• Parasites, Hosts and Diseases
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• 제55권6호
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• pp.643-652
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• 2017

Calreticulin (CALR), a multifunctional protein thoroughly researched in mammals, comprises N-, P-, and C-domain and has roles in calcium homeostasis, chaperoning, clearance of apoptotic cells, cell adhesion, and also angiogenesis. In this study, the spatial and temporal expression patterns of the Opisthorchis viverrini CALR gene were analyzed, and calcium-binding and chaperoning properties of recombinant O. viverrini CALR (OvCALR) investigated. OvCALR mRNA was detected from the newly excysted juvenile to the mature parasite by RT-PCR while specific antibodies showed a wide distribution of the protein. OvCALR was localized in tegumental cell bodies, testes, ovary, eggs, Mehlis' gland, prostate gland, and vitelline cells of the mature parasite. Recombinant OvCALR showed an in vitro suppressive effect on the thermal aggregation of citrate synthase. The recombinant OvCALR C-domain showed a mobility shift in native gel electrophoresis in the presence of calcium. The results imply that OvCALR has comparable function to the mammalian homolog as a calcium-binding molecular chaperone. Inferred from the observed strong immunostaining of the reproductive tissues, OvCALR should be important for reproduction and might be an interesting target to disrupt parasite fecundity. Transacetylase activity of OvCALR as reported for calreticulin of Haemonchus contortus could not be observed.

• Toxicological Research
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• 제19권2호
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• pp.91-98
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• 2003

Alkylating agents form alkylated base adducts in the DNA and cause DNA lesions leading to cell killing. In this study, we investigated the mechanism of apoptosis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in PC-3 and DU145 human prostate carcinoma cell lines. MNNG treatment resulted in the inhibition of cell proliferation in a concentration-dependent manner to a similar extent in both cell lines. This anti-proliferative effect of PC-3 and DU145 cells by MNNG was associated with morphological changed such as membrane shrinking, cell rounding up and formation of apoptotic bodies. MNNG treatment also induced a proteolytic cleavage of specific target proteins such as poly(ADP-ribose) polymerase (PARP) and $\beta$-catenin proteins in DU145 cells but in PC-3 cells. Furthermore, we observed an increase of proapoptotic protein Bax family expression and a decrease of antiapoptotic protein Bcl-2 family by MNNG treatment in a concentration-dependent manner MNNG also induced a proteolytic activation of caspase-3 and -9, which is believed to play a central role in the apoptotic signaling pathway.

• Journal of Microbiology and Biotechnology
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• 제23권9호
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• pp.1197-1205
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• 2013

Urokinase (uPA) and its receptor (uPAR) play an important role in tumor growth and metastasis. Targeting the excessive activation of this system as well as the proliferation of the tumor vascular endothelial cell would be expected to prevent tumor neovasculature and halt the tumor development. In this regard, the amino-terminal fragment (ATF) of urokinase has been confirmed as effective to inhibit the proliferation, migration, and invasiveness of cancer cells via interrupting the interaction of uPA and uPAR. Previous studies indicated that ATF expressed in Escherichia coli was mainly contained in inclusion bodies and also lacked posttranslational modifications. In this study, the biologically active and soluble ATF was cloned and expressed in Pichia pastoris. The recombinant protein was purified to be homogenous and confirmed to be biologically active. The yield of the active ATF was about 30 mg/l of the P. pastoris culture medium. The recombinant ATF (rATF) could efficiently inhibit angiogenesis, endothelial cell migration, and tumor cell invasion in vitro. Furthermore, it could inhibit in vivo xenograft tumor growth and prolong the survival of tumor-bearing mice significantly by competing with uPA for binding to cell surfaces. Therefore, P. pastoris is a highly efficient and cost-effective expression system for large-scale production of biologically active rATFs for potential therapeutic application.

• International Journal of Oral Biology
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• 제37권4호
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• pp.161-166
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• 2012

The deleted in colorectal cancer (DCC) protein mediates attractant responses to netrin during axonogenesis. In the rat trigeminal ganglia (TG), axons must extend toward and grow into the trigeminal nerve to innervate target tissues such as dental pulp. Our present study aimed to investigate the expression of DCC in the TG. Four developmental timepoints were assessed in the experiments: postnatal days 0, 7 and 10 and adulthood. RT-PCR and western blotting revealed that the expression of DCC mRNA and protein does not significantly change throughout development. Immunohistochemistry demonstrated that DCC expression in the TG was detectable in the perikarya region of the ganglion cells during development. Nerve injury at 3 and 5 days after the mandibular nerve had been cut did not induce altered expression of DCC mRNA in the TG. Moreover, DCC-positive cell bodies also showed similar immunoreactive patterns after a nerve cut injury. The results of this study suggest that DCC constitutively participates in an axonogenesis attractant in ways other than expression regulation.

• 대한세포병리학회지
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• 제10권1호
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• pp.55-60
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• 1999

Schwannoma is a benign encapsulated nerve sheath tumor and is histologically characterized by a mixture of Antoni type A and B tissue. A preoperative diagnosis of schwannoma by fine needle aspiration cytology or by any other means is important a preserve clinically important nerves. Therefore, it is necessary to make a specific cytological diagnosis of nerve sheath tumor. However, there are a few reports regarding cytological features of schwannoma in Korea. We experienced seven cases of solitary schwannoma and here we report their characteristic cytological features with a review of literatures. The characteristic features of schwannoma on cytology were the presence of both Antonl type A and B tissue. The cytologic findings common to all cases of schwannoma generally corresponded to the histologic findings of Antoni type A tissue, consisting of fragments of tightly cohesive fascicles with variable cellularity. Dense fibrillary substances were found, along with palisading nuclei and Verocay bodies. Individual tumor cells consisted of cohesive cells haying spindle or oval nuclei, with pointed ends and Indistinct cell borders. Variation in nuclear size and shape was also present. The Antoni type B consisted of scattered wavy or short spindle cells and some histiocytes and lymphocytes in the abundant myxoid background with formation of microcysts. Immunohistochemistry for S-100 protein revealed a uniformly strong positive reaction and was helpful to make more accurate diagnosis of schwannoma.

• BMB Reports
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• 제41권10호
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• pp.699-704
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• 2008

Embryonic stem (ES) cell-derived cardiomyocytes (ESCMs) must be specifically purified in order to prevent teratoma formation, and this confusing issue has hampered their clinical application. We therefore investigated a technique to generate pure labeled ESCMs for possible use in cardiac repair. We generated transgenic ES cell lines expressing enhanced green fluorescent protein (EGFP) under the transcriptional control of the $\alpha$-cardiac myosin heavy chain ($\alpha$-MHC) promoter. Differentiated EGFP-positive ES cells displayed characteristics of CMs. Furthermore, neuregulin-1 (NRG-1) upregulated the expression of the cardiac-restricted transcription factors Nkx2.5 and GATA-4, as well as differentiated CM factors ($\alpha$-MHC, $\beta$-MHC). Immunohistochemistry demonstrated that NRG-1 increased expression of cardiac-specific troponin T in the beating foci of the embryoid bodies. This work revealed a potential method for specifically labeling and enriching ESCMs by combining genetically-engineered ES cell clones and exogenous growth factor treatment.

• 한국균학회지
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• 제26권4호통권87호
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• pp.502-510
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• 1998

장수버섯 자실체로부터 분리된 강력한 항보체 활성 다당체인 FF-AP1을 정제하고 이것의 화학적 특성을 구명하기 위해 본 실험을 수행한 결과는 다음과 같다. ConA-Sepharose 4B affinity chromatography에 의해 FF-AP1은 $FF-AP1{\alpha}$와 $FF-AP1{\beta}$로 더 분리되었으며 이 중 항보체 활성의 주 유효 다당체인 $FF-AP1{\beta}$는 $10\;{\mu}g/ml$ 농도에서도 약 70%의 항보체 활성도를 나타내었다. $FF-AP1{\beta}$는 약 9.6%의 단백질을 함유한 산성다당체이며 glutamic acid와 aspartic acid의 함량이 상대적으로 다른 아미노산들에 비해 높았다. 이것의 분자량은 gel filtration법에 의해 15,000인 것으로 추정되었고 적외선 분광 분석에서 $890cm^{-1}$ 부근의 소peak를 탐지함으로써 ${\beta}$ glucosidic 결합의 존재를 확인하였다. Gas chromatography에 의한 구성당 조성 분석 결과, 주 구성당이 glucose, mannose, 및 galactose인 galacto-manno-glucan이었고, 소량의 rhamnose, xylose, fucose와 uronic acid도 탐지되었다.

• KSBB Journal
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• 제9권2호
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• pp.165-173
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• 1994

재조합 소성장호르몬을 트립신, S.aureus V8 단백질가수분해효소, CNBr, 그리고 산 가수분해법을 이용하여 단백질 일차구조 분석을 실시하였다. N-말단 분석은 30 잔기까지를 수행하였는데, 대장균 내에서 발현된 소성장호르몬은 E. coli 내 에 존재 하는 methionyl-aminopeptidase에 의해 해독개시인자로 넣어준 N-말단의 Met이 모두 제거된 형태로 나타났으며 아미노산 조성분석 결과 연역된 조성과 유사하게 나타났다. 효소와 화학물질로 절단한 소성장호르몬 조각들을 HPLC로 분리한 후 단백질 서열분석기를 이용하여 아미노산 서열을 분석하였다. 대장균에서 발현된 소성장호르몬은 191개의 아미노산으로 구성된 21,802 Da의 분자량을 갖고 있는 단백질로 나타났다. 여기에서 을 갖고 있는 단백질로 나타났다. 여기에서 얻은 아미노산 서열을 바탕으로 hydropathy plot을 한 결과 N-말단에서는 소수성이 그리고 C-말단에서는 친수성 영역이 나타났다.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1987년도 식물생명공학 심포지움 논문집 Proceedings of Symposia on Plant Biotechnology
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• pp.261-282
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• 1987

Plants store a significant amount of their nitrogen, sulfur and carbon reserves as storage proteins in seed tissues. The major proteins present in rice seeds are the glutelins. Glutelins are initially synthesized at 4-6 days postanthesis and deposited into protein bodies via Golgi apparatus. Based on nucleic acid sequences and Southern blot analysis, the three isolated glutelin genomic clones were representative members of three gene subfamilies each containing 5 to 8 copies. A comparison of DNA sequences displayed by relevant regions of these genomic clones showed that two subfamilies, represented by clones, Gt1 and Gt2, were closely, related and probably evolved by more recent gene duplication events. The 5' flanking and coding sequences of Gt1 and Gt2 displayed at least 87% homolgy. In contrast, Gt3 showed little or no homolgy in the 5' flanking sequences upstream of the putative CAAT boxes and exhibited significant divergence in all other portions of the gene. Conserved sequences in the 5' flanking regions of these genes were identified and discussed in light of their potential regulatory role. The derived primary sequences of all three glutelin genomic clones showed significant homology to the legume 11S storage proteins indicating a common gene origin. A comparison of the derived glutelin primary sequences showed that mutations were clustered in three peptide regions. One peptide region corresponded to the highly rautable hypervariable region of legume peptide region of legume 11S storage proteins, a potential target area for protein modification. Expression studies indicated that glutelin mRNA transcripts are differentially accumulated during endosperm development. Promoterss of Gt2 and Gt3 were functional as they direct transient expression of chloramphenicol acetyltransferase in cultured plant cell.

• Animal Bioscience
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• 제37권2호
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• pp.284-294
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• 2024

Objective: Pork is an important source of animal protein in many countries. Subtle physiochemical changes occur during pork postmortem aging. The changes of apoptosis and autophagy in pork at 6 h to 72 h after slaughter were studied to provide evidence for pork quality. Methods: In this article, morphological changes of postmortem pork was observed through Hematoxylin-eosin staining, apoptotic nuclei were observed by TdT-mediated dUTP nick end labeling assay, protein related to apoptosis and autophagy expressions were tested by western blot and LC3 level were expressed according to immunofluorescence assay. Results: In this study, we found the occurrence of apoptosis in postmortem pork, and the process was characterized by nucleus condensation and fragmentation, formation of apoptotic bodies, increase in apoptosis-related Bax/Bcl-2 levels, and activation of caspases. Autophagy reached its peak between 24 and 48 h after slaughter, accompanied by the formation of autophagosomes on the cell membrane and expression of autophagy-related proteins beclin-1, P62, LC3-I, LC3-II, and ATG5. Conclusion: Obvious apoptosis was observed at 12 h and autophagy reached its peak at 48 h. The present work provides the evidence for the occurrence of apoptosis and autophagy during postmortem aging of pork. In conclusion, the apoptosis and autophagy of muscle cells discovered in this study have important implications for pork in the meat industry.