9,230 research outputs found
vegetable seedling feature extraction using stereo color imaging
No full textvegetable seedling feature extraction using stereo color imaging. ta-te lin. jeng-ming chang. department of agricultural machinery engineering.. national taiwan university.. taipei. taiwan. roc. introductio
Study of microRNAs involved in wounding response n sweet potato
No full textmicroRNA (miRNA)是一段由生物體內自行合成約21-24鹼基的小分子核醣核酸，不轉譯出任何蛋白，其藉由降解mRNA或抑制mRNA進行蛋白質轉譯來達成調控基因表現。近年來在阿拉伯芥上發現超過百種的miRNA，且研究指出miRNA參與植物不同階段的生長發育及抵抗不同環境的變化，所以我們對於與植物傷害相關的miRNA有著極大興趣，希望探討傷害相關miRNA的訊息傳遞的過程。藉由miRNA序列在演化具有高度保留性的特性，利用阿拉伯芥miRNA的序列當作探針探討甘藷植株在遭受傷害後miR159、miR407、miR828的表現情形。在甘藷植株中無偵測到miR407的表現；miR159可在莖中被偵測到，而在葉中表現量極低；miR828則在葉中被偵測到。此外，在甘藷傷害後，miR159表現量並未隨時間不同有所變化，而miR828表現量卻會被抑制。且處理誘導傷害防禦機制相關的分子，如:過氧化氫(hydrogen peroxide, H2O2)、一氧化氮(nitric oxide, NO)、甲基茉莉酸(Methyl jasmonate, MeJA)、離層酸(abscisic acid, ABA)及乙烯(ethylene)，也會抑制miR828的表現。我們再藉由不同誘導劑與抑制劑探討miR828表現情形進而探討其訊息傳遞的過程，推測植物傷害後，促使NO與MeJA生合成，而MeJA也會而活化NOS產生NO，而NO再活化NADPH oxidase產生H2O2，或者MeJA本身也會透過過其他分子，而抑制miR828表現進而調控miR828標的基因表現。此外，ethylene也會透過MeJA抑制miR828表現，而一氧化碳(carbon monoxide, CO)會在之中清除H2O2進而抑制傳遞過程。而miRNA藉由序列互補性辨識標的基因，進而對標的基因進行靜默 (silencing)。我們利用cDNA clone釣取到三個可能的miR828標的基因，分別為receptor protein kinase (RPK)、TLD和MYB。藉由傷害後因miR828表現被抑制而減少對標的基因mRNA降解或降低抑制標的基因蛋白質轉譯，使得標的基因的表現進而參與傷害防禦調控機制。MicroRNAs (miRNAs) contain approximate 22 nucleotides that post-transcriptionally regulate gene expression by directing mRNA cleavage or translational inhibition. Currently, more than one hundred miRNAs that play multiple roles in growth, development, and stress responses of plants have been identified in Arabidopsis thaliana. Here, I investigated the expression patterns of miR159, miR407, and miRNA828 upon wounding in sweet potato. The expression of miR407 was undetectable in leaves and stems. However, miR159 was expressed in stems and, at low levels, in leaves, whereas miR828 was expressed in leaves and undetectable in stems. Furthermore, the expression of miR828 was decreased upon wounding in sweet potato. Additionally, several defensive responding compounds, including hydrogen peroxide (H2O2), nitric oxide (NO), methyl jasmonate (MeJA), abscisic acid (ABA), and ethylene also suppressed miR828 expression. However, carbon monoxide (CO) suppressed repression of miR828 by wounding. Interactions among these defensive responding compounds for the regulation of miR828 were also studied. Results suggested that wounding stimulates the biosynthesis of MeJA and NO. Then, MeJA activates NO synthase to generate NO. Finally, NO inspires the activity of NADPH oxidase to generate H2O2, which suppress miR828 expression. In addition to miR828, three potential miR828 targeted genes, receptor protein kinase (RPK), TLD, and MYB were isolated and were up-regulated by wounding. In addition, RPK, TLD, and MYB were regulated by NO and H2O2 when miR828 was repressed. These results imply that wounding represses the expression of miR828, and consequently regulates the expression of RPK, TLD, and MYB genes to protect plants from damage.中文摘要 文摘要 一章 前言 一、植物的防禦機制•••••••••••••••••••••••••••••••••••••• 1二、miRNA的作用與機制•••••••••••••••••••••••••••••••••• 3三、實驗方向與目的•••••••••••••••••••••••••••••••••••••• 7二章 材料與方法 一、材料••••••••••••••••••••••••••••••••••••••••••••• 8二、實驗材料處理與藥劑••••••••••••••••••••••••••••••••••• 8三、Total RNA萃取•••••••••••••••••••••••••••••••••••••• 9四、Small RNA電泳•••••••••••••••••••••••••••••••••••••• 9五、北方墨點法分析•••••••••••••••••••••••••••••••••••••• 9六、Rapid Amplification of cDNA Ends (RACE)••••••••••••••••••••• 11七、質體構築•••••••••••••••••••••••••••••••••••••••••• 13八、Reverse transcription-polymerase chain reaction (RT-PCR)••• ••••••••• 14九、Small RNA釣取•••••••••••••••••••••••••••••••••••••• 15三章 結果 一、miRNA在甘藷傷害表現之確認•••••••••••••••••••••••••••• 18二、miR828訊息傳導••••••••••••••••••••••••••••••••••••• 19三、miR828標的基因••••••••••••••••••••••••••••••••••••• 23四、甘藷miRNA釣取••••••••••••••••••••••••••••••••••••• 26四章 討論 一、 miR159、miR407、miR828表現情形••••••••••••••••••••••••• 27二、miR828的訊息傳遞過程•••••••••••••••••••••••••••••••• 28三、miR828標的基因表現情形••••••••••••••••••••••••••••••• 32四、結論••••••••••••••••••••••••••••••••••••••••••••• 35表••••••••••••••••••••••••••••••••••••••••••••••••••••••• 36考文獻•••••••••••••••••••••••••••••••••••••••••••••••••••• 5
Nitric oxide activates superoxide dismutase and ascorbate peroxidase to repress the cell death induced by wounding
No full textThe stem cell E3-ligase Lin-41 promotes liver cancer progression through inhibition of microRNA-mediated gene silencing
No full textLin-41 is a stem cell-specific E3 ligase and a known target of the tumour suppressor microRNA (miRNA) let-7. Lin-41 was recently reported to mediate ubiquitylation and degradation of the miRNA pathway protein Ago2. We demonstrate that Lin-41 is over-expressed in hepatocellular carcinoma (HCC). Lin-41 over-expression correlates with high a-fetoprotein level, high tumour grade and high tumour stage and predicts early tumour recurrence. Lin-41 is a strong predictor of poor long-term survival for patients with HCC. Lin-41 knock-down by RNA interference in HCC cell lines Huh7 and Hep3B suppressed proliferation in vitro and reduced in vivo tumour growth in NOD/SCID mice. On the other hand, over-expression of Lin-41 in the HCC cell line SK-Hep1 enhanced tumourigenicity. Over-expression and knock-down of Lin-41 led to inverse changes in the levels of Ago1 and Ago2 proteins. Over-expression of Ago1 and Ago2 reduced in vivo tumour growth. Lin-41 over-expression suppressed let-7 activity in HCC cell lines and expression of Lin-41 enhanced the expression of let-7-regulated oncogenes c-Myc, Lin-28B, HMGA2 and type 1 insulin-like growth factor receptor (IGF1R). Expression of Lin-28B and c-Myc enhanced the expression of Lin-41. Chromatin immunoprecipitation and reporter assays revealed direct association of c-Myc with the Lin-41 promoter, resulting in transcriptional transactivation. Our results indicate that Lin-41 plays an important role in the growth of HCC by regulating RISC complex proteins Ago1 and Ago2 to inhibit miRNA-mediated gene silencing and promote the expression of oncogenic proteins. Lin-41 is also a strong prognostic factor for patients with HCC. Copyright (C) 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd
Shane and Hannah Burcaw
No full textShane Burcaw is the author of the bestselling memoir, Laughing at My Nightmare, which was shortlisted for the ALA Excellence in Nonfiction Award. He has also published the essay collection Strangers Assume that My Girlfriend Is My Nurse and is at work with his wife Hannah on a collection of stories about interabled couples. His blog, Laughing At My Nightmare, about the humor of living with Spinal Muscular Atrophy, has over half a million followers and he and his wife’s You Tube channel, Squirmy and Grubs, has nearly 1 million subscribers
Munidopsis sarissa Lin, Osawa & Chan 2007
No full textMunidopsis sarissa Lin, Osawa & Chan, 2007 Munidopsis sarissa Lin et al., 2007: 167, figs 1–3 (Taiwan, 960–1010 m). Type data: holotype, male, NTOU A008820. Type locality: Taiwan, 22º17.16´N, 119º59.91´E, 960–972 m.Published as part of Baba, Keiji, Macpherson, Enrique, Poore, Gary C. B., Ahyong, Shane T., Bermudez, Adriana, Cabezas, Patricia, Lin, Chia-Wei, Nizinski, Martha, Rodrigues, Celso & Schnabel, Kareen E., 2008, Catalogue of squat lobsters of the world (Crustacea: Decapoda: Anomura-families Chirostylidae, Galatheidae and Kiwaidae), pp. 1-220 in Zootaxa 1905 (1) on page 158, DOI: 10.11646/zootaxa.1905.1.1, http://zenodo.org/record/513458
Munidopsis dentifalx Osawa, Lin & Chan 2007
No full textMunidopsis dentifalx Osawa, Lin & Chan, 2007 Munidopsis dentifalx Osawa, Lin & Chan, 2007: 15, figs 1–3 (between Negros and Mindanao, Philippines, 2120–2323 m). Type data: holotype, ovigerous female, NMCR. Type locality: Philippines, 8°49.6´N, 123°02.6´E, 2120–2149 m.Published as part of Baba, Keiji, Macpherson, Enrique, Poore, Gary C. B., Ahyong, Shane T., Bermudez, Adriana, Cabezas, Patricia, Lin, Chia-Wei, Nizinski, Martha, Rodrigues, Celso & Schnabel, Kareen E., 2008, Catalogue of squat lobsters of the world (Crustacea: Decapoda: Anomura-families Chirostylidae, Galatheidae and Kiwaidae), pp. 1-220 in Zootaxa 1905 (1) on page 140, DOI: 10.11646/zootaxa.1905.1.1, http://zenodo.org/record/513458
sj-docx-1-psw-10.1177_14789299221134935 – Supplemental material for Does Politicians’ Negative Social Media Communication Backfire? A Case Study of Former US President Trump
No full textSupplemental material, sj-docx-1-psw-10.1177_14789299221134935 for Does Politicians’ Negative Social Media Communication Backfire? A Case Study of Former US President Trump by Hsuan-Yu (Shane) Lin in Political Studies Review</p
Munidopsis latiangulata Osawa, Lin & Chan 2006
No full textMunidopsis latiangulata Osawa, Lin & Chan, 2006 Munidopsis latiangulata Osawa et al., 2006b: 251, figs 1–4 (Taiwan, 2220–2424 m). Type data: holotype, ovigerous female, NTOU A00804. Type locality: Taiwan, 24º16.34´N, 122º11.67´E, 2220–2424 m.Published as part of Baba, Keiji, Macpherson, Enrique, Poore, Gary C. B., Ahyong, Shane T., Bermudez, Adriana, Cabezas, Patricia, Lin, Chia-Wei, Nizinski, Martha, Rodrigues, Celso & Schnabel, Kareen E., 2008, Catalogue of squat lobsters of the world (Crustacea: Decapoda: Anomura-families Chirostylidae, Galatheidae and Kiwaidae), pp. 1-220 in Zootaxa 1905 (1) on page 146, DOI: 10.11646/zootaxa.1905.1.1, http://zenodo.org/record/513458
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