Life Sciences Commons^™

A New Species Of Boubou (Malaconotidae: Laniarius) From The Albertine Rift, Gary Voelker, Robert K. Outlaw, Sushma Reddy, Michael Tobler, John M. Bates, Shannon J. Hackett, Charles Kahindo, Ben D. Marks, Julian C. Kerbis Peterhans, Thomas P. Gnoske

Biology: Faculty Publications and Other Works

We describe Laniarius willardi, a new species of boubou shrike (Malaconotidae) from the Albertine Rift of Africa. The most conspicuous, distinguishing morphological feature of the species is a gray to blue-gray iris. This and external morphometric data indicate that L. willardi is diagnosable from other black or sooty boubous. Further, L. willardi is genetically diagnosable, and its closest relative is the Mountain Sooty Boubou (L. poensis camerunensis) from Cameroon. The Crimson-breasted Bush-shrike (L. atrococcineus) and the Lowland Sooty Boubou (L. leucorhynchus) are together the sister clade to L. willardi—L.p. camerunensis. Laniarius willardi and …

The Trpc2 Channel Forms Protein-Protein Interactions With Homer And Rtp In The Rat Vomeronasal Organ, Thomas G. Mast, Jessica H. Brann, Debra A. Fadool

Biology: Faculty Publications and Other Works

BACKGROUND: The signal transduction cascade operational in the vomeronasal organ (VNO) of the olfactory system detects odorants important for prey localization, mating, and social recognition. While the protein machinery transducing these external cues has been individually well characterized, little attention has been paid to the role of protein-protein interactions among these molecules. Development of an in vitro expression system for the transient receptor potential 2 channel (TRPC2), which establishes the first electrical signal in the pheromone transduction pathway, led to the discovery of two protein partners that couple with the channel in the native VNO. RESULTS: Homer family proteins were …

Regeneration Of New Neurons Is Preserved In Aged Vomeronasal Epithelia, Jessica H. Brann, Stuart Firestein

Biology: Faculty Publications and Other Works

During normal and diseased aging, it is thought the capacity for tissue regeneration and repair in neuronal tissues diminishes. In the peripheral olfactory system, stem cell reservoirs permit regeneration of olfactory and vomeronasal sensory neurons, a unique capacity among neurons. Following injury, a large number of new neurons can be regenerated in a young animal. However, it is unknown whether this capacity for renewal exists in aged proliferative populations. Here, we report that neuronal replacement-associated proliferation continues in the vomeronasal organ of aged (18-24 months) mice. In addition, the potential for the aged stem cell to yield a mature neuron …

Projected Loss Of A Salamander Diversity Hotspot As A Consequence Of Projected Global Climate Change, Joseph Milanovich, William E. Peterman, Nathan P. Nibbelink, John C. Maerz

Biology: Faculty Publications and Other Works

Significant shifts in climate are considered a threat to plants and animals with significant physiological limitations and limited dispersal abilities. The southern Appalachian Mountains are a global hotspot for plethodontid salamander diversity. Plethodontids are lungless ectotherms, so their ecology is strongly governed by temperature and precipitation. Many plethodontid species in southern Appalachia exist in high elevation habitats that may be at or near their thermal maxima, and may also have limited dispersal abilities across warmer valley bottoms.

Tak1 Is Required For The Survival Of Hematopoietic Cells And Hepatocytes In Mice, Minghui Tang, Xudong Wei, Yinshi Guo, Peter Breslin, Shubin Zhang, Shanshan Zhang, Wei Wei, Zhenbiao Xia, Manuel Diaz, Shizuo Akira, Jiwang Zhang

Biology: Faculty Publications and Other Works

Transforming growth factor beta-activated kinase 1 (TAK1), a member of the MAPKKK family, is a key mediator of proinflammatory and stress signals. Activation of TAK1 by proinflammatory cytokines and T and B cell receptors induces the nuclear localization of nuclear factor kappaB (NF-kappaB) and the activation of c-Jun N-terminal kinase (JNK)/AP1 and P38, which play important roles in mediating inflammation, immune responses, T and B cell activation, and epithelial cell survival. Here, we report that TAK1 is critical for the survival of both hematopoietic cells and hepatocytes. Deletion of TAK1 results in bone marrow (BM) and liver failure in mice …

Selective Gene Expression By Postnatal Electroporation During Olfactory Interneuron Nurogenesis, Alexander T. Chesler, Claire E. Le Pichon, Jessica H. Brann, Ricardo C. Araneda

Biology: Faculty Publications and Other Works

Neurogenesis persists in the olfactory system throughout life. The mechanisms of how new neurons are generated, how they integrate into circuits, and their role in coding remain mysteries. Here we report a technique that will greatly facilitate research into these questions. We found that electroporation can be used to robustly and selectively label progenitors in the Subventicular Zone. The approach was performed postnatally, without surgery, and with near 100% success rates. Labeling was found in all classes of interneurons in the olfactory bulb, persisted to adulthood and had no adverse effects. The broad utility of electroporation was demonstrated by encoding …

Diet Of Western Slimy Salamander, Plethodon Albagula (Caudata: Plethodontidae), From Two Mountain Ranges In Arkansas, Joseph Milanovich, Stanley E. Trauth, Tanja Mckay

Biology: Faculty Publications and Other Works

We identified stomach contents of 80 Plethodon albagula (Western Slimy Salamander) from two mountain ranges in Arkansas (Ozark and Ouachita) to examine if regional differences in diet occur. Museum specimens from 1985 to 2005 were used from locations throughout each mountain range. Although a wide variety of prey were found in stomachs, Hymenoptera: Formicidae and Coleoptera: Carabidae were found to be the most important food items in the diet of P. albagula. Ants and beetles constituted 85% abundance of their total diet (79.6% Ozark and 90.1% Ouachita) and 52.2% of their total biomass (42.6% Ozark and 64.1% Ouachita). Seventy-eight and …

Strategies For Odor Coding In The Piriform Cortex, Jessica H. Brann, Shari R. Saideman, Matthew T. Valley, Denise Wiedl

Biology: Faculty Publications and Other Works

No abstract provided.

Vomeronasal Sensory Neurons From Sternotherus Odoratus (Stinkpot/Musk Turtle) Respond To Chemosignals Via The Phospholipase C System, Jessica H. Brann, Debra A. Fadool

Biology: Faculty Publications and Other Works

The mammalian signal transduction apparatus utilized by vomeronasal sensory neurons (VSNs) in the vomeronasal organ (VNO) has been richly explored, while that of reptiles, and in particular, the stinkpot or musk turtle Sternotherus odoratus, is less understood. Given that the turtle's well-known reproductive and mating behaviors are governed by chemical communication, 247 patch-clamp recordings were made from male and female S. odoratus VSNs to study the chemosignal-activated properties as well as the second-messenger system underlying the receptor potential. Of the total neurons tested, 88 (35%) were responsive to at least one of five complex natural chemicals, some of which demonstrated …

Diaspora, A Large Family Of Ty3-Gypsy Retrotransposons In Glycine Max, Is An Envelope-Less Member Of An Endogenous Plant Retrovirus Lineage, Sho T. Yano, Bahman Panbehi, Arpita Das, Howard M. Laten

Biology: Faculty Publications and Other Works

Background

The chromosomes of higher plants are littered with retrotransposons that, in many cases, constitute as much as 80% of plant genomes. Long terminal repeat retrotransposons have been especially successful colonizers of the chromosomes of higher plants and examinations of their function, evolution, and dispersal are essential to understanding the evolution of eukaryotic genomes. In soybean, several families of retrotransposons have been identified, including at least two that, by virtue of the presence of an envelope-like gene, may constitute endogenous retroviruses. However, most elements are highly degenerate and are often sequestered in regions of the genome that sequencing projects initially …

Use Of 16s Rrna, 23s Rrna, And Gyrb Gene Sequence Analysis To Determine Phylogenetic Relationships Of Bacillus Cereus Group Microorganisms, Sergei G. Bavykin, Yuri P. Lysov, Vladimir Zakhariev, John J. Kelly, Joany Jackman, David A. Stahl, Alexey Cherni

Biology: Faculty Publications and Other Works

In order to determine if variations in rRNA sequence could be used for discrimination of the members of the Bacillus cereus group, we analyzed 183 16S rRNA and 74 23S rRNA sequences for all species in the B. cereus group. We also analyzed 30 gyrB sequences for B. cereus group strains with published 16S rRNA sequences. Our findings indicated that the three most common species of the B. cereus group, B. cereus, Bacillus thuringiensis, and Bacillus mycoides, were each heterogeneous in all three gene sequences, while all analyzed strains of Bacillus anthracis were found to be homogeneous. Based on analysis …

Optimization Of Single-Base-Pair Mismatch Discrimination In Oligonucleotide Microarrays, Hidetoshi Urakawa, Said El Fantroussi, H Smidt, James C. Smoot, Erik H. Tribou, John J. Kelly, Peter A. Noble, David A. Stahl

Biology: Faculty Publications and Other Works

The discrimination between perfect-match and single-base-pair-mismatched nucleic acid duplexes was investigated by using oligonucleotide DNA microarrays and nonequilibrium dissociation rates (melting profiles). DNA and RNA versions of two synthetic targets corresponding to the 16S rRNA sequences of Staphylococcus epidermidis (38 nucleotides) and Nitrosomonas eutropha (39 nucleotides) were hybridized to perfect-match probes (18-mer and 19-mer) and to a set of probes having all possible single-base-pair mismatches. The melting profiles of all probe-target duplexes were determined in parallel by using an imposed temperature step gradient. We derived an optimum wash temperature for each probe and target by using a simple formula to …

Direct Profiling Of Environmental Microbial Populations By Thermal Dissociation Analysis Of Native Rrnas Hybridized To Oligonucleotide Microarrays, Said El Fantroussi, Hidetoshi Urakawa, Anne E. Bernhard, John J. Kelly, Peter A. Noble, H Smidt, G M. Yershov, David A. Stahl

Biology: Faculty Publications and Other Works

Oligonucleotide microarrays were used to profile directly extracted rRNA from environmental microbial populations without PCR amplification. In our initial inspection of two distinct estuarine study sites, the hybridization patterns were reproducible and varied between estuarine sediments of differing salinities. The determination of a thermal dissociation curve (i.e., melting profile) for each probe-target duplex provided information on hybridization specificity, which is essential for confirming adequate discrimination between target and nontarget sequences.

Parallel Characterization Of Anaerobic Toluene-And Ethylbenzene-Degrading Microbial Consortia By Pcr-Denaturing Gradient Gel Electrophoresis, Rna-Dna Membrane Hybridization, And Dna Microarray Technology, Yoshikazu Koizumi, John J. Kelly, Tatsunori Nakagawa, Hidetoshi Urakawa, Said El Fantroussi, Saleh Al-Muzaini, Manubu Fukui, Yoshikuni Urushigawa, David A. Stahl

Biology: Faculty Publications and Other Works

A mesophilic toluene-degrading consortium (TDC) and an ethylbenzene-degrading consortium (EDC) were established under sulfate-reducing conditions. These consortia were first characterized by denaturing gradient gel electrophoresis (DGGE) fingerprinting of PCR-amplified 16S rRNA gene fragments, followed by sequencing. The sequences of the major bands (T-1 and E-2) belonging to TDC and EDC, respectively, were affiliated with the family Desulfobacteriaceae. Another major band from EDC (E-1) was related to an uncultured non-sulfate-reducing soil bacterium. Oligonucleotide probes specific for the 16S rRNAs of target organisms corresponding to T-1, E-1, and E-2 were designed, and hybridization conditions were optimized for two analytical formats, membrane and …

Single-Base-Pair Discrimination Of Terminal Mismatches By Using Oligonucleotide Microarrays And Neural Network Analyses, Hidetoshi Urakawa, Peter A. Noble, Said El Fantroussi, John J. Kelly, David A. Stahl

Biology: Faculty Publications and Other Works

The effects of single-base-pair near-terminal and terminal mismatches on the dissociation temperature (T(d)) and signal intensity of short DNA duplexes were determined by using oligonucleotide microarrays and neural network (NN) analyses. Two perfect-match probes and 29 probes having a single-base-pair mismatch at positions 1 to 5 from the 5' terminus of the probe were designed to target one of two short sequences representing 16S rRNA. Nonequilibrium dissociation rates (i.e., melting profiles) of all probe-target duplexes were determined simultaneously. Analysis of variance revealed that position of the mismatch, type of mismatch, and formamide concentration significantly affected the T(d) and signal intensity. …

Type-Specific Inositol 1,4,5-Trisphosphate Receptor Localization In The Vomeronasal Organ And Its Interaction With A Transient Receptor Potential Channel, Trpc2, Jessica H. Brann, John C. Dennis, Edward E. Morrison, Debra A. Fadool

Biology: Faculty Publications and Other Works

The vomeronasal organ (VNO) is the receptor portion of the accessory olfactory system and transduces chemical cues that identify social hierarchy, reproductive status, conspecifics and prey. Signal transduction in VNO neurons is apparently accomplished via an inositol 1,4,5-trisphosphate (IP3)-activated calcium conductance that includes a different set of G proteins than those identified in vertebrate olfactory sensory neurons. We used immunohistochemical (IHC) and SDS-PAGE/western analysis to localize three IP3 receptors (IP3R) in the rat VNO epithelium. Type-I IP3R expression was weak or absent. Antisera for type-II and -III IP3R recognized appropriate molecular weight proteins by SDS-PAGE, and labeled protein could be …

Patch-Clamp Analysis Of Voltage-Activated And Chemically Activated Currents In The Vomeronasal Organ Of Sternotherus Odoratus (Stinkpot/Musk Turtle), D. A. Fadool, M. Wachowiak, J. H. Brann

Biology: Faculty Publications and Other Works

The electrophysiological basis of chemical communication in the specialized olfactory division of the vomeronasal (VN) organ is poorly understood. In total, 198 patch-clamp recordings were made from 42 animals (Sternotherus odoratus, the stinkpot/musk turtle) to study the electrically and chemically activated properties of VN neurons. The introduction of tetramethylrhodamine-conjugated dextran into the VN orifice permitted good visualization of the vomeronasal neural epithelium prior to dissociating it into single neurons. Basic electrical properties of the neurons were measured (resting potential, -54.5 +/- 2.7 mV, N=11; input resistance, 6.7 +/- 1.4 G Omega, N=25; capacitance, 4.2 +/- 0.3 pF, N=22; means +/- …