• 한국미생물·생명공학회지
• /
• 제33권2호
• /
• pp.96-105
• /
• 2005

공시균인 S. longwoodensis IFO 14251의 autoregulators 및 receptor gene 탐색의 일환으로 기존의 Streptomyces속 receptor gene의 공통배열을 primer로 이용하여 PCR을 수행하였다. 예상되는 100 bp 크기의 단편을 pUC19 vector에 ligation하여 E. coli $DH5{\alpha}$에 transformation한 후, plasmid를 분리하여 BamHI을 처리하여 $2\%$ agarose gel에 전기영동한 결과, pUC19 외에 receptor gene PCR product가 100 bp 위치에 존재하는 것을 확인하였다. 형질전환된 plasmid로 PCR을 수행한 후, 염기배열을 결정하여 분석한 결과, Streptomyces sp. 유래의 receptor gene의 일부분임이 확인되었다. 따라서 S. longwoodensis IFO 14251에는 lysocellin 생산에 관여한다고 추정되는 autoregulator receptor protein을 코드하는 유전자가 존재할 것으로 예상되어 100 bp의 PCR product를 probe로 이용하여 Southern 및 colony hybridization을 통하여 4.4 kb의 SphI 단편을 가지는 plasmid(pSLT)를 제작하였고 이를 sequencing한 결과, Streptomyces 속 유래의 autoregulator receptor 단백질을 코드하는 유전자와 3개의 open reading frame(651 bp)을 확인하여 sltR이라 명명하였다. 유전자 해석 결과, 기존의 autoregulator receptor proteins과 비교시 $35{\sim}46\%$의 homology를 나타내었다. 재조합 단백질의 발현을 위해, sltR/pET-l7b plasmid를 제작하고 E. coli BL21(DE3)/pLysS을 host cell로 이용하여 재조합 단백질을 발현시켰다. SltR 재조합 단백질의 정제는 DEAE-Sephacel column chromatography와 DEAE-5PW chromatography(HPLC)를 통해 수행하였다. Gel filtration chromatography(HPLC, 55 kDa)와 SDS-PAGE(28 kDa)를 통해 분자량을 확인한 결과, 재조합 단백질은 dimer형태로 존재하는 것으로 확인되었다. 또한, 결합활성에 있어 A-factor type의 autoregulator에 대해 가장 강한 결합활성을 나타내었다.

• Toxicological Research
• /
• 제21권2호
• /
• pp.161-165
• /
• 2005

Bisphenol A (SPA), a environmental endocrine disruptor, is considered to bind to estrogen receptors and to regulate the expressions of estrogen responsive genes. This study was to evaluate the effect of SPA administration on body weight, sex ratio and litter size on 18 days in prenatal periods, the effect of reproductive organ weight and blood hematological values on 24 days postpartum in pregnant mice. The female mice was administrated to low doses of SPA (0, 0.05, 0.5 and 5.0 mg/kg B.W.) by intraperitoneal injection in gestation days $0\~15$ with 5 times at 3 days interval. The maternal body weight, litter size and sex ratios were similar to in all experimental groups, but body weights of male and female offspring was significantly lower in 5.0mg SPA group when compared to any other groups (P<0.05). No treatment-related effects on body weight, ovary weight and blood hematological values were observed in dams on 24 days after delivery. The uterine weight in 5.0mg SPA group was slightly higher than those of any other groups, but not significantly difference. The histological evaluation of ovary in dam mice on 24 days after dilivery was not difference in all experimental groups, but the endometriosis of uterus in dam mice were significantly increased in 0.5mg SPA group when compared to control group. These results indicates that low concentration of SPA should not be considered as a selective reproductive toxicant.

• Archives of Pharmacal Research
• /
• 제28권6호
• /
• pp.722-729
• /
• 2005

With the aim to improve the specificity and to reduce the cytotoxicity of polyethylenimine (PEI), we have synthesized the conjugates of the branched PEI (25 kDa) with transferrin. The trans-ferrin-PEI (TP) conjugates with five compositions were synthesized using periodate oxidation method and confirmed by FT-IR spectroscopy and gel permeation chromatography. The free amine contents of TP conjugates, which were able to condense and deliver DNA, increased as the amount of PEI increased. TP/DNA polyplexes were characterized by measuring gel elec-trophoresis, ethidium bromide fluorescence quenching, particle size and zeta potential of complexes. Complete complexation of the polyplexes was observed above the N/P ratio of 5 in TP/DNA, and above 3 in PEI/DNA, respectively. The zeta potential of the complexes decreased as the amount of transferrin in TP conjugates increased. Transfection efficiency of TP conjugates was evaluated in HeLa cell and Jurkat cell systems. Among the five compositions of TP conjugates, TP-2 system mediated a higher $\beta$-galactosidase gene expression than PEI system in Jurkat cell which was known to express elevated numbers of transferrin receptors. From the results of the cell viability based on MTT assay, TP conjugates showed lower cytotoxicity com-pared with the PEI system. We expect that the TP conjugate can be used efficiently as a non-viral gene delivery vector.

• 한국응용약물학회:학술대회논문집
• /
• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
• /
• pp.89-89
• /
• 2003

Exposure of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes a variety of biological and toxicology effects, most of which are mediated by aryl hydrocarbon receptor (AhR). The ligand-bound AhR as a heterodimer with AhR nuclear translocator (ARNT) binds to its specific DNA recognition site, the dioxin-responsive element (DRE), and it results in increased transcription of CYP1A1 gene. Retinoic acid (RA) regulates the transcription of various genes for several essential functions through binding to two classes of nuclear receptors, the retinoic acid receptor (RAR) and retinoid X receptor (RXR). Constitutive androstane receptor (CAR) also regulates the transcription of gene. In this study, we have examined how RAR, RXR and CAR regulated CYP1A1 in rainbow trout hepatoma cell (RTH 149) using luciferase reporter gene assay system. We did transient transfection with CYP1A1 luciferase reporter gene and treated with TCDD, all-trans RA, 9-cis RA and phenobarbital. Treatment of all-trans RA, 9-cis RA or phenobarbital decreased the TCDD induced transcription of CYP1Al. When we did transient cotransfection with CYP1A1 luciferase reporter gene and RXR, as increase of RXR concentration, the TCDD induced transcription of CYP1A1 was decreased. Transfection with CAR also decreased the TCDD induced transcription of CYP1A1 in RTH 149 cells.

• Archives of Pharmacal Research
• /
• 제26권11호
• /
• pp.892-897
• /
• 2003

Anticancer drugs have serious side effects arising from their poor malignant cells selectivity, Since insulin receptors highly express on the cytomembrane of some kind of tumor cells, using insulin as the vector was expected to reduce serious side effects of the drugs. The objective of this study was to evaluate the tumor targeting effect of the newly synthesized mitoxantrone-insulin conjugate (MIT-INS) with the drug loading of 11.68%. In vitro stability trials showed MIT-INS were stable in buffers with different pH (2-8) at $37^{\circ}C$ within 120 h (less than 3% of free MIT released), and were also stable in mouse plasma within 48 h (less than 1 % of free MIT released). In vivo study on tumor-bearing mice showed that, compared with MIT [75.92 $\mu g \cdot$ h/g of the area under the concentration-time curve (AUC) and 86.85 h of mean residence time (MRT)], the conjugates had better tumor-targeting efficiency with enhanced tumor AUC of 126.53 1l9 h/g and MTR of 151.95 h. The conjugate had much lower toxicity to most other tissues with targeting indexes ($TI^c$) no larger than 0.3 besides good tumor targeting efficiency with $TI^c$ of 1.67. The results suggest the feasibility to promote the curative effect in ca.ncer chemotherapy by using insulin as the vector of anti-cancer drugs.

• 한국환경독성학회:학술대회논문집
• /
• 한국환경독성학회 2003년도 추계국제학술대회
• /
• pp.179-179
• /
• 2003

Exposure of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes a variety of biological and toxicology effects, most of which are mediated by aryl hydrocarbon receptor (AhR). The ligand-bound AhR as a heterodimer with AhR nuclear translocator (ARNT) binds to its specific DNA recognition site, the dioxin-responsive element (DRE), and it results in increased transcription of CYP1A1 gene. Retinoic acid (RA) regulates the transcription of various genes for several essential functions through binding to two classes of nuclear receptors, the retinoic acid receptor (RAR) and retinoid X receptor (RXR). Constitutive androstane receptor (CAR) also regulates the transcription of gene. In this study, we have examined how RAR, RXR and CAR regulated CYP1A1 in rainbow trout hepatoma cell (RTH 149) using luciferase reporter gene assay system. We did transient transfection with CYP1A1 luciferase reporter gene and treated with TCDD, all-trans RA, 9-cis RA and phenobarbital. Treatment of all-trans RA, 9-cis RA or phenobarbital decreased the TCDD induced transcription of CYP1A1. When we did transient cotransfection with CYP1A1 luciferase reporter gene and RXR, as increase of RXR concentration, the TCDD induced transcription of CYP1A1 was decreased. Transfection with CAR also decreased the TCDD induced transcription of CYP1A1 in RTH 149 cells.

• 한국응용곤충학회지
• /
• 제22권4호
• /
• pp.293-299
• /
• 1983

강남콩 렉틴과 근류균(R. phaseoli)의 결합에 관한 광범위한 실험을 수행하여 다음과 같은 결과를 얻었다. 1. 강남콩종자의 자엽에서 가장 많은 렉틴은 성장에 따라 뿌리로 이동하였는데 발아후 약 5일경에, 뿌리의 길이가 $6\~8cm$인 것이 가장 렉틴의 함량이 많았다. 2. 근류균의 배양시기에 따가 강남콩렉틴과의 응집력을 측정 한 결과 배양초기 가 후기보다 응집력이 높았다. 3. 강낭콩종자에 존재하는 렉틴을 추출 정제하여서 6종 근류균과의 응집력을 측정한 결과 R. phaseoli와의 응집이 가장 강했고 이는 렉틴에 대한 특이적 결합, 즉 숙주특이성을 입증하는 것이었다. 4. 단당류에 의한 응집반응의 경쟁적 저해를 시도함으로써 강남콩렉틴의 근류균에 대한 결합부위가 mannose와 galactose를 포함한 oligosaccharides가는 것을 알수 있었으며 이들의 저해효과에 필요한 당의 최소농도는 6.25mM로서 측정되었다. 5. R. phaseoli와 강낭콩 렉틴을 강낭콩 뿌리에 인공감염시켜본 결과 렉틴의 경쟁적 저해가 확인되었으므로 뿌리혹형성에 렉틴의 가교가 관여한다는 가설을 입증할 수 있었다. 6. Immunodiffusion에 의한 R. phaseoli의 항원 결정기는 R. japonicum과 일부 관련성이 있을뿐 다른 Rhizobium spp.과는 전혀 다른 것으로 나타났다.

• 대한본초학회지
• /
• 제35권3호
• /
• pp.1-8
• /
• 2020

Objectives : In this study, we examined the estrogenic activities and anti-osteo clastogenesis effects of PCE17, a mixture of PE (an extract of Puerariae Flos), and CE (an extract of Citri Unshius Pericarpium). Methods : The estrogenic effect of PCE17, PE and CE were examined by ER-β/ERE reporter gene assay and proliferation assay in 293 T and MCF-7 cells. The expression of estrogen-responsive gene and protein were checked by Real Time-PCR (RT-PCR) and Western blotting in MCF-7 cells. Inhibitory effect of PCE17, PE and CE on RANKL-induced osteoclast differentiation were evaluated by TRAP staining and RT-PCR in primary osteoclast precursors from rat bone marrow cells. Results : PCE17 and PE bind to ERs (estrogen receptors) and show estrogenic activities in 293T cells. They also stimulated the proliferation of MCF-7 cells and increased the expression of ER response gene, pS2. Tectorigenin, an active ingredient of PE, shows similar estrogenic activities in MCF-7 cells. PCE17 and CE inhibited RANKL-induced osteoclastogenesis in rat primary osteoclast precursor cells and down-regulated the osteoclast-specific genes of Nfatc1, Ctsk, and Acp5. Conclusions : In conclusion, PCE17 may have therapeutic potential in cases of menopause and osteoporosis.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권14호
• /
• pp.6073-6080
• /
• 2015

Background: Melanoma differentiation-associated gene-7 (MDA-7)/interleukin-24 (IL-24), a unique tumor suppressor gene, has killing activity in a broad spectrum of cancer cells. Herein, plasmids producing mda-7 proteins fused to different RGD peptides (full RGD4C and shortened RGD, tRGD) were evaluated for apoptosis induction with a hepatocellular carcinoma cell line, Hep-G2. The study aim was to improve the apoptosis potency of mda-7 by tethering to RGD peptides. Materials and Methods: Three plasmids including mda-7, mda-7-RGD and mda-7-tRGD genes beside a control vector were transfected into Hep-G2 cells. After 72 hours incubation, cell viability was evaluated by MTT assay. In addition, the rate of apoptosis was analyzed by flow cytometry using PI/annexin staining. To detect early events in apoptosis, 18 hours after transfection, expression of the BAX gene was quantified by real time PCR. Modeling of proteins was also performed to extrapolate possible consequences of RGD modification on their structures and subsequent attachment to receptors. Results and Conclusions: In MTT assays, while all mda-7 forms showed measurable inhibition of proliferation, unmodified mda-7 protein exhibited most significant effect compared to control plasmid (P<0.001). Again, flow cytometry analysis showed a significant apoptosis induction by simple mda-7 gene but not for those RGD-fused mda-7 proteins. These findings were also supported by expression analysis of BAX gene (P<0.001). Protein modelling analysis revealed that tethering RGD at the end of IL-24/Mda7 disrupt attachment to cognate receptor, IL-20R1/IL-20R2. In conclusion, fusion of RGD4C and shortened RGD peptides to carboxyl terminal of mda7, not only reduce apoptosis property in vitro but also disrupt receptor attachment as demonstrated by protein modelling.

• 한국발생생물학회지:발생과생식
• /
• 제10권1호
• /
• pp.55-61
• /
• 2006

콩류 섭취가 유방암이나 골다공증, 그리고 심혈관계 질환 예방에 도움이 된다는 사실은 학계는 물론 일반인들에까지 큰 관심을 불러 일으키고 있다. 그러나 콩류, 특히 그 주성분인 genistein(GS)이 상기한 긍정적인 효과 외에도 여성의 생식계에 잠재적으로 부정적인 영향을 미칠 가능성에 대한 의문이 계속되어 왔다. 본 연구에서는 GS가 암컷 흰쥐의 사춘기 개시에 미치는 효과와 호르몬 수용체 등 이때의 다양한 생식 지표들의 변화들 조사하였다. GS(100mg/kg/day i.p.)를 생후 25일부터 사춘기 개시의 지표인 최초의 질구 개방(vaginal opening, VO)이 일어나는 날까지 투여하였다. 다음 날 희생시킨 후 난소와 자궁의 외양 변화와 조직 무게를 측정하여 GS가 이들 조직의 세포분열에 미치는 효과를 확인하였고, 조직절편의 현미경 관찰을 통해 해부학적인 변화 양상을 조사하였다. 한편 채취한 혈액내의 LH 수준은 방사면역측정법(RIA)로 측정하였다. 또한 자궁 성숙의 지표가 되는 프로게스테론 수용체(PR)의 mRNA 수준에 대한 정량적인 RT-PCR 조사를 수행하였다. GS 투여에 의해 질구 개방이 앞당겨짐이 확인되었고 ($35.3{\pm}0.7$ day in control group vs $31.2{\pm}0.6$ day in GS group, p<0.0l), 이 때 GS군의 체중이 대조군에 비해 유의하게 낮음을 관찰하였다. 난소와 자궁의 크기와 무게, 그리고 혈중 LH 수준이 GS군에서 유의하게 증가함이 관찰되었다. GS군의 난소에서는 성숙의 지표가 되는 그라프 난포(Graafian follicle)와 황체가 관찰되었으나 대조군의 난소는 미성숙한 난포들만이 관찰되었다. 자궁의 경우도 GS군에서는 내막층과 근막층은 물론 상피층까지 잘 발달된 과다 성장 상태와 함께 분비선 수의 증가가 나타났으나 대조군에서는 모든 세포층의 발달이 미약한 상태였다. 이러한 결과들은 GS의 에스트로겐 유사 효과에 기인하는 것으로 보인다. RT-PCR에서 난소와 자궁에서의 PR mRNA 수준은 GS 투여에 의해 발현 증가가 나타났다. 결론적으로, 본 연구는 사춘기 전 특정 시기에 단기적인 GS 투여에 의해 암컷 흰쥐의 생식계가 활성화되고, 그 결과 조기 사춘기가 유도될 수 있음을 시사한다.