Biology Commons^™

Mutagenetic Analysis Of The Minor Capsid Protein Vp3 Of The Archaeal Fusellovirus Ssv1, Laura Costal Lagarde

Student Research Symposium

Viruses, while often associated with disease, are integral to life and play an important role in the microbiome. Despite their importance in medical research, archaeal viruses, particularly those found in extreme environments, are not widely understood. The Sulfolobus Spindle-Shaped Viruses (SSVs) of the Fuselloviridae family are unique among viruses in that they do not kill their host, the archaeon Sulfolobus Solfataricus in volcanic hot springs, but rather slow its growth, allowing for halo assay assessments.The study focuses on the type virus SSV1, which is predominantly composed of the Major and Minor capsid proteins vp1 and vp3, respectively. Previous study has …

Describing Shen & Shen Ming Via A Hybrid Quantum Computational Model, Alex M. Cullen, Johnny Lemau

Student Research Symposium

Definitions for Traditional Chinese Medicine (TCM) terminology within the context of quantum biology (QB) have recently been proposed. These definitions aim to elucidate concepts such as qi meridians in TCM. Our study presents a hypothesis that seeks to provide an operational definition for Spirit (Shen) and Bright Spirit (Shen Ming) in TCM via a scoping review. We propose that Shen represents physical, phenomenological proto-consciousness/consciousness in the forms of computation, such as singular particles/bits/qubits, computers, organisms, or computational strategies, whereas Shen Ming may refer to emergent, quasi-physical meta-proto-consciousness/consciousness formed by coherent relationships of multiple orchestrated/integrated units of computation; manifesting itself as …

Exploring Factors That Contribute To Stem Transfer Student Sense Of Belonging, Brittney R. Gallant, Cate Pocitari

Student Research Symposium

There is an ongoing disconnect between the number of students who enter college intending to earn a STEM degree and the number of students who persist to degree, this is particularly true for transfer students. Sense of belonging has been named as a STEM persistence factor, yet how that belonging develops for transfer students is largely unknown. Here we used a mixed-methods design to explore the experiences of STEM transfer students at PSU (n=38). Participants completed a survey prior to participating in an interview. The survey and interviews explored their science identity, sense of belonging, and involvement in STEM-related activities. …

Histone Changes As A Response To Lactic Acid Selection In Cells Of Austrofundulus Limnaeus, Lori Tran, Jason Podrabsky, Chelsea Hughes

Student Research Symposium

The killifish Austrofundulus limnaeus is an extremophile native to small temporary ponds of Venezuela. Normal embryonic development of A. limnaeus is segmented into up to three stages of metabolic depression (diapause), and both developing and diapausing embryos can survive long bouts of the complete absence of oxygen (anoxia) by using anaerobic metabolic pathways. While there has been much focus on how mutations in DNA drive evolution, environmental stress can cause heritable changes to histone post-translational modifications (hPTMs) in multiple species. However, this evolutionary role of hPTMs has never been studied in A. limnaeus. Additionally, the possible evolutionary role of extracellular …

Qibc Analysis On Killifish Cells Under Anoxic Conditions, Jaina Canlas

Student Research Symposium

Faithful DNA replication is vital for all living organisms. Environmental stressors can cause a multitude of mutations and DNA lesions during replication leading to cell death if not accurately repaired. The annual killifish, Austrofundulus limnaeus, has a heightened tolerance to many known genotoxic stressors, including anoxia. Embryos of the annual killifish can survive months of anoxia during the dry season when the ephemeral ponds they inhabit, completely dry. During these exposures, they have shown they are capable of repairing substantial amounts of damaged DNA. This resilience has led us to hypothesize that A. limnaeus have enhanced DNA repair capabilities. …

Annual Killifish: Eye Development And Retinal Cell Regeneration, Carmen Z. Rodriguez

Student Research Symposium

Vertebrate eye development is highly conserved. Current models have allowed the understanding of gene expression patterns that support eye development, but lack the context of extreme environmental conditions that challenge these fundamental programs. Typical vertebrate life spans can be years, but annual killifish, Austrofundulus limnaeus, are able to complete their entire adult lifespan in only weeks. Thus, A. limnaeus is a strong model for age-related macular degeneration. A. limnaeus also experiences embryonic diapause; a period of developmental dormancy. Developing/diapausing embryos of A. limnaeus are resistant to environmental stresses such as hypoxia/anoxia that would cause irreparable damage to vital organs, such …

Locating Vitamin D Receptors (Vdrs) In Annual Killifish, Austrofundulus Limnaeus, Rosalia N. Tanori, Amie L. Romney, Jason E. Podrabsky

Student Research Symposium

Austrofundulus limnaeus, a species of annual killifish found in unpredictable temporary habitats in South America, has a profound ability to survive long periods without water and oxygen. This tolerance is associated with the ability to enter metabolic dormancy associated with diapause. Entrance into diapause and tolerance of environmental stress is governed by an interplay of genetic and environmental factors. The vitamin D receptor (VDR) is among these factors and plays a crucial role in determining if an embryo will enter diapause or actively develop. My work aims to identify the genomic locations of VDR proteins in the A. limnaeus genome …

Construction And Mutagenesis Of Ssv1 Mutants In Extreme Viruses, Lou Ann F. O'Connor, Jono Abshier, Kenneth M. Stedman

Student Research Symposium

Archaeal viruses with unique structures such as spindle-shaped virions are found abundantly in extreme environments like geothermal hot springs around the world. Among all spindle-shaped viruses, the model Sulfolobus Spindle-shaped Virus 1 (SSV1) is best studied. Creating the lemon-shaped or spindle-shaped virion structure are two proteins, VP1 as the major capsid protein, and VP3 as the minor capsid protein. The primary structure of VP1 consists of a proteolytic cleavage site at position 66 that is believed to be necessary for virus evolution. Recent studies showed that genetic mutation of the amino acid, glutamate (E) at position 66 in VP1 which …

Autism Risk Gene Cul3 Alters Neuronal Morphology Via Caspase-3 Activity In Mouse Hippocampal Neurons, Qiang-Qiang Xia, Anju Singh, Jing Wang, Zhong Xin Xuan, Jeffrey D. Singer, Craig M. Powell

Biology Faculty Publications and Presentations

Autism Spectrum Disorders (ASDs) are neurodevelopmental disorders (NDDs) in which children display differences in social interaction/communication and repetitive stereotyped behaviors along with variable associated features. Cul3, a gene linked to ASD, encodes CUL3 (CULLIN-3), a protein that serves as a key component of a ubiquitin ligase complex with unclear function in neurons. Cul3 homozygous deletion in mice is embryonic lethal; thus, we examine the role of Cul3 deletion in early synapse development and neuronal morphology in hippocampal primary neuronal cultures. Homozygous deletion of Cul3 significantly decreased dendritic complexity and dendritic length, as well as axon formation. Synaptic spine density significantly …

Effective Dispersal Patterns In Prairie Plant Species Across Human-Modified Landscapes., Elizabeth C. Hendrickson, Mitchell B. Cruzan

Biology Faculty Publications and Presentations

Effective dispersal among plant populations is dependent on vector behaviour, landscape features and availability of adequate habitats. To capture landscape feature effects on dispersal, studies must be conducted at scales reflecting single-generation dispersal events (mesoscale). Many studies are conducted at large scales where genetic differentiation is due to dispersal occurring over multiple generations, making it difficult to interpret the effects of specific landscape features on vector behaviour. Genetic structure at the mesoscale may be determined by ecological and evolutionary processes, such as the consequences of vector behaviour on patterns of gene flow. We used chloroplast haplotypes and nuclear genome SNP …

Varecia Rubra (Red Ruffed Lemur) Diel Activity And Calling At Andranobe, Masoala National Park, Madagascar, Hannah Elena Hilden-Reid

Dissertations and Theses

With respect to the natural variation in abiotic and biotic conditions present between daytime and nighttime periods, many animal species show evolutionary adaptations specialized for diurnality, nocturnality, or crepuscularity. Biologists have traditionally viewed categorizations of this kind as fixed within taxonomic groups, emphasizing how intricately species’ survival is contingent on the ability to adapt to low light, high light, or twilight conditions. However, movement away from such distinct temporal niche categories began within chronobiological studies following the discovery of more flexible patterns of activity in numerous taxa during the late 1970s. This shift generated increased interest in elucidating the complex …

Genome Editing Using Crispr-Cas9 In Annual Killifish Species, Keria Moritsugu-Vandehey

University Honors Theses

CRISPR-Cas9 genome editing has been used successfully to knock out genes in model organisms such as zebrafish, turquoise killifish, and cichlid fish. CRISPR-Cas9 genome editing has not been verified in the annual killifish, Austrofundulus limnaeus. We hypothesize that targeted editing of the tyrosinase gene in embryos of A. limnaeus will lead to fish without the ability to produce black pigment. Embryos at the 1-cell stage were injected with a Cas9 cocktail containing a mix of guide RNA molecules that target the genomic sequence of the tyrosinase gene and either an mRNA coding for the Cas9 protein or Cas9 protein. …

Rhizobia-Legume Symbiosis Mediates Direct And Indirect Interactions Between Plants, Herbivores And Their Parasitoids, Carlos Bustos-Segura, Adrienne L. Godschalx, Lucas Malacari, Sergio Rasmann, Fanny Deiss, Daniel Ballhorn, Betty Benrey

Biology Faculty Publications and Presentations

Microorganisms associated with plant roots significantly impact the quality and quantity of plant defences. However, the bottom-up effects of soil microbes on the aboveground multitrophic interactions remain largely under studied. To address this gap, we investigated the chemically- mediated effects of nitrogen-fixing rhizobia on legume-herbivore-parasitoid multitrophic interactions. To address this, we initially examined the cascading effects of the rhizobia bean association on herbivore caterpillars, their parasitoids, and subsequently investigated how rhizobia influence on plant volatiles and extrafloral nectar. Our goal was to understand how these plant- mediated effects can affect parasitoids. Lima bean plants (Phaseoulus lunatus) inoculated with rhizobia exhibited …

Ubiquitous Filter Feeders Shape Open Ocean Microbial Community Structure And Function, Anne W. Thompson, Györgyi Nyerges, Kylee M. Brevick, Kelly Sutherland

Biology Faculty Publications and Presentations

The mechanism of mortality plays a large role in how microorganisms in the open ocean contribute to global energy and nutrient cycling. Salps are ubiquitous pelagic tunicates that are a well-known mortality source for large phototrophic microorganisms in coastal and high-latitude systems, but their impact on the immense populations of smaller prokaryotes in the tropical and subtropical open ocean gyres is not well quantified. We used robustly quantitative techniques to measure salp clearance and enrichment of specific microbial functional groups in the North Pacific Subtropical Gyre, one of the largest ecosystems on Earth. We discovered that salps are a previously …

A Genus In The Bacterial Phylum Aquificota Appears To Be Endemic To Aotearoa-New Zealand, Jean F. Power, Carlo R. Carere, Holly E. Welford, Daniel T. Hudson, Kevin C. Lee, John W. Moreau, Anna-Louise Reysenbach, Thijs J.G. Ettema, Multiple Additional Authors

Biology Faculty Publications and Presentations

Allopatric speciation has been difficult to examine among microorganisms, with prior reports of endemism restricted to sub-genus level taxa. Previous microbial community analysis via 16S rRNA gene sequencing of 925 geothermal springs from the Taupō Volcanic Zone (TVZ), Aotearoa-New Zealand, revealed widespread distribution and abundance of a single bacterial genus across 686 of these ecosystems (pH 1.2-9.6 and 17.4-99.8 °C). Here, we present evidence to suggest that this genus, Venenivibrio (phylum Aquificota), is endemic to Aotearoa-New Zealand. A specific environmental niche that increases habitat isolation was identified, with maximal read abundance of Venenivibrio occurring at pH 4-6, 50-70 °C, and …

Preparing Teaching Assistants To Facilitate Course-Based Undergraduate Research Experiences (Cures) In The Biological Sciences: A Call To Action, Erin Shortlidge, Amie M. Kern, Emma Goodwin, Jeffrey T. Olimpo

Biology Faculty Publications and Presentations

Course-based undergraduate research experiences (CUREs) offer an expanding avenue to engage students in real-world scientific practices. Increasingly, CUREs are instructed by graduate teaching assistants (TAs), yet TAs may be underprepared to facilitate and face unique barriers when teaching CUREs. Consequently, unless TAs are provided professional development (PD) and resources to teach CUREs effectively, they and their students may not reap the assumed benefits of CURE instruction. Here, we describe three perspectives – that of the CURE TA, the CURE designer/facilitator, and the CURE student – that are collectively intended to inform the development of tentative components of CURE TA PD. …

Germ Cell Recovery, Cryopreservation And Transplantation In The California White Sturgeon, Acipenser Transmontanus, Amie L. Romney, Danielle M. Myers, Fatima R. Martin, Tawney N. Scanlan, Stuart A. Meyers

Biology Faculty Publications and Presentations

The white sturgeon (Acipenser transmontanus) is the largest freshwater fish in North America. Because of the unique life history characteristics of sturgeon, including longevity, late maturation and long spawning intervals, their aquaculture can be a significant investment of resources. As a result of habitat loss and overharvesting, natural populations of white sturgeon are threatened and there is a growing effort to improve conservation aquaculture programs. Germ cell transplantation is an innovative technology previously demonstrated in a variety of fish species to be able to produce a surrogate broodstock. The technique relies upon optimal donor germ cell recovery and transplantation into …

Drivers Of Plankton Community Structure In Intermittent And Continuous Coastal Upwelling Systems–From Microbes And Microscale In-Situ Imaging To Large Scale Patterns, Moritz Schmid, Su Sponaugle, Anne W. Thompson, Kelly T. Sutherland, Robert Cowen

Biology Faculty Publications and Presentations

Eastern Boundary Systems support major fisheries whose early life stages depend on upwelling production. Upwelling can be highly variable at the regional scale, with substantial repercussions for new productivity and microbial loop activity. Studies that integrate the classic trophic web based on new production with the microbial loop are rare due to the range in body forms and sizes of the taxa. Underwater imaging can overcome this limitation, and with machine learning, enables fine resolution studies spanning large spatial scales. We used the In-situ Ichthyoplankton Imaging System (ISIIS) to investigate the drivers of plankton community structure in the northern California …

Big Boned: How Fat Storage And Other Adaptations Influenced Large Theropod Foraging Ecology, Cameron Pahl, Luis A. Ruedas

Biology Faculty Publications and Presentations

Dinosaur foraging ecology has been the subject of scientific interest for decades, yet much of what we understand about it remains hypothetical. We wrote an agent-based model (ABM) to simulate meat energy sources present in dinosaur environments, including carcasses of giant sauropods, along with living, huntable prey. Theropod dinosaurs modeled in this environment (specifically allosauroids, and more particularly, Allosaurus Marsh, 1877) were instantiated with heritable traits favorable to either hunting success or scavenging success. If hunter phenotypes were more reproductively successful, their traits were propagated into the population through their offspring, resulting in predator specialists. If selective pressure favored scavenger …

Comparative Skull Morphology Of California Sea Lions (Zalophus Californianus) And Steller Sea Lions (Eumetopias Jubatus) In The Pacific Northwest And Implications For Hybridization, Ada Iris Garcia Garcia

Dissertations and Theses

Eumetopias jubatus (Steller sea lions) that breed on the Oregon coast are smaller than those found both in Alaska and California. During the breeding season, male Zalophus californianus (California sea lions) move past E. jubatus rookeries in Oregon on their way to their breeding rookeries in Southern California. Introgression potentially could explain the difference in size of Oregon E. jubatus relative to remaining populations. At Portland State University (PSU), the marine mammal collection of the Museum of Vertebrate Biology has over 200 skulls of Z. californianus and E. jubatus from throughout northern Oregon and southern Washington. To assess whether morphologically …

Resistance To Dna Interstrand Crosslinks In Escherichia Coli Arises Through Prevention Rather Than Repair, Travis Kim Worley

Dissertations and Theses

DNA interstrand crosslinks are particularly lethal lesions that form in DNA when certain molecules intercalate between complementary strands of DNA and form covalent bonds with both strands. Once formed, these lesions present an absolute block to replication and transcription, ultimately resulting in cell death. Because of this lethality, chemicals that form DNA interstrand crosslinks are found in nature as defensive chemicals produced by plants and microbes. Moreover, crosslinking agents have proven effective the treatment of dysplastic conditions and are often first line chemotherapeutics.

However, cancer cells can become resistant to DNA interstrand crosslinks. Unlike other DNA lesions, the double-stranded nature …

Diverse And Variable Community Structure Of Picophytoplankton Across The Laurentian Great Lakes, John Gale, Carey P. Sweeney, Sarah Paver, Maureen L. Coleman, Anne W. Thompson

Biology Faculty Publications and Presentations

The Laurentian Great Lakes provide economic support to millions of people, drive biogeochemical cycling, and are an important natural laboratory for characterizing the fundamental components of aquatic ecosystems. Small phytoplankton are important contributors to the food web in much of the Laurentian Great Lakes. Here, for the first time, we reveal and quantify eight phenotypically distinct picophytoplankton populations across the Lakes using a multilaser flow cytometry approach, which distinguishes cells based on their pigment phenotype. The distributions and diversity of picophytoplankton flow populations varied across lakes and depths, with Lake Erie standing out with the highest diversity. By sequencing sorted …

Computational Analysis Of Plasma Lipidomics From Mice Fed Standard Chow And Ketogenic Diet, Amy L. Seufert, James W. Hickman, Jaewoo Choi, Brooke A. Napier

Biology Faculty Publications and Presentations

Dietary saturated fatty acids (SFAs) are upregulated in the blood circulation following digestion. A variety of circulating lipid species have been implicated in metabolic and inflammatory diseases; however, due to the extreme variability in serum or plasma lipid concentrations found in human studies, established reference ranges are still lacking, in addition to lipid specificity and diagnostic biomarkers. Mass spectrometry is widely used for identification of lipid species in the plasma, and there are many differences in sample extraction methods within the literature. We used ultra-high performance liquid chromatography (UPLC) coupled to a high-resolution hybrid triple quadrupole-time-of-flight (QToF) mass spectrometry (MS) …

Cullin 3–Mediated Regulation Of Intracellular Iron Homeostasis Promotes Thymic Invariant Nkt Cell Maturation, Emily L. Yarosz, Ajay Kumar, Jeffrey Singer, Cheong-Hee Chang

Biology Faculty Publications and Presentations

The E3 ubiquitin ligase cullin 3 (Cul3) is critical for invariant NKT (iNKT) cell development, as iNKT cells lacking Cul3 accumulate in the immature developmental stages. However, the mechanisms by which Cul3 mediates iNKT cell development remain unknown. In this study, we investigated the role of Cul3 in both immature and mature thymic iNKT cells using a mouse model with a T cell–specific deletion of Cul3. We found that mature iNKT cells lacking Cul3 proliferated and died more than wild-type cells did. These cells also displayed increased glucose metabolism and autophagy. Interestingly, we found that tight regulation of iron homeostasis …

Diving Into Aquatic Microbial Ecology And Evolution With Anne Thompson, Anne Thompson

PDXPLORES Podcast

On this episode of PDXPLORES, Assistant Professor of Biology, Anne Thompson, discusses her award-winning research work studying the diverse ecology of microorganisms found in Earth’s oceans. Thompson’s research examines microbial mortality impacts on the structure of oceanic food webs, carbon flow, and cell interactions that create dynamic patterns of nutrient and energy abundance within diverse aquatic ecosystems.

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Evolutionary Codependency: Insights Into The Mitonuclear Interaction Landscape From Experimental And Wild Caenorhabditis Nematodes, Suzanne Estes, Zachary P. Dietz, Vaishali Katju, Ulfar Bergthorsson

Biology Faculty Publications and Presentations

Aided by new technologies, the upsurgence of research into mitochondrial genome biology during the past 15 years suggests that we have misunderstood, and perhaps dramatically underestimated, the ongoing biological and evolutionary significance of our long-time symbiotic partner. While we have begun to scratch the surface of several topics, many questions regarding the nature of mutation and selection in the mitochondrial genome, and the nature of its relationship to the nuclear genome, remain unanswered. Although best known for their contributions to studies of developmental and aging biology, Caenorhabditis nematodes are increasingly recognized as excellent model systems to advance understanding in these …

Effects Of Heterozygous Deletion Of Autism-Related Gene Cullin-3 In Mice, Qiang-Qiang Xia, Angela K. Walker, Chenghu Song, Jing Wang, James A. Mobley, Jeffrey Singer, Anju Singh, Craig M. Powell

Biology Faculty Publications and Presentations

Autism Spectrum Disorder (ASD) is a developmental disorder in which children display repetitive behavior, restricted range of interests, and atypical social interaction and communication. CUL3, coding for a Cullin family scaffold protein mediating assembly of ubiquitin ligase complexes through BTB domain substrate-recruiting adaptors, has been identified as a high-risk gene for autism. Although complete knockout of Cul3 results in embryonic lethality, Cul3 heterozygous mice have reduced CUL3 protein, demonstrate comparable body weight, and display minimal behavioral differences including decreased spatial object recognition memory. In measures of reciprocal social interaction, Cul3 heterozygous mice behaved similarly to their wild-type littermates. In …

Embryonic Development Of Natural Annual Killifish Populations Of The Genus Austrolebias: Evolutionary Parallelism And The Role Of Environment, Hellen Schlueb, Daniel Blanco, Daniel García, Jason Podrabsky

Biology Faculty Publications and Presentations

1. Repeated, independent emergence of the same trait within different phylogenetic lineages is termed parallel evolution. It typically occurs as a result of similar selective pressures. Annual killifish have adapted to survive in the extreme habitat of temporary pools on three continents and present an especially amenable system for studying fundamental principles of evolutionary parallelism. When the pools dry, annual killifish embryos survive through the dry phase in the bottom substrate in a stage of dormancy—a diapause. The diapause is a complex set of three different developmental stages, none of which is obligate, thus leading to a multitude of potential developmental …

Pleurotus Spp. As Agents Of Mycoremediation: A Review, Colin Innes

University Honors Theses

Elemental and molecular contaminants of anthropogenic origin represent an increasing threat to virtually all terrestrial and aquatic environments as well as their surrounding atmosphere. The decontamination and restoration of these environments pose a significant and expensive challenge. Although chemical treatment or physical removal of contaminated substrates often is the most direct response to eliminate contaminants, due to the complexity and sensitivity of many natural systems, technologies involving biological remediation can provide viable alternatives. While plant, bacterial, and fungal organisms have the abilities to accumulate or to metabolize toxic compounds, fungal organisms are uniquely suited to do so. Their fast growth …

Novel Viruses Of The Family Partitiviridae Discovered In Saccharomyces Cerevisiae, Angela M. Crabtree, Ignacio De La Higuera, Kenneth Stedman, Multiple Additional Authors

Biology Faculty Publications and Presentations

It has been 49 years since the last discovery of a new virus family in the model yeast Saccharomyces cerevisiae. A large-scale screen to determine the diversity of double-stranded RNA (dsRNA) viruses in S. cerevisiae has identified multiple novel viruses from the family Partitiviridae that have been previously shown to infect plants, fungi, protozoans, and insects. Most S. cerevisiae partitiviruses (ScPVs) are associated with strains of yeasts isolated from coffee and cacao beans. The presence of partitiviruses was confirmed by sequencing the viral dsRNAs and purifying and visualizing isometric, non-enveloped viral particles. ScPVs have a typical bipartite …