• Clinical and Experimental Reproductive Medicine
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• 제13권2호
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• pp.201-206
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• 1986

These experiments were conducted to know whether RNA syntheis is involved in the cumulus expansion and oocyte maturation of mouse cumulus-oocyte complexes in vitro. Mouse cumulus-oocyte complexes(COC's) were cultured in the presence of cordycepin, an inhibitior of RNA synthesis and its effect on the cumulus expansion and oocyte maturation were examined. The results were as follows. 1. Continuous presence of cordycepin in the medium(200${\mu}g/ml$) inhibited the HCG-induced cumulus cell expansion of mouse complexes. This inhibition was reversible. 2. When the COC'S were preincubated with different concentration of cordycepin plus HCG for 3 hours and then transferred to the plain medium, the HCG induced cumulus expansion was suppressed at $100{\mu}g/ml$ of cordycepin. 3. When the COC'S were cultured with cordycepin after HCG stimulation(3hrs), the cumulus expansion were not suppressed by cordycepin. 4. Oocyte meiotic maturation did not appear to be affected by cordycepin. The data presented here imply that RNA synthesis is involved in the cumulus expansion process and that mouse oocytes are more resistant to RNA synthesis inhibitor than cumulus cells.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2004년도 국제학술심포지움
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• pp.22-26
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• 2004

A self-replicating RNA ligase ribozyme was converted to a cross-catalytic format whereby two ribozymes direct each other's synthesis from a total of four component substrates. Each ribozyme binds two RNA substrates and catalyzes their ligation to form the opposing ribozyme. The two ribozymes are not perfectly complementary, as is the case for replicating nucleic acid genomes in biology. Rather, the ribozymes contain both template elements, which are complementary, and catalytic elements, which are identical. The specificity of the template interactions allows the cross-catalytic pathway to dominate over all other reaction pathways. In the presence of $2{\mu}M$ each of the corresponding substrates, one ribozyme catalyzes the synthesis of the second ribozyme with an initial rate of $6.8{\times}10^{-3}\;min^{-1}$, while the second ribozyme catalyzes the synthesis of the first with an initial rate of $2.9{\times}10^{-3}min{-1}$. As the concentration of the two ribozymes increases, the rate of formation of additional ribozyme molecules increases, consistent with the overall autocatalytic behavior of the reaction system. Here, I present results that possibly demonstrate a clue for a self-replicating molecule by showing an RNA ligase ribozyme, which is reminiscent of 'Prebiotic Era'.

• 대한수의학회지
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• 제26권1호
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• pp.31-37
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• 1986

The present study has been carried out to elucidate the antiestrogenic effects of tamoxifen on RNA and protein synthesis in uteri of immature rats. Immature female Sprague-Dawley rats were allocated into 4 groups and injected with $5{\mu}g$ of estradiol-$17{\beta}$, $50{\mu}g$ of tamoxifen, a combination of both, or vehicle only subcutaneously three times with an interval of 24 hours respectively. The specific activities of $^3H$-uridine incorporation into uterine RNA and those of $^3H$-leucine incorporation into uterine protein were measured before and 1, 3, 6, 12, 24, 48 and 72 hours after the above treatments. The results obtained were summarized as follows; 1. Tamoxifen itself increased RNA synthesis an hour after treatment(169.18% of control), but it's specific activity was reduced to control level after 3 hours. Tamoxifen inhibited significantly (p<0.01) the activity of RNA synthesis of estradiol-$17{\beta}$. 2. The increasing rate of protein synthesis was lower in tamoxifen treated group than that in estradiol-$17{\beta}$ treated group. While the rate was steadily increased up to 357.4% of control by estradiol-$17{\beta}$ in 72 hours, tamoxifen itself failed to increase the rate after 24 hours and significantly (p<0.01) inhibited the activity of estradiol-$17{\beta}$(-167.4%).

• 한국작물학회지
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• 제37권5호
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• pp.397-404
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• 1992

본 연구는 내염성이 비교적 강한 Japonica형 품종인 섬진벼와 내염성이 비교적 약한 통일형 품종인 칠성벼를 염분농도에 따른 세포주기를 측정하고 각 phase의 기간 변화도 조사하였으며, 또한 DNA, RNA 및 단백질 합성량를 제출하여 세포주기와 어떠한 관련성이 있는지를 조사한 결과 다음과 같다. 1. 섬진벼와 칠성벼의 세포주기는 염분농도 0%, 0.3% 및 0.6%에 서 12시간으로 동일하였다. 2. 세포주기로부터 측정된 각 phase 별 기간은 무처리구와 처리구에서 차이를 보였다. 섬진벼가 무처리구에서 G1=3.3, S=3.8, G2=2.8, 그리고 M=2.1 시간이었고, 0.3%에서 G1=3.5, S=3.6, G2=2.8, 그리고 M=2.1 시간이었으며, 0,6%에서 G1=3.5, S=3.6, G2=2.8, 그리고 M=2.1 시간으로 무처리구에 비하여 G1 기간은 길어겼고, S 기간은 약간 짧아졌다. 칠성벼에서는 무처리구에서 G1=2.6, S=5.2, G2=2.3, 그리고 M=1.9 시간이었고, 0.3%에서 G1=2.5, S=6.2, G2=1.6 그리고 M=1.7 시간이었으며, 0.6%에서 G1=2.1, S=6.0, G2=2.0 그리고 M=1.9 시간으로 무처리구에 비하여 처리구의 G1과 G2 기간은 짧아졌고 S 기간은 길어졌으며, 이는 섬진벼의 변화와 반대 성향을 보여 주었다. 3. 섬진벼에서 처리구가 무처리구에 비하여 DNA와 RNA 합성은 감소한 반면, 단백질 합성은 증가하였으며, 칠성벼에서는 처리구가 무처리구에 비하여 DNA와 단백질 합성은 증가하였으나, RNA 합성은 섬진벼와 같이 감소하였다.

• BMB Reports
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• 제50권4호
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• pp.186-193
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• 2017

In mammals, cap-dependent translation of mRNAs is initiated by two distinct mechanisms: cap-binding complex (CBC; a heterodimer of CBP80 and 20)-dependent translation (CT) and eIF4E-dependent translation (ET). Both translation initiation mechanisms share common features in driving cap- dependent translation; nevertheless, they can be distinguished from each other based on their molecular features and biological roles. CT is largely associated with mRNA surveillance such as nonsense-mediated mRNA decay (NMD), whereas ET is predominantly involved in the bulk of protein synthesis. However, several recent studies have demonstrated that CT and ET have similar roles in protein synthesis and mRNA surveillance. In a subset of mRNAs, CT preferentially drives the cap-dependent translation, as ET does, and ET is responsible for mRNA surveillance, as CT does. In this review, we summarize and compare the molecular features of CT and ET with a focus on the emerging roles of CT in translation.

• BMB Reports
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• 제48권3호
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• pp.139-146
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• 2015

Adaptive brain function and synaptic plasticity rely on dynamic regulation of local proteome. One way for the neuron to introduce new proteins to the axon terminal is to transport those from the cell body, which had long been thought as the only source of axonal proteins. Another way, which is the topic of this review, is synthesizing proteins on site by local mRNA translation. Recent evidence indicates that the axon stores a reservoir of translationally silent mRNAs and regulates their expression solely by translational control. Different stimuli to axons, such as guidance cues, growth factors, and nerve injury, promote translation of selective mRNAs, a process required for the axon's ability to respond to these cues. One of the critical questions in the field of axonal protein synthesis is how mRNA-specific local translation is regulated by extracellular cues. Here, we review current experimental techniques that can be used to answer this question. Furthermore, we discuss how new technologies can help us understand what biological processes are regulated by axonal protein synthesis in vivo.

• Journal of Plant Biology
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• 제34권2호
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• pp.159-163
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• 1991

합성 식물생장조절제인 dimethipin의 작용기작을 밝히고자 보리 무배부 종자 시스템에서 gibberellic acid(GA3)에 의해 유도되는 ${\alpha}-amylase$ 활성에 미치는 dimethipin의 영향을 조사하였다. Dimethipin은 mRNA와 단백질 함량 및 GA3에 의해 유도되는 ${\alpha}-amylase$ 활성을 뚜렷하게 억제하였다. 그러나 억제효과는 GA3 처리 후 dimethipin 첨가시간 간격이 커질수록 점점 감소하였다. Dimethipin을 GA3 처리후 18시간 이내에 첨가하였을 때 mRNA 함량증가를 억제하였다: 그러나 GA3 처리 18시간 경과 후에 첨가하였을 경우에도 수용성 단백질 함량 및 ${\alpha}-amylase$ 활성 증가를 억제하였다. 이러한 결과로 미루어보아 dimethipin은 mRNA 합성과 ${\alpha}-amylase$ 단백질 합성을 공히 억제하는 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권1호
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• pp.133-140
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• 2005

Although amino acids are substrates for the synthesis of proteins and nitrogen-containing compounds, it has become more and more clear over the years that these nutrients are also extremely important as regulators of body protein turnover. The branched-chain amino acids (BCAAs) together or simply leucine alone stimulate protein synthesis and inhibit protein breakdown in skeletal muscle. However, it was only recently that the mechanism(s) involved in the regulation of protein turnover by BCAAs has begun to be defined. The acceleration of protein synthesis by these amino acids seems to occur at the level of peptide chain initiation. Oral administration of leucine to food-deprived rats enhances muscle protein synthesis, in part, through activation of the mRNA binding step of translation initiation. Despite our knowledge of the induction of protein synthesis by BCAAs, there are few studies on the suppression of protein degradation. The recent findings that oral administration of leucine rapidly reduced $N^{\tau}$-methylhistidine (3-methylhistidine; MeHis) release from isolated muscle, an index of myofibrillar protein degradation, indicate that leucine suppresses myofiblilar protein degradation. The details of the molecular mechanism by which leucine inhibits proteolysis is just beginning to be elucidated. The purpose of this report was to review the current understanding of how BCAAs act as regulators of protein turnover.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.804-819
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• 2003

It has been known that adenine is a very important material in living cells. Because, adenine is a member of nucleotide base, so it takes part in DNA, RNA and ATP synthesis. There are many reports that adenine participated in ingredients, especially DNA, RNA, NADH and ATP, affect on the cell. As well adenosine, conjugated adenine to glycoside, was known to anti-wrinkle compound. But there is no report whether adenine shows a good effect on the skin, especially anti-wrinkle. So, in this study, we tested whether adenine affects cell proliferation, collagen synthesis, collagenase synthesis inhibition in human dermal fibroblasts. In addition, we performed clinical study with adenine cream. Cell proliferation effect was tested by MTT assay. Collagen and collagenase synthesis were measured by Immunoassay with ELISA kit. Clinical study was performed by IECK according to KFDA Functional Cosmetic method. The results of cell proliferation show that 10$^{-6}$ ~10$^{-8}$ ％ of adenine increases cell proliferation about 50 ％ compare with non-treated control. At 10$^{-7}$ ~10$^{-10}$ ％, adenine increases type I collagen synthesis about 50％, decreases type I collagenase about 22％ compare with non-treated control. The results of clinical study show that 0.05％ adenine treated group reduces wrinkle significantly compare with placebo treated group. Therefore adenine may be a new anti-wrinkle candidate, through increases cell proliferation and collagen synthesis dramatically. And it decreases collagenase synthesis. So adenine could be used as a new anti-wrinkle agent.

• Asian-Australasian Journal of Animal Sciences
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• 제6권3호
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• pp.339-342
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• 1993

This influence of dietary medium chain triglyceride on liver protein synthesis in chicks was investigated using a large dose injection of $L-[4-^3H]$ phenylalanine. Dietary medium chain triglyceride increased liver weight and liver fat content of chicks compared to the long chain triglyceride group. Fractional synthesis rate of liver protein was increased by dietary medium chain triglyceride, which was accounted for not by elevating protein synthesized per unit RNA but by enhancing RNA: protein ratio.