Plants: miRNA and RNA silencing

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Plants miRNA and RNA silencing
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pre-miRNA structure
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miRNAbiogenesis
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small RNA biogenesis
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miRNA in plantsdevelopmental role
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miRNA siRNA in action
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RdDM RNA-directed DNA Methylation
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miRNA research tools

• biochemical approach
• isolation, RT, PCR, concatamerization, sequencing
• microarrays (tissue specificity)
• bioinformatic alignment studies
• grafting experiments
• A. tumefaciens infiltration assay
• wheat germ in vitro assay
• in vivo cleavage product detection

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miRNA research tools

• biochemical approach
• bioinformatic alignment studies
• high complementarity to target mRNAs in plants
• needs experimental confirmation
• grafting experiments
• A. tumefaciens infiltration assay
• wheat germ in vitro assay
• in vivo cleavage product detection

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miRNA research tools

• biochemical approach
• bioinformatic alignment studies
• grafting experiments
• intercellular RNA signaling through PD phloem
• A. tumefaciens infiltration assay
• wheat germ in vitro assay
• in vivo cleavage product detection

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miRNA research tools

• biochemical approach
• bioinformatic alignment studies
• grafting experiments
• A. tumefaciens infiltration assay
• binary shRNA vectors available
• constitutive knockdown of target genes
• wheat germ in vitro assay
• in vivo cleavage product detection

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miRNA research tools

• biochemical approach
• bioinformatic alignment studies
• grafting experiments
• A. tumefaciens infiltration assay
• wheat germ in vitro assay
• contains DCL, RdRP
• in vivo cleavage product detection

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miRNA research tools

• biochemical approach
• bioinformatic alignment studies
• grafting experiments
• A. tumefaciens infiltration assay
• wheat germ in vitro assay
• in vivo cleavage product detection
• sensor technology

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Role and conservation of Arabidopsis miRNA
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miRNAs important for plant development
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effects of miRNA156 overexpression
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miRNAs important for plant development
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effects of miRNA164b overexpression
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miRNA siRNA application
Genscript RNAi vector
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miRNA siRNA application

• research
• gene knockdown
• transient by siRNA infiltration
• constitutive by shRNA binary vectors
• tissue-specific by adequate promoters
• chromatin-based transcriptional silencing
• promoter silencing
• transposon silencing
• agriculture
• adapt plant mechanism to combat viral infections
• silencing in related species (eg. male sterility
  in crops)
• BASF plant nonhost disease resistance screen
• medicine
• gene therapy siRNA drugs