The stimulation of Rho-dependent termination by high Mg2 + is specific to the mgtA leader because high Mg2 .
If the nucleotides in the R2 regions of the mgtA leader are essential for stimulation of Rho activity , mutations in R2 should overcome the silencing effect of the C145G substitution .
If the nucleotides in the R2 regions of the mgtA leader are essential for stimulation of Rho activity , mutations in R1 should overcome the silencing effect of the C145G substitution .
If the nucleotides in the R1 regions of the mgtA leader are essential for stimulation of Rho activity , mutations in R2 should overcome the silencing effect of the C145G substitution .
If the nucleotides in the R1 regions of the mgtA leader are essential for stimulation of Rho activity , mutations in R1 should overcome the silencing effect of the C145G substitution .