검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 73

        21.
        2012.06 구독 인증기관 무료, 개인회원 유료
        We prepared the polyclonal antibody anti-20α-hydroxysteroid dehydrogenase (anti-20α-HSD) against the recombinant full-length protein bovine 20α-HSD in Escherichia coli. The specificity of anti-20α-HSD was demonstrated using Chinese hamster ovary (CHO) cells transfected with recombinant bovine 20α-HSD and bovine placental tissues. According to western blot analysis, anti-20α-HSD specifically recognizes the 37-kDa protein bovine 20α-HSD. The protein is not present in untransfected CHO cells. Anti-20α-HSD also recognizes a specific protein in the ovaries and placenta of other animals. Immunostaining was used to detect expression of bovine 20α-HSD protein in the cultured luteal cells during the estrous cycle later.
        4,000원
        22.
        2012.06 구독 인증기관·개인회원 무료
        Human protein C (hPC) is a regulator of homeostasis, suggesting its potential use as a therapy for many disease states. Protein C is a zymogen of a serine protease that is activated by thrombin. Protein C, also known as autoprothrombin ⅡA and blood coagulation factor ⅪⅤ, is a zymogenic (inactive) protein, the activated form of which plays an important role in regulating blood clotting, inflammation, cell death and maintaining the permeability of blood vessel walls in humans and other animals. hPC is a 62 KD disulfide- linked heterodimer consisting of a 21 KD light chain and a 41 KD heavy chain which circulates as an inactive zymogen in plasma. In this study, we focus on generation of hPC transgenic mice. hPC transgenic mice were produced by using micro-injection method. The hPC cDNA was cloned into pBC1 vector under goat β-casein promoter. One-cell stage embryos microinjected were transferred to 24 recipient mice on day 1 of the estrus cycle. We screened 61 mice by the PCR. Four line transgenic mice were identified and confirmed expression of protein C gene in mammary gland and several organ. We also analyzed the expression of mRNA and protein through the northern blot and western blot in mammary gland of hPC transgenic mice. hPC was localized in the alveolar epithelial cell by immunohistochemistry. Now, we are collecting the milk from the 2 found lines. After then, we are checking the activity of hPC produced from mice milk.
        23.
        2012.06 구독 인증기관·개인회원 무료
        Interferon-tau (IFNT) is regarded, generally, to be the conceptus protein that signals maternal recognition of pregnancy in ruminants. Although the discovery was made over two decades ago, the molecular mechanisms that regulate IFNT expression are not well understood. Previous studies demonstrated that transcription factors, caudal-related homeobox- 2 (CDX2), JUN, ETS2 and a transcriptional coactivator CREB binding protein (CREBBP) positively influenced IFNT gene expression, while OCT4 may exhibit negative regulation. We and others have observed that both CDX2 and OCT4 coexist during early stages of conceptus elongation but as development proceeds, OCT4 expression diminishes. The objective of this study was to evaluate the stimulatory and inhibitory effects of CDX2 and OCT4, respectively, on IFNT gene transcription when evaluated with other transcription factors. Human choriocarcinoma JEG3 cells were co-transfected with an ovine IFNT (-654 base pair)-luciferase reporter (-654-oIFNT-Luc) construct and several transcription factor expression plasmids. When the reporter construct was co-transfected with either CDX2, ETS2 or CJUN, transcription of -654-oIFNT-Luc increased about two-fold compared to -654-oIFNT-Luc alone. When -654-oIFNT-Luc was co-transfected with both c-jun and Ets-2, activity of -654-oIFNT-Luc was increased about four-fold; cotransfection with JUN, ETS2 and CDX2 increased -654-oIFNT-Luc expression 12X, indicating that the stimulatory activity of the transcription factors was additive. OCT4, when cotransfected with -654-oIFNT-Luc, reduced expression of the later about 40% when compared to -654-oIFNT-Luc alone. When co-transfected with JUN and/or ETS2, OCT4 abolished the stimulatory effect of these transcription factors. OCT4 also inhibited the stimulatory activity of CDX2 alone, but not when CDX2 was combined with JUN and/or ETS2. Therefore, when combined with the other transcription factors, CDX2 over the transcriptional inhibitory activity of OCT4. Conversely, when cells were transfected initially with OCT4 (0h) followed by transfection with CDX2, ETS2 and JUN 24 h later, -654-oIFNT-Luc expression was reduced to control (-654-oIFNT-Luc, alone) levels. Not surprisingly, 12S E1A, an inhibitor of transcriptional coactivator CREBBP, reduced stimulation of -654- oIFNT-Luc expression by CDX2, ETS2 and JUN, in combination, by about 40%, indicating that proper transcription complex formation is required for maximum expression. In conclusion, it is suggested that prior to conceptus elongation, pre-existing OCT4 may inhibit IFNT expression, but as elongation proceeds, IFNT expression increases, resulting from incremental increases in CDX2 expression, diminished OCT4 expression, and possibly proper transcription factor complex formation. Key words) Interferon-tau, CDX2, OCT4, transcription
        24.
        2012.06 구독 인증기관·개인회원 무료
        20ɑ-hydroxysteroid dehydrogenase (20ɑ-HSD) enzyme converts progesterone into biological inactive steroid, thus playing a key role in the termination of pregnancy or estrus cycle and allowing parturition and ovulation to occur in most mammalian animals. However, function and regulation of this enzyme has not known well in primate reproductive physiology. We previously demonstrated the expression level and localization of the 20α-HSD in the reproductive tissues of macaque monkeys of pre-ovulation and pre-parturition period. Also, we amplified about 2005 bp 5'-flanking region from placenta genomic DNA and examined methylation pattern and promoter activity. In present study, we focus on the analysis of molecular characterization of the promoter region by using reporter assay systems. We constructed of deleted mutants (— 890 bp; HSF-2), (— 513 bp; XFD), (— 276 bp; Ap-1) and (— 72 bp; Sp-1) and each mutants were cloned into pGL3-basic vector. These deletion mutants were transfected into CHO cells and co-transfected with Sp-1 or Ap-1 transcription factor plasmids. Compared to — 890 bp and 513 bp promoter fragments alone, transcription activity increased when these constructs were co-transfected with Sp-1 and Ap-1 factor. However, for the absence Ap-1 factor binding site in 276 bp fragment activity dramatically decreased in both transfections. Next, we constructed of 306 bp fragment which is including of Ap-1 binding site and nucleotides converted mutants of the Ap-1 factor binding site. In this result, 306 bp fragment's transcription activity was high as wild type. However, the mutant activity which converted Ap-1 site’s all nucleotide was significantly decreased. These findings are confirmed by gel-shift assay examining Ap-1 binding site on the 20 α-HSD gene upstream region and expression of Ap-1 factor was determined by RT-PCR and Western blot in pre-parturition period placenta and CHO-K1 cell line. Our results indicate that Ap-1 site (— 281 → — 274) (5'-TGTCTCAT-3') plays a crucial role for monkey 20 α- HSD gene transcription.
        28.
        2010.12 구독 인증기관 무료, 개인회원 유료
        Erythropoietin (EPO) is a glycoprotein hormone secreted from primarily cells of the peritubular capillary endothelium of the kidney, and is responsible for the regulation of red blood cell production. We constructed and expressed dimeric cDNAs in Chinease hamster ovary (CHO) cells encoding a fusion protein consisting of 2 complete human EPO domains linked by a 2-amino acid linker (Ile-Asp). We described the activity of dimeric hyperglycosylated EPO (dHGEPO) mutants containing additional oligosaccharide chains and characterized the function of glycosylation. No dimeric proteins with mutation at the 105th amino acid were found in the cell medium. Growth and differentiation of the human EPO-dependent leukemiae cell line (F36E) were used to measure cytokine dependency and in vitro bioactivity of dHGEPO proteins. MTT assay at 24 h increased due to the survival of F36E cells. The dHGEPO protein migrated as a broad band with an average molecular mass of 75 kDa. The mutant, dHGEPO, was slightly higher than the wild-type (WT) dimeri-EPO band. Enzymatic N-deglycosylation resulted in the formation of a narrow band with a molecular mass twice of that of of monomeric EPO digested with an N-glycosylation enzyme. Hematocrit values were remarkably increased in all treatment groups. Pharmacokinetic analysis was also affected when 2.5 IU of dHGEPO were intravenously injected into the tails of the mice. The biological activity and half-life of dHGEPO mutants were enhanced as compared to the corresponding items associated the WT dimeric EPO. These results suggest that recombinant dHGEPO may be attractive biological and therapeutic targets.
        4,000원
        29.
        2010.12 구독 인증기관 무료, 개인회원 유료
        During normal early embryonic development in mammals, the global pattern of genomic DNA methylation undergoes marked changes. The level of methylation is high in male and female gametes. Thus, we cloned the cDNA of the porcine DNA methyltransferase 1 (Dnmt1) gene to promote the efficiency of the generation of porcine clones. In this study, porcine Dnmt1 cDNA was sequenced, and Dnmt1 mRNA expression was detected by reverse transcription-polymerase reaction (RT-PCR) in porcine tissues during embryonic development. The porcine Dnmt1 cDNA sequence showed more homology with that of bovine than human, mouse, and rat. The complete sequence of porcine Dnmt1 cDNA was 4,774-bp long and consisted of an open reading frame encoding a protein of 1611 amino acids. The amino acid sequence of porcine DNMT1 showed significant homology with those of bovine (91%), human (88%), rat (76%), and mouse (75%) Dnmt1. The expression of porcine Dnmt1 mRNA was detected during porcine embryogenesis. The mRNA was detected at stages of porcine preimplantation development (1-cell, 2-cell, 4-cell, 8-cell, morula, and blastocyst stages). It was also abundantly expressed in tissues (lung, ovary, kidney and somatic cells). Further investigations are necessary to understand the complex links between methyltransferase 1 and the transcriptional activity in cloned porcine tissues.
        4,000원
        37.
        2010.09 구독 인증기관 무료, 개인회원 유료
        This study was performed to comprehend the plasma proteins expressed specifically during early pregnancy in pregnant or non-pregnant Hanwoo using proteomic analysis technique. Plasma samples (0, 2, 3, 4, 7, and 11 weeks after AI) were obtained from pregnant (P, n=3) or non-pregnant (NP, n=4) Hanwoo, respectively. To evaluate proteins differentially expressed, 2-dimensional electrophoresis (2DE) was conducted. Normalized protein spots were selected for the significant expression variation deviated over two fold in its expression level between two groups. Molecular functions of the proteins were DNA binding, protein binding, hemoglobin binding, ferrochelatase and transporter activity and arylestera, respectively. According to western blotting, haptoglobin was specifically expressed only in NP group during early pregnancy; however, paraoxonase 1 was highly expressed in pregnant group. Based on these results, pregnancy was maintained successfully by the activation of specific plasma proteins associated with immune system and antioxidant regulation during early pregnancy in Hanwoo
        4,000원
        38.
        2010.06 구독 인증기관 무료, 개인회원 유료
        Erythropoietin (EPO), a glycoprotein hormone produced from primarily cells of the peritubular capillary endothelium of the kidney, is responsible for the regulation of red blood cell production. We have been investigating the roles of glycosylation site added in the biosynthesis and function of recombinant protein. In this study, we analyzed by immunohistochemical methods adaptive mechanisms to excessive erythrocytosis in transgenic (tg) mice expressing dimeric human erythropoietin (dHuEPO) gene. Splenomegaly was observed over 11 21 times in the tg mice. The 2,672 candidate spleen‐gderived genes were identified through the microarray analysis method, and decreased genes were higher than increased genes in the spleen. The specific proteins in the increased and decreased genes were analyzed by immunohistochemical methods. Our results demonstrate that problems of abnormal splenomegaly would solve in tg mice overexpressing dHuEPO gene.
        4,000원
        40.
        2010.03 구독 인증기관 무료, 개인회원 유료
        Matrix metalloproteinases (MMP) play important roles in extracellular matrix (ECM) remodeling during ovarian follicular development, oocytes development and ovulation. In an attempt to investigate the effect of MMP activation in development cumulus-oocytes complexes, we examined the localization and expression of MMP, and monitored MMP expression profile. Cumulus-oocytes complexes were collected and matured in vitro for 24 hr, 36 hr and 48 hr. A mRNA expression of MMP-2, MMP-9, TIMP-2 and TIMP-3 was detected in all culture medium regardless of CC, OC and COCs. Activity of MMP-2 in the OC progressively was increased from 24 hr to 48 hr. But MMP-9 was not detected in all culture medium. The localization of MMP-2 was also measured by immunohistochemistry analysis. The MMP-2 and TIMP-2 was detected in cumulus cell and oocyte zone pellucida. Expression of MMP-2 protein in the COCs was progressively increased from 24 hr to 48 hr. However, MMP-9 protein was progressively decreased from 24 hr to 48 hr. And TIMP-2 protein was most highly expressed in the COCs 36 hr. Expression of TIMP-3 protein in the COCs was progressively increased from 24 hr to 48 hr. In conclusion, these results suggest that MMP-2 plays a role in maintaining normal maturation and development by controlling the ECM inhibitor concentration on cumulus cell and oocytes.
        4,000원
        1 2 3 4