Biology Commons^™

Glia Excitation In The Cns Modulates Intact Behaviors And Sensory-Cns-Motor Circuitry, Shelby Mccubbin, Douglas A. Harrison, Robin L. Cooper

Biology Faculty Publications

Glial cells play a role in many important processes, though the mechanisms through which they affect neighboring cells are not fully known. Insights may be gained by selectively activating glial cell populations in intact organisms utilizing the activatable channel proteins channel rhodopsin (ChR2XXL) and TRPA1. Here, the impacts of the glial-specific expression of these channels were examined in both larval and adult Drosophila. The Glia > ChR2XXL adults and larvae became immobile when exposed to blue light and TRPA1-expressed Drosophila upon heat exposure. The chloride pump expression in glia > eNpHR animals showed no observable differences in adults or larvae. In …

The Effect Of Optogenetically Activating Glia On Neuronal Function, Cecilia Pankau, Shelby Mccubbin, Robin L. Cooper

Biology Faculty Publications

Glia, or glial cells, are considered a vital component of the nervous system, serving as an electrical insulator and a protective barrier from the interstitial (extracellular) media. Certain glial cells (i.e., astrocytes, microglia, and oligodendrocytes) within the CNS have been shown to directly affect neural functions, but these properties are challenging to study due to the difficulty involved with selectively-activating specific glia. To overcome this hurdle, we selectively expressed light-sensitive ion channels (i.e., channel rhodopsin, ChR2-XXL) in glia of larvae and adult Drosophila melanogaster. Upon activation of ChR2, both adults and larvae showed a rapid contracture of body wall …

Effect Of Temperature On Heart Rate For Phaenicia Sericata And Drosophila Melanogaster With Altered Expression Of The Trpa1 Receptors, Nicole T. Marguerite, Jate Bernard, Douglas A. Harrison, David Harris, Robin L. Cooper

Biology Faculty Publications

The transient receptor potential (TrpA—ankyrin) receptor has been linked to pathological conditions in cardiac function in mammals. To better understand the function of the TrpA1 in regulation of the heart, a Drosophila melanogaster model was used to express TrpA1 in heart and body wall muscles. Heartbeat of in intact larvae as well as hearts in situ, devoid of hormonal and neural input, indicate that strong over-expression of TrpA1 in larvae at 30 or 37 °C stopped the heart from beating, but in a diastolic state. Cardiac function recovered upon cooling after short exposure to high temperature. Parental control larvae (UAS-TrpA1) …

The Effect Of Ph On Synaptic Transmission At The Neuromuscular Junction In Drosophila Melanogaster, Catherine Elizabeth Stanley

Theses and Dissertations--Biology

Synaptic transmission is the main avenue of neuronal communication and can be affected by a multitude of factors, both intracellularly and extracellularly. The effects of pH changes on synaptic transmission have been studied for many years across many different models. Intracellular acidification at the presynaptic terminal is known to occur with increased neuronal activity and can also occur in pathological conditions. The effects of these pH alterations are therefore an important area of study. Here, intracellular acidification using either propionic acid or the ammonium chloride pre-pulse technique was examined for the effects on both spontaneous and evoked synaptic transmission at …

The Effects Of A Bacterial Endotoxin On Behavior And Sensory-Cns-Motor Circuits In Drosophila Melanogaster, Oscar Istas, Abigail Greenhalgh, Robin L. Cooper

Biology Faculty Publications

The effect of bacterial sepsis on animal behavior and physiology is complex due to direct and indirect actions. The most common form of bacterial sepsis in humans is from gram-negative bacterial strains. The endotoxin (lipopolysaccharide, LPS) and/or associated peptidoglycans from the bacteria are the key agents to induce an immune response, which then produces a cascade of immunological consequences. However, there are direct actions of LPS and associated peptidoglycans on cells which are commonly overlooked. This study showed behavioral and neural changes in larval Drosophila fed commercially obtained LPS from Serratia marcescens. Locomotor behavior was not altered, but feeding …

The Effects Of A Ketone Body On Synaptic Transmission, Alexandra Elizabeth Stanback

Theses and Dissertations--Biology

The ketogenic diet is commonly used to control epilepsy, especially in cases when medications cannot. The diet typically consists of high fat, low carb, and adequate protein and produces a metabolite called acetoacetate. Seizure activity is characterized by glutamate excitotoxicity and therefore glutamate regulation is a point of research for control of these disorders. Acetoacetate is heavily implicated as the primary molecule responsible for decreasing glutamate in the synapse; it is believed that acetoacetate interferes with the transport of glutamate into the synaptic vesicles. The effects on synaptic transmission at glutamatergic synapses was studied in relation to the ketogenic diet …

Population Dynamics Based On Resource Availability & Founding Effects: Live & Computational Models, Samuel Potter, Rebecca M. Krall, Susan Mayo, Diane Johnson, Kimberly J. Zeidler-Watters, Robin L. Cooper

Biology Faculty Publications

With the looming global population crisis, it is more important now than ever that students understand what factors influence population dynamics. We present three learning modules with authentic, student-centered investigations that explore rates of population growth and the importance of resources. These interdisciplinary modules integrate biology, mathematics, and computer-literacy concepts aligned with the Next Generation Science Standards. The activities are appropriate for middle and high school science classes and for introductory college-level biology courses. The modules incorporate experimentation, data collection and analysis, drawing conclusions, and application of studied principles to explore factors affecting population dynamics in fruit flies. The variables …

Optogenetic Stimulation Of Drosophila Heart Rate At Different Temperatures And Ca2+ Concentrations, Yuechen Zhu, Henry Uradu, Zana R. Majeed, Robin L. Cooper

Biology Faculty Publications

Optogenetics is a revolutionary technique that enables noninvasive activation of electrically excitable cells. In mammals, heart rate has traditionally been modulated with pharmacological agents or direct stimulation of cardiac tissue with electrodes. However, implanted wires have been known to cause physical damage and damage from electrical currents. Here, we describe a proof of concept to optically drive cardiac function in a model organism, Drosophila melanogaster. We expressed the light sensitive channelrhodopsin protein ChR2.XXL in larval Drosophila hearts and examined light‐induced activation of cardiac tissue. After demonstrating optical stimulation of larval heart rate, the approach was tested at low temperature …

Lights And Larvae: Using Optogenetics To Teach Recombinant Dna And Neurobiology, John Titlow, Heidi Anderson, Robin L. Cooper

Biology Faculty Publications

Switching genes between organisms and controlling an animal’s brain using lasers may seem like science fiction, but with advancements in a technique called optogenetics, such experiments are now common in neuroscience research. Optogenetics combines recombinant DNA technology with a controlled light source to help researchers address biomedical questions in the life sciences. The technique has gained the most traction in neurobiology—the biology of the nervous system—where specific wavelengths of light are used to control or measure the activity of neurons in transgenic organisms (i.e., those with artificially inserted genes).

These optical recording and stimulation techniques are used in nervous system …

Dreadds In Drosophila: A Pharmacogenetic Approach For Controlling Behavior, Neuronal Signaling, And Physiology In The Fly, Jaime Becnel, Oralee Johnson, Zana R Majeed, Vi Tran, Bangning Yu, Bryan L. Roth, Robin L. Cooper, Edmund K. Kerut, Charles D. Nichols

Biology Faculty Publications

We have translated a powerful genetic tool, designer receptors exclusively activated by designer drugs (DREADDs), from mammalian systems to Drosophila melanogaster to selectively, rapidly, reversibly, and dose-dependently control behaviors and physiological processes in the fly. DREADDs are muscarinic acetylcholine G protein-coupled receptors evolved for loss of affinity to acetylcholine and for the ability to be fully activated by an otherwise biologically inert chemical, clozapine-N-oxide. We demonstrate its ability to control a variety of behaviors and processes in larvae and adults, including heart rate, sensory processing, diurnal behavior, learning and memory, and courtship. The advantages of this particular technology include the …

Cooperative And Antagonistic Contributions Of Two Heterochromatin Proteins To Transcriptional Regulation Of The Drosophila Sex Determination Decision, Hui Li, Janel Rodriguez, Youngdong Yoo, Momin Mohammed Shareef, Ramakrishna Badugu, Jamila I. Horabin, Rebecca Kellum

Biology Faculty Publications

Eukaryotic nuclei contain regions of differentially staining chromatin (heterochromatin), which remain condensed throughout the cell cycle and are largely transcriptionally silent. RNAi knockdown of the highly conserved heterochromatin protein HP1 in Drosophila was previously shown to preferentially reduce male viability. Here we report a similar phenotype for the telomeric partner of HP1, HOAP, and roles for both proteins in regulating the Drosophila sex determination pathway. Specifically, these proteins regulate the critical decision in this pathway, firing of the establishment promoter of the masterswitch gene, Sex-lethal (Sxl). Female-specific activation of this promoter, Sxl(Pe), is essential to females, as it provides SXL …

Analysis Of The Crmp Gene In Drosophila: Determining The Regulatory Role Of Crmp In Signaling And Behavior, Deanna Hardt Morris

University of Kentucky Doctoral Dissertations

The mammalian genome encodes five collapsin response mediator protein (CRMP) isoforms. Cell culture studies have shown that the CRMPs mediate growth cone dynamics and neuron polarity through associations with a variety of signal transduction components and cytoskeletal elements. CRMP is also a member of a protein family including the presumably ancestral dihydropyrimidinase (DHP) protein that catalyzes the second step in pyrimidine degradation. In Drosophila, CRMP and DHP proteins are produced by alternatively spliced transcripts of the CRMP gene. The alternative protein forms have a 91% sequence identity, but unique expression patterns. CRMP is found exclusively in neuronal tissues and …

The Influence Of Ca2+ Regulation In Synaptic Facilitation Of Motor Nerve Terminals In Crayfish And Drosophila As Well As In The Physiological Regulation Of Larval Drosophila Heart, Mohati Desai-Shah

University of Kentucky Doctoral Dissertations

Intracellular Ca²⁺ ions are highly regulated in animal cells for them to function normally. Since the tight regulation of [Ca²⁺]i is so ubiquitous among cells, it is not surprising that altered function in [Ca²⁺]i regulation is associated with a myriad of disease states in humans. This is particularly evident in pacing myocytes and nerve terminals related to synaptic transmission. A common thread through this dissertation is on the role of three regulators proteins that are common to many cell types. These are the plasmalemmal Na⁺/Ca²⁺ exchanger (NCX), the Ca²⁺-ATPase (PMCA) …

Monitoring Activity Of Drosophila Larvae: Impedance & Video Microscopy Measures, Ann Simone Cooper, Robin L. Cooper

Biology Faculty Publications

No abstract provided.

Monitoring Heart Rate In Drosophila Larvae By Various Approaches, Sameera Dasari, Robin L. Cooper

Biology Faculty Publications

No abstract provided.

Monitoring Carbon Dioxide Production By Drosophila Larvae, Robin L. Cooper, D. Nicholas Mcletchie

Biology Faculty Publications

No abstract provided.