Oregon Health & Science University

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY/ABSTRACT Prematurity occurs in 10% of births (∼ 400,000/year) and is the leading cause of impaired lung development and increased respiratory morbidity. Preterm infants often require respiratory support in the neonatal intensive care unit (NICU) and experience respiratory morbidity throughout childhood, including increased wheeze, asthma diagnosis, and respiratory rehospitalizations. Preterm birth contributes to impaired lung function into adulthood, increasing the risk of chronic obstructive pulmonary disease. Nasal continuous positive airway pressure (CPAP) is routinely used in the NICU for respiratory distress in preterm infants. However, once respiratory stability is met, the usual care is to discontinue CPAP. Our recent randomized clinical trial (NCT#04295564) showed that in stable preterm infants in the NICU meeting predefined criteria for discontinuing CPAP (dCPAP; usual care), those randomized to 2 weeks of extended CPAP (eCPAP) not only had larger lung volumes in the NICU, but importantly the eCPAP group also had greater alveolar volume, gas exchange, and higher forced expiratory flows at ∼ 6-months corrected age with reduced wheeze through 12 months. These findings support our hypothesis that eCPAP stimulates lung growth, resulting in better airway and parenchymal function following NICU discharge. Our RCT study is the first intervention to demonstrate lasting improvement in lung growth and function in preterm infants-a key NIH priority. The aims of this proposal are to continue to study the former preterm infants from this unique cohort to determine whether eCPAP in stable preterm infants in the NICU has a persistent long term positive effect on airway and lung growth and function through school age (specific aim 1). In specific aims 2 and 3 we will examine the structural and molecular mechanisms by which eCPAP may be improving lung development. In specific aim 2, we will use an already IRB approved single low dose high-resolution computed tomography (HRCT) scan done at 7 years of age to determine if increased airway size underlies the improved airway function in the eCPAP group. In specific aim 3, detailed biological data including pulmonary DNA methylation and transcriptomics will be used to identify patient clusters or sub-groups that share a common disease mechanism and are most likely to respond to eCPAP. Molecular endotypes will be linked with airway/parenchymal function, structural characteristics, and respiratory outcomes. Yearly lung function tests and quarterly standardized respiratory questionnaires will be performed. Nasal swabs, a blood draw, and a single low dose HRCT scan will be done at 7 years of age. This follow-up will determine if extending CPAP in the NICU persistently improves lung function and respiratory morbidity (including asthma) into school age, determine if the mechanism for the improved airway function is increased airway size, and assess endotype characteristics in school-age children born preterm and randomized to eCPAP vs dCPAP. These data will reinforce the role of eCPAP in transforming NICU treatment for preterm infants to sustainably improve long-term respiratory outcomes.

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY Urinary stone disease (urolithiasis) is a prevalent and global health issue, affecting approximately 9% of the U.S. population and over 10% in many developed countries. Due to lifestyle changes and global warming, the prevalence of urolithiasis has been increasing. Cystinuria, characterized by an abnormal elevation of cystine concentration in the urine, is the most common monogenic cause of urolithiasis and significantly contributes to the disease burden, accounting for approximately 10% of pediatric cases and affecting 1 in 7,000 births worldwide. This condition is caused by biallelic loss-of-function mutations in the SLC3A1 gene (type A) or the SLC7A9 gene (type B), which encode the two components of the b(0,+)-type amino acid transporter, rBAT and b0,+AT, respectively. This transporter is expressed exclusively in proximal tubes of the kidney and responsible for cystine and dibasic amino acid reabsorption from urine. Due to the poor solubility of cystine at high urinary concentrations, patients with cystinuria suffer from recurrent formation of cystine caliculi in the urinary tract starting in childhood or adolescence, which leads to progressive kidney damage and significant reductions in quality of life. Current conversative treatments including hyperhydration, urinary alkalization, dietary restrictions, and pharmacological treatments, have limited efficacy and are often poorly tolerated due to side effects. As a result, patients require repeated surgical interventions for stone removal, which also has the risk of progressive impairment of renal functions . Therefore, there is an urgent and unmet need for innovative therapies that address the root cause of cystinuria and offer a potentially cure. To make breakthroughs in this field, this grant proposal aims to develop clinically applicable novel AAV vector-mediated gene therapy for cystinuria, with a focus on cystinuria type B (CysB) as the prototype for the therapy. The proposal builds upon data from preliminary studies conducted in mice and non-human primates (NHPs), demonstrating the feasibility of AAV vector-mediated gene therapy for CysB, and sets the following three specific aims to achieve the goal. We will seek to discover AAV capsids that outperform the current benchmark capsid in PT transduction via RP delivery, while evading neutralizing antibodies (NAbs) and minimizing off-target transduction (Aim 1). We will optimize therapeutic payloads for AAV RP injection-mediated gene replacement therapy for CysB using a CysB mouse model (Aim 2). We will evaluate dose-response, biodistribution, and safety of optimized therapeutic AAV vector in NHPs to facilitate future clinical translation of AAV vector-mediated CysB gene therapy (Aim 3). Successful outcomes will provide a transformative therapy for CysB by targeting its root cause and eliminating the need for burdensome conservative measures, medications with side effects, and repeated surgical interventions. In addition, this work will have the potential to revolutionize treatment not only for other types of cystinuria but also for other kidney diseases affecting renal tubules, regardless of whether they have genetic or non-genetic etiologies.

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY With the most people ever in history currently living with HIV, stopping the HIV epidemic remains imperative. Combination antiretroviral therapy (ART) limits viral replication, but is not curative. Thus, there is an urgent need to design a functional cure via elimination of the viral reservoir. We recently found that the combination of antiretroviral therapy, broadly neutralizing antibodies, and CCR5 blockade were able to completely clear establishment of infection in newborn macaques when delivered by day three post-infection. However, it remains unclear how far post-infection this treatment window extends in newborns and if this treatment is also effective in adults. In specific aim 1, we will systematically identify the window of opportunity for this novel triple therapy treatment to clear the latent reservoir by delaying treatment multiple days. In specific aim 2, we will determine if this remarkable clearance of reservoir establishment via triple therapy is also effective in adults infected via sexual transmission. Because all three components of this triple therapy are currently being tested individually in humans, successful completion of the aims here will set the stage for clinical trials to for HIV cure.

NIH Research Projects · FY 2026 · 2026-06

Abstract. Recent advances in immune checkpoint inhibitor (ICI) based therapies have improved outcomes for many patients with advanced stage melanoma. Nonetheless, around 50% of patients do not respond to ICI therapies due to the immunologically 'cold' tumor microenvironment (TME) characterized by enriched immunosuppressive cells (e.g., regulatory T cells and tumor-associated macrophages) and cytokines that limit cytotoxic lymphocyte infiltration. Further, even for patients who respond to ICI, the response is often not durable. To address these challenges, we will develop an innovative nanotechnology approach utilizing multifunctional ultrasound- responsive nanoparticles (URNs) to enhance the outcomes of melanoma immunotherapies. URNs consist of a hydrophobically modified silica nanoparticle core and a peptide amphiphile (PA) stabilizing shell. The hydrophobic cores stabilize surface gas pockets, enabling strong cavitation activity under FUS treatment, thereby mechanically disrupting the tumor tissue and releasing immunostimulatory tumor antigens and danger- associated molecular patterns (DAMPs). In addition, we showed that intratumorally injected URNs significantly improved the tumor retention and cellular internalization of drugs conjugated to their PA shells through physical interactions of PAs with hydrophobic URN surfaces and cell membranes. In this proposal, we will leverage the multifunctionality of URNs by combining mechanical tumor ablation with sustained delivery of a Toll-like receptor 7/8 (TLR7/8) agonist, which can generate pro-inflammatory, anti-cancer responses. Accordingly, our central hypothesis is that the release of tumor antigens and DAMPs through ablation, combined with a durable pro- inflammatory tumor microenvironment driven by sustained TLR7/8 activation, will synergistically stimulate innate and adaptive immune responses capable of achieving curative outcomes. To achieve this overall goal, in the first Aim, we will optimize the FUS ablation conditions to maximize the innate and adaptive immune responses generated by URN-enabled tumor ablation. In the second Aim, we will test a rationally designed library of URNs with different hydrophobic modifications and PA coatings to optimize the sustained delivery of intratumorally injected TLR7/8 agonists, aiming to achieve and retain a pro-inflammatory TME without causing toxicity. Finally, we will combine URN-enabled ablation with TLR7/8 agonist delivery and evaluate its efficacy in multiple clinically relevant mouse melanoma models, including a spontaneous model. In summary, we propose developing a multifunctional nanomaterial platform for enhanced immunotherapy of melanoma. In addition, the approach described here may be used to deliver other adjuvant immunotherapies or applied to many other cancers, such as breast, prostate, and liver cancers, lending it broad utility across various cancer types.

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY Over 1 million women living with HIV (WLWH) give birth annually. With widespread use of combination antiretroviral therapy (cART), vertical transmission has been significantly reduced, resulting in ~16 million HIV- exposed uninfected (HEU) children as of 2023. Despite being HIV negative, these children face increased risks of poor growth, infection-related mortality, and respiratory disease. These outcomes are believed to result from maternal HIV-induced inflammation and/or cART toxicity, as many antiretrovirals cross the placenta and may disrupt fetal immune development. However, distinguishing the effects of HIV versus ART is difficult in clinical studies due to challenges of studying non-HIV infected women receiving ART. Limited access to fetal tissues further hampers mechanistic insight, creating a need for translational animal models. To address this critical knowledge gap, we propose to use a rhesus macaque model of simian immunodeficiency virus (SIV) infection to investigate how maternal HIV and long-acting ART (LA-ART) affect fetal immune development. We hypothesize that despite the absence of vertical transmission, maternal SIV and LA-ART exposure dysregulates immune ontogeny in the offspring via altered hematopoiesis. A novel LA-ART regimen of FDA-approved drugs Lenacapavir (LEN) and Cabotegravir (CAB), shown to provide effective viral suppression in preliminary macaque studies, will be given bimonthly by injection to female macaques that will then undergo time-mated breeding following viral suppression. Three experimental groups will be studied: [1] SIV-infected, LA- ART treated; [2] uninfected, LA-ART treated; and [3] uninfected, untreated controls. Offspring will be delivered naturally and monitored through six months of age. Specific Aim 1 will assess how maternal SIV/LA-ART versus LA-ART alone affects infant immune maturation and function in the periphery and in tissues using flow cytometry, single-cell RNA/ATAC-sequencing, and in vitro stimulation. We will evaluate vaccine responsiveness using Varivax™ and examine B/T cell responses and receptor repertoires. Specific Aim 2 will study the impact of maternal SIV/LA-ART versus LA-ART alone on hematopoiesis in the offspring. We hypothesize that SIV/LA-ART exposure impairs differentiation and maturation of hematopoietic stem and progenitor cells (HSPCs). Bone marrow will be analyzed via flow cytometry, differentiation assays, and single-cell RNA/ATAC-sequencing. Functional HSPC capacity will be tested via transplantation into immunodeficient mice. This study uses a clinically highly relevant primate model for HIV cure research and neonatal immunity, and advanced immunological tools to uncover how maternal HIV and LA-ART exposure alter infant immune development. Findings will guide future strategies to improve immune outcomes in HEU children.

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY The re-engineering of viral pathogens into vectors for biological discovery and human therapy has driven landmark advancements across biomedicine, including in neuroscience. However, the molecular principles through which viruses interact with diverse types of primary host cells in complex tissue are largely unknown, a knowledge gap that complicates the use and interpretation of virus-based tools. Rabies lyssavirus has played an important role in the defining the synaptic organization of the brain’s neural circuitry: Rabies evolvedto spread from neuronal dendrites to neuronal axons through synapses and has been engineered to restrict spread into just those presynaptic neurons making direct synaptic connections on molecularly-defined postsynaptic neurons, revealing “monosynaptic” networks in the intact brain through expression of fluorescent proteins. Another salient and unique infection property of rabies is the maintenance of “stealth”from innate immunesystem, accomplished in part by re-deployment of rabies proteins to physically sequester and thus antagonize key signaling nodes downstream of viral sensing and anti-viral responses. Virologists and immunologists have detailed the molecular mechanisms of innate immune antagonism by rabies proteins over decades in cell line and have revealed that the potency of antagonism tends to be genetically-eroded as rabies strains are adapted to cell culture. Because the two rabies strains currently used by neuroscientists for monosynaptic tracing are (to different degrees) cell culture adapted, experimentally-identified monosynaptic networks may be influencedby the innate immune state of infected neurons. Here, we propose to use a novel “toolbox” based on the minimally cell culture adapted “Tha” strain to establish 1) a potent novel vector for monosynaptic tracing (Aim 1) and 2) directly test the hypothesis that the innate immune state in postsynaptic neurons controls the degree of rabies presynaptic uptake (Aim 2). To do this, I will leverage a Tha variant carrying two point mutations in the viral phosphoprotein (2P) and four point mutations in the viral matrix protein (4M) that largely abrogate innate immune antagonism while leaving canonical viral functions in fact. By quantitative comparison of monosynaptic networks and single-cell molecular properties across Tha and Tha2P4M infected neurons, I will directly test the hypothesis that upregulated innate immune signaling in postsynaptic neurons actively restricts presynaptic rabies uptake and identify the viral “restriction factors" deployed by neurons to limit rabies uptake. My proposal will not only provide neuroscientists a novel, cutting-edge tool to accurately characterize the synaptic organization of neural circuits in vivo, but will also establish a first-in-kind link between neuronal innate immunity and viral infection properties, with broad implications for how neurotropic infection proceeds across diverse cell types that compromise the central nervous system.

NIH Research Projects · FY 2026 · 2026-06

Project Summary Oral commensal streptococci, particularly Streptococcus sanguinis (Ss), play a crucial role in maintaining immune balance and tissue homeostasis within the oral cavity. As early colonizers of dental biofilms, these bacteria contribute to immune system priming and regulate host responses to microbial communities. While generally associated with oral health, Ss also exhibits pro-inflammatory traits, highlighting a dual role in both promoting and modulating immune activity. Our preliminary data reveal that this duality is promoted through the release of extracellular membrane vesicles (EMVs), which influence host cell signaling, gene expression, and epithelial integrity. The overarching goal of this project is to define how Ss EMVs contribute to immune regulation, apoptosis prevention, and epithelial barrier maintenance. We hypothesize that EMVs serve as key molecular effectors of commensal function, and their production and activity are shaped by ecological and host-associated factors. Aim 1 will assess how environmental conditions and disease states influence EMV production and cargo using clinical Ss isolates. Aim 2 will investigate how Ss EMVs enter oral epithelial cells, trigger immune responses, and how specific EMV components mediate host interactions. Aim 3 will evaluate the ability of Ss EMVs to prevent pathogen-induced apoptosis and preserve epithelial integrity in both monolayer and 3D tissue models. This research will advance our understanding of streptococcal molecular commensalism, reveal mechanisms of EMV-mediated host protection, and establish a foundation for novel strategies to support oral health through microbial EMV-based therapies.

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY Controlled protein synthesis is key to regulating gene expression and by shaping the varying proteomes of individual cell populations, plays an important role in the development of specialized cell functions. Despite advances in assessing cell type-specific transcriptomes, methods to interrogate the nascent proteome of individual cell populations have not kept pace. Here, we will develop and optimize an innovative and powerful method that we recently pioneered to achieve rapid labeling of newly synthesized proteins with cellular resolution. Our chemical-genetic method combines a puromycin-based labeling strategy involving a caged form of OP-puromycin (OPP) called PhAc-OPP with ectopic expression of the enzyme penicillin G acylase (PGA) in any cell population of interest. PhAc-OPP is unblocked and converted to OPP by PGA by enzymatic phenylacetyl blocking group removal, thus allowing OPP labeling of newly synthesized proteins in PGA- expressing cell populations. We have achieved several important preliminary milestones in demonstrating the efficacy of this method, including cell type-specific protein labeling in mouse primary neurons. To advance this method we call POPPi (PGA-dependent OPP incorporation) toward translational profiling of complex tissue cell populations in vivo, we have generated a PGA transgenic Drosophila strain that can be mated to any cell-type specific driver of choice. The use of Drosophila harnesses the extensive range of genetic drivers available for achieving cell type specific expression in the fly CNS with the rapid scalability of fly populations to facilitate profiling of rare cell populations. Preliminary testing supports our ability to label and capture neuronal and glial cell populations within isolated Drosophila brain explants using this approach. The first major goal of the current study is to quantitatively profile labeled nascent proteomes from discrete brain cell populations using TMT tagging and LC-MS/MS. This will enable us to determine whether nascent proteomes captured from targeted cell populations are truly cell type-specific and of sufficient depth to have utility in future biological applications of the method. A second goal of the study is to develop and optimize a dietary PhAc-OPP ingestion approach for proteome labeling. If successful, the ability to administer PhAc-OPP dietarily will elevate utility of the method by demonstrating its suitability for assessing the effects of physiological or pathological stimuli on translation that can only be applied to an intact fly. Collectively, this work forms key milestones in evaluating the potential for applying POPPi to quantitative profiling of the nascent proteome following physiological or pathological stimuli.

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY Sugar-sweetened beverage (SSB) consumption is a key contributor to obesity, diabetes, and cardiovascular disease (CVD) in the U.S. Seven U.S. municipalities have implemented SSB excise taxes to reduce consumption, yet the downstream impact of these taxes on diabetes and cardiometabolic health remains unknown. This study will leverage longitudinal electronic health record (EHR) data from the OCHIN network—a large, multi-state consortium of community health centers (CHCs)—to evaluate whether SSB excise tax implementation is associated with improvements in commonly assessed diabetes and cardiovascular risk biomarkers in real-world primary care settings. Using a quasi-experimental difference-in-differences design, we will compare changes in biomarker outcomes from pre- to post-tax periods in taxed versus matched non-taxed municipalities. We will also examine whether these effects differ across key individual-level subgroups, including by age, income, language preference, and food insecurity status. This work addresses a critical evidence gap regarding the health impacts of SSB taxation among low-income populations and will inform local, state, and national policy efforts, including proposals to restrict SSB purchases through SNAP. By evaluating clinical outcomes in the context of real-world tax implementation, this study will provide actionable insights into how policy interventions may influence diabetes and cardiometabolic health at scale.

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY Astrocytes are essential regulators of the nervous system and the vast majority of astrocyte functions in health and disease have been linked to intracellular calcium signaling. This includes the newly recognized participation of astrocytes in neuronal circuits, a level of regulation of neuronal firing largely ignored in our connectome- and electrophysiology-based understanding of brain function. Nevertheless, while decades of research have characterized the input/output relationships of neurons and how they impact circuit function, few studies have explored the rules that govern when astrocytes respond to different neurotransmitters in vivo and how they affect downstream circuit modulation. I previously discovered a mechanism by which an arousal- associated tyramine cue can change which neurotransmitters induce calcium influx in astrocytes. Specifically, I showed that tyramine can “gate” the ability of astrocytes to respond to dopamine by decreasing cAMP concentrations and inhibiting a pathway that internalizes receptors from the plasma membrane. Further, I found that gated dopamine responses can control downstream neuronal activity, demonstrating the power of astrocytes over neuronal circuits. However, key mechanistic questions remain about this newly discovered mechanism. During the mentored award phase, I will learn new approaches to dissecting astrocyte neuromodulation in mice while also developing new tools in Drosophila to manipulate gating in vivo. I will then take these skills to my own laboratory, where I will gain mechanistic understanding of how gating occurs and what impact it has on downstream circuits. In Aim 1, I will delineate the key regulators of dopamine receptor externalization to better understand how gating in astrocytes can affect circuit computations and behavior. In Aim 2, I will use the control of neuronal activity downstream of gated dopamine responses to dissect how astrocytes change neuronal activity and what neurons they can control. In Aim 3, I will translate this gating mechanism to mice, characterizing how dopamine response gating occurs across the mammalian brain, developing new tools to modulate that gating in mice, and determining how gating changes in the context of disease. Together these aims will reveal greater mechanistic detail of how gating occurs and how it impacts the computations that astrocytes perform in the brain. To complete these aims, I have outlined a series of research and career development milestones to prepare me for a successful research career and formed an advisory committee of world-leading scientists committed to mentoring me through my transition to independence. My overarching career goal is to head an independent research lab that combines the genetic power of Drosophila with the circuit complexity of rodents to uncover the fundamental molecular mechanisms of glial cell function and how they change in disease.

NIH Research Projects · FY 2026 · 2026-06

ABSTRACT Intestinal epithelial cells (IECs) are a frontline cellular barrier encountered by potentially infectious enteric microbes, and are central players in maintenance of homeostasis with commensal microbes in the gut. Dietary, genetic, and environmental factos can regulate the magnitude of immune responses at this barrier surface throughout life, and improper regulation of these responses can trigger pathological inflammation or disease. Therefore, it is important to understand mechanisms by which dietary and developmental factors regulate IEC-intrinsic immune responses. Interferon (IFN) family cytokines are major components of the antimicrobial immune response. Prior studies have found that a specialized type of IFN cytokine called IFN-λ (also known at type III IFN) is necessary and sufficient for defense of IECs from viral infections in mouse models and human IEC cultures. We recently found that homeostatic IFN-λ responses are amplified in IECs of neonatal mice, but the stimuli that are responsible for this amplification remain unclear. Our new unpublished studies find that milk amplifies IFN-λ responses in a human neonatal IEC organoid model. This exploratory proposal aims to validate and extend these findings in human organoid and mouse models. Our central hypothesis is that a bioactive component of raw human milk amplifies the IFN-λ response to protect neonates from enteric viral infections and promote intestinal homeostasis. We will test this hypothesis through the following aims. Aim 1: Define the mechanism by which raw human milk amplifies the IFN-λ response. Aim 1.1 Define the IFN-amplifying biochemical fraction of raw milk. Aim 1.2 Determine the signaling pathways required for IFN-enhancement by raw milk. Aim 2: Determine the role of milk in driving the homeostatic IFN-λ response in mouse models. Aim 2.1 Determine the effect of raw milk on the neonatal homeostatic IFN-λ response. Aim 2.2 Test the role of raw milk in promoting an antiviral response in the neonatal rotavirus model. This project will establish a novel role for milk in amplifying IFN-λ receptor signaling activity in IECs, increasing our understanding of intestinal homeostasis and resistance to viral infection in the neonate intestine.

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY There is robust evidence from human studies that support that pregnancies utilizing programmed, i.e., medicated frozen embryo transfers are at higher risk for several adverse maternal and fetal outcomes. While it has been postulated that these adverse outcomes originate from the lack of a functional corpus luteum (CL) during pregnancy, this has yet to be directly tested. This current gap in knowledge is likely due to the lack of a suitable animal model. Our proposed collaborative project will address this need, utilizing two novel non-human primate models that allow direct examination of first trimester CL and placental development. The main objective of this innovative application is to test the hypothesis that both the increased level of exogenous estradiol and the lack of a CL which occur in programmed cycle FET (p-FET) synergistically cause molecular changes in the early placenta development that predispose adverse pregnancy outcomes. To test this hypothesis, we will conduct in- depth placental phenotyping and molecular assessments to determine the cellular and molecular changes with p-FET in the first trimester placenta (Aim 1). We will also directly assess the protein and small molecules secreted into maternal circulation by the CL during the first trimester using cutting edge high throughput methodology to detect even low abundant molecules in CL and maternal blood samples (Aim 2). The Aims outlined in this application will provide extensive information for the field by improving understanding of how placental development is influenced by estradiol levels and other CL molecule signaling during the first trimester. Determining the causes of pregnancy loss, and pregnancy complications would greatly improve human health, reducing the associated physiological, psychological, and economic burdens and help us shape advances in maternal-fetal medicine.

NIH Research Projects · FY 2026 · 2026-05

Project Summary Interoception, the neural representation of the body’s internal state, is critical to health and survival. Despite its importance for animal wellbeing, the precise central circuit mediating interoception remains largely unknown. The insular cortex, a key hub for interoception, is known to integrate external and internal sensory signals with higher order processes. However, while the circuits driving external (e.g. auditory, visual, somatic) sensory pro- cessing are extensively studied, those for internal sensations and which mediate their integration in the insula remain largely elusive. Thus, our lacking knowledge of the central substrates that convey internal sensations has delimited our understanding of and therapeutic advancement for interoceptive disease states, like anorexia and anxiety. To this end, this proposal aims to uncover the subcellular and mesoscale circuit organizations for taste and visceral sensory integration and link these two internal sensory circuits to their behavioral functions. First, I will determine how taste-sensing neurons of the parvicellular ventroposterior medial thalamus (VPMpc) and visceral-relay neurons of the external lateral parabrachial nucleus (PBNel) organize their synaptic inputs across the dendritic subdomains of pyramidal neurons within the posterior insula. Then, I will assess the ne- cessity of the PBNel-to-insula circuit in conditioned taste aversion, an interoceptive behavior. Finally, I will iden- tify the input brain regions that drive two insula-converging neuronal populations to determine the broader cir- cuit architecture for internal sensory processing. My central hypothesis is that distinct subcellular and mesoscale circuit architectures through the VPMpc and PBNel subserve taste-visceral integration within the insula and drive aversion behavior. To test this hypothesis, I will learn subcellular channelrhodopsin-assisted circuit mapping and whole cell patch clamp electrophysiology to compare the functional synaptic organizations of VPMpc or PBNel inputs onto insular pyramidal neurons. I will then use circuit-specific ablation of synaptic transmission with tetanus toxin to evaluate the role of insula-projecting PBNel neurons in conditioned taste aversion. Finally, I will learn pseudotyped rabies-mediated viral tracing to label upstream populations impinging on VPMpc-to-insula and PBNel-to-insula circuits, thus elucidating polysynaptic architectures for internal sen- sory systems in the brain. Achieving these aims will provide novel insight into how insular neurons receive and integrate taste and visceral information to affect behavior, and lay the foundation for future investigation into the central interoceptive system. This project will complement a comprehensive training plan that I have devel- oped with my mentor, Dr. Tianyi Mao. In addition to advanced training in technical methodology, I will enhance my skills in programming, experimental design, and quantitative analysis. I will also deepen my understanding of central sensory processing and interoception research. Finally, I expect to engage in activities that will de- velop my skills in scientific communication. The proposed training will position me to succeed as an independ- ent researcher and leader in academic research.

NIH Research Projects · FY 2026 · 2026-05

Project Summary Neonatal white matter injury (NWMI) is a major cause of motor and cognitive abnormalities in infants born pre- term, as well as in term births with complications such as intrauterine growth restriction, placental abruption, and birth asphyxia. Cerebral hypoxia and altered fetal circulation cause myelination defects in these conditions. However, the underlying mechanisms that disrupt the myelination by oligodendrocytes in hypoxic-ischemia are not completely clear. Myelination is a metabolically demanding process, requiring adequate vascularization, blood flow and oxygen content, all which can be compromised in pre-term or term birth with complications leading to NWMI. The central objective of this proposal is to understand how oligodendroglia obtain metabolic support from the white matter vasculature in normal development, and how this process is affected in neonatal hypoxic- ischemic brain injury. We recently demonstrated that oligodendroglial progenitor cells (OPC), an early precursor of the myelin forming oligodendrocytes, orchestrate white matter angiogenesis. This project aims to uncover a previously undefined mechanism involving endothelial-apelin signaling, which metabolically supports white matter vascularization and myelination. We propose to use various genetic and pharmacological strategies to (1) dissect out the mechanism of how OPCs regulate endothelial-apelin signaling in normal development and after neonatal hypoxic-ischemic (H-I) injury. (2) Next, understand how this process regulates cerebrovascular- tone, glucose uptake and vascularization in normal development and after neonatal H-I injury. (3) Finally, we will determine how brain wide hypoglycemia affects myelination and oligodendrocyte-metabolic pathways in normal development and after neonatal H-I injury. Together, these three aims will explore the metabolic crosstalk between oligodendroglia and endothelium and can provide insights into the protective mechanisms against disturbances in cerebral blood flow and oxygen delivery. The knowledge gained from these studies could result in potential therapeutics that might benefit the long-term neurodevelopment of children affected by neonatal hypoxic-ischemic brain injury, pediatric stroke, preterm birth, and other significant birth complications targeting the developing brain.

NIH Research Projects · FY 2026 · 2026-05

Project Summary Astrocytes respond to neuronal activity via various neurotransmitter receptors, triggering intracellular calcium increases in astrocytes that are both necessary and sufficient to induce changes in neural circuit activity and behavior. Substantial evidence from several model organisms has suggested that purinergic signaling is required downstream of astrocyte calcium events, supporting the idea that ATP is released from astrocytes, broken down to adenosine, and then signals to neurons through adenosine receptors to regulate neural circuit function. However, we still do not understand the precise mechanisms by which ATP may be released. To investigate how ATP and adenosine may be involved in astrocyte regulation of neural circuits, I performed preliminary experiments in Drosophila using ex vivo live imaging of a fluorescent biosensor of extracellular ATP expressed in astrocyte membranes. In contrast to the predictions of the current model of astrocyte neuromodulation, induction of calcium activity in astrocytes via bath application of neurotransmitters did not result in increases in extracellular ATP. However, I did observe ATP events evoked by neuronal activation with K+ bath application or electrical stimulation. These events were blocked by the pannexin/innexin blocker, probenecid. I will build on these preliminary results by investigating the signals that lead to ATP release and identifying the molecule responsible for induced ATP release. In Aim 1, I will block synaptic release and astrocyte calcium elevations to determine if either is required for ATP release. I also will perform chemogenetic activation of neuronal subtypes (e.g. glutamatergic, GABAergic) to determine which (if any) are responsible for inducing ATP release. I also will use primary astrocyte cell culture to evaluate if astrocytes have cell-type intrinsic responses to K+ elevations. In Aim 2, I will use cell-type specific genetic knockdown/knockout of known targets of probenecid, members of the Innexin gene family, in combination with live imaging to identify the molecule responsible for induced ATP release in the fly brain. Under the mentorship of Dr. Marc Freeman and aided by the fantastic intellectual and material resources available at the Vollum and OHSU, I will gain additional technical expertise in live imaging as well as developing new skills in cloning and transgenesis, and culture of mammalian astrocytes. I will also further my skills in scientific communication, leadership, and teaching and mentorship. This training plan will provide abilities crucial for me to reach my long-term goal of becoming an independent researcher studying the fundamental signaling mechanisms in the brain. The proposed research plan will provide a new mechanistic understanding of how ATP and adenosine signaling – the primary means by which astrocytes regulate neuronal activity – is regulated in vivo. Given the deep conservation of astrocyte neuromodulation and adrenergic signaling from flies, to zebrafish to mouse, I expect my work will provide important new insights into astrocyte adrenergic signaling in the human brain.

NIH Research Projects · FY 2026 · 2026-05

Project Summary In the central nervous system (CNS), commencement of myelination begins with oligodendrocyte precursor cells (OPCs) differentiating into mature oligodendrocytes (OLs) that produce myelin. During myelination, OPCs undergo a 6500-fold membrane expansion and substantial proteolipid synthesis. This requires significant metabolic resources, which are met by a complex cerebrovascular network that supply OPCs with metabolites and oxygen. The cerebrovascular network is formed through sprouting angiogenesis, growth of new blood vessels from existing vasculature, led by endothelial tip cells. Endothelial tip cells are specialized migrating cells, and are highly glycolytic to meet their metabolic demands associated with rapid remodelling of their cytoskeleton to migrate and fuse with the neighboring tip cells to form functionally perfused blood vessels. Notably, during postnatal development the timecourses for commencement of myelination and sprouting angiogenesis overlap. This raises the possibility for metabolic coordination between these processes. However, our understanding of how oligodendrocyte lineage cells interact with the vasculature remains incomplete. We know that OPC interact physically with endothelial tip cells. My preliminary data shows hypoxia inducible factor (HIF) activity within OPCs promotes endothelial tip cell-Glut1 expression and neoangiogenesis. Genetically blocking Glut1 within CNS endothelium specifically also caused myelination deficits. These findings support my central hypothesis that OPC-intrinsic HIF signaling regulates endothelial tip cell-Glut1 mediated glucose uptake, which metabolically supports vascularization and myelination during development and promotes repair post neonatal hypoxic brain injury. I will test this hypothesis in the following aims: For my first aim, I will utilize OPC-intrinsic HIF mutant mouse models alongside ex vivo slice cultures, immunohistochemical (IHC), electron microscopy (EM) and smFISH analysis to characterize changes in OPC-vascular and endothelial tip cell interactions and tip cell-Glut1 levels and cortical and white matter glucose levels. For my second aim, I will employ a tip cell-specific Glut1 conditional knockout model, along with laser speckle contrast imaging and compound actional potential recording techniques to understand how cerebral vascularization, blood flow and myelination are functionally regulated through glucose mediated metabolic support in normal development and after hypoxic injury. These powerful models and combinatorial use of in vivo and ex vivo approaches outlined in this study will shed light on the metabolic crosstalk between OPCs and endothelial tip cells.

NIH Research Projects · FY 2026 · 2026-05

Project Summary This project seeks to understand the neurophysiological basis of binaural fusion in the auditory system. When interacting with the world, humans and other animals must process sound information arriving from multiple different sources. Depending on the location of a sound source, the signals reaching the two ears will differ, and the auditory system uses these binaural cues to determine sound location. When multiple sound sources are present, the auditory system also uses binaural information to determine if sound features belong to the same or different source. When sounds reaching the two ears have similar spectral and temporal properties, they are typically fused and perceived as belonging to a single source. In patients with hearing loss, binaural fusion can occur over a wider range of binaural differences, and multiple sources can be incorrectly fused and perceived as belonging to a single source. Using a combination of behavioral and neurophysiological approaches, this study will determine the conditions under which humans and animals experience binaural fusion and the neural mechanisms that support these percepts. A critical aspect of this work that enables linking human and animal behavior is the development of new, objective behavioral measures of binaural fusion. The first set of experiments will use this objective behavioral approach to determine factors that lead to fusion of binaural spectral information in humans and animals. It will then use high-channel count, single-unit neurophysiological recordings to characterize the neural representation of fused and segregated stimuli. The second set of experiments will use a similar approach to determine neural correlates of fusion of temporal sound modulations. The third, and final experiments will measure the neural response to large sets of natural binaural stimuli. It will then fit a deep learning-based encoding model to describe the neural response to any arbitrary binaural sound. This model will be validated against its ability to predict neural responses to fused and non-fused stimuli. It will then be used to synthesize novel stimuli that are predicted to produce a fused percept in human subjects. Understanding the conditions under which fusion occurs and the neurophysiological mechanisms that mediate fusion will provide insight into perceptual deficits following hearing loss and can be used to guide the development of new treatments that reduce abnormal fusion.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY Alport Syndrome (AS) is a monogenic disease primarily caused by a deficiency of functional type IV collagen a chains (COL4A3/4/5), matrix proteins that play a crucial role in maintaining the structural integrity of basement membranes in the kidneys, ears, and eyes, leading to progressive chronic kidney disease (CKD), hearing loss and ocular impairment, respectively. Although all three manifestations in this triad are equally devastating and diminish the quality of life for affected individuals, kidney involvement is particularly severe and often life- threatening. Importantly, AS is the second most prevalent genetic kidney disease that leads to CKD and, ultimately, kidney failure (KF). Despite its relatively high prevalence among the rare genetic diseases, estimated to be 1 in 2,000 to 5,000 people, current clinical pharmacological therapy for AS-related CKD is limited to the treatment with angiotensin-converting enzyme inhibitors, which only partially delays the progression of CKD. Currently, there is no curative therapy for the disease. Therefore, there is an urgent, unmet need for innovative and more effective CKD therapies for AS. In recent years, significant progress has been made in the field of adeno-associated virus (AAV) vector-mediated gene therapy for monogenic diseases, leading to the approval of commercial products. Despite the immense potential of AAV vectors to treat genetic diseases and the compelling nature of genetic kidney diseases, including AS, as gene therapy targets, AAV vector-mediated gene therapy for genetic kidney diseases has remained underexplored. This is primarily due to the challenge in effectively delivering genes to the kidney even with AAV vectors. Moreover, AAV gene therapy for AS faces an additional challenge in that the size of the therapeutic gene payload encoding COL4A3, COL4A4, and COL4A5 chains exceeds the packaging capacity of AAV vectors. In this regard, notably, the Nakai (PD/PI) lab has recently achieved a breakthrough by devising a novel AAV vector approach that can mediate effective expression of the full-length COL4A5 protein in podocytes and allows its expression, secretion, and deposition in the glomerular basement membrane in the kidneys of AS mouse models. This breakthrough has warranted assessment of its efficacy using clinically relevant large animal models. While non-human primate models for AS do not exist, a well-established AS dog model is available, the X-linked AS (XLAS) dog model that has been extensively studied and maintained by the Nabity (MPI) lab. Given this background, this collaborative, exploratory multi-PI project between the Nakai and Nabity labs aims to demonstrate proof of concept of AAV vector-mediated gene therapy for AS in an XLAS dog model and investigate AAV vector biology, pharmacokinetics, biodistribution, off-target effects, and immune responses in this dog model. Success in the project will significantly spur the development of AAV gene therapy for AS and further our knowledge of AAV vector biology in the AS context, which is essential for successful clinical translation. Furthermore, the project outcomes will have substantial implications for the treatment of other CKDs, whether of genetic or non-genetic etiologies.

NIH Research Projects · FY 2026 · 2026-05

Project Summary: Neurodevelopmental disorders, including syndromic disorders of retinal and brain development, are a major cause of morbidity in children. A subset of these disorders results from abnormal vascular development, and microcephaly and chorioretinopathy (MCCRP) is a recently identified disease that may belong in this category. It is characterized by small head circumference, brain anomalies, developmental delay, and vision loss due to chorioretinopathy and abnormal retinal vasculature. Autosomal recessive MCCRP results from defects in TUBGCP4 or TUBGCP6, which encode components of the gamma-tubulin ring complex (γ-TuRC), a ubiquitous structure necessary for microtubule nucleation and spindle formation in cells. However, γ-TuRC has not previously been implicated in vascular development and it is unknown why defects in γ-TuRC lead to blindness and microcephaly. We demonstrated that Tubgcp4 and Tubgcp6 expression is highly upregulated in murine vascular endothelial cells (EC) from the retina and brain (relative to EC from other tissues), and that murine EC deficiency of TUBGCP4 results in embryonic lethality, indicating a critical role for TUBGCP4 in EC. Our long-term goal is to identify the role of the γ-TuRC in retinal and brain development. The objective of this application is to define the pathophysiology of TUBGCP4 and TUBGCP6-associated MCCRP. We will test the hypothesis that TUBGCP4 and TUBGCP6 serve critical, EC-specific roles in the retina and brain, and that deficiency of these proteins results in MCCRP due to a primary vascular developmental defect. Since retinal and cerebral vascular development is not complete until several weeks after birth, we will use novel conditional knockout mouse models of Tubgcp4 and Tubgcp6 and a tamoxifen-inducible EC-specific Cre recombinase to eliminate expression of these genes in EC postnatally. Ophthalmic studies will demonstrate the necessity of EC-specific TUBGCP4 and TUBGCP6 in retina and retinal vascular development, including optical coherence tomography (OCT), OCT-angiography, electroretinogram, optokinetic response, and retinal histology (Aim 1). Neurologic studies in mice and/or embryos lacking TUBGCP4 or TUBGCP6 in EC will demonstrate the necessity of these proteins in cerebral and neurovascular development, including MRI brain imaging, neurobehavioral studies, and brain immunohistochemistry (Aim 2). Elucidating the pathophysiology of MCCRP will improve our understanding of the genetic mechanisms controlling retinal and brain vascular development, and may reveal new therapeutic targets for more common blinding retinal vascular diseases. The career development objective of this proposal is to develop the mentorship and expertise needed to become a productive independent clinician-scientist and international leader working at the intersection of inherited retinal diseases (IRD) and disorders of vascular development. OHSU is a center of renowned expertise in IRDs, in vivo retinal vascular imaging, and the neurosciences; it provides state of the art resources and world-class faculty to support Dr. Everett’s scientific and career development goals for this proposal.

NIH Research Projects · FY 2026 · 2026-05

PROJECT ABSTRACT The thick ascending limb (TAL) of the nephron plays a central role in sodium and potassium homeostasis, but its ability to adapt to dietary potassium stress remains poorly defined. Preliminary data indicate that the inwardly rectifying potassium channel Kir4.1 is selectively expressed in distinct TAL cell populations and may function as a basolateral potassium sensor. This career development proposal tests the hypothesis that Kir4.1 regulates TAL transport and drives structural and transcriptional remodeling in response to changes in extracellular potassium concentration that accompany extremes of dietary potassium intake. To test this hypothesis, the research integrates TAL-specific Kir4.1 knockout models with advanced imaging, metabolic phenotyping, tubule perfusion, and single-nucleus RNA sequencing. Aim 1 tests the hypothesis that Kir4.1 enables basolateral potassium sensing and thereby regulates TAL sodium and potassium handling. Aim 2 tests the hypothesis that Kir4.1-expressing TAL cells undergo structural and transcriptional remodeling— including phenotypic switching, apoptosis, or proliferation—in response to extreme dietary potassium stress. These studies aim to close a key knowledge gap in segment-specific potassium sensing and may reveal new therapeutic targets for hypokalemic disorders and diuretic resistance. The candidate’s long-term objective is to lead an independent research program focused on renal epithelial transport in genetic and acquired tubulopathies. This K08 award will provide the mentored training necessary to support this transition, with structured development in electrophysiology, high-resolution imaging, and transcriptomic analysis. The training environment at Oregon Health and Science University offers strong mentorship, institutional support, and access to leading expertise in renal physiology to foster the candidate’s development as a physician-scientist.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY / ABSTRACT Predicting drug perturbation effects on primary patient samples is a core translational problem critical for effective patient treatment. Single-cell high-throughput technologies enable the study of drug effects on heterogeneous cell populations, capturing patient-specific variability in disease mechanisms and treatment response. While unimodal and multiomic single-cell platforms offer unprecedented resolution, they introduce new challenges for AI/ML models. High cell input requirements and destructive measurement protocols limit patient profiling, especially in the context of combination therapies, where the number of possible drug regimens grows exponentially. Most datasets also lack paired measurements of pre- and post-treatment states, complicating efforts to model cellular heterogeneity and subpopulation dynamics under perturbation. Furthermore, clinically relevant datasets with long-term treatment effects remain scarce. There is a critical need for computational approaches that generalize across unseen drugs and patients, and that can integrate across assays, cohorts, and scales—from bulk to single-cell. We propose to address these needs through novel computational approaches that span two independent research directions. In the first, we propose a principled approach that leverages emerging technologies to predict drug response at a single cell resolution, including of previously unseen mono- and combination therapies and in new patients. Our model combines cell state prediction, causal regularization, and distributional alignment that aims to blend data-driven learning with known mechanisms. In contrast to current methods, the proposed approach will be grounded with a reference dataset that will (i) provide paired perturbed and non-perturbed cellular measurements to precisely establish cell state transitions including cell death and persistent states, and (ii) will measure long term drug treatment effects more closely resembling clinical regimens. In the second direction, we propose a unifying transfer learning framework for drug response prediction, that enables the integration of data across multiple patient cohorts, modalities, and scale. This proposal aims to uncover drug response mechanisms at single-cell resolution to advance the development of combination therapies that overcome resistance. We will deliver a validated computational framework that models cell state transitions under perturbation, using novel AI-based methods and a time- resolved ex vivo reference dataset. Our approach maximizes the value of limited patient material and enables scalable, platform-independent analysis across diseases and treatments. Importantly, the framework supports federated learning across institutions, allowing model training on decentralized data while preserving patient privacy. This work is in strong support of the mission of NIGMS for advances in disease diagnosis, treatment, and prevention.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY Health care authorities including The US Preventive Services Task Force, American Academy of Pediatrics, and American Academy of Family Physicians recommend that primary care clinicians screen for Electronic Nicotine Delivery Systems (ENDS) use and talk with patients about the potential harms of use. Studies have found that assessment of ENDS use in primary care settings is low, (ranging from 1-34%). Findings about patient characteristics associated with ENDS use assessment are mixed, and studies are limited to individuals ≥18, users of combustible tobacco (CT), or reports from clinician surveys. Primary care is an important source of information and assistance for tobacco cessation, but nearly half of clinicians report lacking knowledge and confidence to talk with patients about ENDS use. This is important because recent studies show that about 60% of both young people and adults report wanting to quit ENDS use. We currently have little insight about the frequency with which ENDS use cessation assistance is offered to primary care patients who wish to quit ENDs use. Understanding current practices and patient, clinician and health care setting factors associated with ENDS use assessment and cessation assistance documentation can inform opportunities and strategies for improvement. We propose a mixed methods study of 22 primary care clinics providing care to more than 154K patients. This study aims to identify the current assessment and electronic health record documentation of ENDS use among 12+ year old primary care patients and examine patient, provider and clinic characteristics associated with both ENDS use assessment and offers of cessation assistance for those who want to quit. Guided by the Consolidated Framework for Implementation Research (CFIR) and the Exploration, Preparation, Implementation, and Sustainment (EPIS) framework, this study also uses a series of Community Engagement Studios to ground our understanding of the key challenges and opportunities. Collectively, we aim to generate stakeholder-centered recommendations for embedding ENDS use assessments into workflows and to identify the needs and strategies to prepare for, adopt and implement guideline-based ENDS cessation assistance. This study will inform current practices to assess ENDS use and offer cessation assistance; identify multi-level factors associated with assessment and assistance; and establish data- and experience- informed solutions generated by primary care and patient stakeholders faced with these challenges. Our study will also inform the development of implementation strategies for the routine assessment and discussion of the risks of ENDS use, and provision of cessation assistance for those who want to quit.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY On June 24-26, 2026, the 20th Northwest Reproductive Science Symposium (NWRSS) meeting will be held at the Best Western Plus Hood River Inn and Conference Center in Hood River, Oregon and hosted by the Oregon National Primate Research Center (ONPRC), which is a part of Oregon Health & Science University (OHSU). This long-standing meeting began in 1989 as the Washington State University (WSU) and the University of Idaho (UI) annual joint mini-symposium, but now organization and hosting rotates biennially between WSU/UI, Oregon State University (OSU), and ONPRC/OHSU. The NWRSS scientific program showcases reproductive science- related research being conducted primarily in the Pacific Northwest region and includes topics such as fertility and contraception, developmental biology, reproductive aging, environmental toxicology, and disease therapies to improve human reproductive and developmental health. Our overall objective is to promote the exchange of scientific information in an informal setting to advance our understanding of important events that occur throughout the entire life process. NWRSS organizers and participants remain committed to providing a safe and professional environment to foster the sharing of ideas and are pleased to welcome basic scientists, clinicians, and other leaders working in the reproductive or developmental biology field to the meeting. Because most of the attendees have historically been trainees, the NWRSS provides unique networking opportunities for undergraduates, graduate students, and postdoctoral fellows to interact with other trainees, early-stage investigators, and established scientists. NWRSS also seeks to support career development at multiple levels with encouraged participation from trainees in all aspects of meeting organization. To help facilitate this, an ad hoc trainee committee is established each year with representatives from all participating universities to oversee abstract submission and serve as session chairs during the meeting. Similar to previous years, at least one preeminent leader in the reproductive sciences will deliver a keynote address with additional prominent speakers invited from each university or chosen from the submitted abstracts. Due to shared interests in reproductive physiology and the relatively close proximity of attendees, many lasting and productive collaborations have arisen from these gatherings, and this is expected to continue at the 20th NWRSS meeting.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY To survive and thrive, bacteria must rapidly interpret complex sensory inputs and respond strategically. Central to this adaptability is the RNA degradosome, a crucial multi-protein complex that governs global RNA regulation. Our research on Streptococcus mutans, the dominant species associated with dental caries risk, reveals a surprising diversity of proteins interacting with the degradosome. We propose these are "moonlighting" proteins, serving as dynamic signaling or accessory factors that manipulate RNA targeting by the degradosome in real- time. This elegant system allows bacteria to efficiently and precisely coordinate cellular physiology with global posttranscriptional gene regulation. Our project employs a multidisciplinary approach, integrating genetics, advanced mass spectrometry, next-generation sequencing, cryo-electron microscopy, and innovative interspecies biofilm models. We aim to precisely map how the degradosome achieves its targeting specificity. In addition to advancing our understanding of fundamental genetics, another key objective is to exploit the degradosome as a strain-specific therapeutic target. By disrupting critical moonlighting interactions within the degradosome, it may be possible to deplete S. mutans in the oral cavity - a much-needed strategy to combat the global burden of dental caries. This work will reveal the structural and mechanistic mysteries of the S. mutans degradosome through the following three core objectives: i) unravel the role of moonlighting protein interactions and transcript targeting by the degradosome, ii) develop a mechanistic structural and biochemical model of a degradosome-substrate complex, and iii) assess the biological consequences and therapeutic potential of inhibiting protein moonlighting interactions with the S. mutans degradosome.

NIH Research Projects · FY 2026 · 2026-05

Project Summary Leishmaniasis, a disease caused by Leishmania parasites, poses a significant public health threat worldwide, and its reach is expanding to include parts of the United States. Treatment options remain limited, and the increasing emergence of drug-resistant parasites threatens the long-term effectiveness of existing therapies. Miltefosine, the only oral drug approved for leishmaniasis, is critical for treatment but increasingly compromised by resistance. The molecular mechanisms underlying miltefosine action and resistance remain poorly defined, limiting progress in combating treatment failures and developing more effective interventions. This project aims to address key gaps in our understanding of miltefosine resistance by leveraging advanced functional genomic tools developed in our laboratory. As proof of concept, we performed a pilot screen for miltefosine resistance in Leishmania using an inducible expression library of ~4000 open reading frames (ORFs) from the related parasite Trypanosoma brucei (the TbORFeome). We identified ZC3H18, an RNA-binding protein (RBP), as a novel resistance factor, making it the first RBP experimentally validated to mediate drug resistance in kinetoplastid parasites. This discovery highlights post-transcriptional regulation as a new, underexplored mechanism of antileishmanial drug resistance. In Aim 1, we will define the pathways regulated by Leishmania ZC3H18 to understand how it mediates miltefosine resistance. Building on our success with the TbORFeome library, we have developed a genome-scale, barcoded inducible overexpression library covering ~8,000 L. donovani genes (the LdORFeome). This library represents a major advance in Leishmania genetics, featuring near-complete coverage of protein coding genes, robust expression control through a novel split-Cre recombinase system, and an integrated barcoding platform for high- throughput analysis. In Aim 2, we will screen the LdORFeome library to uncover additional miltefosine resistance genes, which could provide a deeper understanding of the drug's mode of action. This work will uncover novel genetic determinants and regulatory pathways involved in miltefosine resistance, provide new insight into drug mechanism, and establish a versatile functional genomics platform for Leishmania. The findings have the potential to inform clinical strategies and support the development of next- generation therapies for leishmaniasis.