• Biotechnology and Bioprocess Engineering:BBE
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• 제5권6호
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• pp.449-455
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• 2000

Pseudomonas sp. strain DJ-12 is a bacterial isolate capable of degrading 4-chlorobiphenyl (4CBP) as a carbon and energy source. The catabolic degradation of 4CBP by the strain DJ-12 was studied along with the genetic organization of the genes responsible for the crucial steps of the catabolic degradation. The catabolic pathway was characterized as being conducted by consecutive reactions of the meta-cleavage of 4CBP, hydrolytic dechlorination of 4-chlorobenzoate (4CBA), hydroxylation of 4-hydroxybenzoate, and meta-cleavage of protocatechuate. The pcbC gene responsible for the meta-cleavage of 4CBP only showed a 30 to 40% homology in its deduced amino acid sequence compared to those of the corresponding genes from other strains. The amino acid sequence of 4CBA-CoA dechlorinase showed an 86% homology with that of Pseudomonas sp. CBS3, yet only a 50% homology with that of Arthrobacter spp. However, the fcb genes for the hydrolytic dechlorination of 4CBA in Pseudomonas sp. DJ-12 showed an uniquely different organization from those of CBS3 and other reported strains. Accordingly, these results indicate that strain DJ-12 can degrade 4CBA completely via meta-cleavage and hydrolytic dechlorination using enzymes that are uniquely different in their amino acid sequences from those of other bacterial strains with the same degradation activities.

• 한국수정란이식학회지
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• 제12권2호
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• pp.161-169
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• 1997

This study was conducted to compare the insemination time of bovine oocytes and determine the effects of glucose(1.5 mM) on the development of bovine embryos at early cleavage stage. Oocytes were matured for 24 h, followed by exposure to sperm and cultured in modified Tyrode's media drops or with bovine oviduct epithelial cell monolayer prepared in TCM199(BOECM). Insemination time and culture system were varied in each experiment. In experiment 1, to investigate the developmental capacity of bovine embryos after different time of exposure to sperm, bovine ova and sperm were co-incubated for 18, 30 or 54 h, respectively. The development to blastocysts of 30 and 54 h insemination groups were significantly higher(P<0.05) than 18 h group, and in case of blastocysts of cleaved embryos, 30 h group were significantly higher(P<0.05) than other groups. In experiment 2, we investigated the effect of glucose on early bovine embryos. After 18 h insemination, in vitro fertilized oocytes were separated following 3 groups ; G+0, C+24 and C+48. Oocytes of G+0 group were cultured in glucose added Tyrode's medium after fertilization, oocytes in C+24 and C+48 groups were cultured in glucose free Tyrode's medium after fertilization. After 24 h culture, G+24 group was moved to glucose added medium. All oocytes of 3 groups were moved to BOECM after 48 h culture. The rates of cleavage and development to blastocysts in G+0 group were significantly lower than other groups. In experiment 3, we determined the effects of glucose exposure from 8 to 20 h after insemination on the cleavage and development of oocytes. The oocytes in glucose added group had high capacity of cleavage and further development. This study shows that in bovine oocytes, the optimal exposure to sperm is 30 h and glucose exposure to bovine one-cell embryos is detrimental to their first cleavage and further development in vitro but there has no evidence of detrimental effect of glucose(1.5 mM) exposure to bovine embryos over the two-cell stage in vitro.

• 생명과학회지
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• 제24권12호
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• pp.1378-1382
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• 2014

Phospholipase D (PLD)는 세포막을 구성하는 주요지질인 인지질을 분해하여, 이차신호전달물질인 phosphatidic acid (PA)를 생성함으로써 세포의 성장 및 증식, 생존신호전달등 세포내 다양한 생리현상을 조절하는 중요한 신호전달 핵심단백질로 대두되고 있다. PLD의 비정상적인 발현과 활성은 다양한 암을 비롯한 여러 질환에서 나타난다. PLD에 의해 생성된 PA는 세포사멸 유전자의 발현을 감소시켜서 세포사멸에 대한 내성을 나타내고 있다.최근에, 세포사멸과정에서 PLD 단백질의 turnover dynamics에 관한 분자수준에서의 연구가 규명되었다. PLD는, 세포사멸시 활성화되는 단백질 분해효소인 caspases의 새로운 기질로 작용하여 세포사멸을 차별적으로 조절을 한다. Caspase에 의한 PLD동위효소의 차별적인 분해양상이 PLD의 효소활성과 세포사멸억제 기능을 조절한다. 그래서 PLD는 암치료의 표적분자로서의 가능성이 제시된다. 본 리뷰논문에서, 세포사멸조절 PLD의 기능적 역할에 대해 서술하고자 한다.

• Journal of Microbiology
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• 제41권3호
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• pp.239-247
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• 2003

The LRV1-4 capsid protein possesses an endoribonuclease activity that is responsible for the single site-specific cleavage in the 5' untranslated region (UTR) of its own viral RNA genome and the formation of a conserved stem-loop structure (stem-loop IV) in the UTR is essential for the accurate RNA cleavage by the capsid protein. To delineate the nucleotide sequences, which are essential for the correct formation of the stem-loop structure for the accurate RNA cleavage by the viral capsid protein, a wildtype minimal RNA transcript (RNA 5' 249-342) and several synthetic RNA transcripts encoding point-mutations in the stem-loop region were generated in an in vitro transcription system, and used as substrates for the RNA cleavage assay and RNase mapping studies. When the RNA 5' 249-342 transcript was subjected to RNase T1 and A mapping studies, the results showed that the predicted RNA secondary structure in the stem-loop region using FOLD analysis only existed in the presence of Mg$\^$2＋/ ions, suggesting that the metal ion stabilizes the stem-loop structure of the substrate RNA in solution. When point-mutated RNA substrates were used in the RNA cleavage assay and RNase T1 mapping study, the specific nucleotide sequences in the stem-loop region were not required for the accurate RNA cleavage by the viral capsid protein, but the formation of a stem-loop like structure in a region (nucleotides from 267 to 287) stabilized by Mg$\^$2＋/ ions was critical for the accurate RNA cleavage. The RNase T1 mapping and EMSA studies revealed that the Ca$\^$2＋/ and Mn$\^$2＋/ ions, among the reagents tested, could change the mobility of the substrate RNA 5' 249-342 on a gel similarly to that of Mg$\^$2＋/ ions, but only Ca$\^$2＋/ ions identically showed the stabilizing effect of Mg$\^$2＋/ ions on the stem-loop structure, suggesting that binding of the metal ions (Mg$\^$2＋/ or Ca$\^$2＋/) onto the RNA substrate in solution causes change and stabilization of the RNA stem-loop structure, and only the substrate RNA with a rigid stem-loop structure in the essential region can be accurately cleaved by the LRV1-4 viral capsid protein.

• Clinical and Experimental Reproductive Medicine
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• 제22권2호
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• pp.191-201
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• 1995

Transcriptional activation of the embryonic genome initiates at 2-cell stage in mouse embryo and is characterized by the synthesis of TRC which is restricted to 2-cell stage. To investigate the roles of various protein kinases on the embryonic gene activation, the effects of protein kinase inhibitors on in vitro development and protein synthetic profiles of the early mouse embryos were examinded. None of ${\alpna}-amanitin$ which is a mRNA synthetic inhibitor, H8 which is a PKA inhibitor, and H7 which is a PKC inhibitor, affected on first cleavage of mouse 1-cell embryos in vitro. However, all of these drugs inhibited the second cleavage. When the drugs were removed following treatment for 6 hours, H8 or H7 treatment showed little inhibition on subsequent development of 1-cell embryos to 2-cell stage or further. In contrast, ${\alpna}-amanitin$ irreversibly inhibited the development of 1-cell embryos to 2-cell stage following removal of the drug. Genistein, a TPK inhibitor, inhibited both the first cleavage of 1-cell embryos and the second cleavage of 2-cell embryos, suggesting that TPK activity may be important during the early cleavages. All of the above four drugs inhibited TRC synthesis as shown by the fluorographic analysis of $[^{35}S]-Met$ labeled protein profiles. When late 1-cell embryos were treated with H7 and analyzed synthetic patterns of $[^{35}S]-Met$ labeled protein, the quantitative differences of protein synthesis on SDS-PAGE appeared on 77 kD and 33 kD region at $32{\sim}38$ hours post hCG. From these studies, transcriptional activation of embryonic genome is not essenting to the mouse 1-cell embryos to develop to 2-cell stage. Hawever, TPK activity is reguisite for both the first cleavage and second cleavage. Similarly, both PKC and PKA activities are required for the second cleavage of mouse embryos, but not for the first cleavage.

• 생명과학회지
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• 제29권10호
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• pp.1080-1085
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• 2019

본 연구에서는 연(Nelumbo nucifera)의 잎(leaf, NL), 자육(seed, NS), 자방(seedpod, NSP)의 에탄올 추출물을 제조하고 이들의 암세포 항 성장 활성과 세포사멸 활성을 연구하였다. 추출물 NL, NS, NSP는 농도의존적으로 세포 생존율을 감소시켰을 뿐 만 아니라 항암 유전자인 NAG-1 유전자와 단백질의 발현을 증가시켰다. 또한, NL은 NAG-1 단백질의 발현과 PARP cleavage를 시간 의존적으로 증가시켰다. PARP cleavage는 NAG-1 siRNA의 transfection에 의해 부분적으로 감소하였으며, 이러한 결과는 NAG-1이 NL에 의해 유도되는 apoptosis에 기여하는 유전자 중의 하나라는 것을 나타낸다. 그리고, 연근 유래의 순수물질인 neferine도 농도의존적으로 HCT116 세포 생존율을 감소시켰으며, NAG-1 단백질의 발현과 PARP cleavage를 농도의존적, 시간의존적으로 증가시켰다. Neferine에 의해 유도된 PARP cleavage는 NAG-1 siRNA의 transfection에 의해 부분적으로 회복되는 것을 확인하였으며, 이러한 결과는 NAG-1 단백질이 neferine에 의해 유도되는 apoptosis에도 기여하는 유전자 중의 하나라는 것을 시사한다. 종합적으로 본 연구 결과는 연근 부위별 추출물과 연근유래 순수물질인 neferine에 의한 암세포 항 성장 활성과 세포사멸 활성의 분자 생물학적 기전을 이해하는데 도움을 줄 것으로 생각된다.

• Bulletin of the Korean Chemical Society
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• 제23권9호
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• pp.1185-1186
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• 2002

• Bulletin of the Korean Chemical Society
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• 제25권3호
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• pp.403-406
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• 2004

• Bulletin of the Korean Chemical Society
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• 제29권2호
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• pp.301-302
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• 2008

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1467-1468
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• 2010