• 제목/요약/키워드: pRB

검색결과 504건 처리시간 0.037초

6-Aminonicotinamide Induces $G_1$ Arrest by Elevating $p27^{kip1}$ as well as Inhibiting cdk2, Cyclin E and p-Rb in IMR32 Neuroblastoma Cell Line

  • Engliez Souad Ahmad;Park In-Kook
    • Animal cells and systems
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    • 제9권4호
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    • pp.191-198
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    • 2005
  • The effects of 6-aminonicotinamide (6-AN) on viability of IMR32 neuroblastoma cells in the presence of ATP or $NAD^+$ have been investigated. 6-AN caused marked reduction in cell viability and similar observations were also made with cells treated with 6-AN+ATP. However, cells treated with $6-AN+NAD^+$ showed cell viability similar to untreated cells. Morphologically, 6-AN and 6-AN+ATP treated cells showed loss of neurites, polyhedric shapes, shrinkage of cell bodies and formation of lysed cells, while $6-AN+NAD^+$ cells did not show any such changes. The flow cytometry analysis demonstrated that 6-AN increased cell population in $G_0/G_1$ phase and decreased cell population in Sand $G_2/M$ phase following a 72 h exposure. Western blot analysis showed that 6-AN stimulated a substantial increase in the level of the cdk inhibitor $p27^{kip1}$, but lowered the levels of cdk2, cyclin E and p-Rb. However, cdc25A and p53R2 were not significantly affected. Immunofluorscence staining of $p27^{kip1}$, cdk2, cyclin E and p-Rb revealed close correlation between the signal observed in the Western blot analysis. 6AN+ATP treated cells showed similar results obtained with 6-AN treated cells in expression of cdk2, cyclin E, p-Rb proteins and $p27^{kip1}$, $6-AN+NAD^+$ cells showed greater expression of cdk2, cyclin E and p-Rb than those in 6-AN and 6-AN+ATP treated cells. The results suggest that 6-AN induced the $G_0/G_1$ phase arrest in IMR32 neuroblastoma cell lines through the increase of $p27^{kip1}$ and the decrease of cdk2, cyclin E and p-Rb.

인체 신경아세포종에서 cAMP 처리에 의한 pRB의 인산화 억제 및 p21WAF1/CIP1의 유도 (Inhibition of pRB Phosphorylation and Induction of p21WAF1/CIP1 Occur During cAMP-induced Growth Arrest in Human Neuroblastoma Cells)

  • Park, Yung-Hyun;Lee, Sang-Hyeon
    • 생명과학회지
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    • 제13권5호
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    • pp.642-650
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    • 2003
  • 인체 신경아세포종의 성장에 미치는 cAMP의 영향을 조사하기 위하여 Ewing's sarcoma 세포주인 CHP-100 세포에 dibutyry1-cAMP 및 8-bromo-cAMP를 처리하였다. 두 종류의 cAMP analog처리 시간 증가에 따라 CHP-100 세포의 증식이 처리 시간 의존적으로 억제되었으며, 이는 핵의 형태변화 및 DNA 단편화 현상을 수반한 apoptosis 유발과 연관성이 있었다. 또한 DNA flow cytometry 분석결과 cAMP는 세포주기 G1기 특이적 arrest를 유발하였다. cAMP 처리에 의하여 retinoblastoma 단백질(pRB)의 인산화가 억제되었으며, 전사조절인자 E2F-1과의 결합이 증대되었다. cAMP는 cyclin-dependent kinase (Cdk) 2 및 cyclin E 단백질의 발현변화에는 영향을 미치지 않았으나, 그들의 kinase 활성은 처리시간 의존적으로 매우 감소되었다. 또한 cAMP 처리에 의하여 Cdk inhibitor인 $p21^{WAF1/CIP1$의 발현이 증가되었으며, 증가된 p21 단백질은 Cdk2와 강한 결합을 형성하고 있었다. 이상의 결과에서 cAMP의 암세포 성장억제 효과에 pRB 및 p21이 매우 중요한 역할을 함을 알 수 있었다.

OVERCOMING THE NUTRITIONAL LIMITATIONS OF RICE STRAW FOR RUMINANTS 1. UREA AMMONIA TREATMENT AND SUPPLEMENTATION WITH RICE BRAN AND GLIRICIDIA FOR LACTATING SURTI BUFFALOES

  • van der Hoek, R.;Muttetuwegama, G.S.;Schiere, J.B.
    • Asian-Australasian Journal of Animal Sciences
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    • 제1권4호
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    • pp.201-208
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    • 1988
  • Fifty-six lactating Surti buffaloes, fed rice straw, were allocated to seven treatment groups as follows: 1. Straw supplemented with 2% urea (SS) + 1.5kg rice bran (RB) 2. Straw treated with 4% urea in an open stack (TS open) 3. TS open + 1.5 kg RB 4. TS open + 3.0 kg RB 5. TS open + 1.5 kg RB + 3.0 kg Gliricidia (Gl) 6. Straw treated with 4% urea in a closed pit (TS closed) 7. TS closed + 1.5 kg RB + 3.0 kg Gl Milk production, butterfat percentage and liveweight gain of cows and calves were measured and tested with analysis of variance. The results are: - The animals on urea treated straw (group 2) had a higher milk production (p<0.05), higher butterfat production (p<0.05) and less liveweight gain loss (p<0.05) than the animals on urea supplemented straw (group 1). Butterfat percentage also increased by treatment, although not significantly (p>0.05). - Increasing levels of rice bran (groups 3 and 4 compared to 2) increased total milk production and milked quantity of butterfat, while butterfat percentage decreased (p < 0.05). - Milk production increased (p <0.05) with extra rice bran added (group 4 compared to 3), but was not affected (p > 0.05) by Gliricidia addition (group 5 compared to 3). Butterfat percentage dropped with extra rice bran supplement (p <0.05). The lack of response to Gliricidia indicated that protein is not limiting in treated straw, or that Gliricidia protein is partly insoluble. - System of treatment had no effect on milk production (p >0.05), while supplementation with 1.5 kg RB and 3.0 kg Gliricidia increased production and caused a lower butterfat percentage (p <0.05) (groups 2, 5, 6 and 7 compared). A significant (p <0.05) interaction treatment system x supplementation was present. It was concluded, that both treatment and supplementation did affect milk production as well as milk composition. Gliricidia addition gave less effect than rice bran, indicating different requirements for starchy substances in the feed. Treatment of straw does not negatively affect butterfat production, it can increase butterfat production and even butterfat percentage.

미강 페놀산 농축물과 Hydroxycinnamic Acids의 세포내 항당뇨 및 항산화 활성 (Anti-hyperglycemic and Antioxidative Activities of Phenolic Acid Concentrates of Rice Bran and Hydroxycinnamic Acids in Cell Assays)

  • 정은희;하태열;황인경
    • 한국식품영양학회지
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    • 제23권2호
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    • pp.233-239
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    • 2010
  • Phenolic acid concentrates of rice bran(RB-ex) and hydroxycinnamic acids were investigated for their anti-hyperglycemic activities through glucose uptake and glucokinase activity using HepG2 cells and stimulatory effects on insulin secretion using HIT-T15 cells. RB-ex was prepared as an ethylacetate extract after alkaline hydrolysis and hydroxycinnamic acids, found as major compositions of RB-ex, such as ferulic acid(FA), sinapic acid(SA) and p-coumaric acid(p-CA) were investigated to compare with the properties of RB-ex. The properties of glucose uptake in HepG2 cells were examined in the absence of insulin and two different glucose concentrations(5.5 mM and 25 mM). RB-ex and FA showed anti-hyperglycemic activities through the increase of glucose uptake and the stimulation of glucokinase activity in HepG2 cells. RB-ex exhibited higher glucose uptakes with higher glucose concentrations, whereas FA exhibited the same increasing effects on both concentrations of glucose. RB-ex and FA exhibited doubled glucokinase activities relative to control. In the presence of insulin in the 25 mM glucose-containing medium, the levels of glucose uptake were increased in all treatments compared with control. As stimulatory effects of samples on insulin secretion were estimated, RB-ex and FA stimulated insulin secretion at a concentration of 25 ${\mu}g/m{\ell}$ and in particular, FA showed the highest amount of insulin-release in HIT-T15 cells. Antioxidative effects on HIT-T15 cells, RB-ex and hydroxycinnamic acids, excluding p-CA, showed inhibitory activities of 78% to 80% at a concentration of 100 ${\mu}g/m{\ell}$. On the basis of these results, we conclude that RB-ex and FA could help decrease blood glucose levels and prevent the cell damages via antioxidant activity.

Crystal Structure of Dehydrated $Rb^{+}$-Exchanged Zeolite X, $Rb_{71}Na_{21}Si_{100}Al_{92}O_{384}$

  • 이석희;김양;김덕수;Karl Seff
    • Bulletin of the Korean Chemical Society
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    • 제19권1호
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    • pp.98-103
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    • 1998
  • The crystal structure of dehydrated $Rb^+$-exchanged zeolite X, stoichiometry $Rb_{71}Na_{21}-X\; (Rb_{71}Na_{21}Si_{100}Al_{92}O_{384})$ per unit cell, has been determined from single-crystal X-ray diffraction date gathered by counter methods. The structure was solved and refined in the cubic space group Fd3, a=25.007(3) Å at 21(1) ℃. The crystal was prepared by ion exchange in a flowing stream using a 0.05 M aqueous RbOH solution (pH=12.7). The crystal was then dehydrated at 360 ℃ and $2{\times}10^{-6}$ torr for two days. The structure was refined to the final error indices, $R_1=0.047$ and $R_2=0.040$ with 239 reflections for which I> 3σ(I). In this structure, 71 $Rb^+$ ions per unit cell are found at six different crystallographic sites and 21 $Na^+$ ions per unit cell are found at two different crystallographic sites. Four and a half $Rb^+$ ions are located at site Ⅰ, the center of the hexagonal prism. Nine $Rb^+$ ions are found at site Ⅰ' in the sodalite cavity (Rb-O=2.910(15) Å and O-Rb-O=78.1(4)°). Eighteen $Rb^+$ ions are found at site Ⅱ in the supercage (Rb-O=2.789(9) Å and O-Rb-O=92.1(4)°). Two and a half $Rb^+$ ions, which lie at site Ⅱ', are recessed ca. 2.07 Å into the sodalite cavity from their three O(2) oxygen planes (Rb-O=3.105(37) Å and O-Rb-O=80.6(5)°). Thirty-two $Rb^+$ ions are found at site Ⅲ deep in the supercage (Rb-O=2.918(12) Å and O-Rb-O=71.9(4)°), and five $Rb^+$ ions are found at site Ⅲ'. Seven $Na^+$ ions also lie at site Ⅰ. Fourteen $Na^+$ ions are found at site Ⅱ in the supercage (Na-O=2.350(19) Å and O-Na-O=117.5(6)°).

Suppression of Human Prostate Cancer Cell Growth by β-Lapachone via Down-regulation of pRB Phosphorylation and Induction of Cdk Inhibitor p21WAF1/CIP1

  • Choi, Yung-Hyun;Kang, Ho-Sung;Yoo, Mi-Ae
    • BMB Reports
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    • 제36권2호
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    • pp.223-229
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    • 2003
  • The product of a tree (Tabebuia avellanedae) from South America, $\beta$-lapachone, is known to exhibit various pharmacological properties, the mechanisms of which are poorly understood. The aim of the present study was to further elucidate the possible mechanisms by which $\beta$-lapachone exerts its anti-proliferative action in cultured human prostate cancer cells. We observed that the proliferation-inhibitory effect of $\beta$-lapachone was due to the induction of apoptosis, which was confirmed by observing the morphological changes and cleavage of the poly(ADP-ribose) polymerase protein. A DNA flow cytometric analysis also revealed that $\beta$-lapachone arrested the cell cycle progression at the G1 phase. The effects were associated with the down-regulation of the phosphorylation of the retinoblastoma protein (pRB) as well as the enhanced binding of pRB and the transcription factor E2F-1. Also, $\beta$-lapachone suppressed the cyclindependent kinases (Cdks) and cyclin E-associated kinase activity without changing their expressions. Furthermore, this compound induced the levels of the Cdk inhibitor $p21^{WAF1/CIP1}$ expression in a p53-independent manner, and the p21 proteins that were induced by $\beta$-lapachone were associated with Cdk2. $\beta$-lapachone also activated the reporter construct of a p21 promoter. Overall, our results demonstrate a combined mechanism that involves the inhibition of pRB phosphorylation and induction of p21 as targets for $\beta$-lapachone. This may explain some of its anticancer effects.

Sertad1 Induces Neurological Injury after Ischemic Stroke via the CDK4/p-Rb Pathway

  • Li, Jianxiong;Li, Bin;Bu, Yujie;Zhang, Hailin;Guo, Jia;Hu, Jianping;Zhang, Yanfang
    • Molecules and Cells
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    • 제45권4호
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    • pp.216-230
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    • 2022
  • SERTA domain-containing protein 1 (Sertad1) is upregulated in the models of DNA damage and Alzheimer's disease, contributing to neuronal death. However, the role and mechanism of Sertad1 in ischemic/hypoxic neurological injury remain unclear. In the present study, our results showed that the expression of Sertad1 was upregulated in a mouse middle cerebral artery occlusion and reperfusion model and in HT22 cells after oxygen-glucose deprivation/reoxygenation (OGD/R). Sertad1 knockdown significantly ameliorated ischemia-induced brain infarct volume, neurological deficits and neuronal apoptosis. In addition, it significantly ameliorated the OGD/R-induced inhibition of cell viability and apoptotic cell death in HT22 cells. Sertad1 knockdown significantly inhibited the ischemic/hypoxic-induced expression of p-Rb, B-Myb, and Bim in vivo and in vitro. However, Sertad1 overexpression significantly exacerbated the OGD/R-induced inhibition of cell viability and apoptotic cell death and p-Rb, B-Myb, and Bim expression in HT22 cells. In further studies, we demonstrated that Sertad1 directly binds to CDK4 and the CDK4 inhibitor ON123300 restores the effects of Sertad1 overexpression on OGD/R-induced apoptotic cell death and p-Rb, B-Myb, and Bim expression in HT22 cells. These results suggested that Sertad1 contributed to ischemic/hypoxic neurological injury by activating the CDK4/p-Rb pathway.

페레이트를 활용한 아조 염료 Reactive Black 5 분해 연구 (Degradation of Reactive Black 5 by potassium ferrate(VI))

  • ;김일규
    • 상하수도학회지
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    • 제38권1호
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    • pp.17-27
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    • 2024
  • 본 논문은 회분식 반응기에서 습식 산화법으로 합성한 칼륨 페레이트(VI)에 의한 난분해성 아조 염료Reactive Black 5의 분해 과정을 연구하는 것을 목적으로 한다. 수용액에서 RB5의 분해는 pH, Ferrate (VI) 투입량, 초기 농도, 수용액 온도 등 다양한 변수의 조건에서 연구되었다. RB5 경우에는 최대 분해 효율은 pH 7.0에서 63.2%가 달성되었으며, 이 실험 조건에서 얻은 kapp 값은 190.49 M-1s-1으로 나타났다. 온도 또한 가장 중요한 매개 변수 중 하나로 연구되었으며, 그 결과로부터 온도(45℃까지)를 증가시키면 페레이트(VI)에 의한 아조 화합물 염료의 분해 효율이 증가하고, 온도가 45℃를 초과하면 분해 효율이 저하되는 것으로 나타났다.

인체 폐암세포에서 인삼사폐탕에 의한 Cdk inhibitor p27의 발현 증가 및 pRB의 인산화 억제 (Induction of Cdk inhibitor p27 and Inhibition of pRB Phosphorylation by Insamsapye-tang Treatment in Human Lung Cancer A549 Cells)

  • 이민우;서창훈;박철;이원호;최영현;박동일
    • 동의생리병리학회지
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    • 제17권1호
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    • pp.213-219
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    • 2003
  • We investigated the effects of Insamsapye-tang (ISSPT) water extract on the cell proliferation of human lung carcinoma A549 cells. ISSPT treatment resulted in the inhibition of cell proliferation in a concentration-dependent manner. This anti-proliferative effect of A549 cells by ISSSPT treatment was associated with morphological changes such as membrane shrinking and cell rounding up. DNA flow cytometric histograms showed that population of G1 phase of the cell cycle was increased by ISSPT treatment in a concentration-dependent manner. ISSPT treatment induced the levels of tumor suppressor p53 protein and cyclin-dependent kinase (Cdk) inhibitor p27 without significant alteration of cyclins and Cdks expression. In addition, ISSPT treatment resulted in down-regulation of phosphorylated retinoblastoma protein (pRB). However, the levels of p130, the pRB family protein, and transcription factors. E2F-1 and E2F-4. were remained unchanged. The present results indicated that ISSPT-induced inhibition of lung cancer cell proliferation is associated with the blockage of G1/S progression and the induction of apoptosis, and we suggest that ISSPT will be an effective therapeutic agent on human lung cancer.

배추무름병 원인균 분리 및 특성 연구 (Isolation and Characterization of Plant Pathogen that Cause Soft Rot Disease in Napa Cabbage)

  • 권영희;유아영;유종언;강호영
    • 생명과학회지
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    • 제19권8호
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    • pp.1177-1182
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    • 2009
  • 배추 무름병을 대상으로 식물병원균 감염모델을 확립하기 위하여 무름병변을 가진 배추조직으로부터 80개의 독립된 세균집락을 순수 분리하였다. 이들 균을 감염되지 않은 배추 잎의 주맥부위에 접종하여 24${\sim}$48 시간 만에 무름병변을 나타내는 8개의 균주를 1차 선별하였다. 다양한 미생물학적, 생화학적, 형태학적인 시험을 통하여 분석한 결과 서로 다른 특성을 나타내는 균이라고 여겨지는 3개의 균을 최종 선정하였고 이들은 모두 그람 음성균으로 판명되었고 RB1, RB2 및 RB6로 명명하였다. API 20E시험, VITEK 2 COMPACT 분석, 16S rRNA 염기서열 분석 등을 종합할 때 RBl 및 RB2는 Erwinia carotovorum subsp. odoriferum 아종으로, RB6는 Erwinia carotovorum subsp. carotovorum 아종으로 추정되었다. 이들 균들은 $30^{\circ}C$, 생리적 pH인 중성 pH에서 최적생육을 하였다. 이들은 배추의 상처 유무에 상관없이 초기 접종양과 비례하여 무름병을 유발하였으며, 상처가 없는 경우보다 상처가 있는 경우에 더욱 명확한 병변을 유발하였다. RBl의 경우 $8.0{\times}10^8$ CFU/ml, RB2 균주는 $10^9$ CFU/ml, RB6는$4.7{\times}10^6$ CFU/ml에서 최초로 무름 증상을 나타냈다. 이들 균의 숙주 특이성을 관찰하기 위하여 14종의 야채에 접종한 결과 배추, 가지 파프리카에서만 무름병변을 유발하는 숙주 특이성을 나타내었다. 이 연구에서 사용된 실험재료들 및 감염모델은 향후 식물병원균의 감염기작해석에 크게 기여할 것으로 예상된다.