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Full-Text Articles in Life Sciences

Growth, Lipid Production And Biodiesel Potential Of Chromulina Freiburgensis Dofl., An Acidophilic Chrysophyte Isolated From Berkeley Pit Lake, June E. Mohler Mitman Mar 2109

Growth, Lipid Production And Biodiesel Potential Of Chromulina Freiburgensis Dofl., An Acidophilic Chrysophyte Isolated From Berkeley Pit Lake, June E. Mohler Mitman

Graduate Theses & Non-Theses

Microalgae remain a promising, but underdeveloped source of lipids for sustainable biodiesel. Some of the obstacles to cost-effective commercial-scale production have been culture contamination and expensive harvest methods. A chrysophyte isolated from Berkeley Pit Lake and identified as Chromulina freiburgensis, was found to grow rapidly in a pH 2.5 liquid medium and to amass numerous intracellular lipid bodies. This research addresses the scarcity of published knowledge on the topic of chrysophyte species as potential lipid sources for biodiesel. It investigates how growth phase, culture conditions, and harvest timing influence the quantity and composition of lipids produced by this alga ...


A Multivariate Ecological Approach To Delineate Unionid Freshwater Mussel Species, Ava M. Laszlo Dec 2019

A Multivariate Ecological Approach To Delineate Unionid Freshwater Mussel Species, Ava M. Laszlo

Biology Theses

Freshwater mussels represent one of the most imperiled faunal groups on the planet and are critical to freshwater ecosystems. If mussel species are not carefully defined, our conservation plans may miss differences in the habitat needs of different species and the conservation strategies may not be as successful. Because ecological niche models can be used to provide evidence to support similar or dissimilar ecological niches and habitat requirements, I used modelling to forecast suitable habitat for Fusconaia askewi and F. lananensis, two purported threatened Texas species. The modeling results indicated that these species are not ecologically different. Based upon this ...


Oil Preference In Ants And Arthropod Diversity In Urban Environments, Itzel Guzman-Hernandez Dec 2019

Oil Preference In Ants And Arthropod Diversity In Urban Environments, Itzel Guzman-Hernandez

Honors Theses

The success of certain ant species in urban areas is largely unknown. Available food in the environment could affect the composition of ants in urban areas due to a possible relationship between ant physiology and diet. I tested the oil preference of ants as a function of available arthropod prey in urban environments. I hypothesized that as arthropod diversity decreased, ant abundance at oil baits would decrease. Oil is an important nutrient that can affect ant body functions and activities. Ant foraging activities have been found to be affected by lipid depletion. A food source where ants can obtain oil ...


Mammal Species Inventory Using Various Trapping Methods In Zone 4 Of Billy Barquedier National Park, Belize During Rainy Season, Mersady Redding Dec 2019

Mammal Species Inventory Using Various Trapping Methods In Zone 4 Of Billy Barquedier National Park, Belize During Rainy Season, Mersady Redding

Animal Science Undergraduate Honors Theses

Belize is a small country, but it is extremely ecologically diverse. Based on the few studies conducted in Belize, the abundance of mammals is low but diversity is high. Particular findings note the number and identity of species differed between four sites in the Maya Mountains of Belize, indicating that a data set from a single site is not representative of the Neotropical region. Insufficient data is available to estimate current species richness of many areas in Belize, including Billy Barquedier National Park (BBNP). The objective of this study was to explore trapping and documentation methods of terrestrial mammals in ...


The Relationship Between Biofilm Production And Human Respiratory Cell Attachment And Invasion By Acinetobacter Baumannii, Rachel A. Pearson Dec 2019

The Relationship Between Biofilm Production And Human Respiratory Cell Attachment And Invasion By Acinetobacter Baumannii, Rachel A. Pearson

Theses and Dissertations

Acinetobacter baumannii is an opportunistic gram-negative bacterial pathogen that causes many nosocomial infections in immunocompromised individuals. Common infections include catheter-associated urinary tract infections, ventilator-associated pneumonia, skin and soft tissue infections, and bloodstream infections that often lead to septicemia. Increasing multidrug resistance (MDR) in A. baumannii warrants new approaches to understanding its virulence mechanisms and pathogenicity. As a first step in infection, A. baumannii can attach to host cells, providing a surface for the bacteria to grow and perhaps facilitating biofilm formation and subsequent tissue invasion. In this study, we evaluated antibiotic resistance and characterized biofilm formation, attachment, invasion, and surface ...


Integrating Social Dimensions Into Spatial Connectivity Planning For Grizzly Bears, Abigail Sage Dec 2019

Integrating Social Dimensions Into Spatial Connectivity Planning For Grizzly Bears, Abigail Sage

Boise State University Theses and Dissertations

In anthropogenic landscapes, which prevail globally, preserving key habitat corridors or routes between wildlife populations is vital for long-term species persistence. Animals moving through these corridors can encounter a number of barriers, including roads, fences, or other human land-uses. Additionally, people unwilling to cohabitate with wildlife can also kill animals considered nuisances or disturb animals in ways that reduce their fitness. The spatial patterns of human tolerance therefore play an important role in the efficacy of habitat corridors. Although there are large bodies of research on habitat corridors and human attitudes toward wildlife, studies that examine the spatial interaction of ...


Non-Native Leaf Litter Modifies Algal Resources With Effects On Tadpole Growth, Spencer L. Cruz Dec 2019

Non-Native Leaf Litter Modifies Algal Resources With Effects On Tadpole Growth, Spencer L. Cruz

Theses and Dissertations

Leaf litter species play a key role in determining the quality and quantity of algal resources in aquatic ecosystems as a cross-boundary subsidy. The invasion of non-native plant species into forests can alter aquatic resources. I investigated the effects of non-native leaf litter species on algal resources and green frog, Lithobates clamitans, development using a randomized complete block experiment that lasted 288 days. In experimental ponds, I added two non-native and two native leaf litter species in the presence and absence of tadpoles. Early in the experiment, Japanese honeysuckle and Chinese privet decreased periphyton N:P ratios and stimulated tadpole ...


Movements And Behaviors Of Resident And Translocated Northern Map Turtles (Graptemys Geographica) In The Upper Niagara River With Artificial Basking/Nesting Platforms As A Management Strategy, Chelsea L. Moore Dec 2019

Movements And Behaviors Of Resident And Translocated Northern Map Turtles (Graptemys Geographica) In The Upper Niagara River With Artificial Basking/Nesting Platforms As A Management Strategy, Chelsea L. Moore

Biology Theses

Urbanization and degradation of riparian zones has contributed to the decline of fish and wildlife populations throughout the world. Northern Map Turtles (Graptemys geographica) in the upper Niagara River face similar declines due to shoreline development and the concurrent loss of backwater habitats and terrestrial nesting sites. A project was initiated in which basking/nesting platforms were created, and Northern Map Turtles from a Lake Erie population were translocated into the river. Resident and translocated turtles were tracked using biotelemetry and their habitat use, behaviors, and swimming paths were compared. Translocated turtles exhibited homing behavior and had longer home ranges ...


Exploring The Physiology And Evolution Of Hornworts, Tanner A. Robison Dec 2019

Exploring The Physiology And Evolution Of Hornworts, Tanner A. Robison

All Graduate Theses and Dissertations

Plants contain organelles called chloroplasts, which is where photosynthesis takes place. Chloroplasts also contain their own DNA, which is separate from the DNA in the nucleus. This DNA does not change much over evolutionary time, so it can be used to investigate relationships between organisms. Here we created a tool that makes it easier to analyze this chloroplast DNA as well making it easier to share complete chloroplast genomes on public databases. In addition, we also found a mobile element in the chloroplast DNA of a group of ferns, which appears to be driving structural changes in their genomes.


Urban Stream Syndrome And The Presence Of E. Coli In Philadelphia Streams, Eileen Black Nov 2019

Urban Stream Syndrome And The Presence Of E. Coli In Philadelphia Streams, Eileen Black

HON499 projects

In this experiment, water samples were collected from the Pennypack and Wissahickon Creeks as part of an exploratory study on the presence of microbes, particularly Escherichia coli, in urban streams. Contamination by E. coli may indicate that a creek is polluted and suffering from urban stream syndrome. E. coli was found in both creeks, likely due to their locations near a sewage treatment facility and a farm.


The Functional, Ecological, And Evolutionary Morphology Of Sea Lampreys (Petromyzon Marinus), Bradley Morgan Wood Nov 2019

The Functional, Ecological, And Evolutionary Morphology Of Sea Lampreys (Petromyzon Marinus), Bradley Morgan Wood

LSU Doctoral Dissertations

Lampreys (Petromyzontiformes) are jawless vertebrates with an evolutionary history lasting at least 360 million years and are often used in comparisons with jawed vertebrates because some of their morphological aspects, such as the segmented trunk musculature with curved myosepta and a non-mineralized skeleton fibrous skeleton, are thought to resemble the condition of early vertebrates before the evolution of jaws. Although earlier authors studied the morphology of the skeleto-muscular system of the trunk of lampreys, their studies are not detailed and complete enough to allow a functional and biomechanical analysis that is needed as a basis for modeling the mechanics of ...


Engineering Self-Assembling Proteins To Produce A Safe And Effective Vaccine For Porcine Reproductive And Respiratory Syndrome, Ondre H. Harper Oct 2019

Engineering Self-Assembling Proteins To Produce A Safe And Effective Vaccine For Porcine Reproductive And Respiratory Syndrome, Ondre H. Harper

Electronic Thesis and Dissertation Repository

Commercially available vaccines for porcine reproductive and respiratory syndrome virus (PRRSV) provide some control over the virus but none are ideal since they either are not completely safe for use, lack efficacy in promoting long-lasting immunity or provide no protection from heterologous PRRSV strains. Innovative approaches to designing vaccines are being pursued to overcome these drawbacks. One example is the use of nanoparticles to present a dense array of antigenic epitopes to the immune system which can effectively stimulate antibody producing cells (B cells) and T cells, resulting in long-lasting immunity. Here, I genetically fused antigenic epitopes from PRRSV to ...


Equine Hoof Stratum Internum K14+Cd105+ Progenitor Cells: Culture, Characterization, And Model Of Epithelial To Mesenchymal Transition, Qingqiu Yang Oct 2019

Equine Hoof Stratum Internum K14+Cd105+ Progenitor Cells: Culture, Characterization, And Model Of Epithelial To Mesenchymal Transition, Qingqiu Yang

LSU Doctoral Dissertations

For the potential benefit of progenitor cells to be realized in cell-based clinical therapies, it is vital to investigate the mechanism between progenitor cells and abnormal tissue formation. Laminitis is a fatal condition that is often presented by equine hoof inflammation and hoof tissue disarrangement. The persistence of abnormal tissue formation after the resolution of equine laminitis suggests there is progenitor cell compromise. So far, there is limited information about equine hoof progenitor cells and the effects of inflammation on hoof progenitor cells. To pursue a better understanding of both hoof progenitor cell and hoof growth as well as find ...


Tracing Nutrient Sources To Lipid Production In Birds And Insects Using Stable Isotope (Δ13c, Δ2h) Tracers: Implications For Nutritional Physiology Of Migratory Species, Libesha Anparasan Oct 2019

Tracing Nutrient Sources To Lipid Production In Birds And Insects Using Stable Isotope (Δ13c, Δ2h) Tracers: Implications For Nutritional Physiology Of Migratory Species, Libesha Anparasan

Electronic Thesis and Dissertation Repository

Using stable isotope measurements of inert tissues to determine origins and migratory patterns is well established. However, isotopically determining nutritional origins of lipids, the primary fuel of migration, has not been attempted. I explored isotopic links between diet and stored lipids in captive White-throated Sparrows (Zonotrichia albicollis) and true armyworm moths (Mythimna unipuncta) using δ13C and δ2H measurements. Isotopic discrimination between body lipids and diet was established as linear calibration functions. Isotopic uptake following a diet switch in moths was used to trace lipid accumulation over time. Isotopic correlations between breath metabolic by-products of fed and ...


Investigation Of The Mechanisms Governing Carrier Domain Translocation In S. Aureus Pyruvate Carboxylase, Joshua Hakala Oct 2019

Investigation Of The Mechanisms Governing Carrier Domain Translocation In S. Aureus Pyruvate Carboxylase, Joshua Hakala

Dissertations (2009 -)

A central debate in protein biochemistry focuses on the mechanism by which ligands contribute to conformational changes in proteins. Two primary hypotheses describe this process: the induced-fit hypothesis and the conformational ensembles hypothesis. In contrast to the induced-fit hypothesis, the conformational ensembles hypothesis states that the protein pre-exists in multiple conformational states, with ligand binding shifting the equilibrium towards a preferred conformation. The contribution of ligand binding to large-scale conformational changes is particularly relevant to multi-domain “swinging-arm” enzymes, for which pyruvate carboxylase (PC) serves as a well characterized paradigm system. PC catalyzes the ATP-dependent carboxylation of pyruvate to oxaloacetate. The ...


Effects Of Water Table Depth And Edaphic Characteristics On Plant Diversity In A Southern Mississippi Pitcher Plant Bog, Patrick Kirby Oct 2019

Effects Of Water Table Depth And Edaphic Characteristics On Plant Diversity In A Southern Mississippi Pitcher Plant Bog, Patrick Kirby

Master's Theses

This study examined the effects that water table depth and soil characteristics have on plant species richness and species composition within pitcher plant bogs across seasons. Eight piezometers were installed at random distances to monitor long-term water table depth and pressure fluctuations along a ~710-meter line transect traversing upland and bog habitats. Vegetation sampling quadrats (n=128) were set up near each piezometer. Cover data and water table depths were collected in spring and late summer. Soil samples collected from each treatment group were used to obtain soil texture and nutrient data. The summer collection period yielded a total gdiversity ...


The Stability Of Temperate Lakes Under The Changing Climate, Aleksey Paltsev Sep 2019

The Stability Of Temperate Lakes Under The Changing Climate, Aleksey Paltsev

Electronic Thesis and Dissertation Repository

There is a collective prediction among ecologists that climate change will enhance phytoplankton biomass in temperate lakes. Yet there is noteworthy variation in the structure and regulating functions of lakes to make this statement challengeable and, perhaps, inaccurate. To generate a common understanding on the trophic transition of lakes, I examined the interactive effects of climate change and landscape properties on phytoplankton biomass in 12,644 lakes located in relatively intact forested landscapes. Chlorophyll-a (Chl-a) concentration was used as a proxy for phytoplankton biomass. Chl-a concentration was obtained via analyzing Landsat satellite imagery data over a 28-year period (1984-2011) and ...


5 Lipoxygenase's Role In Chondrogenesis Of The Atdc5 Cell Line, Tien My Tran Aug 2019

5 Lipoxygenase's Role In Chondrogenesis Of The Atdc5 Cell Line, Tien My Tran

Seton Hall University Dissertations and Theses (ETDs)

5-Lipoxygenase metabolizes arachidonic acid (AA) to generate leukotrienes (LTs). Leukotrienes are very potent inflammatory mediators that can have negative effects on bone healing and cartilage tissue generation. Recent studies have shown that decreasing 5-lipoxygenase (5-LO) activity during fracture healing accelerates endochondral ossification and decreases healing time in animal fracture models, however, the roles of 5-LO in chondrogenesis is not fully investigated. In this study, we tested the hypothesis that 5-LO inhibition will increase the process of chondrogenesis. The ABT-761 is an N-hydroxyurea analog structurally similar to zileuton, which is a 5-LO enzyme inhibitor, The ATDC5 cell line which is derived ...


The Relative Importance Of Larval And Adult Nutrition In The Isotopic Profile Of The Spermatophore Produced By The Male True Armyworm Moth (Mythimna Unipuncta) (Haworth)., Aida Parvizi Aug 2019

The Relative Importance Of Larval And Adult Nutrition In The Isotopic Profile Of The Spermatophore Produced By The Male True Armyworm Moth (Mythimna Unipuncta) (Haworth)., Aida Parvizi

Electronic Thesis and Dissertation Repository

The wings of true armyworm (Mythimna unipuncta) are metabolically inactive tissue and as their isotopic profiles are determined by resources obtained during larval development, they provide information on natal origin of immigrants. The majority of female immigrants are mated so could the isotopic profiles of spermatophores dissected from her reproductive tract provide information about the natal origin of her mates? However, as spermatophores are produced by metabolically active male accessory glands and could use resources obtained from larval and adult feeding I conducted experiments to determine the relative importance of these two dietary sources on the isotopic profiles of spermatophores ...


The Cost Of Protection: Frost Avoidance And Competition In Herbaceous Plants, Frederick Curtis Lubbe Aug 2019

The Cost Of Protection: Frost Avoidance And Competition In Herbaceous Plants, Frederick Curtis Lubbe

Electronic Thesis and Dissertation Repository

Perennial herbaceous plants in regions that experience winter freezing must survive using belowground structures that can tolerate or avoid frost stress. Soil and plant litter can insulate plant structures from frost exposure, but plants must invest into growth to penetrate through these layers to reach the surface in the spring. The overall goal of my thesis was to test the hypothesis that the protection of overwintering clonal structures by soil or plant litter (frost avoidance) comes at the expense of subsequent reduced growth and competitive ability in absence of freezing stress. I first explored this trade-off with a suite of ...


Understanding Excitation Energy Quenching In Isia, Hui-Yuan Steven Chen Aug 2019

Understanding Excitation Energy Quenching In Isia, Hui-Yuan Steven Chen

Engineering and Applied Science Theses & Dissertations

Cyanobacteria are photoautotrophic organisms that contribute a significant amount of global primary productivity. They are found in freshwater, marine and even some extremely severe environments. Among those environments, iron deficiency is one of the most common stress conditions in cyanobacterial habitats. To survive, cyanobacteria have evolved and developed several strategies to alleviate the damage caused by iron deficiency.

Iron stress-inducible protein (IsiA) is a chlorophyll-binding membrane protein found in cyanobacteria grown in iron-deficient conditions. During the past decades, considerable effort has been put on understanding how IsiA functions to help cyanobacteria survive iron deficiency. It has been reported that IsiA ...


Understanding Excitation Energy Quenching In Isia, Hui-Yuan Steven Chen Aug 2019

Understanding Excitation Energy Quenching In Isia, Hui-Yuan Steven Chen

Engineering and Applied Science Theses & Dissertations

Cyanobacteria are photoautotrophic organisms that contribute a significant amount of global primary productivity. They are found in freshwater, marine and even some extremely severe environments. Among those environments, iron deficiency is one of the most common stress conditions in cyanobacterial habitats. To survive, cyanobacteria have evolved and developed several strategies to alleviate the damage caused by iron deficiency. Iron stress-inducible protein (IsiA) is a chlorophyll-binding membrane protein found in cyanobacteria grown in iron-deficient conditions. During the past decades, considerable effort has been put on understanding how IsiA functions to help cyanobacteria survive iron deficiency. It has been reported that IsiA ...


Secretory Iga Enhances Gut B Cells Priming And Systemic Igg Responses Towards Commensals, You Zhou Aug 2019

Secretory Iga Enhances Gut B Cells Priming And Systemic Igg Responses Towards Commensals, You Zhou

Arts & Sciences Electronic Theses and Dissertations

IgA is the primary antibody response at mucosal surfaces and is reported to inhibit adaptive immune responses against gut bacteria. Here, we utilize an in vitro system to expand and screen IgA memory B cells for their ability to recognize gut bacteria in the context of secretory IgA (sIgA) deficiency in polymeric Ig receptor (Pigr–/–) mice. Contrary to the prevailing hypothesis that IgA provides an immune exclusionary function, we found that mice lacking sIgA showed decreased anti-bacterial IgA specificities as assessed using flow cytometry. IgA B cell responses against certain taxa such as those of order Bacteriodales showed greater dependence ...


Macrophyte Distribution In Limestone Streams Of South Central Pennsylvania, Joshua Stone Aug 2019

Macrophyte Distribution In Limestone Streams Of South Central Pennsylvania, Joshua Stone

Honors Projects and Presentations: Undergraduate

Limestone streams are common in south-central Pennsylvania and arise from aquifers flowing through the abundant limestone (CaCO3) geography of the area. This action imbues the streams with several unique chemical characteristics, leading to a unique ecosystem that is occupied by very different flora and fauna from non-limestone streams in the same area. While calcium carbonate is not easily dissolved, travel through the limestone aquifer significantly changes the chemistry of the water. Limestone streams are characterized by an alkaline pH (7.0 - 8.0), ample plant nutrients, a stable and low temperature, and a relatively constant flow throughout the year ...


Parr Going The Distance: How Migratory Difficulty Influences Red Muscle Lipid Storage In Juvenile Oncorhynchus Mykiss, Emily Jean Morse Aug 2019

Parr Going The Distance: How Migratory Difficulty Influences Red Muscle Lipid Storage In Juvenile Oncorhynchus Mykiss, Emily Jean Morse

Dissertations and Theses

Adult salmonid populations embarking on difficult migrations have evolved to store more somatic energy prior to river entry. While it is known that lipids are the primary fuel for endurance swimming in fish, uncertainty still surrounds how these mechanisms are utilized by juvenile fish during seaward migration. A key phase in salmonid migration is the preparatory season of feeding and growth before swimming downstream. During this period, juvenile fish build somatic fuel stores through dietary uptake. Intestinal microbiota of steelhead trout (Oncorhynchus mykiss) vary drastically across their geographic range, with significant differences in the coastal and inland subspecies' microbiota lipid ...


Osmoregulation And Salinity Preference In Juvenile Sandbar Sharks (Carcharhinus Plumbeus) In Winyah Bay, Sc, Usa, Jessica Wingar Aug 2019

Osmoregulation And Salinity Preference In Juvenile Sandbar Sharks (Carcharhinus Plumbeus) In Winyah Bay, Sc, Usa, Jessica Wingar

Electronic Theses and Dissertations

Juvenile sandbar sharks (Carcharhinus plumbeus) have been caught in salinities ranging from 7 – 40. In Winyah Bay, a partially mixed estuary in Northeast SC, juvenile sandbar sharks tidally alternate between higher tides in middle bay and lower tides in lower bay. To assess salinity preference and duration in eight acoustically-tagged juvenile sandbar sharks in different salinities, acoustic receivers with salinity loggers were placed throughout Winyah Bay. Juvenile sandbar sharks were caught in salinities from 17.2 to 36.1 and acoustic detections were recorded from 11.5 to 24.7 by salinity loggers in middle bay. Smaller juvenile sandbar sharks ...


Differential Vulnerability To Window Collision Mortality Among Migratory Songbird Species, Olivia M. Colling Aug 2019

Differential Vulnerability To Window Collision Mortality Among Migratory Songbird Species, Olivia M. Colling

Electronic Thesis and Dissertation Repository

Millions of birds die annually in North America by colliding with windows. I investigated differential vulnerability to window collision among migratory songbird species using long-term citizen science datasets from two bird banding stations and the fatal light awareness program. I used negative binomial regressions to model species-specific catch ratios, a mixed-effects negative binomial regression to model trophic guild-specific catch ratios and mixed-effects logistic regressions to model the odds of catching different age classes. Species-specific vulnerability varied significantly. Blue-headed Vireos, Yellow-rumped Warblers and Ruby-crowned Kinglets were least vulnerable, while Ovenbirds, Common Yellowthroats, Fox Sparrows and Bay-breasted Warblers were most vulnerable. Foraging ...


Space Use And Nesting Ecology Of Common Ravens (Corvus Corax) In Central Washignton State, Brandon A. Rossi Aug 2019

Space Use And Nesting Ecology Of Common Ravens (Corvus Corax) In Central Washignton State, Brandon A. Rossi

Master of Biology Theses

The ecology and space use of Common ravens (Corvus corax; hereafter ravens) is not well understood in the shrub-steppe of central Washington State. Raven populations have increased by more than 254% since 1990 in Washington State (North American Breeding Bird Survey; www.mbr-pwrc.usgs.gov/bbs/). Ravens in central Washington are implicated as top predators of a small endemic population of greater sage-grouse (Centrocercus urophasianus). Researchers have related increased raven populations to anthropogenic subsidies such as landfills, agriculture, and livestock operations. Analyzing movement can help researchers understand the characteristics of habitat that are important and potentially drive population fluctuations. We ...


Flavobacterium Gliding Motility: From Protein Secretion To Cell Surface Adhesin Movements, Joseph Johnston Aug 2019

Flavobacterium Gliding Motility: From Protein Secretion To Cell Surface Adhesin Movements, Joseph Johnston

Theses and Dissertations

Flavobacterium johnsoniae exhibits rapid gliding motility over surfaces. At least twenty genes are involved in this process. Seven of these, gldK, gldL, gldM, gldN, sprA, sprE, and sprT encode proteins of the type IX protein secretion system (T9SS). The T9SS is required for surface localization of the motility adhesins SprB and RemA, and for secretion of the soluble chitinase ChiA. This thesis demonstrates that the gliding motility proteins GldA, GldB, GldD, GldF, GldH, GldI and GldJ are also essential for secretion. Cells with mutations in the genes encoding any of these seven proteins had normal levels of gldK mRNA but ...


The Functional Conservation Of Frazzled In Insects, Benjamin Wadsworth Aug 2019

The Functional Conservation Of Frazzled In Insects, Benjamin Wadsworth

Theses and Dissertations

Axons in the developing embryo receive and react to signals that direct their growth to reach target tissues at specified locations. The signal pathways that direct midline crossing of axons during embryonic development have been comprehensively examined in the past years using the Drosophila ventral nerve cord or the spinal cord as a model system. A number of these signaling mechanisms are conserved, however disparities have been found between species in general strategy or the molecular signals controlling the response of axons to guidance cues.

The Netrin-Frazzled pathway has been shown to aid in midline crossing of axons in the ...