Publications by authors named "Junsik Choi"

Three-dimensional (3D) printing of hydrogels offers promising potential for creating intricate, customizable structures with superior elasticity, softness, and biocompatibility. However, due to their high-water content, hydrogels often suffer from reduced mechanical strength, which is further decreased when they absorb water, limiting their use in environments requiring high mechanical durability. To address this, we developed a novel 3D printing technique to fabricate bacterial cellulose (BC) nanofiber-reinforced hydrogels, which we term sheet-laminated additive manufacturing (SLAM).

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Arabidopsis lamin analogs CROWDED NUCLEIs (CRWNs) are necessary to maintain nuclear structure, genome function, and proper plant growth. However, whether and how CRWNs impact reproduction and genome-wide epigenetic modifications is unknown. Here, we investigate the role of CRWNs during the development of gametophytes, seeds, and endosperm, using genomic and epigenomic profiling methods.

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The inkjet printing is a simple method to develop pattern-controlled 2D metal-organic frameworks (MOFs) due to its cost-effectiveness and ease of operation. Despite the sophisticated structures of MOF crystals, the MOF surfaces are easily contaminated by the adsorption of an ink solution, and the printing nozzle can be clogged by the aggregates of MOFs during printing. Unlike the mixture inks of MOFs and a carrier medium, the surface-specific patterning by in situ synthesis provides the film surface with the controlled patterns of an MOF single layer having different morphologies of MOFs without changing the ink cartridges.

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A hydrochromic composite film was fabricated by incorporating silica nanoparticles (SiNPs) with cellulose nanofibers (CNFs). The CNF/SiNP composite film underwent a reversible change in transparency in response to external moisture variation. The CNFs improved the dimensional stability of the CNF/SiNP composite film and induced morphological differences in SiNP agglomerates, which control the water vapor condensation in a porous film.

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The nuclear lamina, a sub-nuclear protein matrix, maintains nuclear structure and genome function. Here, we investigate the role of Arabidopsis lamin analogs CROWDED NUCLEIs during gametophyte and seed development. We observed defects in mutant seeds, including seed abortion and reduced germination rate.

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The nuclear lamina in plant cells is composed of plant-specific proteins, including nuclear matrix constituent proteins (NMCPs), which have been postulated to be functional analogs of lamin proteins that provide structural integrity to the organelle and help stabilize the three-dimensional organization of the genome. Using genomic editing, we generated alleles for the three genes encoding NMCPs in cultivated tomato (Solanum lycopersicum) to determine if the consequences of perturbing the nuclear lamina in this crop species were similar to or distinct from those observed in the model Arabidopsis thaliana. Loss of the sole NMCP2-class protein was lethal in tomato but is tolerated in Arabidopsis.

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The free-form fabrication of networked bacterial cellulose (BC) structures was available using a particle matrix and a bioink embedding bacteria. However, the mechanical strength of such BC hydrogel structures does not satisfy the requirements for biomedical applications that require high toughness and elasticity. Here, we adopt the freeze-thaw process with a water-soluble polymer to form a crystalline structure around the BC nanofibers.

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The plant nuclear lamina utilizes distinct and highly divergent proteins to mediate chromatin interactions at the nuclear edge. In this issue of Developmental Cell, Tang et al. show that members of PNET2, a family of inner nuclear membrane proteins in Arabidopsis, are capable of binding histones and are involved in large-scale genome organization.

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The periphery in animal nuclei is generally considered to be a transcriptionally repressive environment. Recent studies indicate that chromatin-based mechanisms establish a similar situation in plant nuclei. We demonstrated recently that the loss of CRWN nuclear lamina proteins in Arabidopsis leads to the misregulation of a group of genes involved in plant defense.

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In this paper, we propose a novel method for magnetic resonance imaging based Alzheimer's disease (AD) or mild cognitive impairment (MCI) diagnosis that systematically integrates voxel-based, region-based, and patch-based approaches into a unified framework. Specifically, we parcellate the brain into predefined regions based on anatomical knowledge (i.e.

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Electronic textiles (e-textiles) are being developed because of their potential applications in wearable and flexible electronics. However, complex procedures and chemical agents are required to synthesize carbon-based e-textiles. Pyroprotein-based e-textiles, obtained by the pyrolysis of silk proteins, consume large amounts of time and energy due to the high-temperature process (from 800 to 2800 °C).

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The chloroplast stromal CLP protease system is essential for growth and development. It consists of a proteolytic CLP core complex that likely dynamically interacts with oligomeric rings of CLPC1, CLPC2, or CLPD AAA chaperones. These ATP-dependent chaperones are predicted to bind and unfold CLP protease substrates, frequently aided by adaptors (recognins), and feed them into the proteolytic CLP core for degradation.

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Lung cancer is a global and dangerous disease, and its early detection is crucial for reducing the risks of mortality. In this regard, it has been of great interest in developing a computer-aided system for pulmonary nodules detection as early as possible on thoracic CT scans. In general, a nodule detection system involves two steps: (i) candidate nodule detection at a high sensitivity, which captures many false positives and (ii) false positive reduction from candidates.

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Defects in the nuclear lamina of animal cell nuclei have dramatic effects on nuclear structure and gene expression as well as diverse physiological manifestations. We report that deficiencies in CROWDED NUCLEI (CRWN), which are candidate nuclear lamina proteins in Arabidopsis (), trigger widespread changes in transcript levels and whole-plant phenotypes, including dwarfing and spontaneous cell death lesions. These phenotypes are caused in part by ectopic induction of plant defense responses via the salicylic acid pathway.

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