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Full-Text Articles in Life Sciences

Beryllium Nitrate Inhibits Fibroblast Migration To Disrupt Epimorphic Regeneration, Adam B. Cook, Ashley W. Seifert Oct 2016

Beryllium Nitrate Inhibits Fibroblast Migration To Disrupt Epimorphic Regeneration, Adam B. Cook, Ashley W. Seifert

Biology Faculty Publications

Epimorphic regeneration proceeds with or without formation of a blastema, as observed for the limb and skin, respectively. Inhibition of epimorphic regeneration provides a means to interrogate the cellular and molecular mechanisms that regulate it. In this study, we show that exposing amputated limbs to beryllium nitrate disrupts blastema formation and causes severe patterning defects in limb regeneration. In contrast, exposing full-thickness skin wounds to beryllium only causes a delay in skin regeneration. By transplanting full-thickness skin from ubiquitous GFP-expressing axolotls to wild-type hosts, we demonstrate that beryllium inhibits fibroblast migration during limb and skin regeneration in vivo. Moreover, …


Cellular And Molecular Features Of Developmentally Programmed Genome Rearrangement In A Vertebrate (Sea Lamprey: Petromyzon Marinus), Vladimir A. Timoshevskiy, Joseph R. Herdy, Melissa C. Keinath, Jeramiah J. Smith Jun 2016

Cellular And Molecular Features Of Developmentally Programmed Genome Rearrangement In A Vertebrate (Sea Lamprey: Petromyzon Marinus), Vladimir A. Timoshevskiy, Joseph R. Herdy, Melissa C. Keinath, Jeramiah J. Smith

Biology Faculty Publications

The sea lamprey (Petromyzon marinus) represents one of the few vertebrate species known to undergo large-scale programmatic elimination of genomic DNA over the course of its normal development. Programmed genome rearrangements (PGRs) result in the reproducible loss of ~20% of the genome from somatic cell lineages during early embryogenesis. Studies of PGR hold the potential to provide novel insights related to the maintenance of genome stability during the cell cycle and coordination between mechanisms responsible for the accurate distribution of chromosomes into daughter cells, yet little is known regarding the mechanistic basis or cellular context of PGR in …


Sine-Wave Electrical Stimulation Initiates A Voltage-Gated Potassium Channel-Dependent Soft Tissue Response Characterized By Induction Of Hemocyte Recruitment And Collagen Deposition, Brandon M. Franklin, Eleni Maroudas, Jeffrey L. Osborn Jun 2016

Sine-Wave Electrical Stimulation Initiates A Voltage-Gated Potassium Channel-Dependent Soft Tissue Response Characterized By Induction Of Hemocyte Recruitment And Collagen Deposition, Brandon M. Franklin, Eleni Maroudas, Jeffrey L. Osborn

Biology Faculty Publications

Soft tissue repair is a complex process that requires specific communication between multiple cell types to orchestrate effective restoration of physiological functions. Macrophages play a critical role in this wound healing process beginning at the onset of tissue injury. Understanding the signaling mechanisms involved in macrophage recruitment to the wound site is an essential step for developing more effective clinical therapies. Macrophages are known to respond to electrical fields, but the underlying cellular mechanisms mediating this response is unknown. This study demonstrated that low‐amplitude sine‐wave electrical stimulation (ES) initiates a soft tissue response in the absence of injury in Procambarus …


Changes In Oxidative Patterns During Dormancy Break By Warm And Cold Stratification In Seeds Of An Edible Fruit Tree, Dilinuer Shalimu, Jia Sun, Carol C. Baskin, Jerry M. Baskin, Liwei Sun, Yujun Liu May 2016

Changes In Oxidative Patterns During Dormancy Break By Warm And Cold Stratification In Seeds Of An Edible Fruit Tree, Dilinuer Shalimu, Jia Sun, Carol C. Baskin, Jerry M. Baskin, Liwei Sun, Yujun Liu

Biology Faculty Publications

The transition from seed dormancy to germination is triggered by environmental factors, and in pomegranate (Punica granatum) seeds higher germination percentages are achieved by warm + cold stratification rather than by cold stratification alone. Our objective was to define the pattern of internal oxidative changes in pomegranate seeds as dormancy was being broken by warm + cold stratification and by cold stratification alone. Embryos isolated from seeds after 1–42 days of warm stratification, after 56 days of warm stratification + 7, 28 or 56 days of cold stratification, and after 1–84 days of cold stratification alone, were used …


Novel Interactome Of Saccharomyces Cerevisiae Myosin Type Ii Identified By A Modified Integrated Membrane Yeast Two-Hybrid (Imyth) Screen, Ednalise Santiago, Pearl Akamine, Jamie Snider, Victoria Wong, Matthew Jessulat, Viktor Deineko, Alla Gagarinova, Hiroyuki Aoki, Zoran Minic, Sadhna Phanse, Andrea San Antonio, Luis A Cubano, Brian C. Rymond, Mohan Babu, Igor Stagljar, Jose R. Rodriguez-Medina May 2016

Novel Interactome Of Saccharomyces Cerevisiae Myosin Type Ii Identified By A Modified Integrated Membrane Yeast Two-Hybrid (Imyth) Screen, Ednalise Santiago, Pearl Akamine, Jamie Snider, Victoria Wong, Matthew Jessulat, Viktor Deineko, Alla Gagarinova, Hiroyuki Aoki, Zoran Minic, Sadhna Phanse, Andrea San Antonio, Luis A Cubano, Brian C. Rymond, Mohan Babu, Igor Stagljar, Jose R. Rodriguez-Medina

Biology Faculty Publications

Nonmuscle myosin type II (Myo1p) is required for cytokinesis in the budding yeast Saccharomyces cerevisiae. Loss of Myo1p activity has been associated with growth abnormalities and enhanced sensitivity to osmotic stress, making it an appealing antifungal therapeutic target. The Myo1p tail-only domain was previously reported to have functional activity equivalent to the full-length Myo1p whereas the head-only domain did not. Since Myo1p tail-only constructs are biologically active, the tail domain must have additional functions beyond its previously described role in myosin dimerization or trimerization. The identification of new Myo1p-interacting proteins may shed light on the other …


Population Dynamics Based On Resource Availability & Founding Effects: Live & Computational Models, Samuel Potter, Rebecca M. Krall, Susan Mayo, Diane Johnson, Kimberly J. Zeidler-Watters, Robin L. Cooper May 2016

Population Dynamics Based On Resource Availability & Founding Effects: Live & Computational Models, Samuel Potter, Rebecca M. Krall, Susan Mayo, Diane Johnson, Kimberly J. Zeidler-Watters, Robin L. Cooper

Biology Faculty Publications

With the looming global population crisis, it is more important now than ever that students understand what factors influence population dynamics. We present three learning modules with authentic, student-centered investigations that explore rates of population growth and the importance of resources. These interdisciplinary modules integrate biology, mathematics, and computer-literacy concepts aligned with the Next Generation Science Standards. The activities are appropriate for middle and high school science classes and for introductory college-level biology courses. The modules incorporate experimentation, data collection and analysis, drawing conclusions, and application of studied principles to explore factors affecting population dynamics in fruit flies. The variables …


Origins And Relationships Of The Mixed Mesophytic Forest Of Oregon-Idaho, China, And Kentucky: Review And Synthesis, Jerry M. Baskin, Carol C. Baskin Apr 2016

Origins And Relationships Of The Mixed Mesophytic Forest Of Oregon-Idaho, China, And Kentucky: Review And Synthesis, Jerry M. Baskin, Carol C. Baskin

Biology Faculty Publications

The Arcto-Tertiary Geoflora concept of Ralph Chaney, that the Mixed Mesophytic Forest of eastern Asia and eastern North America are relicts of a Northern Hemisphere high-latitude circumglobal deciduous forest of the Late Cretaceous–Early Tertiary that migrated south to the temperate zone as an intact unit, was shown by Wolfe and others to be invalid. To explain the origin and development of these disjunct forests, Wolfe and Tiffney developed the boreotropical hypothesis. Accordingly, a paratropical (near-tropical) rainforest flora containing a mixture of tropical, paratropical, and temperate genera developed at several places in the middle latitudes of the Northern Hemisphere in the …


Effects Of Germination Season On Life History Traits And On Transgenerational Plasticity In Seed Dormancy In A Cold Desert Annual, Juan J. Lu, Dun Y. Tan, Carol C. Baskin, Jerry M. Baskin Apr 2016

Effects Of Germination Season On Life History Traits And On Transgenerational Plasticity In Seed Dormancy In A Cold Desert Annual, Juan J. Lu, Dun Y. Tan, Carol C. Baskin, Jerry M. Baskin

Biology Faculty Publications

The maternal environment can influence the intensity of seed dormancy and thus seasonal germination timing and post-germination life history traits. We tested the hypotheses that germination season influences phenotypic expression of post-germination life history traits in the cold desert annual Isatis violascens and that plants from autumn- and spring-germinating seeds produce different proportions of seeds with nondeep and intermediate physiological dormancy (PD). Seeds were sown in summer and flexibility in various life history traits determined for plants that germinated in autumn and in spring. A higher percentage of spring- than of autumn-germinating plants survived the seedling stage, and all surviving …


Comparative Analysis Of Ear-Hole Closure Identifies Epimorphic Regeneration As A Discrete Trait In Mammals, Thomas R. Gawriluk, Jennifer Simkin, Katherine L. Thompson, Shishir K. Biswas, Zak Clare-Salzler, John M. Kimani, Stephen G. Kiama, Jeramiah James Smith, Vanessa O. Ezenwa, Ashley W. Seifert Apr 2016

Comparative Analysis Of Ear-Hole Closure Identifies Epimorphic Regeneration As A Discrete Trait In Mammals, Thomas R. Gawriluk, Jennifer Simkin, Katherine L. Thompson, Shishir K. Biswas, Zak Clare-Salzler, John M. Kimani, Stephen G. Kiama, Jeramiah James Smith, Vanessa O. Ezenwa, Ashley W. Seifert

Biology Faculty Publications

Why mammals have poor regenerative ability has remained a long-standing question in biology. In regenerating vertebrates, injury can induce a process known as epimorphic regeneration to replace damaged structures. Using a 4-mm ear punch assay across multiple mammalian species, here we show that several Acomys spp. (spiny mice) and Oryctolagus cuniculus completely regenerate tissue, whereas other rodents including MRL/MpJ ‘healer’ mice heal similar injuries by scarring. We demonstrate ear-hole closure is independent of ear size, and closure rate can be modelled with a cubic function. Cellular and genetic analyses reveal that injury induces blastema formation in Acomys cahirinus. …


Molecular Analyses Of Circadian Gene Variants Reveal Sex-Dependent Links Between Depression And Clocks, S-Q Shi, M. J. White, H. M. Borsetti, Julie S. Pendergast, A. Hida, C. M. Ciarleglio, P. A. De Verteuil, A. G. Cadar, C. Cala, D. G. Mcmahon, R. C. Shelton, S. M. Williams, C. H. Johnson Mar 2016

Molecular Analyses Of Circadian Gene Variants Reveal Sex-Dependent Links Between Depression And Clocks, S-Q Shi, M. J. White, H. M. Borsetti, Julie S. Pendergast, A. Hida, C. M. Ciarleglio, P. A. De Verteuil, A. G. Cadar, C. Cala, D. G. Mcmahon, R. C. Shelton, S. M. Williams, C. H. Johnson

Biology Faculty Publications

An extensive literature links circadian irregularities and/or sleep abnormalities to mood disorders. Despite the strong genetic component underlying many mood disorders, however, previous genetic associations between circadian clock gene variants and major depressive disorder (MDD) have been weak. We applied a combined molecular/functional and genetic association approach to circadian gene polymorphisms in sex-stratified populations of control subjects and case subjects suffering from MDD. This approach identified significant sex-dependent associations of common variants of the circadian clock genes hClock, hPer3 and hNpas2 with major depression and demonstrated functional effects of these polymorphisms on the expression or activity of the hCLOCK …


Optogenetic Stimulation Of Drosophila Heart Rate At Different Temperatures And Ca2+ Concentrations, Yuechen Zhu, Henry Uradu, Zana R. Majeed, Robin L. Cooper Feb 2016

Optogenetic Stimulation Of Drosophila Heart Rate At Different Temperatures And Ca2+ Concentrations, Yuechen Zhu, Henry Uradu, Zana R. Majeed, Robin L. Cooper

Biology Faculty Publications

Optogenetics is a revolutionary technique that enables noninvasive activation of electrically excitable cells. In mammals, heart rate has traditionally been modulated with pharmacological agents or direct stimulation of cardiac tissue with electrodes. However, implanted wires have been known to cause physical damage and damage from electrical currents. Here, we describe a proof of concept to optically drive cardiac function in a model organism, Drosophila melanogaster. We expressed the light sensitive channelrhodopsin protein ChR2.XXL in larval Drosophila hearts and examined light‐induced activation of cardiac tissue. After demonstrating optical stimulation of larval heart rate, the approach was tested at low temperature …


Analogous Cellular Contribution And Healing Mechanisms Following Digit Amputation And Phalangeal Fracture In Mice, Lindsay A. Dawson, Jennifer Simkin, Michelle Sauque, Maegan Pela, Teresa Palkowski, Ken Muneoka Feb 2016

Analogous Cellular Contribution And Healing Mechanisms Following Digit Amputation And Phalangeal Fracture In Mice, Lindsay A. Dawson, Jennifer Simkin, Michelle Sauque, Maegan Pela, Teresa Palkowski, Ken Muneoka

Biology Faculty Publications

Regeneration of amputated structures is severely limited in humans and mice, with complete regeneration restricted to the distal portion of the terminal phalanx (P3). Here, we investigate the dynamic tissue repair response of the second phalangeal element (P2) post amputation in the adult mouse, and show that the repair response of the amputated bone is similar to the proximal P2 bone fragment in fracture healing. The regeneration-incompetent P2 amputation response is characterized by periosteal endochondral ossification resulting in the deposition of new trabecular bone, corresponding to a significant increase in bone volume; however, this response is not associated with bone …


Human Gut Bacteria Are Sensitive To Melatonin And Express Endogenous Circadian Rhythmicity, Jiffin K. Paulose, John M. Wright, Akruti G. Patel, Vincent M. Cassone Jan 2016

Human Gut Bacteria Are Sensitive To Melatonin And Express Endogenous Circadian Rhythmicity, Jiffin K. Paulose, John M. Wright, Akruti G. Patel, Vincent M. Cassone

Biology Faculty Publications

Circadian rhythms are fundamental properties of most eukaryotes, but evidence of biological clocks that drive these rhythms in prokaryotes has been restricted to Cyanobacteria. In vertebrates, the gastrointestinal system expresses circadian patterns of gene expression, motility and secretion in vivo and in vitro, and recent studies suggest that the enteric microbiome is regulated by the host’s circadian clock. However, it is not clear how the host’s clock regulates the microbiome. Here, we demonstrate at least one species of commensal bacterium from the human gastrointestinal system, Enterobacter aerogenes, is sensitive to the neurohormone melatonin, which is secreted into the …


Modulatory Action By The Serotonergic System: Behavior And Neurophysiology In Drosophila Melanogaster, Zana R Majeed, Esraa Abdeljaber, Robin Soveland, Kristin Cornwell, Aubrey Bankemper, Felicitas Koch, Robin L. Cooper Jan 2016

Modulatory Action By The Serotonergic System: Behavior And Neurophysiology In Drosophila Melanogaster, Zana R Majeed, Esraa Abdeljaber, Robin Soveland, Kristin Cornwell, Aubrey Bankemper, Felicitas Koch, Robin L. Cooper

Biology Faculty Publications

Serotonin modulates various physiological processes and behaviors. This study investigates the role of 5-HT in locomotion and feeding behaviors as well as in modulation of sensory-motor circuits. The 5-HT biosynthesis was dysregulated by feeding Drosophila larvae 5-HT, a 5-HT precursor, or an inhibitor of tryptophan hydroxylase during early stages of development. The effects of feeding fluoxetine, a selective serotonin reuptake inhibitor, during early second instars were also examined. 5-HT receptor subtypes were manipulated using RNA interference mediated knockdown and 5-HT receptor insertional mutations. Moreover, synaptic transmission at 5-HT neurons was blocked or enhanced in both larvae and adult flies. The …


Evolution Of The Vertebrate Claudin Gene Family: Insights From A Basal Vertebrate, The Sea Lamprey, Christian Mukendi, Nicholas Dean, Rushil Lala, Jeramiah J. Smith, Marianne E Bronner, Natalya V. Nikitina Jan 2016

Evolution Of The Vertebrate Claudin Gene Family: Insights From A Basal Vertebrate, The Sea Lamprey, Christian Mukendi, Nicholas Dean, Rushil Lala, Jeramiah J. Smith, Marianne E Bronner, Natalya V. Nikitina

Biology Faculty Publications

Claudins are major constituents of tight junctions, contributing both to their intercellular sealing and selective permeability properties. While claudins and claudin-like molecules are present in some invertebrates, the association of claudins with tight junctions has been conclusively documented only in vertebrates. Here we report the sequencing, phylogenetic analysis and comprehensive spatiotemporal expression analysis of the entire claudin gene family in the basal extant vertebrate, the sea lamprey. Our results demonstrate that clear orthologues to about half of all mammalian claudins are present in the lamprey, suggesting that at least one round of whole genome duplication contributed to the diversification of …