Tag: Poster 71

Elucidating the Active Domain of a Novel Anti-inflammatory Protein Produced by Intestinal Bacteria

Presenter: Lila Kaye

Faculty Mentor: Karen Guillemin, Annah Rolig

Presentation Type: Poster 71

Primary Research Area: Science

Major: Biology

Bacteria play an important role in the health of their host organism; pathogenic lines signal danger, which induces
a host immune response, while commensal, or resident, bacteria signal to reduce or prevent such an immune response. The ability of a resident organism to communicate with its host to alter immune system function is a burgeoning topic in the molecular biology field, offering a potentially rich source of biotherapeutics to treat illnesses. Researchers in the Guillemin laboratory identified a novel bacterial protein, produced by resident bacteria, which reduces intestinal innate immune responses in zebrafish hosts. Zebrafish are a good model organism for humans because of high replicability, easy gnotobiology, and their translucent larvae allow easily monitoring of host cells. I
aim to carry out a structure-function analysis of this protein. I will determine which domain has the anti-inflammatory activity using systematic deletions of the gene sequence. The protein has one region with homology to a human anti- inflammatory cytokine, a protein that controls neutrophil behavior as part of the immune system. We hypothesize that this domain will be important in the bacterial protein’s function. This would suggest that this bacterial resident mimics a host protein to control the host immune response. This anti-inflammatory protein could be a fresh tool to fight chronic inflammatory diseases in humans, ones often caused by disunion between gut microbes and their host.

Determining Soil Organic Carbon Values in Association With Vegetation Community Types in the Chewaucan River Basin

Presenter(s): Aaron Lefore − Environmental Science

Faculty Mentor(s): Lucas Silva, Schyler Reis

Poster 71

Research Area: Physical Science

The terrestrial carbon pool, especially soils, have the potential to sequester large amounts of carbon by way of below ground carbon flux. However, the degree of carbon sequestration into soils is dependent upon the structure of the vegetation communities inhabiting them and the unique qualities of the soil itself. This study focuses on below ground carbon concentrations, specifically soil organic carbon (SOC), in relation to vegetation communities in the Chewaucan River Basin in southern Oregon. Over time, management practices within the Chewaucan site have resulted in major vegetation shifts, defined by woody Juniper encroachment, cheatgrass invasion, and dryland agriculture practices. To calculate SOC, cores from the top 10cm of soil were taken from different vegetation community plots across the site that included Juniper, Ponderosa Pine, sagebrush, Juniper/Pine, and alfalfa. Samples were dried to determine bulk density, texture, and Munsell color system rating. Soil sieving separated samples into coarse earth (>2.00mm) and fine earth fractions (< 2.00mm). A loss on ignition (LOI) test was completed on 5.00g fine earth from each sample to determine SOC values. Simple calculations show woody species (Ponderosa, and Juniper) plots having slightly elevated SOC concentrations than shallow rooted species (sagebrush, alfalfa). However, more complex analytical procedures will be completed using R statistical computing that account for multiple variables across all plots. This study has the potential to quantify SOC concentrations of soils that have not previously been analyzed. More importantly, this research could predict changes in SOC within rapidly changing ecosystems like the Chewaucan River Basin.

Exploring Neuronal Cell Ablation & the Social Behavior Network in Zebrafish

Presenter(s): Allison Hoslett

Faculty Mentor(s): Alexandra Tallafuss & Phil Washbourne

Poster 71

Session: Sciences

Research for neurodevelopmental disorders characterized by social deficits, such as Autism Spectrum Disorder, has helped increase the quality of life in individuals and families afflicted by these diagnoses. This research aims to understand the neuronal network underlying social behavior in the developing brains of zebrafish (Danio rerio), an experimental animal model that shares relevant cellular pathways and social behaviors that are conserved between vertebrate animals. The neuronal circuit involved in social behavior is poorly understood. We are using genetic and behavioral research techniques to identify populations of neurons that are necessary to recognize biological motion, an important part of social behavior. We are combining behavioral assays and genetic tools that allow for cell tracking and targeted cell death using the nitroreductase/metronidazole system. After targeted ablation of neurons in different areas of the brain, we measure the social behavior of individual zebrafish larvae. We do this by projecting dots that imitate the presence and movement of another fish, tracking the fish’s reaction with these dots, which is then calculated into a social index. We were able to identify neuronal populations that, after ablation, severely reduce social behavior. Using this approach will allow us to identify a more complete picture of how the social circuit works and which neuronal populations are involved. Unraveling the social circuit will allow early identification and more targeted treatment of patients with neurodevelopmental disorders that are characterized by impairments in typical social behaviors.