Substitution of one nucleotide for another in the middle of the coding sequence.
6–11 Prokaryotes and eukaryotes both protect against the dangers of translating broken mRNAs. What dangers do partial mRNAs pose for the cell?
6–12 Both hsp60-like and hsp70 molecular chaperones share an affinity for exposed hydrophobic patches on proteins, using them as indicators of incomplete folding. Why do you suppose hydrophobic patches serve as critical signals for the folding status of a protein?
6–13 Most proteins require molecular chaperones to assist in their correct folding. How do you suppose the chaperones themselves manage to fold correctly?
6–14 What is so special about RNA that it is hypothesized to be an evolutionary precursor to DNA and protein? What is it about DNA that makes it a better material than RNA for storage of genetic information?
6–15 If an RNA molecule could form a hairpin with a symmetric internal loop, as shown in Figure Q6–5, could the complement of this RNA form a similar structure? If so, would there be any regions of the two structures that are identical? Which ones?
Figure Q6–5 An RNA hairpin with 5’-G-C-A C-C-G a symmetric internal loop (Problem U 6–15).
6–16 Imagine a warm pond on the primordial Earth. Chance processes have just assembled a single copy of an RNA molecule with a catalytic site that can carry out RNA replication. This RNA molecule folds into a structure that is capable of linking nucleotides according to instructions in an RNA template. Given an adequate supply of nucleotides, will this single RNA molecule be able to use itself as a template to catalyze its own replication? Why or why not?
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From DNA to RNA
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