Life Sciences Commons^™

Interactions Of Deet And Novel Repellents With Mosquito Odorant Receptors, Gariel G. Grant, Rachel R. Estrera, Narendra Pathak, C. Dennis Hall, Maia Tsikolia, Kenneth J. Linthicum, Ulrich R. Bernier, Adam C. Hall

Neuroscience: Faculty Publications

The carboxamide N,N-di-ethyl-meta-Toluamide (DEET) is the most effective and widely used insect repellent today. However, drawbacks concerning the efficacy and the safety of the repellent have led to efforts to design new classes of insect repellents. Through quantitative structure-Activity relationships, chemists have discovered two chemical groups of novel repellents: The acylpiperidines and the carboxamides, with the acylpiperidines generally more potent in biological assays. Although the exact mechanism of action of DEET and other repellents has not yet been thoroughly elucidated, previous research shows that the activity of insect odorant receptors are inhibited in the presence of repellents. The present electrophysiological …

Structural And Functional Determinants Of Rodent And Human Surfactant Protein A: A Synthesis Of Binding And Computational Data, Armen Nalian, Todd M. Umstead, Ching-Hui Yang, Patricia Silveyra, Neal J. Thomas, Joanna Floros, Francis X. Mccormack, Zissis C. Chroneos

Faculty Publications

Surfactant protein A (SP-A) provides surfactant stability, first line host defense, and lung homeostasis by binding surfactant phospholipids, pathogens, alveolar macrophages (AMs), and epithelial cells. Non-primates express one SP-A protein whereas humans express two: SP-A1 and SP-A2 with core intra- and inter-species differences in the collagen-like domain. Here, we used macrophages and solid phase binding assays to discern structural correlates of rat (r) and human (h) SP-A function. Binding assays using recombinant rSP-A expressed in insect cells showed that lack of proline hydroxylation, truncations of amino-terminal oligomerization domains, and site-directed serine (S) or alanine (A) mutagenesis of cysteine 6 (C6S), …

Utilizing Phluorin-Tagged Receptors To Monitor Subcellular Localization And Trafficking, Ashley M. Fox-Loe, Brandon J. Henderson, Christopher I. Richards

Chemistry Faculty Publications

Understanding membrane protein trafficking, assembly, and expression requires an approach that differentiates between those residing in intracellular organelles and those localized on the plasma membrane. Traditional fluorescence-based measurements lack the capability to distinguish membrane proteins residing in different organelles. Cutting edge methodologies transcend traditional methods by coupling pH-sensitive fluorophores with total internal reflection fluorescence microscopy (TIRFM). TIRF illumination excites the sample up to approximately 150 nm from the glass-sample interface, thus decreasing background, increasing the signal to noise ratio, and enhancing resolution. The excitation volume in TIRFM encompasses the plasma membrane and nearby organelles such as the peripheral ER. Superecliptic …

Tissue-Specific Thyroid Hormone Regulation Of Gene Transcripts Encoding Iodothyronine Deiodinases And Thyroid Hormone Receptors In Striped Parrotfish (Scarus Iseri), Kaitlin M. Johnson, Sean C. Lema

Biological Sciences

In fish as in other vertebrates, the diverse functions of thyroid hormones are mediated at the peripheral tissue level through iodothyronine deiodinase (dio) enzymes and thyroid hormone receptor (tr) proteins. In this study, we examined thyroid hormone regulation of mRNAs encoding the three deiodinases dio1, dio2 and dio3 – as well as three thyroid hormone receptors trαA, trαB and trβ – in initial phase striped parrotfish (Scarus iseri). Parrotfish were treated with dissolved phase T₃ (20 nM) or methimazole (3 mM) for 3 days. Treatment with exogenous T₃ elevated circulating T₃, while the …

Diurnal Rhythms Of Behavior And Brain Mrna Expression For Arginine Vasotocin, Isotocin, And Their Receptors In Wild Amargosa Pupfish (Cyprinodon Nevadensis Amargosae), Sean C. Lema, Lauren J. Wagstaff, Nina M. Gardner

Biological Sciences

Amargosa pupfish (Cyprinodon nevadensis amargosae) occupy remote desert habitats that vary widely in environmental conditions from day to night. In this study, die! patterns of behavior were documented for pupfish in their natural habitat, and examined relative to changes in the abundance of mRNAs encoding prepro-arginine vasotocin (pro-VT), prepro-isotocin (pro-IT), three distinct vasotocin receptors (V1a1, V1a2, and V2), and an isotocin receptor (ITR) in the brain. The behavior of wild pupfish varied diurnally, with frequent aggression from 12:00 to 15:00 h and courtship and spawning most common between 15:00 and 19:00h. Transcript abundance for pro-VT in the brain …

Identification Of Multiple Vasotocin Receptor Cdnas In Teleost Fish: Sequences, Phylogenetic Analysis, Sites Of Expression, And Regulation In The Hypothalamus And Gill In Response To Hyperosmotic Challenge, Sean C. Lema

Biological Sciences

Vasopressin and its homolog vasotocin regulate hydromineral balance, stress responses, and social behaviors in vertebrates. In mammals, the functions of vasopressin are mediated via three classes of membrane-bound receptors: V1a-type, V1b-type and V2-type. To date, however, only a single class of vasotocin receptor has been identified in teleost fish. Here, cDNAs encoding three putative vasotocin receptors – two distinct V1a-type receptor paralogs (V1a1 and V1a2) and a previously undescribed V2- type receptor (V2) – and a single isotocin receptor were isolated and sequenced from the Amargosa pupfish (Cyprinodon nevadensis amargosae). RT-PCR revealed that mRNAs …

Characterizing The Polycation Receptor Of Paramecium, Eric D. Robinette, Heather G. Kuruvilla

Science and Mathematics Faculty Presentations

Unicellular eukaryotes are complex systems, performing all the tasks needed for survival within the context of a single cell. Protozoans, such as Tetrahymena and Paramecium, use chemosensory systems to detect food and to avoid predation.

Both Tetrahymena and Paramecium have been used as models for studying chemorepellents. Lysozyme, ATP, and GTP have been found to have chemorepellent activity in both ciliates. In Tetrahymena, several PACAP isoforms have been shown to bind to the same receptor as lysozyme, indicating that this receptor may be a more general “polycation receptor” (Keedy et al., 2003). The polycation receptor in Tetrahymena appears to be …

Two Drosophila Suppressors Of Cytokine Signaling (Socs) Differentially Regulate Jak And Egfr Pathway Activities, Jason S. Rawlings, Gabriela Rennebeck, Susan M.W. Harrison, Rongwen Xi, Douglas A. Harrison

Biology Faculty Publications

BACKGROUND: The Janus kinase (JAK) cascade is an essential and well-conserved pathway required to transduce signals for a variety of ligands in both vertebrates and invertebrates. While activation of the pathway is essential to many processes, mutations from mammals and Drosophila demonstrate that regulation is also critical. The SOCS (Suppressor Of Cytokine Signaling) proteins in mammals are regulators of the JAK pathway that participate in a negative feedback loop, as they are transcriptionally activated by JAK signaling. Examination of one Drosophila SOCS homologue, Socs36E, demonstrated that its expression is responsive to JAK pathway activity and it is capable of downregulating …