• 대한의생명과학회지
• /
• 제20권1호
• /
• pp.1-7
• /
• 2014

RNA granules such as Stress Granules (SG) and P-Bodies (PB) are aggregates of translationally stalled messenger ribonucleoprotein (mRNP) complexes induced by a wide range of stresses. Over the past decade, extensive studies described key components of RNA granules, their molecular interactions and signaling pathways require for their assembly and disassembly. However, researches defining their exact roles under stress conditions have not been performed so far, although several studies suggested their roles in neurodegenerative diseases recently. In this review, we provide an introduction about their basic properties, key components, and the dynamic nature for their assembly.

• BMB Reports
• /
• 제52권3호
• /
• pp.196-201
• /
• 2019

The Alu element, the most abundant transposable element, is transcribed to Alu RNA. We hypothesized that the PIWI protein regulates the expression of Alu RNA in retinal pigment epithelial (RPE) cells, where accumulated Alu RNA leads to macular degeneration. Alu transcription was induced in RPE cells treated with $H_2O_2$. At an early stage of oxidative stress, PIWIL4 was translocated into the nucleus; however, subsequently it was sequestered into cytoplasmic stress granules, resulting in the accumulation of Alu RNA. An elevated amount of Alu RNA was positively correlated with the disruption of the epithelial features of RPE via induction of mesenchymal transition. Therefore, we suggest that oxidative stress causes Alu RNA accumulation via PIWIL4 sequestration into the cytoplasmic stress granules.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
• /
• pp.508-511
• /
• 2000

In situ hybridization with fluorescent oligonucleotides(FISH) was used to detect and localize microorganisms in the granules of lab-scale upflow anaerobic sludge blanket(UASB) reactors. An UASB reactor was seeded with mesophilically-grown($35^{\circ}\;C$) granular sludge, and thermophilically($55^{\circ}\;C$) operated by feeding with a synthetic wastewater. Sections of the granules were hybridized with 16S rRNA-targeted oligonucleotide probes for Eubacteria, Archaeabacteria, and specific phylogenetic groups of methanogens. FISH clearly showed the layed structure of thermophilic granules, which was consisted of outer bacterial cells and inner archaeal cells. Methanoseata-, Methanosarcina-like cells were also found to be localized inside the granules. These results demonstrated FISH was useful in studying the spatial organizations of methanogens and in situ morphologies and metabolic functions in thermophilic granular sludges.

• Journal of Species Research
• /
• 제10권1호
• /
• pp.63-71
• /
• 2021

Anteholosticha bergeri and Bakuella granulifera were isolated from soil samples collected from Muuidong and Songdo-dong, Incheon and confirmed new to South Korea. Including these two newly recorded species, 11 species of Anteholosticha and four species of Bakuella have been recorded in South Korea to date. Anteholosticha bergeri was discriminated from congeners by following characters: cortical granules, 12-16 macronuclei, 5-8 midventral pairs, 2-3 pretransverse cirri, 4-6 transverse cirri, and three dorsal kineties. Bakuella granulifera was identified by cortical granules, 5-11 buccal cirri, 2-5 frontoterminal cirri, 2-5 midventral cirri rows, and 8-12 transverse cirri. The Korean A. bergeri population corresponds to the Austrian population, except for the number of marginal and transverse cirri, and the Korean B. granulifera population corresponds to the Namibian population, except for body size. In addition, small subunit ribosomal RNA(18S rRNA) gene sequences from both species were determined.

• Animal Systematics, Evolution and Diversity
• /
• 제29권2호
• /
• pp.144-151
• /
• 2013

Two marine hypotrichous ciliates, Anteholosticha petzi and Ponturostyla enigmatica, were collected from the Yellow Sea and the Korea Strait, respectively, and described using live observation and protargol-impregnated specimens. Furthermore, the nuclear small subunit ribosomal RNA gene of each was sequenced and compared to previously annotated sequences retrieved from the GenBank. Anteholosticha petzi is characterized by 3 frontal cirri (FC), 2 frontoterminal cirri (FTC), 8-12 transverse cirri (TC), 1 buccal cirrus (BC), 9-12 midventral pairs (MP), 3 bipolar dorsal kineties (DK), and 3 types of colorless cortical granules. Ponturostyla enigmatica is characterized by 8 FC, 5 ventral cirri (VC), 5-7 TC, 6-7 marginal rows (MR) on each side, 4 complete and 2-3 partial DK, and greenish cortical granules. This is the first identification and description of these 2 species, A. petzi and P. enigmatica, in South Korea.

• BMB Reports
• /
• 제55권3호
• /
• pp.125-135
• /
• 2022

Continuously renewing the proteome, translation is exquisitely controlled by a number of dedicated factors that interact with the ribosome. The RNA helicase DDX3 belonging to the DEAD box family has emerged as one of the critical regulators of translation, the failure of which is frequently observed in a wide range of proliferative, degenerative, and infectious diseases in humans. DDX3 unwinds double-stranded RNA molecules with coupled ATP hydrolysis and thereby remodels complex RNA structures present in various protein-coding and noncoding RNAs. By interacting with specific features on messenger RNAs (mRNAs) and 18S ribosomal RNA (rRNA), DDX3 facilitates translation, while repressing it under certain conditions. We review recent findings underlying these properties of DDX3 in diverse modes of translation, such as cap-dependent and cap-independent translation initiation, usage of upstream open reading frames, and stress-induced ribonucleoprotein granule formation. We further discuss how disease-associated DDX3 variants alter the translation landscape in the cell.

• 한국재료학회지
• /
• 제20권3호
• /
• pp.155-160
• /
• 2010

In this study, we investigated primary biocompatibility and osteogenic gene expression of porous granular BCP bone substitutes with or without strontium (Sr) doping. In vitro biocompatibility was investigated on fibroblasts like L929 cells and osteoblasts like MG-63 cells using a cell viability assay (MTT) and one cell morphological observation by SEM, respectively. MTT results showed a cell viability percent of L929 fibroblasts, which was higher in Sr-BCP granules (98-101%) than in the non-doped granules (92-96%, p < 0.05). Osteoblasts like MG-63 cells were also found to proliferate better on Sr-doped BCP granules (01-111%) than on the non-doped ones (92-99%, p < 0.05) using an MTT assay. As compared with pure BCP granules, SEM images of MG-63 cells grown on sample surfaces confirmed that cellular spreading, adhesion and proliferation were facilitated by Sr doping on BCP. Active filopodial growth of MG-63 cells was also observed on Sr-doped BCP granules. The cells on Sr-doped BCP granules were well attached and spread out. Gene expression of osteonectin, osteopontin and osteoprotegrin were also evaluated using reverse transcriptase polymerase chain reaction (RT-PCR), which showed that the mRNA phenotypes of these genes were well maintained and expressed in Sr-doped BCP granules. These results suggest that Sr doping in a porous BCP granule can potentially enhance the biocompatibility and bone ingrowth capability of BCP biomaterials.

• Animal Systematics, Evolution and Diversity
• /
• 제27권3호
• /
• pp.220-227
• /
• 2011

The morphology of the two marine urostyloid ciliates, Pseudokeronopsis carnea (Cohn, 1866) and Uroleptopsis citrina Kahl, 1932, in the family Pseudokeronopsidae, collected from the Yellow Sea, and the East Sea, Korea, respectively, were studied using live observation and protargol impregnation. Additionally, the small subunit ribosomal RNA (SSU rRNA) gene was sequenced. These two species are firstly recorded in Korea. The main diagnostic key is as follows. Pseudokeronopsis carnea: body outline elongate-elliptical, brown-reddish or orange-red in colour in vivo; bicorona of 16-24 frontal cirri; one buccal and two frontoterminal cirri; 7-10 transverse cirri; 5-7 dorsal kineties; two types of cortical granules (one orange-red pigment, mainly grouped around cirri and dorsal bristles, arranged in typical rubra-pattern; the other, colourless and blood-cell-shaped, and densely distributed); contractile vacuole in the posterior half of the cell on the left side, usually in posterior 1/3-2/5. Uroleptopsis citrina: body outline elongate-elliptical, lemon-yellow in colour in vivo; two types of cortical granules (one yellow pigment; the other, blood-cell-shaped, densely distributed); bicorona of 12-18 frontal cirri; 2-3 frontoterminal cirri; two midventral rows comprising 26-35 cirri (consisting of anterior paired cirri, non-paired single cirri, and posterior paired cirri); three dorsal kineties. In addition, the SSU rRNA sequences of the two species were compared with public database of these species and consequently, showed high similarity.

• 대한미생물학회지
• /
• 제3권1호
• /
• pp.51-65
• /
• 1968

The site of the synthesis of Japanese encephalitis virus(JEV) in the actinomycin-treated and infecter PS Y15 cells(a porcine kidney stable cell line) was observed by the immunofluorescent antibody technique, acridine orange staining, and the autoradiographic analysis. In the parallel studies by immunofluorescent technique and acridine orange staining it the infected cells, Viral protein(as an antigen) and viral RNA were detected at the same site of cytoplasm. In the autoradiographic analysis, the cytoplasmic labeling of $^3H$-uridine was due to the synthesis of JEV-RNA, while the nucleolus and nucleus were not involved. In the autoradiographic studies on the secton of infected cells, the $^3H$-uridine was frequently incorporated around the cytoplasmic vacuoles. This localization of labeling agreed with the site of acridine orange positive granules. The results suggest that the syntheses of the viral RNA and viral protein occurred in the similar site of cytoplasm of the infected cells, and also the virus particles seem to be assembled in the sites of the viral RNA and protein syntheses.

• Animal Systematics, Evolution and Diversity
• /
• 제36권2호
• /
• pp.113-122
• /
• 2020

From a moss sample, we isolated and identified Notohymena gangwonensis Kim et al., 2019 based on morphological and molecular data. The moss and type population has completely identical 18S rRNA (nuclear small subunit ribosomal RNA) gene sequences and both are highly similar in morphological and morphometric attributes, except for the diameter and arrangement of the cortical granules. Thus, we reexamined the type materials(i.e., micrographs and gDNA) and resulted in finding mistakes made by the authors of the species. Based on these data and supporting materials newly obtained (i.e., internal transcribed spacer [ITS] 1, ITS2, 5.8S, and partial 28S rDNA sequences, and scanning electron micrographs), we provide improved diagnosis of the species to clarify its identity. In addition, a key for Notohymena species is provided.