• Reproductive and Developmental Biology
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• 제32권1호
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• pp.15-20
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• 2008

Pronuclear DNA microinjection has been the most universal method in transgenic animal production but its success rate of transgenesis in mammals are extremely low. To address this long-standing problem, we used retrovirus- and lentivirus-based vectors carrying the enhanced green fluorescent protein (EGFP) gene under the control of ubiquitously active cytomegalovirus (CMV) promoter to deliver transgenes to bovine embryos. The rate of transgenesis was evaluated by counting EGFP positive blastocysts after injection of concentrated virus stock into the perivitelline space of the bovine oocytes in metaphase II. Among two different types of lentivirus vectors derived from FIV (feline immunodeficiency virus) and HIV (human immunodeficiency virus), the former scored the higher gene transfer efficiency; almost 100% of the blastocysts developed from the oocytes infected with FIV-based vector were EGFP positive. As for the vectors derived Com HIV lentivirus, the transgenesis rate of the blastocysts was reduced to 39%.

• 한국가축번식학회지
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• 제25권4호
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• pp.339-347
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• 2001

정자를 매개체로 한 유전자 전이는 형질 전환 동물의 생산을 위한 가능성 있는 간단한 방법이다. 또한 세포질내 정자 주입법에 의한 외래 유전자의 전이에 의한 형질 전환 동물의 생산이 최근에 보고되었다. 본 연구에서는 정자를 EGFP유전자와 공배양한 후 이를 난모세포내에 미세 주입한 다음, 수정란의 발달과 EGFP유전자의 발현을 조사하였다. 돼지 난자에 정자, 세포질막이 파괴된 정자 또는 정자를 주입하였다. 주입 후 수정된 난자는 NCSU23 배양액에서 배반포까지 배양하였으며, 배발생율과 EGFP 유전자의 발현을 연구하였다. 정자를 미세 주입한 결과 난할율은 67.0%로 정자두부를 미세주입한 난할율인 59.7%보다 높았고, 수정란의 EGFP 유전자 발현율은 각각 42.1와 20.0%로서 전자가 유의하게 높았다. 세포질막을 파괴하기 위해 다른 방법들로 정자를 처리하여 주입하였을 시 구정란의 배발생율에 영향을 주지 않았다 정자, 세포막이 파괴된 정자를 주입하여 배반포 발생율을 조사한 결과, 15.0과 14.2%로서 유의차가 없었다. 동결융해하거나 Triton X-100으로 처리한 정자를 주입하여, EGFP 발현율을 조사한 결과, 동결융해 정자를 사용했을 때의 성적이 38.4%로 타군의 성적인 22.4%에 비해 유의하게 높았다. 미세 주입에 앞서 정자는 EGFP 유전자의 0.01 ng/${\mu}\ell$ 부터 1 ng/${\mu}\ell$까지의 여러 농도로 배양되었다. 그러나 난할율을 조사한 결과 EGFP 유전자의 농도 차이에 따른 유의차가 없었다. 정자 배양액에 첨가된 EGFP 유전자의 농도가 0.1 ng/$m\ell$일 때 EGFP 발현율은 37.4%로서 가장 높은 결과를 보였다. 따라서 본 연구의 결과에 의하면 세포질막을 제거한 정자에 외래 유전자가 묻게 되며, 이 정자는 외래유전자를 수정란내로 옮겨 매개체로서의 역할이 가능할 것으로 생각된다.

• Molecules and Cells
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• 제19권1호
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• pp.23-30
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• 2005

Spinocerebellar ataxia type 1 (SCA1) is an autosomal-dominant neurodegenerative disorder caused by expansion of the polyglutamine tract in the SCA1 gene product, ataxin-1. Using d2EGFP, a short-lived enhanced green fluorescent protein, we investigated whether polyglutamine-expanded ataxin-1 affects the function of the proteasome, a cellular multicatalytic protease that degrades most misfolded proteins and regulatory proteins. In Western blot analysis and immunofluorescence experiments, d2EGFP was less degraded in HEK 293T cells transfected with ataxin-1(82Q) than in cells transfected with lacZ or empty vector controls. To test whether the stability of the d2EGFP protein was due to aggregation of ataxin-1, we constructed a plasmid carrying $ataxin-1-{\Delta}114$, lacking the self-association region (SAR), and examined degradation of the d2EGFP. Both the level of $ataxin-1-{\Delta}114$ aggregates and the amount of d2EGFP were drastically reduced in cells containing $ataxin-1-{\Delta}114$. Furthermore, d2EGFP localization experiments showed that polyglutamine-expanded ataxin-1 inhibited the general function of the proteasome activity. Taken together, these results demonstrate that polyglutamine-expanded ataxin-1 decreases the activity of the proteasome, implying that a disturbance in the ubiquitin-proteasome pathway is directly involved in the development of spinocerebellar ataxia type1.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2002년도 춘계학술발표대회 발표논문초록집
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• pp.91-91
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• 2002

There are many methods to introduce exogenous DNA into embryo for the purpose of producing transgenic animals. Exogenous gene can be integrated into oocyte as a form of sperm vector. In this study, sperm was used as a vector for transgene that is enhanced green fluorescent protein (EGFP). The objective of this study was to investigate the expression of exogenous gene in bovine embryos after injection of spermatozoa cocultured with EGFP fragment. Spermatozoa were plunged into liquid nitrogen and thawed several times or shaked in 0.2% Triton X-100 to remove sperm membrane which followed by DTT treatment. (omitted)

• Fisheries and Aquatic Sciences
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• 제13권1호
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• pp.56-62
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• 2010

To determine whether long double-stranded RNA (dsRNA) induces RNA interference and type I interferon (IFN) responses in fish, long dsRNAs encoding enhanced green fluorescent protein (EGFP), GFPuv, and polyinosinic-polycytidylic acid sequences were co-injected with an EGFP expressing plasmid, into rock bream (Oplegnathus fasciatus). We investigated the EGFP mRNA and protein levels, and the transcriptional responses of dsRNA-dependent protein kinase and Mx1 genes. Long dsRNAs were strong inducers of a type I IFN response in rock bream, resulting in nonspecific suppression of exogenous gene expression. Furthermore, sequence-specific knockdown of exogenous gene expression at the mRNA level was detected at an early phase (24 h). These results suggested that long dsRNA may inhibit exogenous gene expression through an early mRNA interference response and a later type I IFN response in fish.

• 한국가축번식학회지
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• 제24권4호
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• pp.439-449
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• 2000

본 연구에서는 정자와 외래유전자인 EGFP 유전자를 공배양한 후 정자직접 주입술로 난자를 수정시켜 EGFP 유전자의 발현을 조사하였다. 정자는 외래유전자의 도입이 용이하도록 동결융해, 0.03% Tween-20과 0.02%의 Triton X-100의 처리를 통하여 정자두부의 원형질막을 제거하여 공시하였다. 수정된 난자는 소 난관상피세포가 포함된 CR1aa 배양액에서 공배양을 통하여 체외발달시켰으며, 난자의 발달에 따라 EGFP 유전자의 발현을 형광 현미경 하에서 조사하였다. 원형질막이 제거된 정자로부터 수정란의 정상수정을 확인하기 위하여 18시간째 2PN 2PB를 조사한 결과, 발생율은 각각 DTT 처리구 44.6%, DTT와 Twen-20 처리구 48.4%, DTT와 동결융해 처리구 44.4%, 그리고 DTT와 Triton X-100 처리구 42.9%였다. 수정란의 초기 배 분할율은 DTT 처리구 49.1 %, DTT와 Tween-20 처리구 58.5%, DTT와 동결융해 처리구 43.9% 그리고 DTT와 Triton X-100 처리구 48.4%였으며, 배반포 형성율은 DTT 처리구 10.2%, DTT와 Tween-20 처리구 13.0%, DTT와 동결융해 처리구 6.8% 그리고 DTT와 Triton X-100 처리구 6.5%였다. 이들 발달된 수정란 중 도입된 EGFP 유전자의 발현율은 DTT 처리구 3.8%, DTT와 Tween-20 처리구 11.1%, DTT와 동결융해 처리구 13.8% 그리고 DTT와 Triton X-100 처리구 8.9%로 나타났으며, 대부분의 발현은 모자이크 형태로 관찰되었다. 따라서 본 연구의 결과에 의하면 소에서 원형질막을 제거한 정자와 외래유전자의 공배양과 이 정자의 난자내 직접도입법에 의해 외래유전자를 가진 형질전환 소 수정란과 형질전환 소 생산이 가능할 것으로 생각된다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권11호
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• pp.1529-1540
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• 2011

Silencing of a specific gene using RNAi (RNA interference) is a valuable tool for functional analysis of a target gene. However, information on RNAi for analysis of gene function in farm animals is relatively nil. In the present study, we have validated the interfering effects of siRNA (small interfering RNA) using both quantitative and qualitative gene silencing in buffalo granulosa cells. Qualitative gene knockdown was validated using a fluorescent vector, enhanced green fluorescence protein (EGFP) and fluorescently labeled siRNA (Cy3) duplex. While quantitatively, siRNA targeted against the luciferase and CYP19 mRNA was used to validate the technique. CYP19 gene, a candidate fertility gene, was selected as a model to demonstrate the technique optimization. However, to sustain the expression of CYP19 gene in culture conditions using serum is difficult because granulosa cells have the tendency to luteinize in presence of serum. Therefore, serum free culture conditions were optimized for transfection and were found to be more suitable for the maintenance of CYP19 gene transcripts in comparison to culture conditions with serum. Decline in fluorescence intensity of green fluorescent protein (EGFP) was observed following co-transfection with plasmid generating siRNA targeted against EGFP gene. Quantitative decrease in luminescence was seen when co-transfected with siRNA against the luciferase gene. A significant suppressive effect on the mRNA levels of CYP19 gene at 100 nM siRNA concentration was observed. Also, measurement of estradiol levels using ELISA (enzyme-linked immunosorbent assay) showed a significant decline in comparison to control. In conclusion, the present study validated gene silencing using RNAi in cultured buffalo granulosa cells which can be used as an effective tool for functional analysis of target genes.

• Journal of Microbiology and Biotechnology
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• 제25권3호
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• pp.386-392
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• 2015

A novel recombinant bacmid, bEasyBm, that enables the easy and fast generation of pure recombinant baculovirus without any purification step was constructed. In bEasyBm, attR recombination sites were introduced to facilitate the generation of a recombinant viral genome by in vitro transposition. Moreover, the extracellular RNase gene from Bacillus amyloliquefaciens, barnase, was expressed under the control of the Cotesia plutellae bracovirus early promoter to negatively select against the nonrecombinant background. The bEasyBm bacmid could only replicate in host insect cells when the barnase gene was replaced with the gene of interest by in vitro transposition. When bEasyBm was transposed with pDualBac-EGFP, the resulting recombinant virus, EasyBm-EGFP, showed high levels of EGFP expression efficiency compared with that of non-purified recombinant virus BmGOZA-EGFP, which was constructed using the bBmGOZA system. In addition, nonrecombinant backgrounds were not detected in unpurified EasyBm-EGFP stocks. Based on these results, a high-throughput system for the generation of multiple recombinant viruses at a time was established.

• 한국가축번식학회지
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• 제24권4호
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• pp.429-437
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• 2000

본 연구는 retrovirus vector system 에 의해서 EPO와 EGFP 유전자가 전이된 소 태아세포를 이용하여 핵치환된 소 난자에서의 이들 유전자의 성공적인 도입을 조사하였다. Non-starved 소 태아세포는 탈핵된 소 난자의 위란강내로 주입되었다. 소 태아 세포와 난자는 세포간 전기자극에 의해 융합시켰으며, 이후 calcium ionophore와 6-dimethylaminopurine를 이용하여 난활성을 유도하였다. 핵치환에 의해 재구성된 난자는 8일 동안 CRlaa 배양액에서 소 난관상피세포와 함께 공배양하였다. 핵치환에 의해 재구성된 187개와 210(EPO, EGFP)개의 소 난자 중에서, 149개와 158(EPO : 80.0%, EGFP : 75.2%)개의 난자가 분할되었고, 이들 분할된 난자 중 36개와 35(EPO : 24.2%, EGFP : 22.2%)개의 난자가 배반포까지 발달하였다. 이들 배반포에서, EPO 유전자는 PCR에 의해 36개의 모든 난자에서 삽입을 확인하였고, EGFP 유전자의 발현은 형광현미경 하에서 35개의 모든 난자에서 확인하였다. 이 결과는 외래유전자가 삽입된 소 태아 세포를 이용하여 핵치환된 난자는 배반포까지 성공적으로 발달할 수 있다는 것을 나타낸다. 더우기, 이러한 방법은 효율적인 형칠전환 소를 생산하는데 이용될 수 있으리라 사료된다.

• BMB Reports
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• 제40권4호
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• pp.547-553
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• 2007

Many motifs along the 1.2 kb myostatin promoter (MSTNpro) in sheep have been found by the MatInspecter program in our recent study. To further verify the role of the motifs and better understand the transcriptional regulation mechanism of the myostatin gene in sheep, the reporter gene EGFP (enhanced green fluorescent protein) was selected and the wild-type (W) vector MSTNPro$^W$-EGFP or motif-mutational (M) vector MSTNPro$^M$-EGFP were constructed. The transcriptional regulation activities were analyzed by detecting the fluorescence strength of EGFP in C2C12 myoblasts transfected with the vectors. The results showed that E-box (E) 3, E4, E5 and E7, particularly E3, E5 and E7, had important effects on the activity of the 1.2 kb sheep myostatin promoter. In addition, we also detected several other important motifs such as MTBF (muscle-specific Mt binding factor), MEF2 (myocyte enhancer factor 2), GRE (glucocorticoid response elements) and PRE (progesterone response elements) along the sheep myostatin promoter by the mutational analysis.