• 제목/요약/키워드: Ras protein

검색결과 172건 처리시간 0.023초

Spry2 does not directly modulate Raf-1 kinase activity in v-Ha-ras-transformed NIH 3T3 fibroblasts

  • Ahn, Jun-Ho;Eum, Ki-Hwan;Lee, Michael
    • BMB Reports
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    • 제43권3호
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    • pp.205-211
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    • 2010
  • Sprouty (Spry) proteins have previously been suggested as negative regulators of the MAPK pathway through interaction with Raf-1. However, the molecular basis of this inhibition has not been elucidated. In this study, we used cells expressing FLAGtagged Raf-1 with point mutations at known phosphorylation sites to reveal that activation of Raf-1 mutants does not correlate with their degree of interaction with Spry2. The association of Raf-1 with Spry2 in intact cells was further corroborated by immunofluorescence colocalization. Additionally, there was no significant change observed in the strength of interaction between Raf-1 mutants and Spry2 after paclitaxel treatment despite differences in the activation levels of these mutants. Thus, our study provides the evidence that Spry2 does not directly regulate Raf-1 kinase activity, but instead acts as a scaffolding protein that assists interactions between Raf-1 kinase and its direct regulators.

아질산 노출이 흰다리새우, Litopenaeus vannamei의 생존율 및 독성 생리에 미치는 영향 (Effects of nitrite exposure on survival and physiology of white leg shrimp, Litopenaeus vannamei)

  • 김수경;김석렬
    • 한국어병학회지
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    • 제36권2호
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    • pp.361-368
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    • 2023
  • Juveniles of the white leg shrimp Litopenaeus vannamei (Weight 0.18±0.08 g) were exposed to nitrite-N at 0, 25, 50, 100, 200 and 400 mg/L for 72 hours, and the lethal concentration, heamolymph and genes regulation were evaluated. The lethal concentration 50 (LC50) of L. vannamei exposed to nitrite-N was 141.2 mg/L at 25℃ and 33 psu. In Total protein, total cholesterol, and BUN in heamolymph temporarily increased after the start of the experiment and then stabilized, but glucose, an indicator of stress, decreased over time in the entire experimental group, and creatines, an indicator of tissue damage, decreased with nitrite concentration until the first 12 hours. The genes of immune-related showed that masquerade-like serine proteinase(Mas) increased at 50 and 400 ppm for 24 hours, and then gradually decreased depending on concentration. In the case of prophenoloxidase, it was highest at 400 ppm for 40 hours, and other genes(Ras-related nuclear protein, Masquerade-like serine proteinase, proPO-activating enzyme) showed a response for 48 hours and then gradually decreased. The results of this study indicate that exposure to nitrite can affect the survival and hematological physiology of L. vannamei.

Genomewide Expression Profile of Forsythia Suspensa on Lipopolysaccaride-induced Activation in Microglial Cells

  • Sohn, Sung-Hwa;Ko, Eun-Jung;Kim, Yang-Seok;Shin, Min-Kyu;Hong, Moo-Chang;Bae, Hyun-Su
    • Molecular & Cellular Toxicology
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    • 제4권2호
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    • pp.113-123
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    • 2008
  • Microglia, which is the primary immune effector cells in the central nervous system, constitutes the first line of defense against infection and injury in the brain. The goal of this study was to determine the protective (anti-inflammation) mechanisms of forsythia suspense (FS) on LPS-induced activation of BV-2 microglial cells. The effects of FS on gene expression profiles in activated BV-2 microglial cells were evaluated using microarray analysis. BV-2 microglial cells were cultured in a 100mm dish $(1{\times}10^7/dish)$ for 24hr and then pretreated with $1{\mu}g/mL$ FS or left untreated for 30 min. Next, $1{\mu}g/mL$ LPS was added to the samples and the cells were reincubated at $37^{\circ}C$ for 30 min, 1hr, and 3hr. The gene expression profiles of the BV-2 microglial cells varied depending on the FS. The oligonucleotide microarray analysis revealed that MAPK pathway-related genes such as Mitogen activated protein kinase 1 (Mapk1), RAS protein activator like 2 (Rasal2), and G-protein coupled receptor 12 (Gpr12) and nitric oxide biosynthesis-related genes such as nitric oxide synthase 1 (neuronal) adaptor protein (Nos1ap), and dimethylarginine dimethylaminohydrolase 1 (Ddah1) were down regulated in FS-treated BV-2 microglial cells. FS can affect the MAPK pathway and nitric oxide biosynthesis in BV-2 microglial cells.

Differential Gene Expression in Estradiol-3-Benzoate-Treated Liver and Chemically- Induced Hepatocellular Carcinoma

  • KIM , SEYL;KANG, JIN-SEOK;JANG, DONG-DEUK;LEE, KOOK-KYUNG;KIM, SOON-AE;HAN, BEOM-SEOK;PARK, YOUNG-IN
    • Journal of Microbiology and Biotechnology
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    • 제14권6호
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    • pp.1286-1294
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    • 2004
  • In a previous study by the current authors, hepatocellular carcinoma (HCC) was determined to be epidemiologically sex-dependent, and the incidence and multiplicity of HCC found to decrease in estradiol-3 benzoate (EB)-treated F344 rats. Therefore, to ascertain the anticancer mechanism of EB, a commercially available cDNA microarray, with a total of 14,815 cDNA rat gene clones, was used to determine the differentially expressed genes in nontreated livers, EB-treated livers, and diethynitrosolamine (DEN)-induced HCC. In the sequenced experiment, a total of 85 genes were differentially expressed at either two or more times the rate of the normal expression, where 33 genes were downregulated by EB, and 52 genes upregulated. Candidate genes were selected according to significant changes observed in the mRNA expression in the EB-treated livers compared with the nontreated livers, then these genes were filtered according to their different expression patterns in the DEN-induced tumors compared to the estrogen-treated livers. To confirm the microarray data, a real-time PCR analysis was performed for ten selected genes: the H-ras revertant protein 107 (H­rev107), insulin-like growth factor binding protein (lOFBP), parathyroid hormone receptor (PI'HR), SH3 domain binding protein (SH3BP), metallothionein, src-suppressed C-kinase substrate (SSeCK) gene, phosphodiesterase I, CD44, epithelial membrane protein 3 (EMP3), and estrogen receptor a (ERa). The SSeCK and phosphodiesterase I genes were both upregulated in the DEN-induced hepatocarcinomas, yet their possible carcinogenic functions remain unknown. Meanwhile, the other genes were downregulated, including the genes related to growth regulation (IOFBP, H-revI07, ER$\alpha$), adipogenesis inhibition (PTHR), and tumor suppression (metallothionein).

Oncomodulin/Truncated Protamine-Mediated Nogo-66 Receptor Small Interference RNA Delivery Promotes Axon Regeneration in Retinal Ganglion Cells

  • Cui, Zhili;Kang, Jun;Hu, Dan;Zhou, Jian;Wang, Yusheng
    • Molecules and Cells
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    • 제37권8호
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    • pp.613-619
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    • 2014
  • The optic nerve often suffers regenerative failure after injury, leading to serious visual impairment such as glaucoma. The main inhibitory factors, including Nogo-A, oligodendrocyte myelin glycoprotein, and myelin-associated glycoprotein, exert their inhibitory effects on axonal growth through the same receptor, the Nogo-66 receptor (NgR). Oncomodulin (OM), a calcium-binding protein with a molecular weight of an ~12 kDa, which is secreted from activated macrophages, has been demonstrated to have high and specific affinity for retinal ganglion cells (RGC) and promote greater axonal regeneration than other known polypeptide growth factors. Protamine has been reported to effectively deliver small interference RNA (siRNA) into cells. Accordingly, a fusion protein of OM and truncated protamine (tp) may be used as a vehicle for the delivery of NgR siRNA into RGC for gene therapy. To test this hypothesis, we constructed OM and tp fusion protein (OM/tp) expression vectors. Using the indirect immunofluorescence labeling method, OM/tp fusion proteins were found to have a high affinity for RGC. The gel shift assay showed that the OM/tp fusion proteins retained the capacity to bind to DNA. Using OM/tp fusion proteins as a delivery tool, the siRNA of NgR was effectively transfected into cells and significantly down-regulated NgR expression levels. More importantly, OM/tp-NgR siRNA dramatically promoted axonal growth of RGC compared with the application of OM/tp recombinant protein or NgR siRNA alone in vitro. In addition, OM/tp-NgR siRNA highly elevated intracellular cyclic adenosine monophosphate (cAMP) levels and inhibited activation of the Ras homolog gene family, member A (RhoA). Taken together, our data demonstrated that the recombinant OM/tp fusion proteins retained the functions of both OM and tp, and that OM/tp-NgR siRNA might potentially be used for the treatment of optic nerve injury.

Luteolin attenuates migration and invasion of lung cancer cells via suppressing focal adhesion kinase and non-receptor tyrosine kinase signaling pathway

  • Masraksa, Wuttipong;Tanasawet, Supita;Hutamekalin, Pilaiwanwadee;Wongtawatchai, Tulaporn;Sukketsiri, Wanida
    • Nutrition Research and Practice
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    • 제14권2호
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    • pp.127-133
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    • 2020
  • BACKGROUND/OBJECTIVES: Non-small cell lung cancer is mostly recognized among other types of lung cancer with a poor prognosis by cause of chemotherapeutic resistance and increased metastasis. Luteolin has been found to decrease cell metastasis. However, its underlying mechanisms remain unresolved. The objective of this study was to examine the effect (and its mechanism) of luteolin on the migration and invasion of human non-small cell lung cancer A549 cells. MATERIALS/METHODS: Cell viability was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Wound healing and transwell assays were evaluated to assess migration and invasion, respectively. Western blot analysis and immunofluorescence were further performed to investigate the role of luteolin and its mechanisms of action. RESULTS: Administration with up to 40 μM luteolin showed no cytotoxic activity on lung cancer A549 cells or non-cancer MRC-5 cells. Additionally, luteolin at 20-40 μM significantly suppressed A549 cells' migration, invasion, and the formation of filopodia in a concentration-dependent manner at 24 h. This is similar with western blot analysis, which revealed diminished the phosphorylated focal adhesion kinase (pFAK), phosphorylated non-receptor tyrosine kinase (pSrc), Ras-related C3 botulinum toxin substrate 1 (Rac1), cell division control protein 42 (Cdc42), and Ras homolog gene family member A (RhoA) expression levels. CONCLUSIONS: Overall, our data indicate that luteolin plays a role in controlling lung cancer cells' migration and invasion via Src/FAK and its downstream Rac1, Cdc42, and RhoA pathways. Luteolin might be considered a promising candidate for suppressing invasion and metastasis of lung cancer cells.

Anticoagulation and Anticancer Constituents from Eugenia caryophyllata Thunb

  • Han, Kyung-Min;Kim, Dong-Hyun;Ahn, Eun-Mi;Lee, Youn-Hyung;Chung, In-Sik;Kim, Dae-Keun;Kwon, Byoung-Mog;Kim, Sung-Hoon;Baek, Nam-In
    • 한국약용작물학회지
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    • 제15권2호
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    • pp.82-88
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    • 2007
  • From the EtOAc fraction of Eugenia caryophyllata, four compounds were isolated through activity-guided silica gel column chromatography, From the result of spectroscopic data including NMR, MS and IR, the chemical structures of the compounds were determined as 1-allyl-4-hydroxy-3-methoxybezene acetate (eugenol acetate, 1), 1-allyl-4-hydroxy-3-methoxybezene (eugenol, 2), $3{\beta}-hydroxyolean-12-en-28-oic$ acid (oleanolic acid, 3) and $2{\alpha}$, $3{\beta}-dihydroxyolean-12-en-28-oic$ acid (maslinic acid, 4). Compounds 3 and 4 were isolated for the first time from this plant. Also, compounds 1, 2 and 3 exhibited relatively high platelet aggregation inhibitory activity with the $IC_{50}$ values of 0.24, 0.09 and 0.07 mM, respectively. Compound 2 significantly prolonged activated partial thromboplastin time (aPTT) with the value of $124{\pm}11.2$ seconds as compared to the control with the value of $37.5{\pm}2.2$ seconds at the concentration of 50 ${\mu}g/ml$. Compounds 1 and 3 revealed inhibitory activity on farnesyl protein transferase (FPTase) with the $IC_{50}$ values of 0.49 and 0.24 mM and compounds 1 and 2 highly inhibited the growth of rat-H-ras cells with the $Gl_{50}$ values of 6.63 and 5.70 ${\mu}M$, respectively.

SKP2/P27Kip1 pathway is associated with Advanced Ovarian Cancer in Saudi Patients

  • Hafez, Mohamed M;Alhoshani, Ali R;Al-Hosaini, Khaled A;Alsharari, Shakir D;Al Rejaie, Salim S;Sayed-Ahmed, Mohamed M;Al-Shabanah, Othman A
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권14호
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    • pp.5807-5815
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    • 2015
  • Background: Ovarian cancer is the most common gynecological malignancy and constitutes the fifth leading cause of female cancer death. Some biological parameters have prognostic roles in patients with advanced ovarian cancer and their expression may contribute to tumor progression. The aim of this study was to investigate the potential prognostic value of SKP2, genes P27Kip1, K-ras, c-Myc, COX2 and HER2 genes expression in ovarian cancer. Materials and Methods: This study was performed on two hundred formalin fixed paraffin embedded ovarian cancer and normal adjacent tissues (NAT). Gene expression levels were assessed using real time PCR and Western blotting. Results: Elevated expression levels of SKP2, K-ras, c-Myc, HER2 and COX2 genes were observed in 61.5% (123/200), 92.5% (185/200), 74% (148/200), 96 % (192/200), 90% (180/200) and 78.5% (157/200) of cancer tissues, respectively. High expression of SKP2 and down-regulation of P27 was associated with advanced stages of cancer. Conclusions: The association between high expression of c-Myc and SKP2 with low expression of P27 suggested that the Skp2-P27 pathway may play an important role in ovarian carcinogenesis. Reduced expression of P27 is associated with advanced stage of cancer and can be used as a biological marker in clinical routine assessment and management of women with advanced ovarian cancer.

Cross-linking of CD80 and CD86 Diminishes Expression of CD54 on EBV-transformed B Cells through Inactivation of RhoA and Ras

  • Park, Ga-Bin;Kim, Yeong-Seok;Song, Hyun-Keun;Kim, Seong-Han;Park, Dong-Man;Lee, Wang-Jae;Hur, Dae-Young
    • IMMUNE NETWORK
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    • 제11권6호
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    • pp.390-398
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    • 2011
  • Background: Epstein Barr virus (EBV) infected B cells are transformed into lymphoblastoid cell lines. Some researchers suggested some a few similarities between this process and carcinogenesis. We observed the expression of CD80 and CD86, co-stimulatory molecules on EBV-transformed B cells and changes of CD54 expression after stimulation of CD80 and CD86. Methods: CD80 and CD86 were stimulated using anti-CD80 and anti-CD86 monoclonal antibodies. To assess apoptosis and surface protein expression, flow cytometric analysis was performed. Intracellular signal molecules were evaluated by RT-PCR and immunoblot. Morphology and localization of proteins were examined using inverted or confocal microscope. Results: Cross-linking of CD80 and CD86 induced apoptosis and interfered with proliferation of EBV-transformed B cells, and dispersion of clumped cells. We also examined that their stimulation induced ROS accumulation and reduced CD54 expression. Interestingly, we observed that CD80 and CD86 diminished the expression of CD54 in different methods. Both CD80 and CD86 downregulated activation of focal adhesion kinase. CD80 stimulus inhibited CD54 expression through mainly RhoA inactivation, while CD86 down-regulated Ras and JNK phosphorylation. Conclusion: These results suggest that co-stimulatory CD80 and CD86 molecules, expressed EBV-transformed B cells, may play a role in apoptosis and cell adhesion.

콥티스속 근경과 탈지된 클로톤 종자의 혼합 추출물(CP-2)이 난포 Granulosa Cell에 미치는 영향 (Effect of CP-2 Extracted from Coptis and Croton tiglium L. on the Growth and Steroidgenesis of Follicular Granulosa Cells)

  • 김종배;김종배;문정조;한영복;김종배
    • 한국가축번식학회지
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    • 제17권1호
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    • pp.13-19
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    • 1993
  • We investigated the effects of CP-2 extracted from the mixture of Copis and Croton tiglium L, which showed very high cytotoxic effect to the various tumor cells, on the growth and steroidenesis of primary and transformed cell lines PA-GS6 and PO-GRS1 by cotransfectionwith SV40 and Ha ras oncogenes. CP-2 inhibited the growth of PA-GS6 and PO-GRS1 in a dose dependent manner when the growth of them was measured by cell number and by protein content, while CP-2 did not affect the growth of primary granulose cells. Productions of progesterone ofprimary and transformed granulosa cells were stimulated by forskolin, but this stimulatory effect was blocked by treatment of CP-2. Clinical application of CP-2 asa new anti-cancer drug and utilization of transformed granulosa cells as a model system for the screening of anti-cancer drug were also discussed.

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