Biology Commons^™

The Conservation Genetics Of Two Emydid Turtles: Emydoidea Blandingii And Malaclemys Terrapin, Charlotte Lizana Petre

Master's Theses

Conservation of turtles is complicated by their sensitivity to habitat degradation and overexploitation. I used microsatellites and standard population genetic analyses to explore genetic diversity, population structure, paternity and demographic history in two emydid turtles that are currently experiencing threats to their survival. The Blanding’s turtle, Emydoidea blandingii, has experienced habitat fragmentation throughout its range, and this study focuses on a population in Massachusetts where hatchlings from one population are being translocated to establish a new population. I found evidence of multiple paternity within clutches and found no significant reduction in genetic diversity when comparing the source population and …

Empirical Demonstration Of Environmental Sensing In Catalytic Rna: Evolution Of Interpretive Behavior At The Origins Of Life, Niles Lehman, Tess Bernhard, Brian C. Larson, Andrew J.N. Robinson, Christopher C.B. Southgate

Chemistry Faculty Publications and Presentations

Background: The origins of life on the Earth required chemical entities to interact with their environments in ways that could respond to natural selection. The concept of interpretation, where biotic entities use signs in their environment as proxy for the existence of other items of selective value in their environment, has been proposed on theoretical grounds to be relevant to the origins and early evolution of life. However this concept has not been demonstrated empirically.

Results: Here, we present data that certain catalytic RNA sequences have properties that would enable interpretation of divalent cation levels in their environment. …

The Role Of Mir-34a In Inhibition Of Prostate Tumor Growth In The Bone And Induction Of Autophagy, Sanchaika Gaur

Dissertations and Theses (Open Access)

Prostate cancer (PCa) is the second leading cause of cancer-related deaths in men in the United States, with most deaths occurring from bone metastasis. Several new therapies have been FDA approved for bone-metastatic PCa, but patient survival has only marginally improved due to therapy resistance, which often arises from constitutive activation of compensatory signaling pathways. This dissertation work focused on a mechanistic understanding of how cross talk between tyrosine kinase receptors contributes to therapy resistance, and how this may be overcome by downregulating expression of these receptors. In PCa cell lines and xenograft models, I demonstrated that activation of IGF-1R …

Role Of Phosphorylation Of Focal Adhesion Kinase At Tyrosine 861 In Prostate Cancer Metastasis, Tanushree Chatterji

Dissertations and Theses (Open Access)

Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that mediates interactions between the extracellular matrix and intracellular signaling pathways critical in promoting numerous cellular functions including adhesion, proliferation, survival and migration. Most FAK functions result from phosphorylation by Src family kinases, which trigger numerous signaling cascades. Overexpression of FAK is associated with metastasis in many solid tumors, including prostate cancer. Hence, understanding the mechanisms by which FAK is regulated in prostate cancer will better elucidate its role in prostate cancer metastasis. Work in this dissertation tested the hypothesis that altered phosphorylation of FAK is critical for cell migration and …

Targeting Cox-2 And Rank In Aggressive Breast Cancers: Inflammatory Breast Cancer And Triple-Negative Breast Cancer, Monica Elizabeth Reyes

Dissertations and Theses (Open Access)

Inflammatory breast cancer (IBC) and triple-negative breast cancer (TNBC) are two highly aggressive breast cancer subtypes associated with a poor outcome. Despite sensitivity to current treatment, these breast cancers subtypes have a high recurrence rate and proclivity to metastasize early. The aggressiveness of IBC and TNBC have been linked to CSCs and epithelial to mesenchymal transition (EMT), which are critical features of breast cancer progression and metastasis. The clinical challenge faced in the treatment of IBC and TNBC is finding a treatment strategy to target the cancer stem-like (CSC) population to block metastasis. Cyclooxygenase-2 (COX-2) and receptor activator of nuclear …

Targeting Cox-2 And Rank In Aggressive Breast Cancers: Inflammatory Breast Cancer And Triple-Negative Breast Cancer, Monica E. Reyes

Dissertations and Theses (Open Access)

Inflammatory breast cancer (IBC) and triple-negative breast cancer (TNBC) are two highly aggressive breast cancer subtypes associated with a poor outcome. Despite sensitivity to current treatment, these breast cancers subtypes have a high recurrence rate and proclivity to metastasize early. The aggressiveness of IBC and TNBC have been linked to CSCs and epithelial to mesenchymal transition (EMT), which are critical features of breast cancer progression and metastasis. The clinical challenge faced in the treatment of IBC and TNBC is finding a treatment strategy to target the cancer stem-like (CSC) population to block metastasis. Cyclooxygenase-2 (COX-2) and receptor activator of nuclear …

Small Mammals Matter? Linking Plant Invasion, Biotic Resistance, And Climate Change In Post-Fire Plant Communities, Rory Charles O'Connor

Theses and Dissertations

The introduction and establishment of exotic species can profoundly alter ecosystems. Two exotic species drastically changing the landscape of deserts in western North America are Bromus tectorum L. and Bromus rubens L. Through the buildup of biomass and slow decomposition rates in deserts these two exotic annual grasses can alter fire regimes that change the plant and animal community dynamics in the ecosystems. To better understand the ecological mechanisms that could restrict or alter the patterns of invasive plant establishment we established a replicated full factorial experiment in the Great Basin and Mojave Desert. The combinations of factors being manipulated …

Cloning And Expression Of A Tobacco Stearoyl-Acp Desaturase Gene Sbip24 And Its Interaction With Sabp2 In Sa Pathway, Amin J. Ferdous

Electronic Theses and Dissertations

Salicylic acid binding protein 2 (SABP2) that converts methyl salicylate to salicylic acid (SA) plays an obligatory role in the SA-mediated disease resistance pathway in plants. SABP2 interacts with SBIP24 in a yeast two-hybrid screening. SBIP24 belongs to the stearoyl-acyl carrier protein-desaturase protein family. To biochemically characterize the SBIP24, it was cloned from tobacco leaves using RT-PCR and expressed in E. coli. Recombinant SBIP24 was affinity purified using Ni-NTA chromatography. RT-PCR was performed to determine the role of SABP2 in modulating the expression SBIP24. TMV infected transgenic C3 (control tobacco plant containing empty silencing vector) and 1-2 (SABP2-silenced) …

Identification, Cloning, And Expression Of Tobacco Responsive To Dehydration Like Protein (Rd22), Sbip-355 And Its Role In Sabp2 Mediated Sa Pathway In Plant Defense, Hanadi Abdulaali Almazroue

Electronic Theses and Dissertations

Abscisic acid (ABA) induces RD22, responsive to dehydration stress gene. Salicylic acid (SA) has been the focus of research due to its role against pathogens and abiotic stress. Interaction between ABA and SA signaling pathways is still poorly understood. SA-Binding Protein 2 (SABP2) converts methyl salicylate to SA. An attempt was made to identify proteins that interact with SABP2 using a yeast 2-hybrid screening. Several interactors were identified. One of them, SA-Binding Protein 2 Interacting Protein-355 (SBIP-355), showed high homology to RD22. Bioinformatic approaches showed that SBIP-355 contains a BURP domain. Phylogenetic analysis reveals that SBIP-355 clustered into the …

Functional Morphology Of The Connective Tissue Of The Clavicular System Of The Domestic Cat, Felis Catus, Amanda N. Cooper

Honors Capstones

No abstract provided.

Phylogenomics And Historical Biogeography Of The Gooseneck Barnacle Pollicipes Elegans, Sergio Andres Marchant Rojas

All Dissertations

This dissertation explores the systematics, biogeography, and genomics of the gooseneck barnacle Pollicipes elegans, a marine crustacean of the tropical Eastern Pacific. In Chapter 1, I provide a broad framework for my research by introducing and focusing on the long-­‐standing debate of the mechanisms behind the latitudinal gradient in species diversity, which provided the initial motivation for using Pollicipes elegans as a model system to study the mechanisms leading to genetic differentiation and speciation in tropical regions. In Chapter 2, I examine the genetic structure, infer patterns of connectivity across the warm tropical waters of the eastern Pacific, and reconstruct …

The Interaction Of Aeolian And Fluvial Processes In Dry Washes On The Colorado Plateau, Usa, Beau Jensen Walker

Theses and Dissertations

In the past decade there has been a call for integrated studies that examine the interaction of fluvial and aeolian processes (Belnap et al., 2011; Bullard and Livingstone, 2002). In this study, we examined the role of land-use, weather, and soil type on the flux of aeolian material into dry washes on the Colorado Plateau in central Utah, USA, and western Colorado, USA. Our goal was to quantify the impact of individual deposition and erosion events by correlating weather and land-use data with a combination of measurement methods including dust collection via dust traps, GPS surveying, and close-range photogrammetry. Our …

Role Of Epistasis In Alzheimer's Disease Genetics, Mark T. Ebbert

Theses and Dissertations

Alzheimer's disease is a complex neurodegenerative disease whose basic etiology and genetic structure remains elusive, despite decades of intensive investigation. To date, the significant genetic markers identified have no obvious functional effects, and are unlikely to play a role in Alzheimer's disease etiology, themselves. These markers are likely linked to other genetic variations, rare or common. Regardless of what causal mutations are found, research has demonstrated that no single gene determines Alzheimer's disease development and progression. It is clear that Alzheimer's disease development and progression are based on a set of interactions between genes and environmental variables. This dissertation focuses …

Relationship Between Stream Velocity & Depth And Snail Size Distribution & Density Of The Balcones Elimia, Elimia Comalensis (Pilsbry, 1890) (Gastropoda: Pleuroceridae) In Comal Springs, Texas, Kathryn E. Perez, Russell L. Minton, Scott A. Reese, David M. Haye

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Pleurocerid snails are important components of aquatic ecosystems and the majority of species are threatened or endangered. This study describes aspects of the life-history of Elimia comalensis, specifically population density in relationship to water velocity and depth, and seasonal change. Also examined are spatial segregation of different E. comalensis age groups and the relationship of snail size (proxy for age) to 110w, depth, and seasonal change. The study was carried out in the lotic portion of spring run 3, Coma! Springs, New Braunfels, Texas, by quadrat sampling at 10 in intervals from the spring head to Landa Lake in Fall. …

Preliminary Transcriptome Analysis And Homeobox Gene Isonlation For Tomocerus Minor (Entomobryomorpha: Tomoceridae), Alejandro Alaniz

Theses and Dissertations - UTB/UTPA

Collembola, or “springtails,” are small, edaphic arthropods classified as Entognatha; a group traditionally included as part of Hexapoda and sister-group to the true insects. However, some genetic studies suggest that they may instead have derived from a separate crustacean lineage rather than from a proto-Insecta lineage. The unique abdominal structures that develop on the collembolan ventral abdomen appear to be appendicular in origin – atypical to the canonical, appendage-less insect abdomen ground plan. I developed culture and embryo fixation protocols for; and sequenced and analyzed a multi-stage embryo transcriptome for Tomocerus minor (Collembola: Entomobryomorpha). This analysis annotated 14,417 distinct genes, …

Metamorphosis Of Limulus Polyphemus Trilobite Larvae: Role Of Chemical And Structural Cues, Competency, And The Cost Of Delayed Metamorphosis, Stephanie Marie Kronstadt

Theses and Dissertations

Many marine and estuarine arthropods exhibit complex life cycles that include planktonic larval stages and benthic juvenile and adult phases. Chemical and structural cues associated with juvenile habitats often induce settlement and metamorphosis, thereby shortening the duration of the larval phase. These cues can trigger metamorphosis only after larvae reach competency, or developmental maturity. The point at which larvae reach this competency period and the ability to retain competency is highly species specific. Once competency is attained, a decrease in the time to metamorphosis (TTM) can decrease dispersal potential but may increase the chance of settling in a suitable habitat. …

Decontamination Protocols For Watercraft And Wildland Firefighting Equipment In Preventing The Spread Of Invasive Quagga (Dreissena Rostriformis Bugensis) And Zebra (Dreissena Polymorpha) Mussels, Ashlie Watters

UNLV Theses, Dissertations, Professional Papers, and Capstones

Quagga and zebra mussels (Dreissena rostriformis bugensis and Dreissena polymorpha) are two invasive species introduced via ballast water discharged by large oceanic cargo ships to the North American Great Lakes in the late 1980s. Once established, the mussels spread quickly. In January 2007, D. rostriformis bugensis was discovered in Lake Mead, NV-AZ, and in that same year, mussels were confirmed further south on the Colorado River in Lakes Mojave and Havasu. Dreissenids clog water intake pipes, water filtration systems, and electric generating plants. The mussels also ruin boat motors, damage recreational equipment, and once established in the reservoir, routine maintenance …

Differential Response By Bronzed Cowbirds To Songs Of Potential Hosts In The Lower Rio Grande Valley Of Texas, Mary J. Janecka, Timothy Brush

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

How bronzed cowbirds (Molothrus aeneus) find nests to parasitize is poorly known, especially whether they use host vocalizations as sources of information about nest location and status. We conducted 120 point-count surveys, followed by broadcasts of host songs, at Santa Ana National Wildlife Refuge in the Lower Rio Grande Valley of Texas in 2008 and 2009. Bronzed cowbirds responded to songs of potential host species by flying toward the source of the playback as single females or males or multiple females and males. Bronzed cowbirds responded in greater numbers to the songs of oriole species (Icterus) …

Establishment And Spread Of A Single Parthenogenic Genotype Of The Mediterranean Arundo Wasp, Tetramesa Romana, In The Variable Climate Of Texas, John A. Goolsby, John F. Gaskin, Daniel V. Tarin, Alan E. Pepper, Don C. Henne, Allan Auclair, Alexis Racelis, Kenneth R. Summy, Patrick J. Moran, Donald B. Thomas

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

As part of a biological control program for the invasive weed, Arundo donax L., several genotypically unique populations of the parthenogenetic stemgalling wasp, Tetramesa romana Walker (Hymenoptera: Eurytomidae), from Spain and France were released in an infested riparian zone along the Rio Grande from Brownsville to Del Rio, TX. An adventive population of the wasp of unknown origin with limited distribution in Texas was also discovered, evaluated, and released as part of the program. More than 1.2 million wasps representing the mixture of genotypes were aerially released from 2009 to 2011. Wasps dispersed from their original release locations and now …

Population Genetics, Distributions And Phenology Of Bombus Latreille, 1802 And Xylocopa Latreille, 1802 (Hymenoptera: Apidae), Amber Dawn Tripodi

Graduate Theses and Dissertations

This work addresses multiple knowledge gaps in bee ecology, population health and phylogeography in order to provide insights into the changing distributions of native bees. A comparison of Arkansas bumble bee records mirrors range-wide surveys, with records of stable species (Bombus bimaculatus Cresson, 1863 and B. impatiens Cresson, 1863) increasing three-fold, and records of the declining B. pensylvanicus (DeGeer, 1773) dropping to 60% of historical levels. However, nationally-recommended conservation-genetics tools did not mirror these results on a regional level. Stable and declining species had equivalent genetic diversity in samples from Arkansas and Tennessee (H_S range: 0.46-0.63). Diploid males, …

Bacteriophage Host-Range Expansion To Include Two Strains Of Clostridium Sporogenes, Kevin K. Crown

Biology ETDs

Bacteriophages are viruses that infect bacteria, which have been used to treat bacterial infections in people for decades. They are also now being used as FDA approved preservatives as a means to prevent the growth of spoiling bacteria in many ready-to-eat foods. Bacteriophages tend to infect a very narrow range of bacterial hosts, some only a single sub-strain. When used for therapeutics or food treatment however, it is desirable to use phages that are promiscuous in their host range. This has led to attempts to broaden the host range of the most useful phages. By passaging phages in co-cultures of …

A Morphological Phylogenetic Analysis And Taxonomic Revision Of The Millipede Family Atopetholidae (Chamberlin) (Diplopoda: Spirobolida) With Descriptions Of New Species And The Conservation Status Of Comanchelus Chihuanus (Chamberlin 1947) (Diplopoda: Spirobolida: Atopetholidae), A Species Of Concern, Michael F. Medrano

Biology ETDs

The taxa of family Atopetholidae Chamberlin 1918 occurring in the southwestern US and Mexico, including Baja California, are revised with new records and species from collections that have never been evaluated. Five new genera, Aculeulus, Bajabolus, Choixulus, Pinnaulus and Tamaulus and twenty new species, Aculeulus monicae, Arinolus anahiae, Arinolus sequoiaensis, Arinolus shelleyi, Atopetholus lowreyi, Atopetholus milleri, Atopetholus westi, Bajabolus bernadinoensis, Bajabolus lapazensis, Choixulus valdezi, Eurelus alisonae, Eurelus isaiasi, Eurelus marisae, Pinnaulus fieldsi, Tamaulus brantleyae, Tamaulus justini, Tamaulus maribelleae, Tamaulus miae, Tamaulus wardae and Watichelus sheari are described using morphological data and 18 synonyms are proposed for a total fauna of …

Community Ecology, Climate Change And Ecohydrology In Desert Grassland And Shrubland, Matthew Daniel Petrie

Biology ETDs

This dissertation explores the climate, ecology and hydrology of Chihuahuan Desert ecosystems in the context of global climate change. In coming decades, the southwestern United States is projected to experience greater temperature-driven aridity, possible small decreases in annual precipitation, and a later onset of summer monsoon rainfall. These changes may have profound consequences for ecological systems in the Chihuahuan Desert, which are intensely water-limited and respond to even small pulses of moisture availability. The first chapter (Chapter 2) compares change in the properties of monsoon season precipitation from 1910-2010 in the northern Chihuahuan Desert region to local variability in monsoon …

Bridging Structure And Function In Semi-Arid Ecosystems By Integrating Remote Sensing And Ground Based Measurements, Dan J. Krofcheck

Biology ETDs

The Southwestern US is projected to continue the current significant warming trend, with increased variability in the timing and magnitude of rainfall events. The effects of these changes in climate are already evident in the form of multi-year droughts which have resulted in the widespread mortality of woody vegetation across the region. Therefore, the need to monitor and model forest mortality and carbon dynamics at the landscape and regional scale is an essential component of regional and global climate mitigation strategies, and critical if we are to understand how the imminent state transitions taking place in forests globally will affect …

Aret: A Novel Regulator Of Alternative Splicing In The Flight Muscle Transcripts In Drosophila Melanogaster, Sandy Thi Oas

Biology ETDs

Drosophila melanogaster has been used as a model organism for understanding muscle development. Drosophila flight and jump muscles are distinct functionally and biochemically. This distinction is due to differentially expressed genes and differentially spliced mRNA transcripts. The exact mechanism of alternative splicing in somatic muscles is not well characterized. Aret was previously shown to be a transcriptional repressor, and has been implicated in splicing regulation based upon literature analysis and preliminary work. This study aims to define the regulatory role of Aret and the impact of alternative splicing on determining muscle diversification and fiber choice. We indicate the importance of …

Spatial Patterns Of Zooplankton Distribution And Abundance In Relation To Phytoplankton, Fish Catch And Some Water Quality Parameters At Shirati Bay, Lake Victoria-Tanzania, Revania K. Waya, Samwel M. Limbu, Godfrey W. Ngupula, Chacha J. Mwita, Yunus D. Mgaya

Tanzania Journal of Science

Spatial patterns and abundance of zooplankton in aquatic habitats are important determinants for production of fish species, invertebrates and availability of phytoplankton. Weekly monitoring for zooplankton abundance was conducted in Shirati Bay, Lake Victoria, to explore their spatial patterns in relation to phytoplankton, fish catch and some water quality parameters. The vertical distribution of zooplankton was generally higher close to the bottom as compared to surface waters of the lake. Zooplankton vertical distribution positively correlated with water transparency (r = 0.680, p = 0.011). The horizontal abundance of zooplankton was not significantly different amongst the three stations (p = 0.5143). …

Analysis Of Body Shapes Among Barbus Trimaculatus, Barbus Paludinosus And Barbus Jacksonii (Actinopterygii: Cyprinidae) From Malagarasi And Pangani River Basins Based On Geometric Morphometric Method, Chacha J. Mwita, B.G. Kamugisha

Tanzania Journal of Science

This study analyzed variability in body shapes among the small Barbus species of the family Cyprinidae currently occurring in the Malagarasi and Pangani River basins years after uplift of the east African topology. Fish specimens were collected from Songati, Muumbara and Nyamagoma within the Malagarasi River basin; Hale and Pangani fall located on Pangani River. It was found that although the landmarks were placed at the same anatomical regions, significant body shapes variations existed. The relative warps analysis for Barbus trimaculatus and Barbus jacksonii populations from Malagarasi and Pangani wetlands revealed intra-locality variations as for populations from other African countries. …

An Efficient Algorithm To Explore Liquid Association On A Genome-Wide Scale, Tina Gunderson, Yen Yi Ho

Faculty Publications

Background: The growing wealth of public available gene expression data has made the systemic studies of how genes interact in a cell become more feasible. Liquid association (LA) describes the extent to which coexpression of two genes may vary based on the expression level of a third gene (the controller gene). However, genome-wide application has been difficult and resource-intensive. We propose a new screening algorithm for more efficient processing of LA estimation on a genome-wide scale and apply its use to a data set. Results: On a test subset of the data, the fast screening algorithm achieved >99.8 agreement with …

The Lineage-Specific Evolution Of Aquaporin Gene Clusters Facilitated Tetrapod Terrestrial Adaptation, Roderick Nigel Finn, François Chauvigné, Jón Baldur Hlidberg, Christopher P. Cutler, Joan Cerdà

Biology: Faculty Publications

A major physiological barrier for aquatic organisms adapting to terrestrial life is dessication in the aerial environment. This barrier was nevertheless overcome by the Devonian ancestors of extant Tetrapoda, but the origin of specific molecular mechanisms that solved this water problem remains largely unknown. Here we show that an ancient aquaporin gene cluster evolved specifically in the sarcopterygian lineage, and subsequently diverged into paralogous forms of AQP2, -5, or -6 to mediate water conservation in extant Tetrapoda. To determine the origin of these apomorphic genomic traits, we combined aquaporin sequencing from jawless and jawed vertebrates with broad taxon assembly of …

Stem Nematode Counteracts Plant Resistance Of Aphids In Alfalfa, Medicago Sativa, Ricardo A. Ramirez, John M. Stark

Biology Faculty Publications

Plants are exploited by a diverse community of insect herbivores and phytopathogens that interact indirectly through plant-mediated interactions. Generally, plants are thought to respond to insects and pathogens through different defensive signaling pathways. As plants are selected for resistance to one phytophagous organism type (insect vs. pathogen) in managed systems, it is not clear how this selection may affect community interactions. This study examined the effect of nematode-resistant varieties on aphid (Acyrthosiphon pisum) suppression, and then determined how infection by the stem nematode, Ditylenchus dipsaci, mediated ecological effects on aphids and on plant defense proteins. Four alfalfa (Medicago sativa) varieties …