• 제목/요약/키워드: RAB

검색결과 74건 처리시간 0.028초

$Ca^{2+}$ CALMODULIN CAUSES RAB3A TO DISSOCIATE FROM SYNAPTOSOMAL MEMBRANES

  • Park, Jae-Bong;Christoper C. Farnsworth;John A. Glomset
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 1996년도 정기총회 및 학술발표회
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    • pp.38-38
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    • 1996
  • Rab3A is a synaptic vesicle-associated, GTP-binding protein that has been implicated in the regulation of neurotransmission. We show here that Ca2+/calmodulin can form a 1:1 complex with Rab3A and cause it to dissociate from synaptosomal membranes. Formation of the complex requires both the lipidated C-terminus of Rab3A and the presence of guanine nucleotide. (omitted)

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우슬 추출물이 골아세포 증식과 분화에 미치는 효과 (Effects of Radix Achyranthis Bidentatae Extract on Proliferation and Differentiation in Human Osteoblast-like Cells)

  • 서은아;문형철
    • 동의생리병리학회지
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    • 제18권6호
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    • pp.1821-1824
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    • 2004
  • In order to investigate the effects of Radix Achyranthis Bidentatae (RAB) on the growth and differentiation of human osteoblast-like cells, we supplemented the culture medium of MG-63 cells with various concentrations of RAB water extracts. RAB extracts significantly stimulated cell growth, as confirmed by the colorimetric MTT (3-dimethylthiazol-2,5-diphenyltetrazolium bromide) assay. RAB extracts also increased the alkaline phosphatase (ALP) activity, which is a osteoblast differentiation marker. These results suggest that RAB can stimulate osteoblastic activity and may represent new pharmacological tools for the treatment of osteoporosis.

Mar (Multiple-Antibiotic-Resistance) Operon 돌연변이 대장균의 그람음성 세균들간 전파 가능성에 대한 근거 (Evidences that Suggest the Spread of Multiple-Antibiotic-Resistance (mar) Operon of Escherichia coli Mutants among Gram-Negative Bacilli)

  • Byung-Tae Park
    • 대한의생명과학회지
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    • 제5권1호
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    • pp.17-26
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    • 1999
  • Mar (multiple-antibiotic-resistance) 대장균의 marRAB 돌연변이가 그람음성 세균들 사이로 전파 될수 있는지를 알아보기 위해서, 염색체 위의 marRAB 돌연변이를 $\lambda$placMu9 (Km$^{r}$)를 이용하여 대장균의 다른 균주내의 pUC19 (Lac$^{+}$, Ap$^{r}$)의 클로닝 사이트, S. typhimurium 및 P. aeruginosa의 염색체 위로 각각 전달시킨 후, Mar phenotype, Km$^{r}$, Lac$^{-}$, 혹은 Ap$^{r}$ 균주를 선택한 다음, salicylate (SAL)의 유도 (induction) 유무에 따른 항생제 내성검사를 실시하였다. pUC19의 보유 유무에 관계없이 대조군인 야생형 대장균 JM109, NM522에 비해서, pUC19::marRAB 돌연변이를 가진 JM109 혹은 NM522의 대부분 균주들은 항생제 내성 수준들이 훨씬 더 높았으며, Mar표현형의 유도도 SAL에 의해서 훨씬 더 높게 나타났다. 하지만 일부 소수의 항생제에 대해서는 예외적으로 내성 수준이 더 낮게 나타났는데, 야생형 JM109 균주에서는 chloramphenicol (Cm)과 tetracycline (Tc)이 , pUC19::marRAB 돌연변이를 가진 NM522 균주 에서는 Tc와 ciprofloxacin (Cp)에 대한 내성 수준이 각각 더 낮게 나타났다. S. typhimurium 및 P. aeruginosa에 대한 같은 실험의 결과도 야생형 대장균의 경우와 거의 대부분 일치하였다. 형질전환 (transformation)과 형질도입 (transduction)의 방법을 주로 사용한 이 실험의 결과는, marRAB 돌연변이가 그람음성 세균들 사이로 전파될 수 있음을 간접적으로 암시한다.

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Affinity between TBC1D4 (AS160) phosphotyrosine-binding domain and insulin-regulated aminopeptidase cytoplasmic domain measured by isothermal titration calorimetry

  • Park, Sang-Youn;Kim, Keon-Young;Kim, Sun-Min;Yu, Young-Seok
    • BMB Reports
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    • 제45권6호
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    • pp.360-364
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    • 2012
  • Uptake of circulating glucose into the cells happens via the insulin-mediated signalling pathway, which translocates the glucose transporter 4 (GLUT4) vesicles from the intracellular compartment to the plasma membrane. Rab GTPases are involved in this vesicle trafficking, where Rab GTPases-activating proteins (RabGAP) enhance the GTP to GDP hydrolysis. TBC1D4 (AS160) and TBC1D1 are functional RabGAPs in the adipocytes and the skeletonal myocytes, respectively. These proteins contain two phosphotyrosine-binding domains (PTBs) at the amino-terminus of the catalytic RabGAP domain. The second PTB has been shown to interact with the cytoplasmic region of the insulin-regulated aminopeptidase (IRAP) of the GLUT4 vesicle. In this study, we quantitatively measured the ${\sim}{\mu}M$ affinity ($K_D$) between TBC1D4 PTB and IRAP using isothermal titration calorimetry, and further showed that IRAP residues 1-49 are the major region mediating this interaction. We also demonstrated that the IRAP residues 1-15 are necessary but not sufficient for the PTB interaction.

Icariin의 멜라닌합성 촉진 작용 (Icariin promotes melanin synthesis)

  • 차수빈;박설아;강리아민주;우원홍;문연자
    • 대한한의학방제학회지
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    • 제28권1호
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    • pp.81-90
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    • 2020
  • Objectives : This study was conducted to investigate the effects of major constituents of Epimedium koreanum Nakai (Icariin, epimedium A, epimedium B, and epimedium C) on melanin synthesis. Methods : We measured melanin contents, tyrosinase activity, and expression of Rab27a in B16F10 cells cultured with Epimedium koreanum Nakai ethanol extract (EKN) and their major constituents. After treatment with H89 and dibutyryl cAMP, which inhibit or promote the activation of PKA, we observed changes in melanin synthesis and tyrosinase activity stimulated by EKN. Results : Among them, EKN and icariin enhanced tyrosinase activity and melanin contents. We confirmed that EKN augmented melanin synthesis via cAMP/PKA pathway. Icariin-induced tyrosinase activity and melanin content were attenuated by PKA inhibitor H89, while melanogenic effect of icariin was further augmented by cAMP analog, dbc AMP. However, icariin did not affect the expression of small GTPase Rab27a involved in melanosome transport. Conclusions : These results suggest that icariin promotes melanogenesis through cAMP/PKA pathway but does not affect small GTPase Rab27a.

A Comparison of Shortening and Shortening Speed in Sartorius, Gastrocnemius and Rectus Abdominis Muscles of Uromastix hardwickii

  • Fehmeena, S.;Azeem, M. Abdul
    • The Korean Journal of Physiology
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    • 제28권1호
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    • pp.61-70
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    • 1994
  • A new method is used to record the actual shortening produced during the auxotonic activity of the sartorius (SAR), gastrocnemius (CAS) and rectus abdominis (RAB) muscles of a lizard Uromastix. The auxotonic twitch and tetanus records thus obtained were used for the first time to calculate the coefficient of linear shortening (COLS). This coefficient represent the relative Index between change in length $(\Delta\;L=L_0-L_1)$ and tension $({\Delta}P\;P_0-P_1)$ due to shortening at the steepest rising phase of the twitch and tetanus, recorded at resting length. In addition to this, maximum shortening $(S_{max})$ and auxotonic tensions were also determined at resting lengths of these muscles. The COLS was found to express the speed of shortening and auxotonic tensions are suggested to be of value to express the internal architecture of SAR, GAS & RAB muscles. The results are discussed in terms of contractile and elastic elements of the muscles alongwith the importance of shortening at resting lengths in skeletal muscles.

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AMI 사업에 민간투자를 유인하기 위한 우크라이나 배전서비스 요금정책 연구 (A Study on the Electricity Distribution Tariff Regulation of Ukraine to Encourage Private Investment on the AMI)

  • 김철년
    • 한국융합학회논문지
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    • 제12권11호
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    • pp.19-26
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    • 2021
  • 본 연구는 우크라이나 에너지효율화 분야 민간투자 활성화를 위한 배전서비스 요금정책의 제안을 목적으로 하였다. 우크라이나는 전력분야 시장 개편과 에너지효율화를 유도하기 위한 정책 도입으로 해당 분야 경쟁력이 높은 국내 기업들이 진출하기에 최적기로 정책과 시장에 대한 사전 연구가 필요하다. 우크라이나 32개 배전회사 중 한 곳을 선정하고 에너지효율화의 핵심인 AMI 도입을 민간투자로 진행할 경우를 가정하여 투자 경제성분석 시뮬레이션을 진행하여 배전서비스 요금정책 중 핵심적인 RAB 정책의 주요 내용의 방향을 도출하였다. 배전회사가 민간사업자로부터 도입하는 AMI 리스 자산에 대해 규제자산으로 인정이 필요하며, 기타 정책은 현재의 규정대로 적용되어도 투자 결정에는 크게 영향을 주지 않았다. 시뮬레이션을 통해 데이터를 제시함으로써 실무적 근거를 제공한 것에 연구의 의의가 있으며, 에너지효율화 분야들로 연구가 확장되면 기업들의 해외진출에 도움이 될 것으로 기대된다.

Hesperidin Suppresses Melanosome Transport by Blocking the Interaction of Rab27A-Melanophilin

  • Kim, Bora;Lee, Jee-Young;Lee, Ha-Yeon;Nam, Ky-Youb;Park, JongIl;Lee, Su Min;Kim, Jin Eun;Lee, Joo Dong;Hwang, Jae Sung
    • Biomolecules & Therapeutics
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    • 제21권5호
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    • pp.343-348
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    • 2013
  • We investigated the inhibitory effects of hesperidin on melanogenesis. To find melanosome transport inhibitor from natural products, we collected the structural information of natural products from Korea Food and Drug Administration (KFDA) and performed pharmacophore-based in silico screening for Rab27A and melanophilin (MLPH). Hesperidin did not inhibit melanin production in B16F10 murine melanoma cells stimulated with ${\alpha}$-melanocyte stimulating hormone (${\alpha}$-MSH), and also did not affect the catalytic activity of tyrosinase. But, hesperidin inhibited melanosome transport in melanocyte and showed skin lightening effect in pigmented reconstructed epidermis model. Therefore, we suggest that hesperidin is a useful inhibitor of melanosome transport and it might be applied to whitening agent.