• Biotechnology and Bioprocess Engineering:BBE
• /
• 제7권2호
• /
• pp.67-75
• /
• 2002

The human complement receptor type 1 (CR 1, C3 b/C4b receptor) is a polymorphic membrane glycoprotein expressed on human erythrocytes, peripheral leukocytes, plasma and renal glomerular podocytes, which consists of transmembrane and cytoplasmic domains with 30 repeating homologous protein domains known as short consensus repeats (SCR). CR1 has been used as an inhibitor for inflammatory and immune system for the past several years. Recently; it is reported that CRl was found to suppress the hyper-acute rejection in xeno-transplantation and can be used to cure autoimmune diseases. A soluble form of CRl, called sCRl, is a recombinant CRl by cleaving the transmembrane domain at C-terminus and has been expressed in Chinese Hamster Ovary (CHO) cells. Several purification methods for sCR1 from CHO cells have been reported, but most of them require complicated steps at high cost. Moreover, such methods are mostly performed under the pH condition apt to denaturing sCR1 and causes sCRl losing its activity. We here report a rapid and efficient method to purify sCR1 from CHO cell. The new method consists of a two-stage of cell culture by cultivating cells in serum medium followed by serum-free medium, and a two-stage of column purification by means of heparin and gel filtration column chromatography. By using this novel method, sCR1 can be purified in a simple and effective way with high yield and purity, furthermore, the purified sCR1 was confirmed to retain its activity to suppress the complement activation in vivo and ex vivo.

• 한국응용곤충학회지
• /
• 제39권3호
• /
• pp.193-197
• /
• 2000

Wolbachia는 몇몇 곤충류에 공생하는 세포내 공생세균으로서 수직 감염되며, 숙주의 세포질 불화합성, 단위생식, 자성화 등을 유도한다. 현재까지 알려진 Wolbachia는 비병원성이지만 돌연변이인 popcorn은 숙주인 초파리(Drosophila melanogaster)에 수직 감염되어 성충의 조직괴사와 조기 사망 등의 병원성을 나타낸다. Popcorn에 감염된 초파리는 알과 유충 발육기간이 연장되고, 번데기 기간은 단축되는 경향을 보이며, 성충의 수명이 단축되었다. 또한 비병원성 Wolbachia에 감염된 경우보다 산란율은 15%, 부화율은 80% 수준으로 감소하였고, 용화율은 67%, 우화율은 65%에 불과하였다. Popcorn과 비병원성 Wolbachia간의 교배에서 감염된 초파리는 모두 산란수의 감소와 차세대 부화율, 용화율, 우화율 등의 감소를 초래하였으며, popcorn에 감염된 초파리의 특성을 나타냈다. Wolbachia에 감염되지 않은 초파리와의 교배에서 popcorn 감염 초파리가 수컷인 경우 Wolbachia가 검출되지는 않았다. 따라서 popcorn은 초파리에서 모체 전염되지만, 세포질 분화합성은 유도하지 않으며, 초파리의 초기발육의 지연, 생식의 저하, 성충수명의 단축을 야기하는 등 병원성을 나타냈다.

• Clinical and Experimental Reproductive Medicine
• /
• 제42권1호
• /
• pp.22-29
• /
• 2015

Objective: Sperm must be properly prepared in in vitro fertilization (IVF)-embryo transfer (ET) programs in order to control the fertilization rate and ensure that embryos are of high quality and have appropriate developmental abilities. The objective of this study was to determine the most optimal sperm preparation method for IVF. Methods: Patients less than 40 years of age who participated in a fresh IVF-ET cycle from November 2012 to March 2013 were included in this study. Poor responders with less than three mature oocytes were excluded. Ham's F-10 medium or sperm-washing medium (SWM) was used in combination with the density-gradient centrifugation/swim-up (DGC-SUP) or SUP methods for sperm preparation. A total of 429 fresh IVF-ET cycles were grouped according to the media and methods used for sperm preparation and retrospectively analyzed (DGC-SUP/Ham's F-10, n=82; DGC-SUP/SWM, n=43; SUP/Ham's F-10, n=181; SUP/SWM, n=123). Results: There were no significant differences among these four groups with respect to the mean age of the female partners, duration of infertility, number of previous IVF cycles, and retrieved oocytes. We determined that both the DGC-SUP and SUP methods for sperm preparation from whole semen, using either Ham's F-10 or SWM media, result in comparable clinical outcomes, including fertilization and pregnancy rates. Conclusion: We suggest that both media and both methods for sperm preparation can be used for selecting high-quality sperm for assistive reproductive technology programs.

• 한국균학회소식:학술대회논문집
• /
• 한국균학회 2015년도 추계학술대회 및 정기총회
• /
• pp.35-35
• /
• 2015

Pleurotus eryngii has recently become a major cultivated mushroom; it uses tetrapolar heterothallism as a part of its reproductive process. Sexual development progresses only when the A and B mating types are compatible. Such mating incompatibility occasionally limits the efficiency of breeding programs in which crossing within loci-shared strains or backcrossing strategies are employed. Therefore, understanding the mating system in edible mushroom fungi will help provide a short cut in the development of new strains. We isolated and identified pheromone and receptor genes in the B3 locus of P. eryngii and performed a functional analysis of the genes in the mating process by transformation. A genomic DNA library was constructed to map the entire mating-type locus. The B3 locus was found to contain four pheromone precursor genes and four receptor genes. Remarkably, receptor PESTE3.3.1 has just 34 amino acid residues in its C-terminal cytoplasmic region; therefore, it seems likely to be a receptor-like gene. Real-time quantitative RT-PCR (real-time qRT-PCR) revealed that most pheromone and receptor genes showed significantly higher expression in monokaryotic cells than dikaryotic cells. The pheromone genes PEphb3.1 and PEphb3.3 and the receptor gene PESTE3.3.1 were transformed into P5 (A3B4). The transformants were mated with a tester strain (A4B4), and the progeny showed clamp connections and a normal fruiting body, which indicates the proposed role of these genes in mating and fruiting processes. This result also confirms that PESTE3.3.1 is a receptor gene. In this study, we identified pheromone and receptor genes in the B3 locus of P. eryngii and found that some of those genes appear to play a role in the mating and fruiting processes. These results might help elucidate the mechanism of fruiting differentiation and improve breeding efficiency.

• 한국동물학회지
• /
• 제33권3호
• /
• pp.365-372
• /
• 1990

Transgenic 양서류를 만들기 위한 연구의 일환으로 bacterial $\beta$-galactosidase 유전자를 cytopalsmic actin promoter에 연결시킨 plasmid를 xenopus 수정란에 미세주입하여 외부 DNA의 발현을 조사하였다. $\beta$-gal DNA를 20nl당 1ng에서 2ng의 농도로 미세주입하는 경우, 이 농도는 배발생에 크게 영향을 미치지 않는 것으로 나타났다. 또한 유전자 산물인 $\beta$-galactosidase는 양서류의 모든 배엽성 세포에서 발현 가능하고, 정상적인 활성을 나타내므로 외부 DNA의 발현여부를 in situ 상태에서 판명할 수 있었다. 주입된 외부 DNA는 낭배기 시기에 최초로 발현되고, 적어도 올챙이 시기까지 유지 및 발현 가능하며, 초기 발생동안 extrachromosomal 상태에서 발현되는 것으로 나타났다. 그러나 발현의 정도는 주입된 개체는 물론 매 실험마다 차이를 보였고, 또한 기질인 X-Gal에 반응하는 부위가 전체 배에 분포하는 겅우는 거의 없으며, 일정 부위에 한정되어 있음이 관찰되었다. 이는 세포막을 통해서 DNA가 다른 할구로 이동하지 못하는 사실에 비추어 미세주입된 DNA가 난할시 각 할구로 균등하게 분포되지 못하고 국부적으로 나뉘어 들어가기 때문인 것으로 사료된다.

• Journal of Plant Biology
• /
• 제35권3호
• /
• pp.219-227
• /
• 1992

지질성 종자(해바라기, 피마자, 잣나무)와 전분성 종자(완두, 옥수수)를 대상으로 배유와 자엽세포내의 저장지질의 형성, 분포 및 구조적 변화 등과 지질가수분해효소의 활성부위 및 세포내 분포양상 등을 세포화학적 방법을 이용하여 조사하였다. 채종후의 지질 및 전분성 종자의 배유와 저장성 자엽세포에는 구형의 단백과립과 지질소구인 스페로솜, 전분과립 등의 저장물질이 널리 분포하였으며 세포내소기관은 드물게 관찰되었다. 활면소포체에서 형성되어 방출된 소포들과 스페로솜의 초기 단계로 여겨지는, 전자밀도가 낮은 막성의 과립들은 염색상이 스페로솜의 그것과 동일하였다. 조면소포체에서 방출된 전자밀도가 높은 과립들은 원형질막의 인접부위에서 관찰되었다. 지질염색반응 결과, 일반적인 미세구조의 염색상과는 상이하게 단백과립내의 단백질보다는 구형의 스페로솜의 전자밀도가 높고 균일함이 확인되어 스페로솜의 주요 구성성분은 지질임을 알 수 있었다. 스페로솜과 활면소포체에서 방출하는 물질을 함유한 소포는 염색상이 동일하였다. 지질가수분해효소는 분해과정이 진행중인 스페로솜의 기질과 막 주변부, 그리고 원형질막 부근에서 강한 활성을 보였다.

• 약학회지
• /
• 제60권3호
• /
• pp.128-134
• /
• 2016

L1 cell adhesion molecule (L1CAM) is a cell surface molecule to initiate a variety of cellular responses through interacting with other cell adhesion molecules in a homophilic or heterophilic manner. Although its expression was found to be upregulated in some tumor cells, including cholangiocarcinomas, and ovarian cancers, and many studies have investigated the role of L1CAM in these cancers, its role in inflammatory responses has been poorly understood. In this study, we explored the role of L1CAM in macrophage-mediated inflammatory responses. L1CAM significantly suppressed the production of nitric oxide (NO), but induced cell proliferation in RAW264.7 cells. L1CAM expression was detectable, but its expression was markedly decreased by lipopolysaccharide (LPS) in RAW264.7 cells. In addition, the expression of pro-inflammatory genes, such as tumor necrosis factor (TNF)-${\alpha}$, cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS) induced by LPS was dramatically suppressed by L1CAM in RAW264.7 cells. L1CAM inhibited the transcriptional activities of NF-${\kappa}B$ and AP-1 while its cytoplasmic domain deletion form, $L1{\Delta}CD$ did not suppressed their activities in RAW264.7 cells. Moreover, L1CAM suppressed nuclear translocation of p65 and p50 as well as c-Jun, c-Fos and p-ATF2 which are transcription factors of NF-${\kappa}B$ and AP-1, respectively. In conclusion, L1CAM suppressed inflammatory responses in macrophages through inhibiting NF-${\kappa}B$ and AP-1 pathways.

• Journal of Plant Biology
• /
• 제38권1호
• /
• pp.55-62
• /
• 1995

벼(Oryza sativa L. cv. Kye Hwa) 성숙종자에서 유도한 배발생 세포(embryogenic cell, EC)의 동위효소 발현양상과 효소활성을 조사하였다. 배발생 캘러스로부터 확립된 EC 현탁배양은 세포가 둥글며 세포질이 충만한 세포들로 이루어졌으나 비배발생 세포(nonembryogenic cell, NEC)의 현탁배양은 크게 신장한 액포화된 세포들로 구성되었다. 이러한 EC와 NEC의 peroxidase, esterase, acid phosphatase 그리고 malate dehydrogenase의 동위효소 양상과 활성도를 분석한 결과 밴드의 수와 특이성 그리고 밴드 활성 등에 현저한 차이를 보여주었으며 또한 이들 동위효소의 효소 활성도 측정 결과 EC에서 훨씬 더 높게 나타났다. NEC에는 나타나지 않은 EC의 특이 밴드와 강한 밴드 활성 그리고 높은 효소 활성 등은 EC의 형태적, 분화능과의 관련성을 내포하고 있다. 이러한 결과들은 이들 효소의 특이 밴드들이 벼에서 EC의 생화학적 표지자로서 사용될 수 있음을 내포하고 있다.

• 한국식물학회:학술대회논문집
• /
• 한국식물학회 1996년도 제10회 식물생명공학심포지움 고등식물 발생생물학의 최근 진보
• /
• pp.48-60
• /
• 1996

We previously identified and characterized a predominantly pollen-expressed gene of Petunia inflata that encodes a receptor-like kinase named PRK1. The extracellular domain of PRK1 contains leucine-rich repeats which have been implicated in protein-protein interactions, and the cytoplasmic domain was found to autophosphorylate on serine and tyrosine. To investigate the function PRK1 in pollen development, we transformed P. inflata plants with a construct containing the promoter of a predominantly pollen-expressed gene of tomato, LAT52, fused to an antisense PRK1 cDNA corresponding to part of the extracellular domain of PRK1, There transgenic plants were found to each produce approximately equal amounts of normal and aborted pollen. Analysis of the inheritance of the transgene inserts in two of the transgenic plants, ASRK-13 and ASRK-20, to their progeny revealed that certain transgene inserts cosegregated with the pollen abortion phenotype. Microscopic examination of the aborted pollen grains showed that their outer wall, the exine, was essentially normal, but that their cytoplasm contained only starch-like granules. Staining of the nuclei of the microspores at different stages of uninucleate stage. However, at subsequent stages half of the microspores completed mitosis and developed into normal binucleate pollen, but the other half initially remained uninucleate, then lost their nucleio. Analysis of the amounts of PRK1 mRNA and the antisense PRK1 transcript suggested that the pollen abortion phenotype most likely resulted from down-regulation of the PRK1 gene by the antisense PRK1 transgene. These results suggest that PRK1 plays an essential role in a signal transduction pathway that mediates post-meiotic development of microspores.

• Animal cells and systems
• /
• 제1권4호
• /
• pp.657-663
• /
• 1997

The CD4 and CDS coreceptors, in conjunction with the T cell receptor (TCR) , make important contributions to the differentiation of thymocytes. They have been shown to be involved in the clonal deletion and positive selection processes during T cell development in thymus. To further analyze the role of CD4 and CDS proteins during T cell differentiation, we have generated transgenic mice constitutively expressing high levels of a native CD4 and a CD4{CDSa hybrid protein. The hybrid protein is composed of CD4 extracellular domain linked to the CD8a transmembrane region and cytoplasmic tail. The transgenes were driven by human beta-actin promoter, and therefore, they were expressed in all tissues examined including thymus, spleen, and lymph nodes. The resulting CD4 and CD4{CD8${\alpha}$transgenic mice were found to express the CD4 and CD4{CD8${\alpha}$ respectively, in developing thymocytes and peripheral T cells. The expression levels of transgenic proteins were 5-10 times higher than that of endogenous CD4 in thymus. However, total surface CD4 expression (CD4 or CD4{CD8${\alpha}$ transgenic protein plus endogenous CD4) of the transgenic mice were main. tained at similar levels compared to control littermates. Surface CD4 expression on CDS T cells, however, was significantly lower than that on cells expressing endogenous CD4. These results suggest that a total avidity between developing thymocytes and thymic stromal cells is impor. tant for differentiation of thymocytes.