• Journal of Life Science
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• 제11권1호
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• pp.52-56
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• 2001

The present study intends to characterize the DNA damage-inducible responses in eukaryotic cells. The fission yeast, S. pombe, which displays efficient DNA repair systems, was used in this study as a model system for higher eukaryotes. To study UV-inducible responses in S. pombe, five UV-inducible cDNA clones were isolated from S. pombe by using subtration hybridization method. To investigate the expression of isolated genes, the cellular levels of the transcripts of these genes were determined by Northern blot analysis after UV-irradiation. The transcripts of isolated gene (UV130) increased rapidly and reached maximum accumulation after UV-irradiation. Compared to the message levels of control, the levels of maximal increase were approximately 5 fold to UV-irradiation. In order to investigation whether the increase of UV130 transcripts was a specific results of UV-irradiation, UV130 transcript levels were examined after treating the cells to Methylmethane sulfonate (MMS). The transcripts of UV130 were not induced by treatment of 0.25% MMS. These results implied that the effects of damaging agents are complex and different regulatory pathways exist for the induction of these genes. To characterize the structure of UV130 gene, nucleotide sequences were analyzed. The nucleotide sequence of 1,340 nucleotide excluding poly(A) tail contains one open reading frame, which encodes a protein of 270 amino acids. The predicted amino acid sequences of UV130 do not exhibit any significant similarity to ther known sequences in the database.

• 생명과학회지
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• 제16권4호
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• pp.704-709
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• 2006

본 연구는 DNA 상해유도기작을 규명하기 위하여 꼬마선충 (Caenorhabditis elegans) 으로 부터 subtraction hybridization 방법을 이용하여 자외선 유도 유전자인 UV100과 UV150을 분리하고 그 유전자 구조와 발현양상을 조사하였다. 분리한 유전자의 발현양상을 Northern hybridization 방법으로 살펴본 결과 자외선 조사 후에 최대 2배 이상의 발현 증가를 나타내었다. 이 결과 이미 밝혀진 다른 UV-inducible 유전자와 유사하게 UV100과 UV150 유전자는 자외선에 의해서만 발현이 증가됨을 알 수 있었다. 또한 분리한 유전자의 기능을 알기 위하여 RNAi 실험을 한 결과 분리한 자외선 유도유전자는 발생단계에 따라 다양한 DNA 회복기작을 나타냄을 알 수 있었다.

• Environmental Analysis Health and Toxicology
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• 제21권1호
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• pp.21-26
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• 2006

본 연구는 DNA 상해유도기작을 규명하기 위하여 하등 진핵생물인 분열형 효모 Schizosaccharomyces pombe로부터 subtraction hybridization방법을 이용하여 자외선 유도 유전자인 UV150과 UV200을 분리하고 그 유전자 구조와 발현양상을 조사하였다. 분리한 유전자의 발현양상을 Northern hybridization 방법으로 살펴본 결과 자외선 조사 1시간 후부터 발현이 증가되었다. 또한 알킬화제인 Methyl Methanesulfonate (MMS) 처리에 의해서도 발현이 증가되었다. 이 결과 다른 UV-inducible유전자와는 다르게 분리한 UV150유전자는 UV에 UV200유전자는 MMS에 의하여 발현이 증가됨을 알 수 있었다. 유전자의 기능을 알기 위하여 URA4 유전자를 이용하여 null-mutant 세포주를 제조하여 그 특성을 살펴본 결과 분리한 UV150 유전자는 세포의 성장에 필수적인 유전자임을 알 수 있었다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 한국생물과학협회 학술발표대회
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• pp.241.1-241
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• 1999

No Abstract, See Full Text

• Journal of Life Science
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• 제10권1호
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• pp.40-44
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• 2000

The SNF2/SW ATPase/helicase family comprises proteins form a variety of species with in vivo functions, such as transcriptional regulation, maintenance of chromosome stability during mitosis, and various types of DNA repair. Here, we reported the characterization of h게2+gene which was iolated by PCR amplification using the conserved domain of SNF2 motifs. Sequence analysis of PCR product showed striking evolutionary conservation among the SNF2 family of proteins. Two transcripts of 6.7 and 3.4 Lb were detected by Northern blot analysis. furthermore, the intensities of these two bands were increased by ultraviolet(UV) irradiation. These results indicate that the hrp2+ is a novel member of the SNF2 family of proteins and is one of the UV-inducible genes in S. pombe. To determine the level of transcripts of hrp2+ gene during cellular growth, Northern blot analysis were performed. This result indicates that the level of hrp2+transcript reached its maximum before cells entered the exponential growth phase. This suggests that hrp2+ gene is experssed mainly at the early stage of cell growth.

• 한국동물학회지
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• 제37권2호
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• pp.232-239
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• 1994

RecA protein plans a central role in homologous recombination and DNA repair in Escherichia cofi (E. colD. The function 8nd structure of this protein are universal in prokarvotes and also conserved in eukaryotes such as yeast. The RecA-like protein with 74 lInDa in size has already been identified and purified from a fission yeast Schizosaccharomyces pombe (5. pommel (Lee, 19911. From this study it was revealed that the RecA-like protein of 5. pombe was highly inducible to various DNA damaging agents and inhibitors of nucleotide pool svnthesizins enzymes. The cellular level of the 5. pombe RecA-like protein wi,u markedly increased, upto 5- to 10-fold, by treatment with various DNA-damains agents including ultraviolet (UV) light, methyl methanesulfonate WS),4-nitroquinoline-1-oxide (4-NQO), and mitomycin-C (MMC), similar to E. cofi RecA protein. Interestingly, the protein level was also increased by inhibitors of nucleotide pool forming enzlwnes such as methotrexate (MTX) and hvdroxvurea (HU). The most effective doses for the inducibility of 4-NQO, MMS, W, MMC, MTX, and HU were 0.2 Ug/ml, 30 mM, 200 J/ma, 0.4 $\mus/ml,$ 1 Ug/ml, and 100 mM, respectively. The range of effective duration time for the inducibilitv of RecA-like protein was from 270 to 450 mins. These results suggest that the 5. pombe RecA-like protein also platys an imortant role in cellular responses to DNA damage as in E. coli system.

• 생명과학회지
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• 제16권1호
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• pp.126-130
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• 2006

본 연구는 DNA상해유도기작을 규명하기 위하여 하등 진핵생물인 분열형 효모 Schizosaccharomyces pombe로부터 subtraction hybridization방법을 이용하여 자외선 유도 유전자인 UVI-155을 분리하고 그 유전자 구조와 발현양상을 조사하였다. UVI-155 유전자의 발현양상을 Northern hybridization 방법으로 살펴본 결과 자외선(ultraviolet-light) 조사 1시간 후에 최대의 발현 증가를 나타내었다. 반면 알킬화제 인 MMS (methyl methanesulfonate) 처리에 의해서도 발현이 증가되었다. 이 결과 다른 UV-inducible 유전자와는 다르게 UVI-l55 유전자는 UV와 MMS 등의 DNA 상해에 모두 발현이 증가됨을 알 수 있었다. 또 한 유전자의 기능을 알기 위하여 null-mutant세포 주를 제조하여 그 특성을 살펴본 결과 이 유전자는 세포의 성장에 필수적인 유전자임을 알 수 있었다.

• Animal cells and systems
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• 제3권2호
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• pp.229-236
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• 1999

The recA gene plays a central role in genetic recombination and SOS DNA repair in Escherichia coli (E. coli). We have previously identified a 42 kDa RecA-like protein inducible by a variety of DNA damages from a fluorescent Pseudomonas strain sp. and characterized its inducible kinetics. In the present study, we cloned and characterized the gene encoding the RecA-like protein by immunological screening of Pseudomonas genomic expression library using polyclonal E. coli anti-RecA antibodies as a probe. From 10$^{5}$ plaques screened, five putative clones were finally isolated. Southern blot analysis indicated that four clones had the same DNA inserts and the recA-like gene was located within the 3.2 kb EcoRI fragment of Pseudomonas chromosomal DNA. In addition, the cloned recA-like gene was transcribed into an RNA transcript approximately 1.1 kb in size, as judged by Northern blot analysis. The cellular level of RNA transcript of the cloned recA-like gene was increased to an average of 5.15- fold upon treatment with DNA damaging agents such as ultraviolet (UV)- light, nalidixic acid (NA), methyl methanesulfonate (MMS), and mitomycin-C (MMC). These results suggest that the cloned gene is inducible by DNA damage similarly to the recA gene in E. coli. However, the cloned gene did not restore the DNA damage sensitivity of the E. coli recA-mutant.

• Animal cells and systems
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• 제7권2호
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• pp.159-164
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• 2003

The RAD3 gene of Saccharomyces cerevisiae is required for excision repair and is essential for cell viability. The RAD3 encoded protein possesses a single stranded DNA-dependent ATPase and DNA and DNA-RNA helicase activities. To examine the extent of conservation of structure and function of a S. pombe RAD3 during eukaryotic evolution, the RAD3 homolog gene was isolated by screening of genomic DNA library. The isolated gene was designated as HRD3 (homolog of RAD3 gene). Southern blot analysis confirmed that S. pombe chromosome contains the same DNA as HRD3 gene and this gene exists as a single copy in S. pombe. The transcript of 2.8 kb was detected by Northern blot analysis, The level of transcripts increased by ultraviolet (UV) irradiation, indicating that HRD3 is one of the UV-inducible genes in S. pombe. Furthermore, the predicted partial sequence of HRD3 protein has 60％ identity to S. cerevisiae RAD3 gene. This homology was particularly striking in the regions identified as being conserved in a group of DNA helicases. Gene deletion experiments indicate that the HRD3 gene is essential for viability and DNA repair function. These observations suggest evolutionary conservation of other protein components with which HRD3 might interact in mediating its DNA repair and viability functions.

• BMB Reports
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• 제42권5호
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• pp.245-259
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• 2009

The process by which adult neural stem cells generate new and functionally integrated neurons in the adult mammalian brain has been intensely studied, but much more remains to be discovered. It is known that neural progenitors progress through distinct stages to become mature neurons, and this progression is tightly controlled by cell-cell interactions and signals in the neurogenic niche. However, less is known about the cell-intrinsic signaling required for proper progression through stages of adult neurogenesis. Techniques have recently been developed to manipulate genes specifically in adult neural stem cells and progenitors in vivo, such as the use of inducible transgenic mice and viral-mediated gene transduction. A critical mass of publications utilizing these techniques has been reached, making it timely to review which molecules are now known to play a cell-intrinsic role in regulating adult neurogenesis in vivo. By drawing attention to these isolated molecules (e.g. Notch), we hope to stimulate a broad effort to understand the complex and compelling cascades of intrinsic signaling molecules important to adult neurogenesis. Understanding this process opens the possibility of understanding brain functions subserved by neurogenesis, such as memory, and also of harnessing neural stem cells for repair of the diseased and injured brain.