How does the shape of the RNA affect what it will cause the ribosomes in a cell to make?
There are many known examples of RNA messages that turn on or turn off ribosome translation based on the exposure or protection of special ribosome-binding sequences internal to the messages. Some RNAs, via their folding, also somehow cause frameshifting of translation, early termination of translation, or early decay (promoting the degradation of the RNA by nucleases in the cell). RNAs also are spliced (copied/pasted) into numerous variants in different human cells, and this process appears to depend on the RNA’s fold and its ability to bind other RNAs which form the core components of the spliceosome.
So there are lots of ways an RNA’s fold determines what the ribosomes will make – not surprising perhaps, given that the ribosome (and the gene-decoding tRNAs) themselves are primarily RNA and thus well-poised to bind and co-fold with the message
That being said – the complete ‘RNA code’ has not been cracked. We can’t take an RNA’s sequence and *predict* how it will splice, get translated, how long it wil live, or what will turn on or off its expression, decay, or translation.
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