• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2000년도 국제심포지움
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• pp.3-4
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• 2000

The synthesis of acyl-CoA catalyzed by acyl-CoA synthetase (ACS, EC 6.2.1.3) from fatty acid, ATP, and CoA is a crucial reaction in mammalian fatty acid metabolism. In arachidonate metabolism, acyl-CoA synthetase(ACS) plays a key role in the esterification of free arachidonate into membrane phospholipids. Following its release by the action of calcium dependent phospholipase, free arachidonate is believed to be rapidly converted to arachidonoyl-CoA and reesterified into phospholipids in order to prevent excessive synthesis of eicosanoids. In previous studies, we have characterized five ACSs (designated as ACS1-5) with different tissue distribution. ACS1, ACS2, and ACS5 are similar in structure and fatty acid preference, and completely different from ACS3 and ACS4. The latter are arachidonate-preferring enzymes closely related in structure but expressed in different tissues: ACS3 mRNA is highly expressed in the brain and the mRNA for ACS4 is expressed in steroidogenic tissues including adrenal gland, ovary, and testis. To learn more about the potential function of ACS4 in arachidonate metabolism, we have produced knock-out mice for ACS4 gene. ACS4+/- females become pregnant less frequently and produce small litters with extremely low transmission of the disrupted alleles. Striking morphological changes including extremely enlarged uterine filled with numerous proliferative cysts of various size were detected in ACS4+/- females. Furthermore, marked accumulation of prostaglandins were seen in the uterus of heterozygous females. These results indicate that ACS4 is critical for the uterine arachidonate metabolism and heterozygous disruption of its gene lead to impaired pregnancy.

• Carbon letters
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• 제10권3호
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• pp.181-189
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• 2009

Activated carbon spheres (ACS) were prepared at different heating rates by carbonization of the resole-type phenolic beads (PB) at $950^{\circ}C$ in $N_2$ atmosphere followed by activation of the resultant char at different temperatures for 5 h in $CO_2$ atmosphere. Influence of heating rate on porosity and temperature on carbon structure and porosity of ACS were investigated. Effect of heating rate and temperature on porosity of ACS was also studied from adsorption isotherms of nitrogen at 77 K using BET method. The results revealed that ACS have exhibited a BET surface area and pore volume greater than $2260\;m^2/g$ and $1.63\;cm^3/g$ respectively. The structural characteristics variation of ACS with different temperature was studied using Raman spectroscopy. The results exhibited that amount of disorganized carbon affects both the pore structure and adsorption properties of ACS. ACS were also evaluated for structural information using Fourier Transform Infrared (FTIR) Spectroscopy. ACS were evaluated for chemical composition using CHNS analysis. The ACS prepared different temperatures became more carbonaceous material compared to carbonized material. ACS have possessed well-developed pores structure which were verified by Scanning Electron Microscopy (SEM). SEM micrographs also exhibited that ACS have possessed well-developed micro- and meso-pores structure and the pore size of ACS increased with increasing activation temperature.

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2001년도 제2차 연수강좌
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• pp.213-216
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• 2001

본 연구에 의해 Arachidonoyl-CoA synthetase (ACS4)에 관하여 이하의 것을 증명하였다. 1. Moues ACS4 cDNA와 단백질을 분석한 결과 뇌에 특이적으로 발현하는 새로운 78 kDa의 ACS4 분자종을 발견하였다. 2. Steroid 생산세포에서 ACS4는 cAMP와 AA에 의해 유도되는 것을 증명하였다. 3. ACS4의 결손은 웅성 반성접합체에서 외견, 성장, 행동, 생식에 영향을 주지 않지만, 자성 이형접합체에서는 자궁내막의 비후와 낭포 (cyst)를 발생시켜 자궁기능을 저하시키는 것을 입증하였다. 4. ACS4는 자궁내막의 발생과 황체의 퇴화과정에서 중요한 역할을 담당하는 것으로 사료된다.

• Journal of Plant Biotechnology
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• 제2권2호
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• pp.61-71
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• 2000

By screening a cDNA library of auxin-treated mung bean (Vigna radiata L.) hypocotyls, we have isolated two full-length cDNA clones, pVR-ACS6 and pVR-ACS7, for 1-aminocyclopropane-1-carboxylate (ACC) synthase, the rate-limiting enzyme in the ethylene biosynthetic pathway. While PVR-ACS6 corresponds to the previously identified PCR fragment pMBA1, pVR-ACS7 is a new cDNA clone. A comparison of deduced amino acid sequences among auxin-induced ACC synthases reveal that these enzymes share a high degree of homology (65-75%) to VR-ACS6 and VR-ACS7 polypeptides, but only about 50% to VR-ACS1 polypeptide. ACS6 and ACS7 are specifically induced by auxin, while ACS1 is induced by cycloheximide, and to lesser extent by excision and auxin treatment. Results from nuclear run-on transcription assay and RNA gel blot studies revealed that all three genes were transcriptionally active displaying unique patterns of induction by IAA and various hormones in etiolated hypocotyls. Particularly, 24-epibrassinolide (BR), an active brassinosteroid, specifically enhanced the expression of VR-ACS7 by distinct temporal induction mechanism compared to that of IAA. In addition, BR synergistically increased the IAA-induced VR-ACS6 and VR-ACS7 transcript levels, while it effectively abolished both the IAA- and kinetin-induced accumulation of VR-ACS1 mRNA. In light-grown plants, VR-ACS1 was induced by IAA in roots, whereas W-ACS6 in epicotyls. IAA- and BR-treatments were not able to increase the VR-ACS7 transcript in the light-grown tissues. These results indicate that the expression of ACC synthase multigene family is regulated by complex hormonal and developmental networks in a gene- and tissue-specific manner in mung bean plants. The VR-ACS7 gene was isolated, and chimeric fusion between the 2.4 kb 5'-upstream region and the $\beta$-glucuronidase (GUS) reporter gene was constructed and introduced into Nicotiana tobacum. Analysis of transgenic tobacco plants revealed the VR-ACS7 promoter-driven GUS activity at a highly localized region of the hypocotyl-root junction of control seedlings, while a marked induction of GUS activity was detected only in the hypocotyl region of the IAA-treated transgenic seedlings where rapid cell elongation occurs. Although there was a modest synergistic effect of BR on the IAA-induced GUS activity, BR alone failed to increase the GUS activity, suggesting that induction of VR-ACS7 occurs via separate signaling pathways in response to IAA and BR.

• Molecules and Cells
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• 제38권7호
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• pp.597-603
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• 2015

Biosynthesis of the phytohormone ethylene is under tight regulation to satisfy the need for appropriate levels of ethylene in plants in response to exogenous and endogenous stimuli. The enzyme 1-aminocyclopropane-1-carboxylic acid synthase (ACS), which catalyzes the rate-limiting step of ethylene biosynthesis, plays a central role to regulate ethylene production through changes in ACS gene expression levels and the activity of the enzyme. Together with molecular genetic studies suggesting the roles of post-translational modification of the ACS, newly emerging evidence strongly suggests that the regulation of ACS protein stability is an alternative mechanism that controls ethylene production, in addition to the transcriptional regulation of ACS genes. In this review, recent new insight into the regulation of ACS protein turnover is highlighted, with a special focus on the roles of phosphorylation, ubiquitination, and novel components that regulate the turnover of ACS proteins. The prospect of cross-talk between ethylene biosynthesis and other signaling pathways to control turnover of the ACS protein is also considered.

• 대한전자공학회논문지SD
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• 제42권1호
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• pp.69-77
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• 2005

비터비 디코더는 통신 시스템에서 가장 핵심적인 부분 중의 하나로써 순방향 오류 정정을 위해 사용된다. 통신 속도의 고속화가 진행됨에 따라 고속에서 동작할 수 있는 통신 모듈의 개발이 점차 중요해지고 있다. 비터비 디코더는 궤환구조를 갖는 ACS 연산의 특성상 고속화가 매우 어렵다. 본 논문에서는 비터비 디코더의 고속화와 면적을 모두 고려한 효율적인 radix-4 ACS 구조를 제안하였다. 비터비 디코더의 ACS 연산을 재 정렬하여 면적을 절약하였고 경로 메트릭 메모리를 retiming하여 디코더의 속도를 개선하였다. 제안된 ACS 구조는 VHDL로 구현되었고 Xilinx의 ISE 6.2i에서 합성되었다. 실험을 통해서 제안된 구조의 AT product가 기존의 고속 radix-4 ACS 구조보다 11% 개선된 것을 확인할 수 있었다.

• BMB Reports
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• 제40권5호
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• pp.791-800
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• 2007

Ethylene performs an important function in plant growth and development. 1-aminocyclopropane-1-carboxylate (ACC) synthase (ACS), the key enzyme involved in ethylene biosynthesis, has been the focus of most ethylene studies. Here, a cotton ACS gene referred to as Gossypium hirsutum ACS1 (GhACS1), was isolated. The full-length cDNA of GhACS1 encodes for a 476-amino acid protein which harbors seven conserved regions, 11 invariant amino acid residues, and the PLP binding active site, all of which characterize ACC synthases. Alignment analysis showed that GhACS1 shared a high degree of identity with other known ACC synthases from different species. Two introns were detected in the genomic DNA sequence, and the results of Southern blot analysis suggested that there might be a multi-gene family encoding for ACC synthase in cotton. From the phylogenetic tree constructed with 24 different kinds of ACC synthases, we determined that GhACS1 falls into group II, and was closely associated with the wound-inducible ACS of citrus. The analysis of the 5' flanking region of GhACS1 revealed a group of putative cis-acting elements. The results of expression analysis showed that GhACS1 displayed its transient expression nature after wounding, abscisic acid (ABA), and $CuCl_2$ treatments. These results indicate that GhACS1, which was transiently expressed in response to certain stimuli, may be involved in the production of ethylene for the transmission of stress signals.

• 한국정보과학회논문지:소프트웨어및응용
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• 제30권9호
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• pp.862-866
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• 2003

조합 최적화 문제인 순회 판매원 문제(Traveling Salesman Problem, TSP)를 유전자 알고리즘(Genetic Algorithm)과 Local Search Heuristic인 Lin-Kernighan(LK) Heuristic［1］을 이용하여 접근하는 것은 최적 해를 구하기 위해 널리 알려진 방법이다. 본 논문에서는 TSP 문제를 해결하기 위한 또 다른 접근법으로 ACS(Ant Colony system) 알고리즘을 소개하고 새로운 페로몬 갱신 방법을 제시하고자 한다. ACS 알고리즘은 다수의 개미들이 경로를 만들어 가는 과정에서 각 에지상의 페로몬 정보를 이용하며, 이러한 반복적인 경로 생성 과정을 통해 최적 해를 발견하는 방법이다. ACS 기법의 전역 갱신 단계에서는 생성된 모든 경로들 중 전역 최적 경로에 속한 에지들에 대하여 페로몬을 갱신한다. 그러나 본 논문에서는 전역 갱신 규칙이 적용되기 전에 생성된 모든 에지에 대하여 페로몬을 한번 더 갱신한다. 이 때 페로몬 갱신을 위해 각 에지들의 발생 빈도수를 이용한다. 개미들이 생성한 전체 에지들의 발생 빈도수를 페로몬 정보에 대한 가중치(weight)로 부여함으로써 각 에지들에 대하여 통계적 수치를 페로몬 정보로 제공할 수 있었다. 또한 기존의 ACS 알고리즘보다 더 빠른 속도로 최적 해를 찾아내며 더 많은 에지들이 다음 번 탐색에 활용될 수 있게 함으로써 지역 최적화에 빠지는 것을 방지할 수 있다.

• Journal of Nutrition and Health
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• 제36권4호
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• pp.376-381
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• 2003

본 연구에서는 흰쥐 간장에 있어서 아실-CoA 합성효소 4의 세포내 소기관의 존재 여부를 확인함과 동시에 fasting, high fat diet, fat-free high sucrose diet, 퍼옥시솜 증식 인자인 DEHP [Di-(2-ethylhexyl)phthalate]를 급여한 흰쥐 간장에 있어서 ACS4의 발현에 대하여 조사하였다. ACS4는 ACSI과 마찬가지로 흰쥐 간장의 마이크로솜, 미토콘드리아와 퍼옥시솜에 존재하는 것으로 생각되며 미토콘드리아에서 가장 많은 단백질이 검출되었다. ACS4 mRNA는 절식하였을 때와 high fat diet, fat-free high sucrose diet을 급여하였을 때는 대조군에 비하여 2.3배 발현이 증가하였으며 DEHP을 급여하였을 때는 3.9배 mRNA의 증가를 나타내었다. 이러한 결과를 종합하여 보면 간장에 있어서 ACS4는 기본적인 $\beta$-산화뿐만 아니라 호르몬에 의한 조절과 간접적으로는 인슐린에 의한 조절도 받는 것으로 생각되며 다양한 기능을 수행하고 있음을 추측할 수 있다.

• 생약학회지
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• 제50권2호
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• pp.141-147
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• 2019

The aim of this study was to investigate the potential of Acanthopanax sieboldianum (Makino) Koidz (ACS) as a potent antioxidant and antidiabetic agent. The antioxidative and alpha-glucosidase inhibitory activities were examined using the methanol extracts and solvent fractions from ACS-leaf and ACS-stem. Antioxidative activities were measured by in vitro methods such as DPPH and ABTS radical scavenging activity and superoxide dismutase (SOD) activity. When the chloroform and ethyl acetate fractions of ACS-leaf and ethyl acetate fractions of ACS-stem were compared with the control, the SOD-like activity was impaired even at the low treatment concentrations. In addition, the ethyl acetate fractions of ACS-leaf and ACS-stem showed alpha-glucosidase inhibition activities at low treatment concentrations. Analysis of the major components in the fractions of ACS-leaf and ACS-stem was also performed using HPLC. Finally, astragalin, isoqurecetin, chlorogenic acid and caffeic acid contents were measured. Based on this work, we propose that ACS-leaf and ACS-stem have great potential as natural antioxidant and antidiabetic materials related to health benefits.