Genetics and Genomics | Open Access Articles

Chemosensory Receptors In Berghia Stephanieae: Bioinformatics And Localization, Kelsi L. Watkins

Masters Theses

Chemosensation is achieved through the binding of chemical signals to chemoreceptor proteins embedded in the membranes of sensory neurons. The molecular identity of these receptors, as well as the downstream processing of chemosensory signals, has been well studied in arthropods and vertebrates. However, very little is known about molluscan chemosensation. The identity of chemoreceptor proteins in the nudibranch mollusc Berghia stephanieae are unknown. Data from other protostome and molluscan studies suggest Berghia may use ionotropic receptors for some forms of chemoreception. This study used a bioinformatics approach to identify potential chemosensory ionotropic receptors in the transcriptome of Berghia. A …

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The Receptor Basis Of Serotonergic Modulation In An Olfactory Network, Tyler Ryan Sizemore

Graduate Theses, Dissertations, and Problem Reports

Neuromodulation is a nearly ubiquitous process that endows the nervous system with the capacity to alter neural function at every level (synaptic, circuit, network, etc.) without necessarily adding new neurons. Through the actions of neuromodulators, the existing neural circuitry can be adaptively tuned to achieve flexible network output and similarly dynamic behavioral output. However, despite their near ubiquity in all sensory modalities, the mechanisms underlying neuromodulation of sensory processing remain poorly understood. In this dissertation, I address three main questions regarding the mechanisms of one modulator (serotonin) within one sensory modality (olfaction). I begin by establishing a "functional atlas" of …

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Employing High Probability Gene Choice Elements To Understand Singular Odorant Receptor Expression, Raena Mina

Dissertations, Theses, and Capstone Projects

The ability to detect odorous chemicals in the environment is the oldest of the senses necessary for survival, from escaping danger, finding mates, to locating food. It is said that humans can identify and discriminate up to a trillion different odor mixtures. For chemoreception to have such a high discriminatory power, would require a diverse population of cells dedicated for odor detection. These detector cells are the olfactory sensory neurons (OSNs), which express odorant receptors (ORs) that bind to chemical odors in the environment. In order to increase specificity and sensitivity, an essential property in olfaction is for each OSN …

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Probing The Limits Of Singular Gene Expression Through The Activity Of High Representation Odorant Receptor Transgenes, Eugene Lempert

Dissertations, Theses, and Capstone Projects

Singular gene expression is a common phenomenon in biology, making its appearance in immunoglobulin selection, protocadherin expression, X chromosome-inactivation, random monoallelic expression, and olfactory receptor choice. Singularity involves an activation and a feedback step. The mechanisms of singular gene choice have some capacity to integrate additional member genes while still maintaining singularity, but will activate an additional member if an earlier choice was incapable of triggering the feedback step. Odorant Receptor (OR) genes are substantially divergent from each other in terms of coding sequence, promoter structure, and genomic locus, all of which plays a role in how many Olfactory Sensory …

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Chemical Communication In Songbirds, Leanne A. Grieves

Electronic Thesis and Dissertation Repository

Avian chemical communication has been understudied due to the misconception that olfaction is unimportant or even lacking in birds. Early work focused on the olfactory foraging capabilities of seabirds because of their ecology (open ocean foraging) and large olfactory bulbs. In contrast, olfaction in passerine birds, comprising over half of all extant avian taxa, was long overlooked due to their relatively small olfactory bulbs. It is now well established that passerines can smell, and their olfactory acuity is comparable to that of macrosmatic mammals such as rats. Much of our theory on communication and mate choice has involved studying visual …

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Analysis Of The Chemotactic And Anti-Ovarian Response To Honeybee Queen Mandibular Pheromone (Qmp) And Its Constituent Components In Drosophila Melanogaster, Suhayr Solangi

Electronic Thesis and Dissertation Repository

Drosophila melanogaster can mimic qualities of honeybee altruism mediated by queen mandibular pheromone (QMP), a honeybee pheromone, which includes suppression of oogenesis and chemotactic attraction of males to sources of QMP. In this study, I assessed chemotaxis to the components of synthetic QMP (sQMP): the phenols; methyl-p-hydroxybenzoate (HOB) and 4-hydroxy-3-methoxyphenylethanol (HVA), and decenoic acids; 9-hydroxy-decenoic acid (9-HDA) and 9-oxo-decenoic acid (9-ODA). I found that the chemotactic response to these components is sexually dimorphic and they have complex interactions with one another. I conducted a screen to inhibit olfactory receptor neurons (ORN) using tetanus toxin (TeTx) and OrGAL4 drivers. Of the …

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Vertical‑Surface Navigation In The Neotropical Whip Spider Paraphrynus Laevifrons (Arachnida: Amblypygi), Patrick Casto, Daniel D. Wiegmann, Vincent J. Coppola, Daniele Nardi, Eileen A. Hebets, Verner P. Bingman

Eileen Hebets Publications

Studies on whip spider navigation have focused on their ability to locate goal locations in the horizontal plane (e.g., when moving along the ground). However, many species of tropical whip spiders reside and move along surfaces in the vertical plane (e.g., trees). Under controlled laboratory conditions, the current study investigated the ability of the tropical whip spider, Paraphrynus laevifrons, to return to a home shelter on a vertical surface in the presence of numerous, similar, and competing refuge sites, as well as the distribution of navigational errors in the vertical, horizontal, and diagonal plane. We also assessed the relative …

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Receptor-Mediated Maturation Of Olfactory Sensory Neurons: A Time Course Evaluation Of Neuronal Maturation In Neomorphic Mutants, Elizabeth Miller

Theses and Dissertations

How expression of odorant receptors affects the maturation of olfactory sensory neurons (OSNs) is not known. In a time course experiment, we show that wild type OSNs mature significantly more than those expressing Neomorphic mutant receptors. We conclude that functional receptors are critical to the differentiation and survival of OSNs.

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Importance Of The Antenniform Legs, But Not Vision, For Homing By The Neotropical Whip Spider Paraphrynus Laevifrons, Verner P. Bingman, Jacob M. Graving, Eileen Hebets, Daniel D. Wiegmann

Eileen Hebets Publications

Amblypygids, or whip spiders, are nocturnal, predatory arthropods that display a robust ability to navigate to their home refuge. Prior field observations and displacement studies in amblypygids demonstrated an ability to home from distances as far away as 10 m. In the current study, micro-transmitters were used to take morning position fixes of individual Paraphrynus laevifrons following an experimental displacement of 10 m from their home refuge. The intention was to assess the relative importance of vision compared with sensory input acquired from the antenniform legs for navigation as well as other aspects of their spatial behavior. Displaced individuals were …

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Odorant Receptor-Based Discovery Of Natural Repellents Of Human Lice, Julien Pelletier, Pingxi Xu, Kyong-Sup Yoon, John M. Clark, Walter S. Leal

SIUE Faculty Research, Scholarship, and Creative Activity

The body louse, Pediculus humanus humanus, is an obligate blood-feeding ectoparasite and an important insect vector that mediates the transmission of diseases to humans. The analysis of the body louse genome revealed a drastic reduction of the chemosensory gene repertoires when compared to other insects, suggesting specific olfactory adaptations to host specialization and permanent parasitic lifestyle. Here, we present for the first time functional evidence for the role of odorant receptors (ORs) in this insect, with the objective to gain insight into the chemical ecology of this vector. We identified seven putative full-length ORs, in addition to the odorant receptor …

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In Vivo Identification Of Eugenol-Responsive And Muscone-Responsive Mouse Odorant Receptors, Timothy S. Mcclintock, Kaylin Adipietro, William B. Titlow, Patrick Breheny, Andreas Walz, Peter Mombaerts, Hiroaki Matsunami

Physiology Faculty Publications

Our understanding of mammalian olfactory coding has been impeded by the paucity of information about the odorant receptors (ORs) that respond to a given odorant ligand in awake, freely behaving animals. Identifying the ORs that respond in vivo to a given odorant ligand from among the ∼1100 ORs in mice is intrinsically challenging but critical for our understanding of olfactory coding at the periphery. Here, we report an in vivo assay that is based on a novel gene-targeted mouse strain, S100a5-tauGFP, in which a fluorescent reporter selectively marks olfactory sensory neurons that have been activated recently in vivo. Because each …

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Multimodal Sensory Reliance In The Nocturnal Homing Of The Amblypygid Phrynus Pseudoparvulus (Class Arachnida, Order Amblypygi)?, Eileen A. Hebets, Alfonso Aceves-Aparicio, Samuel Aguilar-Argüello, Verner P. Bingman, Ignacio Escalante, Eben J. Gering, David R. Nelson, Jennifer Rivera, José Ángel Sánchez-Ruiz, Laura Segura-Hernández, Virginia Settepani, Daniel D. Wiegmann, Jay A. Stafstrom

Eileen Hebets Publications

Like many other nocturnal arthropods, the amblypygid Phrynus pseudoparvulus is capable of homing. The environment through which these predators navigate is a dense and heterogeneous tropical forest understory and the mechanism(s) underlying their putatively complex navigational abilities are presently unknown. This study explores the sensory inputs that might facilitate nocturnal navigation in the amblypygid P. pseudoparvulus. Specifically, we use sensory system manipulations in conjunction with field displacements to examine the potential involvement of multimodal—olfactory and visual—stimuli in P. pseudoparvulus’ homing behavior. In a first experiment, we deprived individuals of their olfactory capacity and displaced them to the opposite side of …

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Genetics and Genomics Commons^™

Full-Text Articles in Genetics and Genomics

Chemosensory Receptors In Berghia Stephanieae: Bioinformatics And Localization, Kelsi L. Watkins

Masters Theses

The Receptor Basis Of Serotonergic Modulation In An Olfactory Network, Tyler Ryan Sizemore

Graduate Theses, Dissertations, and Problem Reports

Employing High Probability Gene Choice Elements To Understand Singular Odorant Receptor Expression, Raena Mina

Dissertations, Theses, and Capstone Projects

Probing The Limits Of Singular Gene Expression Through The Activity Of High Representation Odorant Receptor Transgenes, Eugene Lempert

Dissertations, Theses, and Capstone Projects

Chemical Communication In Songbirds, Leanne A. Grieves

Electronic Thesis and Dissertation Repository

Analysis Of The Chemotactic And Anti-Ovarian Response To Honeybee Queen Mandibular Pheromone (Qmp) And Its Constituent Components In Drosophila Melanogaster, Suhayr Solangi

Electronic Thesis and Dissertation Repository

Vertical‑Surface Navigation In The Neotropical Whip Spider Paraphrynus Laevifrons (Arachnida: Amblypygi), Patrick Casto, Daniel D. Wiegmann, Vincent J. Coppola, Daniele Nardi, Eileen A. Hebets, Verner P. Bingman

Eileen Hebets Publications

Receptor-Mediated Maturation Of Olfactory Sensory Neurons: A Time Course Evaluation Of Neuronal Maturation In Neomorphic Mutants, Elizabeth Miller

Theses and Dissertations

Importance Of The Antenniform Legs, But Not Vision, For Homing By The Neotropical Whip Spider Paraphrynus Laevifrons, Verner P. Bingman, Jacob M. Graving, Eileen Hebets, Daniel D. Wiegmann

Eileen Hebets Publications

Odorant Receptor-Based Discovery Of Natural Repellents Of Human Lice, Julien Pelletier, Pingxi Xu, Kyong-Sup Yoon, John M. Clark, Walter S. Leal

SIUE Faculty Research, Scholarship, and Creative Activity

In Vivo Identification Of Eugenol-Responsive And Muscone-Responsive Mouse Odorant Receptors, Timothy S. Mcclintock, Kaylin Adipietro, William B. Titlow, Patrick Breheny, Andreas Walz, Peter Mombaerts, Hiroaki Matsunami

Physiology Faculty Publications

Eileen Hebets Publications