• 한국환경성돌연변이발암원학회지
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• 제15권2호
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• pp.100-105
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• 1995

The effects of DNA polymerase $\beta$ on the somatic chromosome mutations and mitotic recombinations were investigated using the transgenic Drosophila beating chimetic gene consisting of a promoter region of Drosophila actin 5C gene and rat DNA polymerase $\beta$. For detecting the somatic chromosome mutations and mitotic recombinations, the heterozygous (mwh/+) strains possessing or lacking transgene poi 13 were used. The spontaneous frequency of small mwh spots, due to deletion or nondisjunction etc., in the non-transgenic w strain and the transgenic p[pol $\beta$]-130 strain was 0.351 and 0.606, respectively. The spontaneous frequency (0.063) of large mwh spots, arises mostly from somatic recombination between the centromere and the locus mwh, in the transgenic p[pol $\beta$]-130 strain was about three times higher than that (0.021) of the non-transgenic w strain. The mutant clone frequencies of small and large mwh spots induced by N-methyl-N'-nitro-N-nitrosoguanidine and ethyl methanesulfonate in the transformant p[pol $\beta$]-130 were higher than those in the host strain w. The present results suggest that rat DNA polymerase $\beta$ participate at least in the somatic chromosome mutations and mitotic recombination processes.

• Clinical and Experimental Pediatrics
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• 제48권4호
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• pp.425-432
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• 2005

목 적 : 폴리글루타민 질환은 해당 발현단백질의 연속되는 글루타민 아미노산 서열이 신장되기 때문에 일어나는 질환군이다. 현 연구는 폴리글루타민 질환 형질전환 초파리 모델들이 환자들 에서와 유사한 장애를 나타내는지 확인하기 위해 수행되었다. 방 법 : 폴리글루타민 질환 (SCA3) 형질전환 초파리를 대상으로 벽을 기어오르는 운동 능력을 검사하였다. 또한 유전학적인 방법을 통해서 아폽토시스를 억제하는 bcl-2 유전자와 화학적 샤페론이 뇌신경의 퇴행에 어떤 영향을 미치는지 확인하였으며 향후의 연구를 위해 척수소뇌 운동실조증 타입 2 (SCA2) 질환을 발현하는 형질전환 초파리를 생산하였다. 결 과 : SCA3 형질전환 초파리에서 신장된 폴리글루타민 배열을 지니는 질환성 초파리의 경우 신경계에서 해당 단백질을 발현하였을 경우 전형적인 운동 능력 상실을 나타냈다. 아폽토시스를 억제하는 유전자인 bcl-2를 함께 발현했을 경우, 신장된 단백질의 유독한 영향을 약화시키지 못했지만, 화학적 샤페론인글리세롤의 경우 적어도 눈에서의 유독한 영향은 억제하는 것으로 보인다. 본 연구진에 의해 개발된 SCA2 형질전환 초파리의 경우 유해 단백질의 발현 정도가 낮아서 정확한 분석이 어려웠다. 결 론 : SCA3 형질전환 초파리는 환자들에서 발견되는 운동실조증을 보였다. 글리세롤과 같은 화학적 샤페론이 현재 치료가 전무한 이 종류의 질환군의 치료에 효과적일 것으로 사료된다.

• Molecules and Cells
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• 제27권5호
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• pp.583-589
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• 2009

GTP cyclohydrolase I (GTPCH) is a key enzyme in the de novo synthesis of tetrahydrobiopterin. Previously, the Drosophila melanogaster GTPCH gene has been shown to be expressed from two different promoters (P1 and P2). In our study, the 5'-flanking DNA regions required for P1 and P2 promoter activities were characterized using transient expression assay. The DNA regions between -98 and +31, and between -73 and +35 are required for efficient P1 and P2 promoter activities, respectively. The regions between -98 and -56 and between -73 and -41 may contain critical elements required for the expression of GTPCH in Drosophila. By aligning the nucleotide sequences in the P1 and P2 promoter regions of the Drosophila melanogaster and Drosophila virilrs GTPCH genes, several conserved elements including palindromic sequences in the regions critical for P1 and P2 promoter activities were identified. Western blot analysis of transgenic flies transformed using P1 or P2 promoter-lacZ fusion plasmids further revealed that P1 promoter expression is restricted to the late pupae and adult developmental stages but that the P2 promoter driven expression of GTPCH is constitutive throughout fly development. In addition, X-gal staining of the embryos and imaginal discs of transgenic flies suggests that the P2 promoter is active from stage 13 of embryo and is generally active in most regions of the imaginal discs at the larval stages.

• 한국응용곤충학회지
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• 제35권4호
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• pp.315-320
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• 1996

Drosophila의 actin 5C 유전자 promoter에 쥐의 DNA polymerase $\beta$cDNA를 도입시킨 형질전환 초파리가 고감수성 환경성 변이원 검출계로 사용할 수 있는지를 조사하였다. 체세포 염색체 재조환과 체세포 염색체 돌연변이의 검출을 위해서는 geterozygous(mwh/+) 계통을 사용하였다. 염색체상의 결실이나 비분리 등에 의한 small mwh spot의 자연 발생적 빈도는 non-transgenic w 계통과 transgenic p[pol $\beta$]-130 계통에서 각각 0.351 및 0.606 정도였다. 체세포 염색체 재조환에 의한 large mwh spot의 자연 발생적 빈도의 경우는 transgenic p[pol $\beta$]-130 계통(0.063)이 non-transgenic w 계통(0.021)에 비해 약 3배 정도 높게 나타났다. IQ, Glu-P-1 및 {TEX}$AFB_{1}${/TEX} 등의 돌연변이원의 처리에 의한 경우, 두 종류의 mutant clone의 발생 빈도는 쥐의 DNA polymerase $\beta$가 도입된 transgenic p[pol $\beta$]-130 계통이 non-transgenic w 계통에 비하여 모두 약 2-3배 정도 높게 나타났다. 본 연구의 결과는 쥐의 DNA polymerase $\beta$가 최소한 체세포 염색체 돌연변이 유발이나 체세포 염색체 재조환의 생성 과정에 관여함을 의미하며, 형질전환 초파리 계통이 환경성 변이원 검출계로서 충분한 응용가능성이 있음을 보여 주었다.

• BMB Reports
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• 제45권10호
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• pp.577-582
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• 2012

single-minded (sim) is a master regulatory gene that directs differentiation in the central nervous system during Drosophila embryogenesis. Recent identification of the mesectoderm enhancer (MSE) of sim has led to the hypothesis that two Snail (Sna)-binding sites in the MSE may repress sim expression in the presumptive mesoderm. We provide evidence here that three Sna-binding sites proximal to the sim promoter, but not those of the MSE, are responsible for the mesodermal repression of sim in vivo. Using transgenic embryos injected with lacZ transgenes, we showed that sim repression in the mesoderm requires the three promoter-proximal Sna-binding sites. These results suggest that Sna represses the mesectodermal expression of sim by directly repressing the nearby promoter, and not by quenching adjacent transcriptional activators in the MSE. These data also showed how the MSE, lacking the three proximal Sna-binding sites, reproduced the endogenous pattern of sim expression in transgenic embryos.

• Animal cells and systems
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• 제1권4호
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• pp.637-640
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• 1997

Raf-1, a cytoplasmic serine/threonine protein kinase, serves as a central intermediate in many signaling pathways in cell proliferation, differentiation, and development. In this study, we investigated that B-raf, Drosophila homolog of the human c-raf-1, is involved in ultraviolet (UV) responsive events by using hypomorphic mutant $D-raf^{c110}$ and Draf-lacZ transgenic fly. At first, effect of UV damage on the survival of wild-type and $D-raf^{C110}$ strains was examined. In terms of $1/LD_{50}$ value, the relative ratio of UV sensitivities of wild-type versus $D-raf^{C110}$ strain was 1 : 2.2. By using quantitative $\beta$-galactosidase activity analysis, transcriptional activity of the D-raf gene promoter was also examined in UV-irradiated Draf-lacZ transgenic larvae. UV irradiation increased the expression of lacZ reporter gene in Draf-lacZ transgenic fly. However, in $D-raf^{C110}$ strain the transcriptional activity of D-raf gene promoter by UV irradiation was extensively reduced. Results obtained in this study suggest that D-raf plays a role in UV response, leading to better survival of Drosophila to UV damage.

• Animal cells and systems
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• 제2권2호
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• pp.269-275
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• 1998

The reporter plasmid pMT-lacZ containing the metallothionein (MT) promoter region (-320∼+58 with respect to the transcription initiation site) fused to the lacZ gene in a P-element vector was constructed. Transgenic Drosophila bearing the MT-lacZ fusion gene were established by P-element mediated transformation. Expression of the MT-lacZ fusion gene in transformants was examined during development. By treatment with low concentration of cadmium (>1O uM) or paraquat (>50 uM), increased expression of B-galactosidase was shown in fat body, brain lobe, and ganglion transgenic larval tissues. The results show that transformants bearing the MT-lacZ fusion gene are useful for further studies on the mechanism of regulation of MT gene expression and for monitoring toxic metals.

• 동의신경정신과학회지
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• 제19권2호
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• pp.151-163
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• 2008

Objective : Recent studies indicate that the deposition of beta-amyloid ($A{\beta}$) is related in the pathogenesis of Alzheimer's disease (AD), but the underlying mechanism is still not clear. Method : To investigate the potential cellular functions of APP and LMK02, we use transgenic drosophila as a model was treated with either LMK02, and the effect in APP expression was determined by climbing assay. LMK02 have been shown to be neuroprotective in fly model systems. We asked whether dietary supplementation with LMK02 would influence behavior and AD-like pathology in a transgenic fly model. Result LMK02 water extract have attenuated fly death in vivo. LMK02-treated fly increased percentage of flight ability more longly and survival ratio more than controls. APP-GRIM drosophila treated with LMK02 had significantly less accumulation of APP deposition in the eye and brain as compared to control drosophila. Conclusion : These results suggest that LMK02 prevent APP-induced neurotoxicity through attenuating flies death induced by APP, and may be useful as potential therapeutic agents for AD.

• 생명과학회지
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• 제9권1호
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• pp.50-57
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• 1999

STAT들은 다양한 cytokine이나 성장호르몬 등에 의해 활성화되어 핵으로 빠르게 이동되어 유전자 발현을 조절한다. 우리는 D-raf 유전자의 5' 발현조절영역에서 STAT결합부위 염기서열을 발견하였다. 본 연구는 D-raf 유전자발현조절에 있어서 STAT결합부위의 역할을 형질전환 초파리를 사용하여 조사하였다. STAT결합부위에 염기치환돌연변이를 도입시킨 D-raf promoter부분을 P인자 벡터의 IacZ유전자에 융합시킴으로써 리포터 플라스미드 pDraf-STATmut-lacZ를 제작하였다. 이 리포터 플라스미드를 이용하여 얻은 Draf-STATmut-lacZ형질전환 초파리의 lacZ발현을 발생단계별, 조직별로 조사한 결과, 거의 모든 발생단계에서 정상형 Draf-lacZ 형질전환 초파리의 lacZ발현에 비해 크게 감소하였다. 본 연구결과들은 STAT결합배열 부위가 D-raf유전자발현조절에 있어서 중요한 역할을 함을 개체수준에서 증명하고 있다.

• 한양메디칼리뷰
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• 제34권3호
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• pp.130-136
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• 2014

Animals find nutritious foods to survive, while avoiding aversive and toxic chemicals through the chemosensory faculties of olfaction and taste. The olfaction is comparatively well characterized, but the studies of taste are only recently developing since after 2000. Genetic, immunohistochemistry, and electrophysiological studies with knock-out transgenic mice opened up the taste field in mammals. Taste in insects has been only recently been studied after mammalian taste receptors were identified. Flies also discriminate the differences of sweet, salty and sour food, while being able to detect and reject potential foods contaminated with toxins or detrimental chemicals. These discriminatory abilities indicate that flies house basic taste receptors in their taste organs like humans. For the last decade, the sweet and bitter gustatory receptors in Drosophila have been characterized. In this review, we compare the taste anatomy between humans and insects. We also introduce five canonical taste sensations in Drosophila. In addition, we introduce new taste repertoires, that fruit flies can sense water and fatty acids as well as the carbonation buffer in beverage. These studies on simple model organisms will open up a new potential for scientists to further investigate these characteristics in vertebrates.