• Molecules and Cells
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• 제39권12호
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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.

• Animal cells and systems
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• 제2권4호
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• pp.529-538
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• 1998

In order to analyze the intracellu1ar localization of specific RNA components of ribonucleoproteins (RNP) in Xenopus oocytes, a modified protocol of whole-mount in situ Hybridization is presented in this paper, Mitochondria specific 12S rRNA probe was used to detect the amplification and distribution of mitochondria in various stages of the oocyte life cycle, and the results were found to be consistent with previously known distribution of mitochondria. The results with other specific probes (U1 and U3 small nuclear RNAs, and 5S RNA) also indicate that this procedure is generally effective in localizing RNAs in RNP complexes even inside organelles. In addition, the RNA component of RNase MRP, the RNP with endoribo-nuclease activity, localize to the nucleus in various stages of the oocyte life cycle. Some of MRP RNA, however, were found to be localized to the special population of mitochondria near the nucleus, especially in the active stage of mitochondrial amplification. It suggests dual localization of RNase MRP in the nucleus and mitochondria, which is consistent with the proposed roles of RNase MRP in mitochondrial DNA replication and in rRNA processing in the nucleolus.

• 미생물학회지
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• 제44권2호
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• pp.105-109
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• 2008

발아효모 Saccharomyces cerevisiae의 핵공단백질인 Nic96 단백질과 유사성을 보이는 분열효모 Schizosaccharomyces pombe의 Nup97의 기능과 세포 내 위치를 조사하였다. nup97을 과 발현시켰을 때는 생장과 $poly(A)^{+}$ RNA의 분포에 별다른 이상을 보이지 않았다. 하지만, $kan^{r}$ 유전자를 이용하여 제작한 ${\Delta}nup97$ 결실돌연변이는 nup97의 발현이 억제되면, $poly(A)^{+}$ RNA가 핵 안에 축적되었고 비정상적인 DNA 분포를 보였으며 결국 생장하지 못했다. 한편, Nup97p의 N말단 또는 C말단에 GFP를 붙인 Nup97-GFP 융합단배질의 세포 내 위치를 확인하고자 하였다. 이러한 융합단백질들이 ${\Delta}nup97$ 결실돌연변이의 생장결함을 정상적으로 상보하는 것을 확인하고, nup97-GFP 유전자를 염색체의 nup97 유전자 위치에 삽입한 균주를 제작하였다. 자신의 프로모터에서 발현된 Nup97-GFP 융합단백질은 정상적인 기능을 보였으며, 핵막 주위에 점점 이 위치하였다. 이와 같은 결과들은 Nup97 단백질 역시 핵공단배질로 mRNA의 핵에서 세포질로의 이동에 중요하다는 것을 시사한다.

• BMB Reports
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• 제46권2호
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• pp.65-72
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• 2013

In situ detection of RNAs is becoming increasingly important for analysis of gene expression within and between intact cells in tissues. International genomics efforts are now cataloging patterns of RNA transcription that play roles in cell function, differentiation, and disease formation, and they are demon-strating the importance of coding and noncoding RNA transcripts in these processes. However, these techniques typically provide ensemble averages of transcription across many cells. In situ hybridization-based analysis methods complement these studies by providing information about how expression levels change between cells within normal and diseased tissues, and they provide information about the localization of transcripts within cells, which is important in understanding mechanisms of gene regulation. Multi-color, single-molecule fluorescence in situ hybridization (smFISH) is particularly useful since it enables analysis of several different transcripts simultaneously. Combining smFISH with immunofluorescent protein detection provides additional information about the association between transcription level, cellular localization, and protein expression in individual cells.

• BMB Reports
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• 제43권10호
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• pp.677-682
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• 2010

Kv4.2, a pore-forming $\alpha$-subunit of voltage-gated A-type potassium channels, is expressed abundantly in the soma and dendrites of hippocampal neurons, and is responsible for somatodendritic $I_A$ current. Recent studies have suggested that changes in the surface levels of Kv4.2 potassium channels might be relevant to synaptic plasticity. Although the function and expression of Kv4.2 protein have been extensively studied, the dendritic localization of Kv4.2 mRNA is not well described. In this study, Kv4.2 mRNAs were shown to be localized in the dendrites near postsynaptic regions. The dendritic transport of Kv4.2 mRNAs were mediated by microtubule-based movement. The 500 nucleotides of specific regions within the 3'-untranslated region of Kv4.2 mRNA were found to be necessary and sufficient for its dendritic localization. Collectively, these results suggest that the dendritic localization of Kv4.2 mRNAs might regulate the dendritic surface level of Kv4.2 channels and synaptic plasticity.

• Plant Biotechnology Reports
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• 제5권3호
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• pp.289-295
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• 2011

The SpoU family of proteins catalyzes the methylation of transfer RNAs (tRNAs) and ribosomal RNAs (rRNAs). We characterized a putative tRNA/rRNA methyltransferase, VaSpoU1 of the SpoU family, from Viscum album (mistletoe). VaSpoU1 and other plant SpoU1s exhibit motifs of the SpoU methylase domain that are conserved with bacterial and yeast SpoU methyltransferases. VaSpoU1 transcripts were detected in the leaves and stems of V. album. VaSpoU1-GFP fusion proteins localized to both chloroplasts and mitochondria in Arabidopsis protoplasts. Sequence analysis similarly predicted that the plant SpoU1 proteins would localize to chloroplasts and mitochondria. Interestingly, mitochondrial localization of VaSpoU1 was inhibited by the deletion of a putative N-terminal presequence in Arabidopsis protoplasts. Therefore, VaSpoU1 may be involved in tRNA and/or rRNA methylation in both chloroplasts and mitochondria.

• Biomolecules & Therapeutics
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• 제30권1호
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• pp.64-71
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• 2022

Norovirus (NV) is the most common cause of viral gastroenteritis, with the potential to develop into a fatal disease in those who are immuno-compromised, and effective vaccines and treatments are still non-existent. In this study, we aimed to elucidate the molecular mechanism of the previously identified NV replication inhibitor utilizing a vinyl-stilbene backbone, AC-1858. First, we confirmed the inhibition of the NV RNA replication by a structural analog of AC-1858, AC-2288 with its exclusive cytoplasmic sub-cellular localization. We further validated the induction of one specific host factor, the phosphorylated form of heat shock factor (HSF)-1, and its increased nuclear localization by AC-1858 treatment. Finally, we verified the positive and negative impact of the siRNA-mediated downregulation and lentivirus-mediated overexpression of HSF-1 on NV RNA replication. In conclusion, these data suggest the restrictive role of the host factor HSF-1 in overall viral RNA genome replication during the NV life cycle.

• 한국동물학회지
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• 제37권3호
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• pp.304-310
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• 1994

Using in situ hybridization, we have mapped the anatomical localization of perikarya containing myNA that codes for sonadotropin releasing hormone (GnRH) in the brains of female frogs, R. dybowskii. DNA olisomers, with sequences complementary to the GnRH portion of pro-GnRH myNA sequence, were synthesized and hybridized to paraformaldehvde-fixed, sagittal sections of the whole brain stem. The distribution of the GnRH mRNA containing cell bodies was similar to that described for GnRH peptide by immunohistochemistrv. That is, cells containing GnRH mRNA were observed in the medial septal area, anterior preoptic area, ventromedial hvpothalamus and infundibular regions. However, another cell groups which contains GnRH mRNAs were also detected by in situ hybridization in the bed nucleus of hippocampal commissure, preoptic area, nucleus infundibularis dorsalis, mesencephalic nuclei and intermediolateral cell column of spinal cord areas. These results demonstrate the feasibility of using in situ hybridization as a strategy to study the distribution of GnRH neurons and the detection of GnRH gene expression in the vertebrates.

• The Plant Pathology Journal
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• 제29권4호
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• pp.454-459
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• 2013

The Potexvirus Alternanthera mosaic virus (AltMV) has multifunctional triple gene block (TGB) proteins, among which our studies have focused on the properties of the TGB1 protein. The TGB1 of AltMV has functions including RNA binding, RNA silencing suppression, and cell-to-cell movement, and is known to form homologous interactions. The helicase domains of AltMV TGB1 were separately mutated to identify which regions are involved in homologous TGB1 interactions. The yeast two hybrid system and Bimolecular Fluorescence Complementation (BiFC) in planta were utilized to examine homologous interactions of the mutants. Helicase motif I of AltMV TGB1 was found to be critical to maintain homologous interactions. Mutations in the remaining helicase motifs did not inhibit TGB1 homologous interactions. In the absence of homologous interaction of TGB1, subcellular localization of helicase domain I mutants showed distinctively different patterns from that of WT TGB1. These results provide important information to study viral movement and replication of AltMV.

• Animal cells and systems
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• 제5권3호
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• pp.263-266
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• 2001

Metallothionein (MT) is induced in the regenerating rat liver. We have investigated expression of MT gene by RT PCR as well as specific localization of MT by immunocytochemistry in regenerating rat liver after partial hepatectomy (PH). MT mRNA level started to increase from 1 h and reached the peak at 8 h after PH. The level decreased gradually by 24 h, and became similar to that of control group. In the immunocytochemical study, in all groups treated with primary antibody, immunogold particles indicating the presence of MT were evenly distributed throughout both cytoplasm and nucleus of the rat hepatocytes. Within the nucleus, the gold particles appeared to be intensely localized in the areas of euchromatin and nucleolus. Within the cytoplasm, gold particles did not seem to adhere to mitochondria or Iysosomes, but were freely distributed. However, rough endoplasmic reticulum was the obvious compartment on which the gold particles were localized. Time course of MT immunoreactivity revealed that distribution of gold particles in hepatocytes increased gradually by 24 h, and decreased at 48 h after PH. Briefly, PH resulted in the sharpest increase in the expression of MT mRNA at 8 h and in the immunoreactivity of MT at 24 h, respectively. It is suggested that the increase of MT mRNA expression, the intensity of immunoreactivity and the specific localization of MT may be associated with the compensatory cell proliferation followed by PH.