• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1996년도 정기총회 및 학술발표회
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• pp.18-18
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• 1996

Bacteriophage T4 endonuclease V initiates the repair of ultraviolet (UV)-induced pyrimidine dimer photoproducts in duplex DNA. The mechanism of DNA strand cleavage involves four sequential steps: linear diffusion along dsDNA, pyrimidine dimer-specific binding, pyrimidine dimer-DNA glycosylase activity, and AP lyase activity. (omitted)

• Bulletin of the Korean Chemical Society
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• 제29권4호
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• pp.879-881
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• 2008

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.183-183
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• 1996

Bacteriophage T4 endonuclease V initiates the repair of ultraviolet (UV)-induced pyrimidine dimer photoproducts in duplex DNA. The mechanism of DNA strand cleavage involves four sequential stens: linear diffusion along dsDNA, pyrimidine dimer-specific binding,l pyrimidine dimer-DNA glycosylase activity, and Af lyase activity. Although crystal structure is known for this enzyme, solution structure has not been yet known. In order to elucidate the solution structure of this enzyme NMR spectroscopy was used. As a basis for the NMR peak assignment of the protein, HSQC spectrum was obtained on the uniformly $\^$15/N-labeled T4 endonuclease V. Each amide peak of the spectrum were classified according to amino acid spin systems by interpreting the spectrum of $\^$15/N amino acid-specific labeled T4 endonuclease V. The assignment was mainly obtained from three-dimensional NMR spectra such as 3D NOESY-HMQC, 3D TOCSY-HMQC. These experiments were carried out will uniformly $\^$15/N-labeled sample. In order to assign tile resonance of backbon atom, triple-resonance theree-dimensional NMR experiments were also performed using double labeled($\^$15/N$\^$13/C) sample. 3D HNCA, HN(CO)CA, HNCO, HN(CA)HA spectra were recorded for this purpose. The results of assignments were used to interpret the interaction of this enzyme with DNA. HSQC spectrum was obtained for T4 endonuclease V with specific $\^$15/N-labeled amino acids that have been known for important residue in catalysis. By comparing the spectrum of enzyme*DNA complex with that of the enzyme, we could confirm the important role of some residues of Thr, Arg, Tyr in activity. The results of assignments were also used to predict the secondary structure by chemical shift index (CSI).

• 약학회지
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• 제25권4호
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• pp.167-173
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• 1981

Spectroscopic investigation has been carried out to know the binding mechanism of riboflavin with barbiturates, such as phenobarbital and amobarbital in chloroform solution by using infrared and nuclear magnetic resonance spectra. Phenobarbital and isoalloxazine form a 1:1 cyclic hydrogen bonded dimer through the 3-N imino and the 2-C carbonyl groups of the isoalloxazine ring of the latter, and the 1-N (or 3-N) imino and the 2-C carbonyl groups of the pyrimidine ring of the former. Amobarbital and riboflavin form a 1:1 cyclic hydrogen bonded dimer by the same mode of phenobarbital.

• Journal of Photoscience
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• 제9권2호
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• pp.448-450
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• 2002

DNA samples extracted from Japanese cypress leaf tissues contain isopropyl alcohol-precipitable, high molecular weight compounds, which interfere ELISA for cyclobutane pyrimidine dimers (CPD). Removal of the compounds is achieved by DEAE ion-exchange column chromatography and improves the ELISA responses of the DNA. When extracting DNA repeatedly from the same leaf tissues, the DNA samples show CPD responses which increase with the order in sequential extraction, and hence for a reliable detennination of DNA lesion a thorough extraction of DNA is required. Clearing these two problems it was demonstrated that CPD level was slightly higher in the leaves of trees growing under full sunlight than in those growing under UBV -cut sunlight.

• Journal of Photoscience
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• 제9권2호
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• pp.162-165
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• 2002

Rice is widely cultivated in various regions throughout Asia. Over a five-year period, we investigated the effects of supplemental UVB radiation on the growth and yield of Japanese rice cultivars in the field. The findings of that study indicated that supplemental UVB radiation has inhibitory effects on the growth and grain development. Furthermore, we investigated the sensitivity to UVB radiation of rice cultivars of 5 Asian rice ecotypes, and found that rice cultivars vary widely in UVB sensitivity. The aim of our study is improving UVB resistance in plants by bioengineering or breeding programs. In order to make it, there is need to find the molecular origin of the sensitivity to UVB. Cyclobutane pyrimidine dimer (CPD) is major UV-induced DNA lesions. Plants possess two mechanisms to cope with such DNA damage. The first is the accumulation of UV-absorbing compounds. Our previous data showed that the steady-state CPD levels in leaves of rice grown under chronic radiation in any culture were not so greatly influenced by the increased UV-absorbing compounds content, although there was a significant positive correlation between the CPD levels induced by challenge UVB exposure and the UV-absorbing compounds content. The other is the repair of DNA damage. Photorepair is the major pathway in plants for repairing CPD. We found that the sensitivity to UVB could seriously correlate with the low ability in CPD photorepair in rice plants. These results suggest that photo lyase might be an excellent candidate for restoration by way of selective breeding or engineering in rice.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2004년도 생명공학 실용화를 위한 비젼
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• pp.29-34
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• 2004

Reduction in stratospheric ozone layer increases the amount of ultraviolet-B radiation (UVB: 280-320 nm) that reaches the earth ’ s surface. UVB radiationcan damage plants, resulting in decrease in growth and productivity. UVB-augmentation studies have indicated that the sensitivity to UVB radiation in plants varies among the species and cultivars. However. there are no definitive answers for the mechanisms of UVB-resistance in higher plants and for bioengineering design and development of UVB-tolerant plants. We have been studying physiological and biochemical aspects of the effects of UVB radiation on growth and yield of rice COryza sativa LJ. aiming to clarify the mechanism of resistance to UVB radiationin rice. At this meeting. weintroduce our research as followed: (1) supplementary UVB radiation has inhibitory effects on the growth. yield and grain development of rice; (2) UVB sensitivity of rice varies widely among cultivars; (3) among Japanese rice cultivars. Sasanishiki. a leading variety in northeast Japan. is more resistant to UVB. while Norin 1. a progenitor of Sasanishiki. is less resistant; (4)UV-sensitive Norin 1 cultivar is deficient in photorepair of UVB-induced cyclobutane pyrimidine dimer (CPD). and this deficiency results from one amino acid residue alteration of CPD photolyase. These results suggest that spontaneously occurring mutation in CPD photolyase gene could lead to difference in UVB sensitivity in rice. and that CPD photolyase might be a useful target for improving UVB-sensitivity in rice by selective breeding or bioengineering of UVB-tolerant rice.

• 한국동물학회지
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• 제25권2호
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• pp.55-62
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• 1982

발생 12일째의 계배근세포를 약 7일간 배양하면서 자외선에 의한 절제회복, 광재활성 및 DNA 복제억제율을 조사하여 다음과 같은 결과를 얻었다. 자외선에 의한 절제회복은 계배근세포의 분화정도가 진행됨에 따라 감소하였으며, 이는 특히 자외선의 선량이 높을수록 뚜렷하였다. DNA 합성율은 분화가 진행된 세포일수록 현저히 감소하는 경향이었으며 각 분화단계에 따른 DNA 복제억제 현상은 배양 초기 세포인 경우 자외선 조사후 30분에서 1시간반 사이에서 가장 심하게 나타났고, 배양후기의 세포에서는 이러한 억제현상이 뚜렷하지 않았다. 또 배양 1일째 세포에서 광재활성에 의한 피리미딘 이량체의 감소율은 자외선 조사직후에 현저하였다가 그후 시간의 경과에 따른 차이는 보이지 않았다. 그러나, 절제회복만에 의한 이량체의 감소는 조사후 시간이 지남에 따라 서서히 감소하여 광재활성에 의한 이량체의 감소량과 비슷한 수준으로 접근하였다.

• Journal of Photoscience
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• 제9권2호
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• pp.329-331
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• 2002

There is a difference in the inhibitory effects to supplemental UVB (wavelengths 280 to 320 nm) among Japanese rice (Oryza sativa L.), the cultivar Norin I is less resistant while the cultivar Sasanishiki is resistant. UVB induces photodamage in DNA. Cyclobutane pyrimidine dimer (CPD) is a major UV-induced DNA lesion. Photorepair, which is mediated by photolyase, is the major pathway in plants for repairing CPD. We have analyzed CPD induction and repair in Sasanishiki and its close relative Norin I using alkaline agarose gel electrophoresis. Norin I is deficient in CPD photoreactivation and excision, thus UV sensitivity correlates with deficient dimer repair [I]. The photorepair deficiency in Norin I results from a functionally altered photolyase with a photoflash analysis [2]. In this paper, we examined the UVB-sensitivity of several other UV-sensitive and -resistant cultivars and found that the CPD photolyase activity was deficient in UV-sensitive ones. It was also evident that there was a variation in the deduced amino acid sequences of CPD photolyases of the UV-sensitive and -resistant cultivars, whereas each deduced amino acid sequence of the UV-sensitive cultivars and of the UV-resistant ones was the same. These results suggest that the difference in the CPD photolyases of UV-sensitive and -resistant rice might be due to the structural alteration of CPD photolyase.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.316-316
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• 1994

자외선 등에 의한 DNA 합성억제의 회복과정에서의 기작을 규명하기 위하여 자외선에 의하여 억제되었던 DNA 합성이 새로운 replication origin을 사용하는 지를 DNA 복제가 일어나는 장소로 알려진 nuclear matrix와 연관지어서 살펴 보았다. 자외선 조사후 새로 합성된 DNA 분자들의 크기는 시간이 경과하여도 대조군의 DNA 분자들의 크기보다 작았으나 그 성장 양상은 차이가 얼었고, 자외선이 조사된 세포에서 parental DNA의 부가적인 결합이 DNA 합성률의 회복에 필요함을 알 수 있었다. 또한 자외선 상해의 회복과정에서 생기는 알카리 민감성 부위는 RNA linker에 의해 생겨남을 알 수 있었다. 이상의 결과들을 종합하여 보면, 자외선에 의해 pyrimidine dimer가 생기면 첫째로 절제회복에 의해 제거되어지지만, 남아 있는 pyrimidine dimel에 의해서 DNA 복제억제는 여전히 억제되어 있다. DNA 복제억제의 회복은 새로운 복제원점이 활성화되어 nuclear matrix에 결합하여 새로운 DNA 합성이 시작됨으로써 이루어진다. 이때 RNA linker는 복제진행시 DNA 상의 gap으로 생긴 tyopological strain을 제거하는데 이용되어진다.