Biology Commons^™

The Neuronal Calcium Sensor Ncs-1 Regulates The Phosphorylation State And Activity Of The Gα Chaperone And Gef Ric-8a, Daniel Muñoz-Reyes, Levi J. Mcclelland, Sandra Arroyo-Urea, Sonia Sánchez-Yepes, Juan Sabín, Sara Pérez-Suárez, Margarita Menendez, Alicia Mansilla, Javier García-Nafría, Stephen Sprang, Maria Jose Sanchez-Barrena

Biological Sciences Faculty Publications

The neuronal calcium sensor 1 (NCS-1), an EF-hand Ca binding protein, and Ric-8A coregulate synapse number and probability of neurotransmitter release. Recently, the structures of Ric-8A bound to Gα have revealed how Ric-8A phosphorylation promotes Gα recognition and activity as a chaperone and guanine nucleotide exchange factor. However, the molecular mechanism by which NCS-1 regulates Ric-8A activity and its interaction with Gα subunits is not well understood. Given the interest in the NCS-1/Ric-8A complex as a therapeutic target in nervous system disorders, it is necessary to shed light on this molecular mechanism of action at atomic level. We have reconstituted …

The Role Of Serca In Neural Development And Brain Tumors, Hannah M. Christman

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Ion channels are essential for neural function, playing a variety of necessary cellular roles including excitability, maintaining ion gradients, and volume control. While the role of ion channels in neurons is well-defined, much less is known about excitability in neural progenitor cells. Recently it has emerged that these neural precursors may be affected by channelopathies, indicating a critical role of ion channels in neural development. Using the model system Drosophila melanogaster (fruit fly), I investigated the role of the ion channel SERCA (sarco/endoplasmic reticulum Ca2+ATPase). SERCA is a vital calcium ion pump located on the wall of the endoplasmic reticulum, …

Determining Species-Specific False-Positive Rates Using Visual And Auditory Cues: A Case Study With Sagebrush Steppe Songbirds, Amelia K. Evavold

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Errors in wildlife field data threaten to bias resulting abundance and occupancy estimates if not properly accounted for or minimized. Methods to account for false-positive errors in wildlife data have not been as thoroughly developed as those for false-negative errors despite false-positives being present across diverse wildlife taxa and study systems. The calibration method to account for false-positives involves assessing the field detection method to determine how often false-positive errors occur in the field data. Rates can then be incorporated into estimations based on the field data to improve estimation accuracy. This study presents an application of the calibration approach …

Application Of Sulfur Sad To Small Crystals With A Large Asymmetric Unit And Anomalous Substructure, Tung Chung Mou, Baisen Zeng, Tzanko I. Doukov, Stephen R. Sprang

Biological Sciences Faculty Publications

The application of sulfur single-wavelength anomalous dispersion (S-SAD) to determine the crystal structures of macromolecules can be challenging if the asymmetric unit is large, the crystals are small, the size of the anomalously scattering sulfur structure is large and the resolution at which the anomalous signals can be accurately measured is modest. Here, as a study of such a case, approaches to the SAD phasing of orthorhombic Ric-8A crystals are described. The structure of Ric-8A was published with only a brief description of the phasing process [Zeng et al. (2019), Structure, 27, 1137-1141]. Here, alternative approaches to determining the 40-atom …

Feeling The Burn: Assessing The Effects Of Fire Severity On Elk Nutritional Resources And Resource Selection, Lauren Ashley Snobl

Graduate Student Theses, Dissertations, & Professional Papers

Wildfires in the western United States have been increasing in size and severity over the last several decades, and climate forecasts suggest a continued increase in wildfire activity in the future. Large-scale wildfires often burn in a mosaic-like pattern of varying fire severity creating a heterogenous landscape with concomitant effects on vegetation communities. By changing vegetative structure, fire severity potentially alters the availability and distribution of key resources for wildlife such as food and cover, ultimately influencing habitat use. However, the impact of fire on wildlife has frequently been treated as binary (i.e., burned vs unburned), and a deeper understanding …

Evolutionary Dynamics And Structural Consequences Of De Novo Beneficial Mutations And Mutant Lineages Arising In A Constant Environment, Margie Kinnersley, Katja Schwartz, Dong Dong Yang, Gavin Sherlock, Frank Rosenzweig

Biological Sciences Faculty Publications

Background: Microbial evolution experiments can be used to study the tempo and dynamics of evolutionary change in asexual populations, founded from single clones and growing into large populations with multiple clonal lineages. High-throughput sequencing can be used to catalog de novo mutations as potential targets of selection, determine in which lineages they arise, and track the fates of those lineages. Here, we describe a long-term experimental evolution study to identify targets of selection and to determine when, where, and how often those targets are hit. Results: We experimentally evolved replicate Escherichia coli populations that originated from a mutator/nonsense suppressor ancestor …

A Reintroduction Retrospective: Comparative Fisher (Pekania Pennanti) Survival And Prey Habitat Use In The Cascade Mountains Of Washington State, Tanner S.T. Humphries

Graduate Student Theses, Dissertations, & Professional Papers

Increasing human impacts on biodiversity highlight the global need for ecological restoration. For many wildlife species, reintroduction is necessary to re-establish populations in parts of their historic range where they have been extirpated. Reintroduction efforts are commonly used to help restore ecosystem integrity, but are often expensive, time consuming, and unsuccessful at generating self-sustaining populations. Thus, a more complete understanding of the factors affecting restoration success is important for ensuring successful outcomes and responsible stewardship. Fishers (Pekania pennanti) are one of the most commonly reintroduced carnivores in North America, but the success of such efforts is highly variable, …

The Structure Of The Cysteine-Rich Region From Human Histone-Lysine N-Methyltransferase Ehmt2 (G9a), Keshia M. Kerchner, Tung-Chung Mou, Yizhi Sun, Domniţa-Valeria Rusnac, Stephen R. Sprang, Klára Briknarová

Biological Sciences Faculty Publications

Euchromatic histone-lysine N-methyltransferase 1 (EHMT1; G9a-like protein; GLP) and euchromatic histone-lysine N-methyltransferase 2 (EHMT2; G9a) are protein lysine methyltransferases that regulate gene expression and are essential for development and the ability of organisms to change and adapt. In addition to ankyrin repeats and the catalytic SET domain, the EHMT proteins contain a unique cysteine-rich region (CRR) that mediates protein-protein interactions and recruitment of the methyltransferases to specific sites in chromatin. We have determined the structure of the CRR from human EHMT2 by X-ray crystallography and show that the CRR adopts an unusual compact fold with four bound zinc atoms. The …

Effects Of Wolf And Grizzly Bear Recovery On Cougars In A Multi-Use System, Jennifer A. Feltner

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

Differential Diagnosis Of Abnormal Muscle Gross Anatomy Of A Male Cadaver, Audrey V. Broffman, Carley R. Carpenter

Undergraduate Theses, Professional Papers, and Capstone Artifacts

The ability of healthcare providers to carefully consider all presentations of illness and injury, draw upon research and knowledge to develop a list of potential diagnoses, and further investigate systems expected to be impacted by these diagnoses, is crucial for accurate identification of a condition and subsequent treatment plans to improve the welfare of patients. In order to determine a possible cause for unusual anatomic changes in multiple regions of the male cadaver used in the University of Montana’s Anatomy and Physiology lab, we performed a differential diagnosis.This research is exempt from IRB approval because the individual is no longer …

Novel Small Rnas Expressed By Bartonella Bacilliformis Under Multiple Conditions Reveal Potential Mechanisms For Persistence In The Sand Fly Vector And Human Host, Shaun Wachter, Linda D. Hicks, Rahul Raghavan, Michael F. Minnick

Biological Sciences Faculty Publications

Bartonella bacilliformis, the etiological agent of Carrión's disease, is a Gram-negative, facultative intracellular alphaproteobacterium. Carrión's disease is an emerging but neglected tropical illness endemic to Peru, Colombia, and Ecuador. B. bacilliformis is spread between humans through the bite of female phlebotomine sand flies. As a result, the pathogen encounters significant and repeated environmental shifts during its life cycle, including changes in pH and temperature. In most bacteria, small non-coding RNAs (sRNAs) serve as effectors that may post-transcriptionally regulate the stress response to such changes. However, sRNAs have not been characterized in B. bacilliformis, to date. We therefore performed total RNA-sequencing …

Matrices (Re)Loaded: Durability, Viability, And Fermentative Capacity Of Yeast Encapsulated In Beads Of Different Composition During Long-Term Fed-Batch Culture, Jordan Gulli, Peter Yunker, Frank Rosenzweig

Biological Sciences Faculty Publications

Encapsulated microbes have been used for decades to produce commodities ranging from methyl ketone to beer. Encapsulated cells undergo limited replication, which enables them to more efficiently convert substrate to product than planktonic cells and which contributes to their stress resistance. To determine how encapsulated yeast supports long-term, repeated fed-batch ethanologenic fermentation, and whether different matrices influence that process, fermentation and indicators of matrix durability and cell viability were monitored in high-dextrose, fed-batch culture over 7 weeks. At most timepoints, ethanol yield (g/g) in encapsulated cultures exceeded that in planktonic cultures. And frequently, ethanol yield differed among the four matrices …

Human Vascular Endothelial Cells Express Epithelial Growth Factor In Response To Infection By Bartonella Bacilliformis, Linda D. Hicks, Michael F. Minnick

Biological Sciences Faculty Publications

Bartonella are Gram-negative bacterial pathogens that trigger pathological angiogenesis during infection of humans. Bartonella bacilliformis (Bb) is a neglected tropical agent endemic to South America, where it causes Carrión's disease. Little is known about Bb's virulence determinants or how the pathogen elicits hyperproliferation of the vasculature, culminating in Peruvian warts (verruga peruana) of the skin. In this study, we determined that active infection of human umbilical vein endothelial cells (HUVECs) by live Bb induced host cell secretion of epidermal growth factor (EGF) using ELISA. Killed bacteria or lysates of various Bb strains did not cause EGF production, suggesting that an …

Structure Of The G Protein Chaperone And Guanine Nucleotide Exchange Factor Ric-8a Bound To Gαi1, Levi J. Mcclelland, Kaiming Zhang, Tung-Chung Mou, Jake Johnston, Cindee Yates-Hansen, Shanshan Li, Celestine J. Thomas, Tzanko I. Doukov, Sarah Triest, Alexandre Wohlkonig, Gregory G. Tall, Jan Steyaert, Wah Chiu, Stephen R. Sprang

Biological Sciences Faculty Publications

Ric-8A is a cytosolic Guanine Nucleotide exchange Factor (GEF) that activates heterotrimeric G protein alpha subunits (Gα) and serves as an essential Gα chaperone. Mechanisms by which Ric-8A catalyzes these activities, which are stimulated by Casein Kinase II phosphorylation, are unknown. We report the structure of the nanobody-stabilized complex of nucleotide-free Gα bound to phosphorylated Ric-8A at near atomic resolution by cryo-electron microscopy and X-ray crystallography. The mechanism of Ric-8A GEF activity differs considerably from that employed by G protein-coupled receptors at the plasma membrane. Ric-8A engages a specific conformation of Gα at multiple interfaces to form a complex that …

Encapsulation Enhances Protoplast Fusant Stability, Jordan Gulli, Eugene Kroll, Frank Rosenzweig

Biological Sciences Faculty Publications

A barrier to cost-efficient biomanufacturing is the instability of engineered genetic elements, such as plasmids. Instability can also manifest at the whole-genome level, when fungal dikaryons revert to parental species due to nuclear segregation during cell division. Here, we show that by encapsulating Saccharomyces cerevisiae-Pichia stipitis dikaryons in an alginate matrix, we can limit cell division and preserve their expanded metabolic capabilities. As a proxy to cellulosic ethanol production, we tested the capacity of such cells to carry out ethanologenic fermentation of glucose and xylose, examining substrate use, ploidy, and cell viability in relation to planktonic fusants, as well as …

Gene Duplication And Deletion, Not Horizontal Transfer, Drove Intra-Species Mosaicism Of Bartonella Henselae, Rachana Banerjee, Oshina Shine, Vyshakh Rajachandran, Govind Krishnadas, Michael F. Minnick, Sandip Paul, Sujay Chattopadhyay

Biological Sciences Faculty Publications

Bartonella henselae is a facultative intracellular pathogen that occurs worldwide and is responsible primarily for cat-scratch disease in young people and bacillary angiomatosis in immunocompromised patients. The principal source of genome-level diversity that contributes to B. henselae's host-adaptive features is thought to be horizontal gene transfer events. However, our analyses did not reveal the acquisition of horizontally-transferred islands in B. henselae after its divergence from other Bartonella. Rather, diversity in gene content and genome size was apparently acquired through two alternative mechanisms, including deletion and, more predominantly, duplication of genes. Interestingly, a majority of these events occurred in regions that …

Characterizing The Requirements For The Matricellular Protein, Dccn, In Nervous System Function, Elizabeth L. Catudio Garrett

Graduate Student Theses, Dissertations, & Professional Papers

The brain is organized as a complex network of specialized neurons that communicate via a combination of electrical and chemical signals. Our brains function to generate movement, control organ function, or direct complex behaviors; all of which requires the ability to regulate the flow of communication between circuits and networks. Work in this thesis addresses two areas of neuron communication: first, how does the release of more than one neurotransmitter from a single neuron impact behavior, and second, are matricellular proteins (MCPs) key contributors to synaptic transmission and neuron function? The conserved CCN family of MCPs have a …

Metabolic And Cardiovascular Marker Alterations During Critical Training In Wildland Firefighters, Shae Gurney

Graduate Student Theses, Dissertations, & Professional Papers

Introduction: Wildland firefighters (WLFFs) are confronted with numerous physical and mental stressors. Pre-fire season includes an intense 2-week critical training (CT) period; a preparatory phase of multiple activities that can result in injury, illness, and rhabdomyolysis. The purpose of this study was to identify physiologic changes in metabolic, inflammatory, and oxidative stress biomarkers during 2 weeks of CT in WLFFs.

Methods: Eighteen male (29.4 ± 1.1 yr, 182.1 ± 1.6 cm) and three female (26.7  2.6 yr, 169.5  4.2 cm) participants were recruited from a Type I interagency hotshot crew and monitored over their 2-week CT. Fitness was …

Heat For The Masses: Thermal Ecology Of The Western Tent Caterpillar, Victoria Dahlhoff

Graduate Student Theses, Dissertations, & Professional Papers

A unique feature of some gregarious, colonial insects is their ability to create external structures that alter environmental conditions for the entire (often family) group. A combination of physical alteration of local microhabitats and behavioral thermoregulation allows many of these animals to actively control their body temperatures, which allows them to regulate energy use and metabolism in variable thermal environments. Here I describe mechanisms of microhabitat modification and thermal regulation in the western tent caterpillar, Malacosoma californicum pluviale. Tent caterpillars build communal silk tents, whose temperatures can rise substantially above ambient air temperature. I experimentally manipulated colony sizes and examined …

The Evolution Of Dragons, Laura J. Mayfield

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Dragons have been depicted in human art as early as 4500 BCE. For centuries, these fantasy creatures have inspired countless folk and fantasy tales, as well as appearing in the art of different cultures around the world. Now there are thousands of different depictions of these huge, flying, fire-breathing lizards, but are any of them possible? In this study, I reference peer-reviewed scientific articles, phylogenetic analysis, and paleoart studies to create biologically-sound dragons. Basing the dragon lineage on a real branch of webbed-winged scansoriopterygids—an extinct family of climbing and gliding maniraptoran dinosaurs—I explored the possible wing-structure, fire-breathing abilities, and effects …

A Csra-Binding, Trans-Acting Srna Of Coxiella Burnetii Is Necessary For Optimal Intracellular Growth And Vacuole Formation During Early Infection Of Host Cells, Shaun Wachter, Matteo Bonazzi, Kyle Shifflett, Abraham S. Moses, Rahul Raghavan, Michael F. Minnick

Biological Sciences Faculty Publications

Coxiella burnetii is an obligate intracellular gammaproteobacterium and zoonotic agent of Q fever. We previously identified 15 small noncoding RNAs (sRNAs) of C. burnetii. One of them, CbsR12 (Coxiella burnetii small RNA 12), is highly transcribed during axenic growth and becomes more prominent during infection of cultured mammalian cells. Secondary structure predictions of CbsR12 revealed four putative CsrA-binding sites in stem loops with consensus AGGA/ANGGA motifs. We subsequently determined that CbsR12 binds to recombinant C. burnetii CsrA-2, but not CsrA-1, proteins in vitro. Moreover, through a combination of in vitro and cell culture assays, we identified several in trans mRNA …

Diverse Conditions Support Near-Zero Growth In Yeast: Implications For The Study Of Cell Lifespan, Jordan Gulli, Emily Cook, Eugene Kroll, Adam Rosebrock, Amy Caudy, Frank Rosenzweig

Biological Sciences Faculty Publications

Baker’s yeast has a finite lifespan and ages in two ways: a mother cell can only divide so many times (its replicative lifespan), and a non-dividing cell can only live so long (its chronological lifespan). Wild and laboratory yeast strains exhibit natural variation for each type of lifespan, and the genetic basis for this variation has been generalized to other eukaryotes, including met-azoans. To date, yeast chronological lifespan has chiefly been studied in relation to the rate and mode of functional decline among non-dividing cells in nutrient-depleted batch culture. However, this culture method does not accurately capture two major classes …

Structure, Function, And Dynamics Of The Gα Binding Domain Of Ric-8a, Baisen Zeng, Tung-Chung Mou, Tzanko I. Doukov, Andrea Steiner, Wenxi Yu, Makaia Papasergi-Scott, Gregory G. Tall, Franz Hagn, Stephen R. Sprang

Biological Sciences Faculty Publications

Ric-8A is a 530-amino acid cytoplasmic molecular chaperone and guanine nucleotide exchange factor (GEF) for i, q, and 12/13 classes of heterortrimeric G protein alpha subunits (Gα). We report the 2.2-Å crystal structure of the Ric-8A Gα-binding domain with GEF activity, residues 1-452, and is phosphorylated at Ser435 and Thr440. Residues 1-429 adopt a superhelical fold comprised of Armadillo (ARM) and HEAT repeats, and the C terminus is disordered. One of the phosphorylated residues potentially binds to a basic cluster in an ARM motif. Amino acid sequence conservation and published hydrogen-deuterium exchange data indicate repeats 3 through 6 to be …

De Novo Origins Of Multicellularity In Response To Predation, Matthew D. Herron, Joshua M. Borin, Jacob C. Boswell, Jillian Walker, I. Chen Kimberly Chen, Charles A. Knox, Margrethe Boyd, Frank Rosenzweig, William C. Ratcliff

Biological Sciences Faculty Publications

The transition from unicellular to multicellular life was one of a few major events in the history of life that created new opportunities for more complex biological systems to evolve. Predation is hypothesized as one selective pressure that may have driven the evolution of multicellularity. Here we show that de novo origins of simple multicellularity can evolve in response to predation. We subjected outcrossed populations of the unicellular green alga Chlamydomonas reinhardtii to selection by the filter-feeding predator Paramecium tetraurelia. Two of five experimental populations evolved multicellular structures not observed in unselected control populations within ~750 asexual generations. Considerable variation …

Spatiotemporal Dynamics Of Nitrogen And Carbon Biogeochemistry In A Wetland-Stream Sequence, Patrick E. Hurley

Graduate Student Theses, Dissertations, & Professional Papers

Studies of aquatic ecosystems often segregate streams from the influential ponds, lakes, and wetland zones that act as important transitions between terrestrial and fluvial systems. Across the aquatic landscape, these zones interact to form linked ecosystems that function as discrete nutrient processing domains, shifting biogeochemical signals due to spatial and temporal variability in hydrologic and biologic controls. Using a mass-balance approach, we profiled nutrient dynamics along a 23-km wetland-stream sequence over three seasons. Hydrologic, morphologic, and biologic conditions, as well as landscape attributes, were quantified to determine potential controls on biogeochemical cycling in a tributary of the Upper Clark Fork …

Methods For Estimating Mountain Goat Occupancy And Abundance, Molly Mcdevitt

Graduate Student Theses, Dissertations, & Professional Papers

Abundance and occupancy are two parameters of central interest to the field of ecology. Furthermore, accurate (both precise and unbiased) estimates are key pieces to the puzzle of effective wildlife management decision-making. While there exist a variety of sampling techniques and statistical models for effectively estimating population parameters for frequently encountered and large mammals, methods for sampling unmarked and rare species are few and far between. The first step to acquiring usable parameter estimates is through the use of sampling theory and incorporation of probabilistic sampling designs to collect count-data and occurrence-data. Often, it is assumed that probabilistic sampling designs …

Population And Breeding Ecology Of Sagebrush Steppe Songbirds, Kayla Ann Ruth

Graduate Student Theses, Dissertations, & Professional Papers

Sagebrush steppe is one of the most threatened ecosystems in North America. Domestic livestock grazing is the dominant land use of sagebrush steppe across the west. Rest-rotation grazing systems can be a conservation management tool, most recently, by the Natural Resource Conservation Service - Sage Grouse Initiative (SGI). The goal of SGI is to encourage private landowners to use a livestock grazing regime that maintains or improves habitat for greater sage-grouse (Centrocercus urophasianus), as well as improve rangeland productivity. Songbirds are biological indicators that can assess the health of sagebrush steppe. Avian adult density estimates are often used …

Canis Lupus (Gray Wolf) Pup Survival In Yellowstone National Park, Anne Marie Jehle

Undergraduate Theses, Professional Papers, and Capstone Artifacts

The aim of this study was to describe gray wolf (Canis lupus) pup survival rates throughout the summer months in Yellowstone National Park. Understanding pup survival has implications for trends in pack and population age structure, cooperative breeding ecology and other breeding tendencies, social hierarchies, and population fitness, among other elements of species-specific population ecology. A general understanding of trends in pup survival is also relevant to state and federal land that allow gray wolf harvest. Understanding such trends and survival ecology gives managers and biologists the opportunity to evaluate gray wolf populations at a more comprehensive level and implement …

Atypical Activation Of The G Protein Gα By The Oncogenic Mutation Q209p, Marcin Maziarz, Anthony Leyme, Arthur Marivin, Alex Luebbers, Prachi P. Patel, Zhe Chen, Stephen R. Sprang, Mikel Garcia-Marcos

Biological Sciences Faculty Publications

The causative role of G protein-coupled receptor (GPCR) pathway mutations in uveal melanoma (UM) has been well-established. Nearly all UMs bear an activating mutation in a GPCR pathway mediated by G proteins of the G family, driving tumor initiation and possibly metastatic progression. Thus, targeting this pathway holds therapeutic promise for managing UM. However, direct targeting of oncogenic Gα mutants, present in ∼90% of UMs, is complicated by the belief that these mutants structurally resemble active Gα WT. This notion is solidly founded on previous studies characterizing Gα mutants in which a conserved catalytic glutamine (Gln-209 in Gα) is replaced …

Genetics Of A De Novo Origin Of Undifferentiated Multicellularity, Matthew D. Herron, William C. Ratcliff, Jacob Boswell, Frank Rosenzweig

Biological Sciences Faculty Publications

The evolution of multicellularity was a major transition in evolution and set the stage for unprecedented increases in complexity, especially in land plants and animals. Here, we explore the genetics underlying a de novo origin of multicellularity in a microbial evolution experiment carried out on the green alga Chlamydomonas reinhardtii. We show that large-scale changes in gene expression underlie the transition to a multicellular life cycle. Among these, changes to genes involved in cell cycle and reproductive processes were overrepresented, as were changes to C. reinhardtii-specific and volvocine-specific genes. These results suggest that the genetic basis for the experimental evolution …