Academic Appointments

Honors & Awards

  • Scholarship Award, Santa Cruz Developmental Biology Meeting, Santa Cruz, CA (2018)
  • Best Talk Award, 2nd Annual CVI Postdoctoral Conference, Stanford, CA (2017)
  • Outstanding Student Award, New England Bioscience Society, Boston, MA (2015)
  • Poster Award, 2nd place, Activated Egg Symposium, Boston, MA (2013)
  • Travel Grant Award, Annual Meeting of Society of Developmental Biology, Montreal, Canada (2012)
  • Poster award, 1st place, Northeast Regional Meeting of the Society for Developmental Biology, Woods Hole, MA (2010)
  • Poster award, 1st place, Annual Meeting of Animal Science Society in Korea (2004)
  • Travel Grant Award, Visiting Japan as a student representative for Korea University (2002)
  • Academic scholarship award, PURINA Korea (2001)

Professional Education

  • Ph.D, University of Massachusetts, Amherst, Developmental Biology (2015)
  • MS, University of Massachusetts, Amherst, Food Science (2009)
  • MS, Korea University, Animal Nutritioin (2004)
  • BS, Korea University, Animal Science (2002)

All Publications

  • In Vivo Stem Cell Imaging Principles and Applications. International journal of stem cells Hong, S., Lee, D. S., Bae, G. W., Jeon, J., Kim, H. K., Rhee, S., Jung, K. O. 2023


    Stem cells are the foundational cells for every organ and tissue in our body. Cell-based therapeutics using stem cells in regenerative medicine have received attracting attention as a possible treatment for various diseases caused by congenital defects. Stem cells such as induced pluripotent stem cells (iPSCs) as well as embryonic stem cells (ESCs), mesenchymal stem cells (MSCs), and neuroprogenitors stem cells (NSCs) have recently been studied in various ways as a cell-based therapeutic agent. When various stem cells are transplanted into a living body, they can differentiate and perform complex functions. For stem cell transplantation, it is essential to determine the suitability of the stem cell-based treatment by evaluating the origin of stem, the route of administration, in vivo bio-distribution, transplanted cell survival, function, and mobility. Currently, these various stem cells are being imaged in vivo through various molecular imaging methods. Various imaging modalities such as optical imaging, magnetic resonance imaging (MRI), ultrasound (US), positron emission tomography (PET), and single-photon emission computed tomography (SPECT) have been introduced for the application of various stem cell imaging. In this review, we discuss the principles and recent advances of in vivo molecular imaging for application of stem cell research.

    View details for DOI 10.15283/ijsc23045

    View details for PubMedID 37643761

  • Neighbor-specific gene expression revealed from physically interacting cells during mouse embryonic development. Proceedings of the National Academy of Sciences of the United States of America Kim, J., Rothova, M. M., Madan, E., Rhee, S., Weng, G., Palma, A. M., Liao, L., David, E., Amit, I., Hajkarim, M. C., Vudatha, V., Gutierrez-Garcia, A., Moreno, E., Winn, R., Trevino, J., Fisher, P. B., Brickman, J. M., Gogna, R., Won, K. J. 2023; 120 (2): e2205371120


    Development of multicellular organisms is orchestrated by persistent cell-cell communication between neighboring partners. Direct interaction between different cell types can induce molecular signals that dictate lineage specification and cell fate decisions. Current single-cell RNA-seq technology cannot adequately analyze cell-cell contact-dependent gene expression, mainly due to the loss of spatial information. To overcome this obstacle and resolve cell-cell contact-specific gene expression during embryogenesis, we performed RNA sequencing of physically interacting cells (PIC-seq) and assessed them alongside similar single-cell transcriptomes derived from developing mouse embryos between embryonic day (E) 7.5 and E9.5. Analysis of the PIC-seq data identified gene expression signatures that were dependent on the presence of specific neighboring cell types. Our computational predictions, validated experimentally, demonstrated that neural progenitor (NP) cells upregulate Lhx5 and Nkx2-1 genes, when exclusively interacting with definitive endoderm (DE) cells. Moreover, there was a reciprocal impact on the transcriptome of DE cells, as they tend to upregulate Rax and Gsc when in contact with NP cells. Using individual cell transcriptome data, we formulated a means of computationally predicting the impact of one cell type on the transcriptome of its neighboring cell types. We have further developed a distinctive spatial-t-distributed stochastic neighboring embedding to display the pseudospatial distribution of cells in a 2-dimensional space. In summary, we describe an innovative approach to study contact-specific gene regulation during embryogenesis.

    View details for DOI 10.1073/pnas.2205371120

    View details for PubMedID 36595695

  • Statins improve endothelial function via suppression of epigenetic-driven EndMT Nature Cardiovascular Research Liu, C., Shen, M., Tan, W. L., Chen, I. Y., Liu, Y., Yu, X., Zhang, A., Liu, Y., Zhao, M., Ameen, M., Zhang, M., Gross, E. R., Lei, Q. S., Sayed, N., Wu, J. C. 2023
  • An NKX-COUP-TFII morphogenetic code directs mucosal endothelial addressin expression. Nature communications Dinh, T. T., Xiang, M., Rajaraman, A., Wang, Y., Salazar, N., Zhu, Y., Roper, W., Rhee, S., Brulois, K., O'Hara, E., Kiefel, H., Dinh, T. M., Bi, Y., Gonzalez, D., Bao, E. P., Red-Horse, K., Balogh, P., Gabris, F., Gaszner, B., Berta, G., Pan, J., Butcher, E. C. 2022; 13 (1): 7448


    Immunoglobulin family and carbohydrate vascular addressins encoded by Madcam1 and St6gal1 control lymphocyte homing into intestinal tissues, regulating immunity and inflammation. The addressins are developmentally programmed to decorate endothelial cells lining gut post-capillary and high endothelial venules (HEV), providing a prototypical example of organ- and segment-specific endothelial specialization. We identify conserved NKX-COUP-TFII composite elements (NCCE) in regulatory regions of Madcam1 and St6gal1 that bind intestinal homeodomain protein NKX2-3 cooperatively with venous nuclear receptor COUP-TFII to activate transcription. The Madcam1 element also integrates repressive signals from arterial/capillary Notch effectors. Pan-endothelial COUP-TFII overexpression induces ectopic addressin expression in NKX2-3+ capillaries, while NKX2-3 deficiency abrogates expression by HEV. Phylogenetically conserved NCCE are enriched in genes involved in neuron migration and morphogenesis of the heart, kidney, pancreas and other organs. Our results define an NKX-COUP-TFII morphogenetic code that targets expression of mucosal vascular addressins.

    View details for DOI 10.1038/s41467-022-34991-2

    View details for PubMedID 36460642

  • Untold story of human cervical cancers: HPV-negative cervical cancer BMB REPORTS Lee, J., Chung, Y., Rhee, S., Kim, T. 2022; 55 (9): 429-438
  • In vivo molecular and single cell imaging BMB REPORTS Hong, S., Rhee, S., Jung, K. 2022; 55 (6): 267-274
  • Cannabinoid receptor 1 antagonist genistein attenuates marijuana-induced vascular inflammation. Cell Wei, T. T., Chandy, M., Nishiga, M., Zhang, A., Kumar, K. K., Thomas, D., Manhas, A., Rhee, S., Justesen, J. M., Chen, I. Y., Wo, H. T., Khanamiri, S., Yang, J. Y., Seidl, F. J., Burns, N. Z., Liu, C., Sayed, N., Shie, J. J., Yeh, C. F., Yang, K. C., Lau, E., Lynch, K. L., Rivas, M., Kobilka, B. K., Wu, J. C. 2022


    Epidemiological studies reveal that marijuana increases the risk of cardiovascular disease (CVD); however, little is known about the mechanism. Δ9-tetrahydrocannabinol (Δ9-THC), the psychoactive component of marijuana, binds to cannabinoid receptor 1 (CB1/CNR1) in the vasculature and is implicated in CVD. A UK Biobank analysis found that cannabis was an risk factor for CVD. We found that marijuana smoking activated inflammatory cytokines implicated in CVD. In silico virtual screening identified genistein, a soybean isoflavone, as a putative CB1 antagonist. Human-induced pluripotent stem cell-derived endothelial cells were used to model Δ9-THC-induced inflammation and oxidative stress via NF-κB signaling. Knockdown of the CB1 receptor with siRNA, CRISPR interference, and genistein attenuated the effects of Δ9-THC. In mice, genistein blocked Δ9-THC-induced endothelial dysfunction in wire myograph, reduced atherosclerotic plaque, and had minimal penetration of the central nervous system. Genistein is a CB1 antagonist that attenuates Δ9-THC-induced atherosclerosis.

    View details for DOI 10.1016/j.cell.2022.04.005

    View details for PubMedID 35489334

  • Vein to artery: the first arteriogenesis in the mammalian embryo. Cell research Rhee, S., Wu, J. C. 2022

    View details for DOI 10.1038/s41422-022-00629-7

    View details for PubMedID 35165423

  • Endocardial/endothelial angiocrines regulate cardiomyocyte development and maturation and induce features of ventricular non-compaction. European heart journal Rhee, S., Paik, D. T., Yang, J. Y., Nagelberg, D., Williams, I., Tian, L., Roth, R., Chandy, M., Ban, J., Belbachir, N., Kim, S., Zhang, H., Phansalkar, R., Wong, K. M., King, D. A., Valdez, C., Winn, V. D., Morrison, A. J., Wu, J. C., Red-Horse, K. 2021


    AIMS: Non-compaction cardiomyopathy is a devastating genetic disease caused by insufficient consolidation of ventricular wall muscle that can result in inadequate cardiac performance. Despite being the third most common cardiomyopathy, the mechanisms underlying the disease, including the cell types involved, are poorly understood. We have previously shown that endothelial cell-specific deletion of the chromatin remodeller gene Ino80 results in defective coronary vessel development that leads to ventricular non-compaction in embryonic mouse hearts. We aimed to identify candidate angiocrines expressed by endocardial and ECs inwildtype and LVNC conditions in Tie2Cre;Ino80fl/fl transgenic embryonic mouse hearts, and test the effect of these candidates on cardiomyocyte proliferation and maturation.METHODS AND RESULTS: We used single-cell RNA-sequencing to characterize endothelial and endocardial defects in Ino80-deficient hearts. We observed a pathological endocardial cell population in the non-compacted hearts and identified multiple dysregulated angiocrine factors that dramatically affected cardiomyocyte behaviour. We identified Col15A1 as a coronary vessel-secreted angiocrine factor, downregulated by Ino80-deficiency, that functioned to promote cardiomyocyte proliferation. Furthermore, mutant endocardial and endothelial cells (ECs) up-regulated expression of secreted factors, such as Tgfbi, Igfbp3, Isg15, and Adm, which decreased cardiomyocyte proliferation and increased maturation.CONCLUSIONS: These findings support a model where coronary ECs normally promote myocardial compaction through secreted factors, but that endocardial and ECs can secrete factors that contribute to non-compaction under pathological conditions.

    View details for DOI 10.1093/eurheartj/ehab298

    View details for PubMedID 34279605

  • miR-106a-363 cluster in extracellular vesicles promotes endogenous myocardial repair via Notch3 pathway in ischemic heart injury. Basic research in cardiology Jung, J. H., Ikeda, G. n., Tada, Y. n., von Bornstädt, D. n., Santoso, M. R., Wahlquist, C. n., Rhee, S. n., Jeon, Y. J., Yu, A. C., O'brien, C. G., Red-Horse, K. n., Appel, E. A., Mercola, M. n., Woo, J. n., Yang, P. C. 2021; 116 (1): 19


    Endogenous capability of the post-mitotic human heart holds great promise to restore the injured myocardium. Recent evidence indicates that the extracellular vesicles (EVs) regulate cardiac homeostasis and regeneration. Here, we investigated the molecular mechanism of EVs for self-repair. We isolated EVs from human iPSC-derived cardiomyocytes (iCMs), which were exposed to hypoxic (hEVs) and normoxic conditions (nEVs), and examined their roles in in vitro and in vivo models of cardiac injury. hEV treatment significantly improved the viability of hypoxic iCMs in vitro and cardiac function of severely injured murine myocardium in vivo. Microarray analysis of the EVs revealed significantly enriched expression of the miR-106a-363 cluster (miR cluster) in hEVs vs. nEVs. This miR cluster preserved survival and contractility of hypoxia-injured iCMs and maintained murine left-ventricular (LV) chamber size, improved LV ejection fraction, and reduced myocardial fibrosis of the injured myocardium. RNA-Seq analysis identified Jag1-Notch3-Hes1 as a target intracellular pathway of the miR cluster. Moreover, the study found that the cell cycle activator and cytokinesis genes were significantly up-regulated in the iCMs treated with miR cluster and Notch3 siRNA. Together, these results suggested that the miR cluster in the EVs stimulated cardiomyocyte cell cycle re-entry by repressing Notch3 to induce cell proliferation and augment myocardial self-repair. The miR cluster may represent an effective therapeutic approach for ischemic cardiomyopathy.

    View details for DOI 10.1007/s00395-021-00858-8

    View details for PubMedID 33742276

  • Identification of Lymphatic and Hematogenous Routes of Rapidly Labeled Radioactive and Fluorescent Exosomes through Highly Sensitive Multimodal Imaging. International journal of molecular sciences Jung, K. O., Kim, Y., Chung, S., Lee, C., Rhee, S., Pratx, G., Chung, J., Youn, H. 2020; 21 (21)


    There has been considerable interest in the clinical use of exosomes as delivery vehicles for treatments as well as for promising diagnostic biomarkers, but the physiological distribution of exosomes must be further elucidated to validate their efficacy and safety. Here, we aimed to develop novel methods to monitor exosome biodistribution in vivo using positron emission tomography (PET) and optical imaging. Exosomes were isolated from cultured mouse breast cancer cells and labeled for PET and optical imaging. In mice, radiolabeled and fluorescently labeled exosomes were injected both via lymphatic and hematogenous metastatic routes. PET and fluorescence images were obtained and quantified. Radioactivity and fluorescence intensity of ex vivo organs were measured. PET signals from exosomes in the lymphatic metastatic route were observed in the draining sentinel lymph nodes. Immunohistochemistry revealed greater exosome uptake in brachial and axillary versus inguinal lymph nodes. Following administration through the hematogenous metastasis pathway, accumulation of exosomes was clearly observed in the lungs, liver, and spleen. Exosomes from tumor cells were successfully labeled with 64Cu (or 68Ga) and fluorescence and were visualized via PET and optical imaging, suggesting that this simultaneous and rapid labeling method could provide valuable information for further exosome translational research and clinical applications.

    View details for DOI 10.3390/ijms21217850

    View details for PubMedID 33105908

  • Single-Cell RNA-seq Unveils Unique Transcriptomic Signatures of Organ-Specific Endothelial Cells. Circulation Paik, D. T., Tian, L., Williams, I. M., Rhee, S., Zhang, H., Liu, C., Mishra, R., Wu, S. M., Red-Horse, K., Wu, J. C. 2020


    Background: Endothelial cells (ECs) display considerable functional heterogeneity depending on the vessel and tissue in which they are located. While these functional differences are presumably imprinted in the transcriptome, the pathways and networks which sustain EC heterogeneity have not been fully delineated. Methods: To investigate the transcriptomic basis of EC specificity, we analyzed single-cell RNA-sequencing (scRNA-seq) data from tissue-specific mouse ECs generated by the Tabula Muris consortium. We employed a number of bioinformatics tools to uncover markers and sources of EC heterogeneity from scRNA-seq data. Results: We found a strong correlation between tissue-specific EC transcriptomic measurements generated by either scRNA-seq or bulk RNA-seq, thus validating the approach. Using a graph-based clustering algorithm, we found that certain tissue-specific ECs cluster strongly by tissue (e.g. liver, brain) whereas others (i.e. adipose, heart) have considerable transcriptomic overlap with ECs from other tissues. We identified novel markers of tissue-specific ECs and signaling pathways that may be involved in maintaining their identity. Sex was a considerable source of heterogeneity in the endothelial transcriptome and we discovered Lars2 to be a gene that is highly enriched in ECs from male mice. In addition, we found that markers of heart and lung ECs in mice were conserved in human fetal heart and lung ECs. Finally, we identified potential angiocrine interactions between tissue-specific ECs and other cell types by analyzing ligand and receptor expression patterns. Conclusions: In summary, we use scRNA-seq data generated by the Tabula Muris consortium to uncover transcriptional networks that maintain tissue-specific EC identity and to identify novel angiocrine and functional relationships between tissue-specific ECs.

    View details for DOI 10.1161/CIRCULATIONAHA.119.041433

    View details for PubMedID 32929989

  • Single-cell and spatial transcriptomics approaches of cardiovascular development and disease BMB REPORTS Roth, R., Kim, S., Kim, J., Rhee, S. 2020; 53 (8): 393–99
  • Wnt Activation and Reduced Cell-Cell Contact Synergistically Induce Massive Expansion of Functional Human iPSC-Derived Cardiomyocytes. Cell stem cell Buikema, J. W., Lee, S. n., Goodyer, W. R., Maas, R. G., Chirikian, O. n., Li, G. n., Miao, Y. n., Paige, S. L., Lee, D. n., Wu, H. n., Paik, D. T., Rhee, S. n., Tian, L. n., Galdos, F. X., Puluca, N. n., Beyersdorf, B. n., Hu, J. n., Beck, A. n., Venkamatran, S. n., Swami, S. n., Wijnker, P. n., Schuldt, M. n., Dorsch, L. M., van Mil, A. n., Red-Horse, K. n., Wu, J. Y., Geisen, C. n., Hesse, M. n., Serpooshan, V. n., Jovinge, S. n., Fleischmann, B. K., Doevendans, P. A., van der Velden, J. n., Garcia, K. C., Wu, J. C., Sluijter, J. P., Wu, S. M. 2020; 27 (1): 50–63.e5


    Modulating signaling pathways including Wnt and Hippo can induce cardiomyocyte proliferation in vivo. Applying these signaling modulators to human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) in vitro can expand CMs modestly (<5-fold). Here, we demonstrate massive expansion of hiPSC-CMs in vitro (i.e., 100- to 250-fold) by glycogen synthase kinase-3β (GSK-3β) inhibition using CHIR99021 and concurrent removal of cell-cell contact. We show that GSK-3β inhibition suppresses CM maturation, while contact removal prevents CMs from cell cycle exit. Remarkably, contact removal enabled 10 to 25 times greater expansion beyond GSK-3β inhibition alone. Mechanistically, persistent CM proliferation required both LEF/TCF activity and AKT phosphorylation but was independent from yes-associated protein (YAP) signaling. Engineered heart tissues from expanded hiPSC-CMs showed comparable contractility to those from unexpanded hiPSC-CMs, demonstrating uncompromised cellular functionality after expansion. In summary, we uncovered a molecular interplay that enables massive hiPSC-CM expansion for large-scale drug screening and tissue engineering applications.

    View details for DOI 10.1016/j.stem.2020.06.001

    View details for PubMedID 32619518

  • Whole-body tracking of single cells via positron emission tomography. Nature biomedical engineering Jung, K. O., Kim, T. J., Yu, J. H., Rhee, S. n., Zhao, W. n., Ha, B. n., Red-Horse, K. n., Gambhir, S. S., Pratx, G. n. 2020


    In vivo molecular imaging can measure the average kinetics and movement routes of injected cells through the body. However, owing to non-specific accumulation of the contrast agent and its efflux from the cells, most of these imaging methods inaccurately estimate the distribution of the cells. Here, we show that single human breast cancer cells loaded with mesoporous silica nanoparticles concentrating the 68Ga radioisotope and injected into immunodeficient mice can be tracked in real time from the pattern of annihilation photons detected using positron emission tomography, with respect to anatomical landmarks derived from X-ray computed tomography. The cells travelled at an average velocity of 50 mm s-1 and arrested in the lungs 2-3 s after tail-vein injection into the mice, which is consistent with the blood-flow rate. Single-cell tracking could be used to determine the kinetics of cell trafficking and arrest during the earliest phase of the metastatic cascade, the trafficking of immune cells during cancer immunotherapy and the distribution of cells after transplantation.

    View details for DOI 10.1038/s41551-020-0570-5

    View details for PubMedID 32541917

  • KEAP1/NFE2L2 mutations predict lung cancer radiation resistance that can be targeted by glutaminase inhibition. Cancer discovery Binkley, M. S., Jeon, Y. J., Nesselbush, M. n., Moding, E. J., Nabet, B. Y., Almanza, D. n., Kunder, C. n., Stehr, H. n., Yoo, C. H., Rhee, S. n., Xiang, M. n., Chabon, J. J., Hamilton, E. n., Kurtz, D. M., Gojenola, L. n., Owen, S. G., Ko, R. B., Shin, J. H., Maxim, P. G., Lui, N. S., Backhus, L. M., Berry, M. F., Shrager, J. B., Ramchandran, K. J., Padda, S. K., Das, M. n., Neal, J. W., Wakelee, H. A., Alizadeh, A. A., Loo, B. W., Diehn, M. n. 2020


    Tumor genotyping is not routinely performed in localized non-small cell lung cancer (NSCLC) due to lack of associations of mutations with outcome. Here, we analyze 232 consecutive patients with localized NSCLC and demonstrate that KEAP1 and NFE2L2 mutations are predictive of high rates of local recurrence (LR) after radiotherapy but not surgery. Half of LRs occurred in KEAP1/NFE2L2 mutation tumors, indicating they are major molecular drivers of clinical radioresistance. Next, we functionally evaluate KEAP1/NFE2L2 mutations in our radiotherapy cohort and demonstrate that only pathogenic mutations are associated with radioresistance. Furthermore, expression of NFE2L2 target genes does not predict LR, underscoring the utility of tumor genotyping. Finally, we show that glutaminase inhibition preferentially radiosensitizes KEAP1 mutant cells via depletion of glutathione and increased radiation-induced DNA damage. Our findings suggest that genotyping for KEAP1/NFE2L2 mutations could facilitate treatment personalization and provide a potential strategy for overcoming radioresistance conferred by these mutations.

    View details for DOI 10.1158/2159-8290.CD-20-0282

    View details for PubMedID 33071215

  • A Unique Collateral Artery Development Program Promotes Neonatal Heart Regeneration. Cell Das, S., Goldstone, A. B., Wang, H., Farry, J., D'Amato, G., Paulsen, M. J., Eskandari, A., Hironaka, C. E., Phansalkar, R., Sharma, B., Rhee, S., Shamskhou, E. A., Agalliu, D., de Jesus Perez, V., Woo, Y. J., Red-Horse, K. 2019


    Collateral arteries are an uncommon vessel subtype that can provide alternate blood flow to preserve tissue following vascular occlusion. Some patients with heart disease develop collateral coronary arteries, and this correlates with increased survival. However, it is not known how these collaterals develop or how to stimulate them. We demonstrate that neonatal mouse hearts use a novel mechanism to build collateral arteries in response to injury. Arterial endothelial cells (ECs) migrated away from arteries along existing capillaries and reassembled into collateral arteries, which we termed "artery reassembly". Artery ECs expressed CXCR4, and following injury, capillary ECs induced its ligand, CXCL12. CXCL12 or CXCR4 deletion impaired collateral artery formation and neonatal heart regeneration. Artery reassembly was nearly absent in adults but was induced by exogenous CXCL12. Thus, understanding neonatal regenerative mechanisms can identify pathways that restore these processes in adults and identify potentially translatable therapeutic strategies for ischemic heart disease.

    View details for PubMedID 30686582

  • miRNA-mediated TUSC3 deficiency enhances UPR and ERAD to promote metastatic potential of NSCLC. Nature communications Jeon, Y., Kim, T., Park, D., Nuovo, G. J., Rhee, S., Joshi, P., Lee, B., Jeong, J., Suh, S., Grotzke, J. E., Kim, S., Song, J., Sim, H., Kim, Y., Peng, Y., Jeong, Y., Garofalo, M., Zanesi, N., Kim, J., Liang, G., Nakano, I., Cresswell, P., Nana-Sinkam, P., Cui, R., Croce, C. M. 2018; 9 (1): 5110


    Non-small cell lung carcinoma (NSCLC) is leading cause of cancer-related deaths in the world. The Tumor Suppressor Candidate 3 (TUSC3) at chromosome 8p22 known to be frequently deleted in cancer is often found to be deleted in advanced stage of solid tumors. However, the role of TUSC3 still remains controversial in lung cancer and context-dependent in several cancers. Here we propose that miR-224/-520c-dependent TUSC3 deficiency enhances the metastatic potential of NSCLC through the alteration of three unfolded protein response pathways and HRD1-dependent ERAD. ATF6alpha-dependent UPR is enhanced whereas the affinity of HRD1 to its substrates, PERK, IRE1alpha and p53 is weakened. Consequently, the alteration of UPRs and the suppressed p53-NM23H1/2 pathway by TUSC3 deficiency is ultimately responsible for enhancing metastatic potential of lung cancer. These findings provide mechanistic insight of unrecognized roles of TUSC3 in cancer progression and the oncogenic role of HRD1-dependent ERAD in cancer metastasis.

    View details for PubMedID 30504895

  • Characterization of brain dysfunction induced by bacterial lipopeptides that alter neuronal activity and network in rodent brains. The Journal of neuroscience : the official journal of the Society for Neuroscience Kim, K., Zamaleeva, A. I., Woo Lee, Y., Ahmed, M. R., Kim, E., Lee, H., Raveendra Pothineni, V., Tao, J., Rhee, S., Jayakumar, M., Inayathullah, M., Sivanesan, S., Red-Horse, K., Palmer, T. D., Park, J., Madison, D. V., Lee, H., Rajadas, J. 2018


    The immunopathological states of the brain induced by bacterial lipoproteins have been well-characterized by employing biochemical and histological assays. However, these studies have limitations in determining functional states of damaged brains involving aberrant synaptic activity and network, which makes it difficult to diagnose brain disorders during bacterial infection. To address this, we investigated the effect of Pam3CSK4 (PAM), a synthetic bacterial lipopeptide, on synaptic dysfunction of female mice brains and cultured neurons in parallel. Our functional brain imaging using PET with [18F]-FDG and [18F]-FMZ revealed the brain dysfunction induced by PAM is closely aligned to disruption of neurotransmitter-related neuronal activity and functional correlation in the region of the limbic system rather than to decrease of metabolic activity of neurons in the injection area. This finding was verified by in vivo tissue experiments that analyzed synaptic and dendritic alterations in the regions where PET imaging showed abnormal neuronal activity and network. Recording of synaptic activity also revealed that PAM reorganized synaptic distribution and decreased synaptic plasticity in hippocampus. Further study using in vitro neuron cultures demonstrated that PAM decreased the number of presynapses and the frequency of mEPSC, which suggests PAM disrupts neuronal function by damaging presynapses exclusively. We also showed PAM caused aggregation of synapses around dendrites, which may have caused no significant change in expression level of synaptic proteins while synaptic number and function was impaired by PAM. New findings of this study could provide a useful guide for diagnosis and treatment of brain disorders specific to bacterial infection.SIGNIFICANCE STATEMENTIt is challenging to diagnose brain disorders caused by bacterial infection because neural damage induced by bacterial products involves non-specific neurological symptoms, which is rarely detected by laboratory tests with low spatiotemporal resolution. To better understand brain pathology, it is essential to detect functional abnormalities of brain over time. To this end, we investigated characteristic patterns of altered neuronal integrity and functional correlation between various regions in mice brains injected with bacterial lipopeptides by using PET with a goal to apply new findings to diagnosis of brain disorder specific to bacterial infection. In addition, we analyzed altered synaptic density and function using both in vivo and in vitro experimental models to understand how bacterial lipopeptides impair brain function and network.

    View details for PubMedID 30381406

  • Large-Scale Single-Cell RNA-Seq Reveals Molecular Signatures of Heterogeneous Populations of Human Induced Pluripotent Stem Cell-Derived Endothelial Cells. Circulation research Paik, D. T., Tian, L., Lee, J., Sayed, N., Chen, I. Y., Rhee, S., Rhee, J., Kim, Y., Wirka, R. C., Buikema, J. W., Wu, S. M., Red-Horse, K., Quertermous, T., Wu, J. C. 2018


    Rationale: Human induced pluripotent stem cell-derived endothelial cells (iPSC-ECs) have risen as a useful tool in cardiovascular research, offering a wide gamut of translational and clinical applications. However, inefficiency of the currently available iPSC-EC differentiation protocol and underlying heterogeneity of derived iPSC-ECs remain as major limitations of iPSC-EC technology. Objective: Here we performed droplet-based single-cell RNA-sequencing (scRNA-seq) of the human iPSCs following iPSC-EC differentiation. Droplet-based scRNA-seq enables analysis of thousands of cells in parallel, allowing comprehensive analysis of transcriptional heterogeneity. Methods and Results: Bona fide iPSC-EC cluster was identified by scRNA-seq, which expressed high levels of endothelial-specific genes. iPSC-ECs, sorted by CD144 antibody-conjugated magnetic sorting, exhibited standard endothelial morphology and function including tube formation, response to inflammatory signals, and production of nitric oxide. Non-endothelial cell populations resulting from the differentiation protocol were identified, which included immature and atrial-like cardiomyocytes, hepatic-like cells, and vascular smooth muscle cells. Furthermore, scRNA-seq analysis of purified iPSC-ECs revealed transcriptional heterogeneity with four major subpopulations, marked by robust enrichment of CLDN5, APLNR, GJA5, and ESM1 genes respectively. Conclusions: Massively parallel, droplet-based scRNA-seq allowed meticulous analysis of thousands of human iPSCs subjected to iPSC-EC differentiation. Results showed inefficiency of the differentiation technique, which can be improved with further studies based on identification of molecular signatures that inhibit expansion of non-endothelial cell types. Subtypes of bona fide human iPSC-ECs were also identified, allowing us to sort for iPSC-ECs with specific biological function and identity.

    View details for PubMedID 29986945

  • Nucleic adaptability of heterokaryons to fungicides in a multinucleate fungus, Sclerotinia homoeocarpa FUNGAL GENETICS AND BIOLOGY Kessler, D., Sang, H., Bousquet, A., Hulvey, J. P., Garcia, D., Rhee, S., Hoshino, Y., Yamada, T., Jung, G. 2018; 115: 64–77


    Sclerotinia homoeocarpa is the causal organism of dollar spot in turfgrasses and is a multinucleate fungus with a history of resistance to multiple fungicide classes. Heterokaryosis gives rise to the coexistence of genetically distinct nuclei within a cell, which contributes to genotypic and phenotypic plasticity in multinucleate fungi. We demonstrate that field isolates, resistant to either a demethylation inhibitor or methyl benzimidazole carbamate fungicide, can form heterokaryons with resistance to each fungicide and adaptability to serial combinations of different fungicide concentrations. Field isolates and putative heterokaryons were assayed on fungicide-amended media for in vitro sensitivity. Shifts in fungicide sensitivity and microsatellite genotypes indicated that heterokaryons could adapt to changes in fungicide pressure. Presence of both nuclei in heterokaryons was confirmed by detection of a single nucleotide polymorphism in the β-tubulin gene, the presence of microsatellite alleles of both field isolates, and the live-cell imaging of two different fluorescently tagged nuclei using laser scanning confocal microscopy. Nucleic adaptability of heterokaryons to fungicides was strongly supported by the visualization of changes in fluorescently labeled nuclei to fungicide pressure. Results from this study suggest that heterokaryosis is a mechanism by which the pathogen adapts to multiple fungicide pressures in the field.

    View details for PubMedID 29331685

  • Endothelial deletion of Ino80 disrupts coronary angiogenesis and causes congenital heart disease. Nature communications Rhee, S. n., Chung, J. I., King, D. A., D'amato, G. n., Paik, D. T., Duan, A. n., Chang, A. n., Nagelberg, D. n., Sharma, B. n., Jeong, Y. n., Diehn, M. n., Wu, J. C., Morrison, A. J., Red-Horse, K. n. 2018; 9 (1): 368


    During development, the formation of a mature, well-functioning heart requires transformation of the ventricular wall from a loose trabecular network into a dense compact myocardium at mid-gestation. Failure to compact is associated in humans with congenital diseases such as left ventricular non-compaction (LVNC). The mechanisms regulating myocardial compaction are however still poorly understood. Here, we show that deletion of the Ino80 chromatin remodeler in vascular endothelial cells prevents ventricular compaction in the developing mouse heart. This correlates with defective coronary vascularization, and specific deletion of Ino80 in the two major coronary progenitor tissues-sinus venosus and endocardium-causes intermediate phenotypes. In vitro, endothelial cells promote myocardial expansion independently of blood flow in an Ino80-dependent manner. Ino80 deletion increases the expression of E2F-activated genes and endothelial cell S-phase occupancy. Thus, Ino80 is essential for coronary angiogenesis and allows coronary vessels to support proper compaction of the heart wall.

    View details for PubMedID 29371594

  • Single-cell murine genetic fate mapping reveals bipotential hepatoblasts and novel multi-organ endoderm progenitors Development El Sebae, G. K., Malatos, J. M., Cone, M. E., Rhee, S., Angelo, J. R., Mager, J., Tremblay, K. D. 2018


    The definitive endoderm (DE) is the embryonic germ layer that forms the gut tube and associated organs, including thymus, lungs, liver and pancreas. To understand how individual DE cells furnish gut organs, genetic fate mapping was performed using the Rosa26lacZ Cre-reporter paired with a tamoxifen-inducible DE-specific Cre-expressing transgene. We established a low tamoxifen dose that infrequently induced heritable lacZ expression in a single cell of individual E8.5 mouse embryos and identified clonal cell descendants at E16.5. As expected, only a fraction of the E16.5 embryos contained lacZ-positive clonal descendants and a subset of these contained descendants in multiple organs, revealing novel ontogeny. Furthermore, immunohistochemical analysis was used to identify lacZ-positive hepatocytes and biliary epithelial cells, which are the cholangiocyte precursors, in each clonally populated liver. Together, these data not only uncover novel and suspected lineage relationships between DE-derived organs, but also illustrate the bipotential nature of individual hepatoblasts by demonstrating that single hepatoblasts contribute to both the hepatocyte and the cholangiocyte lineage in vivo.

    View details for DOI 10.1242/dev.168658

    View details for PubMedCentralID PMC6198474

  • Single-cell analysis of early progenitor cells that build coronary arteries. Nature Su, T. n., Stanley, G. n., Sinha, R. n., D'Amato, G. n., Das, S. n., Rhee, S. n., Chang, A. H., Poduri, A. n., Raftrey, B. n., Dinh, T. T., Roper, W. A., Li, G. n., Quinn, K. E., Caron, K. M., Wu, S. n., Miquerol, L. n., Butcher, E. C., Weissman, I. n., Quake, S. n., Red-Horse, K. n. 2018


    Arteries and veins are specified by antagonistic transcriptional programs. However, during development and regeneration, new arteries can arise from pre-existing veins through a poorly understood process of cell fate conversion. Here, using single-cell RNA sequencing and mouse genetics, we show that vein cells of the developing heart undergo an early cell fate switch to create a pre-artery population that subsequently builds coronary arteries. Vein cells underwent a gradual and simultaneous switch from venous to arterial fate before a subset of cells crossed a transcriptional threshold into the pre-artery state. Before the onset of coronary blood flow, pre-artery cells appeared in the immature vessel plexus, expressed mature artery markers, and decreased cell cycling. The vein-specifying transcription factor COUP-TF2 (also known as NR2F2) prevented plexus cells from overcoming the pre-artery threshold by inducing cell cycle genes. Thus, vein-derived coronary arteries are built by pre-artery cells that can differentiate independently of blood flow upon the release of inhibition mediated by COUP-TF2 and cell cycle factors.

    View details for PubMedID 29973725

  • Endothelial cells respond to the direction of mechanical stimuli through SMAD signaling to regulate coronary artery size. Development (Cambridge, England) Poduri, A. n., Chang, A. H., Raftrey, B. n., Rhee, S. n., Van, M. n., Red-Horse, K. n. 2017; 144 (18): 3241–52


    How mechanotransduction intersects with chemical and transcriptional factors to shape organogenesis is an important question in developmental biology. This is particularly relevant to the cardiovascular system, which uses mechanical signals from flowing blood to stimulate cytoskeletal and transcriptional responses that form a highly efficient vascular network. Using this system, artery size and structure are tightly regulated, but the underlying mechanisms are poorly understood. Here, we demonstrate that deletion of Smad4 increased the diameter of coronary arteries during mouse embryonic development, a phenotype that followed the initiation of blood flow. At the same time, the BMP signal transducers SMAD1/5/8 were activated in developing coronary arteries. In a culture model of blood flow-induced shear stress, human coronary artery endothelial cells failed to align when either BMPs were inhibited or SMAD4 was depleted. In contrast to control cells, SMAD4-deficient cells did not migrate against the direction of shear stress and increased proliferation rates specifically under flow. Similar alterations were seen in coronary arteries in vivo Thus, endothelial cells perceive the direction of blood flow and respond through SMAD signaling to regulate artery size.

    View details for PubMedID 28760815

  • cis-regulatory control of Mesp1 expression by YY1 and SP1 during mouse embryogenesis DEVELOPMENTAL DYNAMICS Beketaev, I., Zhang, Y., Weng, K., Rhee, S., Yu, W., Liu, Y., Mager, J., Wang, J. 2016; 245 (3): 379–87


    Mesp1 is critical for early cardiomyocyte differentiation and heart development. We previously observed down-regulation of Mesp1 expression in YY1-ablated mouse embryonic hearts. However, how Mesp1 expression is mediated by YY1 is not well understood.We excised YY1 in the murine embryos using Sox2-cre and found that Mesp1 was down-regulated in the embryonic day (E) 7.5 mutant embryos. Also, YY1 activated the 6 kb Mesp1 regulatory element fused to a luciferase reporter. We identified two putative YY1 binding sites in the proximal promoter region of Mesp1 gene, and found that mutation of these sites significantly reduced YY1-induced activation of the Mesp1 promoter. We also uncovered one cognitive site for SP1, one of the earliest binding partners of YY1 identified. Mutation of this SP1 site repressed SP1-induced activation of the Mesp1 promoter. Moreover, YY1 and SP1 synergistically activated the Mesp1 promoter. Consistently, while Lacz expression driven by the wild-type 6 kb regulatory element of Mesp1 gene was robust in E7.5 mouse embryos, the mutation of these binding sites in the context of this 6 kb sequence substantially reduced the LacZ expression during embryogenesis.YY1 and SP1 independently and cooperatively govern the Mesp1 expression during embryogenesis.

    View details for PubMedID 26384464

  • FGF Signaling is Required for Anterior but not Posterior Specification of the Murine Liver Bud DEVELOPMENTAL DYNAMICS Wang, J., Rhee, S., Palaria, A., Tremblay, K. D. 2015; 244 (3): 431–43


    The definitive endoderm arises as a naive epithelial sheet that produces the entire gut tube and associated organs including the liver, pancreas and lungs. Murine explant studies demonstrate that fibroblast growth factor (FGF) signaling from adjacent tissues is required to induce hepatic gene expression from isolated foregut endoderm. The requirement of FGF signaling during liver development is examined by means of small molecule inhibition during whole embryo culture.Loss of FGF signaling before hepatic induction results in morphological defects and gene expression changes that are confined to the anterior liver bud. In contrast the posterior portion of the liver bud remains relatively unaffected. Because FGF is thought to act as a morphogen during endoderm organogenesis, the ventral pancreas was also examined after FGF inhibition. Although the size of the ventral pancreas is not affected, loss of FGF signaling results in a significantly higher density of ventral pancreas cells.The requirement for FGF-mediated induction of hepatic gene expression differs across the anterior/posterior axis of the developing liver bud. These results underscore the importance of studying tissue differentiation in the context of the whole embryo.

    View details for DOI 10.1002/dvdy.24215

    View details for Web of Science ID 000350479700017

    View details for PubMedID 25302779

    View details for PubMedCentralID PMC4344927

  • Visceral Endoderm Expression of Yin-Yang1 (YY1) Is Required for VEGFA Maintenance and Yolk Sac Development PLOS ONE Rhee, S., Guerrero-Zayas, M., Wallingford, M. C., Ortiz-Pineda, P., Mager, J., Tremblay, K. D. 2013; 8 (3): e58828


    Mouse embryos lacking the polycomb group gene member Yin-Yang1 (YY1) die during the peri-implantation stage. To assess the post-gastrulation role of YY1, a conditional knock-out (cKO) strategy was used to delete YY1 from the visceral endoderm of the yolk sac and the definitive endoderm of the embryo. cKO embryos display profound yolk sac defects at 9.5 days post coitum (dpc), including disrupted angiogenesis in mesoderm derivatives and altered epithelial characteristics in the visceral endoderm. Significant changes in both cell death and proliferation were confined to the YY1-expressing yolk sac mesoderm indicating that loss of YY1 in the visceral endoderm causes defects in the adjacent yolk sac mesoderm. Production of Vascular Endothelial Growth Factor A (VEGFA) by the visceral endoderm is essential for normal growth and development of the yolk sac vasculature. Reduced levels of VEGFA are observed in the cKO yolk sac, suggesting a cause for the angiogenesis defects. Ex vivo culture with exogenous VEGF not only rescued angiogenesis and apoptosis in the cKO yolk sac mesoderm, but also restored the epithelial defects observed in the cKO visceral endoderm. Intriguingly, blocking the activity of the mesoderm-localized VEGF receptor, FLK1, recapitulates both the mesoderm and visceral endoderm defects observed in the cKO yolk sac. Taken together, these results demonstrate that YY1 is responsible for maintaining VEGF in the developing visceral endoderm and that a VEGF-responsive paracrine signal, originating in the yolk sac mesoderm, is required to promote normal visceral endoderm development.

    View details for DOI 10.1371/journal.pone.0058828

    View details for Web of Science ID 000316409800034

    View details for PubMedID 23554936

    View details for PubMedCentralID PMC3598950

  • Effects of trans-10,cis-12 Conjugated Linoleic Acid on Body Composition in Genetically Obese Mice JOURNAL OF MEDICINAL FOOD Hur, S., Whitcomb, F., Rhee, S., Park, Y., Good, D. J., Park, Y. 2009; 12 (1): 56–63


    Conjugated linoleic acid (CLA) has shown a number of biologically beneficial effects, including prevention of obesity. The purpose of this study was to test effects of dietary supplementation of 0.5% trans-10,cis-12 CLA in a high fat diet in neuronal basic helix-loop-helix 2 knock-out animals (N2KO), which is a unique animal model representing adult-onset inactivity-related obesity. Eight wild-type (WT) and eight N2KO female mice were fed either 0.5% trans-10,cis-12 CLA-containing diet or control diet (with 20% soybean oil diet) for 12 weeks. Body weights, food intake, adipose tissue weights, body compositions, and blood parameters were analyzed. Overall, N2KO animals had greater body weights, food intake, adipose tissue weights, and body fat compared to WT animals. CLA supplementation decreased overall body weights and total fat, and the effect of dietary CLA on adipose tissue reduction was greater in N2KO than in WT mice. Serum leptin and triglyceride levels were reduced by CLA in both N2KO and WT animals compared to control animals, while there was no effect by CLA on serum cholesterol. The effect of CLA to lower fat mass, increase lean body mass, and lower serum leptin and triglycerides in sedentary mice supports the possibility of using CLA to prevent or alleviate ailments associated with obesity.

    View details for DOI 10.1089/jmf.2008.0110

    View details for Web of Science ID 000264406200008

    View details for PubMedID 19298196

  • Influence of encapsulation of emulsified lipids with chitosan on their in vivo digestibility FOOD CHEMISTRY Park, G., Mun, S., Park, Y., Rhee, S., Decker, E. A., Weiss, J., McClements, D., Park, Y. 2007; 104 (2): 761–67