9,724 research outputs found
Epigenetic Regulation of the Placental Fusogenic Protein, Syncytin2
No full textSyncytin 2屬於人類內生性反轉錄病毒（human endogenous retrovirus）HERV-FRD之外鞘蛋白，其專一表現在胎盤滋養層細胞中，已知syncytin 2會促進細胞滋養層細胞進行細胞融合，而形成融合滋養層，故syncytin 2在胎盤發育上扮演重要的角色。而過去研究指出，人類胚胎發育過程中，胎盤組織裡的DNA甲基化程度明顯較胚胎本體組織來的低，且最近有報導發現，syncytin家族另一個成員syncytin 1，在胎盤細胞中，syncytin 1之5’-long terminal repeat（5’-LTR）啟動子上DNA甲基化程度非常低，使得syncytin 1能表現於胎盤細胞中，因此，本篇論文想探討是否細胞能透過改變5’LTR啟動子上DNA甲基化與組蛋白修飾等後基因修飾，而達到syncytin 2表現。實驗結果顯示，胎盤細胞或組織中的syncytin 2 5’LTR上甲基化程度顯著比非胎盤細胞來的低，且5’LTR上的組蛋白修飾皆為活化態的修飾，接著再利用報導基因方式發現syncytin 2 5’LTR若甲激化會影響到其轉錄活性，但有趣的是，含DNA甲基化syncytin 2 5’LTR的報導基因送胎盤細胞中，仍具有一定的轉錄活性，這表示胎盤細胞中具有特殊分子機制可對syncytin 2 5’LTR做去甲基化的動作；接著，發現胎盤組織特定轉錄因子GCMa可調控syncytin 2表現，且在非胎盤細胞MCF-7中表現GCMa後，會促進syncytin 2 5’LTR的DNA去甲基化，故GCMa轉錄因子除了調控基因表現外，同時在syncytin 2 5''LTR啟動子的去甲基化扮演重要角色；最後發現GCMa會與thymine DNA glycosylase（TDG）之間有結合能力，而TDG過去被指出可進行DNA去甲基化的酵素，因此GCMa可能透過吸引TDG至syncytin 2 5’LTR來進行DNA去甲基化的動作。綜合以上實驗結果，證實在胎盤細胞及非胎盤細胞中，syncytin 2 5’LTR上的後基因修飾有所不同，且胎盤特殊轉錄因子GCMa可促進syncytin 2 5’LTR DNA去甲基化以及啟動syncytin 2 mRNA表現。Syncytin 2, an envelope glycoprotein encoded by the human endogenous retrovirus FRD (HERV-FRD), is specifically expressed in placental trophoblasts. It has been reported that syncytin 2 is a fusogenic protein. Therefore, syncytin 2 may play an important role in placental development by regulation of trophoblastic fusion. Previous studies have shown that the placenta exhibits lower overall DNA methylation levels than the embryo. A recent study has shown that the 5’-long terminal repeat (5’LTR) promoter of syncytin 1, which encodes the envelope protein of HERV-W, is hypomehtylated and controls syncytin 1 expression in placenta. n this study, we further investigated whether DNA methylation and histone modification control syncytin 2 expression in placenta. We demonstrated that the 5’LTR of syncytin 2 is hypomethylated and harbors active histone modification in placental cells. In luciferase reporter assay, in vitro DNA methylation inhibited the promoter activity of syncytin 2 5’LTR. Interestingly, the promoter activity of in vitro methylated syncytin 2 5’LTR could be restored in placental cells. To study the mechanism that counteracts the suppressive effect of DNA methylation on syncytin 2 5’LTR promoter in placenta, we demonstrated that placental transcription factor, GCMa, not only regulates syncytin 2 expression but also promotes DNA demethylation on syncytin 2 5’LTR. We further demonstrated that GCMa associates with TDG, an enzyme that involves in DNA demethylation process. This implies that GCMa may recruit TDG to demethylate syncytin 2 5’LTR. Overall, our results reveal an epigenetic regulation of syncytin 2 gene expression and that GCMa is a key factor for DNA demethylation of syncytin 2 promoter and transcription activation of syncytin 2.目錄………………………………………………………………….…………………I文摘要…………………………………………………….………………..……...III文摘要…………………………………………………….……………………….IV一章 緒論. 胎盤.1 人類胎盤發育…………………………………………………………….1.2 胎盤功能………………………………………………………………….3. 後基因調控.1 簡介……………………………………………………………………….4.2去氧核糖酸甲基化………………………………………………….…….4.3 DNA methyltransferases………………………………………………..5.4 去氧核糖酸去甲基化……………………………………………………7.5 組蛋白修飾………………………………………………………………8. 人類內生性反轉錄病毒.1 簡介……………………………………………………………………….9.2 syncytin…………………………………………………………………10. gcm轉錄因子………………………………………………………………...12. 研究動機……………………………………………………………………14二章 材料與方法…………………………………………………………………15三章 結果. syncytin 2 5’LTR啟動子之DNA甲基化狀態...............................................25. syncytin 2 5’LTR啟動子上組蛋白修飾.........................................................26. 核酸甲基化對syncytin 2 5’LTR轉錄活性之影響………………………….26. GCMa調控syncytin2表現並促進syncytin 2 5’LTR區域的去甲基化…..28. GCMa在細胞中會與TDG作結合…………………………………………29四章 討論…………………………………………………………………………31五章 圖表…………………………………………………………………………35六章 參考文獻……………………………………………………………………4
Arachniodes amoena Ching 1962
No full textArachniodes amoena (Ching) Ching (1962: 256) ≡ Rumohra amoena Ching (1934: 40) (Fig. 4) Type:— CHINA. Guangdong: Yaoshan mountain, Ku Koong, 2 December 1931, Y.K. Wang 31553 (PE 00960338!). Voucher specimens examined:— VIETNAM. Quangtri Province: Huong Hoa District, Bac Huong Hoa Nature Reserve, Huong Phung Commune, Chenh Venh Village, along Sa Mù stream, 16°48’12.06”N, 106°35’55.52”E, elev. ca. 1200 m, 19 November 2014, Li Bing Zhang, Liang Zhang & Ngan T. Lu 7573 (CDBI!, MO, VNMN!). Distribution and habitat:— China (Fujian, Guangdong, Guangxi, Guizhou, Hunan, Jiangxi, Zhejiang), Vietnam (Quangtri). Arachniodes amoena is rare in Vietnam and only occurs in Quangtri, Central Vietnam. Notes:— Arachniodes amoena is most similar to A. tonkinensis Ching (Ching) (1962: 260) but A. amoena has a distinct terminal pinna whereas A. tonkinensis does not have a distinct terminal pinna. Additional specimens examined:— VIETNAM. Quangtri Province: Huong Hoa District, Bac Huong Hoa Nature Reserve, Huong Viet Commune, Ta Rung Villige, Sa Mu Pass, 16°48’44.08”N, 106°35’4.10”E, 21 November 2014, Li Bing Zhang, Liang Zhang & Ngan T. Lu 7612 (CDBI!, MO!, VNMN!). — CHINA. Guizhou: Mt. Leigong, Wudong, elev. ca. 1350 m, in forest, acidic soil, 19 September 2007, Li Bing Zhang et al. 0615 (CDBI!).Published as part of Lu, Ngan Thi, Wei, Hong-Jin, Vuong, Luong Dinh, Toan, Le Chi, Zhang, Li-Bing & Zhang, Liang, 2023, Cyrtomium calcis sp. nov. and six new records of the shield fern family (Dryopteridaceae) from Vietnam, pp. 15-26 in Phytotaxa 583 (1) on page 20, DOI: 10.11646/phytotaxa.583.1.2, http://zenodo.org/record/760903
The Wu-liang-shou-ching in Japan : A Guarantee of Women's Becoming Men
Get PDFHaving misread the Fa-hua-ching, the Japanese are convinced that women cannot become buddhas. With this conviction they are compelled to find a way to save hopeless women. Genku (1133-1212) tries to solve this problem on the authority of the Wu-liang-shou-ching: He says that, according to this sutra, Amida-butsu vowed in his previous existence to turn all women into men.4KJ00004274597論文Articledepartmental bulletin pape
The nomenclature of the lycophyte species Phlegmariurus mingcheensis Ching (Huperziaceae)
No full textIn 1982, Ren Chang Ching twice described the same lycophyte species under the names Lycopodium mingcheense (published in April; the original "minchegense" spelling being a correctable error) and Phlegmariurus mingcheensis Ching (published in May). Phlegmariurus mingcheensis cannot be taken as a combination based on Lycopodium mingcheense because in the original publication a different holotype was indicated and the name Lycopodium mingcheense was not mentioned. The correct names for this species in Huperzia, Lycopodium, and Phlegmariurus are Huperzia mingcheensis (Ching) Holub (basionym: Phlegmariurus mingcheensis), Lycopodium mingcheense Ching, and Phlegmariurus mingcheensis Ching, respectively. The recent lectotypification of the name Lycopodium mingcheense using P.S. Chiu 2069 (PE) was redundant since this specimen was clearly indicated as the holotype in Ching's original publication. The recent new name Phlegmariurus mingjoui X.C. Zhang is an illegitimate superfluous name
GCM1 Regulation of the Expression of Syncytin 2 and Its Cognate Receptor MFSD2A in human Placenta.
No full text[[sponsorship]]生物化學研究所[[note]]已出版;[SCI];有審查制度;具代表性[[note]]http://gateway.isiknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=Drexel&SrcApp=hagerty_opac&KeyRecord=0006-3363&DestApp=JCR&RQ=IF_CAT_BOXPLOT[[note]]http://gateway.isiknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=RID&SrcApp=RID&DestLinkType=FullRecord&DestApp=ALL_WOS&KeyUT=00028115380001
Mapping the Discipline of the Olympic Games An Author-Cocitation Analysis
Get PDFThe authors conducted an author cocitation analysis on prominent authors writing about the Olympics during the 1990s. Author cocitation is an established bibliometric technique that can be used to measure the relative similarities of topics written about by the cited authors. This enables a visual representation of the “intellectual space” of the discipline, in this case the Olympics, to be created for the period under review. So core and peripheral research areas are identified, along with their major contributors. The representation appears as a two-dimensional cluster-enhanced map. Subject expertise was then applied to the results to place labels on the generated clusters of authors and their topics
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