• Journal of Korean Neurosurgical Society
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• v.42 no.3
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• pp.205-210
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• 2007

Objective : Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels mediate the hyperpolarization-activated currents (Ih) that participate in regulating neuronal membrane potential and contribute critically to pacemaker activity, promoting synchronization of neuronal networks. However, distinct regional and cellular localization of HCN channels in the brain have not been precisely defined. Aim of this study was to verify the precise cellular location of HCN1 channels in rat cerebellum to better understand the physiological role these channels play in synaptic transmission between CNS neurons. Methods : HCN1 expression in rat brain was analyzed using immunohistochemistry and electron-microscopic observations. Postsynaptic density-95 (PSD-95), otherwise known as locating and clustering protein, was also examined to clarify its role in the subcellular location of HCN1 channels. In addition, to presume the binding of HCN1 channels with PSD-95, putative binding motifs in these channels were investigated using software-searching method. Results : HCN1 channels were locally distributed at the presynaptic terminal of basket cell and exactly corresponded with the location of PSD-95. Moreover, nine putative SH3 domain of PSD-95 binding motifs were discovered in HCN1 channels from motif analysis. Conclusion : Distinct localization of HCN1 channels in rat cerebellum is possible, especially when analyzed in conjunction with the SH3 domain of PSD-95. Considering that HCN1 channels contribute to spontaneous rhythmic action potentials, it is suggested that HCN1 channels located at the presynaptic terminal of neurons may play an important role in synaptic plasticity.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.5
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• pp.480-488
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• 2006

Industrial and economical importance of CP(Cellular Phone) is growing rapidly. Combined with IT technology, CP is one of the most attractive technologies of today. However, unless we find a new breakthrough in the technology, its growth may slow down soon. RT(Robot Technology) is considered one of the most promising next generation technologies. Unlike the industrial robot of the past, today's robots require advanced features, such as soft computing, human-friendly interface, interaction technique, speech recognition object recognition, among many others. In this paper, we present a new technological concept named RCP (Robotic Cellular Phone) which integrates RT and CP in the vision of opening a combined advancement of CP, IT, and RT, RCP consists of 3 sub-modules. They are $RCP^{Mobility}$(RCP Mobility System), $RCP^{Interaction}$, and $RCP^{Integration}$. The main focus of this paper is on $RCP^{Mobility}$ which combines an autonomous navigation system of the RT mobility with CP. Through $RCP^{Mobility}$, we are able to provide CP with robotic functions such as auto-charging and real-world robotic entertainment. Ultimately, CP may become a robotic pet to the human beings. $RCP^{Mobility}$ consists of various controllers. Two of the main controllers are trajectory controller and self-localization controller. While the former is responsible for the wheel-based navigation of RCP, the latter provides localization information of the moving RCP With the coordinates acquired from RFID-based self-localization controller, trajectory controller refines RCP's movement to achieve better navigation. In this paper, a prototype of $RCP^{Mobility}$ is presented. We describe overall structure of the system and provide experimental results on the RCP navigation.

• Molecules and Cells
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• v.39 no.12
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• pp.841-846
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• 2016

Local protein synthesis mediates precise spatio-temporal regulation of gene expression for neuronal functions such as long-term plasticity, axon guidance and regeneration. To reveal the underlying mechanisms of local translation, it is crucial to understand mRNA transport, localization and translation in live neurons. Among various techniques for mRNA analysis, fluorescence microscopy has been widely used as the most direct method to study localization of mRNA. Live-cell imaging of single RNA molecules is particularly advantageous to dissect the highly heterogeneous and dynamic nature of messenger ribonucleoprotein (mRNP) complexes in neurons. Here, we review recent advances in the study of mRNA localization and translation in live neurons using novel techniques for single-RNA imaging.

• Molecules and Cells
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• v.22 no.2
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• pp.203-209
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• 2006

TBP (TATA-binding protein)-related factor 2 (TRF2) regulates transcription during a nuber of cellular processes. We previously demonstrated that it is localized in the cytoplasm and is translocated to the nucleus by DNA-damaging agents. However, the cytoplasmic localization of TRF2 is controversial. In this study, we reconfirmed its cytoplasmic localization in various ways and examined its nuclear migration. Stresses such as heat shock, redox agents, heavy metals, and osmotic shock did not affect localization whereas genotoxins such as methyl methanesulfonate (MMS), cisplatin, etoposide, and hydroxyurea caused it to migrate to the nucleus. Adriamycin, mitomycin C and ${\gamma}$-rays had no obvious effect. We determined optimal conditions for the nuclear migration. The proportions of cells with nuclei enriched for TRF2 were 25-60% and 5-10% for stressed cells and control cells, respectively. Nuclear translocation was observed after 1 h, 4 h and 12 h for cisplatin, etoposide and MMS and hydroxyurea, respectively. The association of TRF2 with the chromatin and promoter region of the proliferating cell nuclear antigen (PCNA) gene, a putative target of TRF2, was increased by MMS treatment. Thus TRF2 may be involved in genotoxin-induced transcriptional regulation.

• Molecules and Cells
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• v.43 no.12
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• pp.1002-1010
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• 2020

Cilia are important eukaryotic cellular compartments required for diverse biological functions. Recent studies have revealed that protein targeting into the proper ciliary subcompartments is essential for ciliary function. In Drosophila chordotonal cilium, where mechano-electric transduction occurs, two transient receptor potential (TRP) superfamily ion channels, TRPV and TRPN, are restricted to the proximal and distal subcompartments, respectively. To understand the mechanisms underlying the sub-ciliary segregation of the two TRPs, we analyzed their localization under various conditions. In developing chordotonal cilia, TRPN was directly targeted to the ciliary tip from the beginning of its appearance and was retained in the distal subcompartment throughout development, whereas the ciliary localization of TRPV was considerably delayed. Lack of intraflagella transport-related proteins affected TRPV from the initial stage of its pre-ciliary trafficking, whereas it affected TRPN from the ciliary entry stage. The ectopic expression of the two TRP channels in both ciliated and non-ciliated cells revealed their intrinsic properties related to their localization. Taken together, our results suggest that sub-ciliary segregation of the two TRP channels relies on their distinct intrinsic properties, and begins at the initial stage of their pre-ciliary trafficking.

• International Journal of Industrial Entomology and Biomaterials
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• v.17 no.2
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• pp.189-195
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• 2008

The sequence of hydroxypyruvate isomerase gene was obtained in NCBI. In this study, the hydroxypyruvate isomerase gene of Bombyx.mori was identified and annotated with bioinformatics tools. The result was confirmed by RT-PCR, prokaryotic expression, mass spectrographic analysis and sub-cellular localization. The hydroxypyruvate isomerase cDNA comtains a 783bp ORF, and has 4 exons. The deduced protein has 260 amino acid residues with the predicted molecular weight of 29169.30 Da, isoelectric point of 6.10, and contains conserved PRK09997 and Hfi domains. The hydroxypyruvate isomerases of Nasonia vitripennis and Bombyx mori have a high homology. Through RTPCR analysis, we found that this transcript was present in testis, ovary, blood-lymph, fat body, midgut, silk gland and tuba Malpighii. This protein was located in cytoplasm through immunohistochemistry. We submitted the cloned gene under the accession number EU344910. The enzyme has been classified under accession number EC 5.3.1.22.

• Animal cells and systems
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• v.15 no.2
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• pp.155-159
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• 2011

Doublecortin (DCX) is microtubule-associated protein and is required for neuronal migration, differentiation and plasticity. In the retina, it is highly expressed between embryonic day 18 (E18) and E20, and is poorly expressed postnatally. In this study, we investigated the expression and cellular localization of DCX in the rat retina following ischemia induced by transiently increasing the intraocular pressure. While DCX immunoreactivity in control retinas was restricted to the outer border of the inner nuclear layer, it appeared in horizontal cell somata and processes in affected retinas. Quantitative evaluation by immunoblotting confirmed that DCX expression continuously increased after ischemia-reperfusion and showed 370% of control protein levels at 4 weeks after ischemic insult. These results suggest that the DCX in horizontal cells might play a role in neurite remodeling or modulating other neurons in ischemic rat retinas.

• Molecules and Cells
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• v.20 no.1
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• pp.119-126
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• 2005

${\alpha}$-Expansins are bound to the cell wall of plants and can be solubilized with an extraction buffer containing 1 M NaCl. Localization of ${\alpha}$-expansins in the cell wall was confirmed by immunogold labeling and electron microscopy. The subcellular localization of vegetative ${\beta}$-expansins has not yet been studied. Using antibodies specific for OsEXPB3, a vegetative ${\beta}$-expansin of rice (Oryza sativa L.), we found that OsEXPB3 is tightly bound to the cell wall and, unlike ${\alpha}$-expansins, cannot be solubilized with extraction buffer containing 1 M NaCl. OsEXPB3 protein could only be extracted with buffer containing SDS. The subcellular localization of the OsEXPB3 protein was confirmed by immunogold labeling and electron microscopy. Gold particles were mainly distributed over the primary cell walls. Immunohistochemistry showed that OsEXPB3 is present in all regions of the coleoptile and root tissues tested.

• Biomolecules & Therapeutics
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• v.15 no.2
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• pp.78-82
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• 2007

The proto-oncogene protein DEK is a nuclear binding phosphoprotein that has been associated with various human diseases including leukemia. Histone acetylation is an important post-translational modification which plays important role in transcriptional regulation. Auto-acetylation of histone acetyltransferase PCAF results in increment of its HAT activity and facilitation of its nuclear localization. In this study, we report that DEK inhibits PCAF auto-acetylation through direct interaction. The C-terminal acidic domains of DEK are responsible for the interaction with PCAF. Using confocal microscopy, we have shown that nuclear localization of PCAF is severely inhibited by DEK. Taken together, our results suggest that DEK may be involved in various cellular signal transduction pathways accommodated by PCAF through the regulation of PCAF auto-acetylation.

• 대한생식의학회:학술대회논문집
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• 2005.06a
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• pp.118-119
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• 2005