analysis can be conducted on those who were subject to the same opportunities and policies. The demographic information that will be requested are: Free/Reduced Meal students (FRMS) as a proxy for socio-economic status (SES), gender, race, English as a Second Language (ESOL) level, Special Education (SPED), what grade the students took Algebra, and the science classes they took while they were in high school. The research questions will be analyzed using JMP, a statistics program supplied by Virginia Tech to see if there are any significant differences in which groups of students took Algebra 1 by 8th grade and what kinds of science courses they took. The major findings were that more White and Asian students, and higher SES students accessed Algebra 1 by 8th grade and were enrolled in more rigorous science classes in their high school career than their Black, Hispanic, low SES, Special Education or English Language peers. The results of this study could inform large school districts about the impact of Algebra 1 by 8th grade on students' science course-taking patterns and promote conversations about their policies they create about access to critical courses. / Doctor of Education / The objective of this study is to examine the impact of students accessing Algebra 1 in the 8th grade on their science course-taking patterns in high school in a large district in the Mid Atlantic of the United States. This is an important question because many studies have shown that Algebra 1 is a "gatekeeper" course (Adelman, 1999, 2006) but there has not been much research around the impact of who has taken Algebra 1 by 8th grade and what science courses they took as a result of having access to that particular course (Xin Ma, 2009). The major findings were that more White and Asian students, and higher SES students accessed Algebra 1 by 8th grade and were also enrolled in more rigorous science classes in their high school career than their Black, Hispanic, low SES, Special Education or English Language peers. The results of this study could inform large school districts about the impact of Algebra 1 by 8th grade on students' science course-taking patterns and promote conversations about their policies they create about access to critical courses. The research could be used by school leaders as context for when they examine the participation of students in their upper level science classes. It could also be used by school counselors to better communicate with families about the importance of mathematics preparation and readiness and the impact of those on other college track courses.

This study aimed to investigate the use of accommodation of assertive utterances (AUs) in the conversations of 49 girls aged 5;0-13;1. Based on the findings of earlier research that the use of such language is more closely related to age than to gender, it was predicted speakers would accommodate their use of and response to assertive utterances as a result of their partner's age. Naturalistic language from these speakers was collected over a year, and evidence of accommodation was observed in all speakers. Fewer AUs were used with younger speakers compared to older ones, and those used with younger girls were more likely to be produced with the sole purpose of controlling the hearer's behaviour. In addition, AUs were more likely to be complied with, or accepted, when they were produced by older girls. Given what is known about the types of language used by powerful/powerless individuals, it appears that these speakers consider age to be an indicator of status. A particularly interesting finding was that it was the age of a speaker in relation to other members of the conversation that influenced their use of and response to AUs, rather than the age of the speaker alone.

The past decades are characterized by various efforts to provide complete sequence information of genomes regarding various organisms. The availability of full genome data triggered the development of multiplex high-throughput assays allowing simultaneous measurement of transcripts, proteins and metabolites. With genome information and profiling technologies now in hand a highly parallel experimental biology is offering opportunities to explore and discover novel principles governing biological systems. Understanding biological complexity through modelling cellular systems represents the driving force which today allows shifting from a component-centric focus to integrative and systems level investigations. The emerging field of systems biology integrates discovery and hypothesis-driven science to provide comprehensive knowledge via computational models of biological systems.<br><br> Within the context of evolving systems biology, investigations were made in large-scale computational analyses on transcript co-response data through selected prokaryotic and plant model organisms. CSB.DB - a comprehensive systems-biology database - (http://csbdb.mpimp-golm.mpg.de/) was initiated to provide public and open access to the results of biostatistical analyses in conjunction with additional biological knowledge. The database tool CSB.DB enables potential users to infer hypothesis about functional interrelation of genes of interest and may serve as future basis for more sophisticated means of elucidating gene function. The co-response concept and the CSB.DB database tool were successfully applied to predict operons in Escherichia coli by using the chromosomal distance and transcriptional co-responses. Moreover, examples were shown which indicate that transcriptional co-response analysis allows identification of differential promoter activities under different experimental conditions. The co-response concept was successfully transferred to complex organisms with the focus on the eukaryotic plant model organism Arabidopsis thaliana. The investigations made enabled the discovery of novel genes regarding particular physiological processes and beyond, allowed annotation of gene functions which cannot be accessed by sequence homology. GMD - the Golm Metabolome Database - was initiated and implemented in CSB.DB to integrated metabolite information and metabolite profiles. This novel module will allow addressing complex biological questions towards transcriptional interrelation and extent the recent systems level quest towards phenotyping. / Die vergangenen Jahrzehnte waren gekennzeichnet durch umfangreiche Bemühungen, die Genomsequenz verschiedener Organismen vollständig zu entschlüsseln. Die Verfügbarkeit vollständiger genomischer Daten löste die Entwicklung von modernen Hochdurchsatzmethoden aus, welche die gleichzeitige Messung von verschiedenen Transkripten, Proteinen und Metaboliten erlauben. Mittels genomischer Informationen und Hochdurchsatztechnologien erlaubt eine hoch parallelisierte experimentelle Biologie die Erforschung von Gesetzmäßigkeiten, welchen biologischen Systemen zugrunde liegen. Das Verständnis biologischer Komplexität durch Modellierung zellulärer Systeme repräsentiert die treibende Kraft, welche heutzutage den Element-zentrierten Focus auf integrative und ganzheitliche Untersuchungen lenkt. Das sich entwickelnde Feld der Systembiologie integriert Entdeckungs- und Hypothesen-getriebene Wissenschaft um ein umfangreiches Wissen durch Computermodelle biologischer Systeme bereitzustellen.<br><br> Im Kontext der sich neu entwickelnden Systembiologie investierte ich in umfangreiche Computeranalysen zur Transkript Co-Response bezüglich ausgewählter prokaryotischer und pflanzlicher eukaryotischer Organismen. CSB.DB - a comprehensive systems-biology database - (http://csbdb.mpimp-golm.mpg.de/) wurde initiiert, um freien Zugang zu den biostatistischen Ergebnissen als auch zu weiterem biologischem Wissen zu bieten. Die Datenbank CSB.DB ermöglicht potentiellen Anwendern die Hypothesengenerierung bezüglich der funktionalen Wechselbeziehungen von Genen von Interesse und kann zukünftig die Grundlage für einen fortgeschrittenen Weg der Zuordnung von Genfunktionen darstellen. Unter Verwendung chromosomaler Distanzen und Transkript Co-Response konnte das Konzept und CSB.DB angewandt werden, um bakterielle Operons in Escherichia coli erfolgreich vorherzusagen. Darüber hinaus werden Beispiele gezeigt, die andeuten, dass die Transkript Co-Response Analyse eine Identifizierung differentieller Promoteraktivität in verschiedenen experimentellen Bedingungen ermöglicht. Das Co-Response Konzept wurde, mit dem Schwerpunkt auf die eukaryotische Modellpflanze Arabidopsis thaliana, erfolgreich auf komplexere Organismen angewandt. Die durchgeführten Untersuchungen ermöglichten die Identifizierung neuer Gene hinsichtlich physiologischer Prozesse und darüber hinaus die Zuweisung von Genfunktionen, welche nicht durch Sequenzhomologie ermöglicht werden kann. GMD - The Golm Metabolome Database - wurde initiiert und in CSB.DB implementiert, um Metaboliten Informationen als auch Metaboliten Profile zu integrieren. Dieses neue Modul ermöglicht die Ausrichtung auf komplexere biologische Fragen und erweitert die derzeitige systembiologische Fragestellung in Richtung Phänotypus-Zuordnung.

Softwood is the predominant form of land plant biomass in the Northern hemisphere, and is among the most recalcitrant biomass resources to bioprocess technologies. The white rot fungus Phanerochaete carnosa has been isolated almost exclusively from softwoods, while most other known white-rot species, including Phanerochaete chrysosporium, were mainly isolated from hardwoods. Accordingly, it is anticipated that P. carnosa encodes a distinct set of enzymes and proteins that promote softwood decomposition. To elucidate the genetic basis of softwood bioconversion by P. carnosa, its genome was sequenced and transcriptomes were evaluated after growth on wood compared to liquid medium. Results indicate that P. carnosa differs from P. chrysosporium in the number and expression levels of genes that encode lignin peroxidase (LiP) and manganese peroxidase (MnP), two enzymes that modify lignin present in wood. P. carnosa has more genes for MnP with higher expression levels than LiP, while the reverse has been observed for P. chrysosporium. The abundances of transcripts predicted to encode lignocellulose-modifying enzymes were then measured over the course of P. carnosa cultivation on four wood species. Profiles were consistent with decay of lignin before carbohydrates. Transcripts encoding MnP were highly abundant, and those encoding MnP and LiP featured significant substrate-dependent response. Since differences in modes of lignin degradation catalyzed by MnP and LiP could affect the ability of each to degrade lignin from different types of wood, their activity on various hardwoods and softwoods were tested. Results suggest that MnP degrades softwood lignin more effectively than hardwood lignin, consistent with high levels of this enzyme in P. carnosa.

Gene-fusions are a prevalent class of genetic variants that are often employed as cancer biomarkers and therapeutic targets. In recent years, high-throughput sequencing of the cellular genome and transcriptome have emerged as a promising approach for the investigation of gene-fusions at the DNA and RNA level. Although, large volumes of sequencing data and complexity of gene-fusion structures presents unique computational challenges. This dissertation describes research that first addresses the bioinformatics challenges associated with the analysis of the massive volumes of sequencing data by developing bioinformatics pipeline and more applied integrated computational workflows. Application of high-throughput sequencing and the proposed bioinformatics approaches for the breast and ovarian cancer study reveals unexpected complex structures of gene-fusions and their functional significance in the onset and progression of cancer. Integrative analysis of gene-fusions at DNA and RNA level shows the key importance of the regulation of gene-fusion at the transcription level in cancer.

Genetics is among the most rewarding fields of biology for the theoretically inclined, offering both room and need for modeling approaches in the light of an abundance of experimental data of different kinds. Many aspects of the field are today understood in terms of physical and chemical models, joined by information theoretical descriptions. This thesis discusses different mechanisms and phenomena related to genetics, employing tools from statistical physics along with experimental biomolecular methods. Five articles support this work. Two articles deal with interactions between proteins and DNA. The first one reports on the properties of non-specific binding of transcription factors proteins in the yeast Saccharomyces cerevisiae, due to an effective background free energy which describes the affinity of a single protein for random locations on DNA. We argue that a background pool of non-specific binding sites is filled up before specific binding sites can be occupied with high probability, thus presenting a natural filter for genetic responses to spurious transcription factor productions. The second article describes an algorithm for the inference of transcription factor binding sites for proteins using a realistic physical model. The functionality of the method is verified on a set of known binding sequences for Escherichia coli transcription factors. The third article describes a possible genetic feedback mechanism between human cells and the ubiquitous Epstein-Barr virus (EBV). 40 binding regions for the major EBV transcription factor EBNA1 are identified in human DNA. Several of these are located nearby genes of particular relevance in the context of EBV infection and the most interesting ones are discussed. The fourth article describes results obtained from a positional autocorrelation analysis of the human genome, a simple technique to visualize and classify sequence repeats, constituting large parts of eukaryotic genomes. Applying this analysis to genome sequences in which previously known repeats have been removed gives rise to signals corroborating the existence of yet unclassified repeats of surprisingly long periods. The fifth article combines computational predictions with a novel molecular biological method based on the rapid amplification of cDNA ends (RACE), coined 5’tagRACE. The first search for non-coding RNAs encoded in the genome of the opportunistic bacterium Enterococcus faecalis is performed here. Applying 5’tagRACE allows us to discover and map 29 novel ncRNAs, 10 putative novelm RNAs and 16 antisense transcriptional organizations. Further studies, which are not included as articles, on the monitoring of secondary structure formation of nucleic acids during thermal renaturation and the inference of genetic couplings of various kinds from massive gene expression data and computational predictions, are outlined in the central chapters. / QC 20110316

Softwood is the predominant form of land plant biomass in the Northern hemisphere, and is among the most recalcitrant biomass resources to bioprocess technologies. The white rot fungus Phanerochaete carnosa has been isolated almost exclusively from softwoods, while most other known white-rot species, including Phanerochaete chrysosporium, were mainly isolated from hardwoods. Accordingly, it is anticipated that P. carnosa encodes a distinct set of enzymes and proteins that promote softwood decomposition. To elucidate the genetic basis of softwood bioconversion by P. carnosa, its genome was sequenced and transcriptomes were evaluated after growth on wood compared to liquid medium. Results indicate that P. carnosa differs from P. chrysosporium in the number and expression levels of genes that encode lignin peroxidase (LiP) and manganese peroxidase (MnP), two enzymes that modify lignin present in wood. P. carnosa has more genes for MnP with higher expression levels than LiP, while the reverse has been observed for P. chrysosporium. The abundances of transcripts predicted to encode lignocellulose-modifying enzymes were then measured over the course of P. carnosa cultivation on four wood species. Profiles were consistent with decay of lignin before carbohydrates. Transcripts encoding MnP were highly abundant, and those encoding MnP and LiP featured significant substrate-dependent response. Since differences in modes of lignin degradation catalyzed by MnP and LiP could affect the ability of each to degrade lignin from different types of wood, their activity on various hardwoods and softwoods were tested. Results suggest that MnP degrades softwood lignin more effectively than hardwood lignin, consistent with high levels of this enzyme in P. carnosa.