• Proceedings of the KOSOMBE Conference
• /
• v.1994 no.12
• /
• pp.67-70
• /
• 1994

• BMB Reports
• /
• v.50 no.9
• /
• pp.437-444
• /
• 2017

Different types of eukaryotic cells may adopt seemingly distinct modes of directional cell migration. However, several core aspects are regarded common whether the movement is either ameoboidal or mesenchymal. The region of cells facing the attractive signal is often termed leading edge where lamellipodial structures dominates and the other end of the cell called rear end is often mediating cytoskeletal F-actin contraction involving Myosin-II. Dynamic remodeling of cell-to-matrix adhesion involving integrin is also evident in many types of migrating cells. All these three aspects of cell migration are significantly affected by signaling networks of TorC2, TorC1, and PP2A/B56. Here we review the current views of the mechanistic understanding of these regulatory signaling networks and how these networks affect eukaryotic cell migration.

• Journal of Integrative Natural Science
• /
• v.9 no.3
• /
• pp.171-176
• /
• 2016

Rap1 is a key regulator of cell adhesion and migration. Although increasing evidence indicates that the Rap1 signaling pathway is involved in the process of bone remodeling, the mechanism by which Rap1 regulates osteoblastic differentiation and cell adhesion remains unknown. Here, we investigated the morphological characteristics and osteoblastic differentiation of cells expressing constitutively activated form of Rap1A (Rap1ACA) or Rap1 GTPase activating protein Rap1GAP and found that activated Rap1 induces osteoblastic differentiation and cell adhesion as well as cell spreading. When osteoblastic differentiation was induced, Rap1ACA cells showed considerably higher levels of calcium deposits than the wild-type and Rap1GAP-overexpressing cells did. Rap1ACA cells showed increased spreading and size, as well as strong cell adhesion and significantly decreased growth rates. F-actin staining using phalloidin revealed several thin thread-like filopodia around the protrusions in Rap1ACA cells, which possibly contribute to the increased cell adhesion.

• The Korean Journal of Mycology
• /
• v.51 no.2
• /
• pp.147-153
• /
• 2023

Dark brown leaf molds growing in a vein-limited pattern have been continuously observed on the lower leaf surface of Fatoua villosa in Korea. Fifteen samples deposited in the Korea University herbarium were examined for fungal morphological characterization. Two monoconidial isolates were obtained in 2022, and molecular analysis was performed based on a combined multigene dataset of the internal transcribed spacer (ITS) region and partial actin (actA), translation elongation factor 1-alpha (tef1), and DNA-directed RNA polymerase II second-largest subunit (rpb2). Based on morphological features and molecular phylogenetic analysis, the fungus Pseudocercospora fatouae was identified. To the best of our knowledge, it is the first study reporting the presence of P. fatouae on F. villosa in Korea.

• Journal of Korean society of Dental Hygiene
• /
• v.16 no.3
• /
• pp.471-477
• /
• 2016

Objectives: Fluoride is widely used in the prevention and control of dental caries. The purpose of this study is to examine the biological effects of Sodium fluoride on the proliferation of oral normal cell in vitro(MDPC-23, HaCaT, HGF-1 cells). Methods: The proliferation of normal cells and the cyto-skeletal change of normal cells were assessed by WST-1 assay and F-actin stain assay. The statistical significances of the resulting data were analyzed using SPSS(Window 12.0). Results: The sodium fluoride(0-12 mM) treatment decreased the cell viability in a dose and time dependent manner: HaCaT(6 h): $100{\pm}0$, $98{\pm}0.39$, $82{\pm}2.68$, $75{\pm}0.83$, $69{\pm}1$, $67{\pm}1.42%$(p<0.005); HaCaT(24 h): $100{\pm}0$, $98{\pm}1.85$, $54{\pm}0.64$, $43{\pm}0.4$, $38{\pm}0.32$, $36{\pm}0.13%$(p<0.006), MDPC-23(6 h): $100{\pm}0$, $93{\pm}1.48$, $85{\pm}0.28$, $82{\pm}1.58$, $79{\pm}1.48$, $76{\pm}1.93%$(p<0.009); MDPC-23(24 h): $100{\pm}0$, $91{\pm}1.26$, $58{\pm}0.65$, $49{\pm}1$, $44{\pm}0.74$, $2{\pm}0.05%$(p<0.005), HGF-1(6 h): $100{\pm}0$, $97{\pm}2.93$, $89{\pm}5$, $71{\pm}5.42$, $58{\pm}4.82$, $43{\pm}3.47%$(p<0.009); HGF-1(24 h): $100{\pm}0$, $97{\pm}2.05$, $73{\pm}1.73$, $22{\pm}1.61$, $14{\pm}1.73$, $7{\pm}0.85%$(p<0.005). Thus, changes in cell morphology and disruption of filamentous(F)-actin organization were observed in higher concentration. Conclusions: These results suggest that higher concentrations of fluoride lead to a reduce the number of cells and morphology change of normal cell.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.44 no.3
• /
• pp.219-229
• /
• 2018

The purpose of this study was to investigate the role of the Moringa oleifera (M. oleifera) extract as a cosmetic additive. The tyrosinase and elastase inhibitory effects showed 47% and 39% at $1,000{\mu}g/mL$ concentration, respectively. Also, the collagenase inhibition effect was 31% at $500{\mu}g/mL$ concentration. A cell viability test, measured on macrophage cell (RAW 264.7) and melanoma cell (B16F10) by ethanol extract of M. oleifera, showed 94.2% and 94.8% at $100{\mu}g/mL$ concentration, respectively. In order to confirm anti-inflammatory activity, we examined the inhibitory effects on the production of lipopolysaccharides (LPS)-induced NO in RAW 264.7 cells by Griess assay. As a result, the M. oleifera extract showed a concentration-dependent inhibition of NO production. The protein expression inhibitory effects of M. oleifera extract were measured by western blot at 25, 50, $100{\mu}g/mL$ concentration and the ${\beta}-actin$. Results showed that the expression inhibition rates of the iNOS, COX-2, MITF, TRP-1, TRP-2, tyrosinase protein were decreased by 85.8%, 57.5%, 80.7%, 30%, 29.9%, 23.6% at $100{\mu}g/mL$ concentration, respectively. It was concluded that M. oleifera extracts had the anti-inflammatory and whitening effects and thus could be applied for cosmetics as a natural ingredient.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.10
• /
• pp.6007-6012
• /
• 2013

ANXA2, a member of the annexin family, is overexpressed and plays important roles in tumor development. However, the significance of ANXA2 expression in gastric carcinoma has not been clarified.To elucidate its roles in growth of gastric cancer, ANXA2 expression in SGC-7901 cells was inhibited with a designated siRNA, then cell proliferation, cell cycling, apoptosis and motility were determined by MTT assay, flow cytometry, Hoechst 33342 staining and wound healing assay, respectively. To further assess the behavior of ANXA2 deleted SGC-7901 cells, changes of microstructures were observed under fluorescence microscopy, laser scanning confocal microscopy and electron microscopy. We found that inhibition of ANXA2 expression caused cell proliferation to decrease significantly with G1 arrest, motility to be reduced with changes in pseudopodia/filopodia structure and F-actin and ${\beta}$-tubulin expression, and apoptosis to be enhanced albeit without significance. At the same time, ANXA2 deletion resulted in fewer pseudopodia/filopodia, non-stained areas were increased, contact inhibition among cells reappeared, and expression of F-actin and ${\beta}$-tubulin was decreased, with induction of polymerized disassembled forms. Taken together, these data suggest that ANXA2 overexpression is important to maintain the malignancy of cancer cells, and this member of the annexin family has potential to be considered as a target for the gene therapy of gastric carcinoma.

• Korean Journal of Acupuncture
• /
• v.38 no.3
• /
• pp.140-150
• /
• 2021

Objectives : The increase of osteoclasts could cause osteoporosis and bone-related diseases. Also, the inhibition of osteoclast differentiation is important in treating bone-related diseases. Traditionally, Psoraleae Semen has been used for geriatric diseases, aging and musculoskeletal diseases. The purpose of this study is to investigate the effect of Psoraleae Semen ethanol extract (PS) on osteoclast differentiation and its function. Methods : To confirm the effect of PS on osteoclastogenesis and bone resorption activity, various levels of concentrations of PS (5, 10, 20 and 40 ㎍/ml) were tested on RAW 264.7 cells cultured with RANKL. We measured tartarate-resistant acid phosphatase (TRAP)-positive cells, TRAP activity, pit formation and F-actin ring formation. The expressions of nuclear factor of activated T-cells (NFATc1) and c-Fos were confirmed through western blot and reverse transcription- polymerase chain reaction (RT-PCR). Also, the expression of bone resorption and fusion-related genes in osteoclast was confirmed by RT-PCR. Results : PS decreased the number of TRAP-positive cells and the TRAP activity. In addition, PS significantly inhibited the formation of pit and F-actin ring. Furthermore, PS decreased the expression of osteoclast related genes. Conclusions : PS inhibits osteoclast differentiation and bone resorption ability through inhibition of the expression of osteoclast-related genes. This indicates that PS may be a potential therapeutic agent to osteoporosis by suppressing osteoclastogenesis.

• Microbiology and Biotechnology Letters
• /
• v.48 no.4
• /
• pp.556-563
• /
• 2020

The purpose of this study was to verify the antioxidant and whitening effects of fermented Ambrosia trifida L. extract (ATFE) and to verify its usefulness as a cosmetic material. The antioxidant effects were measured by assessing the electron-donating capacity and 2,2-azino-bis(3-ethyl-benthiazoline-6-sulfonic acid) (ABTS) radical scavenging ability of these extracts. ATFE was shown to have an electron-donation capacity of 68.4% at a concentration of 1000 ㎍/ml. While its ABTS+ radical scavenging ability was shown to be 58.7% at the same concentration. The ATFE tyrosinase inhibitory effect, which is related to skin-whitening, was shown to be 32.35% at a concentration of 1000 ㎍/ml and a cell viability assay using melanoma cells showed a 14.8% reduction in cell viability at a concentration of 100 ㎍/ml. Surviving cells were then used in western blot analyses to evaluate the protein inhibitory effects of ATFE at 25, 50, 100 ㎍/ml where β-actin was used as a positive control. The whitening effects of these extracts were also evaluated by western blot and show that the expression of microphthalmia-associated transcription factors, Tyrosinase-related proteins (TRP)-1, TRP-2 and Tyrosinase were all inhibited, 51.14%, 55.4%, 38.6%, 83.77% respectively, at 100 ㎍/ml ATFE. The efficacy of the whitening effects was verified and the suitability of ATFE as a cosmetic material was assured.

• Carbon letters
• /
• v.22
• /
• pp.42-47
• /
• 2017

In this paper, the in vitro biocompatibility of graphene film (GF) with osteoblasts was evaluated through cell adhesion, viability, alkaline phosphatase activity, F-actin and vinculin expressions, versus graphite paper as a reference material. The results showed that MG-63 cells exhibited stronger cell adhesion, better proliferation and viability on GF, and osteoblasts cultured on GF exhibited vinculin expression throughout the cell body. The rougher and wrinkled surface morphology, higher elastic modulus and easy out-of-plane deformation associated with GF were considered to promote cell adhesion. Also, the biomineralization of GF was assessed by soaking in simulated body fluid, and the GF exhibited enhanced mineralization ability in terms of mineral deposition, which almost pervaded the entire GF surface. Our results suggest that graphene promotes cell adhesion, activity and the formation of bone-like apatite. This research is expected to facilitate a better understanding of graphene-cell interactions and potential applications of graphene as a promising toughening nanofiller in bioceramics used in load-bearing implants.