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Full-Text Articles in Life Sciences

Evolutionary Analyses Of Visual Opsin Genes In Frogs And Toads: Diversity, Duplication, And Positive Selection, Ryan K. Schott, Leah Perez, Matthew Kwiatkowski, Vance Imhoff, Jennifer M. Gumm Jan 2022

Evolutionary Analyses Of Visual Opsin Genes In Frogs And Toads: Diversity, Duplication, And Positive Selection, Ryan K. Schott, Leah Perez, Matthew Kwiatkowski, Vance Imhoff, Jennifer M. Gumm

Faculty Publications

Among major vertebrate groups, anurans (frogs and toads) are understudied with regard to their visual systems, and little is known about variation among species that differ in ecology. We sampled North American anurans representing diverse evolutionary and life histories that likely possess visual systems adapted to meet different ecological needs. Using standard molecular techniques, visual opsin genes, which encode the protein component of visual pigments, were obtained from anuran retinas. Additionally, we extracted the visual opsins from publicly available genome and transcriptome assemblies, further increasing the phylogenetic and ecological diversity of our dataset to 33 species in total. We found …


Factors Related To Species Richness, Endemism, And Conservation Status Of The Herpetofauna (Amphibia And Reptilia) Of Mexican States, Geoffrey R. Smith, Julio A. Lemos-Espinal Jan 2022

Factors Related To Species Richness, Endemism, And Conservation Status Of The Herpetofauna (Amphibia And Reptilia) Of Mexican States, Geoffrey R. Smith, Julio A. Lemos-Espinal

Faculty Publications

No abstract provided.


Electrophysiological Responses To Conspecific Odorants In Xenopus Laevis Show Potential For Chemical Signaling, Heather J. Rhodes, Melanie Amo Jan 2022

Electrophysiological Responses To Conspecific Odorants In Xenopus Laevis Show Potential For Chemical Signaling, Heather J. Rhodes, Melanie Amo

Faculty Publications

No abstract provided.


Panoramic Spatial Vision In The Bay Scallop Argopecten Irradians, Daniel R. Chappell, Tyler M. Horan, Daniel Isaac Speiser Nov 2021

Panoramic Spatial Vision In The Bay Scallop Argopecten Irradians, Daniel R. Chappell, Tyler M. Horan, Daniel Isaac Speiser

Faculty Publications

We have a growing understanding of the light-sensing organs and light-influenced behaviours of animals with distributed visual systems, but we have yet to learn how these animals convert visual input into behavioural output. It has been suggested they consolidate visual information early in their sensory-motor pathways, resulting in them being able to detect visual cues (spatial resolution) without being able to locate them (spatial vision). To explore how an animal with dozens of eyes processes visual information, we analysed the responses of the bay scallop Argopecten irradians to both static and rotating visual stimuli. We found A. irradians distinguish between …


Cetacean Acousticwelfare In Wild And Managed-Care Settings: Gaps And Opportunities, Paige E. Stevens, Heather Hill, Jason N. Bruck Nov 2021

Cetacean Acousticwelfare In Wild And Managed-Care Settings: Gaps And Opportunities, Paige E. Stevens, Heather Hill, Jason N. Bruck

Faculty Publications

Cetaceans are potentially at risk of poor welfare due to the animals’ natural reliance on sound and the persistent nature of anthropogenic noise, especially in the wild. Industrial, commercial, and recreational human activity has expanded across the seas, resulting in a propagation of sound with varying frequency characteristics. In many countries, current regulations are based on the potential to induce hearing loss; however, a more nuanced approach is needed when shaping regulations, due to other non-hearing loss effects including activation of the stress response, acoustic masking, frequency shifts, alterations in behavior, and decreased foraging. Cetaceans in managedcare settings share the …


Low Light Intensity Delays Vegetative Phase Change, Mingli Xu, Tieqiang Hu, R Scott Poethig Nov 2021

Low Light Intensity Delays Vegetative Phase Change, Mingli Xu, Tieqiang Hu, R Scott Poethig

Faculty Publications

Plants that develop under low light (LL) intensity often display a phenotype known as the “shade tolerance syndrome (STS)”. This syndrome is similar to the phenotype of plants in the juvenile phase of shoot development, but the basis for this similarity is unknown. We tested the hypothesis that the STS is regulated by the same mechanism that regulates the juvenile vegetative phase by examining the effect of LL on rosette development in Arabidopsis (Arabidopsis thaliana). We found that LL prolonged the juvenile vegetative phase and that this was associated with an increase in the expression of the master …


The Ghost Of Hosts Past: Impacts Of Host Extinction On Parasite Specificity, Maxwell J. Farrell, Andrew W. Park, Clayton E. Cressler, Tad Dallas, Shan Huang, Nicole Mideo, Ignacio Morales-Castilla, T. Jonathan Davies, Patrick Stephens Sep 2021

The Ghost Of Hosts Past: Impacts Of Host Extinction On Parasite Specificity, Maxwell J. Farrell, Andrew W. Park, Clayton E. Cressler, Tad Dallas, Shan Huang, Nicole Mideo, Ignacio Morales-Castilla, T. Jonathan Davies, Patrick Stephens

Faculty Publications

A growing body of research is focused on the extinction of parasite species in response to host endangerment and declines. Beyond the loss of parasite species richness, host extinction can impact apparent parasite host specificity, as measured by host richness or the phylogenetic distances among hosts. Such impacts on the distribution of parasites across the host phylogeny can have knock-on effects that may reshape the adaptation of both hosts and parasites, ultimately shifting the evolutionary landscape underlying the potential for emergence and the evolution of virulence across hosts. Here, we examine how the reshaping of host phylogenies through extinction may …


The Future Of Zoonotic Risk Prediction, Colin J. Carlson, Maxwell J. Farrell, Zoe Grange, Barbara A. Han, Nardus Mollentze, Alexandra L. Phelan, Angela L. Rasmussen, Gregory F. Albery, Bernard Bett, David M. Brett-Major, Lily E. Cohen, Tad Dallas, Evan A. Eskew, Anna C. Fagre, Kristian M. Forbes, Rory Gibb, Sam Halabi, Charlotte C. Hammer, Rebecca Katz, Jason Kindrachuk, Renata L. Muylaert, Felicia B. Nutter, Joseph Ogola, Kevin J. Olival, Michelle Rourke, Sadie J. Ryan, Noam Ross, Stephanie N. Seifert, Tarja Sironen, Claire J. Standley, Kishana Taylor, Marietjie Venter, Paul W. Webala Sep 2021

The Future Of Zoonotic Risk Prediction, Colin J. Carlson, Maxwell J. Farrell, Zoe Grange, Barbara A. Han, Nardus Mollentze, Alexandra L. Phelan, Angela L. Rasmussen, Gregory F. Albery, Bernard Bett, David M. Brett-Major, Lily E. Cohen, Tad Dallas, Evan A. Eskew, Anna C. Fagre, Kristian M. Forbes, Rory Gibb, Sam Halabi, Charlotte C. Hammer, Rebecca Katz, Jason Kindrachuk, Renata L. Muylaert, Felicia B. Nutter, Joseph Ogola, Kevin J. Olival, Michelle Rourke, Sadie J. Ryan, Noam Ross, Stephanie N. Seifert, Tarja Sironen, Claire J. Standley, Kishana Taylor, Marietjie Venter, Paul W. Webala

Faculty Publications

In the light of the urgency raised by the COVID-19 pandemic, global investment in wildlife virology is likely to increase, and new surveillance programmes will identify hundreds of novel viruses that might someday pose a threat to humans. To support the extensive task of laboratory characterization, scientists may increasingly rely on data-driven rubrics or machine learning models that learn from known zoonoses to identify which animal pathogens could someday pose a threat to global health. We synthesize the findings of an interdisciplinary workshop on zoonotic risk technologies to answer the following questions. What are the prerequisites, in terms of open …


The Ghost Of Hosts Past: Impacts Of Host Extinction On Parasite Specificity, Maxwell J. Farrell, Andrew W. Park, Clayton E. Cressler, Tad Dallas, Shan Huang, Nicole Mideo, Ignacio Morales-Castilla, T. Jonathan Davies, Patrick Stephens Sep 2021

The Ghost Of Hosts Past: Impacts Of Host Extinction On Parasite Specificity, Maxwell J. Farrell, Andrew W. Park, Clayton E. Cressler, Tad Dallas, Shan Huang, Nicole Mideo, Ignacio Morales-Castilla, T. Jonathan Davies, Patrick Stephens

Faculty Publications

A growing body of research is focused on the extinction of parasite species in response to host endangerment and declines. Beyond the loss of parasite species richness, host extinction can impact apparent parasite host specificity, as measured by host richness or the phylogenetic distances among hosts. Such impacts on the distribution of parasites across the host phylogeny can have knock-on effects that may reshape the adaptation of both hosts and parasites, ultimately shifting the evolutionary landscape underlying the potential for emergence and the evolution of virulence across hosts. Here, we examine how the reshaping of host phylogenies through extinction may …


Local Translation Across Neural Development: A Focus On Radial Glial Cells, Axons, And Synaptogenesis, Manasu Agrawal, Kristy Welshhans Aug 2021

Local Translation Across Neural Development: A Focus On Radial Glial Cells, Axons, And Synaptogenesis, Manasu Agrawal, Kristy Welshhans

Faculty Publications

In the past two decades, significant progress has been made in our understanding of mRNA localization and translation at distal sites in axons and dendrites. The existing literature shows that local translation is regulated in a temporally and spatially restricted manner and is critical throughout embryonic and post-embryonic life. Here, recent key findings about mRNA localization and local translation across the various stages of neural development, including neurogenesis, axon development, and synaptogenesis, are reviewed. In the early stages of development, mRNAs are localized and locally translated in the endfeet of radial glial cells, but much is still unexplored about their …


Mitochondrial Genome Of Geomydoecus Aurei, A Pocket-Gopher Louse, Theresa A. Spradling, Alexandra C. Place, Ashley L. Campbell, James W. Demastes Jul 2021

Mitochondrial Genome Of Geomydoecus Aurei, A Pocket-Gopher Louse, Theresa A. Spradling, Alexandra C. Place, Ashley L. Campbell, James W. Demastes

Faculty Publications

Parasitic lice demonstrate an unusual array of mitochondrial genome architectures and gene arrangements. We characterized the mitochondrial genome of Geomydoecus aurei, a chewing louse (Phthiraptera: Trichodectidae) found on pocket gophers (Rodentia: Geomyidae) using reads from both Illumina and Oxford Nanopore sequencing coupled with PCR, cloning, and Sanger sequencing to verify structure and arrangement for each chromosome. The genome consisted of 12 circular mitochondrial chromosomes ranging in size from 1,318 to 2,088 nucleotides (nt). Total genome size was 19,015 nt. All 37 genes typical of metazoans (2 rRNA genes, 22 tRNA genes, and 13 protein-coding genes) were present. An average …


Individual Quality And Phenology Mediate The Effect Of Radioactive Contamination On Body Temperature In Chernobyl Barn Swallows, Zbyszek Boratynski, Timothy A. Mousseau, Anders Pape Moller Jul 2021

Individual Quality And Phenology Mediate The Effect Of Radioactive Contamination On Body Temperature In Chernobyl Barn Swallows, Zbyszek Boratynski, Timothy A. Mousseau, Anders Pape Moller

Faculty Publications

Anthropogenic stressors, such as radioactive contaminants released from the Chernobyl and Fukushima Daiichi accidents, deteriorate ecological and evolutionary processes, as evidence for damaging effects of radioactive contamination on wildlife is accumulating. Yet little is known about physiological traits of animals inhabiting contaminated areas, and how those are affected by individual quality and phenology. We investigated variation in body temperature of wild barn swallows, Hirundo rustica, exposed to radioactive contamination from the Chernobyl accident in Ukraine and Belarus. We tested whether exposure to variable levels of radioactive contamination modified core body temperature of birds, and whether individual and phenological characteristics modulated …


The Impact Of Aquaculture On The Genetics And Distribution Of The Onuphid Annelid Diopatra Biscayensis, Matthew P. Galaska, David S. Wethey, Andres Arias, Stanislas F. Dubois, Kenneth M. Halanych, Sarah A. Woodin Jun 2021

The Impact Of Aquaculture On The Genetics And Distribution Of The Onuphid Annelid Diopatra Biscayensis, Matthew P. Galaska, David S. Wethey, Andres Arias, Stanislas F. Dubois, Kenneth M. Halanych, Sarah A. Woodin

Faculty Publications

Aim

Evolutionary history of natural populations can be confounded by human intervention such as the case of decorator worm species Diopatra (Onuphidae), which have a history of being transported through anthropogenic activities. Because they build tubes and act as ecosystem engineers, they can have a large impact on the overall ecosystem in which they occur. One conspicuous member, Diopatra biscayensis, which was only described in 2012, has a fragmented distribution that includes the Bay of Biscay and the Normanno-Breton Gulf in the English Channel. This study explores the origin of these worms in the Normanno-Breton region, which has been …


Genomic Gc Content Drifts Downward In Most Bacterial Genomes, Ely Bert May 2021

Genomic Gc Content Drifts Downward In Most Bacterial Genomes, Ely Bert

Faculty Publications

In every kingdom of life, GC->AT transitions occur more frequently than any other type of mutation due to the spontaneous deamination of cytidine. In eukaryotic genomes, this slow loss of GC base pairs is counteracted by biased gene conversion which increases genomic GC content as part of the recombination process. However, this type of biased gene conversion has not been observed in bacterial genomes, so we hypothesized that GC->AT transitions cause a reduction of genomic GC content in prokaryotic genomes on an evolutionary time scale. To test this hypothesis, we used a phylogenetic approach to analyze triplets of …


The Impact Of Aquaculture On The Genetics And Distribution Of The Onuphid Annelid Diopatra Biscayensis, Matthew P. Galaska, David S. Wethey, Andrés Arias, Stanislas F. Dubois, Kenneth M. Halanych, Sarah A. Woodin May 2021

The Impact Of Aquaculture On The Genetics And Distribution Of The Onuphid Annelid Diopatra Biscayensis, Matthew P. Galaska, David S. Wethey, Andrés Arias, Stanislas F. Dubois, Kenneth M. Halanych, Sarah A. Woodin

Faculty Publications

Aim

Evolutionary history of natural populations can be confounded by human intervention such as the case of decorator worm species Diopatra (Onuphidae), which have a history of being transported through anthropogenic activities. Because they build tubes and act as ecosystem engineers, they can have a large impact on the overall ecosystem in which they occur. One conspicuous member, Diopatra biscayensis, which was only described in 2012, has a fragmented distribution that includes the Bay of Biscay and the Normanno-Breton Gulf in the English Channel. This study explores the origin of these worms in the Normanno-Breton region, which has been …


Comparable Response Of Wild Rodent Gut Microbiome To Anthropogenic Habitat Contamination, Anton Lavrinienko, Ann Hämäläinen, Rasmus Hindstrom, Eugene Tukalenko, Zbyszek Boratynski, Kati Kivisaari, Timothy Mousseau, Phillip C. Watts, Tapio Mappes Apr 2021

Comparable Response Of Wild Rodent Gut Microbiome To Anthropogenic Habitat Contamination, Anton Lavrinienko, Ann Hämäläinen, Rasmus Hindstrom, Eugene Tukalenko, Zbyszek Boratynski, Kati Kivisaari, Timothy Mousseau, Phillip C. Watts, Tapio Mappes

Faculty Publications

Species identity is thought to dominate over environment in shaping wild rodent gut microbiota, but it remains unknown whether the responses of host gut microbiota to shared anthropogenic habitat impacts are species-specific or if the general gut microbiota response is similar across host species. Here, we compare the influence of exposure to radionuclide contamination on the gut microbiota of four wild mouse species: Apodemus flavicollis, A. sylvaticus, A. speciosus and A. argenteus. Building on the evidence that radiation impacts bank vole (Myodes glareolus) gut microbiota, we hypothesized that radiation exposure has a general impact on rodent gut microbiota. Because we …


The Malina Oceanographic Expedition: How Do Changes In Ice Cover, Permafrost And Uv Radiation Impact Biodiversity And Biogeochemical Fluxes In The Arctic Ocean?, Philippe Massicotte, Rainer M.W. Amon, Antoine David, Sergio Balzano, Simon Bélanger, Ronald Benner, Dominique Boeuf, Annick Bricaud, Flavienne Bruyant, Gwenaëlle Chaillou, Malik Chami, Bruno Charrière, Jing Chen, Hervé Claustre, Pierre Coupel, Nicole Delsaut, David Doxaran, Jens Ehn, Cédric Fichot, Marie-Hélène Forget, Et. Al. Apr 2021

The Malina Oceanographic Expedition: How Do Changes In Ice Cover, Permafrost And Uv Radiation Impact Biodiversity And Biogeochemical Fluxes In The Arctic Ocean?, Philippe Massicotte, Rainer M.W. Amon, Antoine David, Sergio Balzano, Simon Bélanger, Ronald Benner, Dominique Boeuf, Annick Bricaud, Flavienne Bruyant, Gwenaëlle Chaillou, Malik Chami, Bruno Charrière, Jing Chen, Hervé Claustre, Pierre Coupel, Nicole Delsaut, David Doxaran, Jens Ehn, Cédric Fichot, Marie-Hélène Forget, Et. Al.

Faculty Publications

The MALINA oceanographic campaign was conducted during summer 2009 to investigate the carbon stocks and the processes controlling the carbon fluxes in the Mackenzie River estuary and the Beaufort Sea. During the campaign, an extensive suite of physical, chemical and biological variables were measured across seven shelf-basin transects (south-north) to capture the meridional gradient between the estuary and the open ocean. Key variables such as temperature, absolute salinity, radiance, irradiance, nutrient concentrations, chlorophyll a concentration, bacteria, phytoplankton and zooplankton abundance and taxonomy, and carbon stocks and fluxes were routinely measured onboard the Canadian research icebreaker CCGS Amundsen and from a …


What Is Refractory Organic Matter In The Ocean?, Federico Baltar, Xosé A. Alvarez-Salgado, Javier Arístegui, Ronald Benner, Dennis A. Hansell, Gerhard J. Herndl, Christian Lønborg Apr 2021

What Is Refractory Organic Matter In The Ocean?, Federico Baltar, Xosé A. Alvarez-Salgado, Javier Arístegui, Ronald Benner, Dennis A. Hansell, Gerhard J. Herndl, Christian Lønborg

Faculty Publications

About 20% of the organic carbon produced in the sunlit surface ocean is transported into the ocean’s interior as dissolved, suspended and sinking particles to be mineralized and sequestered as dissolved inorganic carbon (DIC), sedimentary particulate organic carbon (POC) or “refractory” dissolved organic carbon (rDOC). Recently, the physical and biological mechanisms associated with the particle pumps have been revisited, suggesting that accepted fluxes might be severely underestimated (Boyd et al., 2019; Buesseler et al., 2020). Perhaps even more poorly understood are the mechanisms driving rDOC production and its potential accumulation in the ocean. On the basis of …


Activating Mutations In Braf Disrupt The Hypothalamo-Pituitary Axis Leading To Hypopituitarism In Mice And Humans, Angelica Gualtieri, Nikolina Kyprianou, Louise C. Gregory, Maria Lillina Vignola, James G. Nicholson, Rachael Tan, Shin-Ichi Inoue, Valeria Scagliotti, Pedro Casado, James Blackburn, Fernando Abollo-Jimenez, Eugenia Marinelli, Rachael E.J. Besser, Wolfgang Högler, I. Karen Temple, Justin H. Davies, Andrey Gagunashvili, Iain C.A.F. Robinson, Sally A. Camper, Shannon W. Davis, Pedro R. Cutillas, Evelien F. Gevers, Yoko Aoki, Mehul T. Dattani, Carles Gaston-Massuet Apr 2021

Activating Mutations In Braf Disrupt The Hypothalamo-Pituitary Axis Leading To Hypopituitarism In Mice And Humans, Angelica Gualtieri, Nikolina Kyprianou, Louise C. Gregory, Maria Lillina Vignola, James G. Nicholson, Rachael Tan, Shin-Ichi Inoue, Valeria Scagliotti, Pedro Casado, James Blackburn, Fernando Abollo-Jimenez, Eugenia Marinelli, Rachael E.J. Besser, Wolfgang Högler, I. Karen Temple, Justin H. Davies, Andrey Gagunashvili, Iain C.A.F. Robinson, Sally A. Camper, Shannon W. Davis, Pedro R. Cutillas, Evelien F. Gevers, Yoko Aoki, Mehul T. Dattani, Carles Gaston-Massuet

Faculty Publications

Germline mutations in BRAF and other components of the MAPK pathway are associated with the congenital syndromes collectively known as RASopathies. Here, we report the association of Septo-Optic Dysplasia (SOD) including hypopituitarism and Cardio-Facio-Cutaneous (CFC) syndrome in patients harbouring mutations in BRAF. Phosphoproteomic analyses demonstrate that these genetic variants are gain-of-function mutations leading to activation of the MAPK pathway. Activation of the MAPK pathway by conditional expression of the BrafV600E/+ allele, or the knock-in BrafQ241R/+ allele (corresponding to the most frequent human CFC-causing mutation, BRAF p.Q257R), leads to abnormal cell lineage determination and terminal differentiation of …


Genes Related To Redox And Cell Curvature Facilitate Interactions Between Caulobacter Strains And Arabidopsis, Louis Berrios, Bert Ely Apr 2021

Genes Related To Redox And Cell Curvature Facilitate Interactions Between Caulobacter Strains And Arabidopsis, Louis Berrios, Bert Ely

Faculty Publications

Bacteria play an integral role in shaping plant growth and development. However, the genetic factors that facilitate plant-bacteria interactions remain largely unknown. Here, we demonstrated the importance of two bacterial genetic factors that facilitate the interactions between plant-growth-promoting (PGP) bacteria in the genus Caulobacter and the host plant Arabidopsis. Using homologous recombination, we disrupted the cytochrome ubiquinol oxidase (cyo) operon in both C. vibrioides CB13 and C. segnis TK0059 by knocking out the expression of cyoB (critical subunit of the cyo operon) and showed that the mutant strains were unable to enhance the growth of …


What Is Refractory Organic Matter In The Ocean?, Federico Baltar, Xosé A. Alvarez-Salgado, Javier Arístegui, Ronald Benner, Dennis A. Hansell, Gerhard J. Herndl, Christian Lønborg Apr 2021

What Is Refractory Organic Matter In The Ocean?, Federico Baltar, Xosé A. Alvarez-Salgado, Javier Arístegui, Ronald Benner, Dennis A. Hansell, Gerhard J. Herndl, Christian Lønborg

Faculty Publications

About 20% of the organic carbon produced in the sunlit surface ocean is transported into the ocean’s interior as dissolved, suspended and sinking particles to be mineralized and sequestered as dissolved inorganic carbon (DIC), sedimentary particulate organic carbon (POC) or “refractory” dissolved organic carbon (rDOC). Recently, the physical and biological mechanisms associated with the particle pumps have been revisited, suggesting that accepted fluxes might be severely underestimated (Boyd et al., 2019; Buesseler et al., 2020). Perhaps even more poorly understood are the mechanisms driving rDOC production and its potential accumulation in the ocean. On the basis of …


What Is Refractory Organic Matter In The Ocean?, Federico Baltar, Xosé A. Alvarez-Salgado, Javier Arístegui, Ronald Benner, Dennis A. Hansell, Gerhard J. Herndl, Christian Lønborg Apr 2021

What Is Refractory Organic Matter In The Ocean?, Federico Baltar, Xosé A. Alvarez-Salgado, Javier Arístegui, Ronald Benner, Dennis A. Hansell, Gerhard J. Herndl, Christian Lønborg

Faculty Publications

About 20% of the organic carbon produced in the sunlit surface ocean is transported into the ocean’s interior as dissolved, suspended and sinking particles to be mineralized and sequestered as dissolved inorganic carbon (DIC), sedimentary particulate organic carbon (POC) or “refractory” dissolved organic carbon (rDOC). Recently, the physical and biological mechanisms associated with the particle pumps have been revisited, suggesting that accepted fluxes might be severely underestimated (Boyd et al., 2019; Buesseler et al., 2020). Perhaps even more poorly understood are the mechanisms driving rDOC production and its potential accumulation in the ocean. On the basis of …


Protocols For Assessing Transformation Rates Of Nitrous Oxide In The Water Column, Annie Bourbonnais, Claudia Frey, Xin Sun, Laura A. Bristow, Amal Jayakumar, Nathaniel E. Ostrom, Karen L. Casciotti, Bess B. Ward Apr 2021

Protocols For Assessing Transformation Rates Of Nitrous Oxide In The Water Column, Annie Bourbonnais, Claudia Frey, Xin Sun, Laura A. Bristow, Amal Jayakumar, Nathaniel E. Ostrom, Karen L. Casciotti, Bess B. Ward

Faculty Publications

Nitrous oxide (N2O) is a potent greenhouse gas and an ozone destroying substance. Yet, clear step-by-step protocols to measure N2O transformation rates in freshwater and marine environments are still lacking, challenging inter-comparability efforts. Here we present detailed protocols currently used by leading experts in the field to measure water-column N2O production and consumption rates in both marine and other aquatic environments. We present example 15N-tracer incubation experiments in marine environments as well as templates to calculate both N2O production and consumption rates. We discuss important considerations and recommendations regarding (1) precautions to prevent oxygen (O2) contamination during low-oxygen and anoxic …


Diversity And N2o Production Potential Of Fungi In An Oceanic Oxygen Minimum Zone, Xuefeng Peng, David L. Valentine Mar 2021

Diversity And N2o Production Potential Of Fungi In An Oceanic Oxygen Minimum Zone, Xuefeng Peng, David L. Valentine

Faculty Publications

Fungi in terrestrial environments are known to play a key role in carbon and nitrogen biogeochemistry and exhibit high diversity. In contrast, the diversity and function of fungi in the ocean has remained underexplored and largely neglected. In the eastern tropical North Pacific oxygen minimum zone, we examined the fungal diversity by sequencing the internal transcribed spacer region 2 (ITS2) and mining a metagenome dataset collected from the same region. Additionally, we coupled 15N-tracer experiments with a selective inhibition method to determine the potential contribution of marine fungi to nitrous oxide (N2O) production. Fungal communities evaluated by …


Biophysical Characteristics Of Lipid-Induced Aβ Oligomers Correlate To Distinctive Phenotypes In Transgenic Mice, Jhinuk Saha, Dexter N. Dean, Shailendra Dhakal, Kelli A. Stockmal, Sarah E. Morgan, Kristy D. Dillon, Munir F. Adamo, Yona Levites, Vijayaraghavan Rangachari Feb 2021

Biophysical Characteristics Of Lipid-Induced Aβ Oligomers Correlate To Distinctive Phenotypes In Transgenic Mice, Jhinuk Saha, Dexter N. Dean, Shailendra Dhakal, Kelli A. Stockmal, Sarah E. Morgan, Kristy D. Dillon, Munir F. Adamo, Yona Levites, Vijayaraghavan Rangachari

Faculty Publications

Alzheimer's disease (AD) is a progressive neurodegenerative disorder that affects cognition and memory. Recent advances have helped identify many clinical sub-types in AD. Mounting evidence point toward structural polymorphism among fibrillar aggregates of amyloid-β (Aβ) to being responsible for the phenotypes and clinical manifestations. In the emerging paradigm of polymorphism and prion-like propagation of aggregates in AD, the role of low molecular weight soluble oligomers, which are long known to be the primary toxic agents, in effecting phenotypes remains inconspicuous. In this study, we present the characterization of three soluble oligomers of Aβ42, namely 14LPOs, 16LPOs, and GM1Os with discreet …


Propranolol Sensitizes Vascular Sarcoma Cells To Doxorubicin By Altering Lysosomal Drug Sequestration And Drug Efflux, Jhuma Saha, Jong Hyuk Kim, Clarissa N. Amaya, Caleb M. Witcher, Ali Khammanivong, Derek M. Korpela, David R. Brown, Josephine Taylor, Brad A. Bryan, Erin B. Dickerson Jan 2021

Propranolol Sensitizes Vascular Sarcoma Cells To Doxorubicin By Altering Lysosomal Drug Sequestration And Drug Efflux, Jhuma Saha, Jong Hyuk Kim, Clarissa N. Amaya, Caleb M. Witcher, Ali Khammanivong, Derek M. Korpela, David R. Brown, Josephine Taylor, Brad A. Bryan, Erin B. Dickerson

Faculty Publications

Angiosarcoma is a rare cancer of blood vessel–forming cells with a high patient mortality and few treatment options. Although chemotherapy often produces initial clinical responses, outcomes remain poor, largely due to the development of drug resistance. We previously identified a subset of doxorubicin-resistant cells in human angiosarcoma and canine hemangiosarcoma cell lines that exhibit high lysosomal accumulation of doxorubicin. Hydrophobic, weak base chemotherapeutics, like doxorubicin, are known to sequester within lysosomes, promoting resistance by limiting drug accessibility to cellular targets. Drug synergy between the beta adrenergic receptor (β-AR) antagonist, propranolol, and multiple chemotherapeutics has been documented in vitro, and …


Effects Of Body Temperature On Initial Bite Force In Three Species Of Rock- And Crevice-Dwelling Lizards From Mexico, Guillermo A. Woolrich-Piña, Geoffrey R. Smith, Norberto Martínez-Méndez, Julio A. Lemos-Espinal, Héctor Gadsden-Esparz Jan 2021

Effects Of Body Temperature On Initial Bite Force In Three Species Of Rock- And Crevice-Dwelling Lizards From Mexico, Guillermo A. Woolrich-Piña, Geoffrey R. Smith, Norberto Martínez-Méndez, Julio A. Lemos-Espinal, Héctor Gadsden-Esparz

Faculty Publications

No abstract provided.


The Iron-Responsive Genome Of The Chiton Acanthopleura Granulata, Rebecca M. Varney, Daniel Isaac Speiser, Carmel Mcdougall, Bernard M. Degnan, Kevin M. Kocot Jan 2021

The Iron-Responsive Genome Of The Chiton Acanthopleura Granulata, Rebecca M. Varney, Daniel Isaac Speiser, Carmel Mcdougall, Bernard M. Degnan, Kevin M. Kocot

Faculty Publications

Molluscs biomineralize structures that vary in composition, form, and function, prompting questions about the genetic mechanisms responsible for their production and the evolution of these mechanisms. Chitons (Mollusca, Polyplacophora) are a promising system for studies of biomineralization because they build a range of calcified structures including shell plates and spine- or scale-like sclerites. Chitons also harden the calcified teeth of their rasp-like radula with a coat of iron (as magnetite). Here we present the genome of the West Indian fuzzy chiton Acanthopleura granulata, the first from any aculiferan mollusc. The A. granulata genome contains homologs of many genes associated …


Juvenile Leaves Or Adult Leaves: Determinants For Vegetative Phase Change In Flowering Plants, Darren Manuela, Mingli Xu Dec 2020

Juvenile Leaves Or Adult Leaves: Determinants For Vegetative Phase Change In Flowering Plants, Darren Manuela, Mingli Xu

Faculty Publications

Vegetative leaves in Arabidopsis are classified as either juvenile leaves or adult leaves based on their specific traits, such as leaf shape and the presence of abaxial trichomes. The timing of the juvenile-to-adult phase transition during vegetative development, called the vegetative phase change, is a critical decision for plants, as this transition is associated with crop yield, stress responses, and immune responses. Juvenile leaves are characterized by high levels of miR156/157, and adult leaves are characterized by high levels of miR156/157 targets, SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors. The discovery of this miR156/157-SPL module provided a critical tool for …


Associative Nitrogen Fixation Linked With Three Perennial Bioenergy Grasses In Field And Greenhouse Experiments, Jayani J. Wewalwela, Yuan Tian, Janet R. Donaldson, Brian S. Baldwin, Jac J. Varco, Brett Rushing, Haoliang Lu, Mark A. Williams Dec 2020

Associative Nitrogen Fixation Linked With Three Perennial Bioenergy Grasses In Field And Greenhouse Experiments, Jayani J. Wewalwela, Yuan Tian, Janet R. Donaldson, Brian S. Baldwin, Jac J. Varco, Brett Rushing, Haoliang Lu, Mark A. Williams

Faculty Publications

© 2020 The Authors. Associative nitrogen (N2)‐fixation (ANF) by bacteria in the root‐zone of perennial bioenergy grasses has the potential to replace or supplement N fertilizer and support sustainable production of biomass, but its application in marginal ecosystems requires further evaluation. In this study, we first combined both greenhouse and field experiments, to explore the N2 fixation effects of three temperate feedstocks Miscanthus × giganteus (giant miscanthus, Freedom), Panicum virgatum (switchgrass, Alamo), and Saccharum sp. (energycane, Ho 02‐147). In field studies across three growing seasons, plant and soil pools of candidate feedstocks were partially composed of N …