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.

A few experiments have compared frameshifting rates under different growth phases. Some bacterial frameshifting is known directly or by inference, to greatly increase when cells enter stationary phase ( Figure 19 . Programmed transcriptional frameshifting in members of the Paramyxovirinae. In the P-gene mRNA of Sendai virus, the insertion of a G occurs over the minus strand template RNA slippery sequence UUUUUUCCC. In 30% of the population (middle panel), a pause in RdRp over the slippery sequence promotes slippage of a G-C bond to form G:U pairs (in red dotted lines). Polymerization resumes by addition of a G (in green) over the critical C (in pink), thus encoding mRNA for the V-protein in an overlapping translational −1 frame compared to genomic template. The panel to the right shows that the potential insertion of two G's has very poor likelihood due to multiple G-U pairs not being tolerated. Inset: Hexamer phasing in members of the Paramyxovirinae. The ribonucleoprotein (RNP) structure is a left-handed coil where each nucleocapsid protein binds precisely 6 nucleotides. a tRNA relevant to a Streptomyces phage candidate bypassing (161) , is mainly restricted to the stationary phase that is irrelevant to phage infection (162) . Dependence of some plant (e.g. luteovirus), and animal (cardioviruses and HIV), viral frameshifting on viral life cycle stage or cell status is described above. Frameshifting to synthesize S. cerevisiae Ty1 and/or its close relative Ty2, GagPol changes in a growth-stage dependent manner (624, 625) . Cell cycle stage relevance of EST3 and antizyme frameshifting is also described above.