• Title/Summary/Keyword: 인산화반응

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인슐린의 신호전달 기전 : Transcription Factor AP-1 의 역활

  • 김성진
    • Proceedings of the Korean Society of Applied Pharmacology
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    • pp.17-21
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    • 1995
  • 대부분의 인슐린의 작용들은 인슐린 수용체를 통하여 이루어진다. 인슐린이 수용체에 결합하면, 수용체 고유의 tyrosine kinase 효소활성의 증가를 유발시키며, 결과적으로 세포내에 존재하는 기질 단백질, IRS-1, 의 tyrosine 잔기의 인산화를 증가시키게 된다. 이후, 여러 형태의 serine / threonine protein kinase 의 연속적인 활성화가 일어난다. 이들에 부가해서, 인슐린의 효자는 세포핵 내에까지 전달되어 유전자 발현의 조절과 같은 세포핵 고유의 활동에도 관여한다. 현재, 세포막에서 시작된 인슐린의 신호들이 세포핵까지 전달되는 정확한 기전에 대해서는 알려진 바 없지만, 최근의 연구에 의하면 MAP Kinase 와 S6 Kinase 그리고 Transcription Factor AP-1의 중요성이 제시되고 있다. 특히 유전자 조절 기전에는 핵단백질인 transcription factor의 인산화 반응이 큰 역할을 한다고 보고되고 있는바, 본 연구에서 AP-1. transcription factor 의 인산화 반응이 인슐린의 신호전달계에 미치는 역할에 대하여 고찰하였다. 요약하면, AP-1 transcription factor의 구성원인 c-Jun, c-Fos 그리고 Fos 관련 단백질들의 인산화가 인슐린에 의해 증가되며, 동시에 그들의. DNA-binding activity 와 유전자 발현의 활성이 증가됨을 밝힘으로써, AP-1 transcription factor의 인산화 반응이 인슐린의 핵 내에서의 작용기전에 중요한 역할을 함이 제시되고 있다. 또한 AP-1 의 인산화 반응에 관여하는 세포핵 protein kinase로서 Casein Kinase II 의 중요성이 밝혀졌다.

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Effect of $GA_3$ on Ribosomal Protein Phosphorylation in Germinating Zea mays (발아 중인 옥수수에서 리보조옴 단백질의 인산화반응에 미치는 $GA_3$의 효과)

  • 안경섭
    • Journal of Plant Biology
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    • v.33 no.1
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    • pp.59-64
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    • 1990
  • In order to study the effect of GA3 on the phosphorylation of ribosomal proteins during germination in Zea mays, ribosomal proteins were labelled with 32P, extracted, electrophoresed and autoradiographed. There are five phosphorylated ribosomal proteins. One of these is in 40S subunit and has molecular weight of 33,000 daltons. Others are in 60S subunit and have molecular weights of 37,000, 16,000, 15,200 and 13,500, respectively. Phosphorylation of ribosomal proteins was increased maximum 47.7% in shoots of Zea mays treated with GA3.

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Studies on the Mechanisms of Gibberellic Acid Action II. Regulation of Protein Biosynthesis and Phosphorylation by $GA_3$ in the Presence of Actinomycin D (Gibberellic Acid의 작용 기작에 관한 연구 II. Actinomycin D 처리시 $GA_3$에 의한 단백질의 생합성 및 인산화반응의 조절)

  • 심웅섭
    • Journal of Plant Biology
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    • v.25 no.1
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    • pp.3-8
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    • 1982
  • As a part of the studies on the regulatory mechanism of gene expression by gibbrellic acid, the effects of $GA_3$ on the protein biosynthesis and phosphorylation in maize seedlings were investigated in the presence of actinomycin D. The activities of protein biosynthesis and phosphorylation in germinating seeds treated with $GA_3$ were greater than those of the control at the 3-day point after germination. It is assumed that the enhancement of protein biosynthesis by $GA_3$ in the presence of actinomycin D is due to the effects of $GA_3$ on the translational processes in which protein is produced from the mRNA synthesized previously.

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Aqueous Fraction from Korean Red Ginseng Inhibits the Protein Phosphorylation Induced by Tumor Promoter (고려홍삼의 수용성 분획은 종양촉진인자에 의해 유도되는 단백질 인산화반응을 억제한다)

  • Park, Hwa-Jin;Park, Kyeong-Mee;Rhee, Man-Hee;Park, Ki-Hyun
    • Journal of Ginseng Research
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    • v.17 no.2
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    • pp.135-138
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    • 1993
  • Aqueous fractions from Korean red ginseng inhibited the phosphorylations of 40 KD and 20 KD polypeptides which were induced by phorbol-12-myristate-13-acetate (100 nM) in human platelets. Much more carbohydrates were contained in the aqueous fractions than proteins. An aqueous fraction extracted with methanol, mainly, consists of glycoproteins, molecular weights of which were below 18 KD. We may infer that the aqueous fraction from Korean red ginseng do antitumorous and antiplatelet functions.

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Studies on the Mechanisms of Gibberellic Acid Action I. Regulation of Protein Biosynthesis and Phosphorylation by Gibberellic Acid $_{3}$ (gibberellic Acid의 작용기작에 관한 연구 I. $GA_{3}$에 의한 단백질의 생합성 및 인산화반응의 조절)

  • 심웅섭
    • Journal of Plant Biology
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    • v.22 no.4
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    • pp.95-100
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    • 1979
  • As a part of the studies on the regulatory mechanism of gene expression by $GA_{3}$ , the effects of $GA_{3}$ on the protein biosynthesis and phosphorylation in maize seedlings were investigated. 1. The optimum concentration of $GA_{3}$ for the stimulation of the protein biosynthesis was 0.3mM. 2. The protein biosynthesis was remarkably increase by $GA_{3}$ during the germination. The reason for the decrease in the protein biosynthesis by 48hrs. after germination seems to be a staggered gene expression, and/or increases in protease and RNase activities. 3. The ratio of the amount of the newly synthesized protein in germinating seeds treated with $GA_{3}$ to the amount of proteins secreted into the endosperm was similar to that ratio in control. According to this result, it seems that $GA_{3}$ stimulates only the expression of certain definite genes. 4. By the treatment with $GA_{3}$, the rates of biosynthesis and phosphorylation of proteins were increased up to about 1.5 times during germination and 6 times by 72hrs. after germination, respectively. The ratio of the total soluble proteins to the phosphorpoteins considerably increased in the early germination stage (24hrs.) but decreased after 24hrs. According to the above mentioned results, the stimulation of the phosphorylation of proteins of $GA_{3}$ seems to be attributed to the increases in the activities of protein kinases.

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Dehydration of Alcohol Solutions Through Crosslinked Chitosan Composite Membranes II. Dehydration of Ethanol Solution Through Modified Chitosan Composite Membranes (가교키토산 복합막을 통한 알콜수용액의 탈수 II. 변성 키토산 복합막을 통한 에탄올의 탈수)

  • 이영무;남상용;유제강;류경옥
    • Membrane Journal
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    • v.6 no.4
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    • pp.242-249
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    • 1996
  • To improve pervaporation performance of water/ethanol mixtures, chitosan/poly(vinyl alcohol) blended and phosphorylated chitosan composite membranes were prepared. Chitosan/poly(vinyl alcohol) blends were prepared with various blend ratios and then crosslinked with glutaraldehyde by two methods. With increasing crosslinking agent content and crosslinking times separation factor increased and permeate flux decreased. Separation factor of the membrane which contains glutaraldehyde as a crosslinking agent was higher than that of the membrane surface crosslinked. Phosphorylated chitosan was prepared with various reaction times and composite membrane was prepared. As reaction times increased, the separation factor increased with high affinity for water.

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ETABr 용액내에서 p-Nitrophenyldiphenylphosphinate의 탈인산화반응에 미치는 Benzimidazole의 촉매효과

  • Kim, Jeong-Bae
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • pp.469-472
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    • 2006
  • BI 및 ETABr의 농도변화에 따른 속도상수의 변화는 이 반응이 단순한 1차 및 2차 반응 속도식에 맞지 않는다. 이와 같은 현상은 용액 속에서 두 반응 시약인 p-NPDPIN 및 BI와 상전이촉매인 ETABr 사이에 많은 수의 작은 응집된 입자(aggregates)을 형성함을 의미한다. 수용액 속에서는 불용성인 p-NPDPIN과 수용성인 BI가 충돌하여 반응할 기회가 적은데 반하여 ETABr은 이 두 시약을 함께 수용하여 세 분자 사이에 응집현상이 일어남으로 p-NPDPIN과 BI가 반응하기에 충분한 거리 내에 있게 된다. 바꾸어 말하면, 이 두 반응물질이 1:1 adducts로 반응하기보다는 여러 ETABr과 함께 많은 수의 반응분자들이 회합(응집) 되어 있음을 뜻한다.

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Biochemical Study on Soft-rotted Sweetpotatoes (연부(軟腐)고구마의 생화학적(生化學的) 연구(硏究))

  • Chun, Jae-Kun
    • Applied Biological Chemistry
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    • v.10
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    • pp.47-61
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    • 1968
  • Sweetpotato infected by Soft-rot, Rhizopus nigricans, has been investigated for its biochemical changes. The results of the present experiment are summarized as follows: 1. From the Soft-rotted tuber, nineteen Ehrlich's positive substances and three fluorescent compounds which had not been found in a healthy tuber were detected with thin layer chromatography. 2, Ipomeamarone and umbelliferone, each of which are predominating substances among the Ehrlich's positive and fluorescent compounds, were isolated by silica gel column chromatography and studied for their identities. 3. Time course biosynthesis of the metabolites was studied and discussed for their possible biosynthetic pathways. 4. Among the metabolites, ipomeamarone and ipomeamarone-like substances have enzyme: inhibitive action against ${\alpha}$-amylase and probably other enzymes; the inhibition type was determined as the uncompetitive one. 5. Ipomeamarone obtained from soft-rotted sweetpotato was proved to have an uncoupling action as 2, 4-dinitrophenol.

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Inhibition of Oligomycin Biosynthesis by olmA5 Gene Knock-out in Streptomyces avermitilis (Streptomyces avermitilis에서 olmA5 Gene의 Knock-out에 의한 Oligomycin 합성 억제)

  • Kang, Hyun-Woo;Ryu, Yeon-Woo
    • KSBB Journal
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    • v.24 no.3
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    • pp.279-286
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    • 2009
  • Streptomyces is well known for their ability to synthesize enormous varieties of antibiotics as secondary metabolites. Among them, S. avermitilis produces avermectins, a group of antiparasitic agents used in human and veterinary medicine. However, S. avermitilis also produces oligomycin, which is a potential toxic inhibitor of oxidative phosphorylation in mammalian cells. Therefore, we decided to disrupt oligomycin synthetase gene to prevent co-production of oligomycin in S. avermitilis. To create plasmid for disruption, the smallest gene of oligomycin synthetase gene cluster was obtained by PCR from S. avermitilis chromosome. Then, apramycin resistance gene was inserted in oligomycin synthetase gene for selection. After transformation of this plasmid, oligomycin synthetase gene (olmA5) in the chromosome was displaced with disruption cassette on the plasmid via homologous recombination. As a result of this gene replacement, we obtained mutants (olmA5::apra) that no longer makes the toxic oligomycin. And the mutants confirmed by PCR and HPLC analysis. However, showed no increasement of avermectin production in the mutant was observed.

Comparison of Physicochemical Properties of Starch Phosphates Prepared by Dry Heating and Extrusion Process (건식법과 Extrusion 공정에 의해 제조한 인산전분의 이화학적 성질 비교)

  • Kim, Chong-Tai;Ryu, Gi-Hyung;Kim, Dong-Chul;Kim, Chul-Jin
    • Korean Journal of Food Science and Technology
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    • v.22 no.6
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    • pp.651-658
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    • 1990
  • Starch phosphates were prepared by dry heating, gelatinizing method and extrusion process using sodium tripolyphosphote (STPP) as a substitution reagent and their physicochemical properities were compared. In the preparation of starch phosphate by dry heating method(DSP), the effect of reaction temperature was the most significant to the DS(Degree of substitution). In the phosphorylation reaction with gelatinized starch(GSP), the substitution ratio was increased with increasing the reaction temperature, but the increase was insignificant above $85^{\circ}C$. By extrusion with the corn starch containing 2.0% STPP at various moisture contents of 20, 25 and 30%, the DS values of extrudate(WESP) were within the range of between 0.0066 and 0.0083. The starch phosphate(DSP) products showed lowering the gelatinization temperature, increasing the clarity of the starch paste. However, WESP showed higher gelatinization temperature than that of raw starch. The starch phosphate prepared by extrusion process showed lower apparent viscosity of paste than that of the DSP at same condition. All of starch phosphates showed reducing the tendency of the paste retrogradation.

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