Honors & Awards


  • Medical Faculty Association’s Best Research Award, Third Place Winner, University of Miami (2019)
  • Stanford CVI Travel Award, Stanford Cardiovascular Institute (10/2019)
  • Wood-Whelan Research Fellowships, International Union of Biochemistry and Molecular Biology (IUBMB) (02/2017)
  • Predoctoral Fellowships, American Heart Association (AHA) (01/2016-12/2017)
  • Fellowships, Sangmyung University (03/1997-08/1997)

Professional Education


  • Doctor of Philosophy, University of Miami (2018)
  • Master of Arts, University of Kentucky (2011)
  • Master of Arts, SangMyung University (2002)
  • Bachelor of Arts, SangMyung University (2000)

Stanford Advisors


All Publications


  • ZEB2 Shapes the Epigenetic Landscape of Atherosclerosis Circulation Cheng, P., Wirka, R. C., Clarke, L., Zhao, Q., Kundu, R., Nguyen, T., Nair, S., Sharma, D., Kim, H., Shi, H., Assimes, T., Kim, J., Kundaje, A., Quertermous, T. 2022; 145 (6): 469–485

    Abstract

    Background: Smooth muscle cells (SMC) transition into a number of different phenotypes during atherosclerosis, including those that resemble fibroblasts and chondrocytes, and make up the majority of cells in the atherosclerotic plaque. To better understand the epigenetic and transcriptional mechanisms that mediate these cell state changes, and how they relate to risk for coronary artery disease (CAD), we have investigated the causality and function of transcription factors (TFs) at genome wide associated loci. Methods: We employed CRISPR-Cas 9 genome and epigenome editing to identify the causal gene and cell(s) for a complex CAD GWAS signal at 2q22.3. Subsequently, single-cell epigenetic and transcriptomic profiling in murine models and human coronary artery smooth muscle cells were employed to understand the cellular and molecular mechanism by which this CAD risk gene exerts its function. Results: CRISPR-Cas 9 genome and epigenome editing showed that the complex CAD genetic signals within a genomic region at 2q22.3 lie within smooth muscle long-distance enhancers for ZEB2, a TF extensively studied in the context of epithelial mesenchymal transition (EMT) in development and cancer. ZEB2 regulates SMC phenotypic transition through chromatin remodeling that obviates accessibility and disrupts both Notch and TGFβ signaling, thus altering the epigenetic trajectory of SMC transitions. SMC specific loss of ZEB2 resulted in an inability of transitioning SMCs to turn off contractile programing and take on a fibroblast-like phenotype, but accelerated the formation of chondromyocytes, mirroring features of high-risk atherosclerotic plaques in human coronary arteries. Conclusions: These studies identify ZEB2 as a new CAD GWAS gene that affects features of plaque vulnerability through direct effects on the epigenome, providing a new thereapeutic approach to target vascular disease.

    View details for DOI 10.1161/CIRCULATIONAHA.121.057789

  • Mitochondrial MTG1 is necessary for proper human cardiomyocyte activity and zebrafish cardiac development. Comment to "Novel role of mitochondrial GTPases 1 in pathological cardiac hypertrophy" JOURNAL OF MOLECULAR AND CELLULAR CARDIOLOGY Kim, H., Barrientos, A. 2019; 129: 1

    View details for DOI 10.1016/j.yjmcc.2019.02.005

    View details for Web of Science ID 000466833500001

    View details for PubMedID 30763588

  • Human GTPBP10 is required for mitoribosome maturation NUCLEIC ACIDS RESEARCH Maiti, P., Kim, H., Tu, Y., Barrientos, A. 2018; 46 (21): 11423–37

    Abstract

    Most steps on the biogenesis of the mitochondrial ribosome (mitoribosome) occur near the mitochondrial DNA nucleoid, in RNA granules, which contain dedicated RNA metabolism and mitoribosome assembly factors. Here, analysis of the RNA granule proteome identified the presence of a set of small GTPases that belong to conserved families of ribosome assembly factors. We show that GTPBP10, a member of the conserved Obg family of P-loop small G proteins, is a mitochondrial protein and have used gene-editing technologies to create a HEK293T cell line KO for GTPBP10. The absence of GTPBP10 leads to attenuated mtLSU and mtSSU levels and the virtual absence of the 55S monosome, which entirely prevents mitochondrial protein synthesis. We show that a fraction of GTPBP10 cosediments with the large mitoribosome subunit and the monosome. GTPBP10 physically interacts with the 16S rRNA, but not with the 12S rRNA, and crosslinks with several mtLSU proteins. Additionally, GTPBP10 is indirectly required for efficient processing of the 12S-16S rRNA precursor transcript, which could explain the mtSSU accumulation defect. We propose that GTPBP10 primarily ensures proper mtLSU maturation and ultimately serves to coordinate mtSSU and mtLSU accumulation then providing a quality control check-point function during mtLSU assembly that minimizes premature subunit joining.

    View details for DOI 10.1093/nar/gky938

    View details for Web of Science ID 000456710000029

    View details for PubMedID 30321378

    View details for PubMedCentralID PMC6265488

  • MTG1 couples mitoribosome large subunit assembly with intersubunit bridge formation NUCLEIC ACIDS RESEARCH Kim, H., Barrientos, A. 2018; 46 (16): 8435–53

    Abstract

    Mammalian mitochondrial ribosomes (mitoribosomes) synthesize 13 proteins, essential components of the oxidative phosphorylation system. They are linked to mitochondrial disorders, often involving cardiomyopathy. Mitoribosome biogenesis is assisted by multiple cofactors whose specific functions remain largely uncharacterized. Here, we examined the role of human MTG1, a conserved ribosome assembly guanosine triphosphatase. MTG1-silencing in human cardiomyocytes and developing zebrafish revealed early cardiovascular lesions. A combination of gene-editing and biochemical approaches using HEK293T cells demonstrated that MTG1 binds to the large subunit (mtLSU) 16S ribosomal RNA to facilitate incorporation of late-assembly proteins. Furthermore, MTG1 interacts with mtLSU uL19 protein and mtSSU mS27, a putative guanosine triphosphate-exchange factor (GEF), to enable MTG1 release and the formation of the mB6 intersubunit bridge. In this way, MTG1 establishes a quality control checkpoint in mitoribosome assembly. In conclusion, MTG1 controls mitochondrial translation by coupling mtLSU assembly with intersubunit bridge formation using the intrinsic GEF activity acquired by the mtSSU through mS27, a unique occurrence in translational systems.

    View details for DOI 10.1093/nar/gky672

    View details for Web of Science ID 000450950500035

    View details for PubMedID 30085276

    View details for PubMedCentralID PMC6144824

  • Mitochondrial ribosomes in cancer SEMINARS IN CANCER BIOLOGY Kim, H., Maiti, P., Barrientos, A. 2017; 47: 67–81

    Abstract

    Mitochondria play fundamental roles in the regulation of life and death of eukaryotic cells. They mediate aerobic energy conversion through the oxidative phosphorylation (OXPHOS) system, and harbor and control the intrinsic pathway of apoptosis. As a descendant of a bacterial endosymbiont, mitochondria retain a vestige of their original genome (mtDNA), and its corresponding full gene expression machinery. Proteins encoded in the mtDNA, all components of the multimeric OXPHOS enzymes, are synthesized in specialized mitochondrial ribosomes (mitoribosomes). Mitoribosomes are therefore essential in the regulation of cellular respiration. Additionally, an increasing body of literature has been reporting an alternative role for several mitochondrial ribosomal proteins as apoptosis-inducing factors. No surprisingly, the expression of genes encoding for mitoribosomal proteins, mitoribosome assembly factors and mitochondrial translation factors is modified in numerous cancers, a trait that has been linked to tumorigenesis and metastasis. In this article, we will review the current knowledge regarding the dual function of mitoribosome components in protein synthesis and apoptosis and their association with cancer susceptibility and development. We will also highlight recent developments in targeting mitochondrial ribosomes for the treatment of cancer.

    View details for DOI 10.1016/j.semcancer.2017.04.004

    View details for Web of Science ID 000418223400008

    View details for PubMedID 28445780

    View details for PubMedCentralID PMC5662495

  • Methamphetamine-induced Occludin Endocytosis Is Mediated by the Arp2/3 Complex-regulated Actin Rearrangement JOURNAL OF BIOLOGICAL CHEMISTRY Park, M., Kim, H., Lim, B., Wylegala, A., Toborek, M. 2013; 288 (46): 33324–34

    Abstract

    Methamphetamine (METH) is a drug of abuse with neurotoxic and neuroinflammatory effects, which include disruption of the blood-brain barrier (BBB) and alterations of tight junction protein expression. This study focused on the actin cytoskeletal rearrangement as a modulator of METH-induced redistribution of tight junction protein occludin in brain endothelial cells. Exposure to METH resulted in a shift of occludin localization from plasma membranes to endosomes. These changes were accompanied by activation of the actin-related protein 2/3 (Arp2/3) complex, which stimulates actin polymerization by promoting actin nucleation. In addition, METH-induced coronin-1b phosphorylation diminishes the inhibitory effect of nonphosphorylated coronin-1b on actin nucleation. Blocking actin nucleation with CK-666, a specific inhibitor of the Arp2/3 complex, protected against METH-induced occludin internalization and increased transendothelial monocyte migration. Importantly, treatment with CK-666 attenuated a decrease in occludin levels in brain microvessels and BBB permeability of METH-injected mice. These findings indicate that actin cytoskeletal dynamics is detrimental to METH-induced BBB dysfunction by increasing internalization of occludin.

    View details for DOI 10.1074/jbc.M113.483487

    View details for Web of Science ID 000328841700047

    View details for PubMedID 24081143

    View details for PubMedCentralID PMC3829179

  • Cancer Prevention with Promising Natural Products: Mechanisms of Action and Molecular Targets ANTI-CANCER AGENTS IN MEDICINAL CHEMISTRY Pratheeshkumar, P., Sreekala, C., Zhang, Z., Budhraja, A., Ding, S., Son, Y., Wang, X., Hitron, A., Hyun-Jung, K., Wang, L., Lee, J., Shi, X. 2012; 12 (10): 1159–84

    Abstract

    Cancer is the second leading cause of death worldwide. There is greater need for more effective and less toxic therapeutic and preventive strategies. Natural products are becoming an important research area for novel and bioactive molecules for drug discovery. Phytochemicals and dietary compounds have been used for the treatment of cancer throughout history due to their safety, low toxicity, and general availability. Many active phytochemicals are in human clinical trials. Studies have indicated that daily consumption of dietary phytochemicals have cancer protective effects against carcinogens. They can inhibit, delay, or reverse carcinogenesis by inducing detoxifying and antioxidant enzymes systems, regulating inflammatory and proliferative signaling pathways, and inducing cell cycle arrest and apoptosis. Epidemiological studies have also revealed that high dietary intakes of fruits and vegetables reduce the risk of cancer. This review discusses potential natural cancer preventive compounds, their molecular targets, and their mechanisms of actions.

    View details for DOI 10.2174/187152012803833035

    View details for Web of Science ID 000311073800002

    View details for PubMedID 22583402

    View details for PubMedCentralID PMC4983770

  • Nucleotide divergence analysis of IGS region in Fusarium oxysporum and its formae speciales based on the sequence Mycobiology Kim, H., Min, B. 2004; 32 (3): 119-122
  • Variation of the Intergenetic Spacer (IGS) Region of Ribosomal DNA among Fusarium oxysporum formae species The Journal of Microbiology Kim, H., Choi, Y., Min, B. 2001; 39 (4): 265-272