2014:

Alexei Medvedev - Microbiology & Immunology - Initiation Mechanism of Norovirus Subgenomic RNA Synthesis

Norovirus (NV) is an enormous threat to public health. In the United States alone, NV is responsible for approximately 21 million cases of gastroenteritis on a yearly basis, is the most frequent cause of hospital-acquired infections, and is responsible for 65% of hospital unit closures, resulting in a devastating annual estimated loss of $5.7 billion. More alarmingly, though, after many years of research, details of the NV RNA replication cycle remain poorly understood and no replication schemes have been proposed in the literature. In view of that fact, and based on information detailed within a core sample of NV publications, the first-ever replication scheme for NV was proposed in the previous SRGP project. The replication mechanism was confirmed by filling in the gaps in our understanding of the steps that take place during the initiation of positive strand synthesis in NV and the role that viral protein VPg plays in that process. The current project is an extension of that work and attempts to apply findings of genomic RNA experiments to elucidating the mechanisms involved in initiation and synthesis of subgenomic RNA. The proposed investigations are all hypothesis-driven and based on principles firmly established in the literature, as well as findings uncovered during previous SRGP work. The experiments are designed to provide definitive answers to the tested concepts irrespective of the experimental outcomes. Furthermore, the studies are designed to advance the field by addressing specific absences of critical data in the literature.

Kyle Shattuck - IPN - Cholinergic Regulation of Attention: a Functional Magnetic Resonance Spectroscopy Study

The overall hypothesis of this proposal is that cortical cholinergic neurotransmission on both tonic and phasic timescales regulates the detection of salient cues during attentional performance in humans. These processes have been well elucidated in rodents using the sustained attention task with distractor loading (dSAT), which has recently been successfully adapted to human participants. Using our lab's ongoing development of functional magnetic resonance spectroscopy (fMRS), we aim to be the first to interrogate the neurobiological findings from this animal literature in human subjects.

Sweta Batni - Global Infectious Diseases - Using SPR to identify potential novel chemotherapeutics targeting methyltransferase in Giardia lamblia

Carrie Leonard - IPN - Analysis of endogenous EphA7 protein using a novel transgenic knock-in mouse

Proper development and function of the cerebral cortex depends upon the proper shape and connections of neurons. Alterations in neuronal shape and synapses are associate with a number of neurological disorders, including autism, mental retardation, and schizophrenia. Therefore, uncovering mechanisms that guide normal neuronal maturation is imperative to our understanding of etiology and pathology associated with these conditions. Here, the receptor EphA7 receptor has been identified as a novel regulator of cortical maturation. When EphA7 is absent in neurons, dendritic elaboration is affected early, while synapse formation and function are perturbed later. The EPHA7 gene results in two proteins due to alternative splicing: a full-length form (FLA7) and a truncated form (TRA7). Preliminary data suggests these splice variants govern the functional switch in EphA7 through development. mRNA analysis suggests temporal differences in expression between the isoforms, while exogenous protein expression suggests differences even within a neuron. However, there is currently no way to detect or isolate endogenous EphA7 protein for analysis. This proposal would create a new transgenic knock-in animal using the CRISPR/Cas9 genome editing system in collaboration with Washington University in St. Louis. The knock-in animal will express specific epitope-tagged EphA7 isoforms to allow immunohistochemical detection and isolation of endogenous protein. Expression patterns will be examined in the cortex, and potential binding partners will be determined using mass spectrometry. This proposal will create a new, much needed tool for the study of EphA7, contributing novel information to the field.

Heidi Coia - Biochemistry and Molecular BIology - A novel 3D model to study mechanisms in the progression of obesity related hepatocellular carcinoma

Liver cancer, the third most common cause of cancer-related mortality results in nearly 700,000 deaths per year worldwide [1]. Obesity is associated with 30% of these cases, specifically hepatocellular carcinoma (HCC). Mechanisms of obesity related (OR) HCC are not well characterized, but have been associated with the effects of chronic inflammation, disruption of regenerative liver properties, miRNA dysregulation, and more recently to the role of lipid peroxidation (LPO), generation of reactive oxygen species (ROS) and the resulting DNA damage [2,5]. OR HCC is a progressive disease initiated when triglycerides accumulate in hepatocytes, defined as non-alcoholic fatty liver disease (NAFLD). NAFLD can advance to non-alcoholic steatohepatitis (NASH) and cirrhosis; the risk of HCC increases at each progressive stage. In this study, a 3D cellular scaffold and microfluidic device that mimics liver physiology will be treated with fatty acids and other factors to promote NAFLD, NASH and HCC progression in vitro. Recently, organ-on-a-chip technology has provided a cost-effective way to study more physiologically relevant disease microenvironments compared to mouse models or cell culture alone [10,11]. Markers of disease progression will be monitored using western blot, RT-PCR and histology. DNA adducts, generated as a result of LPO will be elucidated by DNA extraction and mass spectroscopy. The results of this study will demonstrate the presence and role of adducts as a mechanism of DNA damage in OR HCC progression. Developing an innovative and specific model for OR HCC will be useful for future studies to help further define the mechanisms behind this deadly disease and investigate possible treatment options.