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Full-Text Articles in Life Sciences

Patchiness Of Ciliate Communities Sampled At Varying Spatial Scales Along The New England Shelf, Jean-David Grattepanche, George B. Mcmanus, Laura A. Katz Dec 2016

Patchiness Of Ciliate Communities Sampled At Varying Spatial Scales Along The New England Shelf, Jean-David Grattepanche, George B. Mcmanus, Laura A. Katz

Biological Sciences: Faculty Publications

Although protists (microbial eukaryotes) provide an important link between bacteria and Metazoa in food webs, we do not yet have a clear understanding of the spatial scales on which protist diversity varies. Here, we use a combination of DNA fingerprinting (denaturant gradient gel electrophoresis or DGGE) and high-throughput sequencing (HTS) to assess the ciliate community in the class Spirotrichea at varying scales of 1–3 km sampled in three locations separated by at least 25 km—offshore, midshelf and inshore—along the New England shelf. Analyses of both abundant community (DGGE) and the total community (HTS) members reveal that: 1) ciliate communities are …


Profiling The Macrofilaricidal Effects Of Flubendazole On Adult Female Brugia Malayi Using Rnaseq, Maeghan O'Neill, Cristina Ballesteros, Lucienne Tritten, Erica Burkman, Weam I. Zaky, Jianguo Xia, Andrew Moorhead, Steven A. Williams, Timothy G. Geary Oct 2016

Profiling The Macrofilaricidal Effects Of Flubendazole On Adult Female Brugia Malayi Using Rnaseq, Maeghan O'Neill, Cristina Ballesteros, Lucienne Tritten, Erica Burkman, Weam I. Zaky, Jianguo Xia, Andrew Moorhead, Steven A. Williams, Timothy G. Geary

Biological Sciences: Faculty Publications

The use of microfilaricidal drugs for the control of onchocerciasis and lymphatic filariasis (LF) necessitates prolonged yearly dosing. Prospects for elimination or eradication of these diseases would be enhanced by the availability of a macrofilaricidal drug. Flubendazole (FLBZ), a benzimidazole anthel- mintic, is an appealing candidate. FLBZ has demonstrated potent macrofilaricidal effects in a number of experimental rodent models and in one human trial. Unfortunately, FLBZ was deemed unsatisfactory for use in mass drug administration campaigns due to its limited oral bioavailability. A new formulation that enables sufficient bioavailability following oral administration could render FLBZ an effective treatment for onchocerciasis …


The Effects Of Ivermectin On Brugia Malayi Females In Vitro: A Transcriptomic Approach, Cristina Ballesteros, Lucienne Tritten, Maeghan O'Neill, Erica Burkman, Weam I. Zaky, Jianguo Xia, Andrew Moorhead, Steven A. Williams, Timothy G. Geary Aug 2016

The Effects Of Ivermectin On Brugia Malayi Females In Vitro: A Transcriptomic Approach, Cristina Ballesteros, Lucienne Tritten, Maeghan O'Neill, Erica Burkman, Weam I. Zaky, Jianguo Xia, Andrew Moorhead, Steven A. Williams, Timothy G. Geary

Biological Sciences: Faculty Publications

Lymphatic filariasis and onchocerciasis are tropical diseases caused by infections with parasitic nematodes. Resulting chronic diseases can be strongly blinding and disfiguring, and contribute to an entrenched cycle of poverty in affected populations. Ivermectin is one of the pivotal drugs used to control these infections. The mechanism of antifilarial action of the drug is incompletely resolved. It kills circulating larval stages (microfilariae), but only reversibly sterilizes adult worms without killing them. Our limited understanding of the involved mechanisms hampers treatment optimization and sustainability of the efficacy of the drug, and investigations into its pharmacology are of paramount importance. Working with …


Gfap-Positive Radial Glial Cells Are An Essential Progenitor Population For Later-Born Neurons And Glia In The Zebrafish Spinal Cord, Kimberly Johnson, Jessica Barragan, Sarah Bashiruddin, Cody J. Smith, Chelsea Tyrrell, Michael J. Parsons, Rosemarie Doris, Sarah Kucenas, Gerald B. Downes, Carla M. Velez, Caitlin Schneider, Catalina Sakai, Narendra Pathak, Katrina Anderson, Rachael Stein, Stephen H. Devoto, Jeff S. Mumm, Michael J.F. Barresi Jul 2016

Gfap-Positive Radial Glial Cells Are An Essential Progenitor Population For Later-Born Neurons And Glia In The Zebrafish Spinal Cord, Kimberly Johnson, Jessica Barragan, Sarah Bashiruddin, Cody J. Smith, Chelsea Tyrrell, Michael J. Parsons, Rosemarie Doris, Sarah Kucenas, Gerald B. Downes, Carla M. Velez, Caitlin Schneider, Catalina Sakai, Narendra Pathak, Katrina Anderson, Rachael Stein, Stephen H. Devoto, Jeff S. Mumm, Michael J.F. Barresi

Biological Sciences: Faculty Publications

Radial glial cells are presumptive neural stem cells (NSCs) in the developing nervous system. The direct requirement of radial glia for the generation of a diverse array of neuronal and glial subtypes, however, has not been tested. We employed two novel transgenic zebrafish lines and endogenous markers of NSCs and radial glia to show for the first time that radial glia are essential for neurogenesis during development. By using the gfap promoter to drive expression of nuclear localized mCherry we discerned two distinct radial glial-derived cell types: a major nestin+/Sox2+ subtype with strong gfap promoter activity and a minor Sox2+ …


Radial Glia Inhibit Peripheral Glial Infiltration Into The Spinal Cord At Motor Exit Point Transition Zones, Cody J. Smith, Kimberly Johnson, Taylor G. Welsh, Michael J.F. Barresi, Sarah Kucenas Jul 2016

Radial Glia Inhibit Peripheral Glial Infiltration Into The Spinal Cord At Motor Exit Point Transition Zones, Cody J. Smith, Kimberly Johnson, Taylor G. Welsh, Michael J.F. Barresi, Sarah Kucenas

Biological Sciences: Faculty Publications

In the mature vertebrate nervous system, central and peripheral nervous system (CNS and PNS, respectively) GLIA myelinate distinct motor axon domains at the motor exit point transition zone (MEP TZ). How these cells preferentially associate with and myelinate discrete, non-overlapping CNS versus PNS axonal segments, is unknown. Using in vivo imaging and genetic cell ablation in zebrafish, we demonstrate that radial glia restrict migration of PNS glia into the spinal cord during development. Prior to development of radial glial endfeet, peripheral cells freely migrate back and forth across the MEP TZ. However, upon maturation, peripherally located cells never enter the …


Absence Of The Filarial Endosymbiont Wolbachia In Seal Heartworm (Acanthocheilonema Spirocauda) But Evidence Of Ancient Lateral Gene Transfer, Caroline D. Keroack, Jenna Irene Wurster, Caroline G. Decker, Kalini M. Williams, Barton E. Slatko, Jeremy M. Forster, Steven A. Williams Jun 2016

Absence Of The Filarial Endosymbiont Wolbachia In Seal Heartworm (Acanthocheilonema Spirocauda) But Evidence Of Ancient Lateral Gene Transfer, Caroline D. Keroack, Jenna Irene Wurster, Caroline G. Decker, Kalini M. Williams, Barton E. Slatko, Jeremy M. Forster, Steven A. Williams

Biological Sciences: Faculty Publications

The symbiotic relationship of Wolbachia spp. was first observed in insects and subsequently in many parasitic filarial nematodes. This bacterium is believed to provide metabolic and developmental assistance to filarial parasitic nematodes, although the exact nature of this relationship remains to be fully elucidated. While Wolbachia is present in most filarial nematodes in the familyOnchocercidae, it is absent in several disparate species such as the human parasite Loa loa. All tested members of the genusAcanthocheilonema, such as Acanthocheilonema viteae, have been shown to lack Wolbachia. Consistent with this, we show thatWolbachia is absent from the seal heartworm (Acanthocheilonema spirocauda), but …


Increased Androgenic Sensitivity In The Hind Limb Muscular System Marks The Evolution Of A Derived Gestural Display, Lisa A. Mangiamele, Matthew J. Fuxjager, Eric R. Schuppe, Rebecca S. Taylor, Walter Hödl, Doris Preininger May 2016

Increased Androgenic Sensitivity In The Hind Limb Muscular System Marks The Evolution Of A Derived Gestural Display, Lisa A. Mangiamele, Matthew J. Fuxjager, Eric R. Schuppe, Rebecca S. Taylor, Walter Hödl, Doris Preininger

Biological Sciences: Faculty Publications

Physical gestures are prominent features of many species’ multi- modal displays, yet how evolution incorporates body and leg movements into animal signaling repertoires is unclear. Andro- genic hormones modulate the production of reproductive signals and sexual motor skills in many vertebrates; therefore, one possi- bility is that selection for physical signals drives the evolution of androgenic sensitivity in select neuromotor pathways. We exam- ined this issue in the Bornean rock frog (Staurois parvus, family: Ranidae). Males court females and compete with rivals by per- forming both vocalizations and hind limb gestural signals, called “foot flags.” Foot flagging is a derived …


Phenotypic And Molecular Analysis Of The Effect Of 20-Hydroxyecdysone On The Human Filarial Parasite Brugia Malayi, Amruta S. Mhashilkar, Swamy R. Adapa, Rays H.Y. Jiang, Steven A. Williams, Weam I. Zaky, Barton E. Slatko, Ashley N. Luck, Andrew Moorhead, Thomas R. Unnasch May 2016

Phenotypic And Molecular Analysis Of The Effect Of 20-Hydroxyecdysone On The Human Filarial Parasite Brugia Malayi, Amruta S. Mhashilkar, Swamy R. Adapa, Rays H.Y. Jiang, Steven A. Williams, Weam I. Zaky, Barton E. Slatko, Ashley N. Luck, Andrew Moorhead, Thomas R. Unnasch

Biological Sciences: Faculty Publications

A homologue of the ecdysone receptor has been identified and shown to be responsive to 20- hydroxyecdysone in Brugia malayi. However, the role of this master regulator of insect development has not been delineated in filarial nematodes. Gravid adult female B. malayi cultured in the presence of 20-hydroxyecdysone produced significantly more microfilariae and abortive immature progeny than control worms, implicating the ecdysone receptor in regulation of embryogenesis and microfilarial development. Transcriptome analyses identified 30 genes whose expression was significantly up-regulated in 20-hydroxyecdysone-treated parasites compared with untreated controls. Of these, 18% were identified to be regulating transcription. A comparative proteomic analysis …


Nuclear Architecture And Patterns Of Molecular Evolution Are Correlated In The Ciliate Chilodonella Uncinata, Xyrus X. Maurer-Alcalá, Laura A. Katz Apr 2016

Nuclear Architecture And Patterns Of Molecular Evolution Are Correlated In The Ciliate Chilodonella Uncinata, Xyrus X. Maurer-Alcalá, Laura A. Katz

Biological Sciences: Faculty Publications

The relationship between nuclear architecture and patterns of molecular evolution in lineages across the eukaryotic tree of life is not well understood, partly because molecular evolution is traditionally explored as changes in base pairs along a linear sequence without considering the context of nuclear position of chromosomes. The ciliate Chilodonella uncinata is an ideal system to address the relationship between nuclear architecture and patterns of molecular evolution as the somatic macronucleus of this ciliate is composed of a peripheral DNA-rich area (orthomere) and a DNA-poor central region (paramere) to form a “heteromeric” macronucleus. Moreover, because the somatic chromosomes of C. …


A Novel Xenomonitoring Technique Using Mosquito Excreta/Feces For The Detection Of Filarial Parasites And Malaria, Nils Pilotte, Weam I. Zaky, Brian P. Abrams, Dave D. Chadee, Steven A. Williams Apr 2016

A Novel Xenomonitoring Technique Using Mosquito Excreta/Feces For The Detection Of Filarial Parasites And Malaria, Nils Pilotte, Weam I. Zaky, Brian P. Abrams, Dave D. Chadee, Steven A. Williams

Biological Sciences: Faculty Publications

Given the continued successes of the world’s lymphatic filariasis (LF) elimination programs and the growing successes of many malaria elimination efforts, the necessity of low cost tools and methodologies applicable to long-term disease surveillance is greater than ever before. As many countries reach the end of their LF mass drug administration programs and a growing number of countries realize unprecedented successes in their malaria interven- tion efforts, the need for practical molecular xenomonitoring (MX), capable of providing surveillance for disease recrudescence in settings of decreased parasite prevalence is increasingly clear. Current protocols, however, require testing of mosquitoes in pools of …


Improved Pcr-Based Detection Of Soil Transmitted Helminth Infections Using A Next-Generation Sequencing Approach To Assay Design, Nils Pilotte, Marina Papaiakovou, Jessica R. Grant, Lou Ann Bierwert, Stacey Llewllyn, James S. Mccarthy, Steven A. Williams Mar 2016

Improved Pcr-Based Detection Of Soil Transmitted Helminth Infections Using A Next-Generation Sequencing Approach To Assay Design, Nils Pilotte, Marina Papaiakovou, Jessica R. Grant, Lou Ann Bierwert, Stacey Llewllyn, James S. Mccarthy, Steven A. Williams

Biological Sciences: Faculty Publications

The soil transmitted helminths are a group of parasitic worms responsible for extensive mor- bidity in many of the world’s most economically depressed locations. With growing empha- sis on disease mapping and eradication, the availability of accurate and cost-effective diagnostic measures is of paramount importance to global control and elimination efforts. While real-time PCR-based molecular detection assays have shown great promise, to date, these assays have utilized sub-optimal targets. By performing next-generation sequencing- based repeat analyses, we have identified high copy-number, non-coding DNA sequences from a series of soil transmitted pathogens. We have used these repetitive DNA elements as targets …


Human Xq28 Inversion Polymorphism: From Sex Linkage To Genomics - A Genetic Mother Lode, Cait S. Kirby, Natalie Kolber, Asmaa M. Salih Almohaidi, Lou Ann Bierwert, Lori Saunders, Steven Williams, Robert Merritt Mar 2016

Human Xq28 Inversion Polymorphism: From Sex Linkage To Genomics - A Genetic Mother Lode, Cait S. Kirby, Natalie Kolber, Asmaa M. Salih Almohaidi, Lou Ann Bierwert, Lori Saunders, Steven Williams, Robert Merritt

Biological Sciences: Faculty Publications

An inversion polymorphism of the filamin and emerin genes at the tip of the long arm of the human X-chromosome serves as the basis of an investigative laboratory in which students learn something new about their own genomes. Long, nearly identical inverted repeats flanking the filamin and emerin genes illustrate how repetitive elements can lead to alterations in genome structure (inversions) through nonallelic homologous recombination. The near identity of the inverted repeats is an example of concerted evolution through gene conversion. While the laboratory in its entirety is designed for college level genetics courses, portions of the laboratory are appropriate …


Estrogens Suppress A Behavioral Phenotype In Zebrafish Mutants Of The Autism Risk Gene, Cntnap2, Ellen J. Hoffman, Katherine J. Turner, Joseph M. Fernandez, Daniel Cifuentes, Marcus Ghosh, Sundas Ijaz, Roshan A. Jain, Fumi Kubo, Brent R. Bill, Herwig Baier, Michael Granato, Michael J.F. Barresi, Stephen W. Wilson, Jason Rihel, Matthew W. State, Antonio J. Giraldez Feb 2016

Estrogens Suppress A Behavioral Phenotype In Zebrafish Mutants Of The Autism Risk Gene, Cntnap2, Ellen J. Hoffman, Katherine J. Turner, Joseph M. Fernandez, Daniel Cifuentes, Marcus Ghosh, Sundas Ijaz, Roshan A. Jain, Fumi Kubo, Brent R. Bill, Herwig Baier, Michael Granato, Michael J.F. Barresi, Stephen W. Wilson, Jason Rihel, Matthew W. State, Antonio J. Giraldez

Biological Sciences: Faculty Publications

Autism spectrum disorders (ASDs) are a group of devastating neurodevelopmental syndromes that affect up to 1 in 68 children. Despite advances in the identification of ASD risk genes, the mechanisms underlying ASDs remain unknown. Homozygous loss-of-function mutations in Contactin Associated Protein-like 2 (CNTNAP2) are strongly linked to ASDs. Here we investigate the function of Cntnap2 and undertake pharmacological screens to identify phenotypic suppressors. We find that zebrafish cntnap2 mutants display GABAergic deficits, particularly in the forebrain, and sensitivity to drug-induced seizures. High-throughput behavioral profiling identifies nighttime hyperactivity in cntnap2 mutants, while pharmacological testing reveals dysregulation of GABAergic and glutamatergic systems. …


The Effect Of In Vitro Cultivation On The Transcriptome Of Adult Brugia Malayi, Cristina Ballesteros, Lucienne Tritten, Maeghan O’Neill, Erica Burkman, Weam I. Zaky, Jianguo Xia, Andrew Moorhead, Steven A. Williams, Timothy G. Geary Jan 2016

The Effect Of In Vitro Cultivation On The Transcriptome Of Adult Brugia Malayi, Cristina Ballesteros, Lucienne Tritten, Maeghan O’Neill, Erica Burkman, Weam I. Zaky, Jianguo Xia, Andrew Moorhead, Steven A. Williams, Timothy G. Geary

Biological Sciences: Faculty Publications

Infections with filarial worms cause serious physical impairment and affect tens of millions of people in tropical and subtropical countries. To better understand the biology and phar- macology of these parasites, Brugia malayi is often used as a model. This parasite can be maintained in the laboratory in Mongolian jirds, enabling researchers to test drugs in vivoand in vitro, among other studies. The effects of removing worms from their hosts and cul- turing them may affect many aspects of their physiology, including response to drugs, but the extent to which the worms undergo changes during culture has remained unknown. Using …


The Effect Of In Vitro Cultivation On The Transcriptome Of Adult Brugia Malayi, Cristina Ballesteros, Lucienne Tritten, Maeghan O'Neill, Erica Burkman, Weam I. Zaky, Jianguo Xia, Andrew Moorhead, Steven A. Williams, Timothy G. Geary Jan 2016

The Effect Of In Vitro Cultivation On The Transcriptome Of Adult Brugia Malayi, Cristina Ballesteros, Lucienne Tritten, Maeghan O'Neill, Erica Burkman, Weam I. Zaky, Jianguo Xia, Andrew Moorhead, Steven A. Williams, Timothy G. Geary

Biological Sciences: Faculty Publications

Filarial nematodes cause serious and debilitating infections in human populations of tropical countries, contributing to an entrenched cycle of poverty. Only one human filarial parasite, Brugia malayi, can be maintained in rodents in the laboratory setting. It has been a widely used model organism in experiments that employ culture systems, the impact of which on the worms is unknown.


Consequences Of Elevated Salt Concentrations Expression Profiles In The Rhizobium S. Meliloti 1021 Likely Involved In Heat And Desiccation Stress, Jan A.C. Vriezen, Caroline M. Finn Jan 2016

Consequences Of Elevated Salt Concentrations Expression Profiles In The Rhizobium S. Meliloti 1021 Likely Involved In Heat And Desiccation Stress, Jan A.C. Vriezen, Caroline M. Finn

Biological Sciences: Faculty Publications

No abstract provided.


Appearance Of Membrane Compromised, Viable But Not Culturable And Culturable Rhizobial Cells As A Consequence Of Desiccation, Jan A.C. Vriezen, Frans J. De Bruijn Jan 2016

Appearance Of Membrane Compromised, Viable But Not Culturable And Culturable Rhizobial Cells As A Consequence Of Desiccation, Jan A.C. Vriezen, Frans J. De Bruijn

Biological Sciences: Faculty Publications

For agricultural purposes, drought related stresses negatively affect the Rhizobiaceae in at least three ways. Firstly, rhizobial populations are affected by desertification of agricultural soils. Secondly, the quality of dry-base inocula, also called formula, is negatively affected by a drying step, and thirdly, rhizosphere bacteria protect crop-plants against drought. Although survival of cultivatable bacteria has been studied intensively in dry-base seed inocula and in-vitro, thus far research has only marginally addressed the bacterial cell, its cellular structures and physiology. Many questions remain regarding the sensing of and physiological response of rhizobia to desiccation. This review will focus on the three …