Browsing by Author "Cui, Xiaopei"

Now showing 1 - 3 of 3

Hypoxia-responsive miRNAs target argonaute 1 to promote angiogenesis
(2013-03-01)
Chen, Zhen
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Lai, Tsung-Ching
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Jan, Yi-Hua
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Lin, Feng-Mao
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Wang, Wei-Chi
Despite a general repression of translation under hypoxia, cells selectively upregulate a set of hypoxia-inducible genes. Results from deep sequencing revealed that Let-7 and miR-103/107 are hypoxia-responsive microRNAs (HRMs) that are strongly induced in vascular endothelial cells. In silico bioinformatics and in vitro validation showed that these HRMs are induced by HIF1 alpha and target argonaute 1 (AGO1), which anchors the microRNA-induced silencing complex (miRISC). HRM targeting of AGO1 resulted in the translational desuppression of VEGF mRNA. Inhibition of HRM or overexpression of AGO1 without the 3' untranslated region decreased hypoxia-induced angiogenesis. Conversely, AGO1 knockdown increased angiogenesis under normoxia in vivo. In addition, data from tumor xenografts and human cancer specimens indicate that AGO1-mediated translational desuppression of VEGF may be associated with tumor angiogenesis and poor prognosis. These fmdings provide evidence for an angiogenic pathway involving HRMs that target AGO1 and suggest that this pathway may be a suitable target for anti- or proangiogenesis strategies.
MicroRNA-483 amelioration of experimental pulmonary hypertension
(2020-05-08)
Zhang, Jin
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He, Yangyang
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Yan, Xiaosong
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Chen, Shanshan
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He, Ming
Endothelial dysfunction is critically involved in the pathogenesis of pulmonary arterial hypertension (PAH) and that exogenously administered microRNA may be of therapeutic benefit. Lower levels of miR-483 were found in serum from patients with idiopathic pulmonary arterial hypertension (IPAH), particularly those with more severe disease. RNA-seq and bioinformatics analyses showed that miR-483 targets several PAH-related genes, including transforming growth factor-beta (TGF-beta), TGF-beta receptor 2 (TGFBR2), beta-catenin, connective tissue growth factor (CTGF), interleukin-1 beta (IL-1 beta), and endothelin-1 (ET-1). Overexpression of miR-483 in ECs inhibited inflammatory and fibrogenic responses, revealed by the decreased expression of TGF-beta, TGFBR2, beta-catenin, CTGF, IL-1 beta, and ET-1. In contrast, inhibition of miR-483 increased these genes in ECs. Rats with EC-specific miR-483 overexpression exhibited ameliorated pulmonary hypertension (PH) and reduced right ventricular hypertrophy on challenge with monocrotaline (MCT) or Sugen + hypoxia. A reversal effect was observed in rats that received MCT with inhaled lentivirus overexpressing miR-483. These results indicate that PAH is associated with a reduced level of miR-483 and that miR-483 might reduce experimental PH by inhibition of multiple adverse responses.
The C-Terminus of a Subunit Determines The Catalytic Activity of AMP-activated Protein Kinase
(2010-04-01)
Cui, Xiaopei
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Gao, Haiqing
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Hwang, Jenn-Kang
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Shyy, John Y-J
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生物資訊及系統生物研究所