• 제목/요약/키워드: Cell division cycle

검색결과 332건 처리시간 0.026초

A conditional lethal mutation of a nucleoporin gene, NUP49 in saccharomyces cerevisiae

  • Lee, Youn-Soo;Song, Young-Ja;Kyung, Hwang-Mi;Lee, Woo-Bok;Kim, Jin-Mi
    • Journal of Microbiology
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    • 제35권3호
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    • pp.234-238
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    • 1997
  • Conditional lethal mutation nup49-1 of a nuclear pore complex component gene was constructed in Saccharomyces cerevisiae. This mutation deleted one third of the essential NUP49 gene at the carboxy-terminal, but retained 13 repeats of the highly conserved GLFG domain. The nup49-1 mutant strain was viable with a slow-growth phenotype, indicating that the C-terminal is dispensable at normal growth temperature. This strain exhibited both temperature-sensitivity at 37.deg.C and cold-sensitivity at 16.deg.C. Temperature shift experiments revealed that the arrest phenotype at 37.deg.C was random in the cell division cycle. The nup49-1 mutation was tested to be recessive and is expected to be useful for the functional analysis of nuclear pore complex proteins as well as for studies of nuclear transport systems.

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Sphingosine-1-phosphate Inhibits Human Keratinocyte Proliferation via Akt/PKB Inactivation

  • Kim, Dong-Seok;Kim, Sook-Young;Kim, Kyu-Han;Park, Kyoung-Chan
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.76.2-76.2
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    • 2003
  • Although sphingosine-1-phosphate (S1P) is a well-known mitogen, our results show that S1P potently inhibits keratinocyte proliferation, and that this leads the inhibition of DNA synthesis. Interestingly, the prolonged activation of extracellular signal-regulated protein kinase (ERK) and the transient inactivation of Akt/protein kinase B (PKB) were also oberved in concert with the inhibition of keratinocyte proliferation by S1P. To further verify the anti-proliferative action of S1P, we examined changes in cell cycle related proteins. (omitted)

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Growth-Dependent Variations in Antioxidant and Redox Enzyme Activities of Schizosaccharomyces pombe

  • Cho, Young-Wook;Park, Eun-Hee;Ahn, Ki-Sup;Kim, Dae-Myung;Lim, Chang-Jin
    • BMB Reports
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    • 제34권3호
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    • pp.278-283
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    • 2001
  • Antioxidant and redox enzyme activities are known to be involved in the cellular responses to various stresses. Their variations were observed according to the growth cycle of the fission yeast Schizosaccharomyces pombe. Peroxidase activity appeared to be notably higher in the early exponential phase than in the mid-exponential and stationary phases. However, catalase activity showed a variation pattern resembling the growth curve. Glutathione S-transferase activity was higher in the early exponential and late stationary phases. Activities of the two redox enzymes, thioredoxin and thioltransferase (glutaredoxin), were high in the stationary phase. However, their activities appeared to increase from the early exponential to mid-exponential phase. Total glutathione content had a varying pattern similar to that of thioredoxin and thioltransferase. However, its content in the early exponential phase was high. These results propose that antioxidant and redox enzymes tested are also involved in the mechanism of cell growth.

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Molecular weight-associated cellular response to silk fibroin fragments demonstrated in MG63 cells

  • Jo, You-Young;Kweon, HaeYong;Kim, Seong-Gon
    • International Journal of Industrial Entomology and Biomaterials
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    • 제35권1호
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    • pp.7-13
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    • 2017
  • In this study, changes in gene expression after administration of silk fibroin fragments ($size{\approx}30kDa$) were evaluated in MG63 cells using a cDNA microarray assay. In addition, the level of alkaline phosphatase (ALP) activity and cellular proliferation in the group administered moderately sized silk fibroin fragments ($size{\approx}30kDa$) (MSF) were compared to those in the group administered smaller silk fibroin fragments (size < 1 kDa) (SSF). The results of the cDNA microarray assay show increased expression of genes that are related to the cell cycle and inflammation. ALP, bone morphogenetic protein-7, bone morphogenetic protein receptor type IA, and runt-related transcription factor 2 exhibited significantly lower expression compared to control cells (fold ratio < 0.5). Relative ALP activity of the $100{\mu}g/mL$ MSF group was significantly lower than that of the SSF group (P < 0.05). Thus, the MSF group showed increased expression of genes associated with cellular proliferation and inflammation but decreased expression of genes associated with osteogenesis.

폐 결절성 림프구양 증식증 (Pulmonary Nodular Lymphoid Hyperplasia)

  • 구현경;김서윤;박성수;이연주;이지연;정진행;이재호;이춘택;윤호일
    • Tuberculosis and Respiratory Diseases
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    • 제69권3호
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    • pp.212-216
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    • 2010
  • Nodular lymphoid hyperplasia is a very rare benign disease and usually shows consolidation on chest X-ray with symptoms of pneumonia due to the proliferation of lymphoid cells in the lung parenchyma. It is common for patients to be diagnosed with pneumonia and treated with antibiotics, but patients often enter a cycle of repeated improvement, followed by aggravation of symptoms. At this point, surgical diagnostic tools are considered in order to differentiate between malignant disease and interstitial lung disease. Here, we report 2 cases of patients with nodular lymphoid hyperplasia and review the associated references.

The Plant Growth-Promoting Fungus Aspergillus ustus Promotes Growth and Induces Resistance Against Different Lifestyle Pathogens in Arabidopsis thaliana

  • Salas-Marina, Miguel Angel;Silva-Flores, Miguel Angel;Cervantes-Badillo, Mayte Guadalupe;Rosales-Saavedra, Maria Teresa;Islas-Osuna, Maria Auxiliadora;Casas-Flores, Sergio
    • Journal of Microbiology and Biotechnology
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    • 제21권7호
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    • pp.686-696
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    • 2011
  • To deal with pathogens, plants have evolved sophisticated mechanisms including constitutive and induced defense mechanisms. Phytohormones play important roles in plant growth and development, as well as in the systemic response induced by beneficial and pathogen microorganisms. In this work, we identified an Aspergillus ustus isolate that promotes growth and induces developmental changes in Solanum tuberosum and Arabidopsis thaliana. A. ustus inoculation on A. thaliana and S. tuberosum roots induced an increase in shoot and root growth, and lateral root and root hair numbers. Assays performed on Arabidopsis lines to measure reporter gene expression of auxin-induced/ repressed or cell cycle controlled genes (DR5 and CycB1, respectively) showed enhanced GUS activity, when compared with mock-inoculated seedlings. To determine the contribution of phytohormone signaling pathways in the effect elicited by A. ustus, we evaluated the response of a collection of hormone mutants of Arabidopsis defective in auxin, ethylene, cytokinin, or abscisic acid signaling to the inoculation with this fungus. All mutant lines inoculated with A. ustus showed increased biomass production, suggesting that these genes are not required to respond to this fungus. Moreover, we demonstrated that A. ustus synthesizes auxins and gibberellins in liquid cultures. In addition, A. ustus induced systemic resistance against the necrotrophic fungus Botrytis cinerea and the hemibiotrophic bacterium Pseudomonas syringae DC3000, probably through the induction of the expression of salicylic acid, jasmonic acid/ethylene, and camalexin defense-related genes in Arabidopsis.

JAEA'S VHTR FOR HYDROGEN AND ELECTRICITY COGENERATION : GTHTR300C

  • Kunitomi, Kazuhiko;Yan, Xing;Nishihara, Tetsuo;Sakaba, Nariaki;Mouri, Tomoaki
    • Nuclear Engineering and Technology
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    • 제39권1호
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    • pp.9-20
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    • 2007
  • Design study on the Gas Turbine High Temperature Reactor 300-Cogeneration (GTHTR300C) aiming at producing both electricity by a gas turbine and hydrogen by a thermochemical water splitting method (IS process method) has been conducted. It is expected to be one of the most attractive systems to provide hydrogen for fuel cell vehicles after 2030. The GTHTR300C employs a block type Very High Temperature Reactor (VHTR) with thermal power of 600MW and outlet coolant temperature of $950^{\circ}C$. The intermediate heat exchanger (IHX) and the gas turbine are arranged in series in the primary circuit. The IHX transfers the heat of 170MW to the secondary system used for hydrogen production. The balance of the reactor thermal power is used for electricity generation. The GTHTR300C is designed based on the existing technologies of the High Temperature Engineering Test Reactor (HTTR) and helium turbine power conversion and on the technologies whose development have been well under way for IS hydrogen production process so as to minimize cost and risk of deployment. This paper describes the original design features focusing on the plant layout and plant cycle of the GTHTR300C together with present development status of the GTHTR300, IHX, etc. Also, the advantage of the GTHTR300C is presented.

분열형 효모에서 mas3 유전자의 세포내 기능 연구 (Studies on Intracellular Functions of the mas3 Gene in the Fission Yeast, Schizosaccharomyces pombe)

  • 황미라;차재영;신상민;박종군
    • 생명과학회지
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    • 제15권1호
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    • pp.124-131
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    • 2005
  • 세포주기 조절에서 유전자 발현의 조절은 매우 중요한 부분이다. 본 연구에서는 인간의 유전자인 SMARCADl과 상동성을 가지는 분열형 효모의 새로운 유전자 $mas3^+$를 분리하였다. 이 두 유전자는 $87\%$의 상동성을 보인다. $mas3^+$유전자는 DEAD/H box를 포함한 7개의 motif를 가지고 있어서 helicase superfamily 중에서도 SNF2 family에 속한다. kanMX6를 선별 표지로 이용하여 $mas3^+$유전자 결손 세포를 구성하였고 $mas3^+$ 유전자 결손 세포는 UV와 MMS처리 실험에서 정상의 세포와 생존율이 비슷하여 DNA상해회복과는 관련이 없음을 알 수 있었다. $mas3^+$ 유전자의 세포주기별 발현 양을 분석한 결과 $G_2$단계부터 점차적으로 발현양이 늘어났다. $mas3^+$결손 돌연변이를 $26^{\circ}C$$35^{\circ}C$에서 배양한 결과, 비정상적인 세포질 분열 과정으로 인해 다중 격막 세포의 빈도가 증가하였다. 이상의 결과들은 $mas3^+$유전자는 세포질 분열과 세포형태 형성에 연관되어 있음을 시사한다.

Regulation of S100G Expression in the Uterine Endometrium during Early Pregnancy in Pigs

  • Choi, Yo-Han;Seo, Hee-Won;Shim, Jang-Soo;Kim, Min-Goo;Ka, Hak-Hyun
    • Asian-Australasian Journal of Animal Sciences
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    • 제25권1호
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    • pp.44-51
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    • 2012
  • Calcium ions play an important role in the establishment and maintenance of pregnancy, but molecular and cellular regulatory mechanisms of calcium ion action in the uterine endometrium are not fully understood in pigs. Previously, we have shown that calcium regulatory molecules, transient receptor potential vanilloid type 5 (TRPV6) and calbindin-D9k (S100G), are expressed in the uterine endometrium during the estrous cycle and pregnancy in a pregnancy status- and stage-specific manner, and that estrogen of conceptus origin increases endometrial TRPV6 expression. However, regulation of S100G expression in the uterine endometrium and conceptus expression of S100G has been not determined during early pregnancy. Thus, we investigated regulation of S100G expression by estrogen and interleukin-$1{\beta}$ (IL1B) in the uterine endometrium and conceptus expression of S100G during early pregnancy in pigs. We obtained uterine endometrial tissues from day (D) 12 of the estrous cycle and treated with combinations of steroid hormones, estradiol-$17{\beta}$ ($E_2$) and progesterone ($P_4$), and increasing doses of IL1B. Real-time RT-PCR analysis showed that $E_2$ and IL1B increased S100G mRNA levels in the uterine endometrium, and conceptuses expressed S100G mRNA during early pregnancy, as determined by RT-PCR analysis. To determine if endometrial expression of S100G mRNA during the implantation period was affected by the somatic cell nuclear transfer (SCNT) procedure, we compared S100G mRNA levels in the uterine endometrium from gilts with SCNT-derived conceptuses with those from gilts with conceptuses derived from natural mating on D12 of pregnancy. Real-time RT-PCR analysis showed that levels of S100G mRNA in the uterine endometrium from gilts carrying SCNT-derived conceptuses was significantly lower than those from gilts carrying conceptuses derived from natural mating. These results showed that S100G expression in the uterine endometrium was regulated by estrogen and IL1B of conceptus origin, and affected by the SCNT procedure during early pregnancy. These suggest that conceptus signals regulate S100G, an intracellular calcium transport protein, for the establishment of pregnancy in pigs.

Pleurotus eryngii 로부터 항암물질의 분리 (Antitumor Sterol Isolated from the Fruiting Body of Pleurotus eryngii)

  • 이영훈;박기훈;이병원;조용운;최영주;갈상완
    • 생명과학회지
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    • 제16권2호
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    • pp.282-288
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    • 2006
  • 새송이버섯으로부터 활성추적법으로 항암활성이 있는 물질인 에르고스테롤 프록사이드를 분리하였다. 이 스테롤의 구조는 분광법과 NMR법으로 확인하였으며 분자식은 $C_{28}H_{44}O_3$이었다. 폐암과 난소암에 $IC_{50}$값은 각각 $7{\mu}M$$14{\mu}M$이었다. DNA단편화 실험에서 이 화합물은 암세포의 chromosimal DNA 를 사닥다리모양으로 분해하였고, 세포 분열주기의 억제실험에서 G1단계를 억제함을 관찰하였다.