Why doesn't polynucleotide phosphorylase (Ochoa's enzyme) synthesize RNA in vivo?
Present an overview of RNA interference (RNAi). How does the silencing process begin, and what major components participate?
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Verified Solution
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Key Concepts
RNA Interference (RNAi)
Dicer and siRNA
RNA-Induced Silencing Complex (RISC)
Refer to Table 13.1. Can you hypothesize why a synthetic RNA composed of a mixture of poly U poly A would not stimulate incorporation of ¹⁴C-phenylalanine into protein?
In 1998, future Nobel laureates Andrew Fire and Craig Mello, and colleagues, published an article in Nature entitled, 'Potent and Specific Genetic Interference by Double-Stranded RNA in Caenorhabditis elegans.' Explain how RNAi is both 'potent and specific.'
A short RNA molecule was isolated that demonstrated a hyperchromic shift (see Chapter 10), indicating secondary structure. Its sequence was determined to be
5'-AGGCGCCGACUCUACU-3'
Propose a two-dimensional model for this molecule.
A short RNA molecule was isolated that demonstrated a hyperchromic shift (see Chapter 10), indicating secondary structure. Its sequence was determined to be
5'-AGGCGCCGACUCUACU-3'
What DNA sequence would give rise to this RNA molecule through transcription?
RNAi may be directed by small interfering RNAs (siRNAs) or microRNAs (miRNAs); how are these similar, and how are they different?