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Full-Text Articles in Life Sciences

A Single Vertebrate Dna Virus Protein Disarms Invertebrate Immunity To Rna Virus Infection, Don B. Gammon, Sophie Duraffour, Daniel K. Rozelle, Heidi Hehnly, Rita Sharma, Michael E. Sparks, Cara C. West, Ying Chen, James J. Moresco, Graciela Andrei, John H. Connor, Darryl Conte Jr., Dawn E. Gundersen-Rindal, William L. Marshall, John R. Yates, Neal S. Silverman, Craig C. Mello Dec 2014

A Single Vertebrate Dna Virus Protein Disarms Invertebrate Immunity To Rna Virus Infection, Don B. Gammon, Sophie Duraffour, Daniel K. Rozelle, Heidi Hehnly, Rita Sharma, Michael E. Sparks, Cara C. West, Ying Chen, James J. Moresco, Graciela Andrei, John H. Connor, Darryl Conte Jr., Dawn E. Gundersen-Rindal, William L. Marshall, John R. Yates, Neal S. Silverman, Craig C. Mello

Neal Silverman

Virus-host interactions drive a remarkable diversity of immune responses and countermeasures. We found that two RNA viruses with broad host ranges, vesicular stomatitis virus (VSV) and Sindbis virus (SINV), are completely restricted in their replication after entry into Lepidopteran cells. This restriction is overcome when cells are co-infected with vaccinia virus (VACV), a vertebrate DNA virus. Using RNAi screening, we show that Lepidopteran RNAi, Nuclear Factor-kappaB, and ubiquitin-proteasome pathways restrict RNA virus infection. Surprisingly, a highly conserved, uncharacterized VACV protein, A51R, can partially overcome this virus restriction. We show that A51R is also critical for VACV replication in vertebrate cells …


Transcriptomic And Proteomic Dynamics In The Metabolism Of A Diazotrophic Cyanobacterium, Cyanothece Sp. Pcc 7822 During A Diurnal Light-Dark Cycle, Louis Sherman Dec 2014

Transcriptomic And Proteomic Dynamics In The Metabolism Of A Diazotrophic Cyanobacterium, Cyanothece Sp. Pcc 7822 During A Diurnal Light-Dark Cycle, Louis Sherman

Louis A Sherman

Background: Cyanothece sp. PCC 7822 is an excellent cyanobacterial model organism with great potential to be applied as a biocatalyst for the production of high value compounds. Like other unicellular diazotrophic cyanobacterial species, it has a tightly regulated metabolism synchronized to the light-dark cycle. Utilizing transcriptomic and proteomic methods, we were able to quantify the relationships between transcription and translation underlying central and secondary metabolism in response to nitrogen free, 12 hour light and 12 hour dark conditions.

Results: By combining mass-spectrometry based proteomics and RNA-sequencing transcriptomics, we quantitatively measured a total of 6766 mRNAs and 1322 proteins at four …


Chlorovirus Atcv-1 Is Part Of The Human Oropharyngeal Virome And Is Associated With Changes In Cognitive Functions In Humans And Mice, Lorraine Jones-Brando Ph. D., Robert H. Yolken M. D., David D. Dunigan Ph. D. Oct 2014

Chlorovirus Atcv-1 Is Part Of The Human Oropharyngeal Virome And Is Associated With Changes In Cognitive Functions In Humans And Mice, Lorraine Jones-Brando Ph. D., Robert H. Yolken M. D., David D. Dunigan Ph. D.

David D Dunigan Ph. D.

Chloroviruses (family Phycodnaviridae) are large DNA viruses known to infect certain eukaryotic green algae and have not been previously shown to infect humans or to be part of the human virome. We unexpectedly found sequences homologous to the chlorovirus Acanthocystis turfacea chlorella virus 1 (ATCV-1) in a metagenomic analysis of DNA extracted from human oropharyngeal samples. These samples were obtained by throat swabs of adults without a psychiatric disorder or serious physical illness who were participating in a study that included measures of cognitive functioning. The presence of ATCV-1 DNA was confirmed by quantitative PCR with ATCV-1 DNA being documented …


Tal Effector-Nucleotide Targeter (Tale-Nt) 2.0: Tools For Tal Effector Design And Target Prediction, Erin L. Doyle, Nicholas J. Booher, Daniel S. Standage, Daniel F. Voytas, Volker P. Brendel, John K. Vandyk, Adam J. Bogdanove Oct 2014

Tal Effector-Nucleotide Targeter (Tale-Nt) 2.0: Tools For Tal Effector Design And Target Prediction, Erin L. Doyle, Nicholas J. Booher, Daniel S. Standage, Daniel F. Voytas, Volker P. Brendel, John K. Vandyk, Adam J. Bogdanove

John K. VanDyk

Transcription activator-like (TAL) effectors are repeat-containing proteins used by plant pathogenic bacteria to manipulate host gene expression. Repeats are polymorphic and individually specify single nucleotides in the DNA target, with some degeneracy. A TAL effector-nucleotide binding code that links repeat type to specified nucleotide enables prediction of genomic binding sites for TAL effectors and customization of TAL effectors for use in DNA targeting, in particular as custom transcription factors for engineered gene regulation and as site-specific nucleases for genome editing. We have developed a suite of web-based tools called TAL Effector-Nucleotide Targeter 2.0 (TALE-NT 2.0;https://boglab.plp.iastate.edu/) that enables design of custom …


Herbert W. Conn: Formative Decades Of Microbiology And Evolutionary Biology, Frederick M. Cohan, Alexa Boesel Sep 2014

Herbert W. Conn: Formative Decades Of Microbiology And Evolutionary Biology, Frederick M. Cohan, Alexa Boesel

Frederick M. Cohan

Herbert W. Conn (1859–1917) made outstanding contributions to both microbiology and evolutionary biology, reflecting his intellectual command of several biological disciplines. Conn endeavored to make the unseen world of microbes familiar, real, and consequential to members of the general public. He presciently considered the role of bacteria in our own bodies, describing them as being both harmful and beneficial to our health. He also contributed to our understanding of the concept of species, how they originate, and what those ideas might mean in terms of bacterial speciation. In Conn’s spirit, microbial ecologists studying speciation eschew the “species” taxa of bacterial …


Dengue Viral Rna Levels In Peripheral Blood Mononuclear Cells Are Associated With Disease Severity And Preexisting Dengue Immune Status, Anon Srikiatkhachorn, Sineewanlaya Wichit, Robert V. Gibbons, Sharone Green, Daniel H. Libraty, Timothy P. Endy, Francis A. Ennis, Siripen Kalayanarooj, Alan L. Rothman Aug 2014

Dengue Viral Rna Levels In Peripheral Blood Mononuclear Cells Are Associated With Disease Severity And Preexisting Dengue Immune Status, Anon Srikiatkhachorn, Sineewanlaya Wichit, Robert V. Gibbons, Sharone Green, Daniel H. Libraty, Timothy P. Endy, Francis A. Ennis, Siripen Kalayanarooj, Alan L. Rothman

Alan Rothman

BACKGROUND: Infection with dengue viruses (DENV) causes a wide range of manifestations from asymptomatic infection to a febrile illness called dengue fever (DF), to dengue hemorrhagic fever (DHF). The in vivo targets of DENV and the relation between the viral burden in these cells and disease severity are not known.

METHOD: The levels of positive and negative strand viral RNA in peripheral blood monocytes, T/NK cells, and B cells and in plasma of DF and DHF cases were measured by quantitative RT-PCR.

RESULTS: Positive strand viral RNA was detected in monocytes, T/NK cells and B cells with the highest amounts …


National Park Service Cave Ecology Inventory And Monitoring Framework, Gretchen M. Baker, Steven J. Taylor, Shawn Thomas, Rick Olson, Kathy Lavoie, Marie Denn, Steven Thomas, Hazel Barton, Kurt Helf, Rene Ohms, Joel Despain, Jim Kennedy, David Larson May 2014

National Park Service Cave Ecology Inventory And Monitoring Framework, Gretchen M. Baker, Steven J. Taylor, Shawn Thomas, Rick Olson, Kathy Lavoie, Marie Denn, Steven Thomas, Hazel Barton, Kurt Helf, Rene Ohms, Joel Despain, Jim Kennedy, David Larson

Hazel Barton

A team developed the Cave Ecology Inventory and Monitoring Framework for National Park Service (NPS) units. It contains information for NPS cave managers across the United States to determine how to inventory and monitor cave ecology. Due to the wide geographical scope of NPS caves and their many different types, the document does not prescribe exact protocols. Instead, it provides guidance for what types of inventory and monitoring are possible, a framework for deciding how to prioritize inventory and monitoring activities, and references to specific protocols that are already in place at NPS cave parks. Keywords: cave ecology, cave microbiology, …


Evidence For Sigma Factor Competition In The Regulation Of Alginate Production By Pseudomonas Aeruginosa, Yeshi Yin, T. Ryan Withers, Xin Wang, Hongwei D. Yu Apr 2014

Evidence For Sigma Factor Competition In The Regulation Of Alginate Production By Pseudomonas Aeruginosa, Yeshi Yin, T. Ryan Withers, Xin Wang, Hongwei D. Yu

Hongwei Yu

Alginate overproduction, or mucoidy, plays an important role in the pathogenesis of P. aeruginosa lung infection in cystic fibrosis (CF). Mucoid strains with mucA mutations predominantly populate in chronically-infected patients. However, the mucoid strains can revert to nonmucoidy in vitro through suppressor mutations. We screened a mariner transposon library using CF149, a non-mucoid clinical isolate with a misssense mutation in algU(AlgUA61V). The wild type AlgU is a stress-related sigma factor that activates transcription of alginate biosynthesis. Three mucoid mutants were identified with transposon insertions that caused 1) an overexpression of AlgUA61V, 2) an overexpression of the stringent starvation protein A …


Dengue Viral Rna Levels In Peripheral Blood Mononuclear Cells Are Associated With Disease Severity And Preexisting Dengue Immune Status, Anon Srikiatkhachorn, Sineewanlaya Wichit, Robert V. Gibbons, Sharone Green, Daniel H. Libraty, Timothy P. Endy, Francis A. Ennis, Siripen Kalayanarooj, Alan L. Rothman Jan 2014

Dengue Viral Rna Levels In Peripheral Blood Mononuclear Cells Are Associated With Disease Severity And Preexisting Dengue Immune Status, Anon Srikiatkhachorn, Sineewanlaya Wichit, Robert V. Gibbons, Sharone Green, Daniel H. Libraty, Timothy P. Endy, Francis A. Ennis, Siripen Kalayanarooj, Alan L. Rothman

Sharone Green

BACKGROUND: Infection with dengue viruses (DENV) causes a wide range of manifestations from asymptomatic infection to a febrile illness called dengue fever (DF), to dengue hemorrhagic fever (DHF). The in vivo targets of DENV and the relation between the viral burden in these cells and disease severity are not known.

METHOD: The levels of positive and negative strand viral RNA in peripheral blood monocytes, T/NK cells, and B cells and in plasma of DF and DHF cases were measured by quantitative RT-PCR.

RESULTS: Positive strand viral RNA was detected in monocytes, T/NK cells and B cells with the highest amounts …


Microzooplankton Growth Rates Examined Across A Temperature Gradient In The Barents Sea, Gayantonia Franzè, Peter J. Lavrentyev Dec 2013

Microzooplankton Growth Rates Examined Across A Temperature Gradient In The Barents Sea, Gayantonia Franzè, Peter J. Lavrentyev

Peter J. Lavrentyev

Growth rates (µ) of abundant microzooplankton species were examined in field experiments conducted at ambient sea temperatures (21.8–9.0°C) in the Barents Sea and adjacent waters (70–78.5°N). The maximum species-specific m of ciliates and athecate dinoflagellates (0.33–1.67/d and 0.52–1.14/d, respectively) occurred at temperatures below 5°C and exceeded the µmax predicted by previously published, laboratory culture-derived equations. The opposite trend was found for thecate dinoflagellates, which grew faster in the warmer Atlantic Ocean water. Mixotrophic ciliates and dinoflagellates grew faster than their heterotrophic counterparts. At sub-zero temperatures, microzooplankton mmax matched those predicted for phytoplankton by temperature-dependent growth equations. These results indicate that …


Accuracy And Efficiency Of Algorithms For The Demarcation Of Bacterial Ecotypes From Dna Sequence Data, Juan Carlos Francisco, Frederick M. Cohan, Danny Krizanc Dec 2013

Accuracy And Efficiency Of Algorithms For The Demarcation Of Bacterial Ecotypes From Dna Sequence Data, Juan Carlos Francisco, Frederick M. Cohan, Danny Krizanc

Frederick M. Cohan

Identification of closely related, ecologically distinct populations of bacteria would benefit microbiologists working in many fields including systematics, epidemiology and biotechnology. Several laboratories have recently developed algorithms aimed at demarcating such ‘ecotypes’. We examine the ability of four of these algorithms to correctly identify ecotypes from sequence data. We tested the algorithms on synthetic sequences, with known history and habitat associations, generated under the stable ecotype model and on data from Bacillus strains isolated from Death Valley where previous work has confirmed the existence of multiple ecotypes. We found that one of the algorithms (ecotype simulation) performs significantly better than …


Microzooplankton Distribution, Dynamics, And Trophic Interactions Relative To Phytoplankton And Quagga Mussels In Saginaw Bay, Lake Huron, Peter J. Lavrentyev, Henry A. Vanderploeg, Gayantonia Franze, Dinorah H. Chacin, James R. Liebig, Thomas H. Johengen Dec 2013

Microzooplankton Distribution, Dynamics, And Trophic Interactions Relative To Phytoplankton And Quagga Mussels In Saginaw Bay, Lake Huron, Peter J. Lavrentyev, Henry A. Vanderploeg, Gayantonia Franze, Dinorah H. Chacin, James R. Liebig, Thomas H. Johengen

Peter J. Lavrentyev

Invasive quagga mussels have recently replaced zebra mussels as the dominant filter-feeding bivalves in the
Great Lakes. This study examined microzooplankton (i.e., grazers <200 μm) and their trophic interactions with
phytoplankton, bacteria, and bivalve mussels in Saginaw Bay, Lake Huron, following the zebra to quagga mussel
shift.Microzooplankton distribution displayed strong spatial and temporal variability (1.73–28.5 μg C/L) relative
to phytoplankton distribution. Ciliates were the dominant component, especially in the spring and early summer.
Rotifers and dinoflagellates increased toward late summer/fall in the inner and outer parts of the bay, respectively.
Microzooplankton grazing matched bacterial growth rates and removed ca. 30% …


Different Meal, Same Flavor: Cospeciation And Host Switching Of Haemosporidian Parasites In Some Non-Passerine Birds, Diego Santiago-Alarcon, Adriana Rodríguez-Ferraro, Patricia G. Parker, Robert E. Ricklefs Dec 2013

Different Meal, Same Flavor: Cospeciation And Host Switching Of Haemosporidian Parasites In Some Non-Passerine Birds, Diego Santiago-Alarcon, Adriana Rodríguez-Ferraro, Patricia G. Parker, Robert E. Ricklefs

Robert Ricklefs

Background
Previous studies have shown that haemosporidian parasites (Haemoproteus(Parahaemoproteus) and Plasmodium) infecting passerine birds have an evolutionary history of host switching with little cospeciation, in particular at low taxonomic levels (e.g., below the family level), which is suggested as the main speciation mechanism of this group of parasites. Recent studies have characterized diverse clades of haemosporidian parasites (H. (Haemoproteus) and H. (Parahaemoproteus)) infecting non-passerine birds (e.g., Columbiformes, Pelecaniiformes). Here, we explore the cospeciation history of H. (Haemoproteus) and H. (Parahaemoproteus) parasites with …


Different Meal, Same Flavor: Cospeciation And Host Switching Of Haemosporidian Parasites In Some Non-Passerine Birds, Diego Santiago-Alarcon, Adriana Rodríguez-Ferraro, Patricia G. Parker, Robert E. Ricklefs Dec 2013

Different Meal, Same Flavor: Cospeciation And Host Switching Of Haemosporidian Parasites In Some Non-Passerine Birds, Diego Santiago-Alarcon, Adriana Rodríguez-Ferraro, Patricia G. Parker, Robert E. Ricklefs

Patricia Parker

Background
Previous studies have shown that haemosporidian parasites (Haemoproteus (Parahaemoproteus) and Plasmodium) infecting passerine birds have an evolutionary history of host switching with little cospeciation, in particular at low taxonomic levels (e.g., below the family level), which is suggested as the main speciation mechanism of this group of parasites. Recent studies have characterized diverse clades of haemosporidian parasites (H. (Haemoproteus) and H. (Parahaemoproteus)) infecting non-passerine birds (e.g., Columbiformes, Pelecaniiformes). Here, we explore the cospeciation history of H. (Haemoproteus) and H. (Parahaemoproteus) parasites with their non-passerine hosts.

Methods
We sequenced the mtDNA cyt b gene of both haemosporidian parasites and their …


The Cryptococcus Neoformans Transcriptome At The Site Of Human Meningitis, Yuan Chen, Dena L. Toffaletti, Jennifer L. Tenor, Anastasia P. Litvintseva, Charles Fang, Thomas G. Mitchell, Tami R. Mcdonald, Kirsten Nielsen, David R. Boulware, Tihana Bicanic, John R. Perfect Dec 2013

The Cryptococcus Neoformans Transcriptome At The Site Of Human Meningitis, Yuan Chen, Dena L. Toffaletti, Jennifer L. Tenor, Anastasia P. Litvintseva, Charles Fang, Thomas G. Mitchell, Tami R. Mcdonald, Kirsten Nielsen, David R. Boulware, Tihana Bicanic, John R. Perfect

Tami McDonald

No abstract provided.