Biology Commons^™

The Time Is Right For An Antarctic Biorepository Network, Kristin M. O’Brien, Elizabeth L. Crockett, Bryon J. Adams, Charles D. Amsler, Hannah J. Appiah-Madson, Allen Collins, Thomas Desvignes, Sarah Eppley, Multiple Additional Authors

Biology Faculty Publications and Presentations

Antarctica is a central driver of the Earth’s climate and health. The Southern Ocean surrounding Antarctica serves as a major sink for anthropogenic CO2 and heat (1), and the loss of Antarctic ice sheets contributes significantly to sea level rise and will continue to do so as the loss of ice sheets accelerates, with sufficient water stores to raise sea levels by 58 m (2). Antarctica's marine environment is home to a number of iconic species, and the terrestrial realm harbors a remarkable oasis for life, much of which has yet to be discovered (3). Distinctive oceanographic features of the …

Urban Green Roofs Can Support A Diversity Of Parasitoid Wasps, Aramee C. Diethelm, Susan Masta

Biology Faculty Publications and Presentations

Green roofs are often installed atop buildings to provide ecological services such as mitigating storm water runoff and cooling air within urban heat islands. We found that green roofs in Portland, Oregon, also can support biodiversity, including a diverse assemblage of parasitoid wasps, with 20 morphospecies from 10 families present on the four roofs we surveyed. The roofs with greater plant diversity and structural complexity harbored comparatively more parasitoid morphospecies than the structurally simpler Sedum-dominated roofs. The oldest green roof supported much greater diversity than the younger roofs, including a comparably planted roof three times its size. Parasitoid wasps from …

Upper Temperature Limit Of Larval Pacifc Lamprey Entosphenus Tridentatus: Implications For Conservation In A Warming Climate, Timothy A. Whitesel, Christina T. Uh

Biology Faculty Publications and Presentations

Climate models suggest that by 2100, maximum temperatures where many larval Pacific lamprey, Entosphenus tridentatus, rear now may approach 27–31 °C. Little information exists on whether larval Pacific lamprey can tolerate these temperatures. We used acclimated chronic exposure (ACE) and direct acute exposure (DAE) experiments to determine the water temperature that is lethal to larval Pacific lamprey and whether sublethal water temperatures influence larval burrowing behavior. After 30 days in ACE experiments, all larvae survived in temperatures averaging ≤ 27.7 °C, no larvae survived in temperatures averaging ≥ 30.7 °C and the ultimate upper incipient lethal temperature (UILT) was …

Cruise, A Tool For The Detection Of Iterons In Circular Rep-Encoding Single-Stranded Dna Viruses, Adam Jones, George W. Kasun, Joel Stover, Kenneth M. Stedman, Ignacio De La Higuera

Biology Faculty Publications and Presentations

Iterons are short, repeated DNA sequences that are important for the replication of circular single-stranded DNA viruses. No tools that can reliably predict iterons are currently available. The CRUcivirus Iteron SEarch (CRUISE) tool is a computational tool that identifies iteron candidates near stem-loop structures in viral genomes.

Micrornas Contribute To The Host Response To Coxiella Burnetii, Madhur Sachan, Katelynn Brann, Daniel E. Voth, Rahul Raghavan

Biology Faculty Publications and Presentations

MicroRNAs (miRNAs), a class of small non-coding RNAs, are critical to gene regulation in eukaryotes. They are involved in modulating a variety of physiological processes, including the host response to intracellular infections. Little is known about miRNA functions during infection by Coxiella burnetii, the causative agent of human Q fever. This bacterial pathogen establishes a large replicative vacuole within macrophages by manipulating host processes such as apoptosis and autophagy. We investigated miRNA expression in C. burnetii-infected macrophages and identified several miRNAs that were down- or up-regulated during infection. We further explored the functions of miR-143-3p, an miRNA whose …

Global Patterns Of Diversity And Metabolism Of Microbial Communities In Deep‑Sea Hydrothermal Vent Deposits, Zhichao Zhou, Emily St. John, Karthik Anantharaman, Anna-Louise Reysenbach

Biology Faculty Publications and Presentations

When deep-sea hydrothermal fluids mix with cold oxygenated fluids, minerals precipitate out of solution and form hydrothermal deposits. These actively venting deep-sea hydrothermal deposits support a rich diversity of thermophilic microorganisms which are involved in a range of carbon, sulfur, nitrogen, and hydrogen metabolisms. Global patterns of thermophilic microbial diversity in deep-sea hydrothermal ecosystems have illustrated the strong connectivity between geological processes and microbial colonization, but little is known about the genomic diversity and physiological potential of these novel taxa. Here we explore this genomic diversity in 42 metagenomes from four deep-sea hydrothermal vent fields and a deep-sea volcano collected …

Conflictos Entre Humanos Y Fauna Silvestre En Una Zona De Amortiguamiento De San Ramón, Costa Rica, Rebeca Solano-Gómez, José Manuel Mora

Biology Faculty Publications and Presentations

“Human-wildlife conflict in a buffer zone in San Ramón, Costa Rica”. Introduction: Currently, biodiversity is mainly managed by protected areas, but proximity with human activities results in conflicts, which are poorly studied in the tropics. Objective: To estimate human-wildlife conflict in the buffer zone of the Alberto Manuel Brenes Biological Reserve, San Ramón, Costa Rica. Methods: We interviewed the owners or managers of 59 farms. Results: We recorded 540 incidents, mostly with mammals (N=479); coyotes (Canis latrans) killed 1 074 animals in 183 attacks at 12 farms. We also recorded conflicts with jaguar, Panthera onca, puma, Puma concolor, ocelot, Leopardus …

Riqueza, Abundancia Relativa Y Actividad De Los Mamíferos De Una Reserva En Restauración En Costa Rica, Pablo Pacheco, Lucia López, Alison Vega Cambronero, José Manuel Mora

Biology Faculty Publications and Presentations

“Richness, relative abundance and activity of medium and large mammals of a reserve under restoration in Costa Rica”. Introduction: Private protected areas are a valuable complement to national systems of protected areas. The Sierra Zapote Reserve in Abangares, Costa Rica, established in 2000, protects 70 ha of advanced secondary forest, regenerating secondary forest and primary riparian forest. It is expected to favor faunal communities, like medium and large mammals, which are among the species most threatened by habitat loss and fragmentation; nevertheless; there is a lack of recent faunal assessments at Sierra Zapote. Objective: To assess the richness, relative abundance …

Weather And Climate Change Drive Annual Variation Of Reproduction By An Aerial Insectivore, Michael T. Murphy, Lucas J. Redmond, Amy C. Dolan, Nathan W. Cooper, Karen Shepherdson, Christopher Michael Chutter, Sarah Cancellieri

Biology Faculty Publications and Presentations

For many bird species, but especially aerial insectivores, reproduction depends on weather. Climate change is likely to intensify effects, but with uncertain consequences. We report 22 years of data on Eastern Kingbird (Tyrannus tyrannus) reproduction for two populations located in different hygric environments undergoing climate change; mesic central New York, USA, (NY; 12 years) and xeric southeastern Oregon, USA, (OR: 10 years). Laying date became earlier with increasing temperature in the 30-day period preceding laying in identical fashion at both sites, and in years of early laying, clutch size was larger, length of laying season increased, and failed …

Viruses In Astrobiology, Ignacio De La Higuera, Ester Lázaro

Biology Faculty Publications and Presentations

Viruses are the most abundant biological entities on Earth, and yet, they have not received enough consideration in astrobiology. Viruses are also extraordinarily diverse, which is evident in the types of relationships they establish with their host, their strategies to store and replicate their genetic information and the enormous diversity of genes they contain. A viral population, especially if it corresponds to a virus with an RNA genome, can contain an array of sequence variants that greatly exceeds what is present in most cell populations. The fact that viruses always need cellular resources to multiply means that they establish very …

Enriched Dietary Saturated Fatty Acids Induce Trained Immunity Via Ceramide Production That Enhances Severity Of Endotoxemia And Clearance Of Infection, Amy L. Seufert, James W. Hickman, Ste K. Traxler, Rachael M. Peterson, Trent A. Waugh, Sydney L. Lashley, Natalia Shulzhenko, Ruth J. Napier, Brooke A. Napier

Biology Faculty Publications and Presentations

Trained immunity is an innate immune memory response that is induced by a primary inflammatory stimulus that sensitizes monocytes and macrophages to a secondary pathogenic challenge, reprogramming the host response to infection and inflammatory disease. Dietary fatty acids can act as inflammatory stimuli, but it is unknown if they can act as the primary stimuli to induce trained immunity. Here we find mice fed a diet enriched exclusively in saturated fatty acids (ketogenic diet; KD) confer a hyper-inflammatory response to systemic lipopolysaccharide (LPS) and increased mortality, independent of diet-induced microbiome and hyperglycemia. We find KD alters the composition of the …

Could Annual Killifish Help Us Treat Macular Degeneration With Carmen Rodriguez, Carmen C. Rodriguez

PDXPLORES Podcast

In this episode of PDXPLORES, Carmen Rodriguez, a Ph.D. student in the biology department, discusses the Annual Killifish--a remarkable organism with the ability to survive long periods without oxygen or water--and how the unusual biology of this fish could unlock treatments for macular degeneration.

Click on the "Download" button to access the audio transcript.

Stable Coexistence Or Competitive Exclusion? Fern Endophytes Demonstrate Rapid Turnover Favoring A Dominant Fungus, Brett Steven Younginger, Nathan U. Stewart, Mehmet Ali Balkan, Daniel J. Ballhorn

Biology Faculty Publications and Presentations

Fungal endophytes are critical members of the plant microbiome, but their community dynamics throughout an entire growing season are underexplored. Additionally, most fungal endophyte research has centred on seed-reproducing hosts, while spore-reproducing plants also host endophytes and may be colonized by unique community members. In order to examine annual fungal endophyte community dynamics in a spore-reproducing host, we explored endophytes in a single population of ferns, Polystichum munitum, in the Pacific Northwest. Through metabarcoding, we characterized the community assembly and temporal turnover of foliar endophytes throughout a growing season. From these results, we selected endophytes with outsized representations in …

Not The Same Cure: Student Experiences In Course-Based Undergraduate Research Experiences Vary By Graduate Teaching Assistant, Emma C. Goodwin, Jessica R. Cary, Erin E. Shortlidge

Biology Faculty Publications and Presentations

To expose all undergraduate science students to the benefits of participating in research, many universities are integrating course-based undergraduate research experiences (CUREs) into their introductory biology laboratory curriculum. At large institutions, the bulk of introductory labs are instructed by graduate teaching assistants (GTAs). Graduate students, who are often teachers and researchers in training, may vary in their capacity to effectively teach undergraduates via the CURE model. To explore variation in GTA teaching and the subsequent outcomes for students, we used a case study research design at one institution where introductory biology students participate in GTA-taught CURE lab sections. We used …

Development Of The Seqcode: A Proposed Nomenclatural Code For Uncultivated Prokaryotes With Dna Sequences As Type, William Whitman, Maria Chuvochina, Brian P. Hedlund, Philip Hugenholtz, Konstantinos T. Konstantinidis, Alison E. Murray, Marike Palmer, Donovan H. Parks, Anna-Louise Reysenbach, Multiple Additional Authors

Biology Faculty Publications and Presentations

Over the last fifteen years, genomics has become fully integrated into prokaryotic systematics. The genomes of most type strains have been sequenced, genome sequence similarity is widely used for delineation of species, and phylogenomic methods are commonly used for classification of higher taxonomic ranks. Additionally, environmental genomics has revealed a vast diversity of as-yet-uncultivated taxa. In response to these developments, a new code of nomenclature, the Code of Nomenclature of Prokaryotes Described from Sequence Data (SeqCode), has been developed over the last two years to allow naming of Archaea and Bacteria using DNA sequences as the nomenclatural types. The …

Seqcode: A Nomenclatural Code For Prokaryotes Described From Sequence Data, Brian P. Hedlund, Maria Chuvochina, Philip Hugenholtz, Konstantinos T. Konstantinidis, Alison E. Murray, Marike Palmer, Donovan H. Parks, Alexander J. Probst, Anna-Louise Reysenbach, Multiple Additional Authors

Biology Faculty Publications and Presentations

Most prokaryotes are not available as pure cultures and therefore ineligible for naming under the rules and recommendations of the International Code of Nomenclature of Prokaryotes (ICNP). Here we summarize the development of the SeqCode, a code of nomenclature under which genome sequences serve as nomenclatural types. This code enables valid publication of names of prokaryotes based upon isolate genome, metagenome-assembled genome or single-amplified genome sequences. Otherwise, it is similar to the ICNP with regard to the formation of names and rules of priority. It operates through the SeqCode Registry (https://seqco.de/), a registration portal through which names and …

C3ar Plays Both Sides In Regulating Resistance To Bacterial Infections, Jesse A. Corcoran, Brooke A. Napier

Biology Faculty Publications and Presentations

Activation of the complement pathway results in the production of bioactive C3a, a product of C3 cleavage, which interacts with membrane-bound receptor C3aR to regulate innate immune cell function and outcome of bacterial infection. Specifically, previous research has identified mechanistically distinct and cell type–specific roles for C3aR in regulating innate immune cell inflammatory state, antimicrobial killing capacity, and metabolism. Historically, the production of C3a has been relegated to the serum; however, recent studies have provided evidence that various cell types can produce intracellular C3a that stimulates intracellular C3aR. In light of these new results, it is imperative that we revisit …

Orthotrichum Lyellii As An Active Moss Biomonitor: Examining The Interplay Between Ambient Pm10, Bulk Deposition And Heavy Metals In An Urban Environment, Scott Bradley Kiel

Dissertations and Theses

The importance of monitoring and preventing pollution in the environment is a globally recognized issue. Of the criteria pollutants outlined by the United States Environmental Protection Agency, particulate matter is among these least understood in relation to toxicity and most wide-spread. Many governments have employed continuous air quality monitoring networks to track ambient levels of particulate matter, but are often too widespread to capture the heterogeneity of the urban environment, especially for heavy metal deposition. In Portland, OR, the epiphytic moss Orthotrichum lyellii was successfully used as a low-cost passive biomonitor to increase the spatial resolution of pollution around the …

An Essential Role For Tungsten In The Ecology And Evolution Of A Previously Uncultivated Lineage Of Anaerobic, Thermophilic Archaea, Steffen Buessecker, Marike Palmer, Dengxun Lai, Joshua Dimapilis, Xavier Mayali, Damon Mosier, Jian-Yu Jiao, Daniel R. Colman, Anna-Louise Reysenbach, Multiple Additional Authors

Biology Faculty Publications and Presentations

Trace metals have been an important ingredient for life throughout Earth’s history. Here, we describe the genome-guided cultivation of a member of the elusive archaeal lineage Caldarchaeales (syn. Aigarchaeota), Wolframiiraptor gerlachensis, and its growth dependence on tungsten. A metagenome-assembled genome (MAG) of W. gerlachensis encodes putative tungsten membrane transport systems, as well as pathways for anaerobic oxidation of sugars probably mediated by tungsten-dependent ferredoxin oxidoreductases that are expressed during growth. Catalyzed reporter deposition-fluorescence in-situ hybridization (CARD-FISH) and nanoscale secondary ion mass spectrometry (nanoSIMS) show that W. gerlachensis preferentially assimilates xylose. Phylogenetic analyses of 78 high-quality Wolframiiraptoraceae MAGs from …

The Relationship Between The Gut Microbiome And Sleep Examined Through Associated Human Disease, Jessica Flikkema

University Honors Theses

The crosstalk between the gut microbiome and sleep affects many aspects of human health. This paper looks at metabolic disorders affected by sleep deprivation, sleep disorders affected by the gut microbiome, and other disorders related to both systems. The possible mechanisms of disease are examined for obesity, diabetes, and irritable bowel syndrome as examples of metabolic diseases. Insomnia, narcolepsy, and obstructive sleep apnea as examples of sleep disorders. And hypertension, Alzheimer’s disease, and psychiatric diseases as examples of diseases related to both systems. Understanding of these mechanisms is then used to support probiotics, fecal microbiota transplants, and regulated sleep schedules …

Climate And Intraspecific Geographic Variation Of Nests And Eggs In The Eastern Kingbird Tyrannus Tyrannus, Samantha Marie Gillette

Dissertations and Theses

The reproductive success of birds is ultimately driven by the traits of nests, eggs, and incubation behavior and the interactions among them. Avian reproduction varies on large geographic scales, most prominently between tropic- vs. temperate-breeding species, but also on finer scales, such as along latitudinal and elevational geographic gradients. However, despite the importance of eggs and nests, how their traits vary geographically in response to differences in regional climate remains understudied.

We studied Eastern Kingbirds (Tyrannus tyrannus), which have been previously demonstrated to alter incubation length in response to local climate conditions. Our study sites, Kansas (KS), New …

In Sickness And In Health: Parasites Of Stranded Pacific Harbor Seals (Phoca Vitulina Richardii) In Northern Oregon And Southern Washington, Cecily Douglas Bronson

Dissertations and Theses

Parasites have the capability to infect virtually every living organism on the planet and have adapted to infiltrate every trophic level. Many species have complex indirect life cycles and rely upon hosts at different levels of the food web for growth and reproduction. In the marine environment, having a high level of parasite diversity is thought to indicate a more stable ecosystem than an environment with low parasite diversity. As one of the top predators in their environment and because of their amphibious behaviors, pinnipeds (seals and sea lions) are exposed to a wide variety of parasites, making them ideal …

Fitness Effects Of Somatic Mutations Accumulating During Vegetative Growth, Mitchell Cruzan, Matthew A. Streisfeld, Jaime A. Schwoch

Biology Faculty Publications and Presentations

The unique life form of plants promotes the accumulation of somatic mutations that can be passed to offspring in the next generation, because the same meristem cells responsible for vegetative growth also generate gametes for sexual reproduction. However, little is known about the consequences of somatic mutation accumulation for offspring fitness. We evaluate the fitness effects of somatic mutations in Mimulus guttatus by comparing progeny from self-pollinations made within the same flower (autogamy) to progeny from self-pollinations made between stems on the same plant (geitonogamy). The effects of somatic mutations are evident from this comparison, as autogamy leads to homozygosity …

Evaluation Of Postmortem Protein Expression In Determining Cause Of Death, Zoe Robinson

University Honors Theses

Cause of death differentiation during a medicolegal autopsy can be complicated by several factors, including sample conditions which can create uncertainty. Postmortem protein analysis has potential to be used as an additional evidentiary tool in determining cause of death. Proteomic biomarkers offer a method to directly measure physiological conditions at time of death that are stable in a postmortem state. Specific protein expression levels have been studied for their postmortem application in significantly differentiating many different causes of death. Work done in regard to asphyxial, toxicological, and traumatic deaths will be specifically discussed here. Proteins will be reviewed for potential …

Terrestrial Movements, Activity Patterns And Habitat Use By Kinosternon Scorpioides (Testudines: Kinosternidae) In Palo Verde National Park, Costa Rica, Jose M. Mora, Franklin E. Castaneda

Biology Faculty Publications and Presentations

The Scorpion Mud turtle, Kinosternon scorpioides, is a widely distributed, semiaquatic species known to engage in regular terrestrial movement and terrestrial estivation. We studied terrestrial behavior in this species in Palo Verde National Park, northwestern Costa Rica. We determined terrestrial activity patterns by searching for active individuals during transects along 3.4 km of trails. We determined the distance that turtles traveled between the wetlands and estivation sites by fitting 10 terrestrially active individuals with a thread-bobbin tracking device attached to the rear of the carapace. We identified sex and marked and measured every turtle found active. We accumulated 92 observations …

The Effect Of Media And Filtration In Inducing The Oxidative Stress Response In Escherichia Coli, Suzanne Hollingsworth

University Honors Theses

Escherichia coli grown in complex medium (LB), but not defined medium (DGC), arrest DNA replication when collected on membrane filters and resuspended in fresh media. The arrest is similar to that observed when cells are challenged with hydrogen peroxide. Yet, the reason behind this arrest is unknown.

I hypothesized that the arrest in replication in complex medium after filtering might be due to oxidative shock, and therefore cells grown in complex medium and filtered should induce an oxidative stress response similar to cells treated with hydrogen peroxide. Utilizing the indicator dye H₂DCFDA, which fluoresces in response to reactive …

Ours Lived Lived: Faculty Responses To Stem Students' Lived Experiences, Stan Nguyen

University Honors Theses

Science, technology, engineering and mathematics (STEM) fields have historically had low undergraduate retention rates. To aid in counteracting this, classroom exercises, or 'belonging interventions' can play a vital role in keeping new STEM students motivated through the "cultural shock" period of the college transition. However, much is still unknown about STEM instructors' perceptions on belonging interventions in STEM classrooms. Would understanding students' lives and experiences in the past and present help them make better informed decisions in their teaching practices?

To answer this question, we drew upon results from a belonging intervention conducted by the Biology Education Research (BER) group …

Characterizing The Functional Role Of Transcription Factor E In Archaeal Transcription, Madolyn Hofstetter, Michael Bartlett

Student Research Symposium

Archaea and eukaryotes share many homologous proteins and essential mechanisms for survival and DNA replication. It is proposed that Archaea are the ancestors of eukaryotes, suggesting that eukaryotic transcription evolved from the basic archaeal mechanisms. By studying the fundamentals of archaeal transcription, we are in turn understanding more about how eukaryotic transcription functions. Many human diseases are linked to mishaps and mutations in the process of transcribing DNA to mRNA, so it is essential to explore structures and how mutations in these structures affect the essential function of transcription, and if these mutations also play a role in human disease.

Using Wgcna To Examine Rnaseq Expression Data In The Annual Killifish Austrofundulus Limnaeus, Patrick Clouser, Jason Podrabsky

Student Research Symposium

Annual killifish (Austrofundulus limnaeus) live in ephemeral ponds of Venezuela. They have evolved a unique life history that includes experience embryonic diapause; a period of developmental dormancy and metabolic arrest that supports survival during the dry season. Developing and diapausing embryos are extremely resistant to environmental stresses; for example, they can survive for months without oxygen (anoxia). A. limnaeus’ tolerance to anoxia is an important survival mechanism as they can spend months buried in anoxic soil during development. I hypothesize that this extreme anoxia tolerance is supported by gene expression networks that are different from typical vertebrates. To evaluate this …

Visualization Of Eye Development In Annual Killifish Using Whole-Mount Immunohistochemistry, Carmen Z. Rodriguez, Jason Podrabsky

Student Research Symposium

Vertebrate eye development is highly conserved. Current models have identified the gene networks involved in eye development, but lack the context of extreme environmental conditions that challenge these fundamental programs. Typical vertebrates live for many years while annual killifishes can complete their entire adult lifespan in a matter of weeks. Thus, annual killifishes are a strong model for age-related diseases such as age-related macular degeneration (AMD); an irreversible loss of central vision. Annual killifishes enter embryonic diapause; a period of developmental and metabolic dormancy. These embryos are extremely resistant to environmental stresses such as hypoxia/anoxia that would cause irreparable damage …