Biology Commons^™

Cooperative Stimulation Of Megakaryocytic Differentiation By Gfi1b Gene Targets Kindlin3 And Talin1, Divya Singh, Ghanshyam Upadhyay, Ananya Sengupta, Mohammed A. Biplob, Shaleen Chakyayil, Tiji George, Shireen Saleque

Publications and Research

Understanding the production and differentiation of megakaryocytes from progenitors is crucial for realizing the biology and functions of these vital cells. Previous gene ablation studies demonstrated the essential role of the transcriptional repressor Gfi1b (growth factor independence 1b) in the generation of both erythroid and megakaryocytic cells. However, our recent work has demonstrated the down-regulation of this factor during megakaryocytic differentiation. In this study we identify two new gene targets of Gfi1b, the cytoskeletal proteins Kindlin3 and Talin1, and demonstrate the inverse expression and functions of these cytoskeletal targets relative to Gfi1b, during megakaryocytic differentiation. Both kindlin3 and talin1 promoters …

The Variation Of Productivity And Its Allocation Along A Tropical Elevation Gradient: A Whole Carbon Budget Perspective, Yadvinder Malhi, Cécile A. J. Girardin, Gregory R. Goldsmith, Christopher E. Doughty, Norma Salinas, Daniel B. Metcalfe, Walter Huaraca Huasco, Javier E. Silva-Espejo, Jhon Del Aguilla-Pasquell, Filio Farfán Amézquita, Luiz E.O.C. Aragão, Rossella Guerrieri, Françoise Yoko Ishida, Nur Bahar, William Farfan-Rios, Oliver L. Phillips, Patrick Meir, Miles Silman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

• Why do forest productivity and biomass decline with elevation? To address this question, research to date generally has focused on correlative approaches describing changes in woody growth and biomass with elevation.
  
  
• We present a novel, mechanistic approach to this question by quantifying the autotrophic carbon budget in 16 forest plots along a 3300 m elevation transect in Peru.
  
  
• Low growth rates at high elevations appear primarily driven by low gross primary productivity (GPP), with little shift in either carbon use efficiency (CUE) or allocation of net primary productivity (NPP) between wood, fine roots and canopy. The lack of trend in …

The European Eel Nccβ Gene Encodes A Thiazide-Resistant Na-Cl Cotransporter, Erika Moreno, Consuelo Plata, Alejandro Rodríguez-Gama, Eduardo R. Argaiz, Norma Vázquez, Karla Leyva, Carmen Y. Hernández-Carballo, León Islas, Christopher P. Cutler, Diana Pacheco-Alvarez, Adriana Mercado, Raquel Cariño-Cortés, Gerardo Gamba

Biology: Faculty Publications

The thiazide-sensitive Na-Cl cotransporter (NCC) is the major pathway for salt reabsorption in the mammalian distal convoluted tubule. NCC plays a key role in the regulation of blood pressure. Its inhibition with thiazides constitutes the primary baseline therapy for arterial hypertension. However, the thiazide-binding site in NCC is unknown. Mammals have only one gene encoding for NCC. The eel, however, contains a duplicate gene. NCCα is an ortholog of mammalian NCC and is expressed in the kidney. NCCβ is present in the apical membrane of the rectum. Here we cloned and functionally characterized NCCβ from the European eel. The cRNA …

Biology Internship In Austria, Maria Gabriela Herrera, Valentina Ramirez

Trick to the Treat of Internships and Research

The summer biology internship in Austria is an excellent opportunity for students who desire to pursue the field of medicine. As part of the program, students will be assigned to the organ transplant team where they will have the opportunity to not only observe such surgeries, but also actually participate and assist during the procedure. Other possible specialties during this program include plastic surgery, orthopedic surgery, obstetrics and gynecology, and urology depending on availability. The selected students will travel to Graz, Austria and meet with the organ transplant team and learn how to prepare for and assist in surgery. The …

The Scripps Research Institute Summer Undergraduate Research Fellowship, Ezana Assefa

Trick to the Treat of Internships and Research

This program is a 10-week internship designed for undergraduates interested in the scientific field to engage in current research. Students have the option of requesting to work under three mentors, one of which they will be paired. Students will work in the lab with the principal investigator and other members of the lab. Along with working in the lab, students in the program will also attend bi-weekly talks/lectures from researchers, grad students, and professionals at TSRI as well as participating in two presentations and a final poster or oral presentation.

The Evolution Of Line-1 In Vertebrates, Stephane Boissinot, Akash Sookdeo

Publications and Research

The abundance and diversity of the LINE-1 (L1) retrotransposon differ greatly among vertebrates. Mammalian genomes contain hundreds of thousands L1s that have accumulated since the origin of mammals. A single group of very similar elements is active at a time in mammals, thus a single lineage of active families has evolved in this group. In contrast, non-mammalian genomes (fish, amphibians, reptiles) harbor a large diversity of concurrently transposing families, which are all represented by very small number of recently inserted copies. Why the pattern of diversity and abundance of L1 is so different among vertebrates remains unknown. To address this …

A New Timepiece: An Epigenetic Mitotic Clock, Brock C. Christensen, Karl T. Kelsey

Dartmouth Scholarship

A new mitotic clock and mathematical approach that incorporates DNA methylation biology common among human cell types provides a new tool for cancer epigenetics research.

Better Late Than Never: Effective Air-Borne Hearing Of Toads Delayed By Late Maturation Of The Tympanic Middle Ear Structures, Molly C. Womack, Jakob Christensen-Dalsgaard, Kim L. Hoke

Biology Faculty Publications

Most vertebrates have evolved a tympanic middle ear that enables effective hearing of airborne sound on land. Although inner ears develop during the tadpole stages of toads, tympanic middle ear structures are not complete until months after metamorphosis, potentially limiting the sensitivity of post-metamorphic juveniles to sounds in their environment. We tested the hearing of five species of toads to determine how delayed ear development impairs airborne auditory sensitivity. We performed auditory brainstem recordings to test the hearing of the toads and used micro-computed tomography and histology to relate the development of ear structures to hearing ability. We found a …

Sources, Distributions And Dynamics Of Dissolved Organic Matter In The Canada And Makarov Basins, Yuan Shen, Ronald Benner, Lisa L. Robbins, Jonathan G. Wynn

Faculty Publications

A comprehensive survey of dissolved organic carbon (DOC) and chromophoric dissolved organic matter (CDOM) was conducted in the Canada and Makarov Basins and adjacent seas during 2010–2012 to investigate the dynamics of dissolved organic matter (DOM) in the Arctic Ocean. Sources and distributions of DOM in polar surface waters were very heterogeneous and closely linked to hydrological conditions. Canada Basin surface waters had relatively low DOC concentrations (69 ± 6 μmol L−1), CDOM absorption (a325: 0.32 ± 0.07 m−1) and CDOM-derived lignin phenols (3 ± 0.4 nmol L−1), and high spectral slope values (S275–295: 31.7 ± …

Winter Warming Effects On Overwinter Survival, Energy Use, And Spring Emergence Of Cerotoma Trifurcata (Coleoptera: Chrysomelidae), Emily A. Berzitis, Heather A. Hager, Brent J Sinclair, Rebecca H. Hallett, Jonathan A. Newman

Biology Publications

1. Bean leaf beetle Cerotoma trifurcata (Förster) (Coleoptera: Chrysomelidae) is a pest of soybean in the U.S.A. and is becoming a concern in Canada. The projected increase in winter temperatures under climate change could affect overwinter survival, timing of spring emergence and, ultimately, the severity of this pest.
2. We assessed the potential effects of warmer winters in field experiments performed in three consecutive years. Three warming levels were applied: (i) heated approximately 4 °C above ambient; (ii) unheated with snow cover left intact; and (iii) unheated with snow cover removed. Survival and date of emergence were assessed in all years, and …

Oxidative Stress In Oocytes During Midprophase Induces Premature Loss Of Cohesion And Chromosome Segregation Errors, Adrienne T. Perkins, Thomas M. Das, Lauren C. Panzera, Sharon E. Bickel

Dartmouth Scholarship

In humans, errors in meiotic chromosome segregation that produce aneuploid gametes increase dramatically as women age, a phenomenon termed the "maternal age effect." During meiosis, cohesion between sister chromatids keeps recombinant homologs physically attached and premature loss of cohesion can lead to missegregation of homologs during meiosis I. A growing body of evidence suggests that meiotic cohesion deteriorates as oocytes age and contributes to the maternal age effect. One hallmark of aging cells is an increase in oxidative damage caused by reactive oxygen species (ROS). Therefore, increased oxidative damage in older oocytes may be one of the factors that leads …

Quantifying Life: A Computational Approach To Teaching Mathematics To Biology Students, Dmitry Kondrashov

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Territorial Movement Game, Jan Rychtar

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Designing And Mentoring In A Research Experience For Undergraduates, Alex Capaldi

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Experimenting With Mathematical Biology, Becky Sanft

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Zombies, Predatory Wasps And Consciousness, James K. Peterson

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

A Numerical Investigation Of A Simplified Human Birth Model, Roseanna Gossmann, Alexa Baumer, Lisa Fauci, Megan C. Leftwich

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Dynamics Of A Two Vector, Two Pathogen, Single Host Model, Caleb L. Adams

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Coastal Wetland Response To Sea‐Level Rise In A Fluvial Estuarine System, Karim Alizad, Scott C. Hagen, James T. Morris, Stephen C. Medeiros, Matthew V. Bilskie, John F. Weishampel

Faculty Publications

Coastal wetlands are likely to lose productivity under increasing rates of sea‐level rise (SLR). This study assessed a fluvial estuarine salt marsh system using the Hydro‐MEM model under four SLR scenarios. The Hydro‐MEM model was developed to apply the dynamics of SLR as well as capture the effects associated with the rate of SLR in the simulation. Additionally, the model uses constants derived from a 2‐year bioassay in the Apalachicola marsh system. In order to increase accuracy, the lidar‐based marsh platform topography was adjusted using Real Time Kinematic survey data. A river inflow boundary condition was also imposed to simulate …

Plant Electrical Signal Classification Based On Waveform Similarity, Yang Chen, Dong-Jie Zhao, Zi-Yang Wang, Zhong-Yi Wang, Guiliang Tang, Lan Huang

Michigan Tech Publications, Part 1

(1) Background: Plant electrical signals are important physiological traits which reflect plant physiological state. As a kind of phenotypic data, plant action potential (AP) evoked by external stimuli—e.g., electrical stimulation, environmental stress—may be associated with inhibition of gene expression related to stress tolerance. However, plant AP is a response to environment changes and full of variability. It is an aperiodic signal with refractory period, discontinuity, noise, and artifacts. In consequence, there are still challenges to automatically recognize and classify plant AP; (2) Methods: Therefore, we proposed an AP recognition algorithm based on dynamic difference threshold to extract all waveforms similar …

Mathematical Modeling Of Vaccine Noncompliance, Jordan A. Bauer

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Understanding Adipocyte Dynamics Through Mathematical Modeling, Katrina Johnson, Fred Adler

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Reproductive Schedule Of The Silver Shiner (Notropis Photogenis) In The Flint River Of Alabama, Kelly Hodgskins, Stephanie Greenleaf, Jonathan Hillman, Bruce Stallsmith

Southeastern Fishes Council Proceedings

Many river-dwelling species of fish are dependent upon and stimulated by fluctuations in river flow for successful reproduction. This is especially true of pelagophils, a reproductive guild whose eggs and larvae require free drifting on river currents for several days. Notropis photogenis (Silver Shiner) is a rheophilic species with a broad distribution from Ontario to the southeastern United States including northern tributaries to the Tennessee River in Alabama. Little is known of its reproductive biology. The purpose of this study was to describe aspects of reproductive biology such as timing and pattern of ovarian development and oocyte maturation of N. …

Purification Of 26s Proteasomes And Their Subcomplexes From Plants, Richard S. Marshall, David C. Gemperline, Richard D. Vierstra

Biology Faculty Research

The 26S proteasome is a highly dynamic, multisubunit, ATP-dependent protease that plays a central role in cellular housekeeping and many aspects of plant growth and development by degrading aberrant polypeptides and key cellular regulators that are first modified by ubiquitin. Although the 26S proteasome was originally enriched from plants over 30 years ago, only recently have significant advances been made in our ability to isolate and study the plant particle. Here, we describe two robust methods for purifying the 26S proteasome and its subcomplexes from Arabidopsis thaliana; one that involves conventional chromatography techniques to isolate the complex from wild-type …

Effects Of Parasitism And Mite Control Methods On European Starling Development, Aderinsola Oluwasikemi Odetunde

Theses and Dissertations

Certain developmental stressors can lead to developmental trade-offs in young organisms. Hematophagous ectoparasites are a common stressor experienced by European starlings, and we wished to explore what aspects of an ectoparasite infestation drove trade-offs. The first part of this study was to test the hypothesis that blood loss was the sole mediator of trade-offs due to hematophagous ectoparasite infestation. We used nestlings that were exposed to mites in the nests, nestlings in mite-reduced nests experiencing supplementary blood loss, and nestlings in mite reduced nests with no supplementary blood loss. We also used a new heat treatment to reduce mites in …

Large-Scale Off-Target Identification Using Fast And Accurate Dual Regularized One- Class Collaborative Filtering And Its Application To Drug Repurposing, Hansaim Lim, Aleksandar Poleksic, Yuan Yao, Hanghang Tong, Di He, Luke Zhuang, Patrick Meng, Lei Xie

Publications and Research

Target-based screening is one of the major approaches in drug discovery. Besides the intended target, unexpected drug off-target interactions often occur, and many of them have not been recognized and characterized. The off-target interactions can be responsible for either therapeutic or side effects. Thus, identifying the genome-wide off-targets of lead compounds or existing drugs will be critical for designing effective and safe drugs, and providing new opportunities for drug repurposing. Although many computational methods have been developed to predict drug-target interactions, they are either less accurate than the one that we are proposing here or computationally too intensive, thereby limiting …

Electro-Chemotactic Fields Induce Cooperative Movement Of Cns Cells, Shawn Mishra, Stephen Redenti, Maribel Vazquez

Publications and Research

Vision loss in adults with Age Related Macular Degeneration (AMD) is attributed to damage of retinal photoreceptor cells that initiate vision by absorbing light. Mouse models have suggested that transplantation of precursor cells may be a novel approach to restore vision. This project uses a combination of electrotactic and chemotactic stimuli to promote and guide CNS cell migration within a microdevice model.

What’S In The Gift? Towards A Molecular Dissection Of Nuptial Feeding In A Cricket, Yannick Pauchet, Natalie Wielsch, Paul A. Wilkinson, Aleš Svatoš, Scott K. Sakaluk, Richard H. Ffrench-Constant, David G. Heckel, John Hunt

Faculty Publications – Biological Sciences

Nuptial gifts produced by males and transferred to females during copulation are common in insects. Yet, their precise composition and subsequent physiological effects on the female recipient remain unresolved. Male decorated crickets Gryllodes sigillatus transfer a spermatophore to the female during copulation that is composed of an edible gift, the spermatophylax, and the ampulla that contains the ejaculate. After transfer of the spermatophore, the female detaches the spermatophylax and starts to eat it while sperm from the ampulla are evacuated into the female reproductive tract. When the female has finished consuming the spermatophylax, she detaches the ampulla and terminates sperm …

Glycoside Hydrolases Family 20 (Gh20) Represent Putative Virulence Factors That Are Shared By Animal Pathogenic Oomycetes, But Are Absent In Phytopathogens, Isabel Olivera, Katrina Fins, Sara Rodriguez, Sumayyah K. Abiff, Jaime Tartar, Aurelien Tartar

Biology Faculty Articles

Background

Although interest in animal pathogenic oomycetes is increasing, the molecular basis mediating oomycete-animal relationships remains virtually unknown. Crinkler (CRN) genes, which have been traditionally associated with the cytotoxic activity displayed by plant pathogenic oomycetes, were recently detected in transcriptome sequences from the entomopathogenic oomycete Lagenidium giganteum, suggesting that these genes may represent virulence factors conserved in both animal and plant pathogenic oomycetes. In order to further characterize the L. giganteum pathogenome, an on-going genomic survey was mined to reveal novel putative virulence factors, including canonical oomycete effectors Crinkler 13 (CRN13) orthologs. These novel sequences provided a basis to …

Rna-Seq Of Borrelia Burgdorferi In Multiple Phases Of Growth Reveals Insights Into The Dynamics Of Gene Expression, Transcriptome Architecture, And Noncoding Rnas, William K. Arnold, Christina R. Savage, Catherine A. Brissette, Janakiram Seshu, Jonathan Livny, Brian Stevenson

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Borrelia burgdorferi, the agent of Lyme disease, differentially expresses numerous genes and proteins as it cycles between mammalian hosts and tick vectors. Insights on regulatory mechanisms have been provided by earlier studies that examined B. burgdorferi gene expression patterns during cultivation. However, prior studies examined bacteria at only a single time point of cultivation, providing only a snapshot of what is likely a dynamic transcriptional program driving B. burgdorferi adaptations to changes during culture growth phases. To address that concern, we performed RNA sequencing (RNA-Seq) analysis of B. burgdorferi cultures at early-exponential, mid-exponential, and early-stationary phases …