Browsing by Author "University of Minnesota Duluth. Department of Biology"
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Item Accelerating Tuberculosis Drug Discovery by High Throughput Screening (2016-02-19)(2016) Arora, Kriti; University of Minnesota Duluth. Department of BiologyTuberculosis (TB) continues to be a leading killer of people worldwide infecting an estimated one-third of the world population and causing an 1.5 million deaths in 2014 alone. The current therapeutic regimen for drug-sensitive disease consists of 6-months of chemotherapy with agents that are associated with adverse events and toxicities leading to non-compliance. Additionally HIV-TB co-infection and the spread of drug-resistant TB underscores the need for discovery of new drugs that would shorten the course of chemotherapy. The Tuberculosis Drug Accelerator Program was born out of this urgent need and is a Gates Foundation funded collaborative effort between pharmaceutical companies and academic institutions. As part of this initiative we have conducted the largest global screening effort againstMycobacterium tuberculosis at the Tuberculosis Research Section (NIAID, NIH) in partnership with Merck, Bayer, AstraZeneca, EISAI, Pfizer and the University of Dundee. This screening campaign has generated several hit compounds which are currently progressing through our formal hit assessment cascade. The aim of the program is to increase early attrition rates so that only the best compounds move forward into preclinical development with the ultimate goal of declaring a new clinical candidate(s) by 2019 and a new regimen by 2024.Item Autonomous Self-Fertilization and Limited Outcrossing in Linum sulcatum (2015-03-13)(2015) Jahnke, Matthew; University of Minnesota Duluth. Department of BiologyItem BioChat (2003-12)(University of Minnesota Duluth, 2003-12) University of Minnesota Duluth. Department of BiologyItem Biogeochemical and food web studies in lakes large and small (2019-10-11)(2019) Ozersky, Ted; University of Minnesota Duluth. Department of BiologyMy lab studies the ecology and biogeochemistry of lake ecosystems. In this talk I will highlight three research projects that my students, collaborators and I have been pursuing over the past five years. First, I will discuss our work on the way invasive zebra and quagga (dreissenid) mussels affect thebiogeochemistry of invaded lakes and how the impacts of dreissenids change with environmental setting. I will also describe our work on uncovering the seldom-studied ecological processes that occur during the winter in small and large ice-covered lakes. The third project I will present examines environmental controls on growth of benthic algae in large lake ecosystems, including the Laurentian Great Lakes and Russia’s Lake Baikal. I will finish by discussing my plans for future research.Item BURST and SURP Poster Presentations (2021-08-06)(2021) University of Minnesota Duluth. Department of Biology; University of Minnesota Duluth. Department of Chemistry and BiochemistryStudents in the Biology Undergraduate Research in Science and Technology (BURST) and the Chemistry and Biochemistry Summer Undergraduate Research Program (SURP) will present the research they have been working on with faculty mentors throughout the summer. There will be an awards ceremony for both programs to follow.Item Cascades and Connectivity: The Influence of Spatial Scale on Understanding Ecosystem Processes (2015-02-27)(2015) University of Minnesota Duluth. Department of Biology; Nibbelink, Nate; Hrabik, TomDr. Nate Nibbelink of the University of Georgia speaks on Cascades and Connectivity: The Influence of Spatial Scale on Understanding Ecosystem ProcessesItem Chemical Evolution: How Survival of the Fittest Applies to Molecules and Leads to Life (2016-02-12)(2016) Shaw, George; University of Minnesota Duluth. Department of Earth and Environmental Sciences; University of Minnesota Duluth. Department of BiologyItem Chromatin/Nuclear Architecture Roles in Chromosome Structure and Function (2021-01-15)(2021) Johansen, Kristen; University of Minnesota Duluth. Department of BiologyAlthough early paradigms for regulation of gene expression focused almost exclusively on transcription factor binding and recruitment of the RNA polymerase, we now know that gene expression levels can be exquisitely calibrated by chromatin structure and nuclear architectural influences. And although histone modifications were first described as a "code" linked to "active" or "silent" chromatin states, work in my lab and others are revealing how these marks play a much more dynamic role in modulating gene function and chromosome behavior. In this presentation I will propose a model for enzymatic and non-enzymatic mechanisms by which the JIL-1 H3S10 kinase influences chromatin structure and chromosome architectural organization, and discuss developmental and physiological consequences of JIL-1 dysfunction.Item Coordinated response efforts to the red swamp crayfish invasion in Michigan, U.S.A. (2020-10-09)(2020) Roth, Brian; University of Minnesota Duluth. Department of BiologyNative to the southeastern United States, red swamp crayfish (Procambarus clarkia) currently have a near-global distribution as a consequence of purposeful and accidental introductions. Their effects in invaded ecosystems are often dramatic, and include negative effects on native amphibians, macrophytes, water quality, and native crayfish species. Red swamp crayfish construct extensive burrows and are demonstrated to undermine water control structures and enhance erosion in invaded systems. In July of 2017, red swamp crayfish were confirmed in several waterbodies in Michigan including a natural lake, residential ponds, and golf course waterways. Their discovery led to the development of a multifaceted and coordinated response plan involving MSU along with multiple state and federal agencies. This response plan includes early detection, genetic determination of source populations, life history studies, and the evaluation of novel and traditional control methodologies. Crayfish are notoriously difficult to eradicate, and little information exists on red swamp crayfish invasions at this latitude to guide eradication efforts. As a consequence, our research provides the unique opportunity to inform efforts to control this species around the world. This seminar will provide an overview of the red swamp crayfish invasion in Michigan and will detail the coordinated effort to eradicate this species in the state.Item Cortical representations of social deficits gated by cerebellum dysregulation (2021-03-05)(2021) Yang, Amy; University of Minnesota Duluth. Department of BiologyPatients who suffer neuropsychiatric disorders, including autism, schizophrenia, depression and Alzheimer's disease, often show abnormal social interaction. Therefore, it is important to understand the neural basis of social behavior in search of innovative treatments. Emerging evidence suggests that the cerebellum plays a key role in the neural networks essential for social functions. To investigate the mechanisms, we manipulated the cerebellar activity in a mouse model by precisely controlling the firing of a distinct population of neurons. This manipulation specifically impaired remembrance of previously encountered conspecifics, i.e., social recognition memory. We furthered [sic] delineated the anatomical and functional connections between the cerebellum and the cerebrum that mediate social memory. These insights will help develop clinical interventions for mental illness.Item Darwin's Passion for Plants (2021-02-05)(2021) Moran, Robbin; University of Minnesota Duluth. Department of BiologyAfter the Origin of Species was published in 1859, Charles Darwin wrote six books completely dedicated to plants. This talk briefly describes what those books contains [sic] and why they were important. Did you know that Darwin was the first scientist to demonstrate that some plants attract, trap, and digest insects? Come hear about Darwin and plants - you won't think of him as a [sic] just a zoologist anymore.Item Developing Science Identities in Undergraduates Underrepresented in the Sciences (2014-10-24)(2014) Prunuske, Amy; University of Minnesota Duluth. Department of BiologyItem Dissemination of RasV12-transformed cells requires the mechanosensitive channel Piezo (2020-09-11)(2020) Lee, Jiae; University of Minnesota Duluth. Department of BiologyDissemination of transformed cells is a key process in metastasis. Despite its importance, how transformed cells disseminate from an intact tissue and enter the circulation is poorly understood. Here, we use a fully developed tissue, Drosophila midgut, and describe the morphologically distinct steps and the cellular events occurring over the course of RasV12- transformed cell dissemination. Notably, RasV12-transformed cells formed the Actin- and Cortactin-rich invasive protrusions that were important for breaching the extracellular matrix (ECM) and visceral muscle. Furthermore, we uncovered the essential roles of the mechanosensory channel Piezo in orchestrating dissemination of RasV12-transformed cells. Collectively, our study establishes an in vivo model for studying how transformed cells migrate out from a complex tissue and provides unique insights into the roles of Piezo in invasive cell behavior.Item "Diversity, diversification, and the genomic basis of evolution in perennial crops and their wild relatives", a Seminar by Dr. Allison Miller Assoc. Professor, Saint Louis University (2014-04-11)(2014) Miller, Allison; Gross, Briana; University of Minnesota Duluth. Department of BiologyThe long-term goals of my research are to advance understanding of perennial plant evolution to better inform sustainable agriculture, crop improvement, and the conservation of plant genomic resources.Item Diving Deep: Microbial Diversity and Metabolic Potential in the Marine Deep Biosphere (2021-02-26)(2021) León Zayas, Rosa; University of Minnesota Duluth. Department of BiologyExploration of the deep ocean has expanded our understanding of oceanic ecosystems and yet still little is known about these deep sites on Earth. Some of the most poorly understood ecosystems are subsurface sedimentary environments and ultra-deep trenches, particularly as it pertains to the distribution of novel microbial lineages and their associated metabolic abilities. In this presentation, I will share an [sic] two examples of work that has advance [sic] our understanding of the distribution and metabolic potential of novel microbial lineages, such as those that are part of the Candidate Phyla Radiation, and archaeal lineages such as Bathyarchaea and Asgard archaea superphylum. Overall, this research seeks to reveal the metabolic potential of novel microbial lineages, which significantly contributes to our overall understanding of the ecosystem function of subsurfact sedimentary environments.Item DNA Barcoding as a Tool for Great Lakes Biological Assessment (2015-01-23)(2015) Trebitz, Annett; University of Minnesota Duluth. Department of BiologyItem DREAM interrupted: Establishing a CRISPR/Cas9 functional genomics pipeline in Caenorhabditis elegans (2021-02-19)(2021) Goetsch, Paul; University of Minnesota Duluth. Department of BiologyIn multicellular organisms, how do multiple cell types originate from one cell and one genome? A critical early cell fate decision is whether to develop as germline (reproductive) or soma (non-reproductive). My research focuses on assessing how the highly conserved DREAM transcriptional repressor complex maintains this germ vs. soma cell fate decisions. Loss of the Caenorhabditis elegans DREAM complex results in misexpression of germline genes in somaticcells, a phenomenon called a "soma-to-germline transition" that is commonly observed in cancer cells. To tackle how DREAM protects somatic cell identity, the Goetsch lab utilizes a functional genomic pipeline that integrates new CRISPR/Cas9 genome editing tools, high-throughput sequencing analysis, genetics, biochemistry, and cell biology. We are currently investigating how DREAM complex formation on chromatin mediates target gene repression. The 8-subunit DREAM complex contains 3 subcomponenets: an E2F-DP transcription factor heterodimer, a Retinoblastoma(Rb)-like pocket protein, and a 5-submit complex called MuvB. We hypothesize that MuvB chromatin occupancy, aided and stabilized by its association with E2F-DP and the Rb-like pocket protein, establishes and maintains target gene repression. Using CRISPR/Cas9 targeted mutagensis, we disrupted the interaction between MuvB and the sole C. elegans Rb-like pocket protein LIN-35. We expected that severing MuvB from the complex would destablize DREAM component assembly on chromatin and its repression of target genes. Instead, we observed that disrupting LIN-35-MuvB association did not affect DREAM chromatin occupancy, but we did observe upregulation of some DREAM target genes. Our current aim is to establish how the molecular events that drive DREAM complex formation contribute to target gene repression using our CRISPR/Cas9 functional genomics pipeline. In the future, we intend to use similar methods to illuminate how DREAM loss unlocks a network of downstream transcriptional processes that ultimately destabilizes somatic cell identity.Item The electric bacteria of Chesapeake Bay (2020-12-11)(2020) Malkin, Sairah; University of Minnesota Duluth. Department of BiologyCable bacteria are long filamentous bacteria that couple spatially separated electron donors and acceptors across centimeter-scale distances in aquatic sediments. Comprising the candidate genera Electrothrix and Electronema (Deltaproteobacteria), cable bacteria are capable of so-called electrogenic sulfur oxidation (e-SOX) in sediments, pairing oxidation sulfur oxidation from reducing depths to the reduction of oxygen or nitrate near the sediment surface. Accumulating evidence from diverse coastal marine systems is revealing that cable bacteria activity exerts a powerful control on sediment geochemistry, with profound consequences for geochemical cycling, at local- and potentially ecosystem-scales. For the past couple of years, we have been investigating the ecology of cable bacteria – defining their niche and biogeochemical role in Chesapeake Bay – with the aim of better constraining their quantitative biogeochemical function at the system scale. Year-round field sampling reveals cable bacteria are quantitatively important in winter and spring in the main stem of the Bay, which experiences seasonal anoxia, and are particularly responsive to sinking diatom phytodetritus in the spring. In this seminar, I will talk about the distribution and ecology of these “electric bacteria” and discuss some of the implications for geochemical cycling.Item Evolution and hybridization: Tales from charismatic megaflora (2020-10-16)(2020) Mitchell, Nora; University of Minnesota Duluth. Department of BiologyCharismatic megafauna may dominate the posters of conservation agencies, but charismatic megaFLORA are excellent and attention-grabbing taxa for esearching [sic] the ecology and volution [sic] of plants. Understanding the evolution and function of diversity in a group as large and varied as flowering plants requires evidence at many taxonomic, geographic, and temporal scales. I combine approaches from the microevolutionary to macroevolutionary scales to understand the history of two iconic plants: Protea of South Africa and Helianthus (sunflowers) of Texas. Using a combination of population genomics and phylogenomics, I find evidence for cryptic hybridization and species-level relationship in Protea that allow for a deeper understanding of trait evolution. I use experimental evolution to show that hybridization speeds adaptive evolution in Texas sunflowers, and phylogenetic comparative studies to place the role of hybridization in adaptive evolution in a larger context. Both of these systems allow for investigation into the mechanisms generating the astonishing diversity of plants.Item Evolution in Darwin's dream ponds: The cichlid fishes of the East African Big Lakes (2014-02-10)(2014) Salzburger, Walter; University of Minnesota Duluth. Large Lakes Observatory; University of Minnesota Duluth. Water Resources Science Graduate Program; University of Minnesota Duluth. Department of Geological Sciences; University of Minnesota Duluth. Department of Biology