Dr. Haughey directs a disease-oriented research program that address questions in basic neurobiology, and clinical neurology. The primary research interests of the laboratory are: 1. To identify biomarkers markers for neurodegenerative diseases including HIV-Associated Neurocognitive Disorders, Multiple Sclerosis, and Alzheimer’s disease. In these studies, blood and cerebral spinal fluid samples obtained from ongoing clinical studies are analyzed for metabolic profiles through a variety of biochemical, mass spectrometry and bioinformatic techniques. These biomarkers can then be used in the diagnosis of disease, as prognostic indicators to predict disease trajectory, or as surrogate markers to track the effectiveness of disease modifying interventions. 2. To better understand how the lipid components of neuronal, and glial membranes interact with proteins to regulate signal transduction associated with differentiation, motility, inflammatory signaling, survival, and neuronal excitability. 3. To understand how extracellular vesicles (exosomes) released from brain resident cells regulate neuronal excitability, neural network activity, and peripheral immune responses to central nervous system damage and infections. 4. To develop small molecule therapeutics that regulate lipid metabolism as a neuroprotective and restorative strategy for neurodegenerative conditions.

The nervous system has extremely complex RNA processing regulation. Dysfunction of RNA metabolism has emerged to play crucial roles in multiple neurological diseases. Mutations and pathologies of several RNA-binding proteins are found to be associated with neurodegeneration in both amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). An alternative RNA-mediated toxicity arises from microsatellite repeat instability in the human genome. The expanded repeat-containing RNAs could potentially induce neuron toxicity by disrupting protein and RNA homeostasis through various mechanisms. The Sun Lab is interested in deciphering the RNA processing pathways altered by the ALS-causative mutants to uncover the mechanisms of toxicity and molecular basis of cell type-selective vulnerability. Another major focus of the group is to identify small molecule and genetic inhibitors of neuron toxic factors using various high-throughput screening platforms. Finally, we are also highly interested in developing novel CRISPR technique-based therapeutic strategies. We seek to translate the mechanistic findings at molecular level to therapeutic target development to advance treatment options against neurodegenerative diseases.

Our research is focused on understanding the basic mechanisms of programmed cell death in disease pathogenesis. Billions of cells die per day in the human body. Like cell division and differentiation, cell death is also critical for normal development and maintenance of healthy tissues. Apoptosis and other forms of cell death are required for trimming excess, expired and damaged cells. Therefore, many genetically programmed cell suicide pathways have evolved to promote long-term survival of species from yeast to humans. Defective cell death programs cause disease states. Insufficient cell death underlies human cancer and autoimmune disease, while excessive cell death underlies human neurological disorders and aging. Of particular interest to our group are the mechanisms by which Bcl-2 family proteins and other factors regulate programmed cell death, particularly in the nervous system, in cancer and in virus infections. Interestingly, cell death regulators also regulate many other cellular processes prior to a death stimulus, including neuronal activity, mitochondrial dynamics and energetics. We study these unknown mechanisms. We have reported that many insults can trigger cells to activate a cellular death pathway (Nature, 361:739-742, 1993), that several viruses encode proteins to block attempted cell suicide (Proc. Natl. Acad. Sci. 94: 690-694, 1997), that cellular anti-death genes can alter the pathogenesis of virus infections (Nature Med. 5:832-835, 1999) and of genetic diseases (PNAS. 97:13312-7, 2000) reflective of many human disorders. We have shown that anti-apoptotic Bcl-2 family proteins can be converted into killer molecules (Science 278:1966-8, 1997), that Bcl-2 family proteins interact with regulators of caspases and regulators of cell cycle check point activation (Molecular Cell 6:31-40, 2000). In addition, Bcl-2 family proteins have normal physiological roles in regulating mitochondrial fission/fusion and mitochondrial energetics to facilitate neuronal activity in healthy brains.