Molecular Mechanisms Drive Metabolic and Lipid Profiles that Define Cells in the Latent and Lytic Stages of Viral Infection - SUMMARY Metabolic modulation is critical to maintaining cellular homeostasis and viability throughout the life of a cell. However, there is a fundamental gap in knowledge regarding the molecular mechanisms that drive and rewire metabolic pathways in response to cellular perturbations such as viral infection. Viruses commandeer and manipulate basic cellular biology to persist and reproduce. Long-term viral persistence (latent stage) and active reproduction (lytic stage) depend on different alterations in fundamental cellular mechanisms, making a viral- host cell model system ideal to investigate how cellular metabolism is rewired to maintain cellular homeostasis. Work proposed in this MIRA ESI application will leverage our in vitro model system of herpesvirus infection that models both latent and lytic infection to define novel cellular mechanisms by which cells in the latent and lytic stages control metabolic regulation. The overall objective is to conduct an integrative analysis of the metabolic, lipid, and transcriptional profiles that define how latent and lytic stages of herpesvirus infection have evolved to maintain metabolic homeostasis. My central hypothesis is that specific metabolic signatures distinguish cell subpopulations that display differential survival between long-term latent stages and the acute lytic stages of infection. The rationale for this proposal is that the molecular and cellular mechanisms that are responsible for controlling metabolic changes during the progression of viral infections remain undefined. Based on preliminary data and established tools from our research team and established collaborations, I will test my central hypothesis by pursuing three major questions in the laboratory: (1) Which alterations in central carbon metabolism define the heterogenous cell populations in the latent and lytic stages? (2) What are the lipid profiles of heterogeneous subpopulations in the latent and lytic stages? and (3) How do cells in the latent and lytic stages modify their transcriptional profiles in each subpopulation to control metabolism? By answering these major questions, my team expects to identify previously unknown alterations in fundamental cellular biology and uncover novel mechanisms of cellular metabolic control. The research proposed for each research question will use technically innovative methods including mass spectrometry imaging (MSI) analysis for spatial metabolomics and spatial lipidomics, single-cell RNA sequencing, and spatial RNA sequencing to define the transcriptional profile across heterogenous cell populations. Our research will advance our understanding of the control of fundamental cellular metabolic pathways using a model of herpesvirus infection which allows us to pin- point specific alterations in carbon utilization. Results from our research will inform the development of future interventions, thus advancing the NIGMS mission to support biomedical research that increases our understanding of cellular processes and lays the foundation for advances in disease diagnosis, treatment, and prevention.
