Kansas State University

NIH Research Projects · FY 2026 · 2024-07

PROJECT SUMMARY Middle East respiratory syndrome coronavirus (MERS-CoV) emerged suddenly in 2012 as the cause of severe respiratory illness in humans. Despite the high mortality rate (~ 40%) and the significant potential for a public health emergency, there are no FDA-approved vaccines or antiviral drugs for MERS. Consequently, there is an urgent and unmet need for the development of small-molecule drugs to control MERS-CoV infection. Furthermore, members of the Merbecovirus and Sarbecovirus subgenera within the Betacoronavirus genus pose a high risk of future spillover into humans. However, efforts to develop general strategies to mitigate the impact of future pandemics have been limited. Coronavirus 3C-like protease (3CLpro) is a well-characterized therapeutic target as it processes most cleavage sites on virus polyproteins and is essential for virus replication. Multiple series of 3CLpro inhibitors with potent activity against MERS-CoV and in vivo efficacy in mouse models were reported by our group. However, these compound series are parenterally administrable with limited oral bioavailability. Hypothesize of this project is that inhibitors exploiting the exquisite stereochemical control and multiple diversity sites afforded by the 1,3,2-oxazaphospholidin-3-one scaffold (series I and II) and decorated with a novel transition state analog endowed with favorable oral bioavailability can serve as a launching pad for the development of orally bioavailable MERS-CoV-specific antivirals. As these inhibitors can engage in binding interactions with the Sn and Sn' pockets of various coronavirus 3CLpros, the scaffold provides a versatile platform for merbecoviruses and sarbecoviruses. Aims of this project are 1) Conduct iterative structure-guided design, synthesis, and multiparameter optimization of inhibitors for MERS-CoV; 2) Conduct biochemical, structural, and virological studies to characterize and prioritize analogs for MERS-CoV 3CLpro and conduct structure-activity relationship studies with the generated series for merbecovirus/sarbecovirus 3CLpros; and 3) Demonstrate in vivo efficacy of optimized leads in a mouse model of MERS-CoV infection. The overarching goal of this project is the identification of an orally bioavailable preclinical candidate and 1-2 backup compounds based on inhibitor series (I and II) for MERS-CoV infection, and the exploration and utilization of the generated inhibitors against the 3CLpros of merbecoviruses and sarbecoviruses.

NSF Awards · FY 2024 · 2024-07

How we hear the world changes with experience. This auditory perceptual learning can have a heavy psychological influence by modifying the nature of sound's contribution to many subsequent cognitive skills (e.g., multitasking ability, musical aptitude, listening in classrooms, etc.). The impacts of auditory perceptual learning on these skills and on brain activity in regions outside of auditory cortex are under investigated. This project aims to resolve this by training listeners to hear acute differences in sounds and then testing them on their ability to control memory of those sounds under varying circumstances of distraction and multitasking. By measuring brain waves during testing, the project aims to examine how changes in the brain from auditory training relate to the impact of auditory perceptual learning on memory performance. The broader impacts include plans for hackathon events tailored to promote methodological skill development among an interdisciplinary group of undergraduate, graduate, postdoctoral, and faculty scholars. Plans also include a STEM education workshop for middle-school aged girls in Kansas. In the planned studies, human listeners are trained to distinguish a "Target" frequency modulated sound from morphed versions of that target. An untrained target sound is used for later testing comparison. Study 1 plans to measure auditory perceptual learning's impact on the decay of working memory representations by comparing listeners' ability to reproduce trained and untrained sounds from memory using a digital musical instrument. Study 2 plans to measure the susceptibility of trained and untrained sounds to interference during retention. Study 3 plans to use trained and untrained sounds as interference stimuli to determine how auditory perceptual learning affects the ability to inhibit their processing. Study 4 plans to address differences in mental effort needed to retain trained and untrained sounds in working memory through analyses of oscillatory electroencephalography (EEG) activity. Classic representational reweighting perceptual learning theories predict worse working memory fidelity, stronger inhibition, and more listening effort for trained compared to untrained sounds because of the need of attention and/or associative resources for learned increases in perceptual acuity. In contrast, representational plasticity theories predict that increases in the fidelity of sound representations will facilitate working memory processing of trained sounds. Study 5 plans to analyze high-density EEG data to reveal plasticity in the dynamics of distinct auditory and non-auditory brain sources. Study 6 plans to follow this exploratory step with a pre-registered replication that includes additional MRI informed head modeling to increase EEG source localization accuracy. The overall goal is to provide an extensive examination of how auditory perceptual learning impacts working memory and distributed cortical dynamics. This project is jointly funded by the Science of Learning and Augmented Intelligence Program, the Established Program to Stimulate Competitive Research (EPSCoR), and the Perception, Action, and Cognition Program. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NSF Awards · FY 2024 · 2024-07

The study of higher-dimenional spaces has had applications to many different areas, ranging from computer vision to data science. These spaces have many unique and beautiful patterns. Studying these patterns is worthwhile in its own right and may lead to unexpected important applications in the future. Four dimensions is the setting for Einstein’s theory of General Relativity where it is referred to as space-time. Four dimensional spaces have many interesting and unexpected properties. For example, one may find pairs of surfaces so that one surface may be deformed into another, but any such deformation will fail to be smooth in an essential way. Many of the differences between smooth and continuous objects related to four-dimensional spaces disappear after one of several possible stabilization operations is performed enough times. Detecting the required number of stabilizations is a difficult problem because many of the tools that may be used to detect differences between smooth objects fail to work after one stabilization. Using invariants for families of objects is one approach, but many of the key problems are still difficult. The approach this project takes is to consider several related questions where more structure is present. Sometimes the extra structure will make the problem more difficult, but sometimes the extra structure will make the problem easier. The hope is that resolving some of these related questions will provide insight into the more difficult, and more fundamental questions. This is where this project derives its intellectual merit. In addition to the pure research, the PI shares mathematics with many different communities. Notably, the PI is the director of the Navajo Nation Math Circles. Several mathematical activities presented in this community were inspired by more technical problems from the PIs research. This outreach program is the most notable broader impact of the project. In more technical terms, the difficult problem is to find a pair of closed, simply connected, smooth 4 manifolds separated by more than one stabilization. The related approachable questions are analogues for embedded surfaces, diffeomorphisms, and families of such objects. The project will investigate a possible Arf-type invariant for pairs of surfaces, stabilization questions in the symplectic category as well as in families. It will also consider algebraic structures arising from these spaces. Some impacts arise because ideas developed and shared in this proposal may inspire work in adjacent fields. Other impacts arise due to the training and mentoring of future researchers and the mentoring of junior researchers that will take place in this research. The PI is an organizer for Gauge Theory Virtual and runs the MathCircles YouTube channel. The PI has close ties to the Navajo Nation and shares mathematics inspired by his research with this community. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NIH Research Projects · FY 2026 · 2024-07

PROJECT SUMMARY The barrier tissues and body cavities are densely innervated by nociceptor sensory neurons (or nociceptors) that respond to noxious stimuli and mediate pain. Nociceptive innervation in the lung and peritoneal cavity begins as early as the embryonic development stage. Similarly, long-lived tissue-resident macrophages (TRMs), such as alveolar macrophages (AMs) in the lung and peritoneal macrophages (PMs) in the peritoneal cavity, start to populate at the very early stage of life and co-localize close to nerve fibers. However, it is unknown whether neurons can regulate TRM development and impact TRM abilities to respond to injury and inflammation. Upon activation, nociceptor nerve terminals secrete neuropeptides that act on their cognate receptors in macrophages for immunomodulation. The neuropeptide calcitonin gene-related peptide is dominantly secreted in our body by nociceptor sensory neurons. TRMs are well known to exhibit polarization (M1 or M2) depending upon the specific signals they encountered during their development or inflammatory conditions. While M1 macrophages are pro- inflammatory and damage the tissue during infection/injury, M2 macrophages exhibit tissue-protective type 2 inflammation and are crucial for resolving tissue damage and barrier dysfunction. Our preliminary data demonstrated that the nociceptors suppress the abundance of AMs and PMs at steady state, and lack of nociceptor signals polarize AMs and PMs to M1 type during activation with TLR ligands. By investigating AMs and PMs in ex vivo system and in vivo injury model, this R35 MIRA research program will determine the role of nociceptors and their subsets in the development and function of TRMs during steady-state and inflammation. Understanding neuron-TRM crosstalk is critical for determining the mechanism underlying loss of homeostasis, tissue damage, and pathogenesis of complex inflammatory diseases, such as sepsis. Specifically, this research program will address the following three key questions: 1) Do nociceptor neurons play a role in maintenance of TRMs at steady-state? 2) Do nociceptor signals involve in regulating the TRM polarization? 3) What is the role of neuropeptide receptor in TRM maintenance and M1/M2 polarization? Using both ‘loss and gain of function’ neuronal manipulating strategies in mice and using the neuropeptide deficient and neuropeptide receptor deficient mice, we will study the AMs and PMs to address these questions. Targeting the nervous system directly, or through downstream receptor signaling pathways in TRMs, will inform about the host-based strategy as a treatment modality for tissue damage and inflammatory diseases.

NSF Awards · FY 2024 · 2024-07

Many fire-dependent ecosystems have suffered from historical fire suppression, resulting in substantial consequences for the species living in these systems. For example, historical fire suppression tends to result in substantial fuel buildup between fires, so that when fires do occur, they can be intense, likely resulting in large impacts on species in these communities. At the same time, the environment in many ecosystems is predicted to change dramatically, which also affects species in these ecosystems (as well as the rate of fuel buildup, which will modify fire intensity). Predictions of species’ abundances, a commonly used way of assessing potential impacts of threats on a species, often include predictions of current fire effects and climate effects alone, but such predictions rarely incorporate joint effects of current fires, fire suppression, and climate. This research will test how historical and current fire frequencies might alter abundances of a charismatic species, the Venus flytrap, in a future climate and how these environmental drivers might interact with one another to produce unexpected effects. Such efforts are critical to predicting species’ abundances in fire-dependent ecosystems, particularly in areas that have suffered from historical fire suppression. This research aims to build on an ongoing long-term, multi-site demographic study conducted across the range of the Venus flytrap (Dionaea muscipula), which depends on fire to maintain its longleaf pine savanna habitat. The research will estimate the demographic effects of current fires and explore how legacies of historical fire frequency modulate these effects, all while considering additional simultaneous effects of local environmental conditions. The work strives to identify mechanisms of legacy effects by estimating fire intensity and climate-dependent rates of fuel buildup before and after fires, and quantifying the resultant effects on stochastic population dynamics of Venus flytrap. In addition to providing insights into the mechanisms driving legacy effects, this work will also allow us to predict disturbance effects under future environmental conditions for a charismatic species. This project is jointly funded by Population and Community Ecology, and the Established Program to Stimulate Competitive Research (EPSCoR). This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NSF Awards · FY 2024 · 2024-06

Sensors that use quantum effects can be more sensitive to motion and light, have higher spatial resolution, and be more accurate than other types of sensors. This project will focus on hexagonal boron nitride crystals (hBN), which are thin, chemically stable materials, that show great promise for improving the performance of quantum sensors. These sensors work by behaving like tiny magnets whose pole directions can be measured. While powders from hBN have a wide range of applications, including as a whitener in cosmetics, hBN crystals will be particularly useful for sensors because of their high purity and highly ordered arrangement of their atoms relative to other materials. This international collaborative project will grow hBN crystals, measure their optical properties, test their magnetic field sensing capabilities, and determine how the devices can be optimally structured. Ultimately, hBN quantum devices will find new medical applications, including the study of biological processes, virus identification and diagnostics, and discovering new drugs. This project will provide students the opportunity to engage with science and technologies that can benefit society including crystal growth, material characterization, and quantum devices. Both the Kansas State University and Centre National de la Recherche Scientifique groups will undertake outreach activities to intrigue and excite the public and students in the fields of quantum science and technology. Technical Abstract This project will experimentally investigate the methods for creating, and the properties of, optically detectable spin defects in hBN for quantum sensing of magnetic and electric fields. Freestanding, high quality (low intrinsic defect density) hBN crystals will be grown by precipitation from molten metal solutions. Boron vacancies will be created by nuclear transmutation. Carbon doping will be achieved during crystal growth by ion implantation. To gain a deep understanding of the fundamental properties of the defects and to optimize the quantum sensor sensitivities, hBN crystals with specific isotopes of boron, nitrogen, and carbon dopants will be studied. Defect energy states in the crystals will be established by deep ultraviolet photoluminescence (3 eV to 6.5 eV) and optically detected magnetic resonance (ODMR). Quantum devices will be fabricated, and their performance in detecting magnetic and electric fields tested and optimized. This project will address key questions for optimizing hBN quantum sensing including: (1) Which point defects, are most effective in quantum sensors? (2) What defect densities and defect configurations are needed to optimize device performance? (3) To what extent can quantum sensing be improved by employing hBN with specific boron and nitrogen isotopes? (4) Can the ultimate quantum sensing of magnetic and electrical fields be produced from hBN monolayers? A priority of this project is to train the next generation workforce in quantum information science and engineering. Students will learn about crystal growth, the optical characterization of materials, and quantum properties and applications. This project will strengthen the established international collaboration between KSU and CNRS. Both the KSU and CNRS groups will be involved in the outreach activities that are designed for the public and students from a wide range of groups. These activities will demonstrate the creative aspects and the collaborative nature of science, and the benefits of quantum science and technology to society. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NIH Research Projects · FY 2024 · 2023-09

PROJECT SUMMARY Goals can change over time, and it is important to adapt our actions according to our current goals. There is extensive evidence that long-term drug use can lead to dysfunction of neural circuits involved in goal-directed decision-making. However, decision-making impairments are not always apparent in drug users, possibly because drug-induced malfunction in certain brain areas involved in decision-making causes compensation in which the brain reorganizes and/or different strategies are used to maintain adequate decision-making. This proposal will examine changes in behavioral strategy and alterations in neuronal processing that maintain adequate decision-making when the brain areas that normally support decision-making malfunction due to prior voluntary methamphetamine intake or targeted disruption. The proposed studies will assess rats in a devaluation task in which specific responses and cues predict rewards, and then the value of one of the rewards is decreased. Flexible decision-making that is goal-directed would lead to a decrease in responses for the reward with decreased value. Importantly, in our task, the action that leads to the devalued reward is signaled by a response on a lever in a particular spatial location and with a particular light cue above the lever, although normal rats guide their behavior based on the lever-location. However, decreasing the function of prelimbic cortex (usually required to associate a response in a particular location with a specific reward) does not impair the ability to decrease responses on the lever-light compound associated with that reward. Prior research from our lab suggests that animals compensate for the loss of ability to associate the lever-location with the reward (due to prelimbic cortex lesions) by instead associating the cuelight above the lever with the reward, a type of learning that is supported by orbitofrontal cortex. These prelimbic cortex lesions are associated with an increase in neuronal activity in orbitofrontal cortex and in neuronal activity in mediodorsal thalamus neurons projecting to orbitofrontal cortex during learning. As prior research suggests that psychostimulant exposure can lead to alterations in the function of prelimbic cortex and/or lateral orbitofrontal cortex, I will determine long-term effects of prior methamphetamine self-administration on the neural circuits underlying devaluation and whether compensation between brain areas can preserve intact devaluation behavior. In addition, as prior research suggests that voluntary drug-taking causes different neurobiological and behavioral changes than being passively exposed to drugs, I will compare effects of passive methamphetamine exposure to those of voluntary drug-taking. The proposed research is relevant to one component of NIDA’s mission, to “develop new and improved treatments to help people with substance use disorders achieve and maintain a meaningful and sustained recovery”. Our findings may help to understand how drug users may maintain adequate decision-making after drug-induced brain dysfunction, and may identify alternative behavioral strategies that could improve this decision-making after past drug use.

NIH Research Projects · FY 2025 · 2023-09

Project Summary Ions are ubiquitous in nature and all charged biomolecules subsequently develop an ion atmosphere. Unfortunately, our understanding of ion atmospheres at the atomic level is rather limited, and this severely impacts our ability to determine and rationalize protein-protein and protein-DNA interactions, for example. Here, we propose to use the Kirkwood-Buff theory of solutions, coupled with local electroneutrality constraints, to generate an improved view of the ion atmosphere around a variety of biomolecules. The results generate exact relationships between the distribution of anions and cations around charged biomolecules and provide a way to separate the ion contributions to electroneutrality from those related to the preferential interaction of a salt for a biomolecule. A series of theoretical and computer simulation studies are proposed to achieve the two major aims of the project. Aim 1: To Develop an Improved Description of Ion Atmospheres in Biological Systems. Aim 2: To Determine the Consequences of Local Electroneutrality Requirements. The results from these studies will provide a new view of the structure and extent of ion atmospheres around any biomolecular ion and will improve our interpretation of the results from several biophysical techniques, such as osmotic pressure and ion counting studies. Subsequently, this will impact our understanding of a wide range of systems of importance for the study of many health-related diseases.

NIH Research Projects · FY 2024 · 2023-09

PROJECT SUMMARY/ABSTRACT Pulmonary hypertension (PH) is a disease characterized by pulmonary vascular remodeling and poor gas exchange, and eventually leads to right ventricular failure and death. Elevated heart and respiratory muscle workloads contribute to diaphragm and cardiac impairments in PH; however, the physiological and molecular bases are not fully understood. Vascular function is compromised in PH, resulting in an inability to match oxygen delivery to demand, which is of increasing importance in the overworked diaphragm and heart. However, the mechanisms underlying PH-induced vascular dysfunction and, arguably more important, targets for mitigating such dysfunction remain unknown. Upregulation of reactive oxygen species and inflammatory cytokines are thought to promote PH pathogenesis, which suggests that modulation of intracellular redox pathways may serve as one potential mechanism responsible for the impaired vasomotor control with PH and provides a potential therapeutic target to improve the compromised vascular function in PH. Preliminary data supports that PH impairs endothelial-dependent and -independent vasorelaxation in diaphragm arterioles, and therefore diaphragmatic blood flow. Importantly, endothelial-dependent and - independent vasoreactivity may be improved by activation of the transcription factor, nuclear factor erythroid- 2–related factor 2 (Nrf2). However, the role of Nrf2 in improving coronary and diaphragm vascular function in PH has never been determined. Therefore, our global hypothesis is that exercise training and pharmacological Nrf2 activation will improve or restore coronary and diaphragm vascular function in PH. Furthermore, we will assess the reliance upon Nrf2 for these adaptations in order to determine the potential molecular basis for our findings. This project will be completed at Kansas State University (KSU) under the guidance of Drs. David C. Poole and Bradley J. Behnke. The training plan has been formulated to facilitate the development of technical proficiencies and critical thinking skills needed to execute the proposed experiments and incorporates the elements essential for the applicant to transition into an independent scientific career. The Poole and Behnke Laboratories, and the Departments of Kinesiology and Anatomy and Physiology at KSU represent a rich scientific environment that will provide outstanding graduate training and research opportunities to gain new insights into mechanisms of diaphragm blood flow regulation and vasomotor control in healthy and diseased animal models.

NIH Research Projects · FY 2024 · 2023-09

The Burden of occupational hearing loss (HL) is severe, having negative impacts on health care costs and quality of life. There is a strong Need to address barriers to wearing hearing protection devices (HPDs) that can prevent HL. This is especially true in regard to: (1) listening performance decrements that occur while wearing, and (2) the operational environments of first responders whose workplace conditions allow relatively little control over noise. This project will characterize HPD-related performance decrements, their impact on choice to wear HPDs, and how auditory training can be used as a means to alleviate decrements. Our innovative approach will use a paradigm where speech informs subjects to perform specific aspects of a sensorimotor task. This mimics critical communication scenarios in first responders (e.g., a firefighter given speech commands that inform her/his performance on another task). HPD listening will be simulated with a digital filter designed to mimic the attenuation profile of an actual HPD. Electroencephalographic (EEG) data will allow covert examination of neural signatures of ongoing cognitive processes. The approach will allow the characterization of HPD-related performance effects to a level of detail not achieved before, while at the same time maintaining research-to-practice relevance in the mapping of our experimental task to first responder operational situations. AIM 1 will characterize HPD-related decrements in performance. We expect that comparison of HPD and no HPD conditions will reveal the extent to which HPD use impacts multiple dimensions of performance (e.g., speech comprehension, sensorimotor task accuracy, and mental effort). AIM 2 will determine whether or not performance decrements impact choice to wear HPDs. Here, we will allow subjects to voluntarily toggle their simulated HPD on and off, while at the same time manipulating performance incentives to examine how listening difficulty impacts time spent "wearing" hearing protection. AIM 3 will test an auditory training approach to alleviating performance decrements. Here, we will compare effects of auditory training in HPD and no HPD conditions on multiple dimensions of performance. Aim 1 Impact will be in knowledge gains that cannot come from standard survey and focus group methods. The Impact of Aim 2 will be to provide an assessment of how performance decrements impact actual choice to wear. The Impact of Aim 3 will be to provide a means to address performance decrements in HL prevention programs (HLPPs). Relevant NIOSH strategic goals include goals to: "reduce occupational hearing loss", and inform "hearing loss prevention education for employers and workers". NORA sector groups of public safety, construction, and manufacturing have clear relevance. Outputs include publications and conference presentations at interdisciplinary venues that will accelerate research-to-practice directions. Outcomes entail new approaches to addressing HPD use rates, and eventually, reduced occupational HL.

NIH Research Projects · FY 2025 · 2023-08

Eukaryotic translation initiation is a complex process involving the ribosome, mRNA, Met-tRNAiMet and numerous eukaryotic initiation factors (eIFs). Decades of studies driven by those using the model eukaryote yeast Saccharomyces cerevisiae revealed that the key process is the formation of codon-anticodon base pairing in the small ribosome P-site. Stringent initiation is enabled by formation of the 48S ribosomal pre-initiation complex (PIC) strictly at the AUG start codon while excluding initiation at other sites. Intriguingly, however, many non-canonical start sites are utilized in some biological contexts and diseases such as cancer and neurodegenerative disorders. The list of non-AUG start sites within the human genome is far from being complete and how the use of these sites and hence protein production from these sites are regulated remains an open question. Thus, Aim 1 of this grant is to make such a list of non-AUG start sites through genome-wide translation profiling of well characterized cancer model systems, verify some of these sites and determine the mechanism driving the observed non-AUG translational regulation in cancer. The Aim 2 is to study the mechanistic role of 5MP and Met-tRNAiMet adenosine N6- threonylcarbamoylation (t6A) in controlling non-AUG translation. It will be tested if 5MP mutations found in many types of cancer can alter initiation accuracy, thereby affecting patients' prognosis. Our preliminary studies suggested that t6A located 3' of Met-tRNAiMet anticodon can discriminate specifically against GUG and UUG start codons, in contrast to eIF1 being more universal non-AUG discriminator. Combining molecular dynamics simulation methods, we will test if the recently discovered cyclic t6A serves the discriminating role and determine how the cooperation or competition between t6A and eIF1 promotes stringent initiation and leaky scanning crucial for translational regulation. The Aim 3 is to study yet a distinct mechanism of start codon selection that is exploited during the heat shock response at the translational level. This mechanism was discovered through translational profiling of yeast eIF3i mutant defective in its interaction with RNA-binding eIF3g subunit at a high temperature. The working hypothesis assumes that, at a high temperature, stable PIC formation at the AUG codon requires additional mRNA elements anchoring the initiating ribosome at its entry site. These hypothetical mRNA elements are located downstream of the start codon and include a novel eIF3g-binding motif 5'-GUCG-3' and a downstream stem- loop that potentially binds the entry site-side of the 40S, thereby stabilizing the PIC formation. This model will tested using yeast as a model system.

NIH Research Projects · FY 2024 · 2023-07

HPV infections must persist for years to decades to cause cervical cancer. During this time, the host genome acquires mutations that promote tumorigenesis. Do HPV oncogenes (HPV E6 and E7) play an active (causing mutations by disrupting DNA repair) and/or a passive (via degradation of tumor suppressors like p53 and RB) role in the acquisition of these mutations? While it is established that HPV oncogenes degrade tumor suppressors, there is evidence that they may also actively promote genome destabilization. During the viral life cycle, HPV E6 and E7 induce a hyperactivation of DNA damage signaling and recruit repair factors to sites of viral replication. Our group and others have shown that HPV oncogenes also change how cells repair double stranded breaks in DNA (DSBs). Our published data and data presented in this proposal provide further details that show that HPV oncogenes shift DSB repair from error free mechanisms (homologous recombination or HR) to error prone (microhomology-mediated end joining or MMEJ) mechanisms. These data suggest that HPV E6 and E7 makes DSB repair more mutagenic, but this has yet to be demonstrated. Other substantial questions also remain. How do HPV oncogenes promote the shift towards repair by MMEJ? Do HPV oncogenes promote canonical MMEJ or does the switch to MMEJ result after HPV oncogenes block completion of HR? If HPV makes DSB repair more mutagenic, is the increase universal or does the presence of non-allelic homology (via repetitive Alu elements) augment HPV-mediated mutagenesis? Similarly, if HPV oncogenes make DSB repair mutagenic do they contribute equally to the process? Aim 1 will address mechanistic question regarding how HPV oncogenes promote the use of MMEJ and how the pathway is initiated, using a combination of live and fixed cell microscopy. Aim 2 will define the extent that HPV oncogenes make DSB more mutagenic and the extent that their mutagenic properties are further enhanced by the presence of Alu elements. Aim 2 will use a novel reporter construct and droplet digital PCR, along with deep sequencing approaches and novel bioinformatic pipelines to accomplish these goals. These approaches have been pioneered by our research team. These innovative approaches will facilitate an improved understanding of the fundamental processes that drive cervical cancer development. Given that cervical cancers are the 4th most common cancer in women and kill someone every 90 seconds, this information is important. The knowledge gaps addressed in this proposal are also relevant to understanding why most HPV infections do not result in cervical cancer and for developing methods to prevent those that do. Finally, given that cervical cancers are often treated with genotoxic agents (e.g., cisplatin or radiotherapy), understanding how HPV changes DNA repair could lead to the identification of ways to augment these interventions. For example, if HPV oncogenes promote MMEJ via a delayed entry into the pathway, small molecule inhibitors of proteins involved in terminal MMEJ steps would likely result in a tumor-specific enhancement of radiotoxicity.

NIH Research Projects · FY 2026 · 2023-02

Aging is a primary risk factor for development of cardiovascular dysfunction and disease. The hallmarks of vascular aging are endothelial dysfunction, development of a synthetic, atherosclerotic phenotype in smooth muscle, and arterial inflammation and stiffening. We have shown that aerobic exercise training can mitigate or reverse age-related vascular dysfunction and adverse arterial remodeling; however, the cellular signals that contribute to the ability of exercise training to promote macro- and microvascular resiliency remain unidentified. Similarly, the mechanisms whereby exercise training reverses age- related vascular dysfunction remain unknown. Reduced circulating adiponectin has been associated with the adverse vascular changes that occur with advancing age; however, a role for adiponectin in age- related vascular dysfunction has not been demonstrated. We have reported that circulating adiponectin levels increase in response to late-life exercise training; however, a direct role for adiponectin signaling in reversal of age-related vascular dysfunction by exercise training has not been demonstrated. We propose to test a central hypothesis that 1) loss of adiponectin is a critical contributor to age- related vascular dysfunction and adverse arterial remodeling, and 2) adiponectin contributes to the ability of exercise training to promote vascular resiliency and reverse age-related vascular dysfunction and age-related adverse vascular remodeling. We propose to study sedentary and exercise trained mice, across the murine lifespan, to determine 1) the impact of loss- and gain-of-function of adiponectin on ceramide/sphingosine signaling in the endothelium of the microvasculature of the heart and skeletal muscle, 2) the impact of loss- and gain-of-function of adiponectin on development of a senescence-associated synthetic phenotype in vascular smooth muscle and contractile dysfunction the microvasculature of the heart and skeletal muscle, and 3) the impact of loss- and gain-of-function of adiponectin on remodeling of large arteries. Results from the proposed work will increase our understanding of the role of adiponectin in age-related vascular dysfunction and exercise training-induced reversal of age-related vascular dysfunction. A top biomedical research priority is to identify strategies which promote vascular resiliency with advancing age or which reverse age-related vascular dysfunction. The proposed work could identify 1) components of the adiponectin signaling pathway that could be targeted for prevention of age-related vascular dysfunction, and 2) novel exercise mimetics that could be employed for 1) promotion of vascular resiliency across the lifespan, and/or 2) reversal of age-related vascular dysfunction.

NIH Research Projects · FY 2026 · 2022-09

PROJECT SUMMARY The hallmark symptom of Alzheimer's disease (AD) and most common complaint among cognitively healthy older adults is memory loss, especially for everyday events such as conversations with a loved one, a meal with friends, a trip to the grocery store. However, there is a critical difference between remembering these types of events and those that are often measured in the laboratory or in neuropsychological batteries, which often lack real-world contextual meaning. This project will investigate failures in memory for everyday activities by using dynamic real-world stimuli in which episodic memory is formed during a continuous stream of experience. We will test the extent to which older adults use semantic knowledge to create stable mental representations during the continuous stream of everyday experiences, and whether this ability changes in the early stages of AD. Such knowledge-related improvements could benefit older adults' ability to remember day-to-day information, make effective decisions in everyday life (e.g., decisions about healthcare and estate planning), and interact with new technology––all of which will improve their quality of life. This goal is highly relevant to the NIH core mission “to seek fundamental knowledge about the nature and behavior of living systems and the application of that knowledge to enhance health, lengthen life, and reduce illness and disability.” Aim 1 of this project will determine whether deficits in event memory are explained by age-related differences in maintaining stable mental representations during an experience. Aim 2 will determine whether older adults can effectively integrate new event information into existing knowledge structures. Aim 3 will determine whether cueing prior knowledge improves event memory in early-stage AD. The project will use an innovative combination of behavioral and neurophysiological measures of event encoding to address these aims. It will also use dynamic activities that are often encountered in daily life—the kind that older adults report having difficulties remembering. We predict that mPFC-mediated prior knowledge will facilitate the integration of new event information with prior knowledge resulting in better segmentation and event memory for older adults. However, when no prior knowledge is available, the extent to which people can effectively segment an activity (supported by mPFC-hippocampal coupling) will predict memory performance. Further, we predict that cueing relevant knowledge will scaffold the learning of new schema-consistent event information in cognitively healthy older adults and those with early AD. Our goal of improving older adults' ability to encode and retrieve everyday activities is aligned with the NIA's vision for older adults to “enjoy robust health and independence, remain physically and mentally active, and continue to make positive contributions to their families and communities.”

NIH Research Projects · FY 2025 · 2022-09

PROJECT SUMMARY The goal of the proposed research is to understand how gene regulatory networks (GRNs) are modified to generate structures repeated throughout the body. GRNs organize the activation of hundreds of genes under the control of one or few transcription factors or signaling molecules. The activation of specific GRNs designate cell type. The reuse of a GRN in different tissues of the body is thought to generate repeated body parts such as hair, muscles, or neurons. This is generally hypothesized to proceed by the redeployment of factors situated high within the GRN to a new context. Despite much effort to identify the mutations that lead to GRN redeployment, it has remained elusive. The proposed research will identify the genetic changes that led to the redeployment of a GRN that has been extensively characterized and manipulated in Drosophila. Furthermore, I will investigate how the architecture of a GRN can be modified in a tissue-specific fashion. Most studies have focused only on the upstream factors that control GRNs, but I will use genomic techniques to investigate how downstream genes in the network are activated by and connected to their upstream transcription factors. I will determine if the same regulatory elements and direct binding sites are reused in all tissues or if they vary between tissues. This proposal will use cutting edge transgenic techniques to not only describe associations but test predictions through genetic manipulation. I will determine which genetic changes are necessary and sufficient for the redeployment and modification of a GRN. The ultimate goal will be to edit the genome to redeploy a GRN into a naive background. The proposed work will generate one of the most complete models a GRN’s redeployment across tissues. This model can help us understand what genetic changes may move a GRN into a new tissue and whether the full GRN will be redeployed in the new context. Human health conditions with large phenotypic effects such as birth defects have been traced back to mutations in regulatory elements of upstream factors which lead to ectopic expression and the generation of repeated structures in new locations. The proposed work will establish a general model for causes of ectopic expression, providing general insights into the architecture of GRNs governing repeated structures in a variety of systems.

NIH Research Projects · FY 2025 · 2022-06

PROJECT SUMMARY Hallmark features of many forms of cardiovascular disease include exercise intolerance and a high risk of suffering an adverse ischemic cardiovascular event such as cardiac fibrillation, myocardial infarction, or stroke during physical exertion. An exaggerated increase in sympathetic nervous system activity during exercise (i.e., sympathoexcitation) is a direct contributor to exercise intolerance and the risk of such adverse events. During exercise, mechanical forces associated with contracting skeletal muscles stimulate small diameter muscle sensory neurons (group III/IV muscle afferents) which plays an integral role in the activation of a reflex, the exercise pressor reflex, that contributes to increased sympathetic nervous system activity during exercise. The goal of this project is to investigate the cellular signaling mechanisms that result in exaggerated mechanically- activated exercise pressor reflex sympathetic control signals in cardiovascular disease. Specifically, we will use a rat model of limb ischemia in which a femoral artery is chronically ligated (a model of simulated peripheral artery disease) and a complementary blend of molecular and whole-animal approaches to investigate the signaling pathways within muscle sensory neurons that result in a pathophysiological enhancement of mechanically-activated channel function. The incorporation of multiple experimental techniques including molecular, electrophysiology, reflex, and conscious exercise experiments will ensure that our findings are robust, integrative, and translational in nature. In Aim 1, we will investigate the role played by inositol 1,4,5-trisphosphate (IP3) receptors and altered calcium signaling in group III/IV muscle afferents in the exaggerated mechanical component of the exercise pressor reflex (i.e., the mechanoreflex) in rats with chronic limb ischemia. In Aim 2, we will investigate the role played by exchange protein activated by cAMP (EPAC), especially EPAC 1, signaling in group III/IV muscle afferents in the exaggerated mechanoreflex in rats with chronic limb ischemia. In Aim 3, we will investigate the role played by protein kinase C (PKC), especially PKCε, signaling in group III/IV muscle afferents in the exaggerated mechanoreflex in rats with chronic limb ischemia. This project is innovative because it is the first to systematically investigate the signaling mechanisms that modulate the function of mechanically activated channels that contribute to sympathoexcitation during exercise in cardiovascular disease. This project is significant because the experiments may identity three novel targets (IP3 receptors, EPAC1, and PKCε) for therapies aimed at mitigating sympathoexcitation, exercise intolerance, and/or elevated risk of ischemic events in cardiovascular disease patients.

NIH Research Projects · FY 2025 · 2021-08

Kansas State University and three community college partners from southwest Kansas; Dodge City Community College, Garden City Community College, and Seward County Community College, have had a thriving Kansas Bridges to the Future partnership during the past sixteen years. With the recent change in the funding mechanism from an R25 to a T34, this new program proposal is seeking NIH support for a new five- year grant cycle in order to recruit talented individuals with unique perspectives and experiences to the biomedical workforce. To date, 143 students from first generation have benefited from the Kansas State University Bridges to the Baccalaureate training program and at least 39 have pursued advanced research degrees or entered professional health programs. This proposal shows solid support from all four colleges to maintain a critical and successful pathway for Bridges students to enter the university: 1) by building relationships with the students and their families while at the community colleges; 2) by bringing students and their families to K-State to help them become familiar with the larger campus, the support staff, and previously matriculated Bridges students; 3) by providing an established, highly successful undergraduate research program, the Developing Scholars Program, to support them academically and personally; and 4) by providing seminars, workshops, lab experiences, and research internships to help students explore their options in STEM disciplines for biomedical careers. Through the Bridges program, students are prepared to succeed in graduate and professional programs, and to establish thriving professional careers. Kansas State University will continue to provide 100% tuition for 2 years of study at the university, thus removing cost-related barriers that are often insurmountable for students. Each of the community colleges will also continue to provide tuition scholarships to Bridges students to complete their associate degrees. The overall goal of this project is to provide biomedical research training and mentoring in order to increase the number of students with baccalaureate degrees in STEM disciplines for future careers in the biomedical, clinical, behavioral and social sciences. Further, this project will support the goals of the National Institutes of Health for enhancing public trust, solving complex problems, addressing challenges in biomedical research, and ensure a pool of highly trained biomedical scientists.

NIH Research Projects · FY 2026 · 2021-08

PROJECT SUMMARY Human coronaviruses generally cause the common cold, a mild upper respiratory illness, however, global outbreaks of new human coronavirus infections with severe respiratory disease have periodically emerged from animals. These include Severe Acute Respiratory coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and, most recently, SARS-CoV-2, the causative agent of coronavirus disease 2019 (COVID-19). Currently, there are no licensed vaccines or antiviral drugs against these viruses, underscoring an urgent need for the development of preventive and therapeutic measures against coronaviruses. Coronavirus genomes encode large polyproteins which are processed by a 3C-like protease (3CLpro) and a papain-like protease. Both proteases are essential for viral replication, making them attractive targets for drug development. Our foray in this area has resulted in the discovery of broad-spectrum inhibitors of multiple viruses, including coronaviruses and noroviruses that encode 3CLpro, as well as the first demonstration of clinical efficacy by a feline coronavirus 3CLpro inhibitor. Recently, we have demonstrated that a dipeptidyl series of compounds potently inhibit human coronaviruses, including MERS-CoV and SARS-CoV-2 in cell culture, and display in vivo efficacy in the DPP4-KI mouse model of MERS-CoV infection. The antiviral target of the compounds was validated by obtaining high resolution crystal structures 3CLpro-inhibitor complexes from SARS-CoV, SARS- CoV-2 and MERS-CoV. We hypothesize herein that the identified series can serve as a launching pad for the development of SARS-CoV-2-specific antivirals. The immediate and overarching goal of the proposed studies is to further optimize the pharmacological activity PK parameters of identified lead inhibitors of SARS-CoV-2 3CLpro and the demonstration of in vivo efficacy against SARS-CoV-2. The expected outcome of our studies is the selection of a preclinical candidate (and 1-2 backup compounds) that is well-suited to conducting further preclinical studies, ultimately leading to the development of a COVID-19-specific antiviral therapeutic.

NIH Research Projects · FY 2026 · 2021-05

PROJECT SUMMARY/ABSTRACT The innate immune system provides an essential defense against both invading microorganisms and parasitic opportunists. In humans, a robust early innate immune response requires immediate and concerted action by humoral and cellular components, which are represented by the complement system and neutrophils, respectively. Efficient defense against microorganisms and parasites by this “complement/neutrophil axis” is predicated upon a network of molecular interactions as well as biochemical reactions catalyzed by proteases, peroxidases, and related enzyme systems that are activated in response to specific biological triggers. Because complement and neutrophils are among the first host defenses encountered by invading microorganisms and parasites, there is strong selective pressure for them to evolve means to evade complement and neutrophil function. Indeed, work from the last two decades has shown that the pathogen Staphylococcus aureus expresses over 30 different proteins as part of its innate immune evasion repertoire. We have extensively studied S. aureus innate immune evasion from a protein structure/function perspective and found that many such evasion proteins are potent enzyme inhibitors that block proper functioning of the host complement/neutrophil axis. Our recent work on salivary proteins from the blood-feeding sandfly, Lutzomyia longipalpis, strongly suggests that enzyme inhibition is a general principle underlying the phenomenon of innate immune evasion. This MIRA outlines our ongoing research into new modes and mechanisms of inhibiting enzymes that function in the early innate immune system. Our major activities will focus on three broadly related, yet independent avenues of investigation. The first project concerns S. aureus EAP domain proteins. In the prior funding period, we made the surprising discovery that members of this inhibitor family can block two different neutrophil serine proteases simultaneously. We will investigate this observation in more detail, and explore how a particular EAP protein alters the formation and function of neutrophil extracellular traps. The second project concerns the SALO family of proteins from L. longipalpis. In the prior funding period, we unexpectedly found that SALO proteins inhibit the proteolytic reactions needed to cleave pro-proteins into their bioactive counterparts. We will continue our studies on SALO proteins as part of a new line of inquiry. The third project concerns the SPIN family of myeloperoxidase inhibitors secreted by various Staphylococcal species. By using our SPIN data gathered in the prior project period, as well as obtaining complementary new insights on SPINs, we will work to develop a model that defines the physical principles underlying the host species specificity of evasion proteins.

NIH Research Projects · FY 2025 · 2021-05

Insects have an innate immune system that protects against infections by pathogens and parasites. The overall goal of this project is to investigate proteins in insect hemolymph plasma that participate in different aspects of insect immunity. Previous work from this laboratory has established the lepidopteran insect, Manduca sexta, as a model system well suited for biochemical characterization of the complex functions of hemolymph proteins. In our work over the next five years, we plan to investigate three aspects of immunity that are mediated by plasma proteins. (1) We will characterize interactions of plasma proteins with peptidoglycan from Gram-negative and Gram-positive bacteria that trigger activation of a serine protease, thereby initiating protease cascades that result in activation of phenoloxidase and the Toll pathway. (2) We will investigate how the redox environment of hemolymph is regulated during an immune response and test a hypothesis that immune proteins may be regulated by thiol modifications. (3) Mammals have well-characterized mechanisms for depriving invading microorganisms of iron; however, immune-related iron-withholding in insects is still poorly understood. We will use M. sexta as a model for discovering conserved iron-withholding mechanisms in insects. The fundamental biochemical knowledge gained as a result of this research is expected to stimulate better understanding of regulation of protease cascade pathways and molecules in insect hemolymph that contribute to oxidative modulation during immunity, and lead to understanding of how iron influences human disease transmission by insect vectors.

NIH Research Projects · FY 2025 · 2020-09

Project Summary Strengthening Antibiotic Resistance Surveillance in Retail Food Specimens in Kansas as a Part of the National Antimicrobial Resistance Monitoring System As a key activity in combating bacterial antimicrobial resistance (AMR), the National Antimicrobial Resistance Monitoring System (NARMS) since 1996 monitors AMR in foodborne pathogens and indicator bacterial species in food-animals at the time of their processing; in red meat, poultry, and since 2020 also in seafood products sold to the public in retail; and in human foodborne infections. The program monitoring AMR in retail food is led and managed by the Food and Drug Administration – Center for Veterinary Medicine (FDA-CVM). The food sample collection and microbiologic analysis are performed by the program sites in individual states. The site in Kansas was established in 2016, and the site-team has performed the NARMS Retail Food Surveillance programmatic activities of collecting and subjecting to microbiologic and whole genome sequencing analysis samples of food retailed in Kansas. The actual PIs have taken the leadership of the project and conducted NARMs in Kansas since October 2023. One of the major innovations in the program in recent years has been addition of whole genome sequencing and annotation of the bacterial isolates obtained from retail food samples. We incorporated bacterial isolate identification by MALDI-TOF in October 2023. This new project will enable the Kansas site-team to continue the prior programmatic activities in Kansas, microbiologic characterization and routine whole genome sequencing and annotation of bacterial isolates obtained from food samples collected in retail stores in Kansas as implemented and optimized over the past 5 years. The isolates, and their epidemiologic and genomic data will be delivered to the NARMS Retail Food Surveillance program on the required schedule. The program team will use these data and materials to enhance AMR surveillance and foodborne outbreak analysis and enable program and policy development at the national level. Epidemiologically relevant AMR information of target bacterial species isolated from food collected in retail stores in Kansas will be provided semiannually to the Kansas Department of Health and Environment (KDHE) to advance public health in the state and inform program and policy development. Additionally, this information will be made available to county and community public health offices upon request. The data will be also used by our team for educational and outreach purposes throughout the state, to raise public awareness of AMR. Therefore, this project will strengthen AMR surveillance and analysis, support foodborne outbreak investigation, inform antimicrobial drug stewardship, and promote public health in Kansas and nation-wide.

NIH Research Projects · FY 2025 · 2020-07

The objective of the short-term research training program, the Veterinary Research Scholars Program (VRSP), is to provide veterinary students having completed their 1st or 2nd year, with an intensive 12-week summer research-oriented experience, a research mentor & advocate, and journal clubs & workshops to teach research study design and skills, research ethics, and writing and presenting research results. This application requests funding for 8 scholars annually for 5 years who will be paired with elite faculty research mentors representing 10 departments at KState. Scholars will benefit from strong K-State research expertise in the areas of 1) infectionimmunity & public health, 2) comparative medicine-model organisms-translational research, 3) cellular function in health and disease, and 4) basic and applied physiology & pharmacology. To ensure that the most highly qualified applicants apply, scholars will be actively recruited from the K-State CVM as well as nationally and internationally. In addition to mentored hypothesis-driven research and weekly activities, scholars will benefit from guest speakers and tours to local research facilities (i.e. corporate, USDA) to meet veterinarian researchers and learn about exciting career options. All scholars will be required to present their research at the K-State Summer Research Day, National Veterinary Scholars Symposium, as well as at the K-State Phi Zeta Research Day and will be encouraged to publish their work in peer-reviewed journals. Through providing this intensive summer experience, the goal of the VRSP is to provide the foundational tools and inspiration for talented veterinary scholars to pursue research degrees and careers as veterinarian researchers. Since K-State VRSP’s inception in 1998, more than 270 scholars have completed research through the K-State VRSP and more than 40% subsequently pursued advanced training, demonstrating the impact of the mentored research program on supplying veterinarian researchers to today’s workforce. Program alumni have become successful veterinarian researchers, advancing science with careers in academic research and teaching, public health (e.g., CDC, USDA), and in public policy development. The VRSP has an experienced leadership team, with both an external and internal advisory committees to ensure this success continues. With strong K-State, CVM, and faculty commitment to programmatic success, cutting edge research with outstanding biomedical scientists and laboratories at K-State, and renewed NIH support from the T35 program, K-State’s VRSP aims to continue leading the way in training the veterinarian researchers of tomorrow.

NIH Research Projects · FY 2024 · 2020-06

PROJECT SUMMARY Spirochetes of the Borrelia genus are the cause of several prevalent vector-borne diseases. The most well-known pathogen from this group is Borrelia burgdorferi sensu stricto, which causes over 300,000 cases of Lyme disease in the United States each year. B. garinii and B. afzelii, which belong to the B. burgdorferi sensu lato complex, are the primary agent of Lyme disease in Europe and Asia. Borrelia spirochetes are also the etiological agent of the ancient human disease relapsing fever, as well as a newly recognized infectious condition called Borrelia miyamotoi disease. Lyme-associated, relapsing fever-associated, and B. miyamotoi spirochetes have differing lifecycles and their infections are accompanied by distinct clinical presentations. However, each of these pathogens are known to encode multifunctional surface-expressed lipoproteins that interact with vertebrate host molecules. Among these proteins are a small arsenal of immunomodulators that specifically target and inactivate a primary arm of innate immunity known as the complement system. We have recently reported two independent lines of evidence that support the hypothesis that one of these pathways, known as the classical pathway, is important in controlling B. burgdorferi infections. First, we have shown that mice deficient in the pattern recognition molecule of the classical pathway, C1q, are significantly more susceptible to B. burgdorferi infection. Secondly, we have shown that the lipoprotein B. burgdorferi BBK32 is a high-affinity inhibitor of the initiating protease of the classical pathway, C1r. In Aim 1 of this project we seek to understand the C1r inhibitory activity of BBK32 sensu lato proteins at the molecular level. In Aim 2 we will determine the immunomodulatory roles and virulence contribution of three BBK32 orthologues known as FbpA, FbpB, and FbpC which are found uniquely in relapsing fever and B. miyamotoi spirochetes. In Aim 3 we will delineate the role of C1r inhibition in borrelial pathogenesis using in vivo models of disease. To achieve this, we propose a multi-disciplinary strategy that employs x-ray crystallography, biophysical approaches, and complement functional assays to pinpoint key ‘hot-spot’ residues on BBK32 that give rise to its potent anti-C1r activity. These data will inform the design of bbk32 mutants which will be used in mouse infectivity studies to connect structural features of BBK32, at the amino-acid level, to an in vivo phenotype. Parallel studies will use genetic deletion mutants of fbp genes from the relapsing fever- associated spirochetes B. turicatae and B. hermsii. These studies will be paired with experimental models of Lyme and relapsing fever borrelioses using C1r-/- mice to better understand the role of the classical pathway initiating protease in the control of borrelial infections. By addressing fundamental questions of how medically important Borrelia spirochetes recognize and evade host immunity, the studies proposed here stand to have a broad and significant impact on the field of bacterial pathogenesis.

NIH Research Projects · FY 2025 · 2018-07

Project Summary: The purpose of this application is to facilitate participation by the Kansas State Veterinary Diagnostic Laboratory in Vet-LRN Program Office (VPO) case investigations. General procedures such as information flow, sample handling procedures, submission of reports and billing for services are discussed. The focus of most Vet-LRN case investigations is on diagnostic samples, although occasionally animal food samples will also be submitted. The VPO will be the client. Tests conducted will depend on the sample type and the complaint, and will be under the discretion of VPO. Test types will fall in the disciplines of pathology, toxicology, and microbiology. Standardized methods will be used when possible, but methods may be adapted to a new matrix if necessary. Methods will be included in reports.

NIH Research Projects · FY 2026 · 2017-10

Project summary Organism development and cellular homeostasis depend on tightly regulated gene expression programs. Disruptions in gene regulation lead to developmental defects and contribute to human diseases including cancer and neurodegenerative disorders. MicroRNAs (miRNAs), small non-coding RNAs, play a critical role in post-transcriptional regulation of gene expression by repressing target genes. Dysregulation of miRNA activity can lead to disproportionate gene silencing or overexpression, with damaging consequences to organism development and health. Despite the significant role of miRNA function in development and disease, our understanding of how miRNA activity is regulated to maintain appropriate levels of gene repression remains incomplete. The overarching goal of this research is to understand how the gene-regulatory activity of miRNAs is controlled within the complex context of a developing organism. More specifically, we will investigate how miRNA target specificity is established through regulated, miRNA strand specific loading of the miRNA induced silencing complex (miRISC) and how key miRISC components and cofactors impact gene-regulatory miRNA activity. We will continue to leverage the power of C. elegans and will, through a range of methodologies, delineate the in vivo genetic and molecular networks regulating miRNA activity at steps of miRNA biogenesis and target repression. This research is expected to lay a foundation for understanding how gene regulatory programs are maintained during organism development through robust regulation of miRNA activity and how dysregulation of miRNA function leads to loss of gene expression control in disease.