Sungjin Park, PhD

Research Interests

  • Neurosciences
  • Developmental Biology
  • Cell Signaling
  • Synapses
  • Neuron-Glia Interaction
  • Glycosylphosphatidylinositols
  • Membrane Proteins
  • Drug Discovery

Languages

  • English

Academic Information

  • Departments: Neurobiology & Anatomy - Assistant Professor

Academic Office Information

  • 801-581-6106
  • Biomedical Polymers Research Bldg
    Neurobiology & Anatomy
    20 S 2030 E, Room: 390 D
    Salt Lake City, UT 84112

Email: sungjin.park@neuro.utah.edu

Academic Bio

Cell-to-cell and cell-to-extracellular matrix (ECM) communication is critical for development and function of the nervous system. We study signaling pathways mediated by glycosylphosphatidylinositol (GPI)-anchored proteins (GPI-APs). GPI-APs play key roles in multiple processes including neurogenesis, axon guidance, synapse development and ECM formation. GPI-APs are a unique hybrid class of proteins that are both membrane bound, as well as cleaved and released from the membrane and thus play versatile roles in signal transduction on the cell surface and in the extracellular space. However, how GPI-dependent signaling pathways are regulated is poorly understood. By focusing on understudied pathways we hope to identify novel therapeutic targets for neurodevelopmental diseases caused by synaptogenic defects such as autism spectrum disorders and schizophrenia.

  1. Mechanisms of bi-directional neuron-astrocyte communication regulating synapse development and function

Astrocytes play important roles in multiple steps of synapse formation and function, many of which are mediated by released factors. However, the mechanism of release of these factors remains elusive. We have identified a novel pathway to release GPI-anchored synaptogenic factors from astrocytes via an astrocyte-specific GPI-anchor cleaving enzyme. We are investigating its regulatory mechanism and specific downstream effectors.

Is the release of synaptogenic factors constitutive or regulated by neuronal activity? We are working to identify specific signaling molecules secreted from neurons that facilitate the release of synaptogenic factors from astrocytes. Specifically, we are studying the regulated release of glypican-4, a GPI-anchored protein and how the GPI-anchor itself may play a role in this mechanism. We have generated a knock-in mouse line to study the contribution of the released vs membrane-bound forms of glypican-4 signaling both in vitro and in vivo.

  1. Molecular mechanisms mediating the formation of highly ordered ECM structures

How are complex ECM structures established outside the cell? What molecular mechanisms drive the assembly of the ECM? We focus on a specialized ECM structure in the inner ear, the tectorial membrane, which plays roles in amplification and propagation of sound waves. We found that GPI-anchorage of alpha-tectorin is required to prevent diffusion of ECM components and allow assembly of the tectorial membrane. We are currently investigating how its growth and characteristic ultrastructure are specified at the molecular level using newly generated knock-in mouse lines.

  1. Development and applications of a high-throughput live neuronal activity assay

Can we perform high-thought drug screen assay to identify drugs that modulate synapse development and function? Can we generate mutant neurons that bear a disease-causing mutation and simultaneously monitor altered neuronal activity only in the mutated neurons? We have developed a simple and robust assay to monitor the neuronal activity in live neurons by combining activity-dependent promoters and secreted reporters. We are optimizing this assay to establish large-scale analyses, drug screens and to combine it with cutting edge gene-editing techniques in order to study the effects of disease-causing mutations.

Education History

Type School Degree
Postdoctoral Fellowship Johns Hopkins University School of Medicine
Neuroscience
Postdoctoral Fellow
Doctoral Training Johns Hopkins University School of Medicine
Neuroscience
Ph.D.
Graduate Training Seoul National University
Molecular Biology
M.S.
Undergraduate Seoul National University
Molecular Biology
B.S.

Global Impact

Education History

Type School Degree Country
Graduate Training Seoul National University
Molecular Biology
M.S. Korea
Undergraduate Seoul National University
Molecular Biology
B.S. Korea

Selected Publications

Journal Article

  1. Dobrowolski M, Cave C, Levy-Myers R, Lee C, Park S, Choi BR, Xiao B, Yang W, Sockanathan S (2020). GDE3 regulates oligodendrocyte precursor proliferation via release of soluble CNTFR╬▒. Development, 147(2).
  2. Kim DK, Kim JA, Park J, Niazi A, Almishaal A, Park S (2019). The release of surface-anchored ╬▒-tectorin, an apical extracellular matrix protein, mediates tectorial membrane organization. Sci Adv, 5(11), eaay6300.
  3. Kim BJ, Kim DK, Han JH, Oh J, Kim AR, Lee C, Kim NK, Park HR, Kim MY, Lee S, Lee S, Oh DY, Park WY, Park S, Choi BY (2019). Clarification of glycosylphosphatidylinositol anchorage of OTOANCORIN and human OTOA variants associated with deafness. Hum Mutat, 40(5), 525-531.
  4. Cave C, Park S, Rodriguez M, Nakamura M, Hoke A, Pletnikov M, Sockanathan S (2017). GDE2 is essential for neuronal survival in the postnatal mammalian spinal cord. Mol Neurodegener, 12(1), 8.
  5. Na Y, Park S, Lee C, Kim DK, Park JM, Sockanathan S, Huganir RL, Worley PF (2016). Real-Time Imaging Reveals Properties of Glutamate-Induced Arc/Arg 3.1 Translation in Neuronal Dendrites.LID - S0896-6273(16)30294-X [pii]LID - 10.1016/j.neuron.2016.06.017 [doi]. (Epub ahead of print) Neuron.
  6. Choi J, Park S, Sockanathan S (2014). Activated retinoid receptors are required for the migration and fate maintenance of subsets of cortical neurons. Development, 141(5), 1151-60.
  7. Kim YS, Kang E, Makino Y, Park S, Shin JH, Song H, Launay P, Linden DJ (2013). Characterizing the conductance underlying depolarization-induced slow current in cerebellar Purkinje cells. J Neurophysiol, 109(4), 1174-81.
  8. Park S, Lee C, Sabharwal P, Zhang M, Meyers CL, Sockanathan S (2013). GDE2 promotes neurogenesis by glycosylphosphatidylinositol-anchor cleavage of RECK. Science, 339(6117), 324-8.
  9. Rodriguez M, Choi J, Park S, Sockanathan S (2012). Gde2 regulates cortical neuronal identity by controlling the timing of cortical progenitor differentiation. Development, 139(20), 3870-9.
  10. Sabharwal P, Lee C, Park S, Rao M, Sockanathan S (2011). GDE2 regulates subtype-specific motor neuron generation through inhibition of Notch signaling. Neuron, 71(6), 1058-70.
  11. Hu JH, Park JM, Park S, Xiao B, Dehoff MH, Kim S, Hayashi T, Schwarz MK, Huganir RL, Seeburg PH, Linden DJ, Worley PF (2010). Homeostatic scaling requires group I mGluR activation mediated by Homer1a. Neuron, 68(6), 1128-42.
  12. Butkinaree C, Cheung WD, Park S, Park K, Barber M, Hart GW (2008). Characterization of beta-N-acetylglucosaminidase cleavage by caspase-3 during apoptosis. J Biol Chem, 283(35), 23557-66.
  13. Park S, Park JM, Kim S, Kim JA, Shepherd JD, Smith-Hicks CL, Chowdhury S, Kaufmann W, Kuhl D, Ryazanov AG, Huganir RL, Linden DJ, Worley PF (2008). Elongation factor 2 and fragile X mental retardation protein control the dynamic translation of Arc/Arg3.1 essential for mGluR-LTD. Neuron, 59(1), 70-83.