Ribosomal frameshifting and transcriptional slippage: From genetic steganography and cryptography to adventitious use

Atkins, John F.; Loughran, Gary; Bhatt, Pramod R.; Firth, Andrew E.; Baranov, Pavel V.

AUG. Doubtless applicability of the word 'steganography' to certain forms of genetic recoding and frameshifting in particular, was not envisaged when it was first used in 1499 to mean an intended secret message that does not attract attention in contrast to cryptography where just the contents of the hidden message is protected and not its existence. Nevertheless, its use in connection with productively utilized frameshifting by Patrick Moore (1) highlights the extra N-terminally coincident product(s) whose synthesis involves a switch from the frame set at initiation to one of the two alternative reading frames (registers) inherent with standard non-overlapping triplet decoding (Figure 1 ). The frameshift-derived product is generally quite different in both length and sequence from the product of standard decoding. It is not only ribosomal frameshifting that can yield a trans-frame encoded protein, but also where the RNA polymerase 'slips' to yield mRNA lacking or containing one or more extra bases (that are not 3 nt or multiples thereof). Such 'transcriptional frameshifting' also yields products that are trans-frame specified with respect to sequence present in the encoding DNA (or RNA in the case of some viruses).