• Journal of Microbiology
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• 제44권6호
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• pp.655-659
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• 2006

Phylogenetic studies of nef, pol, and env gene sequences of HIV-1 isolated from Koreans suggested the presence of a Korean clade in which Korean sequences are clustered to the exclusion of foreign sequences. We attempted to identify and characterize the Korean clade using all vif gene sequences isolated from Koreans registered in the NCBI GenBank database (n = 233). Most (77 %) of the Korean isolates belonged to the Korean clade as a large subcluster in subtype B, designated the Korean clade subtype B ($K_{C}B$). $K_{C}B$ sequences were relatively homogenous compared to Korean subtype B sequences that did not belong to the $K_{C}B$ (non-Korean clade subtype B; $NK_{C}B$). Comparison of amino acid frequencies of $K_{C}B$ and $NK_{C}B$ sequences revealed several positions where the amino acid frequencies were significantly different. These amino acid residues were critical in separating $K_{C}B$ from $NK_{C}B$ or from foreign sequences, since substitution of these amino acids in $K_{C}B$ with the $NK_{C}B$ amino acids relocated the $K_{C}B$ sequences to $NK_{C}B$, and vice versa. Further analyses of $K_{C}B$ will help us to understand the origin and evolutionary history of $K_{C}B$.

• Toxicological Research
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• 제17권
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• pp.157-166
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• 2001

Almost all currently available retroviral vectors based on murine leukemia virus (MLV) contain one or more viral coding sequences. Because these sequences are also present in the packaging genome, it has been suggested that homologous recombination may occur between the same nucleotide sequence in the packaging genome and the vector, resulting in the production of replication competent retrovirus (RCR). Up until now, it has been difficult to completely remove viral coding sequences since some were thought to be involved in the optimum function of the retroviral vector. For example, the gag coding sequence present in almost all available retroviral vectors has been believed to be necessary for efficient viral packaging, while the pol coding sequence present in the highly efficient vector MFG has been thought to be involved in achieving the high levels of gene expression. However, we have now developed a series of retroviral vectors that are absent of any retroviral coding sequences but produce even higher levels of gene expression without compromising viral titer. In these vectors, the intron and exon sequences from heterologous cellular or viral genes are present. When compared to the well known MLV-based vectors, some of these newly developed vectors have been shown to produce significantly higher levels of gene expression for a longer period. In an experimental system that can maximize the production of RCR, our newly constructed vectors produced an absence of RCR. These vectors should prove to be safer than other currently available retroviral vectors containing one or more viral coding sequences.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2000년도 추계 학술대회
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• pp.31-50
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• 2000

Almost all currently available retroviral vectors based on murine leukemia virus (MLV) contain one or more viral coding sequences Because these sequences are also present in the packaging genome, it has been suggested that homologous recombination may occur between the same nucleotide sequence in the packaging genome and the vector, resulting in the production of replication competent retrovirus (RCR). Up until now, it has been difficult to completely remove viral coding sequences since some were thought to be involved in the optimum function of the retroviral vector. For example, the gag coding sequence present in almost all available retroviral vectors has been believed to be necessary for efficient viral packaging, while the pol coding sequence present in the highly efficient vector MFG has been thought to be involved in achieving the high levels of gene e(pression. However, we have now developed a series of reroviral vectors that are absent of any retroviral coding sequences but produce even higher levels of gene expression without compromising viral titer. In these vectors the intron and exon sequences from heterologous cellular or viral genes are present, When compared to the well blown MLV-based vectors, some of these newly developed vectors have been shown to produce significantly higher levels of gene expression for a longer period. In an experimental system that can maximize the production of RCR, our newly constructed vectors produced an absence of RCR. These vectors should prove to be safer than other currently available retroviral vectors containing one or more viral coding sequences

• 대한바이러스학회지
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• 제27권2호
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• pp.239-255
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• 1997

전염성 췌장괴저바이러스 (Infectious pancreatic necrosis virus) DRT 주의 VP1유전자를 대 장균 발현운반체와 Baculovirus에 삽입하여 대장균과 진핵세로에서 VP1단백질의 발현을 연구하였다. 재조합체 pMal-pol 클론 [7]에서 2.7 Kb 단편인 VP1 유전자를 제한효소 XbaI으로 절단하여 Baculovirus 운반체인 pBacPAK9에 클로닝하여 pBacVP1이라 명명하였다. 이 pBacVP1에 클로닝된 VP1유전자를 제한효소 SacI과 PstI으로 절단하여 대장균 발현 운반체인 pQE-30에 클로닝하여 pQEVP1이라 명명하였다. 또한 VP1 단백질의 C-말단에 6개의 히스티딘 $6{\times}His$이 붙어 있는 단백질을 만들기 위하여, pQEVP1 클론의 His부위를 EcoRI으로 절단하고, 또한 pBacVP1을 EcoRI으로 절단하여 생긴 부위에His-EcoRI DNA 단편을 교체시켜 재클로닝하여 pBacHis-VP1을 만들었다. pBacHis-VP1 DNA와 Bsu36I로 처리된 LacZ-Hyphantria cunea nuclear polyhedrosis virus (LacZ-HcNPV)를 함께 lipofectin을 이용하여 곤충세포 (Spodoptera frugiperda cell)에 동시 감염을 시켜서 재조합 바이러스를 선발하여, VP1-HcNPV-1이라 명명하였다. pQEVP1 클론은 6개의 히스티딘 단편이 부착된 VP1단백질을 Ni-NTA resin 크로마토그래피법으로 정제하여 SDS-PAGE와 Western blot으로 확인하였고, 단백질의 활성과 구조에 영향을 주지 않는 6개의 히스티딘 단편 ($6\;{\times}\;His$)이 부착된 94 kDa의 VP1단백질을 정제할 수 있었다. 또한 재조합 바이러스에 감염된 곤충세포에서 VP1 단백질이 발현된 것을 전기영동과 Western blot으로 검색을 한 결과 95 kDa VP1 단백질이 발현이 되었음을 확인하였다.

• 미생물학회지
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• 제29권2호
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• pp.75-79
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• 1991

The yeast L-A virus (4.6 kb dsRNA genome) encodes the major coat protein and a "gag-pol" fusion minor coat protein that separately encapsidate itself and $M_{1}$, a 1.8 kb dsRNA satellite virus encoding a secreted protein toxin (the killer toxin). The teast chromosomal SKI genes prevent viral cytopathology by lowering the virus copy number. Thus, $ski^{-}$ mutants are ts and cs for growth. We transformed a ski2-2 virus-infested mutant with a yeast bank in a high copy cloning vector and selected the rare healthy transformants for analysis. One type of transformant segregated M-O L-A-O cells with high frequency. Elimination of the DNA clone from the ski2-2 strain eliminated this phinotype and introduction of the DNA clone recovered from such transformants into the parent ski2-2 strain, or into ski3 or ski6 mutants gave the same phenotype. This killer-curing phenotype was due to the curing of the helper L-A dsRNA virus. The 6.5 kb insert only had this activity when carried on a high copy vector and in $ski^{-}$ cells (not in $SKI^{+}$ cells). This 6.5 kb insert acts as a mutagen on L-A dsRNA producing a high rate of deletion mutations.mutations.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2002년도 Molecular and Cellular Response to Toxic Substances
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• pp.199-200
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• 2002

GX-12 is a naked DNA vaccine developed by research team of Dong-A Pharmaceutical Company, Green Cross Company and Genexine for the treatment of HIV infection. It consists of four separate plasmids (pGX10-GE HX, pGX10-dpol JR, pGX10-VN/TV JR, pGX10-hIL-12m), which were constructed by inserting the HIV-1 gag-env, pol, regulatory genes and a human IL-12 mutant gene into pGX10 plasmid vectors.(omitted)

• 미생물학회지
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• 제21권2호
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• pp.61-70
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• 1983

Synchronized cat kidney cells chronically infected with feline leukemia virus (FeLV) were used to study virus production, the synthesis of group specific antigen (gag) and envelope (env) proteins, the expression of env protein on the cell surface during the cell cycle, and the stability of viral RNA. As detecting method, we developed the radioimmunoassay (RIA) system using beta-emission of $^{131}I$ and demonstrated the validity of this system by comparison with routine RIA system using gamma-emission of $^{125}I$. The produced virus was analysed by developed RIA interval was determined by measuring reverse transcriptase activity. The results show that infected cells produce the complete virus particle containing products of gag, env and pol genes of FeLV, and maximum virus production occurs during mitosis of synchronized cells. Labeling of the cell surface of synchronized cells with $^{131}I$ shows that the amount of $gp70^{env}$ on the cell surface parallels cellular gorwth. Therefore, the cell cycle-dependent release of virus is not petition RIA of synchronized cells with $^{131}I$ labeled viral proteins synthesis during the cell cycle. The rate of synthesis of gag protein shows three peaks, corresponding to the $G_1,\;late\;S\;and\;late\;G_2$ phases of cell cycle. But the rate of synthesis of env protein dose not change, suggesting that in these cells the synthesis of these two gene products in controlled seperately. In Actionomycin D treated cells, the synthesis of viral proteins decreased sharply from 8 hours after treatment, and the late S and $G_2$ peaks of gag protein synthesis were disappeared. This shows the stability of viral RNA for about 6 hours in the absence of continuing viral RNA synthesis.

• 농업과학연구
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• 제38권1호
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• pp.45-50
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• 2011

This study was conducted to investigate the farm situation about bovine leukemia virus(BLV) infection that greatly influence productivity in dairy cattle and compare the accuracy of diagnosis for BLV infection between PCR and ELISA techniques. Blood samples of 193 heads from 5 herds in Chungnam and Chungbuk area were used to analyze BLV gene and serum, and the results were obtained as follows. The amplified BLV gene in dairy cattle by PCR technique resulted in 226 bp, 596 bp and 434 bp, respectively, for gag, pol and env, which were well amplified. The infection rates of BLV virus diagnosed by PCR and ELISA techniques ranged from 80.55 to 100% and from 22.22 to 86.95%, respectively, and the infection rates among 5 herds were significantly different in both methods (P<0.05). Further, the average infection rates of 5 herds were 87.05 and 63.21%, respectively, for PCR and ELISA techniques. Kappa statistics for examining consistency of diagnosis by PCR and ELISA techniques showed 0.246, which represents low consistency. Consequently, PCR based BLV technique was considered as a corrective measure for diagnosis of BLV infection in Holstein dairy cattle.

• Reproductive and Developmental Biology
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• 제30권3호
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• pp.181-187
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• 2006

최근 돼지의 장기를 사람에게 이식하는 이종간 장기 이식에 관한 연구가 급속히 발전되고 있다. 그러나 돼지의 장기를 이식할 경우 가장 큰 문제점 중의 하나는 돼지 genome 내에 존재하는 내인성 레트로바이러스(porcine endogenous retrovirus; PERV)가 인간에게 그대로 전이될 수 있다는 것이다. 이에 대한 대안으로 최근 활발히 연구되고 있는 RNA 간섭을 통한 PERV RNA의 발현을 최대한 억제하는 방법이 제안되고 있는데, RNA 간섭(RNA interference)은 double-standard RNA(dsRNA)가 상보적인 표적 mRNA를 분해하여 결과적으로 표적 단백질의 발현을 특이적으로 억제하는 현상을 의미한다. 본 연구에서는 PERV에 대한 RNA 간섭 현상을 일으키는 shRNA 유전자를 레트로바이러스 벡터를 이용하여 돼지세포에 RNA)가 상보적인 표적 mRNA를 분해하여 결과적으로 표적 단백질의 발현을 특이적으로 억제하는 현상을 의미하다. 도입한 후 PERV의 발현율 감소 여부를 조사하였다. 그 결과, gag-pol 유전자와 env 유전자 발현은 각각 대조군 세포의 4%와 10% 정도로 억제되었다. 한편, virus 입자의 생산에서 gag-pol 유전자는 대조군 세포에 비해 300배 이상 억제되었으며, env 유전자에서는 20만 배 이상 억제되었다. 이상의 결과를 미루어 볼 때 형질 전환 돼지를 이용한 이종 장기 이식에 있어서 RNA 간섭 현상을 이용한 PERV의 발현을 억제하는 시도는 생물학적안전성을 크게 증가시킬 수 있을 것으로 사료된다.

• 대한바이러스학회지
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• 제29권2호
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• pp.107-118
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• 1999

To characterize the molecular nature of human immunodeficiency virus (HIV)-1, we determined the full-length HIV-1 sequences from cultured peripheral blood mononuclear cells (PBMC) of a Korean long-term nonprogressor (LTNP). Without antiretroviral therapy, the individual has maintained CD4+ T counts over $500/{\mu}l$ from 1989 to 1999. Plasma viral RNA copy was 992 U/ml in 1998. Culture supernatant showed positive from culture days 9. A series of 9 overlapping PCR products were amplified from cultured PBMC and cloned About 9.2 kb from R of 5' LTR to R of 3' LTR was determined by automated sequencing. The G-to-A hypermutations were shown throughout the entire region. As a result of G to A hypermutations, premature stop codon was found in integrase coding region. Though there was no recombination between subtypes over all genomes, TATA box in both LTRs was TAAAA which is detected in subtype E instead of TATAA in subtype B. And, there were nucleotide GC insertion between $NF-{\kappa}B$ I and Sp1 III, and duplication of $TCF-1{\alpha}$ in LTR. We could not find any deletion of amino acid in Nef, Gag, Pol and Env gene. This study is the first report on molecular nature of full genomes of HIV-1 isolated in Korea.