Genetics and Genomics Commons^™

What’S In A Gene: Undergraduates’ Ideas And Misconceptions About Gene Function, Justin M. Levaughn

Theses and Dissertations--Science, Technology, Engineering, and Mathematics (STEM) Education

The purpose of this study was to field test a two-tiered instrument including multiple-choice and short answer tasks to assess college students’ ideas and level of understanding in genetics. The instrument was constructed from previously tested assessment tasks and findings from the current research literature. Ninety-seven freshmen enrolled in a biology lab course were surveyed. Test validity and reliability were measured using Chronbach coefficients. Multiple-choice and short answer responses were analyzed using descriptive statistics to identify frequencies of answer selections. Written responses were independently evaluated using a five-point scoring rubric by three researchers to identify common misconceptions revealed in students’ …

Ecology Of Two Reintroduced Black Bear Populations In The Central Appalachians, Sean Mccarthy Murphy

Theses and Dissertations--Animal and Food Sciences

Reintroduced populations are vulnerable to demographic and environmental stochasticity, deleterious genetic effects, and reduced population fitness, all of which can increase extinction probability. Population viability is principle to determining the status of reintroduced populations and for guiding management decisions. To attempt to reestablish black bear (Ursus americanus) populations in the central Appalachians, two reintroductions using small founder groups occurred during the 1990s in the Big South Fork area along the Kentucky-Tennessee border (BSF) and in the Jefferson National Forest along the Kentucky-Virginia border (KVP). My objectives were to estimate demographic and genetic parameters, and to evaluate long-term viability …

Understanding The Molecular Mechanisms Underlying Rsv1 Mediated Resistance To Smv In Soybean, Mohammed Ali Ahmed Eid

Theses and Dissertations--Plant Pathology

Like humans, viral diseases also affect plants. Of these, viruses belonging to the potyvirus genus are the most prolific. The potyvirus soybean mosaic virus (SMV) is an important pathogen of the crop plant soybean. SMV causes mosaic symptoms (yellow areas alternate with dark green areas on the leaves of the plant) and can affect yield by reducing seed quality. Few cultivars from soybean can resist different SMV strains. To understand soybean defense mechanisms to SMV, I identified soybean proteins that interact with the helper component protease (HC-Pro) of SMV, which also functions as the suppressor of host RNA silencing and …

Investigation Into The Cell Wall And Cellulose Biosynthesis In Model Species And In The C4 Model Plant Setaria Viridis, Mizuki Tateno

Theses and Dissertations--Plant and Soil Sciences

A uniform feature of all plant cells is the presence of a cell wall. The cell wall functions in facilitating directional expansion and is therefore important for cell shape and morphogenesis. All plant cell walls contain cellulose microfibrils embedded in a network of polysaccharides, lignin and protein. Cellulose is evolutionarily conserved and is made by all plants as well as other members of various taxonomic kingdoms. From a human perspective, the field of renewable energy has had an ever increasing interest in using the cell wall for production of renewable platform chemicals and fuels. However, the biosynthesis of these components …

Population Genetic Structure Of Necturus Maculosus In Central And Eastern Kentucky, Mason Owen Murphy

Theses and Dissertations--Biology

Population structure is influenced by extrinsic factors, such as landscape architecture and dispersal barriers. Lotic network architecture is known to constrain ecological, demographic and evolutionary processes, including population genetic structure. I assessed the population structure of a widespread aquatic salamander, Necturus maculosus, across three river basins in central and eastern Kentucky. I examined the role of network architecture, anthropogenic barriers, and spatial scale on patterns of population structure. I also provided a review of N. maculosus capture methods and offer an improved trap design. I identified significant structuring between the combined Licking/Kinniconick basin and the Kentucky River basin, with …

Characterization Of Somatically-Eliminated Genes During Development Of The Sea Lamprey (Petromyzon Marinus), Stephanie A. Bryant

Theses and Dissertations--Biology

The sea lamprey (Petromyzon marinus) undergoes programmed genome rearrangements (PGRs) during early development that facilitate the elimination of ~20% of the genome from the somatic cell lineage, resulting in distinct somatic and germline genomes. To improve our understanding of the evolutionary/developmental logic of PGR, we generated computational predictions to identify candidate germline-specific genes within a transcriptomic dataset derived from adult germline and the embryonic stages encompassing PGR. Validation studies identified 44 germline-specific genes and characterized patterns of transcription and DNA loss during early embryogenesis. Expression analyses reveal that several of these genes are differentially expressed during early embryogenesis …

Expression Of Zinc Fingers And Homeoboxes 2 (Zhx2) And Zhx2 Target Genes In Multiple Tissues Of Wild-Type And Zhx2 Knockout Mice, Minen Al-Kafajy

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

The Spear lab has had a long-standing interest in gene regulation in the liver during development and disease. Several years ago, these studies identified a novel transcriptional regulator called Zinc fingers and homeoboxes 2 (Zhx2), which is a member of a small family that includes Zhx1 and Zhx3. All Zhx proteins contain two amino-terminal C2-H2 zinc fingers and four or five carboxy-terminal homeodomains. Previous studies indicate that Zhx proteins can form homodimers and heterodimers with each other.

Zhx2 regulates numerous hepatic genes, including alpha-fetoprotein (AFP) and H19. Genes controlling lipid and cholesterol homeostasis are also regulated by …

The Role Of Sox4 In Regulating Choroid Fissure Closure And Retinal Neurogenesis, Wen Wen

Theses and Dissertations--Biology

The development of the vertebrate eye is tightly controlled by precise genetic regulations. From a single ocular primordium to bilateral eyes with complex structures and cell types, it requires intensive proliferation and migration for cells in both the ectoderm and mesoderm to accomplish ocular morphogenesis, and during this process cell differentiation and interaction takes place to establish the complex composition of ocular cell types and cellular connections. Genetic defects can lead to severe abnormalities in eye morphogenesis and cell differentiation during ocular development. A tremendous amount of work has been done to identify both intrinsic and extrinsic factors that regulate …

The Effects Of Manufactured Nanomaterial Transformations On Bioavailability, Toxicity And Transcriptomic Responses Of Caenorhabditis Elegans, Daniel L. Starnes

Theses and Dissertations--Plant and Soil Sciences

In recent decades, there has been a rapid expansion in the use of manufactured nanoparticles (MNPs). Experimental evidence and material flow models predict that MNPs enter wastewater treatment plants and partition to sewage sludge and majority of that sludge is land applied as biosolids. During wastewater treatment and after land application, MNPs undergo biogeochemical transformations (aging). The primary transformation process for silver MNPs (Ag-MNPs) is sulfidation, while zinc oxide MNPs (ZnO-MNPs) most likely undergo phosphatation and sulfidation. Our overall goal was to assess bioavailability and toxicogenomic impacts of both pristine, defined as-synthesized, and aged Ag- and ZnO-MNPs, as well as …