What name is given to the process in which pre-mRNA is edited into mRNA?

RNases and proteases are enzymes that destroy RNAs and proteins, respectively. Which of the following enzymes, if added to a spliceosome, would be predicted to prevent recognition of pre-mRNA regions critical for splicing?

a. An RNase specific for tRNAs

b. An RNase specific for snRNAs

c. A protease specific for initiation factors

d. A protease specific for a release factor

Would the coupling of the processes shown in Figure 17.24 be found in a eukaryotic cell? Explain why or why not.

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Eating even a single death cap mushroom (Amanita phalloides) can be fatal due to a compound called α-amanitin, a toxin that inhibits transcription.

Biologists have investigated how fast pre-mRNA splicing occurs by treating cells with a toxin that blocks the production of new pre-mRNAs, then following the rate of splicing of the pre-mRNAs that were transcribed before adding the toxin. Why is addition of a toxin important in this study?