Sunkyung Choi | University of North Korean Studies (original) (raw)

Papers by Sunkyung Choi

International Journal of Communication, 2020

Recently, North Korean media has engendered greater connectedness with the outside world. One imp... more Recently, North Korean media has engendered greater connectedness with the outside world. One important goal of the North Korean regime is to create ties with Koreans living outside the country through its official website. Analyzing media representation of a transborder Korean nation, this article discusses the shifts that have occurred in the recent context of the peace process on the Korean peninsula. I argue that the transborder nation- building in North Korean official media reveals a hybrid form of patriotism and nationalism that juxtaposes loyalty to the nation and loyalty to the state. North Korean media thus emerges as a critical site where the two loyalties coexist, demonstrating an attempt to provide the impression of a whole—albeit divided and dispersed—Korean nation.

International Journal of Communication, 2020

Recently, North Korean media has engendered greater connectedness with the outside world. One imp... more Recently, North Korean media has engendered greater connectedness with the outside world. One important goal of the North Korean regime is to create ties with Koreans living outside the country through its official website. Analyzing media representation of a transborder Korean nation, this article discusses the shifts that have occurred in the recent context of the peace process on the Korean peninsula. I argue that the transborder nation-building in North Korean official media reveals a hybrid form of patriotism and nationalism that juxtaposes loyalty to the nation and loyalty to the state. North Korean media thus emerges as a critical site where the two loyalties coexist, demonstrating an attempt to provide the impression of a whole-albeit divided and dispersed-Korean nation.

Scientific Reports

Rbfox RNA-binding proteins play important roles in the regulation of alternative pre-mRNA splicin... more Rbfox RNA-binding proteins play important roles in the regulation of alternative pre-mRNA splicing, but their role in other gene regulatory mechanisms is not well understood. Here, we show that Rbfox2 is a novel constituent of cytoplasmic stress granules, the translational silencing machinery assembled in response to cellular stress. We also show that the RNA binding activity of the Rbfox family protein is crucial for its localization into stress granules. To investigate the role of Rbfox2 in stress granules we used RNA-immunoprecipitation sequencing to identify cytoplasmic transcriptome-wide targets of Rbfox2. We report that a subset of cell cycle-related genes including retinoblastoma 1 is the target of Rbfox2 in cytoplasmic stress granules, and Rbfox2 regulates the retinoblastoma 1 mRNA and protein expression levels during and following stress exposure. Our study proposes a novel function for Rbfox2 in cytoplasmic stress granules. Cells show significant gene-regulatory flexibility that allows them to adjust to external conditions. The ability to control gene expression plays an important role in the adaptation of cells to changes in the environment. Regulation of gene expression at the post-transcriptional level, including the control of pre-mRNA splicing, RNA transport, RNA stability and translation provides a rapid and efficient process by which the proteome of a cell can adapt to environmental changes 1. RNA-binding proteins (RBPs) control various steps of nuclear and cytoplasmic RNA processing at the post-transcriptional level 2. RBP-targeting to a RNA transcript affects RNA fate through various mechanisms that enable specific cellular functions to be established and provides a mechanism for post-transcriptional gene regulation during many biological processes. As RBPs have been implicated at various RNA processing steps and RNA metabolic events, it is therefore important to consider the cellular context in order to understand how RBPs exert effects on target RNA. The RNA-binding Rbfox family is highly conserved with established roles in alternative pre-mRNA splicing regulation 3, 4. The Rbfox family in vertebrates consists of three genes: Rbfox1, Rbfox2, and Rbfox3. Rbfox1 is specifically expressed in heart, skeletal muscle and neuronal tissues, whereas Rbfox2 is widely expressed in many tissues throughout life, from the early embryonic stage to the fully-grown adult stage 5, 6. Rbfox3 expression is only detectable in postmitotic neurons of neural tissues 7. All Rbfox family proteins contain a single RNA-recognition motif (RRM) in the middle of the molecule that binds to the hexanucleotide (U)GCAUG with a high affinity in vitro, and binding of Rbfox proteins to this element has also been well demonstrated in intact cells and tissues 3, 5, 8-14. Numerous reports involving depletion of Rbfox in cultured cells and animal models have shown that the regulation of tissue-specific-splicing by Rbfox is critical to a number of biological processes 13, 15-19. Recent reports show that the role of Rbfox is not limited to regulating alternative splicing in the nucleus but also reveal other nuclear and cytoplasmic functions for Rbfox proteins 20-23. The enrichment of Rbfox binding sites in the 3′ UTR of many mRNAs was confirmed at a genome-wide level, and it has been shown that its targeting to the 3′ UTR stabilizes the target mRNA 12, 20, 24. However, the precise function of Rbfox in the cytoplasm is largely unknown. Moreover recent studies have revealed other RNA binding sequences different from the consensus (U)GCAUG sequence in vitro and in intact cells 14, 22. The interaction between RBPs and RNA granules regulates the stability and translational efficiency of mRNAs and plays an important role in the regulation of protein expression in response to external stimuli 25, 26. Stress granules (SGs) are active assemblies of messenger ribonucleoprotein particles (mRNPs), which are formed in

International Journal of Communication, 2020

Recently, North Korean media has engendered greater connectedness with the outside world. One imp... more Recently, North Korean media has engendered greater connectedness with the outside world. One important goal of the North Korean regime is to create ties with Koreans living outside the country through its official website. Analyzing media representation of a transborder Korean nation, this article discusses the shifts that have occurred in the recent context of the peace process on the Korean peninsula. I argue that the transborder nation- building in North Korean official media reveals a hybrid form of patriotism and nationalism that juxtaposes loyalty to the nation and loyalty to the state. North Korean media thus emerges as a critical site where the two loyalties coexist, demonstrating an attempt to provide the impression of a whole—albeit divided and dispersed—Korean nation.

International Journal of Communication, 2020

Recently, North Korean media has engendered greater connectedness with the outside world. One imp... more Recently, North Korean media has engendered greater connectedness with the outside world. One important goal of the North Korean regime is to create ties with Koreans living outside the country through its official website. Analyzing media representation of a transborder Korean nation, this article discusses the shifts that have occurred in the recent context of the peace process on the Korean peninsula. I argue that the transborder nation-building in North Korean official media reveals a hybrid form of patriotism and nationalism that juxtaposes loyalty to the nation and loyalty to the state. North Korean media thus emerges as a critical site where the two loyalties coexist, demonstrating an attempt to provide the impression of a whole-albeit divided and dispersed-Korean nation.

Scientific Reports

Rbfox RNA-binding proteins play important roles in the regulation of alternative pre-mRNA splicin... more Rbfox RNA-binding proteins play important roles in the regulation of alternative pre-mRNA splicing, but their role in other gene regulatory mechanisms is not well understood. Here, we show that Rbfox2 is a novel constituent of cytoplasmic stress granules, the translational silencing machinery assembled in response to cellular stress. We also show that the RNA binding activity of the Rbfox family protein is crucial for its localization into stress granules. To investigate the role of Rbfox2 in stress granules we used RNA-immunoprecipitation sequencing to identify cytoplasmic transcriptome-wide targets of Rbfox2. We report that a subset of cell cycle-related genes including retinoblastoma 1 is the target of Rbfox2 in cytoplasmic stress granules, and Rbfox2 regulates the retinoblastoma 1 mRNA and protein expression levels during and following stress exposure. Our study proposes a novel function for Rbfox2 in cytoplasmic stress granules. Cells show significant gene-regulatory flexibility that allows them to adjust to external conditions. The ability to control gene expression plays an important role in the adaptation of cells to changes in the environment. Regulation of gene expression at the post-transcriptional level, including the control of pre-mRNA splicing, RNA transport, RNA stability and translation provides a rapid and efficient process by which the proteome of a cell can adapt to environmental changes 1. RNA-binding proteins (RBPs) control various steps of nuclear and cytoplasmic RNA processing at the post-transcriptional level 2. RBP-targeting to a RNA transcript affects RNA fate through various mechanisms that enable specific cellular functions to be established and provides a mechanism for post-transcriptional gene regulation during many biological processes. As RBPs have been implicated at various RNA processing steps and RNA metabolic events, it is therefore important to consider the cellular context in order to understand how RBPs exert effects on target RNA. The RNA-binding Rbfox family is highly conserved with established roles in alternative pre-mRNA splicing regulation 3, 4. The Rbfox family in vertebrates consists of three genes: Rbfox1, Rbfox2, and Rbfox3. Rbfox1 is specifically expressed in heart, skeletal muscle and neuronal tissues, whereas Rbfox2 is widely expressed in many tissues throughout life, from the early embryonic stage to the fully-grown adult stage 5, 6. Rbfox3 expression is only detectable in postmitotic neurons of neural tissues 7. All Rbfox family proteins contain a single RNA-recognition motif (RRM) in the middle of the molecule that binds to the hexanucleotide (U)GCAUG with a high affinity in vitro, and binding of Rbfox proteins to this element has also been well demonstrated in intact cells and tissues 3, 5, 8-14. Numerous reports involving depletion of Rbfox in cultured cells and animal models have shown that the regulation of tissue-specific-splicing by Rbfox is critical to a number of biological processes 13, 15-19. Recent reports show that the role of Rbfox is not limited to regulating alternative splicing in the nucleus but also reveal other nuclear and cytoplasmic functions for Rbfox proteins 20-23. The enrichment of Rbfox binding sites in the 3′ UTR of many mRNAs was confirmed at a genome-wide level, and it has been shown that its targeting to the 3′ UTR stabilizes the target mRNA 12, 20, 24. However, the precise function of Rbfox in the cytoplasm is largely unknown. Moreover recent studies have revealed other RNA binding sequences different from the consensus (U)GCAUG sequence in vitro and in intact cells 14, 22. The interaction between RBPs and RNA granules regulates the stability and translational efficiency of mRNAs and plays an important role in the regulation of protein expression in response to external stimuli 25, 26. Stress granules (SGs) are active assemblies of messenger ribonucleoprotein particles (mRNPs), which are formed in