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Biology Faculty Publications

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Articles 811 - 840 of 1366

Full-Text Articles in Biology

Opposing Mechanisms Drive Richness Patterns Of Core And Transient Bird Species, Jessica R. Coyle, Allen H. Hurlbert, Ethan P. White Apr 2013

Opposing Mechanisms Drive Richness Patterns Of Core And Transient Bird Species, Jessica R. Coyle, Allen H. Hurlbert, Ethan P. White

Biology Faculty Publications

Studies of biodiversity typically assume that all species are equivalent. However, some species in a community maintain viable populations in the study area, while others occur only occasionally as transient individuals. Here we show that North American bird communities can reliably be divided into core and transient species groups and that the richness of each group is driven by different processes. The richness of core species is influenced primarily by local environmental conditions, while the richness of transient species is influenced primarily by the heterogeneity of the surrounding landscape. This demonstrates that the well-known effects of the local environment and …


Rectal Transmission Of Transmitted/Founder Hiv-1 Is Efficiently Prevented By Topical 1% Tenofovir In Blt Humanized Mice, Morgan L. Chateau, Paul W. Denton, Michael D. Swanson, Ian Mcgowan, J. Victor Garcia Mar 2013

Rectal Transmission Of Transmitted/Founder Hiv-1 Is Efficiently Prevented By Topical 1% Tenofovir In Blt Humanized Mice, Morgan L. Chateau, Paul W. Denton, Michael D. Swanson, Ian Mcgowan, J. Victor Garcia

Biology Faculty Publications

Rectal microbicides are being developed to prevent new HIV infections in both men and women. We focused our in vivo preclinical efficacy study on rectally-applied tenofovir. BLT humanized mice (n = 43) were rectally inoculated with either the primary isolate HIV-1JRCSF or the MSM-derived transmitted/founder (T/F) virus HIV-1THRO within 30 minutes following treatment with topical 1% tenofovir or vehicle. Under our experimental conditions, in the absence of drug treatment we observed 50% and 60% rectal transmission by HIV-1JRCSF and HIV-1THRO, respectively. Topical tenofovir reduced rectal transmission to 8% (1/12; log rank p = 0.03) for HIV-1JRCSF and 0% (0/6; log …


The Advertisement Call Of The Poorly Known Leptodactylus Tapiti (Anura, Leptodactylidae), Reuber Albuquerque Brandão, Guilherme Fajardo Roldão Álvares, Rafael O. De Sá Feb 2013

The Advertisement Call Of The Poorly Known Leptodactylus Tapiti (Anura, Leptodactylidae), Reuber Albuquerque Brandão, Guilherme Fajardo Roldão Álvares, Rafael O. De Sá

Biology Faculty Publications

The genus Leptodactylus consists of approximately 80 species distributed in four nominal groups (Frost 2011). The fuscus group harbors approximately 30 small species with terrestrial nests, deposited in male built burrows on soft soils. Leptodactylus tapiti Sazima & Bokermann 1978 was described from Veadeiros, currently Alto Paraíso municipality, Goiás State, Brazil. The species is restricted to the region of Chapada dos Veadeiros (Frost 2011), where it occurs in areas of water-saturated soils associated with open fields (Sazima & Bokermann 1978). Since its original description, nothing was published about the species, and its advertisement call remains unknown. Herein, we describe its …


S-Adenosyl-L-Methionine Protects The Probiotic Yest, Saccharomyces Boulardii, From Acid-Induced Cell Death, Nicanor Austriaco, Vincent Cascio, Daniel Gittings, Kristen Merloni, David Laprade Feb 2013

S-Adenosyl-L-Methionine Protects The Probiotic Yest, Saccharomyces Boulardii, From Acid-Induced Cell Death, Nicanor Austriaco, Vincent Cascio, Daniel Gittings, Kristen Merloni, David Laprade

Biology Faculty Publications

Background

Saccharomyces boulardii is a probiotic yeast routinely used to prevent and to treat gastrointestinal disorders, including the antibiotic-associated diarrhea caused by Clostridium difficile infections. However, only 1-3% of the yeast administered orally is recovered alive in the feces suggesting that this yeast is unable to survive the acidic environment of the gastrointestinal tract.

Results

We provide evidence that suggests that S. boulardii undergoes programmed cell death (PCD) in acidic environments, which is accompanied by the generation of reactive oxygen species and the appearance of caspase-like activity. To better understand the mechanism of cell death at the molecular level, we …


Sensory Exploitation And Indicator Models May Explain Red Pelvic Spines In The Brook Stickleback, Culaea Inconstans, Andrew Hodgson, A. Ross Black, Ryan Hull Feb 2013

Sensory Exploitation And Indicator Models May Explain Red Pelvic Spines In The Brook Stickleback, Culaea Inconstans, Andrew Hodgson, A. Ross Black, Ryan Hull

Biology Faculty Publications

Background: Sensory bias models explaining the evolution of sexually selected traits predict that trait preferences evolve as an artifact of a pre-existing preference for certain components of the environment such as specifically coloured prey. Indicator models, in contrast, predict that sexually selected traits indicate mate condition. We investigate the potential for sensory exploitation and condition indication models to explain the evolution of what appears to be a recently evolved sexually selected trait. Question: Did red pelvic spine coloration in male Turnbull National Wildlife Refuge (TNWR) brook stickleback (Culaea inconstans) evolve to exploit a pre-existing sensory bias for red prey, thus …


A Microarray Analysis Of Gene Expression Patterns During Early Phases Of Newt Lens Regeneration, Konstantinos Sousounis, Christian S. Michel, Marc Bruckskotten, Nobuyasu Maki, Thilo Borchardt, Thomas Braun, Mario Looso, Panagiotis A. Tsonis Jan 2013

A Microarray Analysis Of Gene Expression Patterns During Early Phases Of Newt Lens Regeneration, Konstantinos Sousounis, Christian S. Michel, Marc Bruckskotten, Nobuyasu Maki, Thilo Borchardt, Thomas Braun, Mario Looso, Panagiotis A. Tsonis

Biology Faculty Publications

Purpose: Notophthalmus viridescens, the red-spotted newt, possesses tremendous regenerative capabilities. Among the tissues and organs newts can regenerate, the lens is regenerated via transdifferentiation of the pigment epithelial cells of the dorsal iris, following complete removal (lentectomy). Under normal conditions, the same cells from the ventral iris are not capable of regenerating. This study aims to further understand the initial signals of lens regeneration.


Revisiting The Relationship Between Regenerative Ability And Aging, Ashley W. Seifert, S. Randal Voss Jan 2013

Revisiting The Relationship Between Regenerative Ability And Aging, Ashley W. Seifert, S. Randal Voss

Biology Faculty Publications

Contrary to the longstanding view that newts (Notophthalamus viridescens), but not axolotls (Ambystoma mexicanum), can regenerate a lens, a recent report in BMC Biology by Panagiotis Tsonis and colleagues shows axolotls indeed possess this ability during early larval stages. In contrast, they show that zebrafish never posses this ability, even as embryos. This underscores the importance of comparing regenerative ability across species and reinforces the need to consider organ regeneration in the context of evolution, development, and aging.


Long-Term Data For Endemic Frog Genera Reveal Potential Conservation Crisis In The Bale Mountains, Ethiopia, David J. Gower, Roman K. Aberra, Silvia Schwaller, Malcolm J. Largen, Ben Collen, Stephen Spawls, Michele Menegon, Breda M. Zimkus, Rafael O. De Sá, Et Al. Jan 2013

Long-Term Data For Endemic Frog Genera Reveal Potential Conservation Crisis In The Bale Mountains, Ethiopia, David J. Gower, Roman K. Aberra, Silvia Schwaller, Malcolm J. Largen, Ben Collen, Stephen Spawls, Michele Menegon, Breda M. Zimkus, Rafael O. De Sá, Et Al.

Biology Faculty Publications

Populations of many frogs have declined alarmingly in recent years, placing nearly one third of the > 6,000 species under threat of extinction. Declines have been attributed largely to habitat loss, environmental degradation and/or infectious diseases such as chytridiomycosis. Many frogs undergo dramatic natural population fluctuations such that long-term data are required to determine population trends without undue influence of stochastic factors. We present long-term quantitative data (individuals encountered per person hour of searching) for four monotypic frog genera endemic to an Afromontane region of exceptional importance but growing conservation concern: one endemic to the Ethiopian highlands (Spinophrynoides osgoodi) and three …


Ovarian Cycle Activity Varies With Respect To Age And Social Status In Free-Ranging Elephants In Addo Elephant National Park, South Africa, Elizabeth Freeman, Jordana Meyer, Sarah Putman, Bruce A. Schulte, Janine Brown Jan 2013

Ovarian Cycle Activity Varies With Respect To Age And Social Status In Free-Ranging Elephants In Addo Elephant National Park, South Africa, Elizabeth Freeman, Jordana Meyer, Sarah Putman, Bruce A. Schulte, Janine Brown

Biology Faculty Publications

Free-ranging African elephants live in a fission–fusion society, at the centre of which is the matriarch. Matriarchs are generally older females that guide their families to resources and co-ordinate group defense. While much is known about elephant society, knowledge is generally lacking about how age affects the physiology of wild elephants. Investigation of the ovarian activity of free-ranging elephants could provide insight into the reproductive ageing process, with implications for population management. Faecal samples were collected from 46 individuals ranging in age from 14 to 60 years for a 2-year period, and progestagen metabolite analyses were used to examine relationships …


Genomics Of A Metamorphic Timing Qtl: Met1 Maps To A Unique Genomic Position And Regulates Morph And Species-Specific Patterns Of Brain Transcription, Robert B. Page, Meredith A. Boley, D. Kevin Kump, S. Randal Voss Jan 2013

Genomics Of A Metamorphic Timing Qtl: Met1 Maps To A Unique Genomic Position And Regulates Morph And Species-Specific Patterns Of Brain Transcription, Robert B. Page, Meredith A. Boley, D. Kevin Kump, S. Randal Voss

Biology Faculty Publications

Very little is known about genetic factors that regulate life history transitions during ontogeny. Closely related tiger salamanders (Ambystoma species complex) show extreme variation in metamorphic timing, with some species foregoing metamorphosis altogether, an adaptive trait called paedomorphosis. Previous studies identified a major effect QTL (met1) for metamorphic timing and expression of paedomorphosis in hybrid crosses between the biphasic Eastern tiger salamander (Ambystoma tigrinum tigrinum) and the paedomorphic Mexican axolotl (Ambystoma mexicanum). We used existing hybrid mapping panels and a newly created hybrid cross to map the met1 genomic region and determine the …


Reconstruction Of Family-Level Phylogenetic Relationships Within Demospongiae (Porifera) Using Nuclear Encoded Housekeeping Genes, Malcolm Hill, April L. Hill, Et. Al. Jan 2013

Reconstruction Of Family-Level Phylogenetic Relationships Within Demospongiae (Porifera) Using Nuclear Encoded Housekeeping Genes, Malcolm Hill, April L. Hill, Et. Al.

Biology Faculty Publications

Background: Demosponges are challenging for phylogenetic systematics because of their plastic and relatively simple morphologies and many deep divergences between major clades. To improve understanding of the phylogenetic relationships within Demospongiae, we sequenced and analyzed seven nuclear housekeeping genes involved in a variety of cellular functions from a diverse group of sponges.

Methodology/Principal Findings: We generated data from each of the four sponge classes (i.e., Calcarea, Demospongiae, Hexactinellida, and Homoscleromorpha), but focused on family-level relationships within demosponges. With data for 21 newly sampled families, our Maximum Likelihood and Bayesian-based approaches recovered previously phylogenetically defined taxa: Keratosap, Myxospongiae …


Trichoptera Of Mindoro, The Philippines I. New Species And Records From The Baroc River Catchment, Roxas, Oriental Mindoro (Insecta, Trichoptera), Hendrik Freitag, Wolfram Mey Jan 2013

Trichoptera Of Mindoro, The Philippines I. New Species And Records From The Baroc River Catchment, Roxas, Oriental Mindoro (Insecta, Trichoptera), Hendrik Freitag, Wolfram Mey

Biology Faculty Publications

The study of a collection of caddisflies from Mindoro yielded a total of 34 species. Eight species proved to be unknown taxa and are described in the present article as: Rhyacophila crenophysetis spec. nov., Agapetus parallelaria spec. nov., Stactobia roxasi spec. nov., Paduniella vicentis spec. nov., Paduniella prodita spec. nov., Psychomyia taugadensis spec. nov., Tinodes hypoplectis spec. nov., and Ecnomus biundularia spec. nov. A list of all collected species is provided.


A New Intertidal Shore Bug (Heteroptera: Saldidae) From The Philippines, Hendrik Freitag, Herbert Zettel, Clister V. Pangantihon Jan 2013

A New Intertidal Shore Bug (Heteroptera: Saldidae) From The Philippines, Hendrik Freitag, Herbert Zettel, Clister V. Pangantihon

Biology Faculty Publications

Salduncula carmencitae sp.n. is described, its habitus and the paramere and parandria of the male are illustrated. This shore bug was found on Mindanao Island, the Philippines, in the intertidal zone. Habitat and behaviour of the species are briefly described. The distinguishing diagnostic characters of species of Salduncula Brown, 1954 are discussed.


Ancyronyx Erichson, 1847 (Coleoptera, Elmidae) From Mindoro, Philippines, With Description Of The Larvae And Two New Species Using Dna Sequences For The Assignment Of The Developmental Stages, Hendrik Freitag Jan 2013

Ancyronyx Erichson, 1847 (Coleoptera, Elmidae) From Mindoro, Philippines, With Description Of The Larvae And Two New Species Using Dna Sequences For The Assignment Of The Developmental Stages, Hendrik Freitag

Biology Faculty Publications

Ancyronyx buhid sp. n. and Ancyronyx tamaraw sp. n. are described based on adults and larvae, matched using their cox1 or cob DNA sequence data. Additional records of Ancyronyx schillhammeri Jäch, 1994 and Ancyronyx minerva Freitag & Jäch, 2007 from Mindoro are listed. The previously unknown larva of Ancyronyx schillhammeri is also described here, aided by cox1 data. The new species and larval stages are described in detail and illustrated by SEM and stacked microscopic images. Keys to the adult and larval Ancyronyx species of Mindoro and an updated checklist of Philippine Ancyronyx species are provided. The usefulness as bioindicators, …


Hydraena (Hydraenopsis) Ateneo, New Species (Coleoptera, Hydraenidae) And Other Aquatic Polyphaga From A Small Habitat Patch In A Highly Urbanized Landscape Of Metro Manila, Philippines, Hendrik Freitag Jan 2013

Hydraena (Hydraenopsis) Ateneo, New Species (Coleoptera, Hydraenidae) And Other Aquatic Polyphaga From A Small Habitat Patch In A Highly Urbanized Landscape Of Metro Manila, Philippines, Hendrik Freitag

Biology Faculty Publications

Seven species of Hydraenidae, Hydrophilidae and Elmidae are recorded from temporary freshwater habitats at the Ateneo de Manila University Campus in the metropolitan area of Manila, Philippines. They were identified as Enochrus (Lumetus) fragiloides d’Orchymont, Helochares (Hydrobaticus) lepidus d’Orchymont, Helochares (Helochares) pallens (MacLeay), Hydraena (Hydraenopsis) scabra d’Orchymont, Hydraena (Hydraenopsis) palawanensis Freitag & Jäch (new record for Luzon Island), Stenelmis sp. A further hydraenid species was unknown to science and is newly described: Hydraena (Hydraenopsis) ateneo Freitag, sp. n. Aedeagus, gonocoxite, spermatheca, and female tergite X are illustrated by …


Pushing Taxonomy To Extiction?, Alessandro Minelli, Annemarie Ohler, Erna Aescht, Aaron Bauer, Lucio Bonato, Roger Bour, Marcelo Rodrigues De Carvalho, Rafael O. De Sá, Et Al. Jan 2013

Pushing Taxonomy To Extiction?, Alessandro Minelli, Annemarie Ohler, Erna Aescht, Aaron Bauer, Lucio Bonato, Roger Bour, Marcelo Rodrigues De Carvalho, Rafael O. De Sá, Et Al.

Biology Faculty Publications

Can we describe all species on Earth before they disappear? We argue that this is possible only by endowing taxonomy with professional manpower and appropriate material resources as required by big science.

Contrary to Costello et al.’s (CMS) (1) statements, taxonomy is not an easy discipline accessible to all through a smartphone. It requires exhaustive training and long familiarity with field, specimens and literature (2).

CMS’s argument is framed in terms of species numbers, but different, non-overlapping species concepts apply to bacteria, brambles and birds (3,4,5): “the species” as common unit of biodiversity does not exist (6).

Even ignoring this …


Comparative Study Of Environmental Factors Influencing Motor Task Learning And Memory Retention In Sighted And Blind Crayfish, Sonya M. Bierbower, Zhanna P. Shuranova, Kert Viele, Robin L. Cooper Jan 2013

Comparative Study Of Environmental Factors Influencing Motor Task Learning And Memory Retention In Sighted And Blind Crayfish, Sonya M. Bierbower, Zhanna P. Shuranova, Kert Viele, Robin L. Cooper

Biology Faculty Publications

In classical conditioning, an alteration in response occurs when two stimuli are regularly paired in close succession. An area of particular research interest is classical conditioning with a chemical signal and visual and/or tactile stimuli as the unconditional stimuli, to test manipulative and motor behaviors in a learning paradigm. A classical learning task chamber was developed to examine learning trends in a sighted surface-dwelling crayfish, Procambarus clarkii, and in a blind cave-dwelling crayfish, Orconectes australis packardi. We examined whether learning is influenced by environmental factors and/or reliance on different primary sensory modalities. Crayfish were trained to manipulate a large, cumbersome …


Genomics Of A Metamorphic Timing Qtl: Met1 Maps To A Unique Genomic Position And Regulates Morph And Species-Specific Patterns Of Brain Transcription, Robert B. Page, Meredith A. Boley, David K. Kump, Stephen R. Voss Jan 2013

Genomics Of A Metamorphic Timing Qtl: Met1 Maps To A Unique Genomic Position And Regulates Morph And Species-Specific Patterns Of Brain Transcription, Robert B. Page, Meredith A. Boley, David K. Kump, Stephen R. Voss

Biology Faculty Publications

Very little is known about genetic factors that regulate life history transitions during ontogeny. Closely related tiger salamanders (Ambystoma species complex) show extreme variation in metamorphic timing, with some species foregoing metamorphosis altogether, an adaptive trait called paedomorphosis. Previous studies identified a major effect quantitative trait locus (met1) for metamorphic timing and expression of paedomorphosis in hybrid crosses between the biphasic Eastern tiger salamander (Ambystoma tigrinum tigrinum) and the paedomorphic Mexican axolotl (Ambystoma mexicanum). We used existing hybrid mapping panels and a newly created hybrid cross to map the met1 genomic region and …


Pre-Binding Sites In The Mdr Of Cll: Potential Tumor Suppressor Regulation, Christine E. Cutucache, Javeed Iqbal, Philip Bierman, Robert Gregory Bociek, Dennis D. Weisenburger, Shantaram S. Joshi Jan 2013

Pre-Binding Sites In The Mdr Of Cll: Potential Tumor Suppressor Regulation, Christine E. Cutucache, Javeed Iqbal, Philip Bierman, Robert Gregory Bociek, Dennis D. Weisenburger, Shantaram S. Joshi

Biology Faculty Publications

Chronic lymphocytic leukemia [CLL] is the most common adult leukemia and is heterogeneous in clinical presentation. CLL cases present with various chromosomal aberrations, including 11q23, 14q32, 17p, and trisomy 12, with the most common abnormality being deletion of 13q14 [1]. Although monoallelic deletion of 13q14 is common, there is a subset of patients who have complete nullisomy at 13q14, a locus that has been hypothesized to contribute to CLL pa thogenesis [2] due to loss of tumor suppressors [DLEU and miR-15a/16-1].We hypothesized that deletion of both copies of 13q14 would lead to uncontrollable proliferation …


Sensitivity Of Grassland Plant Community Composition To Spatial Vs. Temporal Variation In Precipitation, Elsa E. Cleland, Scott L. Collins, Timothy L. Dickson, Emily C. Farrer, Katherine L. Gross, Laureano A. Gherardi, Lauren M. Hallett, Richard J. Hobbs, Joanna S. Hsu, Laura Turnball, Katharine N. Suding Jan 2013

Sensitivity Of Grassland Plant Community Composition To Spatial Vs. Temporal Variation In Precipitation, Elsa E. Cleland, Scott L. Collins, Timothy L. Dickson, Emily C. Farrer, Katherine L. Gross, Laureano A. Gherardi, Lauren M. Hallett, Richard J. Hobbs, Joanna S. Hsu, Laura Turnball, Katharine N. Suding

Biology Faculty Publications

Climate gradients shape spatial variation in the richness and composition of plant communities. Given future predicted changes in climate means and variability, and likely regional variation in the magnitudes of these changes, it is important to determine how temporal variation in climate influences temporal variation in plant community structure. Here, we evaluated how species richness, turnover, and composition of grassland plant communities responded to interannual variation in precipitation by synthesizing long-term data from grasslands across the United States. We found that mean annual precipitation (MAP) was apositive predictor of species richness across sites, but a positive temporal relationship between annual …


Characterization Of The Asian Citrus Psyllid Transcriptome, Justin Reese, Matthew K. Christenson, Nan Leng, Surya Saha, Brandi Cantarel, Magdalen Lindeberg, Cecilia Tamborindeguy, Justin Maccarthy, Andrew J. Trease, Steven V. Ready, Vincent M. David, Courtney Mccormick, Christian Haudenschild, Shunsheng Han, Shannon L. Johnson, Kent S. Shelby, Hong Huang, Blake R. Bextine, Robert G. Shatters, David G. Hall, Paul H. Davis, Wayne B. Hunter Jan 2013

Characterization Of The Asian Citrus Psyllid Transcriptome, Justin Reese, Matthew K. Christenson, Nan Leng, Surya Saha, Brandi Cantarel, Magdalen Lindeberg, Cecilia Tamborindeguy, Justin Maccarthy, Andrew J. Trease, Steven V. Ready, Vincent M. David, Courtney Mccormick, Christian Haudenschild, Shunsheng Han, Shannon L. Johnson, Kent S. Shelby, Hong Huang, Blake R. Bextine, Robert G. Shatters, David G. Hall, Paul H. Davis, Wayne B. Hunter

Biology Faculty Publications

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae) is a vector for the causative agents of Huanglongbing, which threatens citrus production worldwide. This study reports and discusses the first D. citri transcriptomes, encompassing the three main life stages of D. citri, egg, nymph and adult. The transcriptomes were annotated using Gene Ontology (GO) and insecticide-related genes within each life stage were identified to aid the development of future D. citri insecticides. Transcriptome assemblies and other sequence data are available for download at the International Asian Citrus Psyllid Genome Consortium website [http://psyllid.org/download] and at NCBI [http://www.ncbi.nlm.nih.gov/bioproject/29447].


In Vivo Analysis Of Highly Conserved Nef Activities In Hiv-1 Replication And Pathogenesis, Richard L. Watkins, Wei Zou, Paul W. Denton, John F. Krisko, John L. Foster, J. Victor Garcia Jan 2013

In Vivo Analysis Of Highly Conserved Nef Activities In Hiv-1 Replication And Pathogenesis, Richard L. Watkins, Wei Zou, Paul W. Denton, John F. Krisko, John L. Foster, J. Victor Garcia

Biology Faculty Publications

Background: The HIV-1 accessory protein, Nef, is decisive for progression to AIDS. In vitro characterization of the protein has described many Nef activities of unknown in vivo significance including CD4 downregulation and a number of activities that depend on Nef interacting with host SH3 domain proteins. Here, we use the BLT humanized mouse model of HIV-1 infection to assess their impact on viral replication and pathogenesis and the selection pressure to restore these activities using enforced in vivo evolution.

Results: We followed the evolution of HIV-1LAI (LAI) with a frame-shifted nef (LAINeffs) during infection of BLT mice. LAINeffs …


Salamander Hox Clusters Contain Repetitive Dna And Expanded Non-Coding Regions: A Typical Hox Structure For Non-Mammalian Tetrapod Vertebrates?, Stephen Randal Voss, Srikrishna Putta, John A. Walker, Jeremiah J. Smith, Nobuyasu Maki, Panagiotis A. Tsonis Jan 2013

Salamander Hox Clusters Contain Repetitive Dna And Expanded Non-Coding Regions: A Typical Hox Structure For Non-Mammalian Tetrapod Vertebrates?, Stephen Randal Voss, Srikrishna Putta, John A. Walker, Jeremiah J. Smith, Nobuyasu Maki, Panagiotis A. Tsonis

Biology Faculty Publications

Hox genes encode transcription factors that regulate embryonic and post-embryonic developmental processes. The expression of Hox genes is regulated in part by the tight, spatial arrangement of conserved coding and non-coding sequences. The potential for evolutionary changes in Hox cluster structure is thought to be low among vertebrates; however, recent studies of a few non-mammalian taxa suggest greater variation than originally thought. Using next generation sequencing of large genomic fragments (>100 kb) from the red spotted newt (Notophthalamus viridescens), we found that the arrangement of Hox cluster genes was conserved relative to orthologous regions from other vertebrates, but the …


How Species Richness And Total Abundance Constrain The Distribution Of Abundance, Kenneth J. Locey, Ethan P. White Jan 2013

How Species Richness And Total Abundance Constrain The Distribution Of Abundance, Kenneth J. Locey, Ethan P. White

Biology Faculty Publications

The species abundance distribution (SAD) is one of the most intensively studied distributions in ecology and its hollow-curve shape is one of ecology’s most general patterns. We examine the SAD in the context of all possible forms having the same richness (S) and total abundance (N), i.e. the feasible set. We find that feasible sets are dominated by similarly-shaped hollow-curves, most of which are highly correlated with empirical SADs (most R2 values > 75%), revealing a strong influence of N and S on the form of the SAD and an a priori explanation for the ubiquitous hollow-curve. Empirical SADs are often …


Life History, C. W. Fox, Frank J. Messina Jan 2013

Life History, C. W. Fox, Frank J. Messina

Biology Faculty Publications

No abstract provided.


A Hunter Virus That Targets Both Infected Cells And Hiv Free Virions: Implications For Therapy, Cody Greer, Gisela García-Ramos Dec 2012

A Hunter Virus That Targets Both Infected Cells And Hiv Free Virions: Implications For Therapy, Cody Greer, Gisela García-Ramos

Biology Faculty Publications

The design of 'hunter' viruses aimed at destroying human immunodeficiency virus (HIV) infected cells is an active area of research that has produced promising results in vitro. Hunters are designed to target exposed viral envelope proteins in the membranes of infected cells, but there is evidence that the hunter may also target envelope proteins of free HIV, inducing virus-virus fusion. In order to predict the effects of this fusion on therapy outcomes and determine whether fusion ability is advantageous for hunter virus design, we have constructed a model to account for the possibility of hunter-HIV fusion. The study was based …


Molecular Phylogeny Of Microhylid Frogs (Anura: Microhylidae) With Emphasis On Relationships Among New World Genera, Rafael O. De Sá, Jeffrey W. Streicher, Relebohile Sekonyela, Mauricio C. Forlani, Simon P. Loader, Eli Greenbaum, Stephen Richards, Célio F.B. Haddad Dec 2012

Molecular Phylogeny Of Microhylid Frogs (Anura: Microhylidae) With Emphasis On Relationships Among New World Genera, Rafael O. De Sá, Jeffrey W. Streicher, Relebohile Sekonyela, Mauricio C. Forlani, Simon P. Loader, Eli Greenbaum, Stephen Richards, Célio F.B. Haddad

Biology Faculty Publications

Background: Over the last ten years we have seen great efforts focused on revising amphibian systematics. Phylogenetic reconstructions derived from DNA sequence data have played a central role in these revisionary studies but have typically under-sampled the diverse frog family Microhylidae. Here, we present a detailed phylogenetic study focused on expanding previous hypotheses of relationships within this cosmopolitan family. Specifically, we placed an emphasis on assessing relationships among New World genera and those taxa with uncertain phylogenetic affinities (i.e., incertae sedis).

Results: One mitochondrial and three nuclear genes (about 2.8 kb) were sequenced to assess phylogenetic relationships. We utilized an …


Localizing Brain Regions Associated With Female Mate Preference Behavior In A Swordtail, Ryan Y. Wong, Mary E. Ramsey, Molly E. Cummings Nov 2012

Localizing Brain Regions Associated With Female Mate Preference Behavior In A Swordtail, Ryan Y. Wong, Mary E. Ramsey, Molly E. Cummings

Biology Faculty Publications

Female mate choice behavior is a critical component of sexual selection, yet identifying the neural basis of this behavior is largely unresolved. Previous studies have implicated sensory processing and hypothalamic brain regions during female mate choice and there is a conserved network of brain regions (Social Behavior Network, SBN) that underlies sexual behaviors. However, we are only beginning to understand the role this network has in pre-copulatory female mate choice. Using in situ hybridization, we identify brain regions associated with mate preference in female Xiphophorus nigrensis, a swordtail species with a female choice mating system. We measure gene expression in …


Toward The Beginning Of Time: Circadian Rhythms In Metabolism Precede Rhythms In Clock Gene Expression In Mouse Embryonic Stem Cells, Jiffin K. Paulose, Edmund B. Rucker Iii, Vincent M. Cassone Nov 2012

Toward The Beginning Of Time: Circadian Rhythms In Metabolism Precede Rhythms In Clock Gene Expression In Mouse Embryonic Stem Cells, Jiffin K. Paulose, Edmund B. Rucker Iii, Vincent M. Cassone

Biology Faculty Publications

The appearance, progression, and potential role for circadian rhythms during early development have previously focused mainly on the suprachiasmatic nucleus (SCN) and peri- and postnatal expression of canonical clock genes. More recently, gene expression studies in embryonic stem cells have shown that some clock genes are expressed in undifferentiated cells; however rhythmicity was only established when cells are directed toward a neural fate. These studies also concluded that a functional clock is not present in ESCs, based solely on their gene expression. The null hypothesis underlying the present study is that embryonic stem cells become rhythmic in both clock gene …


Physiological Epicotyl Dormancy And Recalcitrant Storage Behaviour In Seeds Of Two Tropical Fabaceae (Subfamily Caesalpinioideae) Species, K. M. G. Gehan Jayasuriya, Asanga S. T. B. Wijetunga, Jerry M. Baskin, Carol C. Baskin Nov 2012

Physiological Epicotyl Dormancy And Recalcitrant Storage Behaviour In Seeds Of Two Tropical Fabaceae (Subfamily Caesalpinioideae) Species, K. M. G. Gehan Jayasuriya, Asanga S. T. B. Wijetunga, Jerry M. Baskin, Carol C. Baskin

Biology Faculty Publications

BACKGROUND AND AIMS: Physiological epicotyl dormancy in which the epicotyl elongates inside the seed before the shoot emerges has been reported for only a few tropical rainforest species, all of which are trees that produce recalcitrant seeds. In studies on seeds of Fabaceae in Sri Lanka, we observed a considerable time delay in shoot emergence following root emergence in seeds of the introduced caesalpinioid legumes Brownea coccinea and Cynometra cauliflora. Thus, our aim was to determine if seeds of these two tropical rainforest trees have physiological epicotyl dormancy, and also if they are recalcitrant, i.e. desiccation sensitive.

METHODOLOGY: Fresh seeds …