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2008

Biology Faculty Publications

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A Cell Biology Laboratory Exercise To Study Sub-Cellular Organelles In Drosophila, Meghana Tare, Amit Singh Dec 2008

A Cell Biology Laboratory Exercise To Study Sub-Cellular Organelles In Drosophila, Meghana Tare, Amit Singh

Biology Faculty Publications

The fast-changing scenario of undergraduate education puts emphasis on introducing students to hands-on techniques as part of their laboratory courses. In order to cater to large numbers of students and the time constraints involved with undergraduate level laboratory courses, there is a need for development of experiments that are cost effective and can be completed in a defined time frame. We have devised a laboratory exercise for teaching cell biology using the Drosophila melanogaster model. Drosophila can be reared in a short period of time in a cost effective manner. We used Drosophila tissue to study the sub-cellular organization of …


Recombination-Based In Vivo Expression Technology Identifies Helicobacter Pylori Genes Important For Host Colonization, Andrea Castillo, Andrew J. Woodruff, Lynn E. Connolly, William E. Sause, Karen M. Ottemann Dec 2008

Recombination-Based In Vivo Expression Technology Identifies Helicobacter Pylori Genes Important For Host Colonization, Andrea Castillo, Andrew J. Woodruff, Lynn E. Connolly, William E. Sause, Karen M. Ottemann

Biology Faculty Publications

Here we undertook to identify colonization and gastric disease-promoting factors of the human gastric pathogen Helicobacter pylori as genes that were induced in response to the stomach environment. Using recombination-based in vivo expression technology (RIVET), we identified six promoters induced in the host compared to laboratory conditions. Three of these promoters, designated Pivi10, Pivi66, and Pivi77, regulate genes that H. pylori may use to interact with other microbes or the host. Pivi10 likely regulates the mobA, mobB, and mobD genes, which have potential roles in horizontal gene transfer through plasmid mobilization. Pivi66 occurs in the cytotoxin-associated gene pathogenicity island, a …


Environmental Issues In Russia, Laura A. Henry, Vladimir Douhovnikoff Dec 2008

Environmental Issues In Russia, Laura A. Henry, Vladimir Douhovnikoff

Biology Faculty Publications

This review examines the literature available on the state of the environment and environmental protection in the Russian Federation. As the largest country on Earth, rich in natural resources and biodiversity, Russia's problems and policies have global consequences. Environmental quality and management are influenced by the legacy of Soviet economic planning and authoritarian governance, as well as by Russia's post-Soviet economic recession and current strategies of economic development. Russia achieved a reduction in some pollutants owing to the collapse of industrial production in the 1990s, but many environmental indicators suggest growing degradation. Russia has signed on to a number of …


Successful Implementation Of Inquiry-Based Physiology Laboratories In Undergraduate Major And Nonmajor Courses, Giovanni Casotti, Loretta Rieser-Danner, Maureen T. Knabb Dec 2008

Successful Implementation Of Inquiry-Based Physiology Laboratories In Undergraduate Major And Nonmajor Courses, Giovanni Casotti, Loretta Rieser-Danner, Maureen T. Knabb

Biology Faculty Publications

No abstract provided.


Spots Of Adult Male Red-Spotted Newts Are Redder And Brighter Than In Females: Evidence For A Role In Mate Selection?, Andrew K. Davis, Kristine L. Grayson Nov 2008

Spots Of Adult Male Red-Spotted Newts Are Redder And Brighter Than In Females: Evidence For A Role In Mate Selection?, Andrew K. Davis, Kristine L. Grayson

Biology Faculty Publications

As aquatic adults, eastern red-spotted newts (Notophthalmus v. viridescens) are generally green with two rows of dorsal spots, which vary in number between individuals and range in colour from orange to red. The function of these spots is unknown, but it is possible that they serve as sexual ornamentations and we examined this hypothesis by testing for sexual dimorphism in spot characteristics. We used an image analysis approach that has been used previously with this and other amphibian species to compare the number, size and colour – redness (hue score) and brightness – of spots in 100 male …


A Simple Polymerase Chain Reaction-Based Method For The Construction Of Recombinase-Mediated Cassette Exchange Donor Vectors, Jack R. Bateman, C. Ting Wu Nov 2008

A Simple Polymerase Chain Reaction-Based Method For The Construction Of Recombinase-Mediated Cassette Exchange Donor Vectors, Jack R. Bateman, C. Ting Wu

Biology Faculty Publications

Here we describe a simple method for generating donor vectors suitable for targeted transgenesis via recombinase-mediated cassette exchange (RMCE) using the ΦC31 integrase. This PCR-based strategy employs small attB "tails" on the primers used to amplify a sequence of interest, permitting the rapid creation of transgenes for in vivo analysis. Copyright © 2008 by the Genetics Society of America.


A Genomewide Survey Argues That Every Zygotic Gene Product Is Dispensable For The Initiation Of Somatic Homolog Pairing In Drosophila, Jack R. Bateman, C. Ting Wu Nov 2008

A Genomewide Survey Argues That Every Zygotic Gene Product Is Dispensable For The Initiation Of Somatic Homolog Pairing In Drosophila, Jack R. Bateman, C. Ting Wu

Biology Faculty Publications

Studies from diverse organisms show that distinct interchromosomal interactions are associated with many developmental events. Despite recent advances in uncovering such phenomena, our understanding of how interchromosomal interactions are initiated and regulated is incomplete. During the maternal-to-zygotic transition (MZT) of Drosophila embryogenesis, stable interchromosomal contacts form between maternal and paternal homologous chromosomes, a phenomenon known as somatic homolog pairing. To better understand the events that initiate pairing, we performed a genomewide assessment of the zygotic contribution to this process. Specifically, we took advantage of the segregational properties of compound chromosomes to generate embryos lacking entire chromosome arms and, thus, all …


Transcriptional Response Of Mexican Axolotls To Ambystoma Tigrinum Virus (Atv) Infection, Jennifer D. Cotter, Andrew Storfer, Robert B. Page, Christopher K. Beachy, S. Randal Voss Oct 2008

Transcriptional Response Of Mexican Axolotls To Ambystoma Tigrinum Virus (Atv) Infection, Jennifer D. Cotter, Andrew Storfer, Robert B. Page, Christopher K. Beachy, S. Randal Voss

Biology Faculty Publications

BACKGROUND: Very little is known about the immunological responses of amphibians to pathogens that are causing global population declines. We used a custom microarray gene chip to characterize gene expression responses of axolotls (Ambystoma mexicanum) to an emerging viral pathogen, Ambystoma tigrinum virus (ATV).

RESULT: At 0, 24, 72, and 144 hours post-infection, spleen and lung samples were removed for estimation of host mRNA abundance and viral load. A total of 158 up-regulated and 105 down-regulated genes were identified across all time points using statistical and fold level criteria. The presumptive functions of these genes suggest a robust innate immune …


Transcriptional Response Of Mexican Axolotls To Ambystoma Tigrinum Virus (Atv) Infection, Jennifer D. Cotter, Andrew Storfer, Robert B. Page, Christopher K. Beachy, S. Randal Voss Oct 2008

Transcriptional Response Of Mexican Axolotls To Ambystoma Tigrinum Virus (Atv) Infection, Jennifer D. Cotter, Andrew Storfer, Robert B. Page, Christopher K. Beachy, S. Randal Voss

Biology Faculty Publications

Background

Very little is known about the immunological responses of amphibians to pathogens that are causing global population declines. We used a custom microarray gene chip to characterize gene expression responses of axolotls (Ambystoma mexicanum) to an emerging viral pathogen, Ambystoma tigrinum virus (ATV).

Result

At 0, 24, 72, and 144 hours post-infection, spleen and lung samples were removed for estimation of host mRNA abundance and viral load. A total of 158 up-regulated and 105 down-regulated genes were identified across all time points using statistical and fold level criteria. The presumptive functions of these genes suggest a robust …


Evaluation Of An Oral Vaccination Program To Control Raccoon Rabies In A Suburbanized Landscape, Jason R. Boulanger, Laura L. Bigler, Paul D. Curtis, Donald H. Lein, Arthur J. Lembo Jr. Oct 2008

Evaluation Of An Oral Vaccination Program To Control Raccoon Rabies In A Suburbanized Landscape, Jason R. Boulanger, Laura L. Bigler, Paul D. Curtis, Donald H. Lein, Arthur J. Lembo Jr.

Biology Faculty Publications

We evaluated the efficacy of an oral rabies vaccination (ORV) program conducted in Erie County, New York, from July through September, 2002–2005. Ingress of the raccoon (Procyon lotor) rabies variant first occurred along the southern border of Erie County, New York, during 1992 and began to spread northward at a velocity of 31 km/year. Fixed-wing aircraft dropped ORV baits in rural landscapes; helicopters, hand baiting, and bait stations distributed baits in suburban landscapes (x̄ bait densities ranged 59–118 baits/km2). Our study objectives were to quantify rabies case densities, evaluate efficacy of intervention efforts, and determine biological, …


Distinct Contributions Of Model Masp1 And Masp2 Like Peptides To The Mechanical Properties Of Synthetic Major Ampullate Silk Fibers As Revealed In Silico, Amanda E. Brooks, Shane R. Nelson, Justin A. Jones, Courtney Koenig, Michael Hinman, Michael Hinman, Shane Stricker, Randolph V. Lewis Aug 2008

Distinct Contributions Of Model Masp1 And Masp2 Like Peptides To The Mechanical Properties Of Synthetic Major Ampullate Silk Fibers As Revealed In Silico, Amanda E. Brooks, Shane R. Nelson, Justin A. Jones, Courtney Koenig, Michael Hinman, Michael Hinman, Shane Stricker, Randolph V. Lewis

Biology Faculty Publications

All characterized major ampullate silks from orb-web weaving spiders are composites of primarily two different proteins: MaSp1 and MaSp2. The conserved association of MaSp1 and MaSp2 in these spider species, the highly conserved amino acid motifs, and variable ratios of MaSp1 to MaSp2 demonstrate the importance of both MaSp1 and MaSp2 to the strength and elasticity of the fiber. Computer simulated mechanical tests predicted differing roles for MaSp1 and MaSp2 in the mechanical properties of the fibers. Recombinant MaSp1 and MaSp2 proteins were blended and spun into fibers mimicking the computer-simulated conditions. Mechanical testing verified the differing roles of MaSp1 …


Molecular Basis Of The Copulatory Plug Polymorphism In Caenorhabditis Elegans, Michael F. Palopoli, Matthew V. Rockman, Aye Tinmaung, Camden Ramsay, Stephen Curwen, Andrea Aduna, Jason Laurita, Leonid Kruglyak Aug 2008

Molecular Basis Of The Copulatory Plug Polymorphism In Caenorhabditis Elegans, Michael F. Palopoli, Matthew V. Rockman, Aye Tinmaung, Camden Ramsay, Stephen Curwen, Andrea Aduna, Jason Laurita, Leonid Kruglyak

Biology Faculty Publications

Heritable variation is the raw material for evolutionary change, and understanding its genetic basis is one of the central problems in modern biology. We investigated the genetic basis of a classic phenotypic dimorphism in the nematode Caenorhabditis elegans. Males from many natural isolates deposit a copulatory plug after mating, whereas males from other natural isolates-including the standard wild-type strain (N2 Bristol) that is used in most research laboratories-do not deposit plugs. The copulatory plug is a gelatinous mass that covers the hermaphrodite vulva, and its deposition decreases the mating success of subsequent males. We show that the plugging polymorphism results …


Response Properties Of The Auditory Telencephalon In Songbirds Change With Recent Experience And Season, Thomas A. Terleph, Kai Lu, David S. Vicario Aug 2008

Response Properties Of The Auditory Telencephalon In Songbirds Change With Recent Experience And Season, Thomas A. Terleph, Kai Lu, David S. Vicario

Biology Faculty Publications

The caudomedial nidopallium (NCM) is a telencephalic auditory area that is selectively activated by conspecific vocalizations in zebra finches and canaries. We recently demonstrated that temporal and spectral dynamics of auditory tuning in NCM differ between these species [1]. In order to determine whether these differences reflect recent experience, we exposed separate groups of each species and sex to different housing conditions. Adult birds were housed either in an aviary with conspecifics (NORM), with heterospecifics (canary subjects in a zebra finch aviary, and vice versa: (CROSS)), or in isolation (ISO) for 9 days prior to testing. We then recorded extracellular …


Pheromones Enhance Somatosensory Processing In Newt Brains Through A Vasotocin-Dependent Mechanism, R. R. Thompson, P. S. Dickinson, J. D. Rose, K. A. Dakin, G. M. Civiello, A. Segerdahl, R. Bartlett Jul 2008

Pheromones Enhance Somatosensory Processing In Newt Brains Through A Vasotocin-Dependent Mechanism, R. R. Thompson, P. S. Dickinson, J. D. Rose, K. A. Dakin, G. M. Civiello, A. Segerdahl, R. Bartlett

Biology Faculty Publications

We tested whether the sex pheromones that stimulate courtship clasping in male roughskin newts do so, at least in part, by amplifying the somatosensory signals that directly trigger the motor pattern associated with clasping and, if so, whether that amplification is dependent on endogenous vasotocin (VT). Female olfactory stimuli increased the number of action potentials recorded in the medulla of males in response to tactile stimulation of the cloaca, which triggers the clasp motor reflex, as well as to tactile stimulation of the snout and hindlimb. That enhancement was blocked by exposing the medulla to a V1a receptor antagonist before …


Spiderworts: Not Just Another Pretty Face For Science, W. John Hayden Jul 2008

Spiderworts: Not Just Another Pretty Face For Science, W. John Hayden

Biology Faculty Publications

Species of Tradescantia, or spiderworts, are handsome plants. Several wild species, including the VNPS wildflower of the Year for 2008 (T. virginiana), can be found in eastern North America and additional species grace gardens, and hothouse conservatories. Spiderworts are not, however, just a bunch of pretty faces. Spiderworts have a long history of service to science, both in terms of teaching and pure research.


Estimating Gene Signals From Noisy Microarray Images, Pinaki Sarder, Arye Nehorai, Paul H. Davis, Samuel L. Stanley Jr. Jun 2008

Estimating Gene Signals From Noisy Microarray Images, Pinaki Sarder, Arye Nehorai, Paul H. Davis, Samuel L. Stanley Jr.

Biology Faculty Publications

In oligonucleotide microarray experiments, noise is a challenging problem, as biologists now are studying their organisms not in isolation but in the context of a natural environment. In low photomultiplier tube (PMT) voltage images, weak gene signals and their interactions with the background fluorescence noise are most problematic. In addition, nonspecific sequences bind to array spots intermittently causing inaccurate measurements. Conventional techniques cannot precisely separate the foreground and the background signals. In this paper, we propose analytically based estimation technique. We assume a priori spot-shape information using a circular outer periphery with an elliptical center hole. We assume Gaussian statistics …


An Improved String Composition Method For Sequence Comparison, Guoquing Lu, Shunpu Zhang, Xiang Fang May 2008

An Improved String Composition Method For Sequence Comparison, Guoquing Lu, Shunpu Zhang, Xiang Fang

Biology Faculty Publications

Background: Historically, two categories of computational algorithms (alignment-based and alignment-free) have been applied to sequence comparison–one of the most fundamental issues in bioinformatics. Multiple sequence alignment, although dominantly used by biologists, possesses both fundamental as well as computational limitations. Consequently, alignment-free methods have been explored as important alternatives in estimating sequence similarity. Of the alignment-free methods, the string composition vector (CV) methods, which use the frequencies of nucleotide or amino acid strings to represent sequence information, show promising results in genome sequence comparison of prokaryotes. The existing CV-based methods, however, suffer certain statistical problems, thereby underestimating the amount of evolutionary …


A Bbp-Mud2p Heterodimer Mediates Branchpoint Recognition And Influences Splicing Substrate Abundance In Budding Yeast, Qiang Wang, Li Zhang, Bert C. Lynn, Brian C. Rymond May 2008

A Bbp-Mud2p Heterodimer Mediates Branchpoint Recognition And Influences Splicing Substrate Abundance In Budding Yeast, Qiang Wang, Li Zhang, Bert C. Lynn, Brian C. Rymond

Biology Faculty Publications

The 3′ end of mammalian introns is marked by the branchpoint binding protein, SF1, and the U2AF65-U2AF35 heterodimer bound at an adjacent sequence. Baker's yeast has equivalent proteins, branchpoint binding protein (BBP) (SF1) and Mud2p (U2AF65), but lacks an obvious U2AF35 homolog, leaving open the question of whether another protein substitutes during spliceosome assembly. Gel filtration, affinity selection and mass spectrometry were used to show that rather than a U2AF65/U2AF35-like heterodimer, Mud2p forms a complex with BBP without a third (U2AF35-like) factor. Using mutants of MUD2 and BBP, we show that the BBP–Mud2p complex bridges partner-specific Prp39p, Mer1p, Clf1p …


The Pyloric Neural Circuit Of The Herbivorous Crab Pugettia Producta Shows Limited Sensitivity To Several Neuromodulators That Elicit Robust Effects In More Opportunistically Feeding Decapods, Patsy S. Dickinson, Elizabeth A. Stemmler, Andrew E. Christie May 2008

The Pyloric Neural Circuit Of The Herbivorous Crab Pugettia Producta Shows Limited Sensitivity To Several Neuromodulators That Elicit Robust Effects In More Opportunistically Feeding Decapods, Patsy S. Dickinson, Elizabeth A. Stemmler, Andrew E. Christie

Biology Faculty Publications

Modulation of neural circuits in the crustacean stomatogastric nervous system (STNS) allows flexibility in the movements of the foregut musculature. The extensive repertoire of such resulting motor patterns in dietary generalists is hypothesized to permit these animals to process varied foods. The foregut and STNS of Pugettia producta are similar to those of other decapods, but its diet is more uniform, consisting primarily of kelp. We investigated the distribution of highly conserved neuromodulators in the stomatogastric ganglion (STG) and neuroendocrine organs of Pugettia, and documented their effects on its pyloric rhythm. Using immunohistochemistry, we found that the distributions of Cancer …


Assessment Of A Non-Invasive High-Throughput Classifier For Behaviours Associated With Sleep And Wake In Mice, Kevin D. Donohue, Dharshan C. Medonza, Eli R. Crane, Bruce F. O'Hara Apr 2008

Assessment Of A Non-Invasive High-Throughput Classifier For Behaviours Associated With Sleep And Wake In Mice, Kevin D. Donohue, Dharshan C. Medonza, Eli R. Crane, Bruce F. O'Hara

Biology Faculty Publications

This work presents a non-invasive high-throughput system for automatically detecting characteristic behaviours in mice over extended periods of time, useful for phenotyping experiments. The system classifies time intervals on the order of 2 to 4 seconds as corresponding to motions consistent with either active wake or inactivity associated with sleep. A single Polyvinylidine Difluoride (PVDF) sensor on the cage floor generates signals from motion resulting in pressure. This paper develops a linear classifier based on robust features extracted from normalized power spectra and autocorrelation functions, as well as novel features from the collapsed average (autocorrelation of complex spectrum), which characterize …


A New Reproductive Mode In The Genus Melanzophryniscus Gallardo, 1961 (Anura: Bufonidae) With Description Of A New Species From The State Of Paraná, Brazil, José A. Langone, Magno V. Segallo, Marcos Bornschein, Rafael O. De Sá Apr 2008

A New Reproductive Mode In The Genus Melanzophryniscus Gallardo, 1961 (Anura: Bufonidae) With Description Of A New Species From The State Of Paraná, Brazil, José A. Langone, Magno V. Segallo, Marcos Bornschein, Rafael O. De Sá

Biology Faculty Publications

A new species of bufonid toad of the genus Melanophryniscus is described from a mountaintop that is part of the Serra do Mar in the northeastern State of Paraná, Brazil. Melanophryniscus alipioi sp. nov. is distinguished from other known species by its uniformly dark brown dorsal color and a unique breeding site. The new species reproduces in bromeliads, a reproductive mode previously unknown for this genus. This species might be susceptible to current habitat lost.


The Horseshoe Crab Conundrum: Can We Harvest And Conserve?, Jennifer Mattei, Mark Beekey Apr 2008

The Horseshoe Crab Conundrum: Can We Harvest And Conserve?, Jennifer Mattei, Mark Beekey

Biology Faculty Publications

Horeshoe crabs "Limulus polyphemus" are remarkable ‘living fossils’ which have unique blood cells (amebocytes) that are used to test human vaccines for bacterial contamination. In the 1950’s, scientists at the Marine Biological Laboratory in Woods Hole, Massachusetts, not only discovered amebocytes but also found that they had special properties. If the amebocytes came into contact with bacteria, they would instantly coagulate around the bacteria and attack it. The Woods Hole scientists took this unique property of horseshoe crabs and developed a test for bacterial contamination using a horseshoe crab blood derivative called Limulus Amebocyte Lysate (LAL).

This article describes discusses …


Probing The Mechanism Of Recognition Of Ssdna By The Cdc13-Dbd, Aimee M. Eldridge, Deborah S. Wuttke Mar 2008

Probing The Mechanism Of Recognition Of Ssdna By The Cdc13-Dbd, Aimee M. Eldridge, Deborah S. Wuttke

Biology Faculty Publications

The Saccharomyces cerevisiae protein Cdc13 tightly and specifically binds the conserved G-rich single-stranded overhang at telomeres and plays an essential role in telomere end-protection and length regulation. The 200 residue DNA-binding domain of Cdc13 (Cdc13-DBD) binds an 11mer single-stranded representative of the yeast telomeric sequence [Tel11, d(GTGTGGGTGTG)] with a 3 pM affinity and specificity for three bases (underlined) at the 5′ end. The structure of the Cdc13-DBD bound to Tel11 revealed a large, predominantly aromatic protein interface with several unusual features. The DNA adopts an irregular, extended structure, and the binding interface includes a long (∼30 amino acids) structured loop …


A Songbird Forebrain Area Potentially Involved In Auditory Discrimination And Memory Formation, Raphael Pinaud, Thomas A. Terleph Mar 2008

A Songbird Forebrain Area Potentially Involved In Auditory Discrimination And Memory Formation, Raphael Pinaud, Thomas A. Terleph

Biology Faculty Publications

Songbirds rely on auditory processing of natural communication signals for a number of social behaviors, including mate selection, individual recognition and the rare behavior of vocal learning - the ability to learn vocalizations through imitation of an adult model, rather than by instinct. Like mammals, songbirds possess a set of interconnected ascending and descending auditory brain pathways that process acoustic information and that are presumably involved in the perceptual processing of vocal communication signals. Most auditory areas studied to date are located in the caudomedial forebrain of the songbird and include the thalamo-recipient field L (subfields L1, L2 and L3), …


Effect Of Thyroid Hormone Concentration On The Transcriptional Response Underlying Induced Metamorphosis In The Mexican Axolotl (Ambystoma), Robert B. Page, Stephen R. Voss, Amy K. Samuels, Jeramiah J. Smith, Srikrishna Putta, Christopher K. Beachy Feb 2008

Effect Of Thyroid Hormone Concentration On The Transcriptional Response Underlying Induced Metamorphosis In The Mexican Axolotl (Ambystoma), Robert B. Page, Stephen R. Voss, Amy K. Samuels, Jeramiah J. Smith, Srikrishna Putta, Christopher K. Beachy

Biology Faculty Publications

BACKGROUND: Thyroid hormones (TH) induce gene expression programs that orchestrate amphibian metamorphosis. In contrast to anurans, many salamanders do not undergo metamorphosis in nature. However, they can be induced to undergo metamorphosis via exposure to thyroxine (T4). We induced metamorphosis in juvenile Mexican axolotls (Ambystoma mexicanum) using 5 and 50 nM T4, collected epidermal tissue from the head at four time points (Days 0, 2, 12, 28), and used microarray analysis to quantify mRNA abundances.

RESULTS: Individuals reared in the higher T4 concentration initiated morphological and transcriptional changes earlier and completed metamorphosis by Day 28. In contrast, initiation of metamorphosis …


Effect Of Thyroid Hormone Concentration On The Transcriptional Response Underlying Induced Metamorphosis In The Mexican Axolotl (Ambystoma), Robert B. Page, Stephen R. Voss, Amy K. Samuels, Jeramiah J. Smith, Srikrishna Putta, Christopher K. Beachy Feb 2008

Effect Of Thyroid Hormone Concentration On The Transcriptional Response Underlying Induced Metamorphosis In The Mexican Axolotl (Ambystoma), Robert B. Page, Stephen R. Voss, Amy K. Samuels, Jeramiah J. Smith, Srikrishna Putta, Christopher K. Beachy

Biology Faculty Publications

Background

Thyroid hormones (TH) induce gene expression programs that orchestrate amphibian metamorphosis. In contrast to anurans, many salamanders do not undergo metamorphosis in nature. However, they can be induced to undergo metamorphosis via exposure to thyroxine (T4). We induced metamorphosis in juvenile Mexican axolotls (Ambystoma mexicanum) using 5 and 50 nM T4, collected epidermal tissue from the head at four time points (Days 0, 2, 12, 28), and used microarray analysis to quantify mRNA abundances.

Results

Individuals reared in the higher T4 concentration initiated morphological and transcriptional changes earlier and completed metamorphosis by …


Neural Correlates Of Auditory Processing, Learning And Memory Formation In Songbirds, Raphael Pinaud, Thomas A. Terleph, Ryan D. Wynne, Liisa A. Tremere Feb 2008

Neural Correlates Of Auditory Processing, Learning And Memory Formation In Songbirds, Raphael Pinaud, Thomas A. Terleph, Ryan D. Wynne, Liisa A. Tremere

Biology Faculty Publications

Songbirds have emerged as powerful experimental models for the study of auditory processing of complex natural communication signals. Intact hearing is necessary for several behaviors in developing and adult animals including vocal learning, territorial defense, mate selection and individual recognition. These behaviors are thought to require the processing, discrimination and memorization of songs. Although much is known about the brain circuits that participate in sensorimotor (auditory-vocal) integration, especially the “songcontrol” system, less is known about the anatomical and functional organization of central auditory pathways. Here we discuss findings associated with a telencephalic auditory area known as the caudomedial nidopallium (NCM). …


A Novel Approach To Control Growth, Orientation, And Shape Of Human Osteoblasts, Jarema S. Czarnecki, Khalid Lafdi, Panagiotis A. Tsonis Feb 2008

A Novel Approach To Control Growth, Orientation, And Shape Of Human Osteoblasts, Jarema S. Czarnecki, Khalid Lafdi, Panagiotis A. Tsonis

Biology Faculty Publications

Carbon-based materials are considered to be promising materials as implants because of their unique mechanical and biocompatibility properties. The current paper investigates the use of carbon-based materials as a functional interface for tissue scaffolds and medical implants. Three basic parameters were explored such as graphene orientation, crystallinity and surface interaction. To explore the effect of the orientation, samples were made with and without a preferred carbon orientation. Conversely, the crystallinity was studied using graphitic and carbonaceous matrices. Fluorescent, confocal and environmental scanning microscopy was used to visualize cell response. The cell attachment, proliferation and elongation were prevalent on the unidirectional …


What Do Students Have To Say About Ecology And Evolution? Using Podcasting To Apply Integrative Biology Themes Across The Tree Of Life, Amy M. Treonis, Malcolm Hill, Theresa Dolson, Sue Mcginnis, Elizabeth Miles Jan 2008

What Do Students Have To Say About Ecology And Evolution? Using Podcasting To Apply Integrative Biology Themes Across The Tree Of Life, Amy M. Treonis, Malcolm Hill, Theresa Dolson, Sue Mcginnis, Elizabeth Miles

Biology Faculty Publications

We describe a versatile podcasting assignment that requires students to (i) review primary and secondary literature relating to an assigned organism with the goal of identifying the main features of its ecology and evolution, (ii) prepare an enhanced podcast about their organism, and (iii) critique peer podcasts. The goal of this assignment is for each student to gain a fuller appreciation for and understanding of biological diversity. This assignment will enhance students' research, technology, and communication skills while reinforcing the main themes of integrative biology.


Antiretroviral Pre-Exposure Prophylaxis Prevents Vaginal Transmission Of Hiv-1 In Humanized Blt Mice, Paul W. Denton, Jacob D. Estes, Zhifeng Sun, Florence A. Othieno, Bangdong L. Wei, Anja K. Wege, Daniel A. Powell, Deborah A. Payne, Ashley T. Haase, J. Victor Garcia Jan 2008

Antiretroviral Pre-Exposure Prophylaxis Prevents Vaginal Transmission Of Hiv-1 In Humanized Blt Mice, Paul W. Denton, Jacob D. Estes, Zhifeng Sun, Florence A. Othieno, Bangdong L. Wei, Anja K. Wege, Daniel A. Powell, Deborah A. Payne, Ashley T. Haase, J. Victor Garcia

Biology Faculty Publications

Background: Worldwide, vaginal transmission now accounts for more than half of newly acquired HIV-1 infections. Despite the urgency to develop and implement novel approaches capable of preventing HIV transmission, this process has been hindered by the lack of adequate small animal models for preclinical efficacy and safety testing. Given the importance of this route of transmission, we investigated the susceptibility of humanized mice to intravaginal HIV-1 infection.

Methods and Findings: We show that the female reproductive tract of humanized bone marrow–liver–thymus (BLT) mice is reconstituted with human CD4þ T and other relevant human cells, rendering these humanized mice …