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May 21, 2021 Mary Gates Hall

gene outcompete others in an environment containing antibi- SESSION O-1D otics. In doing so, I can determine how this particular gene may evolve when various bacterial hosts exist in a microbial MECHANISMSAND EFFECTS OF community. The results of this experiment will improve our understanding of plasmid biology and the evolution of antibi- GENE EXPRESSION otic resistance genes in diverse communities of bacteria. Session Moderator: Joseph Groom, Chemical Engineering Join Room 9:00 AM to 10:30 AM FROM MINIATURE TO MASSIVE - * Note: Titles in order of presentation. SCIENCE ACROSS ORDERSOF The Effects of Horizontal Gene Transfer on Antibiotic MAGNITUDE Resistance Bailey Marie Werner, Senior, Biology (Molecular, Cellular & Session Moderator: Peter Brodsky, Applied Physics Developmental) Laboratory Mentor: Benjamin Kerr, Biology Join Room Bacteria can inherit genes through two modes of transmis- 9:00 AM to 10:30 AM sion: vertical inheritance, in which a cell receives genes from * Note: Titles in order of presentation. its parent cell during division, or horizontal gene transfer, in which genes are passed laterally between two unrelated cells. Identifying and Estimating Ages of Red Supergiant Stars Extrachromosomal DNA, called plasmids, can be transmit- in the NGC6946 Galaxy ted from a bacterial cell to a neighboring cell of the same or Jared Reid Johnson, Recent Graduate, different species through a form of horizontal gene transfer Mentor: Benjamin Williams, Astronomy known as conjugation. These conjugative plasmids can en- Red Supergiants (RSGs) probe an advanced stage in the evo- code for antibiotic resistance genes which allows a host cell lution of massive stars that is of particular interest in pro- to produce proteins that degrade antibiotics. In an environ- viding chemical and energy feedback into their surrounding ment with these drugs, a host cell with this plasmid would be environments. Using data from the Hubble Space Telescope more likely to survive, compared to a plasmid-free cell, due (HST) and the Spitzer Space Telescope (Spitzer), we identify to the benefits of the antibiotic resistance gene. Additionally, RSG stars in the nearby face-on spiral galaxy NGC6946. Our these antibiotic resistance genes can often acquire mutations goal was to identify RSGs, constrian their ages, compare the which increases the level of antibiotic resistance for the host ages and brightnesses to the existing models, and finally infer cell. However, these acquired mutations may be more ben- an initial mass for the star. Understanding RSGs is an im- eficial (i.e., higher resistance for the host cell) in one bac- portant step in determining which massive stars will explode terial species than the same mutation in another species. In and which will not. NGC6946 has an explosive history with a other words, the effect of mutation on the plasmid-encoded very high supernova rate, this makes the galaxy a great place antibiotic resistance gene may be contingent upon the host to look for RSGs. We found 57 RSG candidates and estimated species. Given that antibiotic resistance genes are often en- their ages by measuring the age of stars in their surrounding coded on conjugative plasmids that are shared among species, environment. Models suggest that 5-26 Million years (Myr) my project is investigating how protein evolution may be af- old RSG stars have masses of 10-30 times the mass of our fected due to plasmid genes existing in multiple bacterial sun. Our candidates returned ages ranging between 5-30 Myr hosts. I performed a series of competitions between three with 24 of the candidates landing in the 10-20 Myr range. bacterial species containing plasmids with versions of an an- Comparing our measured ages and brightnesses to the mod- tibiotic resistance gene to determine which versions of the

Undergraduate Research Program 1 www.uw.edu/undergradresearch els, many of our candidates appear to have properties con- bution of progenitor masses was consistent with mass dis- sistent with the model predictions. However, the brightness tributions measured for massive stars in other galaxies, in- of our candidates spans a larger range of brightness than the cluding our own Milky Way. These new measurements allow models for Spitzer would predict. We also find that four of NGC6946 to be included for the first time in statistical studies our candidates are more consistent with models of two-star of the masses of stars that produce supernovae. (binary) systems, making them good candidates for multiple star systems. SESSION T-1E SESSION O-1J BIOMEDICAL SCIENCES -LAB SCIENCES 1 FROM MINIATURE TO MASSIVE - Session Moderator: Jason Smith, Microbiology SCIENCE ACROSS ORDERSOF Join Room Session Moderator: Peter Brodsky, Applied Physics 9:00 AM to 9:55 AM Laboratory * Note: Titles in order of presentation. Join Room Melanogaster: Effect on Locomotive Function 9:00 AM to 10:30 AM Caroline Read (Caroline) Rawls, Junior, Biology (General) * Note: Titles in order of presentation. Mentor: Daniel Promislow, Department of Lab Medicine & Pathology, University of Washington School of Medicine The Masses of Supernova Remnant Progenitors in NGC Mentor: Ben Harrison, Pathology 6946 Bradley M (Brad) Koplitz, Senior, Astronomy, Physics: My research focuses on ‘tauopathy’—the pathological ef- Comprehensive Physics fects of misfolding of the tau protein—using the fruit fly, UW Honors Program Drosophila melanogaster, as a model system. In particular, Mentor: Benjamin Williams, Astronomy I am interested in how the expression of tau affects loco- motive function. Tau is a protein found in both humans and When massive stars die, they explode in violent spectacles flies that is associated with stabilizing neuronal microtubules. known as supernovae, specifically core-collapse supernovae. However, under certain physiological conditions, human tau These cataclysmic events produce and distribute a large frac- proteins form neurotoxic aggregates in the brain. This neu- tion of the heavy elements in the universe, but the properties ronal damage leads to dementia, a hallmark of Alzheimer’s of the massive stars that produce them have historically been Disease (AD). Aging comes with a multitude of age-related difficult to measure. I have made new measurements con- functional deficits, including decline in locomotor function. straining the masses of stars that have produced core-collapse Some individuals with AD pathology are never diagnosed, supernovae, also known as supernova progenitors. I have however, because the cognitive impairment they experience done this by measuring the ages of stars at the location of is not sufficient for a clinical diagnosis of dementia, the most supernova remnants: the nebulae of excited and enriched gas common symptom of AD. Consequently, it is imperative we left behind by supernovae that have occurred over the past understand AD as more than dementia. I study the climbing 20,000 years. Assuming the progenitor was associated with abilities of transgenic tau and control flies through negative these stars, I am able to estimate the age of the star that ex- geotaxis assays. Negative geotaxis refers to the tendency of ploded. Using theoretical models, I am able to infer the mass flies to move vertically upward when startled. For my project, from this age. I used images taken by the Hubble Space Tele- I am measuring the climbing performance of the flies to see scope to investigate the stars responsible for producing hun- the effects of tau on locomotor function as flies age. I hypoth- dreds of these remnants in the nearby galaxy NGC 6946. In esize that the neurotoxic tau aggregates that form will inter- addition to the remnants of supernovae, this galaxy has hosted fere with neural activity involved in the flies’ motor function, ten observed core-collapse supernovae within the past hun- resulting in decreased climbing performance. This research dred years, leading to it being referred to as the “Fireworks holds an abundance of biomedical implications and a capac- Galaxy”. I was able to constrain the progenitor mass distri- ity to better the lives of many. By using motor function to bution for 175 remnants, eight of the historically observed flag at-risk individuals early in their lives, they have the op- supernovae, as well as the progenitor of the first direct black portunity to participate in preclinical AD clinical trials that hole formation candidate in NGC 6946. I found the distri- may prevent them from developing AD pathology later on.

2 It is important that we, as a scientific community, strive to better understand the effects of aging and tauopathies, as it is SESSION T-3G through this understanding we can provide elderly individuals with care that transforms their quality of life. NEUROSCIENCE 3 Session Moderator: Dylan Hedman, Biochemistry SESSION O-2J Join Room MOLECULAR INSIGHTSTO DISEASE 11:00 AM to 11:50 AM AND REGENERATION * Note: Titles in order of presentation. Session Moderator: Elaheh Karbassi, Mapping and Opioid Receptor Gene < a Expression in Mouse Brain using Fluorescent In Situ href=”https://washington.zoom.us/j/97919059299”target Hybridization =”blank ”>Join Room Fleur Uittenbogaard, Junior, Biology (Physiology) 11:00 AM to 12:30 PM UW Honors Program * Note: Titles in order of presentation. Mentor: Michael Bruchas, Anesthesiology & Pain Medicine Mentor: Nephi Stella, Pharmacology Detection of Glycation and Deglycation Activities in Mentor: Benjamin Land, Pharmacology Maize Organellar DNA Mentor: Anthony English, Pharmacology Emma Bingham, Senior, Biology (Molecular, Cellular & Developmental) ∆9- (THC) is the primary psychoactive Mentor: Diwaker Tripathi, Biology compound found in sativa. The psychoactive and Mentor: Arnold Bendich, Biology cannabimimetic behaviors associated with THC have been DNA glycation is the DNA damage induced by reactive car- well described as being dependent on the partial agonist activ- bonyls (such as methylglyoxal and ) in plants and ity of THC at the endogenous cannabinoid 1 receptor (CB1R). mammals. Glycation damage is quantitatively as important as We are investigating the direct action of THC on the medial oxidative damage. It is one of the major in vivo DNA damage prefrontal cortex (mPFC, a brain region primarily responsi- sources associated with increased mutation frequency, DNA ble for executive function), and the effects of adolescent THC µ strand breaks, and cytotoxicity. In humans, glycation damage exposure on -opioid receptor (MOR) expression in adult pe- may contribute to Parkinson’s disease, cancer, and oxidative riaqueductal grey (PAG, a brain region involved in opioid- stress-induced diseases. Glycation damage in plant organelle mediated pain inhibition). To increase our understanding of (Chloroplasts and Mitochondria) DNA remains poorly under- the cannabimimetic behavioral effects of THC, and its direct stood. We recently showed that the demise of plastid DNA pharmacological action in the brain, it is important to map (ptDNA) and mitochondrial DNA (mtDNA) during maize the neuro-anatomical expression of target proteins. We ex- seedling development is associated with an increase in DNA amined expression patterns of CB1R and MOR in the mPFC damage resulting from oxidative stress caused by reactive and the PAG, respectively. To do this, we utilized a form of in situ oxygen species. As oxidative and glycation stress are closely hybridization, RNAscope. We leveraged RNAscope linked in plants, we hypothesize that glycation might be one by preparing tissue samples from brain regions of interest for of the causes of ptDNA and mtDNA damage during devel- treatment with mRNA-specific probes, allowing us to target opment. Glycation damage can be prevented by the activ- CB1R and MOR mRNA. After a series of washes and incuba- ity of the protein deglycase DJ-1, also known as Parkinson’s tions, these fluorescent probes hybridize to our target mRNAs Disease Protein 7 (PARK7). Our objective is to quantify and allow us to visualize their expression under a confocal glycation lesions in the organelles of maize plant tissues in microscope. Analysis of mRNA expression informs us on the presence and absence of DJ-1. Our approach involves the localization of the CB1R/MOR and known neuron types the quantification of glycation and deglycation in ptDNA within our brain regions of interest. After imaging, we are and mtDNA using PCR analysis and the enzyme-linked im- able to utilize HALO software to analyze the levels of expres- munosorbent assay (ELISA). This research should better un- sion and co-localization of CB1R/MORs with neuronal mark- derstand glycation damage in plant organelles and might lead ers for glutamatergic and GABAergic neuron types. By creat- to insights concerning human pathologies and neurodegener- ing and optimizing a workflow for extraction, preparation, hy- ative disease caused by glycation. bridization, and analysis, we determined CB1R mRNA is pri- marily co-localized with glutamatergic neurons in the mPFC. Moving forward, we are utilizing this RNAscope technique to investigate differential CB1R expression GABA interneuron

3 subpopulations in the mPFC. (Funded by DA051558) gests that classical THC and cannabinoid-dependent behav- iors in mice can feasibly be studied with a more translational model (Funded by DA051558). Optimizing an oral adminis- SESSION T-5F tration model of in mice will enable future re- search on the pharmacology of oral cannabinoid therapeutics. CLINICAL SCIENCES & NEUROSCIENCE Session Moderator: Lily Peterson, Join Room 1:20 PM to 2:10 PM * Note: Titles in order of presentation.

Voluntary Oral Consumption of ∆9-Tetrahydrocannabinol in Mice Triggers Cannabimimetic Behaviors Anna Veronica Elizab (Anna) Slaven, Junior, Psychology Mentor: Anthony English, Pharmacology Mentor: Nephi Stella, Pharmacology Mentor: Michael Bruchas, Anesthesiology and Pain Medicine, Pharmacology, Biochemistry, J WING ROOM 187A Mentor: Benjamin Land, Pharmacology

Cannabis sativa is one of the most widely used drugs in the world. In humans, Cannabis sativa is commonly used to alleviate anxiety and pain, among other things, in med- ical and recreational contexts. In mice, intraperitoneal (i.p.) injections of its primary psychoactive compound, ∆9- tetrahydrocannabinol (THC) produce a characteristic triad of behavioral responses consisting of hypolocomotion, hy- pothermia, and analgesia. However, injections of THC do not accurately represent how humans typically administer THC, which primarily consists of inhalation and oral con- sumption. To better model a typical route of administra- tion used by humans, we developed a voluntary oral con- sumption paradigm in mice whereby THC is formulated in gelatin. Following habituation, mice were given ad libi- tum access to THC gelatin for 2 hours. We measured the triad behaviors immediately following consumption to de- termine whether voluntary oral consumption of THC-gelatin using this paradigm induces acute cannabimimetic behav- iors. Due to the slow pharmacokinetic activity of orally con- sumed THC, we measured triad responses immediately, 1 hour, and 2 hours after consumption. To compare our rela- tive THC-gelatin-induced cannabimimetic behaviors to pub- lished data, we replicated the triad experiment and demon- strated our ability to obtain dose-dependent triad responses by using i.p. injections. At high concentrations (4mg/15mL) of THC-gelatin, cannabimimetic behavioral responses matched those of mice treated with low-dose (3 mg/kg) of THC i.p. injections. From these initial studies we conclude that de- velopment of THC-gelatin formulation triggers characteristic cannabimimetic behavioral effects in mice. These results sug-

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