Biology Commons^™

Identifying Sources Of Antibiotic Resistance Genes In The Environment Using The Microbial Find, Inform, And Test Framework, Corinne Wiesner-Friedman, Rachelle E. Beattie, Jill R. Stewart, Krassimira R. Hristova, Marc L. Serre

Biological Sciences Faculty Research and Publications

Introduction: Antimicrobial resistance (AMR) is an increasing public health concern for humans, animals, and the environment. However, the contributions of spatially distributed sources of AMR in the environment are not well defined.

Methods: To identify the sources of environmental AMR, the novel microbial Find, Inform, and Test (FIT) model was applied to a panel of five antibiotic resistance-associated genes (ARGs), namely, erm(B), tet(W), qnrA, sul1, and intI1, quantified from riverbed sediment and surface water from a mixed-use region.

Results: A one standard deviation increase in the modeled contributions of elevated AMR from bovine sources or land-applied waste sources [land application …

The Revised Reference Genome Of The Leopard Gecko (Eublepharis Macularius) Provides Insight Into The Considerations Of Genome Phasing And Assembly, Brendan J. Pinto, Tony Gamble, Chase H. Smith, Shannon E. Keating, Justin C. Havird, Ylenia Chiari

Biological Sciences Faculty Research and Publications

Genomic resources across squamate reptiles (lizards and snakes) have lagged behind other vertebrate systems and high-quality reference genomes remain scarce. Of the 23 chromosome-scale reference genomes across the order, only 12 of the ~60 squamate families are represented. Within geckos (infraorder Gekkota), a species-rich clade of lizards, chromosome-level genomes are exceptionally sparse representing only two of the seven extant families. Using the latest advances in genome sequencing and assembly methods, we generated one of the highest-quality squamate genomes to date for the leopard gecko, Eublepharis macularius (Eublepharidae). We compared this assembly to the previous, short-read only, E. macularius reference genome …

A Lizard Is Never Late: Squamate Genomics As A Recent Catalyst For Understanding Sex Chromosome And Microchromosome Evolution, Brendan J. Pinto, Tony Gamble, Chase H. Smith, Melissa A. Wilson

Biological Sciences Faculty Research and Publications

In 2011, the first high-quality genome assembly of a squamate reptile (lizard or snake) was published for the green anole. Dozens of genome assemblies were subsequently published over the next decade, yet these assemblies were largely inadequate for answering fundamental questions regarding genome evolution in squamates due to their lack of contiguity or annotation. As the “genomics age” was beginning to hit its stride in many organismal study systems, progress in squamates was largely stagnant following the publication of the green anole genome. In fact, zero high-quality (chromosome-level) squamate genomes were published between the years 2012 and 2017. However, since …

A Trait-Based Approach To Explain Plant Coexistence In Tropical Forests, Felipe Nery Arantes Mello

Dissertations (1934 -)

Ecology seeks to explain the mechanisms that allow multiple species to coexist in the same habitat without one species outcompeting or driving others to extinction. Niche differentiation is a mechanism that has been proposed to allow species to coexist through specialization on different resources or habitats, which reduces competition and the probability of competitive exclusion. Species can reduce competition by using different combinations of resources and thus partitioning available resources in time and space. Differences in resource use is hypothesized to be influenced by species’ morphological and physiological adaptations, known as functional traits. Links between functional traits and abiotic factors …

Improving Cold Tolerance Of Asian Rice Through Plant Growth Promoting Bacteria And Rice Gene Manipulation: Mechanisms Of Pseudomonas Mosselli And Osmads27, Nasim Maghboli Balasjin

Dissertations (1934 -)

It is estimated that by the year 2050, the human population will extend to 9.7 billion and therefore the demand for food will increase. It is important to find ways to maintain production of critical crops, like rice, to match the demand. Climate change affects crop productivity as it is the reason for extreme warm or cold weather fluctuations. Asian rice (Oryza sativa L.) generally is grown in tropical and subtropical regions and thus, is sensitive to cold temperatures. This study hypothesized two strategies could improve growth and cold tolerance of rice plants: (1) use of plant growth promoting bacteria …

Breathing Around The Clock: Novel Circadian And Light-Driven Mechanisms That Govern Daily Breathing Behavior In Mice, Aaron Andrew Jones

Dissertations (1934 -)

Breathing, like many physiological functions, exhibits a daily rhythm in mammals that coincides with periods of wakefulness and increased metabolic activity. Dysregulation of daily breathing rhythms has been implicated in a variety of respiratory diseases with time-specific symptomatology including sleep apnea, asthma, chronic pulmonary disease, sudden unexpected death in epilepsy, and COVID-19. While the daily rhythm in breathing is regulated by the endogenous circadian clock in the brain, the underlying physiological and cellular mechanisms modulating daily breathing behavior remain largely unknown. Light is the most potent synchronizer of the circadian system in mammals and is likely the principal driver of …

The N-Terminal Region Of Yeast Mitoribosomal Mrp7/Bl27m Protein Serves To Optimize Translation Of Nascent Chains Competent For Oxphos Complex Assembly, Jessica M. Anderson, Jodie M. Box, Rosemary A. Stuart

Biological Sciences Faculty Research and Publications

The extreme N-terminal residues of the mitochondrial ribosomal bL27m proteins reside within the ribosomal peptidyl transferase center (PTC) and are conserved from their bacterial ancestors. Mutation or truncation of the N-terminal region of the yeast Mrp7/bL27m protein did not inhibit protein synthesis but significantly impacted the efficacy of the mitochondrial translational process with respect to yielding proteins competent to assemble into functional oxidative phosphorylation enzymes. The requirement for the N-terminal residues of Mrp7/bL27m to support normal mitotranslation was more apparent under respiratory growth. We demonstrate that the N-terminal region of Mrp7/bL27m impacts the environment of the PTC and speculate the …

Figures 1 And S3, Tayler D. Sheahan, Amanpreet Grewal, Laura E. Korthauer, Edward M. Blumenthal

Sheahan 2023

Confocal Z-series .nd2 files (Nikon NIS) showing GFP fluorescence from dissected egg chambers. These files were used to create the maximum intensity projections displayed in figure 1 (UAS-GFPnls drd-gal4 stage 10B and 14 10.27.16.nd2) and figure S3 (UAS-GFPnls drd-gal4 stage 14 7.16.21.nd2 and UAS-GFPnls control stage 14 7.16.21.nd2). Files with “UAS-GFPnls drd-gal4” were experimental samples containing both the drd-GAL4 and UAS-GFP.nls transgenes, while files with “UAS-GFPnls control” were controls lacking the drd-GAL4 transgene. The “10.27.16” and “7.16.21” file sets were imaged on different days with different settings, so image intensities should not be compared between the two file sets.

Nuclear And Cytoplasmic Spatial Protein Quality Control Is Coordinated By Nuclear–Vacuolar Junctions And Perinuclear Escrt, Emily M. Sontag, Fabián Morales-Polanco, Jian-Hua Chen, Gerry Mcdermott, Patrick T. Dolan, Dan Gestaut, Mark A. Le Gros, Carolyn Larabell, Judith Frydman

Biological Sciences Faculty Research and Publications

Effective protein quality control (PQC), essential for cellular health, relies on spatial sequestration of misfolded proteins into defined inclusions. Here we reveal the coordination of nuclear and cytoplasmic spatial PQC. Cytoplasmic misfolded proteins concentrate in a cytoplasmic juxtanuclear quality control compartment, while nuclear misfolded proteins sequester into an intranuclear quality control compartment (INQ). Particle tracking reveals that INQ and the juxtanuclear quality control compartment converge to face each other across the nuclear envelope at a site proximal to the nuclear–vacuolar junction marked by perinuclear ESCRT-II/III protein Chm7. Strikingly, convergence at nuclear–vacuolar junction contacts facilitates VPS4-dependent vacuolar clearance of misfolded cytoplasmic …

Postnatal Developmental Trends In Membrane Excitability And Bk Channel Function In The Rodent Hippocampus, Michael S. Hunsberger

Dissertations (1934 -)

This dissertation outlines the postnatal development of excitability as well as expression and function of BK potassium channels in hippocampal neurons. I used patch clamp electrophysiology to measure how neuronal action potential waveforms and action potential firing frequencies change in early development, and how pharmacological blockade of BK channels affects these properties in hippocampal neurons. I also describe how the protein expression of the BK channel pore-forming α subunit and mRNA expression of different variants of the pore forming α subunit and auxiliary beta-4 subunit changes with development. I demonstrate in both cultured rat hippocampal neurons across the first seven …

Evidence That The Inner Nuclear Membrane Is A Functional Β1-Adrenergic Receptor Signaling Platform In Astrocytes, Kelsey Benton

Dissertations (1934 -)

The noradrenergic system exerts powerful modulatory influences over fundamental brain processes including attention, arousal, learning, and memory by activating adrenergic receptors on neuronal and glial cells. In addition to triggering rapid, transient changes in cellular physiology that drive short-term behavioral actions, these G-protein-coupled receptors also initiate delayed, long-lasting changes in cellular function by regulating gene expression. For example, in astrocytes, norepinephrine-induced activation of β-adrenergic receptors (β-ARs) rapidly induces glucose mobilization from glycogen stores, while simultaneously initiating delayed changes in the expression of glycogen storage genes. Regulation of gene expression requires adrenergic receptor-initiated intracellular signals to reach the nuclear compartment. To …

Altered Motivation & Dopamine Subcircuit Plasticity Unique To Sex During Protracted Opioid Withdrawal, Devan Marc Gomez

Dissertations (1934 -)

Opioid use disorder (OUD) is associated with enduring psychological withdrawal symptoms believed to contribute to drug abuse. Amongst these are shifts in motivational states, wherein pursuit of drug consumption exceeds that of non-drug rewards, reinforcing escalated opioid use and relapse vulnerability. A critical regulator of behavioral reinforcement, the mesoaccumbal dopamine system is thought to be both necessary and sufficient for opioid motivation. However, previous research into its involvement in opioid withdrawal has been limited to acute rather than protracted timepoints, global neuroadaptations rather than those in subcircuits, and overwhelmingly focused on males over females. Using a rodent model of self-administration …

Targeted Mapping Of Oryza Sativa Chilling Tolerance Candidate Genes Using Multiple Stress-Relevant Quantitative Traits, Naoki Simon Shimoyama

Dissertations (1934 -)

Developing chilling tolerant accessions of domesticated Asian rice is a potential source of significant crop improvement to address the needs of a growing global population. The uniquely chilling sensitive nature of the tropically originating Oryza sativa make it the most important staple crop that could gain the maximum benefit from improved tolerance to low temperature stress. However, mechanisms underlying this complex trait are not fully understood. Oryza sativa has two major varietal groups with different levels of chilling tolerance, JAPONICA and INDICA, providing an ideal tool to investigate mechanistic differences in the chilling stress tolerance responses within this important crop …

Phase Separation In Biology And Disease; Current Perspectives And Open Questions, Steven Boeynaems, Shasha Chong, Jörg Gsponer, Liam Holt, Dragomir Milovanovic, Diana M. Mitrea, Oliver Mueller-Cajar, Bede Portz, John F. Reilly, Christopher D. Reinkemeier, Benjamin R. Sabari, Serena Sanulli, James Shorter, Emily M. Sontag, Lucia Strader, Jeanne Stachowiak, Stephanie C. Weber, Michael R. White, Huaiying Zhang, Markus Zweckstetter, Shana Elbaum-Garfinkle, Richard Kriwacki

Biological Sciences Faculty Research and Publications

In the past almost 15 years, we witnessed the birth of a new scientific field focused on the existence, formation, biological functions, and disease associations of membraneless bodies in cells, now referred to as biomolecular condensates. Pioneering studies from several laboratories supported a model wherein biomolecular condensates associated with diverse biological processes form through the process of phase separation. These and other findings that followed have revolutionized our understanding of how biomolecules are organized in space and time within cells to perform myriad biological functions, including cell fate determination, signal transduction, endocytosis, regulation of gene expression and protein translation, and …

Hyperdontia In The Paraguayan Martha's Marked Gecko (Homonota Marthae: Phyllodactylidae: Squamata), Juan D. Daza, Emma C. Krakoski, Tony Gamble, Aaron M. Bauer

Biological Sciences Faculty Research and Publications

No abstract provided.

The Role Of Preproglucagon Peptides In Regulating Β-Cell Morphology And Responses To Streptozotocin-Induced Diabetes, Deanna M. Arble, Chelsea R. Hutch, Hannah Hafner, Daria Stelmak, Kyle Leix, Joyce Sorrell, Joshua W. Pressler, Brigid Gregg, Darleen A. Sandoval

Biological Sciences Faculty Research and Publications

Insulin secretion from β-cells is tightly regulated by local signaling from preproglucagon (Gcg) products from neighboring α-cells. Physiological paracrine signaling within the microenvironment of the β-cell is altered after metabolic stress, such as high-fat diet or the β-cell toxin, streptozotocin (STZ). Here, we examined the role and source of Gcg peptides in β-cell function and in response to STZ-induced hyperglycemia. We used whole body Gcg null (Gcg^Null) mice and mice with Gcg expression either specifically within the pancreas (Gcg^ΔPanc) or the intestine (Gcg^ΔIntest). With lower doses of STZ exposure, insulin levels were …

Figure 1, Marquette University, Lisa N. Petrella

Mikeworth 2023

No abstract provided.

Figure 2, Marquette University, Lisa N. Petrella

Mikeworth 2023

No abstract provided.

Figure 5, Marquette University, Lisa Petrella

Mikeworth 2023

No abstract provided.

Figure 4, Marquette University, Lisa Petrella

Mikeworth 2023

No abstract provided.

Figure 3, Marquette University, Lisa Petrella

Mikeworth 2023

No abstract provided.

Figure S2, Marquette University, Lisa Petrella

Mikeworth 2023

No abstract provided.

Figure S1, Marquette University, Lisa Petrella

Mikeworth 2023

No abstract provided.

Mycorrhizal Feedbacks Influence Global Forest Structure And Diversity, Camille S. Delavaux, Joseph A. Lamanna, Jonathan A. Myers, Richard P. Phillips

Biological Sciences Faculty Research and Publications

One mechanism proposed to explain high species diversity in tropical systems is strong negative conspecific density dependence (CDD), which reduces recruitment of juveniles in proximity to conspecific adult plants. Although evidence shows that plant-specific soil pathogens can drive negative CDD, trees also form key mutualisms with mycorrhizal fungi, which may counteract these effects. Across 43 large-scale forest plots worldwide, we tested whether ectomycorrhizal tree species exhibit weaker negative CDD than arbuscular mycorrhizal tree species. We further tested for conmycorrhizal density dependence (CMDD) to test for benefit from shared mutualists. We found that the strength of CDD varies systematically with mycorrhizal …

Strong Dispersal Limitation Of Microbial Communities At Shackleton Glacier, Antarctica, Nathan P. Lemoine, Byron J. Adams, Melisa A. Diaz, Nicholas B. Dragone, Andre L.C. Franco, Noah Fierer, W. Berry Lyons, Ian Hogg, Diana H. Wall

Biological Sciences Faculty Research and Publications

Microbial communities can be structured by both deterministic and stochastic processes, but the relative importance of these processes remains unknown. The ambiguity partly arises from an inability to disentangle soil microbial processes from confounding factors, such as aboveground plant communities or anthropogenic disturbance. In this study, we characterized the relative contributions of determinism and stochasticity to assembly processes of soil bacterial communities across a large environmental gradient of undisturbed Antarctic soils. We hypothesized that harsh soils would impose a strong environmental selection on microbial communities, whereas communities in benign soils would be structured largely by dispersal. Contrary to our expectations, …

Allosteric Site At The Biotin Carboxylase Dimer Interface Mediates Activation And Inhibition In Staphylococcus Aureus Pyruvate Carboxylase, Amanda J. Laseke, Trevor J. Boram, Nicholas O. Schneider, Jeremy R. Lohman, Martin St. Maurice

Biological Sciences Faculty Research and Publications

Allosteric regulation of the essential anaplerotic enzyme, pyruvate carboxylase (PC), is vital for metabolic homeostasis. PC catalyzes the bicarbonate- and ATP-dependent carboxylation of pyruvate to form oxaloacetate. Dysregulation of PC activity can impact glucose and redox metabolism, which contributes to the pathogenicity of many diseases. To maintain homeostasis, PC is allosterically activated by acetyl-CoA and allosterically inhibited by l-aspartate. In this study, we further characterize the molecular basis of allosteric regulation in Staphylococcus aureus PC (SaPC) using slowly/nonhydrolyzable dethia analogues of acetyl-CoA and site-directed mutagenesis of residues at the biotin carboxylase homodimer interface. The dethia analogues fully activate …

The Molecular Circadian Clock Of Phox2b-Expressing Cells Drives Daily Variation Of The Hypoxic But Not Hypercapnic Ventilatory Response In Mice, Aaron A. Jones, Gabriella M. Marino, Allison R. Spears, Deanna M. Arble

Biological Sciences Faculty Research and Publications

While the suprachiasmatic nucleus (SCN) controls 24-h rhythms in breathing, including minute ventilation (V_E), the mechanisms by which the SCN drives these daily changes are not well understood. Moreover, the extent to which the circadian clock regulates hypercapnic and hypoxic ventilatory chemoreflexes is unknown. We hypothesized that the SCN regulates daily breathing and chemoreflex rhythms by synchronizing the molecular circadian clock of cells. We used whole-body plethysmography to assess ventilatory function in transgenic BMAL1 knockout (KO) mice to determine the role of the molecular clock in regulating daily rhythms in ventilation and chemoreflex. Unlike their wild-type littermates, BMAL1 …

Peripheral Clock Disruption And Metabolic Disease: Moving Beyond The Anatomy To A Functional Approach, Gabriella M. Marino, Deanna M. Arble

Biological Sciences Faculty Research and Publications

Sleep and circadian disruption are associated with an increased risk of metabolic disease, including obesity and diabetes. Mounting evidence indicates that misaligned and/or non-functional clock proteins in peripheral tissues critically contribute to the presentation of metabolic disease. Many of the foundational studies which led to this conclusion have focused on specific tissues such as the adipose, pancreas, muscle, and liver. While these studies have greatly advanced the field, the use of anatomical markers to manipulate tissue-specific molecular clocks may not be representative of the circadian disruption that occurs within the clinical population. In this manuscript, we argue that investigators can …

In Light Of Breathing: Environmental Light Is An Important Modulator Of Breathing With Clinical Implications, Aaron A. Jones, Deanna M. Arble

Biological Sciences Faculty Research and Publications

In vertebrate animals, the automatic, rhythmic pattern of breathing is a highly regulated process that can be modulated by various behavioral and physiological factors such as metabolism, sleep–wake state, activity level, and endocrine signaling. Environmental light influences many of these modulating factors both indirectly by organizing daily and seasonal rhythms of behavior and directly through acute changes in neural signaling. While several observations from rodent and human studies suggest that environmental light affects breathing, few have systematically evaluated the underlying mechanisms and clinical relevance of environmental light on the regulation of respiratory behavior. Here, we provide new evidence and discuss …

Tyramine And Its Amtyr1 Receptor Modulate Attention In Honey Bees (Apis Mellifera), Joseph S. Latshaw, Reece E. Mazade, Mary Peterson, Julie A. Mustard, Irina Sinakevitch, Lothar Wissler, Xiaojiao Guo, Chelsea N. Cook, Hong Lei, Jürgen Gadau, Brian Smith

Biological Sciences Faculty Research and Publications

Animals must learn to ignore stimuli that are irrelevant to survival and attend to ones that enhance survival. When a stimulus regularly fails to be associated with an important consequence, subsequent excitatory learning about that stimulus can be delayed, which is a form of nonassociative conditioning called ‘latent inhibition’. Honey bees show latent inhibition toward an odor they have experienced without association with food reinforcement. Moreover, individual honey bees from the same colony differ in the degree to which they show latent inhibition, and these individual differences have a genetic basis. To investigate the mechanisms that underly individual differences in …